Corpus

Abstract The demand for flexible and printed electronics in wearable and soft robotics applications has increased the need for scalable, additive manufacturing processes. However, traditional printed circuit board manufacturing involves complex, multistep processes, is limited to certain substrates, and faces challenges in integrating functional devices. Here, an additive, laser‐enabled process is introduced for fabricating flexible, double‐sided printed electronics leveraging laser‐induced graphene (LIG) as a seed layer for selective copper electrodeposition (E‐LIG). This technique enables precise conductive circuit patterning down to 50 µm and is reliable via formation in a single streamlined process. E‐LIG supports transfer to various substrates, allowing for large‐area electronics up to 100 cm 2 , broadening applications in large‐scale interfaces. Functional LIG device integration, including sensors and actuators, directly interfaced with control circuits on a single substrate is demonstrated. Applications such as real‐time graphical output and interactive interfacing showcase the method's versatility. E‐LIG exhibits repairability for on‐demand restoration of damaged circuits, enhancing durability and offering a scalable, cost‐effective solution for multifunctional printed electronics.

Flexible Printed Electronics In article number 2415272, Wedyan Babatain and co-workers introduce a laser-enabled, additive process for fabricating flexible, double-sided PCBs. The E-LIG process combines laser-induced graphene patterning with copper electrodeposition, creating high-resolution circuits that integrate sensors and actuators directly on flexible or transparent substrates. This scalable method is ideal for wearables, soft robotics, and interactive smart surfaces.

Maritime transport significantly contributes to global emissions, prompting the International Maritime Organization to implement stricter regulations to reduce pollution. Since 2020, fuel sulfur (S) content limits have been reduced, requiring either the use of low-S fuels or the installation of marine scrubbers to continue using heavy fuel oil (HFO). While scrubbers are a widely adopted solution for reducing S emissions, their benefits are controversial and uncertainty remains regarding scrubber environmental impacts and their appropriate evaluation. Here, we systematically assess the environmental impacts of scrubbers operating on HFO to those of low-S fuels across various categories, through a measurement-informed Well-to-Wake (WtW) life cycle assessment (LCA). Gaseous and particulate matter (PM) emissions data were collected while a bulk carrier vessel was burning 3% S HFO, 0.1% S marine gas oil (MGO), and 0.5% S very low-S fuel oil (VLSFO) under similar engine operating modes during an actual ocean voyage. Seawater and washwater samples were also analyzed, alongside fuel, cylinder oil, and lubricant samples. The results suggest that, in various instances the use of HFO with a scrubber can be considered equivalent to MGO use while outperforming VLSFO use from a WtW perspective, for large, ocean-going bulk carrier vessels in open seas. These findings indicate that end-of-pipe solutions may not always be inferior to start-of-pipe alternatives, underscoring the need for comprehensive LCA studies to properly assess emission abatement technologies.

The Adiabatic Quantum Flux Parametron (AQFP) superconducting logic family is an attractive beyond-CMOS technology due to its extreme energy efficiency. As AQFP circuits become more complex and target applications scale to microprocessors and ASICs, a high performance and area efficient register-level memory design is essential. In this work, we design and implement a 3-bit memory cell based on a simple Set-Reset (SR) latch attached to a shift register feedback loop. This design is more compact than existing AQFP registers that encode data with Data-Enable logic and therefore require larger XOR-style gates for every 1-bit cell (Tsuji et al., 2017). Furthermore, we share layout design and simulation results for scaling this circuit to an 8-bit memory cell and a N-row × M-col × 8-bit register file. By using SR data encoding, we are able to join the cells in an array using more compact AND gates, performing cell-level addressing with two write demuxes and two read decoders. Projecting our initial designs to a 32-word by 8-bit register file, we find that our SR-loop memory array has a 26% decrease in area compared to other state-of-the-art designs.

Prototyping large, electronically integrated structures is challenging and often results in unwieldy wiring, weak mechanical properties, expensive iterations, or limited reusability. While many electronics prototyping kits exist for small-scale objects, relatively few methods exist to freely iterate large and sturdy structures with integrated electronics. To address this gap, we present the Voxel Invention Kit (VIK), which uses reconfigurable blocks that assemble into high-stiffness, lightweight structures with integrated electronics. We do this by creating cubic blocks composed of PCBs that carry electrical routing and components and can be (re)configured with simple tools into a variety of structures. To ensure structural stability without expertise, we created a tool to configure structures and simulate applied loads, which we validated with mechanical testing data. Using VIK, we produced devices reconfigured from a shared set of voxels: multiple iterations of a customizable AV lounge seat, a dance floor game, and a force-sensing bridge.

Recent developments in Generative AI enable creators to stylize 3D models based on text prompts. These methods change the 3D model geometry, which can compromise the model’s structural integrity once fabricated. We present MechStyle, a system that enables creators to stylize 3D printable models while preserving their structural integrity. MechStyle accomplishes this by augmenting the Generative AI-based stylization process with feedback from a Finite Element Analysis (FEA) simulation. As the stylization process modifies the geometry to approximate the desired style, feedback from the FEA simulation reduces modifications to regions with increased stress. We evaluate the effectiveness of FEA simulation feedback in the augmented stylization process by comparing three stylization control strategies. We also investigate the time efficiency of our approach by comparing three adaptive scheduling strategies. Finally, we demonstrate MechStyle’s user interface that allows users to generate stylized and structurally viable 3D models and provide five example applications.

Although digital fabrication processes at the desktop scale have become proficient and prolific, systems aimed at producing larger-scale structures are still typically complex, expensive, and unreliable. In this work, we present an approach for the fabrication of scalable macroscale structures using simple robots and interlocking lattice building blocks. A target structure is first voxelized so that it can be populated with an architected lattice. These voxels are then grouped into larger interconnected blocks, which are produced using standard digital fabrication processes, leveraging their capability to produce highly complex geometries at a small scale. These blocks, on the size scale of tens of centimeters, are then fed to mobile relative robots that are able to traverse over the structure and place new blocks to form structures on the meter scale. To facilitate the assembly of large structures, we introduce a live digital twin simulation tool for controlling and coordinating assembly robots that enables both global planning for a target structure and live user design, interaction, or intervention. To improve assembly throughput, we introduce a new modular assembly robot, designed for hierarchical voxel handling. We validate this system by demonstrating the voxelization, hierarchical blocking, path planning, and robotic fabrication of a set of meter-scale objects.

We present a system that transforms speech into physical objects using 3D generative AI and discrete robotic assembly. By leveraging natural language, the system makes design and manufacturing more accessible to people without expertise in 3D modeling or robotic programming. While generative AI models can produce a wide range of 3D meshes, AI-generated meshes are not directly suitable for robotic assembly or account for fabrication constraints. To address this, we contribute a workflow that integrates natural language, 3D generative AI, geometric processing, and discrete robotic assembly. The system discretizes the AI-generated geometry and modifies it to meet fabrication constraints such as component count, overhangs, and connectivity to ensure feasible physical assembly. The results are demonstrated through the assembly of various objects, ranging from chairs to shelves, which are prompted via speech and realized within 5 minutes using a robotic arm.

Recent developments in Generative AI enable creators to stylize 3D models based on text and image prompts. These methods change the 3D model geometry, which can compromise the model’s structural integrity once fabricated. We present MechStyle, a system that enables creators to stylize 3D printable models while preserving their structural integrity. MechStyle accomplishes this by augmenting the Generative AI-based stylization process with feedback from a Finite Element Analysis (FEA) simulation. As the stylization process modifies the geometry to approximate the desired style, feedback from the FEA simulation reduces modifications to regions with increased stress. In this demonstration, attendees can interact with MechStyle’s prompt-based UI, observe simulation-informed stylization results, and explore a curated collection of 3D printed objects generated using MechStyle. These artifacts showcase the system’s ability to produce physically plausible, stylized designs across a range of prompts and model types. This hands-on experience highlights MechStyle’s potential to bridge high-level design intent with low-level fabrication constraints in generative workflows.

Advanced materials hold great promise, but their adoption is impeded by the challenges of developing, characterizing, and modeling them, then of designing, processing, and producing something with them. Even if the results are open, the means to do each of these steps are typically proprietary and segregated. We show how principles of open-source software and hardware can be used to develop open instrumentation for materials science, so that a measurement can be accompanied by a complete computational description of how to reproduce it. And then we show how this approach can be extended to effectively measure predictive computational models rather than just model parameters. We refer to these interrelated concepts as "computational metrology." These are illustrated with examples including a 3D printer that can do rheological characterization of unfamiliar and variable materials. Graphical abstract: A demonstration of computational metrology is shown through the development of a Rheoprinter (left) that combines off-the-shelf printer components with custom instrumentation. At right, a model made by the Rheoprinter to predict relative nozzle pressures as a function of material flow rate and nozzle temperature.

3D generative AI enables rapid and accessible creation of 3D models from text or image inputs. However, translating these outputs into physical objects remains a challenge due to the constraints in the physical world. Recent studies have focused on improving the capabilities of 3D generative AI to produce fabricable outputs, with 3D printing as the main fabrication method. However, this workshop paper calls for a broader perspective by considering how fabrication methods align with the capabilities of 3D generative AI. As a case study, we present a novel system using discrete robotic assembly and 3D generative AI to make physical objects. Through this work, we identified five key aspects to consider in a physical making process based on the capabilities of 3D generative AI. 1) Fabrication Constraints: Current text-to-3D models can generate a wide range of 3D designs, requiring fabrication methods that can adapt to the variability of generative AI outputs. 2) Time: While generative AI can generate 3D models in seconds, fabricating physical objects can take hours or even days. Faster production could enable a closer iterative design loop between humans and AI in the making process. 3) Sustainability: Although text-to-3D models can generate thousands of models in the digital world, extending this capability to the real world would be resource-intensive, unsustainable and irresponsible. 4) Functionality: Unlike digital outputs from 3D generative AI models, the fabrication method plays a crucial role in the usability of physical objects. 5) Accessibility: While generative AI simplifies 3D model creation, the need for fabrication equipment can limit participation, making AI-assisted creation less inclusive. These five key aspects provide a framework for assessing how well a physical making process aligns with the capabilities of 3D generative AI and values in the world.

Abstract We document experimentally at model scale net viscous drag reduction of at least 7.5% in streamlined hulls with high block coefficient, potentially applicable to bulk carriers and tankers, using wedge shaped vortex generators (VGs). We also establish scaling laws proving that at full-scale drag reduction is fully preserved, and estimate the size and cost of VG installation and the gains that can be materialized in ship operations. INTRODUCTION The International Maritime Organization (IMO) has set strict carbon emission reduction goals for the shipping industry. By 2050, IMO requires net zero greenhouse gas emissions and has goals for at least a 20% reduction by 2030, and 70% by 2040. To reach these ambitious goals, short, medium, and long-term solutions must be utilized. Ultimately, a transition in prime movers and fuel type will be required to reach 100% greenhouse gas emission reduction, but in the short and medium term, means for reducing drag and improving hull efficiency will enable achieving the 2030 and 2040 goals, and will make the 2050 goal more easily attainable. With this goal in mind, we investigated the use of Vortex Generators (VGs) to reduce the viscous resistance of high block coefficient ships. For example, fuller shaped ships such as bulk carriers and tankers that have block coefficients up to 0.85 (the block coefficient is the ratio of the volume of the ship divided by the volume of the "box" that contains it, viz. the product of the length, beam, and draft), although streamlined with high length to-beam ratios, can have pressure drag that is up to 35% of the viscous drag. or even higher. We utilized a combination of experimental testing and computational fluid dynamics simulations, assisted by optimization methods, to investigate different geometries for the vortex generators and found that the optimal shape was a wedge shaped vortex generator; we then ran several different designs in the MIT Towing Tank on an axisymmetric model to find the optimal vortex generator design for a given speed. Appendix A contains design dimensions of the wedge VGs.

To describe a new method for the automatic generation of process parameters for fused filament fabrication (FFF) across varying machines and materials. We use an instrumented extruder to fit a function that maps nozzle pressures across varying flow rates and temperatures for a given machine and material configuration. We then develop a method to extract real parameters for flow rate and temperature using relative pressures and temperature offsets. Our method allows us to successfully find process parameters, using one set of input parameters, across all of the machine and material configurations that we tested, even in materials that we had never printed before. Rather than using direct parameters in FFF printing, which is time-consuming to tune and modify, it is possible to deploy machine-generated data that captures the fundamental phenomenology of FFF to automatically select parameters.

The integration of artificial intelligence (AI) into the design and fabrication process has opened up novel pathways for producing custom objects and altered the traditional creative workflow. In this article, we present Depthfusion, a novel text-to-3D model generation system that empowers users to rapidly create detailed 3D models from textual or 2D image inputs, and explore the application of text-to-3D models within different fabrication techniques. Depthfusion leverages current text-to-image AI technologies such as Midjourney, Stable Diffusion, and DALL-E and integrates them with advanced mesh inflation and depth mapping techniques. This approach yields a high degree of artistic control and facilitates the production of high-resolution models that are compatible with various 3D printing methods. Our results include a biomimetic tableware set that merges intricate design with functionality, a large-scale ceramic vase illustrating the potential for additive manufacturing in ceramics, and even a sneaker-shaped bread product achieved by converting AI design into a baked form. These projects showcase the diverse possibilities for AI in the design and crafting of objects across mediums, pushing the boundaries of what is traditionally considered feasible in bespoke manufacturing.

Increasing extreme weather events require a corresponding increase in coastal protection. We show that architected materials, which have macroscopic properties that differ from those of their constituent components, can increase wave energy dissipation by more than an order of magnitude over both natural and existing artificial reefs, while providing a biocompatible environment. We present a search that optimized their design through proper hydrodynamic modeling and experimental testing, validated their performance, and characterized sustainable materials for their construction.

We present a robotic system for the assembly of 3D discrete lattice structures in which the robots are able to self-reproduce, such that the assembly system may scale its own parallelization. Robots and structures are made from a set of compatible building blocks, or voxels, which can be assembled and reassembled into more complex structures. Robotic modules are made by combining actuators with a functional voxel, which routes electrical power and signals. Robotic modules then assemble into reconfigurable robots via a reversible solder joint. The robot assembles higher performance structures using a set of construction voxels, which do not contain electrical features. This paper describes the design, development, and evaluation of this assembly system, including the robotic hardware, lattice material, and planning and controls methods. We demonstrate the system through a set of fundamental assembly tasks: the robot assembling another robot, and the two robots collaborating to assemble a small structure.

Several series of experiments were conducted to compare the performance of selected sets of subtractive and additive machine tools for meso-micro machining. Under the MicroCutting Project, meso-micro machining of a reference part was conducted to compare the performance of several machine tools. A prototype flexure of the microspline of an asteroid gripper under development at NASA/JPL was selected as the reference part for the project. Several academic, research institutes, and industrial firms were among the collaborators participating in the project. Both subtractive and additive machine tools were used, including abrasive waterjets, CNC milling, lasers, 3D printing, and laser powder bed fusion. Materials included aluminum, stainless steel, and nonmetal resins. Each collaborator produced the reference part in its facility using materials most suitable for their tools. The finished parts were inspected qualitatively and quantitatively at OMAX Corporation. The performance of the participating machine tools was then compared based on the results of the inspection. Test results show that the two top performers for this test part are the CNC precision milling and micro abrasive waterjet. For machining a single flexure, the CNC precision milling had a slight edge over the micro abrasive waterjet machining in terms ofp art accuracy and edge quality. The advantages disappear or the trend even reverses when stack machining with taper compensation is adopted for the micro abrasive waterjet.

We present a system that transforms speech into physical objects using 3D generative AI and discrete robotic assembly. By leveraging natural language, the system makes design and manufacturing more accessible to people without expertise in 3D modeling or robotic programming. While generative AI models can produce a wide range of 3D meshes, AI-generated meshes are not directly suitable for robotic assembly or account for fabrication constraints. To address this, we contribute a workflow that integrates natural language, 3D generative AI, geometric processing, and discrete robotic assembly. The system discretizes the AI-generated geometry and modifies it to meet fabrication constraints such as component count, overhangs, and connectivity to ensure feasible physical assembly. The results are demonstrated through the assembly of various objects, ranging from chairs to shelves, which are prompted via speech and realized within 5 minutes using a robotic arm.

Laser processing of diamond has become an important technique for fabricating next generation microelectronic and quantum devices. However, the realization of low taper, high aspect ratio structures in diamond remains a challenge. We demonstrate the effects of pulse energy, pulse number and irradiation profile on the achievable aspect ratio with 532 nm nanosecond laser machining. Strong and gentle ablation regimes were observed using percussion hole drilling of type Ib HPHT diamond. Under percussion hole drilling a maximum aspect ratio of 22:1 was achieved with 10,000 pulses. To reach aspect ratios on average 40:1 and up to 66:1, rotary assisted drilling was employed using > 2 M pulse accumulations. We additionally demonstrate methods of obtaining 0.1° taper angles via ramped pulse energy machining in 10:1 aspect ratio tubes. Finally, effects of laser induced damage are studied using confocal Raman spectroscopy with observation of up to 36% increase in tensile strain following strong laser irradiation. However, we report that upon application of 600 °C heat treatment, induced strain is reduced by up to ~ 50% with considerable homogenization of observed strain. Supplementary Information: The online version contains supplementary material available at 10.1007/s00339-023-06755-2.

There has been a proliferation of particle systems developed to model complex systems. These are attractive because they are mesh-free, avoiding issues associated with solver remeshing and convergence. They have however fragmented into niches, using increasingly complex particles that introduce internal degrees of freedom and external solver coupling. We show that, contrary to prior assumptions in the literature, memoryless isotropic point particles can model properties including anisotropy, hysteresis, and failure solely through the statistics of their distributions. The resulting models offer compact code that is straightforward to accelerate and port, can span between micro- and macro-structure, require few parameters to set up a simulation, and unlike high-dimensional machine learning models they use a low-dimensional representation that can be efficiently learned. Rather than deriving them as approximations to either molecular dynamics or partial differential equations we investigate how these models can be found directly, and illustrate this with both qualitative comparisons of phenomenology and quantitative comparisons of predictions.

In this study, we present a method to construct meter-scale deformable structures for underwater robotic applications by discretely assembling mechanical metamaterials. We address the challenge of scaling up nature-like deformable structures while remaining structurally efficient by combining rigid and compliant facets to form custom unit cells that assemble into lattices. The unit cells generate controlled local anisotropies that architect the global deformation of the robotic structure. The resulting flexibility allows better unsteady flow control that enables highly efficient propulsion and optimized force profile manipulations. We demonstrate the utility of this approach in two models. The first is a morphing beam snake-like robot that can generate thrust at specific anguilliform swimming parameters. The second is a morphing surface hydrofoil that, when compared with a rigid wing at the same angles of attack (AoAs), can increase the lift coefficient up to 0.6. In addition, in lower AoAs, the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mi>L</mml:mi> <mml:mo class="MathClass-bin">∕</mml:mo> <mml:mi>D</mml:mi> </mml:math> ratio improves by 5 times, whereas in higher angles it improves by 1.25 times. The resulting hydrodynamic performance demonstrates the potential to achieve accessible, scalable, and simple to design and assemble morphing structures for more efficient and effective future ocean exploration and exploitation.

An adiabatic quantum flux parametron (AQFP) is a two-terminal superconducting device capable of amplifying or inverting digital input signals at near-kT energy dissipation. This ultra-low power device is desirable for myriad reasons, including high performance accelerator applications as CMOS processors become more and more limited by energy consumption. Promising performance results have been realized on AQFP processors; however, scaling these results to larger computing systems faces engineering challenges due to device density and power distribution. AQFP circuits require a multi-phase activation signal to propagate logic. If data is not properly aligned with the activation phase, it can be dropped or shifted to an incorrect phase and disrupt circuit operation. This work presents design and simulation of an activation phase synchronizer: a simple circuit that will accept data arriving on any phase and re-align it to a known phase of the subsequent cycle. The phase synchronizer can be useful for mitigating clock skew across clock domains or play an important role in asynchronous design where the arrival time of data may be unknown.

Abstract Plate lattices are high-performance lightweight structures, exhibiting up to twice the yield strength and stiffness compared to truss lattices of similar geometric arrangement and relative density. Although they are of great interest for research and structural engineering applications, their complex manufacturing and assembly processes limit their practical use, with sandwich panels being an exception. This paper presents a novel approach to the design and modular assembly of folded custom 3-dimensional plate lattices as structural corrugations for use in structural engineering and robotics applications. The plate lattice structural corrugation uses a building block strategy and incorporates custom modified unit cells based on the Miura-ori. This transformation involves expanding the top and bottom zig-zag crease lines into facets and orienting them in space. The resulting modified pattern is referred to as the Kirigami Expanded Miura. The unique structure of these lattices not only provides exceptional mechanical performance as static structures, but also allows for the design of anisotropies in their flexural stiffness by alternating between the Maxwell criterion on bending-dominated or stretchdominated cells. These anisotropies can have value differences of up to 24 with the same geometry, making them ideal for robotic morphing applications. We validate our proposed technology by characterizing the mechanical performance of this new building system and comparing it with state-of-the-art corrugations. We demonstrate the potential of this approach by designing, manufacturing, and modularly assembling multiple structures and robots with single and double curvature.

We present a collection of tools for building plug-and-play modular physical computing systems that we call Modular-Things. Our tools consist of a set of single purpose embedded devices, a link layer agnostic message passing system for communication between devices, and a web-based programming environment. The devices are dynamically discovered and virtualized into software objects that can be programmed in the web IDE. We tested Modular-Things in a classroom setting where groups of novice machine builders constructed custom machines that integrated embedded systems modules with high-level responsive interfaces built with web and computer vision technologies. Users also extended our system by constructing new customized devices.

We present FibeRobo, a thermally-actuated liquid crystal elastomer (LCE) fiber that can be embedded or structured into textiles and enable silent and responsive interactions with shape-changing, fiber-based interfaces. Three definitive properties distinguish FibeRobo from other actuating threads explored in HCI. First, they exhibit rapid thermal self-reversing actuation with large displacements (∼40%) without twisting. Second, we present a reproducible UV fiber drawing setup that produces hundreds of meters of fiber with a sub-millimeter diameter. Third, FibeRobo is fully compatible with existing textile manufacturing machinery such as weaving looms, embroidery, and industrial knitting machines. This paper contributes to developing temperature-responsive LCE fibers, a facile and scalable fabrication pipeline with optional heating element integration for digital control, mechanical characterization, and the establishment of higher hierarchical textile structures and design space. Finally, we introduce a set of demonstrations that illustrate the design space FibeRobo enables.

Computational fabrication relies on time-synchronized operation of various machine components. Designing machines for novel workflows is of interest to the computational fabrication community, but designing control systems for these machines, especially with diverse actuators and sensors, remains challenging. We present MAXL, a modular, extensible machine control architecture that enables synchronous control of heterogeneous components. We contribute (1) a design pattern for a distributed trajectory object with one author and multiple readers, (2) high- and low-level APIs for interfacing this trajectory object to modular hardware and to digital fab applications (3) a simple time-synchronization algorithm and queuing scheme for distributing the trajectory object, and (4) an extensible hardware implementation of MAXL. We demonstrate MAXL’s utility in developing new computational fabrication applications by integrating it into two motion control applications; one for time-synchronized data output (light-painting), and the other for time-synchronized data retrieval (from an accelerometer). Finally, we discuss how MAXL can be extended for use in future machine applications.

Different unmanned aerial system (UAS) applications, such as military reconnaissance, environmental monitoring, or commercial delivery, require different specifications such as payload weight and travel range, which typically require completely different designs. This means that it is difficult, if not impossible, to easily reconfigure an existing UAS for a new application without the redesign and reconstruction of the system. To facilitate easy reconfiguration of UAS, we present Voxelcopter, a modular construction kit for the rapid-prototyping and rapid assembly of multicopter UAS. We develop basic viable components for flight, including reconfigurable building blocks, termed functional voxels, that assemble into high-stiffness, lightweight structures with integrated power and data, a custom flight controller software library, propellers, and power storage. In this demo, a quadcopter is assembled, and we flight test the resulting vehicle, then disassemble it into components ready for reuse, demonstrating the easy reconfigurability of the system.

Abstract Traces of heavy metals found in water resources, due to mining activities and e-waste discharge, pose a global threat. Conventional treatment processes fail to remove toxic heavy metals, such as lead, from drinking water in a resource-efficient manner when their initial concentrations are low. Here, we show that by using the yeast Saccharomyces cerevisiae we can effectively remove trace lead from water via a rapid mass transfer process, called biosorption, achieving an uptake of up to 12 mg lead per gram of biomass in solutions with initial lead concentrations below 1 part per million. Through spectroscopic analyses, we found that the yeast cell wall plays a crucial role in this process, with its mannoproteins and β-glucans being the key potential lead adsorbents. Furthermore, by employing nanomechanical characterization in the yeast biomass, we discovered that biosorption is linked to an increase in cell wall stiffness. These findings open new opportunities for using environmentally friendly and abundant biomaterials for advanced water treatment targeting emerging contaminants.

Abstract Modular robotic systems built of reconfigurable components offer an efficient and versatile alternative to traditional monolithic robots. However, as modular systems scale up, construction efficiency is compromised due to an increase in travel time and path planning complexity. Here we introduce a discrete modular material-robot system that is capable of serial, recursive (making more robots), and hierarchical (making larger robots) assembly. This is accomplished by discretizing the construction into a feedstock of simple primitive building blocks which can be re-configured to create a wide range of functionality. The discretization significantly simplifies the swarm’s navigation, error correction, and coordination. The component composition is supported by an algorithm to compile the building blocks into swarms and plan the optimal construction path. Our approach challenges the convention that larger constructions need larger machines to build them, and could be applied in areas that today either require substantial capital investments for fixed infrastructure or are altogether unfeasible.

Emissions from a dry bulk vessel operating on a biofuel blend were measured. Although marginal differences were observed in CO 2 emissions from combustion compared to conventional marine fuels, life cycle CO 2 emissions can be reduced by up to 40%.

We introduce a modular construction kit for rapidly assembling multi-copter unmanned aerial systems (UAS). The kit consists of voxelized building blocks based on a discrete, face-baced decomposition of a cuboctahedral lattice using a circuit board substrate. These voxel building blocks provide the structure of the vehicle, but also create electrical connections for routing power as well as command and control signals. Functional modules including propulsors, power storage, and command and control are designed to interface with the cuboctahedral lattice to create a complete vehicle. We use the system to assemble a 2.6 kg quadcopter UAS in 22 minutes, flight test the resulting vehicle, then disassemble it into components ready for reuse. We examine how the system scales to larger designs, and compare build times and performance with a comparable commerical UAS and equivalent designs built using additive manufacturing.

We present an open-source, web-based, client-side editor for parametric printed circuit board (PCB) design which supports bidirectional editing between our JavaScript hardware description language and a direct manipulation graphical interface. We developed a JSON format for describing component pads as SVG path data strings, referential component placements, and wire descriptions with curves, arbitrary degree Bezier splines, fillets, and chamfers. Boards can be exported in their JavaScript representation, as SVGs, or in Gerber format. The web-editor also supports interactive elements which update PCB designs in real-time such as number sliders, component translation handles, and drag-and-drop component libraries. Our tool was successfully used for developing and sharing basic boards in a distributed global class on digital fabrication and by researchers to produce procedurally generated designs. SVG-PCB offers the power and flexibility of a general purpose programming language for designing boards with the ease of use of a graphical user interface.

Computational fabrication has enabled the widespread adoption of rapid-prototyping. There has however been a much higher barrier to entry to make a machine. We investigate rapid-prototyping of rapid-prototyping, so that designing a machine can become as accessible as producing projects on one. We characterize minimum viable components for machine building, including "controllerless" designs that virtualize low-level controls in high-level parallel software, simplified systems for force transmission, and tradeoffs in structural systems. In this demo, a machine controlled entirely by a Python application on a host laptop is presented, with communication between the host and the machine at kHz rate. User interaction is enabled by including polling of input modules in the loop. The machine’s behavior is entirely software-defined within the host application, and new modules can be dynamically plugged in with no reconfiguration on the firmware side.

Datasets generated and analyzed during the Pb biosorption study, including yeast growth curve, HPLC data from yeast washing, ICP-MS data for adsorption isotherm, kinetics, chitin, and pH experiments, as well as data from the XPS and FTIR analyses.

Dataset generated and analyzed during the Pb biosorption study, including yeast growth curve, HPLC data from yeast washing, ICP-MS data for adsorption isotherm, kinetics, chitin, and pH experiments, as well as data from the XPS and FTIR analyses.

Datasets generated and analyzed during the Pb biosorption study, including yeast growth curve, HPLC data from yeast washing, ICP-MS data for adsorption isotherm, kinetics, chitin, and pH experiments, as well as data from the XPS and FTIR analyses.

Abstract Traces of heavy metals found in water resources, due to mining activities and e-waste discharge, pose a global threat. Conventional treatment processes fail to remove toxic heavy metals, such as lead, from drinking water in a resource-efficient manner when their initial concentrations are low. Here, we show that by using the yeast Saccharomyces cerevisiae we can effectively remove trace lead from water via a rapid mass transfer process, achieving an uptake of up to 12 mg lead per gram of biomass in solutions with initial lead concentrations below 1 part per million. We found that the yeast cell wall plays a crucial role in this process, with its mannoproteins and β-glucans being the key potential lead adsorbents. Furthermore, we discovered that biosorption is linked to a significant increase in cell wall stiffness. These findings open new opportunities for using environmentally friendly and abundant biomaterials for advanced water treatment targeting emerging contaminants. One-Sentence Summary Removing toxic heavy metals from water at challenging trace levels in an environmentally friendly, resource-efficient manner.

Classes involving physical making were severely disrupted by COVID-19. As workshops, makerspaces, and fab labs shut down in Spring 2020, instructors developed new models for teaching physical prototyping, electronics production, and digital fabrication at a distance. Instructors shipped materials and equipment directly to students, converted makerspaces to job-shops, and substituted low-tech construction methods and hobbyist equipment for industrial tools. The experiences of students and instructors during the pandemic highlighted new learning opportunities when making outside the makerspace. Simultaneously, the shutdown raised new questions on the limits of remote learning for digital fabrication, electronics, and manual craft. This panel brings together experts in making to discuss their experiences teaching physical production in art, design, and engineering during the pandemic. Panelists will discuss their teaching strategies, describe what worked and what did not, and argue for how we can best support students learning hands-on skills going forward.

Abstract Genomically minimal cells, such as JCVI-syn3.0, offer a platform to clarify genes underlying core physiological processes. While this minimal cell includes genes essential for population growth, the physiology of its single cells remained uncharacterized. To investigate striking morphological variation in JCVI-syn3.0 cells, we present an approach to characterize cell propagation and determine genes affecting cell morphology. Microfluidic chemostats allowed observation of intrinsic cell dynamics resulting in irregular morphologies. The addition of 19 genes not retained in JCVI-syn3.0 generated JCVI-syn3A, which presents significantly less morphological variation than JCVI-syn3.0. We further identified seven of these 19 genes, including two known cell division genes ftsZ and sepF and five genes of unknown function, required together to restore cell morphology and division similar to JCVI-syn1.0. This surprising result emphasizes the polygenic nature of cell morphology, as well as the importance of a Z-ring and membrane properties in the physiology of genomically minimal cells.

We introduce DICE (Discrete Integrated Circuit Electronics). Rather than separately develop chips, packages, boards, blades, and systems, DICE spans these scales in a direct-write process with the three-dimensional assembly of computational building blocks. We present DICE parts, discuss their assembly, programming, and design workflow, illustrate applications in machine learning and high performance computing, and project performance.

Mechanical metamaterials offer exotic properties based on local control of cell geometry and their global configuration into structures and mechanisms. Historically, these have been made as continuous, monolithic structures with additive manufacturing, which affords high resolution and throughput, but is inherently limited by process and machine constraints. To address this issue, we present a construction system for mechanical metamaterials based on discrete assembly of a finite set of parts, which can be spatially composed for a range of properties such as rigidity, compliance, chirality, and auxetic behavior. This system achieves desired continuum properties through design of the parts such that global behavior is governed by local mechanisms. We describe the design methodology, production process, numerical modeling, and experimental characterization of metamaterial behaviors. This approach benefits from incremental assembly, which eliminates scale limitations, best-practice manufacturing for reliable, low-cost part production, and interchangeability through a consistent assembly process across part types.

Cutting it close for radical coupling In principle, electrochemistry is an ideal method for radical coupling: One precursor oxidized at the anode pairs up with a counterpart that has been reduced at the cathode. The trouble is that either or both coupling partners might not stay stable long enough to meet in the middle. Mo et al. resolved this issue by closely spacing the electrodes in a microfluidics platform (see the Perspective by Liu et al. ). They showcase coupling of dicyanobenzene as the cathodic radical precursor with a variety of oxidatively generated partners. Science , this issue p. 1352 ; see also p. 1312

Several series of experiments were conducted to compare the performance of selected sets of subtractive and additive machine tools for meso-micro machining. Under the MicroCutting Project, meso-micro machining of a reference part was conducted to compare the performance of several machine tools. A prototype flexure of the microspline of an asteroid gripper under development at NASA/JPL was selected as the reference part for the project. Several academic, research institutes, and industrial firms were among the collaborators participating in the project. Both subtractive and additive machine tools were used, including abrasive waterjets, CNC milling, lasers, 3D printing, and laser powder bed fusion. Materials included aluminum, stainless steel, and nonmetal resins. Each collaborator produced the reference part in its facility using materials most suitable for their tools. The finished parts were inspected qualitatively and quantitatively at OMAX Corporation. The performance of the participating machine tools was then compared based on the results of the inspection. Test results show that the two top performers for this test part are the CNC precision milling and micro abrasive waterjet. For machining a single flexure, the CNC precision milling had a slight edge over the micro abrasive waterjet machining in terms of part accuracy and edge quality. The advantages disappear or the trend even reverses when stack machining with taper compensation is adopted for the micro abrasive waterjet.

In this video, we consider recognition and reconfiguration of lattice-based cellular structures by very simple robots with only basic functionality. The underlying motivation is the construction and modification of space facilities of enormous dimensions, where the combination of new materials with extremely simple robots promises structures of previously unthinkable size and flexibility. We present algorithmic methods that are able to detect and reconfigure arbitrary polyominoes, based on finite-state robots, while also preserving connectivity of a structure during reconfiguration. Specific results include methods for determining a bounding box, scaling a given arrangement, and adapting more general algorithms for transforming polyominoes.

We present a material–robot system consisting of mobile robots that can assemble discrete cellular structures. We detail the manufacturing of cuboctahedral unit cells, termed voxels, which passively connect to neighboring voxels with magnets. We then describe “relative” robots that can locomote on, transport, and place voxels. These robots are designed relative to and in coordination with the cellular structure—the geometry of the voxel informs the robot's global geometric configuration, local mechanisms, and end effectors, and robotic assembly features are designed into the voxels. We describe control strategies for determining build sequence, robot path planning, discrete motion control, and feedback, integrated within a custom software environment for simulating and executing a single or multi-robot construction. We use this material–robot system to build several types of structures, such as one-dimensional (1-D) beams, 2-D plates, and 3-D enclosures. The robots can navigate and assemble structures with minimal feedback, relying on voxel-sized resolution to achieve successful global positioning. We show a multi-robot assembly to increase the throughput and expand system capability using a deterministic centralized control strategy.

We introduce a discrete approach to robotic construction that enables the integration of structure, mechanism, and actuation and offers a promising route to on-demand robot fabrication. We demonstrate this with the assembly of a centimeter-scale Discretely Assembled Walking Motor (DAWM) capable of producing large scale linear or rotary motion from five millimeter-scale part types. The five part types each embody a limited capability including rigid (strut and node), flexural, magnetic, or coil. Through their arrangement in a three-dimensional lattice, we demonstrate the assembly of actuated mechanical degrees-of-freedom in a useful small-scale machine. This work extends prior research in discrete material systems with the inclusion of flexural and actuation components. Actuation is accomplished with the use of voice coil actuator components that produce up to 42mN of force and strokes of 2mm. This performance compares well with other millimeter scale actuators and provides sufficient force to lift 28 connected nodes in our assembled lattice, or 7 other actuator components. DAWM is capable of stepping at rates of up to 35Hz, resulting in velocities of up to 25mm/s. Multiple DAWM systems can be stacked to add force and can be driven in-phase or out-of-phase to produce intermittent or continuous force, respectively. This approach to robot fabrication discretizes robotic systems at a much finer granularity than prior work in modular robotics and demonstrates the possibility of assembling useful small-scale machines from a limited set of standard part types.

&lt;p&gt;Assembly of large scale structural systems in space is understood as critical to serving applications that cannot be deployed from a single launch. Recent literature proposes the use of discrete modular structures for in-space assembly and relatively small scale robotics that are able to modify and traverse the structure. This paper addresses the algorithmic problems in scaling reconfigurable space structures built through robotic construction, where reconfiguration is defined as the problem of transforming an initial structure into a different goal configuration. We analyze different algorithmic paradigms and present corresponding abstractions and graph formulations, examining specialized algorithms that consider discretized space and time steps. We then discuss fundamental design trades for different computational architectures, such as centralized versus distributed, and present two representative algorithms as concrete examples for comparison. We analyze how those algorithms achieve different objective functions and goals, such as minimization of total distance traveled, maximization of fault-tolerance, or minimization of total time spent in assembly. This is meant to offer an impression of algorithmic constraints on scalability of corresponding structural and robotic design. From this study, a set of recommendations is developed on where and when to use each paradigm, as well as implications for physical robotic and structural system design.&lt;/p&gt;

We describe a method for the manufacturing of metallic lattices with tunable properties through the reversible assembly of building block elements, which we call discrete metal lattice assembly (DMLA). These structures can have sub-millimeter scale features on millimeter scale parts used to assemble structures spanning tens of centimeters, comparable to those currently made with Direct Metal Laser Sintering (DMLS). However, unlike traditional additive manufacturing (AM) methods, the use of discrete assembly affords a number of benefits, such as extensible, incremental construction and being repairable and reconfigurable. We show this method results in large scale (tens of centimeters), ultralight (&lt;10 kg/m3 effective density) lattices which are currently not possible with state of the art additive manufacturing techniques. The lattice geometry used here is a combination of two geometries with quadratic property scaling, resulting in a novel lattice with sub-quadratic scaling.

Honeycomb sandwich panels are widely used for high performance parts subject to bending loads, but their manufacturing costs remain high. In particular, for parts with non-flat, non-uniform geometry, honeycombs must be machined or thermoformed with great care and expense. The ability to produce shaped honeycombs would allow sandwich panels to replace monolithic parts in a number of high performance, space-constrained applications, while also providing new areas of research for structural optimization, distributed sensing and actuation, and on-site production of infrastructure. Previous work has shown methods of directly producing shaped honeycombs by cutting and folding flat sheets of material. This research extends these methods by demonstrating work towards a continuous process for the cutting and folding steps of this process. An algorithm for producing a manufacturable cut-and-fold pattern from a three-dimensional volume is designed, and a machine for automatically performing the required cutting and parallel folding is proposed and prototyped. The accuracy of the creases placed by this machine is characterized and the impact of creasing order is demonstrated. Finally, a prototype part is produced and future work is sketched towards full process automation.

We have previously introduced a femtosecond laser micromachining-based scheme for the fabrication of anisotropic waveguides and isotropic Bragg reflection gratings in lithium niobate for application in future integrated-optic spatial light modulators. In this paper, we depict progress in fabrication and characterization of anisotropic Bragg reflection gratings fabricated in lithium niobate via Type I femtosecond laser-based permittivity modulation. We furthermore depict an electromagnetic analysis of such multilayer grating structures based around coupled-wave theory for thick holographic gratings.

&quot;Understanding&quot; and &quot;learning&quot; are two complementary approaches taken to analyze an unfamiliar time series. Understanding is based on explicit mathematical insight into how systems behave, and learning is based on algorithms that can emulate the structure in a time series. Time series analysis has three goals: forecasting, modelling, and characterization. This chapter focuses on a competition run through the Santa Fe Institute in which participants from a range of relevant disciplines applied a variety of time series analysis tools to a small group of common data sets in order to help make meaningful comparisons among their approaches. It describes the design and the results of this competition and reviews the historical and theoretical backgrounds necessary to understand the successful entries. Global computer networks offer a mechanism for the disjoint communities to attack common problems through the widespread exchange of data and information.

Software is shared through files and libraries, but workflows are not. To be able to share workflows for rapid automation, we developed an extensible environment for running CAD, CAM, and machine control. We present Mods, a browser-based environment for data handling, toolpath planning, and machine execution. Users compose modules (either existing modules or new modules they contribute) into workflows for machine automation sequences in a dataflow environment. The modules themselves run client side, implementing the functions used by the modules (such as toolpath planning algorithms or image analysis) in JavaScript, which runs in the browser. The physical machines are connected to a JavaScript server, which listens to commands from the client over a WebSocket connection. Together, these software modules make up an extensible and simple-to-use alternative to traditional CAD/CAM machine control environments.

When exploring the future of work, most people focus on the jobs that will be replaced by technology, the new jobs created by transformational technologies, the jobs that will be upgraded or downgraded by technology, and key trends, such as the growth of “gig” jobs. Understanding this entire blend is important but incomplete. The discussions are missing a category of work that is at once ancient and new—which we term “self-sufficient production”—making what one consumes at a personal, family, or local level. Today, this category is expanding through the accelerating advances in digital fabrication, and it is notable because although it does not involve traditional employment, it shares many of the attributes of “work.”

Extraterrestrial fabrication of spacecraft by current best-practice manufacturing methods is complicated by the need to integrate thousands of unique parts, each made using a diversity of processes and raw materials. Reducing this complexity could enable exponential space exploration via self-replicating spacecraft (known as Von Neumann probes). We propose a hierarchical model for machine design, based on 13 reversibly-assembled part types, reducing the complexity of machine self-replication and bridging prior work in the areas of in-situ resource utilization (ISRU) and modular robotics. Analogous to amino acids in biological systems, these parts form a basis set for the electronic and mechanical subsystems of an exploratory spacecraft. In simulation we validate representative subsystem designs and develop a hierarchical architecture for the design of mechanisms, actuation, and electronics. By standardizing and modularizing the parts, we drastically reduce the diversity of the required supply chain as well as the minimum viable payload mass. We estimate that a seed launch could contain approximately 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> parts, fit within the envelope of a 3U cubesat, and enable the assembly of over one hundred self-replicating assemblers.

We have previously introduced a femtosecond laser micromachining-based scheme for the fabrication of anisotropic waveguides in lithium niobate for use in a guided-wave acousto-optic spatial light modulator. This spatial light modulation scheme is extensible to off-plane waveguide holography via the integration of a Bragg reflection grating. In this paper, we present femtosecond laser-based direct-write approaches for the fabrication of (1) waveguide in-coupling gratings and (2) volume Bragg reflection gratings via permanent refractive index changes within the lithium niobate substrate. In combination with metal surface-acoustic-wave transducers, these direct-write approaches allow for complete fabrication of a functional spatial light modulator via femtosecond laser direct writing.

Digital fabrication machines (such as laser cutters or 3D printers) can be instructed to produce any part geometry within their application space. However, machines' application spaces are not easily modified or extended. How can we enable the production of application-specific computer-controlled machines by machine building novices? How can we facilitate rapid prototyping of rapid prototyping tools? We propose a novel set of modules, the Cardboard Machine Kit, for the construction of digital fabrication machines. These open-source modules are implemented using cardboard frames, stepper motors, and networked electronics controlled through a Python library. We evaluated the kit both through machine building workshops and by studying the usage of the kit in the wild. In the wild we observed more than 500 novice machine builders who built 125 different machines for 15 different application types. We argue that this breadth demonstrates the efficacy of this modular approach. Finally we discuss the limitations of the Cardboard Machine Kit and discuss how it could inform future machine building infrastructure.

That's the promise, and peril, of the third digital revolution, where anyone will be able to make (almost) anythingTwo digital revolutions--computing and communication--have radically transformed our economy and lives. A third digital revolution is here: fabrication. Today's 3D printers are only the start of a trend, accelerating exponentially, to turn data into objects: Neil Gershenfeld and his collaborators ultimately aim to create a universal replicator straight out of Star Trek. While digital fabrication promises us self-sufficient cities and the ability to make (almost) anything, it could also lead to massive inequality. The first two digital revolutions caught most of the world flat-footed, thanks to Designing Reality that won't be true this time.

We describe an approach for the discrete and reversible assembly of tunable and actively deformable structures using modular building block parts for robotic applications. The primary technical challenge addressed by this work is the use of this method to design and fabricate low density, highly compliant robotic structures with spatially tuned stiffness. This approach offers a number of potential advantages over more conventional methods for constructing compliant robots. The discrete assembly reduces manufacturing complexity, as relatively simple parts can be batch-produced and joined to make complex structures. Global mechanical properties can be tuned based on sub-part ordering and geometry, because local stiffness and density can be independently set to a wide range of values and varied spatially. The structure's intrinsic modularity can significantly simplify analysis and simulation. Simple analytical models for the behavior of each building block type can be calibrated with empirical testing and synthesized into a highly accurate and computationally efficient model of the full compliant system. As a case study, we describe a modular and reversibly assembled wing that performs continuous span-wise twist deformation. It exhibits high performance aerodynamic characteristics, is lightweight and simple to fabricate and repair. The wing is constructed from discrete lattice elements, wherein the geometric and mechanical attributes of the building blocks determine the global mechanical properties of the wing. We describe the mechanical design and structural performance of the digital morphing wing, including their relationship to wind tunnel tests that suggest the ability to increase roll efficiency compared to a conventional rigid aileron system. We focus here on describing the approach to design, modeling, and construction as a generalizable approach for robotics that require very lightweight, tunable, and actively deformable structures.

Interest in additive manufacturing has recently been spurred by the promise of multi-material printing and the ability to embed functionality and intelligence into objects. Here, we present an alternative to additive manufacturing, introducing an end-to-end workflow in which discrete building blocks are reversibly joined to produce assemblies called digital materials. We describe the design of the bulk-material building blocks and the devices that are assembled from them. Further, we detail the design and implementation of an automated assembler, which takes advantage of the digital material structure to restore positioning errors within a large tolerance. To generate assembly sequences, we use a novel CAD/CAM workflow for designing, simulating, and assembling digital materials. Finally, we evaluate the structures assembled using this process, showing that the joints perform well under varying conditions and that the assembled structures are functionally precise.

Rapid‐prototyping processes are being extended to increasingly large scales, including 3D printing from gantries, and robotic arms for cutting, milling and winding. These all use designs that are digital, but materials that are not: they are continuously deposited or removed. Neil Gershenfeld, Matthew Carney, Benjamin Jenett, Sam Calisch and Spencer Wilson of the MIT Center for Bits and Atoms explore the implications of the use of digital materials, reversibly assembled from a discrete set of parts with a discrete set of relative positions and orientations, for applications on scales ranging from aerostructures to geoprinting. Here, they discuss the production of the parts, the modelling of structures made with them, and their automated assembly.

Analog telephone calls degraded with distance; digitizing communications allowed errors to be detected and corrected, leading to the Internet. Analog computations degraded with time; digitizing computing again allowed errors to be detected and corrected, leading to microprocessors and PCs. Manufacturing today remains analog; although the designs are digital, the processes are not. I will present emerging research on digitizing fabrication by coding the construction of functional materials, and explore its implications for programming the physical world.

An Interview with Neil GershenfeldNeil Gershenfeld talks with Jim Euchner about the Internet of Things and the coming revolution in manufacturing.Neil Gershenfeld is a pioneer in understanding the boundary between the digital and physical worlds-how objects become data in the network and how data in the network become objects. The technology from his lab, MIT's Center for Bits and Atoms, has been seen and used in a wide variety of settings, from the Museum of Modern Art in New York and the World Economic Forum to rural Indian villages and innercity community centers. In this interview, he discusses the true nature of the Internet of Things, how distributed fab labs can enable anyone to make almost anything, the power of global knowledge sharing with innovation at the nodes, and the future of manufacturing using digital materials.JIM EUCHNER [JE]: The Internet of Things has become quite a buzzword. I think you define it more precisely than some do. Can you give your definition-what is the Internet of Things and what is it not?NEIL GERSHENFELD [NG]: Sure. I was part of a group that started what became called the Internet of Things. A decade or so ago, a group at MIT was working on embedding Internet protocols into devices and showing that, with a few hundred bytes of code and a dollar a part, you could implement a minimal IP stack. That meant that individual devices could talk to the Internet. So the simplest statement about the Internet of Things is that it means IP embedded in devices.A lot of the things called Internet of Things today are really BITNET of Things, and they're being done by people who don't understand the difference between the BITNET and the Internet. They are ignorant of the underlying architecture. There are a few core architectural principles that make the Internet work that you can apply to embedded devices. After 10 or so years, we've had to reconnect the future with the past concerning those architectural principles.BITNET was a connection of mainframes, and it was a very high barrier to entry. To expand the BITNET, you needed to add another mainframe, and that was a large investment that was centrally managed. Users used terminals connected to the mainframes. It was similar to the old phone system: what a telephone did was defined not by the phone but by the central office switch. Adding a new central office switch was a big investment. One of the core principles that led to the Internet was the concept of what was called end-to-end, which roughly means that what the Internet does is defined by what you connect to it.The Internet transports packets; it uses a common representation for those packets. At the time it was emerging, there were many dissimilar networks, and the Internet settled on a common representation that could travel across them. But the Internet is really defined by what you connect to it, not by its physical construction. The Internet could grow by adding things to the edges, not by changing what was at the center. That enabled people to invent instant messaging and VoIP and video streaming and search engines, not by changing the architecture of the Internet but by innovating at the edges.Now the reason so many of the things called Internet of Things are actually the BITNET of Things is that people think in terms of devices, like a light sensor or a thermostat or a switch, connected to a server that proxies its state to build an application. Manipulation of the sensor can be done through the Internet, but the state of the switch or the light is not contained in the switch or light, it's contained in the remote server. That means that to change the function of the device, you have to change the remote thing, not the local thing. You can't innovate at the edges because you need access to the central controller.To be the Internet of Things in my definition, the light or the switch has to be a full-fledged citizen of the Internet. …

Neil Gershenfeld is a pioneer in understanding the boundary between the digital and physical worlds--how objects become data in the network and how data in the network become objects. The technology from his lab, MIT's Center for Bits and Atoms, has been seen and used in a wide variety of settings, from the Museum of Modern Art in New York and the World Economic Forum to rural Indian villages and inner-city community centers. In this interview, he discusses the true nature of the Internet of Things, how distributed fab labs can enable anyone to make almost anything, the power of global knowledge sharing with innovation at the nodes, and the future of manufacturing using digital materials. JIM EUCHNER [JE]: The Internet of Things has become quite a buzzword. I think you define it more precisely than some do. Can you give your definition--what is the Internet of Things and what is it not? NEIL GERSHENFELD [NG]: Sure. I was part of a group that started what became called the Internet of Things. A decade or so ago, a group at MIT was working on embedding Internet protocols into devices and showing that, with a few hundred bytes of code and a dollar a part, you could implement a minimal IP stack. That meant that individual devices could talk to the Internet. So the simplest statement about the Internet of Things is that it means IP embedded in devices. A lot of the things called Internet of Things today are really BITNET of Things, and they're being done by people who don't understand the difference between the BITNET and the Internet. They are ignorant of the underlying architecture. There are a few core architectural principles that make the Internet work that you can apply to embedded devices. After 10 or so years, we've had to reconnect the future with the past concerning those architectural principles. BITNET was a connection of mainframes, and it was a very high barrier to entry. To expand the BITNET, you needed to add another mainframe, and that was a large investment that was centrally managed. Users used terminals connected to the mainframes. It was similar to the old phone system: what a telephone did was defined not by the phone but by the central office switch. Adding a new central office switch was a big investment. One of the core principles that led to the Internet was the concept of what was called end-to-end, which roughly means that what the Internet does is defined by what you connect to it. The Internet transports packets; it uses a common representation for those packets. At the time it was emerging, there were many dissimilar networks, and the Internet settled on a common representation that could travel across them. But the Internet is really defined by what you connect to it, not by its physical construction. The Internet could grow by adding things to the edges, not by changing what was at the center. That enabled people to invent instant messaging and VoIP and video streaming and search engines, not by changing the architecture of the Internet but by innovating at the edges. Now the reason so many of the things called Internet of Things are actually the BITNET of Things is that people think in terms of devices, like a light sensor or a thermostat or a switch, connected to a server that proxies its state to build an application. Manipulation of the sensor can be done through the Internet, but the state of the switch or the light is not contained in the switch or light, it's contained in the remote server. That means that to change the function of the device, you have to change the remote thing, not the local thing. You can't innovate at the edges because you need access to the central controller. To be the Internet of Things in my definition, the light or the switch has to be a full-fledged citizen of the Internet. It needs to be able to implement services so that you can innovate by what you make the device do, not by changing the thing it's connected to. …

The absence of real-time, detailed, 3D information on the composition of surgical specimens presents an enormous challenge in surgical oncology and pathology.

As �the Internet of Things� takes hold, everyday objects are starting to communicate with each other online -- a linking of the digital and physical worlds that will have profound implications for both.

We introduce composite materials made by reversibly assembling a three-dimensional lattice of mass-produced carbon fiber-reinforced polymer composite parts with integrated mechanical interlocking connections. The resulting cellular composite materials can respond as an elastic solid with an extremely large measured modulus for an ultralight material (12.3 megapascals at a density of 7.2 milligrams per cubic centimeter). These materials offer a hierarchical decomposition in modeling, with bulk properties that can be predicted from component measurements and deformation modes that can be determined by the placement of part types. Because site locations are locally constrained, structures can be produced in a relative assembly process that merges desirable features of fiber composites, cellular materials, and additive manufacturing.

Una nueva revolucion digital esta por llegar, esta vez en la fabricacion. Se basa en las mismas ideas que llevaron a la digitalizacion de la comunicacion y la computacion, pero ahora lo que se esta programando es el mundo fisico, no el virtual. La fabricacion digital permitira a las personas disenar y producir objetos tangibles a la medida, donde y cuando los necesiten. El acceso generalizado a estas tecnologias desafiara los modelos tradicionales de negocio, de asistencia y de educacion

The Milli-Motein (Millimeter-Scale Motorized Protein) is ca chain of programmable matter with a 1 cm pitch. It can fold itself into digitized approximations of arbitrary three-dimensional shapes. The small size of the Milli-Motein segments is enabled by the use of our new electropermanent wobble stepper motors, described in this paper, and by a highly integrated electronic and mechanical design. The chain is an interlocked series of connected motor rotors and stators, wrapped with a continuous flex circuit to provide communications, control, and power transmission capabilities. The Milli-Motein uses off-the-shelf electronic components and fasteners, and custom parts fabricated by conventional and electric discharge machining, assembled with screws, glue, and solder using tweezers under a microscope. We perform shape reconfiguration experiments using a four-segment Milli-Motein. It can switch from a straight line to a prescribed shape in 5 seconds, consuming 2.6 W power during reconfiguration. It can hold its shape indefinitely without power. During reconfiguration, a segment can lift the weight of one but not two segments as a horizontal cantilever.

We describe an inertial measurement device based on an electrodynamically trapped proof mass. Mechanical constraints are replaced by guiding fields, permitting the trap stiffness to be tuned dynamically. Optical readout of the proof mass motion provides a measurement of acceleration and rotation, resulting in an integrated six degree of freedom inertial measurement device. We demonstrate such a device—constructed without microfabrication—with sensitivity comparable to that of commercial microelectromechanical systems technology and show how trapping parameters may be adjusted to increase dynamic range.

A substantial fraction of wasted energy can be recovered by extending insights from the architecture of the Internet to the infrastructure of buildings.

Computer science has served to insulate programs and programmers from knowledge of the underlying mechanisms used to manipulate information, however this fiction is increasingly hard to maintain as computing devices decrease in size and systems increase in complexity. Manifestations of these limits appearing in computers include scaling issues in interconnect, dissipation, and coding. Reconfigurable Asynchronous Logic Automata (RALA) is an alternative formulation of computation that seeks to align logical and physical descriptions by exposing rather than hiding this underlying reality. Instead of physical units being represented in computer programs only as abstract symbols, RALA is based on a lattice of cells that asynchronously pass state tokens corresponding to physical resources. We introduce the design of RALA, review its relationships to its many progenitors, and discuss its benefits, implementation, programming, and extensions

Computer science has served to insulate programs and programmers from knowledge of the underlying mechanisms used to manipulate information, however this fiction is increasingly hard to maintain as computing devices decrease in size and systems increase in complexity. Manifestations of these limits appearing in computers include scaling issues in interconnect, dissipation, and coding. Reconfigurable Asynchronous Logic Automata (RALA) is an alternative formulation of computation that seeks to align logical and physical descriptions by exposing rather than hiding this underlying reality. Instead of physical units being represented in computer programs only as abstract symbols, RALA is based on a lattice of cells that asynchronously pass state tokens corresponding to physical resources. We introduce the design of RALA, review its relationships to its many progenitors, and discuss its benefits, implementation, programming, and extensions

Programmable matter is a digital material having computation, sensing, and actuation capabilities as continuous properties active over its whole extent. To make programmable matter economical to fabricate, we want to use electromagnetic direct drive, rather than clockwork, to actuate the particles. Previous attempts to fabricate small scale (below one centimeter) robotic systems with electromagnetic direct-drive have typically run into problems with insufficient force or torque, excessive power consumption and heat generation (for magnetic-drive systems), or high-voltage requirements, humidity sensitivity, and air breakdown. (for electrostatic-drive systems) The electropermanent magnet is a solid-state device whose external magnetic flux can be stably switched on and off by a discrete electrical pulse. Electropermanent magnets can provide low-power connection and actuation for programmable matter and other small-scale robotic systems. The first chapter covers the electropermanent magnet, its physics, scaling, fabrication, and our experimental device performance data. The second introduces the idea of electropermanent actuators, covers their fundamental limits and scaling, and shows prototype devices and performance measurements. The third chapter describes the smart pebbles system, which consists of 12-mm cubes that can form shapes by stochastic self-assembly and self-disassembly. The fourth chapter describes the millibot, a continuous chain of programmable matter which forms shapes by folding. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

Analog logic circuits work on digital problems using an analog representation of the digital variables, relaxing the state space of the digital system from the vertices of a hypercube to the interior. This lets us gain speed, power, and accuracy over digital implementations. Logic automata are distributed, scalable and programmable digital computation media with local connections and logic operations. Here we propose analog logic automata (ALA), which relax binary constraints on logic automata states and introduce programmability into analog logic circuits. The localized interaction and scalability of the ALA provide a new way to do neuromorphic engineering, enabling systematic designs in a digital work flow. Low-power, biomedical, decoding and communication applications are described and a 3times3 ALA chip is prototyped, which works at 50 kHz, with a power consumption of 64 muW. With the chip configured as a programmable noise-locked loop (NLL), we obtain a bit error rate (BER) of 1E-7 at an SNR of -1.13 dB.

We here report on the design of a planar microslot waveguide NMR probe with an induction element that can be fabricated at scales from centimeters to nanometers to allow analysis of biomolecules at nano- or picomole quantities, reducing the required amount of materials by several orders of magnitude. This device demonstrates the highest signal-to-noise ratio for a planar detector to date, measured by using the anomeric proton signal from a 15.6-nmol sample of sucrose. This probe had a linewidth of 1.1 Hz for pure water without susceptibility matching. Analysis of 1.57 nmol of ribonuclease-A shows high sensitivity in one- and two-dimensional NMR spectra. Along with reducing required sample volumes, this integrated geometry can be packed in parallel arrays and combined with microfluidic systems. Further development of this device may have broad implications not only for advancing our understanding of many intractable protein structures and their folding, molecular interactions, and dynamic behaviors, but also for high-sensitivity diagnosis of a number of protein conformational diseases.

We demonstrate universal computation in an all-fluidic two-phase microfluidic system. Nonlinearity is introduced into an otherwise linear, reversible, low-Reynolds number flow via bubble-to-bubble hydrodynamic interactions. A bubble traveling in a channel represents a bit, providing us with the capability to simultaneously transport materials and perform logical control operations. We demonstrate bubble logic AND/OR/NOT gates, a toggle flip-flop, a ripple counter, timing restoration, a ring oscillator, and an electro-bubble modulator. These show the nonlinearity, gain, bistability, synchronization, cascadability, feedback, and programmability required for scalable universal computation. With increasing complexity in large-scale microfluidic processors, bubble logic provides an on-chip process control mechanism integrating chemistry and computation.

No abstract available.

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Jason Taylor, Andrei Florean, Phil Bucksbaum, Neil Gershenfeld; On the Search for Quantum Control of Electronic Spin by Shaped Ultrafast Optical Pulses. AIP Conf. Proc. 15 November 2006; 864 (1): 295–300. https://doi.org/10.1063/1.2400900 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioAIP Conference Proceedings Search Advanced Search |Citation Search

The Internet may be the most complex system ever engineered; from the first host in 1969, it's grown to comprise more than 1 billion routable host addresses (Meng et al., 2005). Its future expansion may be more dramatic still due to the demand to extend the Internet from people to things (Gershenfeld et al., 2004), but the frontiers of high-speed networking have receded further and further from the requirements of small, cheap, slow devices. These things need the Internet's original insights, rather than their current implementation; this is being done in the I0 initiative. The demand for networking embedded devices has led to a proliferation of standards and protocols, including X10, HomePlug, LonWorks, BACnet CEBus, Fieldbus, ModBus, CAN, Lin, I <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> C, SPI, SSI, ASI, USB, EPC, IrDA, Bluetooth, 802.15.4, and ZigBee. While each of these has been optimized for a particular domain, all are encountering many of the same issues that the Internet faced as it grew, including inadequate address space, the need for naming and routing across networks, and mutual incompatibility. This situation is in fact analogous to the early days of the Internet itself

It has been observed that a linear-feedback shift-register (LFSR) sequence can be synchronized by feeding the modulated sequence into a "soft" (or "analog") version of the LFSR. In this correspondence, the "soft LFSR" is derived as forward-only message passing in the corresponding factor graph. A continous-time analog (suitable for realization as a clockless electronic circuit) is then given of both the LFSR and the soft LFSR. A connection is thus established between statistical state estimation and the phenomenon of entrainment of dynamical systems, which opens the prospect of deriving dynamical systems (such as electronic circuits) with strong entrainment capabilities from more powerful message passing algorithms

This project sought fundamental mathematical principles to guide the development of "fungible" computers. Like fungible goods in economics that can be incrementally extended and exchanged, this effort sought to solve problems by using distributed processing nodes propagating mobile code through short-range communications. Motivations for doing this included providing extensibility for hardware to be able to scale with demand, offering reliable operation with unreliable components as process technologies reach fundamental limits, taking advantage of the structure of inherently distributed problems, and dynamically balancing the distribution of computation, storage, sensing, display, and I/O in an operating system. Results included proof-of-principle demonstration applications such as a display that operates statistically, and a unifying research framework based on mathematical programming" that lies at the intersection of physically-inspired local algorithms, graphical message-passing, and global constrained optimization.

Abstract : A paintable computer uses thousands or millions of identical autonomous microsystems. The microsystems are fabricated using a high-volume batch process, mixed with paint and coated onto a surface. Self-assembling code allows the microsystems to act in concert to provide a useful function. MIT staff constructed and programmed a lab-scale prototype paintable display with 1000 semi-autonomous nodes. Also, MIT staff constructed a functional prototype demonstrating power distribution to randomly oriented millimeter scale semiconductor devices. MIT staff performed a series of basic engineering calculations to determine the feasibility of paintable systems with thousands of mm (expn 3) microsystems, including how to power them, manufacture them, and provide communications between them. Based on these calculations, a paintable display, powered by a zinc-air battery for 8 hours, or externally powered by capacitive coupling, appears feasible in principle, with an estimated paint manufacturing cost of $0.40 I cm2 of 0.5 mm resolution color display paint.

We present a printer that builds functional three-dimensional structures by reversible assembly of a discrete set of components, &#x201C;digital materials&#x201D;. This approach uses the components rather than a control system to impose the spatial and functional constraints. Printing can be performed as a parallel rather than a linear process. The printing process is reversible for re-use of the pieces or for error correction at any point in the object's life. Error detection, error-reduction and error-tolerance during assembly allows for reliable, high throughput printing. We are presenting development approaches to such a printing device.

Conventional three-dimensional printing processes are material-dependent, and are irreversible. We present an alternative approach based on three-dimensional assembly of mass-produced two-dimensional components of digital material. This significantly enlarges the available material set, allows reversible disassembly, and imposes constraints that reduce the accumulation of local positioning errors in constructing a global shape. Experimental work on material properties and dimensional scaling of the digital material will be presented, with application in assembling functional structures. We propose that assembling digital material will be the future of 3-dimensional free-form fabrication of functional materials.

THTP, the Trivial Hypertext Transfer Protocol, is an implementation of HTTP over UDP transport. THTP is designed for environments with limited computational power or bandwidth and single-packet exchanges. As such, THTP is best suited for the emerging class of applications running on embedded devices and sensor networks. THTP decouples HTTP from TCP and provides a subset of HTTP's functionality, in particular leveraging HTTP's URI naming scheme. This document describes the THTP protocol.

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008.

Summary form only given. The complete presentation was not made available for publication as part of the conference proceedings.

The historical search for the fundamental meaning of thermodynamic entropy lead to the discovery of the connection between entropy and information about microscopic dynamics, which in turn motivated the development of the theory of information in communications. In this paper I will review how information theory can profitably be applied back to its roots in dynamics in order to characterize the essential properties of a measured time series. Entropy was introduced in the familiar modern form (dS = ffi Q=T ) by Clausius in 1854, building on work by Carnot (1824) and Kelvin (¸1850) to understand the nature of heat and irreversability in thermodynamic systems. 1;2 Boltzmann was dedicated to understanding the microscopic meaning of this macroscopic entropy; influenced by Maxwell&amp;apos;s kinetic theory of gases (¸1860) he introduced the relationship H = R f(r; p; t) log f(r; p; t)d 3 rd 3 p (where f is the velocity distribution in a gas) in 1872, and then the more general form S = k lo...

We've had digital revolutions in communications and computation, but not yet fabrication. Computers control machines that make computers, but a 10-billion-dollar chip fab still uses fundamentally analog materials. Biology provides an alternative model based on programmed assembly of molecular building blocks, offering the same kind of reliability thresholds that enable digital communications and computation. I will present research on fundamentally digital fabrication technologies that merge computation with construction, and illustrate their implications in both developed and developing countries through early access to prototype tools for personal fabrication.

We've had digital revolutions in communications and computation, but not yet fabrication. Computers control machines that make computers, but a 10-billion-dollar chip fab still uses fundamentally analog materials. Biology provides an alternative model based on programmed assembly of molecular building blocks, offering the same kind of reliability thresholds that enable digital communications and computation. I will present research on fundamentally digital fabrication technologies that merge computation with construction, and illustrate their implications in both developed and developing countries through early access to prototype tools for personal fabrication.

What if you could someday put the manufacturing power of an automobile plant on your desktop? According to Neil Gershenfeld, the renowned MIT scientist and inventor, the next big thing is personal fabrication-the ability to design and produce your own products, in your own home, with a machine that combines consumer electronics and industrial tools. Personal fabricators are about to revolutionize the world just as personal computers did a generation ago, and Fab shows us how.

Abstract : This report details the results of the MIT - RF Nixel Program. The RF Nixel Program represents a novel architecture for display systems based on an ensemble of Nixel display elements. Each Nixel element comprises a display element (pixel), lightweight computation sufficient to run self -assembling software code elements and local communications. A proof-of-principle hardware implementation (The Vi .0 Pushpin' Nixel 2D array) was carried out and used to successfully run the gradient and coordinate generating algorithms. Detailed simulation shows the viability of such an approach to render complex text and graphics.

This paper, originally published in 1996, discusses current research on alternative technologies that offer promise for introducing inexpensive, robust and unobtrusive sensing into automobiles. These technologies are based on non-contact detection of material properties and focus on the use of near-field radio frequency measurements to determine the configuration of the occupants. Although this technology can be used for applications such as controlling air bag deployment, they can ultimately help automobiles anticipate and respond to other occupant intentions and needs.

Gershenfeld and Grinstein showed that a modulated linear-feedback shiftregister (LFSR) sequence can be synchronized by feeding the modulated sequence into an analog version of the LFSR. In this paper, a similar algorithm for synchronizing a LFSR sequence disturbed by additive white Gaussian noise is derived as forward-only message passing through the corresponding factor graph.

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2003.

From August 1991 onward, a set of time series was made generally available at the Santa Fe Institute. Several prediction tasks were specified and advertised. The submissions received before the deadline when the true continuations were revealed are analyzed. One result is that connectionist networks, trained with error backpropagation, outperformed the other methods on all series. Among the architectures that performed best was a time delay neural network (also called finite impulse response network) and a recurrent network, designed to capture the multiple time scales present in currency exchange rates.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

While wearable computers are empowering fashion accessories, they bring with them a tangle of wires which connect their parts. As these subsystems begin to decouple and operate on less power, it becomes possible to wirelessly distribute their required data and power using to the wearer's body. We have demonstrated systems that transmit and receive both data and power, and are working to combine the two.

As the power requirements for microelectronics continue decreasing, environmental energy sources can begin to replace batteries in certain wearable subsystems. In this spirit, this paper examines three different devices that can be built into a shoe, (where excess energy is readily harvested) and used for generating electrical power "parasitically" while walking. Two of these are piezoelectric in nature: a unimorph strip made from piezoceramic composite material and a stave made from a multilayer laminate of PVDF foil. The third is a shoe-mounted rotary magnetic generator. Test results are given for these systems, their relative merits and compromises are discussed, and suggestions are proposed for improvements and potential applications in wearable systems. As a self-powered application example, a system had been built around the piezoelectric shoes that periodically broadcasts a digital RFID as the bearer walks.

Modern cryptographic practice rests on the use of one-way functions, which are easy to evaluate but difficult to invert. Unfortunately, commonly used one-way functions are either based on unproven conjectures or have known vulnerabilities. We show that instead of relying on number theory, the mesoscopic physics of coherent transport through a disordered medium can be used to allocate and authenticate unique identifiers by physically reducing the medium's microstructure to a fixed-length string of binary digits. These physical one-way functions are inexpensive to fabricate, prohibitively difficult to duplicate, admit no compact mathematical representation, and are intrinsically tamper-resistant. We provide an authentication protocol based on the enormous address space that is a principal characteristic of physical one-way functions.

When a quantum system interacts with an external environment, it undergoes the loss of quantum correlation (decoherence) and the loss of energy (relaxation) and eventually all of the quantum information becomes classical. Here we show a general principle to use unitary operations to establish and preserve particular non-equilibrium states in arbitrary relaxing quantum systems. We elucidate these concepts with examples of state preservation in one-spin and two-spin entangled systems.

There is a growing sense that the Digital Divide and the role of Information and Communications Technology (ICT) in international development need to be fundamentally reconceptualized. This paper presents the composition and the rationale behind the creation of a network of fabrication laboratories, FAB LABs, whose mission is to provide concrete examples that would lay the foundation for a new framework for this reconceptualization. At the heart of this idea is the belief that the most sustainable way to bring the deepest results of the digital revolution to developing communities is to enable them to participate in creating their own technological tools for finding solutions to their own problems. Each FAB LAB consists of a collection of tools for design and modeling, prototyping and fabrication, instrumentation and testing and debugging, and documentation for a wide range of applications in formal and informal education, health and environmental monitoring, as well as economic and social development.

Cluster-weighted modeling, a mixture density estimator around local models, is presented as a framework for the analysis, prediction and characterization of non-linear time series. First architecture, model estimation and characterization formalisms are introduced. The characterization tools include estimator uncertainty, predictor uncertainty, and the correlation dimension of the data set. in the second part of this chapter the framework is extended to synthesize audio signals and is applied to model a violin in a data-driven input-output approach.

[ring, ring] Alice : Hello…Quantum Computer Associates. Bob : Quantum Computer? Quantum con-puter is more like it! That stuff will never work (other than as a make-work program for underemployed physicists). I wasn't calling for a quantum computer, just a faster one to help me find matches in a

A multi-user, polyphonic sensor stage environment that maps position and gestures of up to four performers to the pitch and articulation of distinct notes is presented. The design seeks to provide multiple players on a stage with the feeling of a traditional acoustic instrument by giving them complete control over the instrument's expressive parameters and a clear causal connection between their actions and the resulting sound. The positions of the performers are determined by a custom ultrasonic tracking system, while hand motions are measured by custom-made gloves containing accelerometer units. Furthermore, juggling clubs are illuminated dynamically to make complex juggling patterns more apparent. The system is currently on tour with the Flying Karamazov Brothers juggling troupe.

A family of remotely interrogated passive temperature sensors is presented. These sensors are comprised of several layers of magnetic materials having either a resonant frequency or harmonic spectrum which varies with temperature. By incorporating a magnetic bias layer and a magnetically permeable layer, it is possible to create sensors which respond to a temperature threshold (reversibly or nonreversibly) or produce a signal which continuously and monotonically varies with temperature. In this paper, a 30%/70% Ni-Fe layer was used in conjunction with amorphous alloy strips to produce three distinct types of wireless temperature sensors operating over the range 20/spl deg/-70/spl deg/C.

To investigate the scaling issues for quantum computation using thermalized ensembles of spins, we are building a rudimentary quantum computer using nuclear magnetic resonance (NMR). We discuss the experimental issues facing the scalability of this technique including the number of qubits, issues of classical versus quantum behavior, and polarization. Due to the weak signals measured in NMR, the most significant challenge to practical devices is polarization enhancement. We present the architecture for a simple NMR spectrometer that is table-top, low-cost, and software-radio driven using commodity electronics and unconventional permanent magnet designs. Optimizations specific to using this machine as a computational device, such as probe design, compilation, and on-line control, are discussed.

Highly durable, flexible, and even washable multilayer electronic circuitry can be constructed on textile substrates, using conductive yarns and suitably packaged components. In this paper we describe the development of e-broidery (electronic embroidery, i.e., the patterning of conductive textiles by numerically controlled sewing or weaving processes) as a means of creating computationally active textiles. We compare textiles to existing flexible circuit substrates with regard to durability, conformability, and wearability. We also report on: some unique applications enabled by our work; the construction of sensors and user interface elements in textiles; and a complete process for creating flexible multilayer circuits on fabric substrates. This process maintains close compatibility with existing electronic components and design tools, while optimizing design techniques and component packages for use in textiles.

We report on a project that explored emerging technologies for intuitive and unobtrusive information interfaces in a compelling setting. An installation at the Museum of Modern Art, New York, was part of a public exhibit and included an interactive table that presented information associated with the exhibit to the gallery visitors without visible conventional computing elements. The enabling devices included noncontact sensing of low-cost tags in physical icons, electrostatic detection of hand location in three dimensions, and sensor fusion through lightweight Internet Protocol access.

The previous MIT Media Laboratory special issue <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> of the IBM Systems Journal closed with a group of papers describing an emerging physical science effort in the Media Lab. These inverted the historical focus of the Media Lab, which was on the revolutionary implications of a digital representation for freeing the content of information from the constraints of its physical representation. When the Media Lab was founded, the debate over the frame size and rate for the next video standard was widely seen as a matter of great significance; the Lab argued instead that a scalable encoding would allow a television set to be downloaded with a TV signal to match the needs of the signal and its viewer. This once-radical idea is now ubiquitous in streaming digital media.

Thesis (Ph.D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2000.

A digital model of a violin/cello is presented that computes violin sounds in real time given gesture input from a violinist. The model is derived from recorded data using clusterweighted sampling, a probabilistic inference technique based on kernel density estimation and wavetable synthesis. Novel interface technology is presented that records gesture input of acoustic instruments and also serves as a standalone controller for digital sound engines. 1 Introduction In this paper, we show how to synthesize the sound of violin-family instruments from a player&amp;apos;s gestural input. The input-output model describes the mapping between physical input time series and a perceptual parameterization of the output time series. It is trained on a recorded data set consisting of gesture input data of the violinist, such as bow and left hand nger position, along with audio output data. The audio signal is reconstructed from the estimated parameterization and from audio samples stored in memory. The...

We present a framework for the analysis and synthesis of acoustical instruments based on data-driven probabilistic inference modeling. Audio time series and boundary conditions of a played instrument are recorded and the non-linear mapping from the control data into the audio space is inferred using the general inference framework of Cluster-Weighted Modeling. The resulting model is used for real-time synthesis of audio sequences from new input data.

This paper demonstrates the use of software radio techniques in the context of sensing, rather than communications. It describes code-division multiplexing (CDMA) and time-division multiplexing (TDMA) of a receiver channel in an electric field sensing system. The only hardware used is a front-end gain stage consisting of two opamps and a microcontroller. The modulation and demodulation operations are implemented entirely in the microcontroller software. Multiple coded waveforms are transmitted simultaneously, and induce a combined signal on a single receive electrode. The combined signal, after passing through a single analog front end terminating in an analog-to-digital converter, is separated into the four original component signals by a software demodulation operation. The signal-to-noise ratio (SNR) achieved by the code-division multiplexed system given a fixed measurement time is compared to the SNR achieved by a time-division multiplexed implementation given the same total measurement time. The paper also compares the scaling of TDMA and CDMA performance with the number of transmitted channels and the number of demodulated channels.

We present an inference-based algorithm for modeling complex non-linear systems, that integrates current approaches to modeling of microwave devices within a generalized framework. Familiar techniques for characterizing linear and non-linear systems are embedded in an automated non-linear weighting mechanism, so that globally complex behavior is approximated by simple local models.

Comprehensive digital analysis and synthesis of musical instruments using direct observations of their physical behavior have been developed and implemented for the violin. In a training session, control input data from unobtrusive bow and finger sensors is recorded simultaneously with the violin’s audio output. These signals are used to train a cluster-weighted probabilistic prediction model that reproduces the nonlinear relationship between the control inputs and the target audio output data. Cluster-weighted modeling was developed to apply previous results from linear systems theory and time-series approximation theory in the broader context of a globally complex and nonlinear model. The presented sound synthesis engine makes use of familiar sound synthesis techniques, but extends them with a complex input/output framework that naturally incorporates dynamic control. The final system predicts audio data based on new control data. While a violinist plays the interface device (a silent violin), the computer model reproduces the sound of the original violin. Recent work has extended the system of sensors and algorithms to model string vibration dynamics as well as the radiated sound.

Information can be stored in inexpensive electronic "tag" microchips which can be embedded in physical objects. We have invented a new tag reader technology which allows information to be transferred into or out of these tag microchips through the human body via touch. Our technology has enabled us to create a novel user interface which can recognize when physical icons are touched, and a wearable system that can inventory packages when they are touched.

The physical user interface is an increasingly significant factor limiting the effectiveness of our interactions with and through technology. This thesis introduces Electric Field Imaging, a new physical channel and inference framework for machine perception of human action. Though electric field sensing is an important sensory modality for several species of fish, it has not been seriously explored as a channel for machine perception. Technological applications of field sensing, from the Theremin to the capacitive elevator button, have been limited to simple proximity detection tasks. This thesis presents a solution to the inverse problem of inferring geometrical information about the configuration and motion of the human body from electric field measurements. It also presents simple, inexpensive hardware and signal processing techniques for making the field measurements, and several new applications of electric field sensing. The signal

This is a book for people who want to know what the future is going to look like and for people who want to know how to create the future. Gershenfeld offers a glimpse at the brave new post-computerized world, where microchips work for us instead of against us. He argues that we waste the potential of the microchip when we confine it to a box on our desk: the real electronic revolution will come when computers have all but disappeared into the walls around us. Imagine a digital book that looks like a traditional book printed on paper and is pleasant to read in bed but has all the mutability of a screen display. How about a personal fabricator that can organize digitized atoms into anything you want, or a musical keyboard that can be woven into a denim jacket? Gershenfeld tells the story of his Things that Think group at MIT's Media Lab, the group of innovative scientists and researchers dedicated to integrating digital technology into the fabric of our lives.

https://works.swarthmore.edu/alum-books/1734/thumbnail.jpg

We show that quantum computation is possible with mixed states instead of pure states as inputs. This is performed by embedding within the mixed state a subspace that transforms like a pure state and that can be identified by labelling it based on logical (spin), temporal, or spatial degrees of freedom. This permits quantum computation to be realized with bulk ensembles far from the ground state. Experimental results are presented for quantum gates and circuits implemented with liquid nuclear magnetic resonance techniques and verified by quantum state tomography.

Using nuclear magnetic resonance techniques with a solution of chloroform molecules we implement Grover's search algorithm for a system with four states. By performing a tomographic reconstruction of the density matrix during the computation good agreement is seen between theory and experiment. This provides the first complete experimental demonstration of loading an initial state into a quantum computer, performing a computation requiring fewer steps than on a classical computer, and then reading out the final state.

The earliest bit-mapped graphical computers have progressed to bring real-time 3D rendering and digital video to the desktop, but the common physical interface remains unchanged from the first workstations. As a result, many applications, such as modeling or navigating in virtual worlds, are often limited not by processing speed but by the users' difficulty in conveying desired actions to the computer. We outline the theory and implementation of low-frequency electric fields as sensing techniques, then present a range of applications developed for interacting with computer graphics.

We present a framework for the analysis and synthesis of acoustical instruments based on data-driven probabilistic inference modeling. Audio time series and boundary conditions of a played instrument are recorded and the non-linear mapping from the control data into the audio space is inferred using the general inference framework of Cluster-Weighted Modeling. The resulting model is used for real-time synthesis of audio sequences from new input data. 1 Introduction Most of today&amp;apos;s musical synthesis is based on either sampling acoustical instruments [Massie, 1998] or detailed first-principles physical modeling [Smith, 1992]. The sampling approach typically results in high sound quality, but has no notion of the instrument as a dynamic system with variable control. The physical modeling approach retains this dynamic control but results in intractably large models when all the physical degrees of freedom are considered. The search for the right combination of model parameters is difficul...

Quantum computation remains an enormously appealing but elusive goal. It is appealing because of its potential to perform superfast algorithms, such as finding prime factors in polynomial time, but also elusive because of the difficulty of simultaneously manipulating quantum degrees of freedom while preventing environmentally induced decoherence. A new approach to quantum computing is introduced based on the use of multiple-pulse resonance techniques to manipulate the small deviation from equilibrium of the density matrix of a macroscopic ensemble so that it appears to be the density matrix of a much lower dimensional pure state. A complete prescription for quantum computing is given for such a system.

The Theremin was one of the first electronic musical instruments, yet it provides a degree of expressive real-time control that remains lacking in most modern electronic music interfaces. Underlying the deceptively simple capacitance measurement used by it and its descendants are a number of surprisingly interesting current transport mechanisms that can be used to inexpensively, unobtrusively, robustly, and remotely detect the position of people and objects. We review the relevant physics, describe appropriate measurement instrumentation, and discuss applications that began with capturing virtuosic performance gesture on traditional stringed instruments and evolved into the design of new musical interfaces. 1)

Bits are bits has been the very successful mantra of the MIT Media Laboratory for its first decade. “Media” has historically meant film vs television vs radio vs newspapers vs books, each of these an entirely separate business, even in a company that does all. In retrospect it is now obvious how artificial it is to categorize information by the package that delivers it. These barriers are now being blown to bits, correctly focusing the interest where it should be: on how to gather, filter, transform, and deliver information to people in a form that is appropriate to the context. Ideas rather than pixels can and should be the primitive unit.

Electronic computers currently have many orders of magnitude more thermodynamic degrees of freedom than information-bearing ones (bits). Because of this, these levels of description are usually considered separately as hardware and software, but as devices approach fundamental physical limits these will become comparable and must be understood together. Using some simple test problems, I explore the connection between the information in a computation and the thermodynamic properties of a system that can implement it, and outline the features of a unified theory of the degrees of freedom in a computer.

A musical instrument is an analog computer. It integrates equations of motion based on applied boundary conditions and generates acoustic and tactile outputs. Understanding why the equations of motion is liked is a very hard problem, fabricating traditional instruments that duplicate desired equations of motion is a hard problem, but using new technology to emulate and generalize them is an increasingly easy problem. The remarkable confluence of sensing, modeling, computing, and communications that is blurring the distinction between using wood and strings or silicon to solve the same equations will be discussed. This includes ideas such as the active remote interrogation of passive structures for sensing, state‐space reconstruction for building observational nonlinear models, cellular automata methods for efficient first‐principles solution of continuum equations, and tools for real‐time computing and communications on general‐purpose platforms.

Share Icon Share Twitter Facebook Reddit LinkedIn Reprints and Permissions Cite Icon Cite Search Site Citation Neil Gershenfeld; Why I Am/Am Not a Physicist. Physics Today 1 July 1995; 48 (7): 50–51. https://doi.org/10.1063/1.2808099 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentPhysics Today Search Advanced Search

We introduce a new class of dynamical systems, analog generalizations of linear feedback shift registers, that can be designed with any number of degrees of freedom, generate optimal pseudorandom noise, and exhibit nonlinear dissipative entrainment which can be used to decode signals in communication and measurement applications.

A non-contact sensor based on the interaction of a person with electric fields for human-computer interface is investigated. Two sensing modes are explored: an external electric field shunted to ground through a human body, and an external electric field transmitted through a human body to stationary receivers. The sensors are low power (milliwatts), high resolution (millimeter) low cost (a few dollars per channel), have low latency (millisecond), high update rate (1 kHz), high immunity to noise (&amp;gt;72 dB), are not affected by clothing, surface texture or reflectivity, and can operate on length scales from microns to meters. Systems incorporating the sensors include a finger mouse, a room that knows the location of its occupant, and people-sensing furniture. Haptic feedback using passive materials is described. Also discussed are empirical and analytical approaches to transform sensor measurements into position information. KEYWORDS: user interface, input device, gesture interface, non-...

A musical instrument is an analog computer. It integrates equations of motion based on applied boundary conditions and generates acoustic and tactile outputs. Understanding why the equations of motion is liked is a very hard problem, fabricating traditional instruments that duplicate desired equations of motion is a hard problem, but using new technology to emulate and generalize them is an increasingly easy problem. The remarkable confluence of sensing, modeling, computing, and communications that is blurring the distinction between using wood and strings or silicon to solve the same equations will be discussed. This includes ideas such as the active remote interrogation of passive structures for sensing, state-space reconstruction for building observational nonlinear models, cellular automata methods for efficient first-principles solution of continuum equations, and tools for real-time computing and communications on general-purpose platforms.

The book is a summary of a time series forecasting competition that was held a number of years ago. The competition used four different kinds of time series (for example, one data set was chaotic from measurements of a laser, and another was a multidimensional physiological times series of heart beats and respiration, etc.). The strength of the book lies in that it represents several ways to approach real time series prediction strategies in a concrete way - Invaluable, especially to researchers who may be just beginning.

This talk surveyed recent progress in forecasting nonlinear time series, including: the breakdown of linear systems theory, nonlinear generalizations by explicit embedding models and implicit neural network models, the role of geometrical invariants in embedding observations, using embedding to build forecasting models, the connection between high- dimensional entropy and dynamics in characterizing nonlinear systems, extension of embedding to more general linear transformations and to its experimental measurement by time-average expectation values, the difference between long-term modeling and short-term forecasting, and strategies for bringing time into connectionist architectures. The details of these techniques, as well as comparisons of their performance on a range of experimental data sets, is available in Time Series Prediction: Forecasting the Future and Understanding the Past, edited by Andreas Weigend and Neil Gershenfeld, Santa Fe Institute Studies in the Sciences of Complexity, Addison-Wesley, August 1993.

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Neil Gershenfeld; Recurring textbook error: Graphs of the hydrogen radial probability density. American Journal of Physics 1 January 1984; 52 (1): 81–82. https://doi.org/10.1119/1.13897 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAmerican Association of Physics TeachersAmerican Journal of Physics Search Advanced Search |Citation Search

An Nth-order linear ordinary differential equation is rewritten as a first-order equation in an N×N matrix. Taking advantage of the matrix manipulation strength of the APL language this equation is then solved directly, yielding a great simplification over the standard procedure of solving N coupled first-order scalar equations. This eases programming and results in a more intuitive algorithm. Example applications of a program using the technique are given from quantum mechanics and control theory.

A new flume is described which contains a rotating laminar flow with a linearly varying temperature distribution from top to bottom, making it useful for a number of model experiments in geophysics. Some experimental results in selective withdrawal from this apparatus are presented as examples of the types of problems that can be addressed.