DEV Community: Eyecontact

Why a large composite 3D printer sped up when a layer was too cold

Eyecontact — Wed, 23 Sep 2026 04:07:35 +0000

An Oak Ridge National Laboratory printer sped up when its deposited plastic became too cold. That correction sounds counterintuitive until the relevant moment is clear: the controller targets the temperature of a layer when the next layer arrives.

The feedback loop

A large-format robotic nozzle extrudes heated plastic composite layer by layer. The material must remain warm enough for one layer to bind to the next, yet cool enough to retain the printed shape. ORNL monitored nozzle position, print speed, and the temperature of dispensed plastic with sensors. Six small thermal cameras around the nozzle watched the deposited material as it cooled.

Computer vision located hot material in the live thermal images and estimated its temperature. When it differed from the target, the controller adjusted print speed so the layer could reach the intended temperature before another was added. This joined observation and correction within the printing process.

What the demonstration established

The team calibrated the controller and six cameras, then printed a hexagon larger than a truck tire. They began at a low speed to challenge the controller. Material was about 30 percent too cool by the next-layer step; the controller raised speed to keep the layers at a temperature suitable for fusion. The print bed lowered slightly as each plastic layer was added.

Earlier ORNL work combined thermal images with statistical models to recognize printing faults. In this demonstration the temperature reading led directly to a speed change during the print. ORNL also says the controller does not need retraining for each new design and was designed for different large-area printers, plastics, and shapes. The reported full-scale trial was the particular hexagon and low-speed start, so performance across those designs remains unmeasured in this article.

Sources:

https://www.ornl.gov/news/error-correction-tech-boosts-3d-printing-big-composite-parts

Reader links:

A Printed Microfluidic Heater Depends on the Layer Between Heat and Liquid

Eyecontact — Wed, 23 Sep 2026 00:20:53 +0000

A thin plastic layer separates the heater from the liquid channel in a microfluidic device introduced by MIT on December 11, 2023. It must transfer heat while preventing liquid from leaking into the resistor. That boundary is a central manufacturing challenge in the team's one-step, multimaterial 3D printing process.

Microfluidic devices manipulate small amounts of fluid and facilitate chemical reactions. Many applications need reactions at particular temperatures. The MIT article describes conventional complex devices made in clean rooms and fitted with gold or platinum heating elements through an expensive, complicated process.

Two materials with a shared base

The researchers used ordinary polylactic acid, or PLA, and PLA containing copper nanoparticles. Ordinary PLA is electrically insulating. Adding copper makes the modified material conductive. When current passes through a resistor made from copper-doped PLA, energy dissipates as heat.

The fabrication method is multimaterial extrusion: several nozzles deposit different materials layer by layer. The team printed the heating resistor first, then printed the microfluidic structure directly above it. Both materials have the same polymer base, similar printing temperatures, and compatible processing conditions.

A continuous barrier with competing requirements

Between the resistor and the microfluidic structure, the printer adds a thin, continuous PLA layer. It must be thin enough for heat to pass from the resistor to the fluid, yet thick enough to prevent leakage into the resistor. The researchers identified manufacturing this layer as especially challenging.

The complete device was printed in one operation without post-assembly. It was about the size of a U.S. quarter and could be produced in minutes. Its channels were approximately 500 micrometers wide and 400 micrometers tall. The reported cost of about $2 refers to materials.

PLA is translucent, leaving the fluid visible. The researchers noted that many chemical processes use visualization or light to infer what is occurring during a reaction.

What the heating result does and does not establish

The prototype could raise the fluid temperature by 4 degrees Celsius between the inlet and outlet. This is a temperature increase across the device. The customizable method could also support particular heating patterns or gradients.

The polymer limits the operating temperature. PLA begins to degrade when heated above about 50 degrees Celsius. The article contrasts this with reactions used in PCR tests, which require 90 degrees Celsius or more.

Precise temperature control would require integrating a third material for temperature sensing. The researchers were also exploring materials that could withstand higher temperatures. These are future development needs alongside the demonstrated heating result.

This case connects material choice to layer placement: the copper-doped polymer provides heat, the channel carries fluid, and the continuous layer between them must transfer heat while preventing leakage. All three are formed within the same printing process.

Sources:

https://news.mit.edu/2023/scientists-3d-print-self-heating-microfluidic-devices-1211

Reader links:

A 3D-Printed Switch Starts With a Polymer That Changes Resistance

Eyecontact — Tue, 22 Sep 2026 22:23:40 +0000

The team discovered its switching material while printing magnetic coils. Active components control electrical signals. In research introduced by MIT on October 15, 2024, a copper-doped polymer supplied a switching behavior that researchers could combine with extrusion 3D printing.

Passing a large current through the material caused its resistance to rise sharply. Shortly after the current stopped, resistance returned to its original level. That reversible observation became the basis for printed resettable fuses and switches without semiconductor materials.

An unexpected result during coil printing

The project began while the team was making magnetic coils with extrusion printing. This process melts filament, pushes it through a nozzle, and builds an object layer by layer. The filament in this case contained copper nanoparticles in a polymer.

Transistors switch on and off to process binary data and form logic gates that perform computation. The printed devices implemented switching functions while remaining well below the performance of silicon-based transistors.

The material combination matters

The team tested other printable polymers containing carbon, carbon nanotubes, and graphene. None of the alternatives they tested functioned as a resettable fuse. The observed result therefore belongs to the copper-doped polymer combination, rather than to conductive filament as a general category.

The researchers proposed two related explanations. Heating by the electric current might spread copper particles apart and increase resistance. Cooling might bring the particles closer again and lower it. They also suggested that the polymer changes from a crystalline to an amorphous state during heating and returns to a crystalline state as it cools.

These explanations remained hypotheses. The resistance change itself was observed, but the proposed account did not fully explain why it occurred only in that material combination. The team explicitly identified that question as needing more research.

From a material response to a printed switch

The devices consist of thin printed traces of the copper-doped polymer. Intersecting conductive regions let the researchers regulate resistance by controlling the voltage supplied to the switch. They used the phenomenon to print switches in a single step that could form semiconductor-free logic gates.

In the experiments, the devices showed no signs of deterioration after 4,000 switching cycles. That is evidence from the reported repeated-operation experiment, not an unlimited service-life rating.

Size and capability remain separate constraints

Extrusion physics and material properties limited how small the switches could become. The team could print devices at a scale of a few hundred microns. The article compared that with transistors in advanced electronics whose diameters are only a few nanometers.

Performance also remained below silicon-based transistors. The article identified simpler control tasks, such as turning a motor on and off, as possible applications. Fully functional printed electronics and a working magnetic motor made only with extrusion printing were future goals.

This work makes a specific manufacturing connection: the same process that places a conductive polymer into a structure can also arrange a material response into a switch.

Sources:

https://news.mit.edu/2024/mit-team-takes-major-step-toward-fully-3d-printed-active-electronics-1015

Reader links:

A Fist-Sized Vacuum Pump Designed Around What a Squeezed Tube Does Next

Eyecontact — Tue, 22 Sep 2026 21:40:47 +0000

A peristaltic pump moves fluid without letting it touch the pump's mechanical parts. Rollers squeeze a flexible tube against a housing as they rotate. Behind each roller, the pinched tube expands again. That expansion creates a vacuum that draws liquid or gas through the tube.

The mechanism is simple to picture, but difficult to shrink for a mass spectrometer. Inside a mass spectrometer, atoms from a sample become ions whose motion is controlled in a vacuum. Collisions with gas molecules alter that motion, reducing analytical specificity and increasing false positives. A portable instrument therefore needs a compact pump that can maintain sufficiently low pressure.

MIT introduced its additive-manufacturing approach on April 25, 2023. The researchers printed a miniature peristaltic vacuum pump about the size of a human fist.

Why more speed and force were poor fixes

When conventional rollers squeeze the tube, its material redistributes under the load. Gaps form and allow leaks. Running the pump faster can move fluid faster than it escapes, but produces excessive heat that damages the pump while leaving the gaps in place.

Applying more force creates another conflict. The mechanism must compress bulged areas to seal the tube fully, and that additional force causes more damage. The design problem was therefore not merely how to squeeze a smaller tube. It was how to stop the tube material from moving into a shape that demanded extra speed and force.

Notches change how the tube deforms

Using a multimaterial 3D printer, the team made the flexible tube from a special hyperelastic material that can withstand large deformation. They then added notches to the tube walls. The notches reduced stress during compression because the material no longer needed to redistribute to counter the rollers' force.

Printing precision allowed the researchers to produce the notch size needed to eliminate the gaps. They also varied wall thickness, strengthening the locations where connectors attach and further reducing stress. Material and geometry addressed different parts of the same failure: repeated deformation and the leaks caused by unwanted redistribution.

One-pass printing still needed temporary support

The entire tube was printed in one pass. This avoided post-assembly defects that could cause leaks. Yet printing a narrow, flexible tube vertically introduced wobble. The researchers printed a lightweight stabilizing structure with it, then peeled that support away without damaging the device.

Reading the performance comparisons correctly

The final design produced a vacuum with pressure one order of magnitude lower than state-of-the-art diaphragm pumps. Lower pressure means a higher-quality vacuum. According to the researcher quoted in the article, standard diaphragm pumps would require three units connected in series to reach the same vacuum.

The pump reached a maximum temperature of 50 degrees Celsius, half the temperature of state-of-the-art pumps used in other studies. It also needed half as much force to seal the tube fully. Earlier in the article, the researchers separately reported pressure one order of magnitude lower than a dry rough pump.

These are bounded comparisons against specified pump types and conditions, not a claim of superiority over every vacuum pump.

The result is a printed miniature pump that addresses leaks, heat, sealing force, and print stability together. Possible portable analysis and Mars-bound survey uses were prospective. The demonstrated device was the pump itself, while the complete miniaturized mass spectrometer was still being developed.

Sources:

https://news.mit.edu/2023/3d-printed-miniature-vacuum-pump-0425

Reader links:

Printing an Electromagnet: Three Materials, Eight Layers, One Functional Geometry

Eyecontact — Tue, 22 Sep 2026 20:48:56 +0000

A doorbell turns electricity into motion with a solenoid. Press the button and current flows through a coil, creating a magnetic field that moves an iron rod into the chime. The principle is familiar. Printing that component in one process is harder because the current path, electrical separation, and magnetic core require different materials to meet without losing their roles.

On February 23, 2024, MIT introduced research on a fully 3D-printed, three-dimensional solenoid made with a modified multimaterial extrusion printer. The result was a component, not an entire device. Its lesson is how material roles, feed mechanics, temperature control, and coil geometry fit together.

Three materials, three jobs

The conductive material forms the coil. Thin dielectric layers serve as insulation between thicker conductive layers. A soft magnetic material forms the central core and improves magnetic performance.

In cross-section, thicker conductive layers alternate with thin insulating layers around that core. The printer stacked them as an eight-layer spiral, comparable to a spiral staircase. Moving upward as well as around the core places more turns within a limited footprint. More turns improve the solenoid's magnetic-field amplification.

The feed system is part of the design

Material selection immediately created hardware constraints. The better-performing soft magnetic nylon contained metallic microparticles in a pliable polymer. It was nearly impossible to make into filament, so the team converted one nozzle to extrude pellets.

The conductive filament began melting early and jammed the nozzle. Ventilation cooled it, while a closer spool holder reduced friction that could damage the thin strand. Dedicated nozzles reduced cross-contamination; four were used because the team tested two soft magnetic materials.

Temperature timing mattered as much as feeding. Each material printed at a different temperature. Depositing the next layer at the wrong moment could smear the materials.

Why eight layers changed the result

The modified printer's precision enabled a solenoid about 33 percent smaller than other 3D-printed versions. The smaller volume could contain more coil turns, while the more effective soft magnetic material improved the core. The printed devices tolerated twice the electric current and generated about three times the magnetic field of other 3D-printed devices.

Those comparison words matter. The baseline was other 3D-printed solenoids, not all conventionally manufactured solenoids. Traditional fabrication still produces a stronger magnetic field.

What “printed in one step” means

The process removed post-assembly between separately made coil, insulation, and core structures, avoiding defects that assembly can introduce. It still required pellet delivery, cooling, spool placement, dedicated nozzles, and synchronized deposition temperatures.

The researchers suggested roles such as power converters in small sensors or actuators in soft robots while pursuing better materials and tighter temperature control.

Sources:

https://news.mit.edu/2024/mit-engineers-3d-print-electromagnets-solenoids-0223

Reader links:

A Polymer-First Route to Electroformed Nickel HIP Cans

Eyecontact — Tue, 22 Sep 2026 20:02:19 +0000

Why start with a plastic shape when the goal is a metal component? In a process developed by Oak Ridge National Laboratory and A.J. Tuck Company, a 3D-printed polymer form supplies the geometry. Electroforming copies that geometry into a nickel shell, and the shell becomes a container for processing metal powder.

Three objects do different jobs: the printed form defines the shape, the hollow nickel HIP can contains the powder, and the final metal component forms when that powder consolidates under heat and pressure. Following these roles explains where 3D printing contributes.

Print the geometry, then build the shell

The team first 3D-prints a polymer mandrel, or form. Polymer additive manufacturing can create complex geometries that would be difficult to produce conventionally. The printed form goes into an electrolyte bath, where electroforming uses electricity to build a dense nickel shell that replicates its surface.

The nickel layer is approximately 2–3 millimeters thick. A.J. Tuck Company provided electroforming and metal-processing expertise and performed the project's electroforming activities.

Once the shell is formed, the polymer is removed. In this project, the team dissolved it with acid, leaving a hollow nickel structure. That empty structure is the HIP can, ready to receive metal powder.

The can enables the next transformation

HIP stands for hot isostatic pressing. In powder metallurgy HIP, metal powder is sealed inside a container and exposed to high heat and pressure. The particles fuse into a fully solid piece close to the desired final shape.

The sequence therefore passes geometry from a printed polymer form to an electroformed shell, then uses the shell to contain powder during consolidation. ORNL's account does not specify the post-HIP treatment of the can.

Why use polymer printing first?

ORNL reports that working with plastic for the initial form reduces material strain and distortion compared with directly printing metal at extremely high temperatures. It also describes lower material and equipment costs, faster design changes, and less post-processing than metal-based additive manufacturing systems. The article gives no numerical cost or time saving for an entire production line.

Conventional HIP-can production involves several fabrication and assembly steps. Here, polymer printing supplies the geometry and electroforming builds the metal container around it. The manufacturing advantage being explored is how these processes work together.

Five cylinders and an integrated port

In phase one, the team electroformed five leak-free cylindrical HIP cans, each 6 inches high and 4 inches in diameter. It also developed an integrated port design that eliminates separate welding of process tubes. The source identifies those separate tube welds as a common source of failure during HIP; the improvement concerns that specific joining step.

Phase two, now underway, will apply the process to a more complex geometry: either an impeller, a rotating component that moves fluid in equipment such as pumps and turbines, or a valve relevant to nuclear energy systems. The demonstrated result is five leak-free cylindrical cans. Extending the process to those complex shapes remains the next stage.

Sources:

https://www.ornl.gov/news/hybrid-process-targets-nuclear-manufacturing-bottlenecks

Reader links:

How 16 3D-Printed Nozzles Produce Uniform Three-Layer Droplets

Eyecontact — Tue, 22 Sep 2026 19:16:36 +0000

How can three liquids remain separate while becoming one microscopic droplet? MIT researchers built a compact electrospray array that guides three non-mixing liquids through concentric nozzles. In tests, its 16 emitters generated uniform droplets with an outer layer, a middle layer, and a core.

The demonstrated result is a fabrication and droplet-generation system. Drug delivery, self-healing materials, biosensors, and artificial cells are proposed applications of the layered particles.

High voltage produces a stream of microdroplets

An electrospray emitter applies high voltage to liquid as it exits a nozzle, producing a steady stream of extremely small droplets. A single emitter has modest output, so an array is needed to increase production without losing uniformity.

Each triaxial emitter contains three concentric nozzles. Three immiscible liquids flow through them simultaneously to form distinct layers in each droplet. The resulting multilayer droplets can solidify into particles with distinct layers.

Coiled channels supply 16 emitters evenly

The array is slightly larger than a U.S. penny and places 16 nozzles in about one square centimeter. Inside, a network of helical microchannels carries liquid to each emitter. This geometry helps maintain uniform spraying while keeping the device compact and limiting interference among neighboring emitters.

Uniformity also depends on alignment. The three concentric nozzles must line up precisely to emit consistent layered droplets. The researchers had to print the tiny channels without support structures that could clog them and remove all uncured resin before operating the device.

Vat photopolymerization creates the internal geometry

The team used vat photopolymerization, which solidifies thin layers of liquid resin with light. They printed layers 25 micrometers tall, enabling the intricate three-dimensional channels and concentric nozzle geometry. The 25-micrometer value describes print-layer height, not droplet diameter.

The one-step fabrication process produced the complex emitter arrays in a few hours. That duration refers to manufacturing the device, not producing an individual droplet.

The middle liquid controls layer stability

The researchers tested several architectures and combinations of liquid flow rates. The viscosity of the middle liquid had the largest role in droplet stability because it preserved the thickness of each layer.

Adjusting flow rates and voltages also changed the thickness of individual droplet layers. This could allow scientists to design drug-delivery particles with layers tailored so medicine releases at the intended time.

The printed array generated uniform three-layer droplets across its emitters. Future work aims to reduce device dimensions further and integrate conductive or dielectric materials. The present advance is the combination of printable microchannels, aligned concentric nozzles, and controlled liquid conditions that lets a compact 16-emitter array produce consistent layered droplets.

Sources:

https://news.mit.edu/2026/3d-printed-devices-could-streamline-drug-delivery-microparticle-production-0609

Reader links:

Why a 3D-Printed Concrete Bridge Broke After Holding 2,000 Pounds

Eyecontact — Tue, 22 Sep 2026 18:20:19 +0000

MIT researchers printed a concrete bridge that supported more than 2,000 pounds across its top with virtually no measurable bending. Afterward, a worker lifted one corner a few inches and it broke. A structure optimized for compression does not automatically tolerate tension.

Concrete responds differently to pushing and pulling

Compression pushes material together, while tension pulls it apart. Concrete performs well in compression and poorly in tension. The researchers designed every part of the bridge to remain in compression under its intended loading condition.

Lifting one corner changed the support and load direction. Parts entered tension they were never designed to carry, causing failure. An optimum for one load is not an optimum for every condition.

Mathematical efficiency must meet printer constraints

The team used topology optimization, which searches for a strong structure using little material. Mathematically efficient, web-like forms can still be impossible for today’s large concrete printers to produce.

The researchers identified three limits: bead thickness, how sharply the nozzle can turn, and the need to print in one continuous line. They put them into the optimization rules so the framework generated a design the machine could fabricate.

On a laptop, the framework produced printable designs in about two minutes. When the bridge size changed on printing day, rerunning it produced an update in five to 10 minutes.

A 2.3-meter bridge tested the calculation

The team printed a 2.3-meter bridge from off-the-shelf mortar in about 30 minutes. The finished structure weighed roughly 900 pounds. In testing, the roughly 900-pound bridge held more than 2,000 pounds spread across it with virtually no measurable bending, closely matching the team’s simulations.

Those results belong to this compression-only geometry and distributed-load test, rather than other support or loading conditions.

The 76 percent figure is a hardware scenario

The bridge used 4-centimeter beads. The analysis found that a machine depositing 1-centimeter beads could reduce material use by as much as 76 percent within safety margins. This models a hardware change, not a reduction already achieved in the bridge.

Bead width had a greater effect than the continuous-path constraint. This finding showed that current printing hardware, rather than concrete strength alone, limited how light the optimized bridge could become.

The researchers are moving toward reinforced concrete because a compression-only structure is not optimal for every load. Feeding rebar into a printed structure remains challenging. The framework incorporated the printer’s fabrication limits directly into the optimization. The bridge test closely matched the simulations, but lifting a corner introduced tension the concrete structure had not been designed to carry.

Sources:

https://news.mit.edu/2026/3d-printed-bridge-points-to-greener-construction-0715

Reader links:

How ShiftLens Changes an Object’s Appearance Without Electronics

Eyecontact — Tue, 22 Sep 2026 17:37:12 +0000

A bottle cap turns, and the bottle changes from a red exclamation mark to a green check. No sensor has read the cap position, and no screen has refreshed. In MIT’s ShiftLens system, the same mechanical motion that tightens the cap shifts two optical layers on the surface.

A lens layer sits over a striped image layer

The upper layer is an array of tiny lenticular lenses. These curved lenses steer light differently according to the viewer’s angle. Underneath is a patterned backplane containing narrow strips from several intended visual states.

When the lens layer moves relative to the backplane, a different set of strips comes into view. The lenses magnify those exposed parts, so the surface appears to show another color, image, or pattern. Instead of changing electronic pixels, ShiftLens changes which printed image strips the lenses reveal.

The user’s normal action drives the change

Mechanical linkages connect an action such as tightening a lid, flipping a switch, or turning a knob to the motion between the optical layers. The display changes as part of using the object. MIT researcher Yunyi Zhu identifies alignment as the central challenge: the optical effect, mechanical linkage, and computational graphics must align with one another.

The design tool handles much of that coordination. A user supplies images for the desired visual states along with the object’s shape and curves. The software then generates a printer-ready ShiftLens structure. Its optical layers and built-in mechanical parts can be manufactured in one pass on a multimaterial 3D printer.

Demonstrations connect motion to visible state

In the bottle demonstration, a securely tightened cap produces a green surface with a check mark. A loose cap produces a red surface with an exclamation mark. This demonstrates a mechanical connection between cap rotation and appearance; it is not a reported test of chemical compatibility or leak detection.

The team also printed a tic-tac-toe game. Turning a knob in different directions makes a square display a red X, a blue O, or no letter. This example shows that one surface can encode more than two visual states.

Motion is a requirement, not an optional detail

ShiftLens does not fit every object. The two optical layers must shift relative to each other. Designers can use motion already present in an object, such as the rotation of a lipstick tube, or add an actuator such as a switch, knob, or roller.

The researchers propose future industrial uses, including piping whose appearance could identify a damaged connection associated with a leak. That is a proposed application, not a reported piping or leak-detection demonstration. The demonstrated contribution is narrower: coordinated optics, mechanics, and generated geometry can let a 3D-printed object display different states through physical interaction alone.

Sources:

https://news.mit.edu/2026/shiftlens-3d-printed-objects-can-tell-you-if-used-properly-0805

Reader links:

Can a 3D-printed recycled-plastic truss support a floor?

Eyecontact — Tue, 22 Sep 2026 16:50:04 +0000

A floor made from printed plastic sounds like a material story. The more useful question is structural: what was printed, how was it arranged, and what did the load test measure?

MIT engineers addressed that question with a floor-truss system printed from recycled PET and glass-fiber pellets. They printed four 8-foot-long trusses, attached them to plywood as a floor frame, and measured deflection while adding weight at the center.

Start with the job of a floor truss

A conventional floor truss uses wood members joined by metal plates. From the side, it resembles a ladder with diagonal rungs that form repeating triangles. Several trusses stand in parallel to support plywood laid across them.

The MIT design targets the same role. Researchers tested several candidate geometries in simulation. Their criterion was stiffness-to-weight ratio: supporting a given load with little deflection while keeping the truss light. For a floor, that means limiting sag between supports.

The best simulated geometry stayed close to a familiar wood-truss pattern. Researchers added small reinforcing elements at each node where a diagonal rung met the main frame. The printable design kept the triangular geometry while reinforcing its connections.

Print four 8-foot-long members

The feedstock combined recycled PET and glass fibers in pellets, a mixture MIT says improves printability and durability. The team fed it as composite “ink” into a room-sized industrial 3D printer.

They printed four trusses, each 8 feet long, 1 foot high, and about 1 inch wide. One took about 13 minutes. The members were then assembled into a 4-by-8-foot floor frame.

The four trusses were spaced in parallel and screwed to plywood. Researchers placed increasingly heavy bags of sand and concrete at the center and measured deflection underneath.

Read the load numbers at the system level

The four-truss floor easily withstood 300 pounds and performed above the U.S. Department of Housing and Urban Development deflection standards cited by MIT. Only after the total load exceeded 4,000 pounds did the trusses buckle and crack.

That 4,000-pound figure belongs to its test configuration. It was not measured for each truss and was not presented as a residential service-load recommendation. It marks when the center-loaded system of four trusses and plywood reached buckling and cracking.

MIT reports that the printed trusses meet existing U.S. building codes in terms of stiffness. The researchers still identify adoption constraints.

Keep the feedstock boundary visible

“Recycled” can hide a major difference in input quality. This material was factory-discarded plastic characterized as exceptionally good recycled feedstock, not dirty post-consumer bottles.

The team is separately testing dirtier inputs, including used soda bottles with liquid residue, to see how contamination changes printed-part quality. Cost is also open: production must compete with wood before wide adoption.

The demonstrated result is specific: recycled PET-and-glass-fiber pellets became four 8-foot-long trusses that were assembled with plywood and loaded to buckling and cracking. Competitive cost and contaminated post-consumer feedstock remain future work.

Sources:

https://news.mit.edu/2026/your-future-home-might-be-framed-with-printed-plastic-0203

Reader links:

Designing Shape Change and Tearing in 3D-Woven Metamaterials

Eyecontact — Tue, 22 Sep 2026 15:54:51 +0000

Can the way a woven lattice tears become a design choice? MIT researchers describe a tool for designing how a lattice changes shape as it stretches, how its fibers entangle and knot, and how it tears at its limit.

The subject is a class of 3D-woven metamaterials: materials whose properties depend primarily on internal microstructure rather than chemical composition. Their building blocks contain intertwined fibers that self-contact and entangle.

Represent placement and connectivity as a graph

The algorithm first represents the metamaterial as a graph. Graph attributes determine where each fiber is placed and how it connects to the others. Woven unit cells form the fundamental building blocks. Design parameters include the radius and pitch of the fibers that make up the woven struts.

Varying these parameters across the structure allows the unit cells to be functionally graded. The framework can tailor one region to be softer and another to be stiffer, or make the structure change shape as it stretches.

Include contact and entanglement in the simulation

The simulation framework predicts deformation response while capturing self-contact within fibers and entanglement. It also supports designing for predicted deformation or tearing patterns and resistance to them. Using the simulations, the team fabricated spatially varying geometries and experimented on them at the microscale.

Turn a manual design task into a reusable tool

The researchers say complex 3D lattices had previously been designed manually, limiting the number of designs tested. They described how woven lattices work and used that description to create a design tool for arbitrary woven lattices. The work demonstrates control and prediction of deformation and failure through geometric tuning, and introduces new building blocks that expand the property space of woven metamaterials.

The released open-source code lets users create designs to fit specifications and generate files for 3D printing or simulation.

Keep the applications in their reported scope

MIT lists possible uses including sensors that move with skin, aerospace or defense fabrics, flexible electronics, and printable textiles. These are proposed applications.

Sources:

https://news.mit.edu/2026/3d-printed-metamaterials-stretch-and-fail-design-0204

Reader links:

Why One Structure Map Is Not Enough for a 3D-Print Preview

Eyecontact — Tue, 22 Sep 2026 14:32:01 +0000

What do depth and Canny edges each contribute to a 3D-print preview? VisiPrint combines a slicer screenshot with a photograph of a printed material exemplar. The screenshot encodes object shape, slicing pattern, and view direction. The exemplar supplies appearance cues such as color and sheen. The pipeline extracts material features, computes geometry and structure guidance, then synthesizes a preview conditioned on both.

Depth and Canny edges preserve different evidence

VisiPrint extracts depth and Canny edges from the slicer screenshot. The depth map preserves global shape and shading. The Canny map preserves slicing patterns and internal contours. The paper's component comparison shows the practical difference: depth alone may blur hollow regions, while edges alone lose shading.

The interface exposes their relative influence through a Slicing Influence control. Higher values emphasize lamination; lower values emphasize shading. The default balances both.

The exemplar brings its lighting with it

A material photograph is evidence and a constraint. VisiPrint inherits the exemplar's lighting and does not support arbitrary relighting. Poor lighting, low contrast, or misalignment in a user-provided image can reduce realism. Users can provide exemplars captured in alternate environments.

The current method is optimized for FDM printing with standard PLA filaments. Complex optical materials, including metallic, translucent, and multicolor filaments, may not be fully captured. Performance on SLA or resin prints was not evaluated. Examples containing sheen or translucency therefore do not establish equal fidelity across every material and printing process.

What the 66.4-second result measured

The user study involved 15 participants. Each participant used VisiPrint, Cura, and Blender for two tasks: visualizing a boat in silver PLA and a whistle in clear PLA. Each task had a five-minute cap. To separate software interaction from asset preparation, VisiPrint participants received the sliced screenshots and the silver and clear PLA reference images in advance.

Under those conditions, participants completed 30 of 30 VisiPrint tasks. For completed tasks, the mean time was 66.4 seconds with a standard deviation of 10.0 seconds. This is a participant workflow result for two prepared tasks. It is not a universal generation-time claim for arbitrary models, material captures, or hardware.

Appearance remains separate from feasibility

VisiPrint previews how an object is likely to look rather than predicting print success. It does not model physical feasibility or support-structure artifacts. It complements slicer checks for supports, adhesion, and print settings; it does not replace them.

The useful result is a bounded workflow: material appearance comes from the exemplar, global shape and shading come from depth, and slicing and internal contours come from Canny edges. Read the appearance preview alongside the slicer's checks for supports, adhesion, and print settings.

This article adapts the evidence and limits from the CHI ’26 paper “VisiPrint: Previewing 3D-Print Appearance from Real Material Samples” by Maxine Perroni-Scharf and coauthors, licensed CC BY 4.0.

Sources:

https://maxineaps.github.io/visiprint-project-site/VisiPrint.pdf

Reader links: