Recently, researchers started to engineer not only the outer shape of objects, but also their internal microstructure. Such objects, typically based on 3D cell grids, are also known as metamaterials. Metamaterials have been used, for example, to create materials with soft and hard regions.
So far, metamaterials were understood as materials—we want to think of them as machines. We demonstrate metamaterial objects that perform a mechanical function. Such metamaterial mechanisms consist of a single block of material the cells of which play together in a well-defined way in order to achieve macroscopic movement. Our metamaterial door latch, for example, transforms the rotary movement of its handle into a linear motion of the latch. Our metamaterial Jansen walker consists of a single block of cells—that can walk. The key element behind our metamaterial mechanisms is a specialized type of cell, the only ability of which is to shear.
In order to allow users to create metamaterial mechanisms efficiently we implemented a specialized 3D editor. It allows users to place different types of cells, including the shear cell, thereby allowing users to add mechanical functionality to their objects. To help users verify their designs during editing, our editor allows users to apply forces and simulates how the object deforms in response.
And Prototype 2 is really working nice....
Posted by Fouche 3D Printing on Monday, November 30, 2015
3D printers use as raw material plastic filament of about 360 m long, coiled. With a coil, we can make some items. But when there remain only a few meters, it is often impossible to use it. This filament is then unusable or discarded. Considering the price, it's infuriating.
It also happens that the filament breaks during printing or on the coil.
The current size of the filament coils do not allow to print large parts. The best solution would be to link together the filaments of each coil. Thus, the size of the printable parts would be no more limited.
From these findings, I have sought to develop a plastic filament welder to:
- Print large parts.
- Reduce filament waste.
- Combine different colors and / or filament materials.
- Making life easier for 3D printers.
- Saving money.
The EasyWelder can weld the following plastic filaments:
- PLA
- PVA
- ABS
- HIPS
- NinjaFlex and other similar filaments
- PEG
- Nylon
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| EasyWelder tool and clamp |
TestrBot is a $300 Universal Test Machine (UTM) and can be used to perform any type of static or dynamic testing in tension or compression up to 200 lbs. It was designed to run a gamut of physical tests on 3D printed specimens.
3D printing is still new enough that there are many questions that do not yet have definitive answers. While the basic physical properties of raw ABS & PLA have been well established, there are still many esoteric material properties that cannot be determined without doing actual mechanical testing.
TestrBot is going to help the 3D printing community by figuring out these properties. As of this writing, I am at the beginning of the testing process but you can among the first to hear about the results as they become available by following blog here: www.EngineerDog.com
NEW: added a model for a mouth piece that allow to have a stand alone pick and place tool with no vacuum pump. The tube is a flexible silicon aquarium airline from a pet store. The filter is a universal 1/4" automobile fuel filter (filed to fit the airline).
This is a single piece design a handle for vacuum hand picker for electronics SMT components. It has two versions, one with a release hole and without release hole (I am using the latter with a foot pedal and a 12V pneumatic valve for better release stability).
The printed release hole is intentionally small and you can drill a larger one if you want, or just print the no hole version and drill a hole wherever you want. The handle is compatible with standard industrial blunt needles (available on eBay) and with standard aquarium air hose (use silicon hose for better flexibility, e.g. "TopFin Silicone Airline Tubing").
The files with 'demo' in their name are provided to show the internal details. These are not the files you want to print.
I printed it on a Prusa i3V using PLA, 20% infill, 5 top, bottom and vertical shells (in Slic3r) for better air tightness and no material support (otherwise you will block the internal air passage).
Air tightness is important for proper operation so you want to test it by holding it under water with the tip blocked and blowing into the hose. If you still see bubble through cracks and holes you may want to increase the number of shells, print slower, make sure you don't under extrude or fill the holes with glue (you can apply vacuum to such the glue into the holes).
This is a base design and hopefully others will improve on it. For example, forcing the air to flow near the release hole for minimizing the residual vacuum when released, a built in adjustable valve for regulating the desire lifting force, built in air filter or somehow making this thing ESD safe.
It is a handy tool to convert 3D models from one file format to another (i.e. FBX to OBJ or OBJ to STL for 3D printing, DAE to JSON for use with WebGL, ..).
Supported input file formats include 3DS, FBX, Blender, OBJ, DXF, LWO, STL, PLY and more than 25 others. Output formats include Collada, 3DS, X, OBJ, PLY, STL (Text and Binary), JSON (Assimp2Json) and more. You can upload up to 5 files with a total size of 50 MiB.
This service is forever free.
