Mardell models a 3D printed top with flexible elastomeric cups
3D printing is perfect for creating items perfectly fit for one person. It has already been applied successfully for prosthetic limbs, joint implants, orthopedic implants and inserts, orthotics, orthodontics, hearing aids, and many more advanced medical applications. Now that people with those rarer conditions have been helped, it’s time for 3D printing to move into applications that help the masses. 75–85% of women who wear bras are wearing the wrong size. By combining 3D scanning, custom software, and 3D printing, millions of women can live more comfortably. I am collaborating with two female industrial designers in Brooklyn who are working on just such a project, and I’m working on exploring a variety of other potential problems and solutions. Using scanning to determine size is very easy, but am taking on the much harder problem of matching and creating the desired curvature and structure. On September 21st, I showed an example design at World Maker Faire in New York that featured 3D-printed elastomeric cups. They are perfectly fit to the wearer using 3D scanning. In this case, the natural shape was ideal, and the function was only to support and preserve, with no shaping required. In cases where a sculpting of form is desired, there is an opportunity for benefit, but a fairly complicated geometry problem to achieve the perfect fit and comfort. I’m making good progress, and this project is tied in with others I’m working on, so expect to hear more about it very shortly.
I have been using an Epilog laser cutter in an unconventional way lately, using it’s raster imaging mode to vaporize materials using repeated passes in an attempt to reproduce fine scale shapes from a “displacement map” image (similar to engraving, just much deeper with predictable dimensions). The most noticeable issue is that, at the 40-watt power level of the machine I am using, the acrylic material is not propelled away from the work surface in the way that high-energy lasers can do. With powerful pulse lasers, very fine cuts can be made in even metals, because the material is instantly vaporized and flies away quickly due to the expansion of the gases. This leaves very little debris at the cut, and does not allow time for the heat to propagate to nearby material, localizing the effects only to the intended area.
You can see the main problem here is that the vaporized material cannot be removed from the area quickly enough. Even with an active vapor-curtain to remove smoke, much of the material still ends up condensing back onto the surface, where it interferes with subsequent passes. There is also some non-linearity in the cut depth (the curvature of the ramp), most likely due to the short focal depth of the laser. This can be compensated for by either shifting the platform upward between passes, or by applying a lookup-table to the gradient to normalize the cutting response. There is also some waviness in the depth that appears to be from vibration in the carriage as it scans over the surface.
Here I attempted a laser-machined acrylic box that needs no assembly, only a heating stage to slump the pieces into position. Note that in addition to the miter-cut edges to join the walls, there are also channels cut in the sides to allow a top to slide into place. After the laser does its work, the acrylic “snow” is cleaned from the piece. It is then flipped over, supported on the inside of the bottom surface, and heated until the walls swing down into position.
3D printing creates perfectly adapted forms with unlimited complexity. It follows that the ideal applications for it should play on its strengths, where using other approaches would be difficult or impossible. One of the major promises of using 3D printing for wearable designs is that is can reduce or eliminate the extensive labor required for assembly. When it comes to functional apparel that integrates wiring, fluid lines, air-flow, mechanical devices or fasteners, having everything produced at once is a huge advantage. The sections can be produced separately so the printer does not have to be the size of a person. Correctly sized, integrated fittings hold the tubes in place.
Body-conforming mesh topology derived from a 3D scan
Some experiments I have in the works are designed to integrate pathways for air/fluid or wiring, and are designed to do so without a lot of manual modeling. The path of the channel is derived from the 3D geometry of the scanned body, so the tubing lines follow the body curvature exactly. There are also some interesting aesthetic possibilities offered by these new structures, which can become part of the design rather than being tacked on top of it or covered by it. The designs are inherently organic. These first attempts look like internal organs more than something produced by a machine.
Inside surface of the tubing study
There are a lot of possibilities for building functional structures using these techniques. The most accessible and easily applied are for cooling and ventilation applications, but after some successful prototypes, the applications will be extended to channels for EL-wire or fiber optic lighting, then wiring, and finally liquids, which I anticipate to be the most challenging. Current production processes for materials that are appropriate structurally also require some access to remove support material, so some advancement in materials, processes, or both must be developed for practical transfer of liquids.