Problems with the feet can lead to problems with the legs, hips, and back, and problems with the back can lead to problems with the rest of the body, so taking good care of your feet can go a long way towards avoiding a host of health problems. Unfortunately, daily activities such as walking can do a lot of damage without the right kind of shoes – and the right kind of shoes can be hard to find, not to mention expensive. That’s changing with 3D printing, though. The technology has allowed multiple companies to design and manufacture customized shoes and insoles that not only perfectly fit every customer’s feet, but also target trouble spots.
Footprint Footwear (Footprint 3D) is one of those companies. The footwear manufacturer, formed only a couple of years ago, uses 3D printing to create ergonomic yet fashionable shoes tailored to each individual customer. The company works by taking 3D scan data of each customer’s feet and creating specially contoured soles that are designed to provide optimal support and promote a natural gait while walking. Footprint 3D uses Simpleware 3D software to quickly generate lattice structures used in midsoles and insoles, which are then 3D printed with selective laser sintering (SLS) in a TPU powder. The 3D printed TPU is then coated in a polyurethane finish for waterproofing and durability.
The lattice structures, combined with the particle bonding capabilities of the TPU material, allow the energy from wearer’s every step to be dispersed more slowly and evenly, according to early testing. This adds stability while walking and reduces the impact on the body over time.
Using Simpleware, the designers can not only easily generate lattice structures, but can tweak them according to the needs of the wearer. Each pair of shoes is made to order, and can be optimized with help from podiatrists or other foot care professionals.
“Footprint is able to design original soles mapped to a user’s feet and optimize them in Simpleware. The creation of lattice structures based on these original solid .STL files is straightforward and accurate and allows the company to quickly create and modify certain areas of the lattice based on unique foot and gait characteristics. Areas of the sole that need to be more or less flexible, such as the heel and arch areas can be thickened or reduced using Simpleware’s morphological 3D editing tools,” Footprint 3D COO Matthew Flail explains.
Using 3D printing to manufacture the soles also reduces waste and environmental impact, as Footprint Footwear can create a wide range of sizes without ever needing to create molds. This eliminates the scrap material that traditional molding processes create, and a variety of TPU powders can be used, in addition to elastomeric resins for SLA 3D printing systems.
Footprint 3D employs recycling even in its testing processes. Frequently, the designers will remove the soles from an already-manufactured pair of shoes and attach the upper portion of the shoes to a new pair of outsoles and midsoles to test the new sole designs out. Removing the soles is a relatively low-tech process: the shoes are heated in a toaster oven to soften the glue attaching the soles to the uppers, and then the glue is dissolved with acetone so that the soles can be pulled off and the uppers attached to the new ones.
This process saves the company time and money, so that they can dedicate more focus to designing and 3D printing soles that fit each customer perfectly for as much comfort, safety and health as possible. Each person’s feet and gait are unique, so there really is no perfectly fitting shoe without the customization techniques used by Footprint 3D and other companies like them. 3D scanning and 3D printing are making this kind of customization easier, however, so that more people can avoid the kind of foot problems that lead to broader health problems in the future. Discuss in the Footprint forum at 3DPB.com.