A SECOND CHANCE
“ It is truly inspiring to work with enthusiastic and innovative students in the classroom and the lab and see their ideas and careers take flight .”
— Falko Kuester
and amputee who helped test the devices , says the company could revolutionize access to prosthetics for amputees . “ Mobility is key ,” she says . “ LIMBER can print out a leg in a day , and right away you have a leg to walk on . It ’ s amazing .”
“ Materials for prosthetics have improved dramatically over the last 35 years , from wood to space-age materials to 3D printing ,” say Barrack , a certified prosthetist and orthotist . LIMBER devices are made from water-proof materials — in contrast to traditional prosthetics made of carbon fiber and metal — and are a combination of nylon and nylon filled with chopped carbon fiber . By 3D printing with these two materials , the team can vary the stiffness of the limb , such as by making the foot more or less flexible .
Inspired by Nature
As a structural engineering student at UC San Diego , De Vivo became interested in the connection between natural structures and materials science . He furthered that interest as a doctoral student . He says that the design of the LIMBER prosthesis is inspired by the structure of the Cholla cactus , which has a wooden skeleton that can withstand harsh desert conditions and hurricane-force winds : A cylinder of wooden fibers crisscross at a 45-degree angle with oval spaces between them , like a chain-link fence . This open space allows for optimum flexibility — to bend or rotate in windy conditions — along with increased strength . These naturally
Designed by Nature : LIMBER designs and 3D prints custom prostheses made from cutting-edge materials inspired by the Cholla cactus .
occurring features were incorporated into the design .
UC San Diego Roots
The project started in 2016 in the research group of Falko Kuester , a professor in the Department of Structural Engineering . Dubbed the Limber Integrative Imaging Modeling Manufacturing for Bold Exoskeleton Research project , or LIMBER , the project ’ s goal was to bring together imaging , modeling , simulation testing and 3D printing to create low-cost , one-piece prosthetics that could be tailored specifically to match user needs . Preliminary , proof-of-concept studies with lower-limb amputees demonstrated the potential of this approach . The project was housed in the Qualcomm Institute at UC San Diego .
“ It is truly inspiring to work with enthusiastic and innovative students in the classroom and the lab and see their ideas and careers take flight ,” says Kuester .
Today , LIMBER is part of the medical technology accelerator in the Institute for the Global Entrepreneur ( IGE ) at the UC San Diego Jacobs School of Engineering . It is also part of UC San Diego ’ s Basement startup accelerator . The company will soon start raising a seed round of funding .
Next Steps
LIMBER has now partnered with UC San Diego to raise funds to manufacture 100 prostheses for Ukrainian amputees . This new initiative comes after LIMBER successfully shipped five custom prostheses to Ukraine . •
UC SAN DIEGO MAGAZINE 45