A groundbreaking, easy-to-use 3D printable finger prosthesis created by a recent University of Houston graduate could offer amputees a low-cost solution to restore finger functionality. David Edquilang first designed Lunet, which doesn’t need metal fasteners, adhesives or special tools to assemble, as an undergraduate student at the Gerald D. Hines College of Architecture and Design. While standard prostheses can cost thousands of dollars, Edquilang aims to make his design open access on the internet, instead of selling it.
Edquilang explains: “Lunet began when I decided to design and 3D print prototype finger mechanisms for a prosthetic hand for fun in my free time. 2 weeks and 18 prototypes later, I created a mechanism and finger structure that closely replicated the range of motion of real fingers.”
Edquilang’s mentor at UH was Associate Professor Jeff Feng, co-director of UH’s Industrial Design program. Through a partnership with Harris Health System, Feng learned of a patient who had her fingers amputated due to frostbite. Inspired by working on an upper limb prosthesis Edquilang previously developed with student Niell Gorman, working closely with Professor Feng, Edquilang created prosthetic fingers that returned mobility to the patient, allowing her to pick up objects again.
Edquilang continues: “My professor and I were then referred to a finger amputee who lost 3 of her fingers. I applied the mechanism I created to design a finger prosthesis for her. Nearly 40 design iterations and multiple rounds of patient testing were performed to ultimately create a functional prosthesis that fit her.
His “breakthrough” came from a literal break in his design.
“After we finished working with this amputee patient, I continued to tinker with my finger designs. I intentionally broke one of my finger prototypes to see where its structural weakpoint is. It broke at the distal knuckle. This led to me having a breakthrough in the design. I added a linkage that replaces the previously rigid distal knuckle, and I stumbled upon inventing a novel finger mechanism that was more flexible and nearly unbreakable. I then set on refining the design to be more functional, easily 3D printable, and more visually appealing. Inspiration from cyberpunk art and fighter jets influenced the design. 28 design iterations and a myriad of prototypes later resulted in Lunet.”
“It feels great knowing you have the capability to positively impact people’s lives and give them help they otherwise wouldn’t be able to get,” said Edquilang.
“Not every good idea needs to be turned into a business. Sometimes, the best ideas just need to be put out there ,” said Edquilang, who graduated with a Bachelor of Science in Industrial Design last year. “Medical insurance will often not cover the cost of a finger prosthesis, since it is not considered vital enough compared to an arm or leg. Making Lunet available online for free will allow it to help the greatest number of people.”
Lunet wins awards
The prosthetic design garnered Edquilang a 2023 Red Dot: Luminary award, the highest level of recognition accorded at the Red Dot Award: Design Concept. He and Feng took home the coveted accolade at Red Dot’s ceremony last month in Singapore.
“Good results come from dedication. Extraordinary results come from experimentation. Incredible results come from a combination of both,” he said upon winning the award. He has also received a number of other accolades, including iFDesign, and national runner up for the James Dyson Award.
“David’s recent success in winning the most prestigious design awards across the world is the best manifestation of the unparalleled education and training students experience in our Industrial Design program,” Feng said. “Built upon a belief that every student is a creative individual, the program pedagogy focuses on methods of cultivating innovative minds, which is enforced with rigorous professional training.”
Lunet’s geometry inspired its name
Lunet is made up of two common types of 3D printed plastics: polylactic acid and thermoplastic polyurethane. Each finger is made up of four parts held together by plastic pins. Edquilang describes arcs and circular orbits as the foundation for the motion of the finger mechanism. The geometric basis of the design evoked the idea that the prosthesis orbits around the user’s joints like a moon, or lunet, hence the name.
Another element of Lunet’s uniqueness is that it is nearly impossible to break; other finger prosthetics can be complicated and require many parts.
“The problem with higher mechanical complexity is that these designs are less durable,” Edquilang said. “The more parts you have, the more points of failure. You need to make prosthetic fingers robust and as strong as possible, so it doesn’t break under normal use, yet you want the design to be simple. This was one of the greatest challenges in making Lunet.”
He encourages other design students not to be afraid to experiment and fail because that is often how one can learn to improve the most.
“Where the world has an abundance of problems, designers have an abundance of talent, and we should not be selfish with it,” Edquilang said.
Source: University of Houston
