The Defense Advanced Research Projects Agency (DARPA) announced that the first program its new Biological Technologies Office will undertake is to restore a sense of touch to upper-limb prosthetic users.
DARPA’s new Hand Proprioception and Touch Interfaces (HAPTIX) program builds on neural-interface technologies advanced during DARPA’s Revolutionizing Prosthetics (RP) and Reliable Neural-Interface Technology (RE-NET) programs that made advancements in providing a direct link between user intent and prosthesis control. HAPTIX aims to achieve its goals by developing interface systems that measure and decode motor signals recorded in peripheral nerves and/or muscles. The program will adapt one of the advanced prosthetic limb systems developed under the RP program to incorporate sensors that provide tactile and proprioceptive feedback to the user, delivered through patterned stimulation of sensory pathways in the peripheral nerve. One of the key challenges will be to identify stimulation patterning strategies that elicit naturalistic sensations of touch and movement. The ultimate goal, DARPA said, is to create a fully implantable device that is safe, reliable, effective, and approved for human use.
In addition to the improved motor performance that restored touch and proprioception would convey to the user, mounting evidence suggests that sensory stimulation in individuals with amputations may provide psychological benefits such as improving prosthesis embodiment and reducing phantom limb pain. For this reason, DARPA said it seeks the inclusion of psychologists in the multidisciplinary teams of scientists, engineers, and clinicians proposing to develop the electrodes, algorithms, and electronics technology components for the HAPTIX system. Teams will need to consider how the use of HAPTIX system may impact the user in several domains including motor and sensory function, psychology, pain, and quality of life.
“We have the opportunity to not only significantly improve an amputee’s ability to control a prosthetic limb, but to make a profound, positive psychological impact,” said Doug Weber, PhD, DARPA’s program manager. “Amputees view existing prostheses as if they were tools, like a wrench, used only to perform a specific job, so many people abandon their prostheses unless absolutely needed. We believe that HAPTIX will create a sensory experience so rich and vibrant that the user will want to wear his or her prosthesis full-time and accept it as a natural extension of the body. If we can achieve that, DARPA is even closer to fulfilling its commitment to help restore full and natural functionality to wounded service members.”
The program plan culminates with a 12-month, take-home trial of the complete HAPTIX prosthesis system. To aid performers in the completion of the steps necessary to achieve regulatory approvals for human trials, DARPA consulted with the U.S Food and Drug Administration (FDA) to incorporate regulatory timelines into the program process.
If it is successful, the HAPTIX program will create fully implantable, modular, and reconfigurable neural-interface microsystems that communicate wirelessly with external modules, such as the prosthesis interface link. Because such technology would have broad application and could fuel future medical devices, HAPTIX also plans to fund teams to pursue the science and technology that would support next-generation HAPTIX capabilities.
For more information on available HAPTIX opportunities, visit the Federal Business Opportunities website.