Research Projects

Dr. Tommaso Lenzi, Dr. Lukas Gabert (post-doctoral fellow), Andrew Gunnel (student)

Ergonomics and Safety

National Robotics Initiative - CMMI-1925371 - T. Lenzi (PI)
National Science Foundation (NSF) - Division of Civil, Mechanical and Manufacturing Innovation (CMMI)
09/1/2019-08/31/2023 -- $600,000

The objective of this project is to enable volitional control over lower-limb prostheses through the integration of sonomyographic sensing -- the ultrasound imaging of amputated (i.e., residual) limb muscle morphology -- to control the Utah Lightweight Leg. This powered prosthetic leg is comprised of powered ankle and knee modules, and is roughly half the weight of contemporary technologies. We are using sonomyographic sensors in combination with mechanical sensors to infer the user's intent in anticipation of ambulation mode or joint motion -- for example, transitions from walking over level ground to ramps or stairs. We are also comparing the ability of participants with transfemoral amputation to ambulate with and without various sonomyographic control algorithms enabled. If successful, the project will have positive impact on national health and welfare by improving the lives of individuals with amputation in terms of their independence and movement abilities, and by mitigating undesirable secondary effects of amputation such as a fear of falling and long-term joint health. Additional broader impacts of the work include enhanced undergraduate and graduate research experiences for veterans and underrepresented minorities, as well as outreach activities to K-12 students.

Publications:

• Powered Knee and Ankle Prosthesis With Adaptive Control Enables Climbing Stairs With Different Stair Heights, Cadences, and Gait Patterns
• Performance of Sonomyographic and Electromyographic Sensing for Continuous Estimation of Joint Torque During Ambulation on Multiple Terrains
• Stand-Up, Squat, Lunge, and Walk With a Robotic Knee and Ankle Prosthesis Under Shared Neural Control
• Effect of Increasing Assistance from a Powered Prosthesis on Weight-Bearing Symmetry, Effort, and Speed during Stand-Up in Individuals with Above-Knee Amputation
• Powered knee and ankle prosthesis with indirect volitional swing control enables level-ground walking and crossing over obstacles