Author: u0249796

Lower-limb-powered prostheses can provide users with volitional control of ambulation. To this end, they require a sensing modality that reliably interprets user intention to move. Ultrasound has been shown to have better resolution and specificity than surface EMG. However, this technology has yet to be integrated into lower-limb prostheses. In this paper, we show that A-mode ultrasound sensing can reliably predict the prosthesis walking kinematics of individuals with a transfemoral amputation. Ultrasound features from the residual limb of 9 transfemoral amputee subjects were recorded with A-mode ultrasound during walking with their passive prosthesis. The manuscript is freely available at this...

Torque-sensitive transmissions have emerged as promising solutions to meet this need by significantly increasing actuator efficiency and power density, but their modeling and analysis remain an open research topic. In this paper, we introduce the sensitivity between input displacement and output torque as a key metric to analyze the performance of these complex mechanisms in dynamic tasks. Our results show that sensitivity analysis is a valuable tool for designers to systematically analyze and create transmission systems capable of human-like physical behavior. The manuscript can be downloaded freely at this link: Actuators | Free Full-Text | Analysis and Validation of Sensitivity...

In this study,  we show that varying the assistive knee torque provided by a powered knee prosthesis significantly improved weight-bearing symmetry, effort, and speed during the stand-up movement in eight above-knee amputees. Specifically, we observed improvements in the index of asymmetry of the vertical ground reaction force at the point approximating maximum vertical center of mass acceleration, the integral of the intact vastus medialis activation measured using electromyography, and the stand-up duration compared to the passive prosthesis. These results show that powered prostheses can improve functional mobility, potentially increasing quality of life for millions of people living with above-knee...