ERI: Autonomous Personalized Control of Lower Limb Exoskeletons using Impedance Regulation and Trajectory Shaping

San Jose State University Foundation, San Jose CA

Investigators

Abstract

The use of powered exoskeletons to assist persons with physical disabilities and neurological impairments can provide consistent and long-term assistance in comparison to conventional physical therapy methods. Although exoskeletons are now deployed for assistance and rehabilitation, ensuring compliant and flexible interactions between the robot and wearer remains an unresolved issue. Current exoskeletons often do not account for the interaction between the wearer and the robot, relying on pre-planned walking motions. This Engineering Research Initiation (ERI) project aims to spur research into the development of real-time, personalized locomotion strategies for lower limb exoskeletons. The outcomes of this research could lead to safer and more compliant rehabilitation robotic systems. In this project, autonomous locomotion planning and impedance control strategies will be designed and implemented with two challenging purposes: 1) online shaping of personalized walking trajectory to enhance human comfort and 2) real-time adjustment of the exoskeleton impedance during human-robot interaction. Accordingly, intelligent control strategies will be developed for lower-limb exoskeletons to facilitate a balance between exoskeleton autonomy and human safety, which is technically challenging due to the non-passive and unpredictable behaviors of humans that make the detection of their intention and ensuring the flexibility of the exoskeleton's response harder. The control strategies that will be pursued in this research project will advance the trending interdisciplinary research on various lower-limb human robot interaction tasks such as movement therapies, assistive locomotion, and human behavior assessment augmented by an exoskeleton. Accordingly, this research will advance the field of assistive robotics to have a widespread impact on the quality of life for a variety of people with disabilities and neurological conditions caused by spinal cord injury, stroke, and other injuries/diseases. This research has a broader impact to assist occupational workers in performing heavy manual activities with loading on their lower limbs, which will decrease and prevent their primary and secondary injuries. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.