EAPSI: Investigating the Use of Pneumatic Muscles for Better Compliant-Control Rehabilitative Devices

Huynh Samantha, Los Angeles CA

Investigators

Abstract

Hindered by muscular difficulties with control, coordination, tone, and reflex, patients affected by muscular disorders like dystonia are often left voiceless in a world where their minds are just as curious, just as creative, but they lack the ability to exercise expression. Dystonia describes a collection of abnormal states of muscle tone, usually resulting in muscular spasms and abnormal postures. Patients with dystonia often have difficulty in rehabilitation environments, as they are unfamiliar with the correct motor control mechanisms to exercise their bodies as well as suffering from muscular impairments. The exoskeleton provides a platform with which patients can learn correct motor control by using artificial muscles to provide support where necessary. In collaboration with Dr. Tomoyuki Noda, principal investigator and main developer of a series of exoskeletons at the Advanced Telecommunications Research Institute International (ATR) in Japan, this project investigates the development of artificial muscles for use in a rehabilitative exoskeleton to aid those with upper body movement disorders. The objective of this project is to incorporate the advances developed in pneumatic-electric hybrid muscles by Dr. Noda to the prototype exoskeleton compliant-control system currently under evaluation at the University of Southern California's Sanger Lab. The exoskeleton project seeks to provide a viable rehabilitative solution for children diagnosed with dystonia with an emphasis on compliant control. User input via electrical signals from excited muscles, also known as electromyographic (EMG) signals, controls the exoskeleton's actuation, allowing the patient to direct their own movements. The use of pneumatically powered muscles is ideal for this project, as the mechanisms of pneumatic actuators are best adapted for compliance-controlled targets. Just as human muscles exert force under contraction, so do pneumatic muscles. This parallel aids in the current investigation as patients will be using technology that mimics natural movement. As a hands-on endeavor to engage users in their own rehabilitation, the proposed activity stands at the edge of transforming existing parameters for rehabilitative devices and understanding compliant-controlled systems. This award, under the East Asian and Pacific Summer Institutes program, supports summer research by a U.S. graduate student and is jointly funded by the NSF and the Japan Society for the Promotion of Science.