Control System for Mobile Cable Tensioning Platform for Rehabilitation of Crouch gait

Abstract

Cerebral palsy (CP) is the main cause of permanent postural and motor abnormalities due to damage to the immature brain of patients in childhood. Patients with cerebral palsy mostly show abnormal gait postures on the sagittal or coronal plane, such as crouch gait or in-toeing, so they should take gait rehabilitation intervention. In this study, we designed a rehabilitation system using a cable attached to each lower limb perpendicular to the sagittal plane of a participant to improve the crouched gait posture. The system contains an actuator and an inelastic cable, a load cell, and a spring for each leg, and uses a fuzzy gain scheduled PID feedback control algorithm to control the cable tension. The newly designed device used a cable-driven mechanism with a minimal number of cables and controlled the magnitude and direction of cable tension by tracking the knee position of participants. We expect less restriction of a voluntary drive of participants with a single cable that maintains perpendicular direction to the sagittal plane during gait compared to existing rehabilitation intervention using a cable-driven mechanism. Additional studies will investigate the effectiveness of the designed system to improve crouch gait with abnormal posture in the coronal plane.