Mechatronics

Chapter 6

An Active Orthosis for Gait Rehabilitation ¹

Gait therapy is vital for restoring neuromuscular control in patients suffering from neurological injuries. Robots can provide prolonged, systematic, and repetitive gait training sessions. Currently available robotic devices use stiff actuators with high end point impedance. This work presents a new compliant robotic gait rehabilitation system. Pneumatic muscle actuators (PMAs) were used for actuation purposes. The robotic device is lightweight and works in perfect alignment with patient’s joints. The modeling of robotic device with PMA was performed. Model reference-based adaptive control (MRAC) was used to guide the patient’s limbs on physiological gait patterns, and joint torques required to achieve these trajectories were measured. The PMA with the proposed design is capable of providing the required joint torques. Simulation studies are reported.

6.1. Introduction

6.1.1. Gait rehabilitation

Neurologic injuries such as stroke and spinal cord injuries (SCI) cause damage to neural system and motor function, which results in lower limb impairment and gait disorders. Patients with gait disorders require specific training to regain functional mobility. Traditionally, manual physical therapy has been used for gait rehabilitation of neurologically impaired patients. Body weight-supported (BWS) manually-assisted treadmill training has been in practice for more than 20 years (Figure 6.1) [FIN 91, HES 95, BEH 00]. It allows the ...