WPAL [52] is a wearable HKA exoskeleton, developed to provide
assistance to people with walking disorders due to aging,
paralysis, or following amputation. WPAL realizes a compliance
control using joint angles, velocities and interaction forces information,
provided by a wide sensory apparatus, including force
sensors on the thigh and lower leg and encoders at each joint. The
controller bases on dynamic models of the WPAL and of the user’s
leg respectively, which are then analyzed synthetically to calculate
demanded torques. Only bench test addressing the system’s compliance
was performed.