Abstract
In this research, we developed a novel ankle-foot assist device for rehabilitation. This device uses a Stewart Platform Mechanism (SPM) to measure and assist the movements of a human ankle joint in six Degrees Of Freedoms (DOFs). The SPM adapts to the displacement of the rotation axis of a human ankle joint during the movement of a human foot. In our previous work, we have proposed methods of posture measuring and controlling the movement of a human foot. In this study, we propose method of a force control of the device. The force can be controlled by changing the pneumatic pressures in two chambers of each cylinder without using any force sensors. The force control method is tested in experiments for one cylinder and for the developed 6 DOFs assist device. These results suggest that the developed 6 DOFs assist device could be used during ankle-foot rehabilitation without force sensor.
