A New Gravity Compensation Mechanism for Lower Limb Rehabilitation

This paper proposes a new mechanical gravity compensation mechanism suitable for the wearable lower limb rehabilitation system. Although the previous gravity compensation systems can also compensate the gravitational moment exerting on each joint perfectly, they are not sufficiently safe if they are applied to the wearable rehabilitation systems because the springs and wires must be barely stretched between the limbs over the joints. In the proposed system, the mechanisms to generate the gravity compensation torques are totally embedded in the link body, so that it can be said that the proposed gravity compensation systems are safer than previous ones. The gravity compensation ability of the proposed mechanism and the effectiveness of the proposed system as a lower limb rehabilitation system are examined by some computer simulations and experiment using the actual equipment.