Design of a Device with Non-Interacting Cam Mechanism That Independently Assists Dorsiflexion and Plantarflexion Based on Hip Motion

Stroke patients with muscle weakness and gait disturbances require assistance for inadequate ankle dorsiflexion and plantarflexion movements. This research developed a non- powered walking aid device that assists ankle movements using hip motion as the power source. Unlike systems that rely on active actuators, such as motors, this device employs a cam mechanism and cables to convert the energy from hip flexion and extension movements into dorsiflexion and plantarflexion torques during walking. A study conducted on able-bodied subjects demonstrated that, when assisted by the device, there were significant increases in the ankle joint angle at initial landing, plantarflexion torque in the late stance phase, and dorsiflexion angle in the swing phase. However, a decrease in ankle plantarflexion angular velocity was observed, suggesting that further improvement of the device is needed.