Development and Evaluation of a Gait Assistance System Based on Haptic Cane and Active Knee Orthosis

摘要

Post-stroke gait rehabilitation is necessary to aid social re-integration. An active knee orthosis (AKO) can aid gait training through the provision of bodyweight support and assistive knee torque. However, its use may cause instability and it does not ensure improved gait symmetry and speed. Use of a speed regulation device such as a robotic cane in conjunction with and AKO may overcome these limitations. Therefore, to combine the beneficial effects of an AKO and speed regulation, we have devised a gait assistance system (GAS) that combines our developed AKO with our Haptic cane (HC) to provide combined knee assistance and speed regulation. The system can provide constant speed regulation and proprioceptive input to improve gait speed, symmetry and balance, while providing assistive torque to improve knee range of motion. The system is evaluated through tests with nine healthy subjects who wore ankle weights on one leg to simulate hemiparesis. The results show that for majority of the outcome measures (gait and balance parameters), use of the GAS and HC generated significantly better results than use of only the AKO. However, for nearly all the measures there were no significant differences between GAS and HC. Thus, the results indicate that the HC and GAS may be used according to patient's condition, where more severe patients who require assistive torque may use the GAS and less severe patients may use only the HC.