Pelvic motion assistance of NaTUre-gaits with adaptive body weight support

Body weight support (BWS) gait rehabilitation was first introduced in 1987. This method provides a safe and effective environment for gait rehabilitation training. However, the restriction of pelvic motion and body weight shifting are limitations of this method. BWS control strategies focus on providing a precise supporting force for patients. Interaction between the BWS system and a patient as well as pelvic motion guidance are often missing. In this work, a robotic mechanism is designed to provide pelvic motion, with capability of active body weight support. An adaptive control strategy for structural BWS (pa-sBWS) with pelvic motion is introduced to address the issues faced in conventional BWS apparatus. A reference trajectory for pelvic motion is planned and the control strategy will allow the motion of the patient to deviate slightly from the desired trajectory. This method provides an active body weight support to promote the interactive participation of the patient so that the therapeutic outcome will be improved. The control strategy also supports the pelvic motion during the training process. Experiment setup has been used to verify the response of the proposed controller. The experiment results show that the control strategy is able to achieve the objective of this work. The detail of experiments and results are presented at the end of this paper.