Controller Development of a Passive Control Ankle Foot Orthosis

This article focuses its efforts on the development of passive control foot orthosis featuring magnetorheological (MR) brake actuator. The MR brake was hypothesized as the ideal actuator due to it being able to generate actual braking torque according to the controller's desire. Here, the EMG sensor was utilized as the signal input of the foot movement. Meanwhile, the output of controller was driven to the MR brake in the form of direct current (DC). Fuzzy logic control was employed as the control strategy. The performance of the controller was evaluated experimentally. From the experiment, the controller was observed as able to perform as expectation theorized, measured through the output voltage and sensor inputs. However, the MR brake torque continues to receive little acknowledgement which could be due to insufficient output torque.