Towards active walking from compass gait: stability and hip torque requirement for level ground walking

The aim of this paper is to develop a stable biped model for level ground walking with anthropomorphic parameters. Two models for level ground walking has been simulated and studied, one with active hip joint and the other with ankle impulse. Proposed model is derived from compass gait model with additional torque only at hip joint. Level ground walking has been simulated to find torque requirement and relation between applied torque and angular variation of stance and swing leg. Stability analysis to find disturbance rejection range has also been found. Proposed model serves as a transition from passive walking to energy efficient anthropomorphic walking. Initial stability analysis and model behaviour shows satisfactory results. This concept can be modified towards complete anthropomorphic biped walking by applying minimum possible torque at knee and ankle joint along with hip and also for developing energy efficient active exoskeleton.