Modeling, Dynamics and Control of an Extended Elastic Actuator in Musculoskeletal Robot SystemIntelligent Autonomous Systems 12

The conventional actuator of robot needs to be improved since the bandwidth of motor is limited and it cannot provide enough flexibility to perform the compliance in robot locomotion interacted with environment. In this paper, we present a novel elastic actuator so as to enhance the range of robot activities for adaptability. Considering the characteristics of elasticity and the demands in reality, a feasible study model is developed and constructed. According to the theory of Newton-Euler dynamics equations, the dynamics of model is mathematically described. To avoid unpredictable errors and manage joint oscillation in advance, we also employ a feedforward controller to operate the actuator. Moreover, the actuator can be regarded as the robotic "muscle-tendon" for its function is similar to the muscle-tendon model in human body. Therefore, we apply this actuation to a virtual robot arm based on the Musculoskeletal Robot System (MRS) to evaluate the performances of elastic actuators. The results of experiments indicate that this actuation is effective and contributed to realize the compliant locomotion.