Design and control of a pneumatic musculoskeletal biped robot

Abstract

Abstract. BACKGROUND: Pneumatic artificial muscles are quite promising actuators for humanoid robots owing to their similar characteristics with human muscles. Moreover, biologically inspired musculoskeletal systems are particularly important for humanoid robots to perform versatile dynamic tasks. OBJECTIVE: This study aims to develop a pneumatic musculoskeletal biped robot, and its controller, to realize human-like walking. METHODS: According to the simplified musculoskeletal structure of human lower limbs, each leg of the biped robot is driven by nine muscles, including three pairs of monoarticular muscles which are arranged in the flexor-extensor form, as well as three biarticular muscles which span two joints. To lower cost, high-speed on/off solenoid valves rather than proportional valves are used to control the muscles. The joint trajectory tracking controller based on PID control method is designed to achieve the desired motion. Considering the complex characteristics of pneumatic artificial muscles, the control model is obtained through parameter identification experiments. RESULTS: Preliminary experimental results demonstrate that the biped robot is able to walk with this control strategy. CONCLUSION: The proposed musculoskeletal structure and control strategy are effective for the biped robot to achieve human-like walking.

Position control of a bio-inspired semi-active joint with direct inverse hysteresis modeling and compensation

“…Thus, the control of the joint is facilitated due to the simple geometrical relationship between muscle contraction and joint angle. 30 The pneumatic artificial muscle is manufactured by Festo, with a working length of 180 mm and a diameter of 20 mm. The stiffness and initial tension of the spring are 1.47 N/mm and 19.61 N, respectively.…”

An adaptive neuro-fuzzy based on a fractional-order proportional integral derivative design for a two-legged robot with an improved swarm algorithm

“…In [3], the authors introduce a new concept for online gait adaptation to the leg robots capabilities. In [4], the authors proposed a suitable proportional integral derivative (PID) controller for the two-legged robot to achieve the required positions for the joints to achieve stable walk patterns. In [5], the authors present a fractional-order proportional derivative (FOPID) controller for a hexapod robot to achieve the best performance for different ground properties.…”