Research On The Design Method Of Bio-inspired Legged Robot Based On The Tensegrity Structure

To improve the structural adaptability and simplify the control system of the traditional bio-inspired legged robot,a bio-inspired legged robot based on the tensegrity structure was designed by taking the biological structure of human leg as inspiration and combining the similarity between the tensegrity structure and human musculoskeletal system in terms of rigid-flexible coupling.The main contents of this paper include:First,the musculoskeletal system was extracted and simplified from the attachment position and geometric behavior of the muscle tissue on the bone,which based on the biological structure and movement mechanism of human leg.Thus,the equivalent model of Snelson X-shaped tensegrity structure of the same coupling relationship with leg was established.Second,in order to analyze the structural stability,the mathematical model of the basic unit of the legged robot was established according to the equivalent mapping model,and the shape finding analysis was carried out through the connection matrix.The dimensional parameters of the mechanism were determined by the dimensional parameters of the human legs.The motion characteristics of the mechanism unit were determined to obtain the workspace of the specified reference point.The stiffness matching method of tensegrity structure is given.Sequentially,The theoretical analysis of kinematics was completed.Then,the moving center of rotation of the bio-inspired knee joint was realized by the separation of rotation and translation movement,and the knee joint locking was realized by using the dead point of planar four-bar mechanism when the legged robot is standing.The crank slider mechanism and the displacement amplification mechanism were designed,and the rope was used to connect the robot foot and bio-inspired knee joint to realize linkage unlocking,so as to realize rigid-flexible transformation of the bio-inspired knee joint.And last,the physical prototype was manufactured and assembled according to the 3D model of the bio-inspired legged robot,and the validity and practicability of the proposed structure was verified through the physical prototype test of the robot hip joint driven by a single motor.