Design And Research Of A Biped Robot Based On Multi Loop Coupling Parallel Mechanism

With the development and popularization of foot robots,the functional demand for bipedal robots is getting higher and higher,and the performance constraints brought by the traditional bipedal robots due to the structure of their mechanical legs in series make it gradually difficult to adapt to the multi-functional task requirements.The use of generalized parallel mechanism to design robot mechanical legs is an effective way to improve the performance of bipedal robot mechanical legs,in the generalized parallel mechanism multi-ring coupling parallel mechanism due to its high bearing capacity,motion output type controllability and other characteristics suitable as a mechanical leg configuration.In this paper,the multi-ring coupling parallel mechanism has been applied to the mechanical leg of the bipedal robot,and a high-load-bearing bipedal robot with the ability to control the ankle joint at the remote end has been designed to improve the slope adaptability and bearing capacity of the traditional bipedal robot.The configuration synthesis of multi-ring coupling parallel mechanisms that meet the motion needs has been carried out based on group theory,and bipedal robots have been designed based on the preferred mechanisms.Kinematic analysis and Jacobian matrix solution have been performed on multi-ring coupled parallel bipedal robots,and kinematic analysis and Jacobi matrix have been verified based on MATLAB and Adams.The solution analysis of the singular position,stiffness and dexterity of the mechanical leg based on the Jacobian matrix has been performed,and the results show that the multi-ring coupling parallel mechanical leg performs well.The gait space of bipedal machines has been solved based on kinematics,and the bearing capacity of the robot has been analyzed,which proves that the multi-ring coupling parallel robot improves the problem of insufficient bearing capacity of traditional tandem robots to a certain extent.The overall centroid trajectory of the bipedal robot when moving has been planned with the help of the ZMP criterion,the bipedal robot centroid has been controlled by the tail centroid to move in this trajectory,and then the foot trajectory of the swing leg has been planned based on five polynomials,and the end of the planned trajectory has no acceleration mutation,which meets the requirements of controlling the ground force of the mechanical leg,and finally the gait of each common working process has been planned to complete the gait planning of the bipedal robot.A three-dimensional model of the multi-ring coupled parallel bipedal robot prototype has been established,and then the motion of the prototype has been simulated and analyzed based on Adams,and the robot driving force curve in the pre-progressive state has been planned,which shows that the mechanical leg has relatively good dynamic performance.A prototype has been built and functional verification experiments have been carried out to further verify the performance of the multi-ring coupled parallel bipedal robot,using the steering gear as the driver of the robot,and the control system of the steering gear and the physical prototype of the robot have been built.Then,the slope adaptability experiment and bearing capacity verification have been carried out,and the results show that the designed multi-ring coupled parallel bipedal robot has ankle control ability,which can meet the slope adaptability of the robot and have good bearing performance.The research in this paper demonstrates the feasibility of applying a multi-ring coupling parallel mechanism to a mechanical leg to improve the performance of traditional mechanical legs.