Research On Structure And Dynamics Of Jumping Four-legged Bionic Robot

The research of special robots is a hot issue in the field of intelligent research.In recent years,the four-legged robot as one of special robots,more and more research about it has been carried out by related institutions at home and abroad.Quadruped robots are mainly used for transportation or detection,its sports performance as one of its performance standards is constantly improving.The traditional theoretical research on Walk,Trot and other gaits is more mature.The research on the performance of the jumping gait has gradually become a research hotspot.If the quadruped robot has the ability to jump,it will enable it to have more athletic performance.The combination of multiple sports gait enables the quadruped robot to cope with special complex terrain environments such as mountain search and rescue,cave exploration activities.In this paper,a novel bionic quadruped robot with jump as the main motion gait is designed with the hare as the bionic object,and relevant theoretical research is carried out.This paper analyzes the skeleton structure of jumping mammals and the jumping characteristics in jumping motion.Based on this,the degree of freedom,topology and basic structural parameters of the overall structure are determined.By analyzing several common driving forms,the driving method suitable for jumping motion is determined,and the relationship between the hydraulic cylinder lever extension and joint variables in hydraulic drive is analyzed.Based on the designed mechanical structure,it is simplified to a multi-link structure.The relationship between the end motion trajectory of the jumping quadruped robot and the joint variable is established by D-H coordinate transformation method,and the forward and inverse kinematics of the landing phase are derived,and the forward and inverse kinematics of the prancing phase are derived.Planning the trajectory of the entire jump phase includes:take-off phase,prancing phase,and landing phase.The trajectories of the whole hopping stage are planned:the take-off phase,the prancing phase and the landing phase,and the corresponding changes of the joint rotation angle with time are solved by kinematics simulation.The Lagrange equation is used to analyze the dynamics of the prancing phase,and the ground mechanics of the jumping quadruped robot is analyzed.By analyzing the force of the quadruped robot in the landing stage,and deducing the force of the foot end between each leg structure,the joint driving torque is solved.Through the inverse dynamics simulation calculation of ADAMS simulation software,the variation law of the contact change between the foot end and the ground during the jump process is analyzed,and the force analysis in the jump process is combined to verify the feasibility of the plan.Based on the bionic object,this paper establishes a virtual prototype model of the jumping quadruped robot,and performs kinematics analysis and dynamic analysis on the leg structure.The kinematics simulation and dynamics simulation are used to plan and design the jumping motion.The research provides a reference for the research of subsequent control systems.