Analysis Of Jumping Mechanics And Trajectory Optimization For Frog Inspired Robots

Mobile robot has been widely used in the production of human society nowadays.Comparing with the wheeled robot,the jumping robot has advantages of high motion efficiency on the uneven ground due to its outstanding explosive force.However,comparing with the conventional robot,the dynamic control of the jumping robot is the main hindrance to prevail.In order to solve this problem,different jumping schemes are designed according to the different working requirements of robots.The optimal control strategy of high jump and long jump is obtained based on the optimization of robot trajectory by genetic algorithm.The jumping model of frog robot was established by mechanics analysis,which takes into account the main factors that affect the jump performance.In this dissertation,the frog is chosen as the model of the jumping robot from the field of bionics because of the excellent jumping ability and movement structure.In this model,the structure of the frog is considered as a planar linkage and a theoretical analysis is conducted based on this consideration.The kinematic model of each joint is established by analyzing the relationship between the motion trajectory of each joint,the center-of-gravity velocity,and the joint torque during the jump.According to the requirement of crossing different obstructions,two sets of jumping schemes are designed.By comparing the jump performance of robots under different take-off times based on genetic algorithm,the optimal control strategy for each joint under different jump exponents is obtained.The correctness and feasibility of the program are verified by Matlab simulation and the existing experimental data.The mechanical analysis systems in this dissertation simplify the complex calculations of kinematics and dynamics,and the method can be extended to the study of robot motion applied to arbitrary spatial force system.The important control factors that influence the jump performance of robots are obtained by optimizing the trajectory of six joints of the robot.The inverse kinetic equation can be used to solve the problem of strong coupling and nonlinearity between theequivalent torques of each joint.Because of the higher and farther jump distances,the frog robot can be utilized to work under various practical circumferences.