Structural design of a frog-like hopping robot with consideration of vibration and its kinematic analysis

A natural frog was taken as the research target to develop a frog-like hopping robot. Based on the analysis of the physiological structure and jumping abilities of a frog, a frog-like hopping robot with five joints including a fore leg and a hind leg was developed. To reduce the shock and vibration influence generated during the take-off and the landing phase of the robot, flexible transmission combined with spring and synchronous belt transmission is adopted. The robot model is simplified as a parallel mechanism with seven links for the state when the robot legs touch the ground. Based on the simplified model, its forward and inverse kinematics are analyzed. The robot Jacobian matrix for the state is calculated by the method of solving branched chains Jacobian matrixes.