Structural Parameter Optimization And Control System Design Of A Hexapod Robot

Moving on the unstructured terrain in nature, commonly used vehicles suchas vehicles with wheels or tracks often fail to function well. The contact typebetween the end of the hexapod robot’s feet and the ground surface is point tosurface, so that it can adapt to the unstructured terrain well. It is widely used inextreme environment such as rescue after disaster, nuclear industry detection, etc.In order to improve the adaptability of the robot to the rugged terrain, we oftenincrease its active degrees of freedom. However, too many redundant driversmake the robot control system extremely complex. In this paper, the degree offreedom has not been increased, and by optimizing the parameters of the robotstructure, the adaptability of the robot to the rugged terrain has been improved.First of all, the swinging leg has been simplified as a serial-joint robot armwith3DOF, the supporting leg has been simplified as a parallel robot with threechains. Based on the D-H parameters and Jacobian matrix, forward and inversekinematic analysis of supporting and swinging leg has been done.Secondly, by define several different optimization objective functions, theparameters of robot leg body structure have been analyzed via simulationsoftware ADAMS. Then a group of reasonable structure parameters could beenobtained. Based on kinematic analysis, feet trajectory has been designed by usingthe polynomial fitting method, and it has been verified via ADAMS.Thirdly, a control system based on ARM has been designed for our hexapodrobot. It is a multi-channel digital servo control system which can control therobot’s18active driver joints, infrared distance sensor easily.Finally, experiments have been executed on our robot prototype. Thedesigned control system and feet trajectory have been testified working well.