A Novel Wheel-legged Hexapod Robot With Strong Obstacle-crossing Ability

Traditional mobile robots are mainly divided into wheeled robots and legged robots.Wheeled robots have fast moving speeds and its speeds are stable and adjustable,but the terrain adaptability is poor and the crossing-obstacle ability is weak.The legged robots are good at crossing obstacles because of more degrees of freedom for control,but the control is complex and the movement speed is too slow.Combining the advantages of the two types mentioned above,this paper designs a new type of multipurpose wheel-legged Hexapod robot with strong obstacle-crossing ability.Firstly,the wheel-leg model was established and we analyzed the factors affecting the performance of the wheel-legs through ANSYS.Then the wheel-leg obstacle-crossing model was established to calculate the relationship between the obstacle-crossing ability and the number of spokes on the single axle.A single spoke wheel leg mechanism which is made by 3D printing was finally determined.Based on the obstacle-crossing way of the wheel-leg and combined with the characteristics of insects moving stably in nature,the body of the robot whose middle is wider than head and tail is designed.We choose tripod gait to control the robot.The design we proposed was verified in the form of simulation from ADAMS.The robot control system was developed on the principle of safety,high efficiency and simplicity.The communication between the upper computer and robot is used to monitor the running state of the robot.The control precision of the robot is improved by feedback control.Finally the experimental results show that the wheel-legged hexapod robot designed in this paper can realize the basic functions such as going forward and turning in different environment.We tested the robot's maximum obstacle-crossing height,jumping ability and continuous obstacle-crossing ability through self-made obstacles such as stairs.At last we tested the ultimate load of the robot by changing the control program.