The leg structure design and motion analysis of connecting rod wheel leg hybrid mobile robot

In order to improve the mobility and adaptability of mobile robots in complex environments, this paper proposes a kind of connecting rod four-legged composite robot leg structure. The leg mechanism adopts the design of series and parallel composite connecting rod. Each leg contains two degrees of freedom of hip joint and knee joint, and the joint motor is installed on the fuselage. The main body of the wheeled structure is the driving wheel, which is mounted on the shank. The dead point position is used to ensure the stability of the link structure during the wheel motion. The objective function of optimal design of leg mechanism is obtained by statics analysis, the parameters of leg linkage mechanism are optimized by multi-objective optimization genetic algorithm, and the motion space of foot end is solved. Through Adams on the design of wheel leg compound mobile robot Trot gait, Walk gait and wheel leg convert motion simulation, the simulation results show that the foot type sports center of mass on the direction of gravity changes in the distance is less than 4 mm, in the process of movement joint torque biggest not more than 1.75 N ꞏ m, and a physical prototype was made for experimental verification. The simulation results and experimental results show that the designed linkage type compound leg structure can realize the basic stable movement of the foot and the stable switching function of the wheel foot.