二自由度七连杆机器人腿部机构优化设计

Optimum design of two degree freedom seven-bar robot leg mechanism

文章推导了二自由度七连杆机构运动分析计算公式,建立了七连杆机器人腿部机构优化设计的数学模型。以长半轴100 mm、短半轴40 mm的椭圆曲线作为机器人足端的相对理想轨迹曲线,采用遗传算法对七连杆机器人腿部机构进行了优化设计。优化的七连杆机器人腿部机构足端的实际轨迹曲线几乎与理想轨迹曲线重合,足端点的最大、最小x坐标分别为100.035,-100.036 mm,最大、最小y坐标分别为40.005,-40.009 mm,与理想轨迹的椭圆长轴、短轴半径的最大相对误差仅为0.036%。利用优化的七连杆机器人腿部机构,设计了6足仿真机器人,并采用UG软件对优化的七连杆机器人腿部机构和6足仿真机器人进行了运动仿真,运动仿真结果非常理想。

In this paper,motion formulae of two degree freedom seven-bar mechanism are derived a mathematical model is established for optimal design of the seven-bar leg mechanism of mobile robot.The elliptic trajectory curve with the long half axis of 100 mm and the short half axis of 40 mm is selected as the relative ideal trajectory curve of robot foot endpoint.The two degree freedom seven-bar robot leg mechanism is optimized by using the genetic algorithm.The foot endpoint actual trajectory curve of the optimized seven-bar leg mechanism of robot almost coincides with the ideal elliptic trajectory curve.The maximum and minimum x coordinates of the foot endpoint are respectively 100.035 mm and-100.036 mm,and the maximum and minimum y coordinates are respectively 40.005 mm and-40.009 mm.The maximum relative error with the long axis and short axis radius of the ideal ellipse trajectory is only 0.036%.Applying the optimized two degree freedom seven-bar robot leg mechanism,the hexapod simulation robot is designed.The motion simulation of the optimized seven-bar robot leg mechanism and the hexapod simulation robot are carried out by UG software,and the simulation result are satisfactory.