基于模型预测控制的四足机器人斜坡自适应调整算法与实现

为了实现四足机器人在有斜坡地形下的自适应稳定行走,在模型预测控制基础上进行扩展,设计四足机器人在斜坡上的足端位置调整与躯干姿态自适应调整策略。由惯性测量单元(inertial measurement unit,IMU)测得机器人运动时的姿态参数,通过推导的足端轨迹算法,得到足端位置的坐标映射,调整机器人在斜坡上的重心位置;通过设计的“虚拟斜坡”躯干姿态调整算法,实现机器人在上坡过程中躯干姿态的自适应调整。利用实验室的四足机器人物理平台和搭建的实际斜坡地形环境,验证了所提算法的可行性和有效性。机器人平台验证结果表明,所提出的斜坡自适应控制方法提高了机器人在坡面上的稳定裕度,优化了足端运动空间,实现了四足机器人的自适应爬坡调整。

Algorithm of adaptive slope adjustment of quadruped robot based on model predictive control and its application

In order to realize the adaptive and stable walking of the quadruped robot on slope terrain, the adaptive adjustment strategies of both feet position and trunk posture of quadruped robot on slope were proposed based on the model predictive control. The posture determination parameters of the robot in locomotion were measured by the inertial measurement unit(IMU). By means of the derived foot end trajectory algorithm, the coordinate mapping of its toe position was obtained in order to adjust the center of gravity of the robot on the slope. Then the adaptive adjustment of the trunk posture of the robot in the process of climbing could be achieved through the trunk posture adjustment algorithm by means of designed “virtual slope”. With the help of the physical platform of quadruped robot and the actual slope terrain environment built in the laboratory, the feasibility and validity of the proposed algorithm are verified. Experimental result showed that the proposed slope adaptive control method had improved the stability margin of the robot on the slope and optimized the foot end motion space, thus leading to the realization of adaptive adjustment in climbing slope for the quadruped robot.