以实现仿人机器人步行稳定控制为目的,为克服零力矩点(ZMP)反馈控制算法不能补偿较大冲击干扰以及反射响应方法打断当前步行任务的缺点,以低成本微机电系统(MEMS)传感器及方向余弦矩阵描述的补偿算法构成航姿参考系统。提出了由姿态转角和角速度的线性组合表达的步行稳定性判据,并实现了躯干姿态校正的比例-微分控制器。基于仿人机器人全方位步态规划方法,调整下一步步幅和步频为行为方式,实现了步行稳定控制。样机实验结果表明:在原地踏步和稳定前进等情况下,机器人受到冲击干扰以致倾斜角度达20°时,仍能够不打断全方位步行且有效避免倾覆。
An attitude and heading reference system (AHRS) feedback system was established using micro-electro-mechanical system (MEMS) sensors with low cost and the compensation algorithm described by the direction cosine matrix to realize the stabilizing control of humanoids' walking, being aimed to overcome the defect of incapability to compensate the large disturbance when using the zero moment point (ZMP) feedback control algorithm and the shortcoming of the current walking task interruption when using the reflex response control method. The walking stability criterion expressed by the linear composition of posture angles and angular velocities was also proposed, with a proportion-derivative controller for torso pose adjusting also implemented. Walking stabilization control was realized by the action style of tuning the next stride and walking frequency using the omni-directional walking gait planning method. Experimental results with a physical robot show that the robot can effectively avoid omni-directional walking task interruption and fall over even if disturbed by an impulse to reach the maximum inclination of 20° when marching on the spot and walking forward steadily.
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