运动助力机械臂轨迹跟踪误差校正方法

Trajectory Tracking Error Correction Method of Motion Assisted Manipulator

运动助力机械臂的轨迹跟踪控制是实现高精度工作的关键。由于运动助力机械臂参数存在的不确定性等因素,导致运动助力机械臂轨迹跟踪误差较高,为此,提出了运动助力机械臂轨迹跟踪误差校正方法。分析运动助力机械臂空间位置和变换关系,根据运动助力机械臂关节与连杆之间的空间坐标矩阵变换过程,构建齐次坐标变换矩阵,获取机械臂末端执行器的空间位姿矩阵。通过定义机械臂轨迹的相关性特征集,得到机械臂轨迹跟踪误差的校正指标。基于置信概率计算,确定机械臂轨迹跟踪误差校正的约束范围,构建约束参量分析模型。采用遗传算法的原理,求解运动助力机械臂轨迹跟踪误差校正参数,实现运动助力机械臂轨迹跟踪误差校正。实验结果表明,所提方法的运动助力机械臂轨迹跟踪误差校正效果较好,能够有效提高运动助力机械臂轨迹跟踪误差校正精度。

The trajectory tracking control of motion assisted manipulator is the key to achieve high-precision work.Due to the uncertainty of the parameters of the motion assisted manipulator,the trajectory tracking error of the motion assisted manipulator is high.Therefore,a trajectory tracking error correction method of the motion assisted manipulator is proposed.The spatial position and transformation relationship of the motion assisted manipulator are analyzed.According to the transformation process of the spatial coordinate matrix between the joints and links of the motion assisted manipulator,the homogeneous coordinate transformation matrix is constructed to obtain the spatial pose matrix of the end effector of the manipulator.By defining the correlation feature set of manipulator trajectory,the correction index of manipulator trajectory tracking error is obtained.Based on the calculation of confidence probability,the constraint range of trajectory tracking error correction of manipulator is determined,and the constraint parameter analysis model is constructed.Based on the principle of genetic algorithm,the trajectory tracking error correction parameters of motion assisted manipulator are solved to realize the trajectory tracking error correction of motion assisted manipulator.The experimental results show that the trajectory tracking error correction effect of the proposed method is good,and can effectively improve the trajectory tracking error correction accuracy of the motion assisted manipulator.