一种改进的移动机器人运动控制算法

New kinematic control algorithm for mobile robots

在传统的控制系统中,控制器修正信号通常选取为跟踪误差的线性函数,虽然运算量较小,但在跟踪误差较大时,系统的响应速度较慢。为此,提出一种改进的运动算法,控制器修正信号选取跟踪误差的三次函数,并且为了克服在跟踪误差较大时高阶误差修正容易出现不稳定现象的问题,提出了修正信号增益分段线性化的方法。计算机仿真结果证明,在跟踪误差较小时该算法与传统算法具有相似的跟踪特性,但在较大跟踪误差时,该算法既提高了系统的响应速度,又保证了系统的稳定性。

A discrete state space model of the mobile robot is introduced and a modified kinematic control algorithm is proposed. In many traditional control systems, the correction signal of the controller is chosen as the linear function of the tracing error. Although less computation is needed, the response speed of the system is relatively slow. In the algorithm proposed, the correction signal is chosen as the cubic function of the tracing error. Furthermore, by a method of piecewise linearization of the correction gain, the instability that often occurs in a higher order system with larger tracking error is avoided. The performance of the control algorithm is investigated and analyzed by simulation. The results indicate that the new algorithm has similar tracing performance for small tracing error, but for large tracing error, the response speed of the system is improved while the stability is maintained.