摘要
以八轴独立转向的工程车辆为原型研究了提高轮廓精度的交叉耦合控制策略,对多轴转向系统和转向过程中的一致性耦合误差进行了运动学分析。基于电液伺服转向机构的工作原理,建立了单个转向机构的动力学模型。为了增强系统的鲁棒性,减小多轮系轴间的一致性耦合误差,在单轴采用滑模控制器进行位置跟踪的同时,引入了基于比例积分(PI)的交叉耦合控制器,对轴间一致性耦合误差进行补偿,实现了以位置跟踪和轮廓精度为目标的交叉耦合控制。以纵行转向为例仿真验证了控制算法的有效性。
Taking a construction vehicle which is independent driven by 8-axis steering system as the study prototype,the cross-coupling control strategy is discussed to improve the contour accuracy.The kinematic analysis of multi-axis steering system and consistent coupling error is introduced.According to the working principle of electro-hydraulic servo mechanism,the mathematical model of single steering mechanism is established.In order to reduce the coupling error caused by different load disturbance between the different steering axes,the sliding mode control for the position tracking of the single-axis is designed.Meanwhile,a crossing-coupling controller based on PI algorithm is proposed to compensate the consistent coupling error.Thus,position tracking and contour accuracy of multi-axis steering system is achieved.Taking the longitudinal steering system for example,the simulation results prove the effectiveness of the control algorithm.
基金
高等学校博士学科点专项科研基金(20080061061)
关键词
工程车辆
转向系统
滑模控制
交叉耦合控制
construction vehicles
steering system
sliding mode control
cross-coupling control
