幅相控制策略在六自由度运动模拟器中的应用

Application of the amplitude-phase control strategy in a 6-DOF motion simulator

由于六自由度运动模拟器自身的闭环频率特性及非线性等因素,对于正弦输入信号存在幅值衰减和相位滞后,很难实现对高频正弦信号的精确跟踪,针对这一问题采用基于Widrow-Hoff学习算法的幅相控制策略.利用运动学正解间接得到的运动模拟器上平台位姿的反馈信号,通过该控制策略迅速地调整系统输入正弦信号的幅值和相位,使系统输出在短时间内对设定信号进行精确跟踪.仿真和实验表明,该方法在实现六自由度运动模拟器对正弦信号的精确跟踪问题上明显优于常规的经典控制,对于其他正弦运动的精确跟踪系统同样具有普遍意义.

Due to closed-loop amplitude and frequency response characteristics and nonlinear factors in 6-DOF motion simulators, it＇s difficult to accurately track high frequency harmonic motion. To solve the problem, this paper proposes a control strategy based on the Widrow-Hoff learning algorithm. It adopts the feedback signals of position and orientation of the moving platform, which is indirectly achieved by solving the forward kinematics of the 6-DOF motion simulator, to quickly adjust the amplitude and phase of the input harmonic motion signals. Thus, it can en- able the output signal to accurately track the input signal in a short period of time. Simulations and experiments prove that the control strategy is obviously superior to the conventional control strategy in tracking harmonic motion of 6-DOF motion simulators. It also has universal significance to other systems that must precisely track harmonic motion.