直线定位平台扰动激励下柔性操作臂的耦合振动特性研究

Coupled vibration characteristics of flexible manipulators of a linear positioning platform under disturbance excitation

以直线定位平台柔性操作臂为对象,根据能量方法建立了系统的耦合动力学模型,考虑驱动过程中存在的运动波动,对直线定位平台的运动特性进行表征,结合建立的耦合动力学模型,得到柔性操作臂的耦合振动特性。通过理论分析和仿真实验,对不同运动特性下运动波动的扰动激励的作用机理进行研究。结果表明:运动波动对柔性操作臂的振动特性具有明显的影响,对于匀速运动情形,在起始阶段随着速度取值的增大,柔性操作臂的振动幅值有所增大,随着响应时间的增加,影响逐渐减小;对于匀加速运动情形,随着加速度取值的增大,柔性操作臂的振动幅值逐渐减小,且较大的加速度对波动的影响起到一定的抑制作用;理论与实验结果一致,验证了所建模型的正确性。研究结果对柔性操作臂的动态特性分析及振动控制具有一定的指导意义。

The flexible munipulator of a linear positioning platform was taken as a study object. Based on the energy method,the coupled dynamic model of the system was established. Considering motion fluctuations in its driving process,the motion features of the linear positioning platform were described. Subsequently,combining the established coupled dynamic model,the coupled vibration characteristics of the flexible manipulator were derived. The disturbance excitation action mechanisms of different motions＇ fluctuations were studied through theoretical analysis and simulations.The results indicated that the motion fluctuations have a significant effect on the vibration characteristics of the flexible manipulator; for the constant velocity motion situations,its vibration amplitudes increases with increase in the motion velocity in the initial stage,and with increase in the response time,the effect decreases; for the constant acceleration motion situations,its vibration amplitudes decreases with increase in the motion acceleration,larger accelerations have a certain suppressing action on the effect of the motion fluctuations; the results of theoretical analysis agree well with those of tests,the correctness of the established model here is verified. The study results provided a guidance for the dynamic analysis and vibration control of flexible manipulators.