时变质量梁系统的振动主动控制研究

为了保证机械臂运动的高精度、准定位,采用主动控制技术降低结构的干扰振动是一项迫切而紧急的任务。该文以含变质量构件的弹性梁系统为对象,开展变质量弹性结构的振动特性研究和振动主动控制研究。使用模态叠加法推导了粘贴有压电片的变质量-柔性梁组合结构的控制方程,通过仿真获得变质量弹性梁系统的振动特性和运动规律。然后设计反馈控制器对质量增大系统和质量减小系统进行了振动主动控制,并采用时频分析技术分析了控制效果。仿真结果表明,变化的质量在引起系统振动频率改变的同时,还引起了一个附加的阻尼。在变质量时变系统的共振频率区间,通过反馈控制可有效抑制结构的振动。

Study on Active Vibration Control of Time-varying Mass Beam System

In order to ensure the high precision and accurate position of manipulators, it is necessary to suppress the undesired vibration based on the active vibration control technology. In this paper, taking the elastic beam system composed of the variable mass component as the subject of study, the vibration characteristics and the active vibration control of the variable mass elastic structure are studied. The governing equations of variable mass flexible beam composite structures with piezoelectric patches are derived by the modal superposition method. The vibration characteristics and the motion law of variable mass elastic beam system are obtained by simulation. A feedback controller is designed for the active vibration control of the mass increase system and the mass reduction system. The time frequency analysis technology is applied to analyze the control results. The simulation results show that the quality of the change causes an additional damping as well as the change of the vibration frequency of the system. The vibration of the structure can be effectively suppressed by the feedback control in the range of the resonant frequency of the variable mass time varying system.