摘要
对平面3自由度并联机器人进行了运动学建模和运动控制研究。在平台运动过程中,对柔性杆上压电陶瓷的振动进行实时采样,获取振动信号的情形和主要模态。在高速运动到目标点时,由于柔性杆弹性变形过大导致存储能量过高,使得残余振动可能转化为自激振动。由于平台存在建模误差,摩擦,间隙,机电耦合等非线性因素,无末端传感器,采用非线性算法半闭环反馈控制。在特定的区域,通过获取伺服电机编码器位置值并与所需脉冲值进行比较,应用非线性PD算法进行同向补偿实验,控制伺服电机的摆动,从而有效地抑制住了平台自激振动。
The kinematic model of a planar three degree of freedom flexible parallel robot was established,and its kinematic control was carried out. During the motion of the platform,the real-time vibration signals were sampled by using PZT sensors bonded on flexible links. to understand the vibration status of the flexible links and the main mode shapes of the platform. When a flexible link reaching the target point at a high speed,its residual vibration may convert into selfexcited vibration due to the energy stored in the elastic deformation of the flexible link. On account of the nonlinear factors,such as modeling error,friction,clearance and electromechanical coupling,a nonlinear algorithm and a semi-loop feedback control were adopted in case no sensor was fixed on the end. In certain regions,by obtaining the value of the servo motor＇s encoder and comparing it with the desired count of pulses,the nonlinear PD algorithm implemented a same direction compensation experiment,so that the oscillation of the servo motor was controlled to suppress the self-excited vibration rapidly.
出处
《振动与冲击》
EI
CSCD
北大核心
2017年第21期138-143,共6页
Journal of Vibration and Shock
基金
国家自然科学基金(U1501247
91223201)
广东省自然基金(S2013030013355)
关键词
柔性并联机器人
运动控制
自激振动
主动控制
planar flexible parallel robot
kinematic control
self-excited vibration
active control
