针对无杆气缸和压电片驱动器同时实现柔性机械臂定位和振动抑制系统,采用模糊控制算法、变论域自适应模糊控制算法和间接自适应模糊控制三种算法进行试验研究。介绍系统构成以及气动和控制回路,给出系统模型。分析三种控制算法,给出变论域自适应模糊控制算法输出论域的自适应律,即通过在线调节模糊控制器的输入和输出变量的论域来改善传统控制器的性能;采用参数可调的间接自适应模糊控制器在线逼近理想控制器,推导其参数自适应律。考虑气缸长行程和气体压缩性、非线性等因素,引起控制滞后和容易激励柔性臂的高频模态振动,采用带阻滤波、低通滤波和时延补偿算法。进行气动驱动和压电驱动器抑制柔性机械臂振动和定位试验研究。试验结果表明,采用的三种控制算法都可以实现定位控制的同时,抑制柔性机械臂振动;自适应模糊控制算法优于传统模糊控制算法。
For simultaneous positioning and vibration suppression of a flexible manipulator system driven by a rodless cylinder and piezoelectric patches actuator, three control algorithms are adopted for experiments, including fuzzy control, variable universe adaptive fuzzy control and indirect adaptive fuzzy control. The system composition is introduced, as well as the pneumatic circuit and control circuit of the system. The system model is given. Three control algorithms are analyzed. Variable universe adaptive fuzzy control algorithm improves the performance of traditional fuzzy controller by adjusting the universes of input and output variables on line, and the adaptive law of output universes is developed. An indirect adaptive fuzzy controller with adjustable parameters is constructed to approximate the ideal controller, and then the parameter adaptive law of the fuzzy controller is deduced. Considering the cylinder's long stroke, gas compression and nonlinear pneumatic system factors, the hysteresis of control effect and the vibration of the flexible manipulator's high frequency modes will be caused. Band-stop filter, low pass filtering and time delay compensation algorithm are introduced into the control algorithm. Experiments on simultaneous positioning and vibration suppression of flexible manipulator are conducted. The experimental results demonstrate that the adopted three control algorithms can accomplish positioning and vibration suppress of the flexible manipulator simultaneously. The performances of the adaptive fuzzy control algorithms are better than the traditional fuzzy control algorithm.