注塑机注射速度的离散预期学习控制  

DISCRETE ANTICIPATORY LEARNING CONTROL OF RAM VELOCITY IN INJECTION MOLDING MACHINES

作　　者：崔彩莲[1] 孙明轩[1] 

机构地区：[1]浙江工业大学信息工程学院,杭州310014

出　　处：《机械工程学报》2007年第6期41-47,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(60474005)。

摘　　要：针对注塑成形过程的重复运行特性,采用离散预期学习控制方法对注射阶段的关键变量注射速度进行控制。针对离散化后的注塑机注射速度模型,根据收敛性条件以两步法设计预期学习控制中的两个参数——超前步长与学习增益,并与连续预期学习控制作了比较。当收敛性条件不能在整个频段内满足时,利用DFT/IDFT截断可学习频段外的频率信号,保证跟踪误差单调收敛,并在离散频域内讨论测量噪声存在及初始定位不可重置时学习算法的跟踪性能。仿真结果表明,对于给定的期望注射速度曲线,该方法能得到比P型、D型迭代学习控制(ILC)更满意的跟踪性能,且具干扰抑制能力。A discrete frequency domain design is presented for anticipatory learning control, and applied to ram velocity profile tracking in injection molding process by virtue of the repetitive nature. Two adjustable parameters, the lead-time and the learning gain, are designed in two steps, in contrast with the continuous counterpart. The monotonic decay of the tracking error is guaranteed by cutting off the frequencies beyond the learnable band with the aids of DFT/IDFT. The tracking performance is theoretically examined in the presence of initial resetting errors and measurement noise. Numerical simulation is conducted to demonstrate the effectiveness of the proposed anticipatory learning control, with the comparison of both P-type and D-type ones.

关 键 词：预期学习控制 注塑机 注射速度 离散时间 频域 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]