集成式数字阀控气缸位置伺服控制研究

Research on Integrated Digital Valve Controlled Cylinder Position Servo Control

气缸在任意中间位置定位的控制是既有广泛实际需求,又有很大技术难度的一个难题。采用气动伺服阀、高速开关阀等控制方式虽然可以实现较高精度的气缸定位,但伴随而来的是成本显著增加或运行速率的降低。为此,研究采用一种集成式数字阀用于气缸的位置控制,以期在低成本的前提下,能高速率地实现较高精度的气缸位置控制。首先通过理论分析和数值仿真设计了一种结构紧凑的集成式数字阀,该阀可以高效地控制输出流量,进而在高速大流量和低速小流量的控制需求上切换。在此基础上,研究了基于这种集成式数字阀的位置控制策略。试验结果表明:采用PID+模糊混合控制策略时,系统在目标点附近保持稳定,重复定位精度可达0.3 mm,响应时间小于1.2 s,具有良好的应用前景。

The positioning control of cylinder in any intermediate position is a problem with wide practical demand and great technical difficulty.The use of pneumatic servo valves or high speed on-off valves control methods can achieve a higher accuracy of cylinder positioning,but accompanied by a significant increase in costs or a reduction in operating speed.Therefore,an integrated digital valve was used for cylinder position control in order to achieve high precision cylinder position control at a high speed under the premise of low cost.A compact digital valve was designed through theoretical analysis and numerical simulation.The valve could be used to efficiently control the output flow,then switched on the control demand of high-speed large flow and low-speed small flow.On this basis,the position control strategy based on the integrated digital valve was studied.The experimental results show that the system remains stable near the target point when the PID+fuzzy hybrid control strategy is adopted.The repeatability of positioning accuracy is 0.3 mm and the response time is less than 1.2 s.It has good application prospects.