数控蒙皮拉形试验系统及精度分析

为研究飞机蒙皮零件在拉形过程中的变形行为,在自行研制的多用途三轴加载试验机的基础上,采用数字PID控制算法,对试验系统的控制软件进行了改进,实现了加载油缸的速度控制以及同轴两油缸的位移同步控制,建立了数控蒙皮拉形试验系统.试验结果表明,系统具有较高的精度,符合大多数常见蒙皮零件进行试验的要求,为进一步研究蒙皮成形过程提供了良好的试验环境. 

Development on numerical control testing system for skin stretch-forming and analysis of accuracy

To study the deformation behavior of aircraft skin parts during the process of stretch forming, numerical control testing system was established on the basis of universal three axes loading machine by analyzing the characteristic of skin stretch forming technique. Velocity control of hydraulic cylinders and displacement synchronous control of same axial hydraulic cylinders were realized by introducing the improved digital proportional, differential, intergral (PID) control algorithm and the system is competent for most of stretch forming test. Testing result shows that the control precision of testing system is well and the performance is reliable, it provides the experimental basis for the further research.