Coordination Control for Parallel Actuation of Hydraulic Power Assisted Ball Screw Drive System
Hydraulic actuators are commonly incorporated into the vertical feed drive system of heavy duty machine tools to achieve higher load capacity and stiffness by balancing the moving load.In the linear motion control system with ball screw and cylinder driving in parallel,interactions between two drive sets are directly related with machining accuracy.On one hand,motion synchronization should be dealt with in term of master and slave scheme with hydraulic cylinder following the speed generated by screw nut real-timely.On the other hand,temperature rise due to heat generation of moving parts causes not only thermal expansion of the screw shaft but also property change of hydraulic oil,finally exerting a significant influence on the positioning accuracy.In this paper,the coupled model of this combination is built up to analyze the dynamic performance under different operating conditions.Based on the electro- mechanical system model with hydraulic dynamics and thermal dynamics,the problem is formulated as coordinating the velocity of two actuation systems with coupling.The hydraulic actuator is modeled as a combination of an ideal velocity source and a spring for modeling the compressibility effects of the fluid medium to address the coordination control issue.It is shown in the simulation results that the proposed control strategy can achieve desired coordination of different drive systems with acceptable tracking errors.
passive control hydraulic actuator temperature rise positioning accurancy coordination
Hu Shi Jun Yang Xuesong Mei Guofang Gong
School of Mechanical Engineering Xian Jiaotong University Xian, China;State Key Laboratory of Flui School of Mechanical Engineering Xian Jiaotong University Xian, China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou, China
国际会议
重庆
英文
1010-1014
2015-12-19（万方平台首次上网日期，不代表论文的发表时间）