Research Of The Emulation Of The Mechanical Loads For Industrial Computed Tomography

As a non-destructive testing technology, industrial CT (Computed Tomography)technology has been widely applied in the manufacturing. With the development of CTtechnology, more and more areas of industrial production take industrial CT toguarantee the online quality, which causes higher requirements to the speed and stabilityof each axis of industrial CT motion system. So, to analyze and emulate the loads ofindustrial CT are necessary and important for testing and improving the performance ofindustrial CT motion system. The purpose of this paper is to establish the mechanicalloads emulation system for industrial CT.Firstly, researches the typical scanning of industrial CT system, which involvesfour important motion modes. Then discuses the influence to motion performance casedby the inertial load, disturbance load, friction load, and belt drive load in detail. Themotor load emulation platform is designed in this paper. That is, two AC servo motorconnected to the coupling constitutes the implementing agencies of the loads emulationplatform; the PC, data acquisition card, and AC servo drive constitutes the controllersystem of the platform.A mechanical loads emulation algorithm based on the robust speed tracking isdesigned, which combine with the principle of loads emulation and the continuoussliding mode control used in the robust position tracking. Then discuss the software ofthe real-time control on PC in detail. The RTX real-time control subsystem provides anaccurate and reliable timer for the controller. Furthermore, the friendly interface isdesigned using LabWindows/CVI for the operator to set parameter and control theemulation platform.Finally, experimental results of the closed loop speed control of some linear andnon-linear loads are presented. Computer simulation (by Matlab/Simulink) results arealso provided for comparison purposes to show the performance of the load emulationalgorithm. The comparisons between experimental and simulated results have shownagreement. The emulation system can be used for the testing of robust and adaptivemotor drive control strategies, to improve the performance of motion system forindustrial CT.