Research On Driving Control System Of Simulated Three Dimensional Motion Platform Based On Linear Ultrasonic Motor

The source of this topic is a key project of national natural science foundation of GuangdongJoint Fund named “Study on the key theory and technique of precision electronics manufacturingequipment”(the number of Fund is U0934004)on2009.In order to improve the capacity of advanced manufacturing technology and equipment in China,accelerate the industrialization process and short the gap between developed countries and China, ithas great practical significance to develop a new piezoelectric micro-motion platform system of highpositioning accuracy and large travel with independent intellectual property rights.The principle of linear ultrasonic motors (USM) is made the micro-deformation of piezoelectricmaterials into a micro-amplitude ultrasonic vibration of elastic body by the inverse piezoelectric effectof piezoelectric ceramic materials. It can promote the load to do a linear motion directly by thefriction between the stator and the promoter. Because of its no motion conversion mechanism, simpleStructure, quick response, self-locking when power off and high resolution, the USM can be analternative to traditional electromagnetic motors as a drive unit in motion platform.Firstly, a simulated three-dimensional motion platform based on linear ultrasonic motor and itsdriving control system is designed. The V-shape ultrasonic motor with double amplifier poles is usedas a drive unit. The platform is made of three one-dimensional motion platforms. The driving controlsystem controls the position and speed of linear ultrasonic motors precisely and keeps the platformmoving in three directions.Secondly, the driving control system is made of a floating-point DSP core chips TMS320F28335of TI, a CPLD chip, controllers of ultrasonic motor and so on. It’s a closed loop control system by theposition feedback signal of optical encoder. It can control the precision and speed of the motionplatform with PC. It has good flexibility and portability by driving the system integrated into a box.Thirdly, do the algorithm research of motion platform on the grounds of hardware. Test itsposition resolution and research the ways of improving platform positioning accuracy by PID andmicro-step control. By using a linear encoder which resolution is0.5μm/count, the system effectivelycontrols the motion platform move in three directions of x, y and z. It’s position resolution is100nmand accuracy is1μm. The platform can be used as micro-manipulator for biomedical engineering.