Research On The Disturbance Rejection Control System Of Smooth Elastic Floating Lapping

Diamond has some excellent performance in physics、chemistry mechanism. Diamond has been playing an important role in technology and industry. Especially, in the field of ultra-precision machining, diamond is considered the best ideal of ultra-precision cutting tool materials. with the technology and application development, People on the diamond surface made more stringent requirements. As the rigid material properties of diamond, Generally, Obtain a shape of the required accuracy and surface roughness of the difficulties of low diamond, Thereby, the precision diamond lapping technology, Have a good prospect and practical value.In processing of diamond lapping, there arc some factors which influence diamond lapping, like process condition, equipment and corresponding control system. But most important and base problem is improving lapped equipment control system, so how to improve move’s precision and stabilization of lapped machine is the key problem. This paper first discusses and analyzes the main factors of influence grinding device running accuracy and stability. The minitype and precise spindle system has been designed and done. It adopts fluid dynamic bearings technology and sensorless BLDC motor techcnology so that spindle system can rotates stably and precisely. Feeding system adopts the precision of servo motors into platform to radial feeding.We started from the diamond grinding mechanism to explore the nature of the reasons for the phenomenon of emergence of cleavage and micropore on the diamond surface:the phenomenon of cleavage and the micropore is due to the instable impact during the diamond lapping. We can see, from the diamond surface after elastic float lapping, that the variational impact is mainly produced by the end beating of grinding disc and the vibration of elastic beam. These interferes both vibration and impact different radial positions will make relative motion between the lapped diamond tools and grinding disc so that diamond tools cannot achieve the required processing precision and surface quality1". In order to restrain the vibration and impact caused for end jump to the diamond grinding surface quality in radial feeding process, this paper take use of the strategy by the adjustment of speed in the radial feeding process timely to control the impact on the surface of diamond.This paper proposes an idea of controlling radial feeding speed to regulate the impact from the end jump. With the characteristic of elastic floating grinding, pros and cons of commonly-used methods are analyzed and compared. After that it selects out the appropriate methods and works out the grinding control strategy offers in phases, meanwhile the overall program of grinding control system has been designed. On the basis of those, with the function desire of the control system, analyze, design and choose models of every part of the system. A close-loop simulation was made by putting the open-loop transfer function and the controller together. At last, the software of the control system has been programmed in LabVIEW environment, and impact control method verifying system is used to inspect the practicability of the system.