Research On Key Technology Of Slow Tool Servo

Optical freeform surface is a kind of special complex surface with irregular shape.Its application in optical systems can improve performance,reduce costs and system size,thereby obtaining high-quality images.In recent years,optical freeform surfaces have been increasingly used in many fields such as optics,medicine,fiber optic communications,and life sciences.By using a very compact design such as free-form surface,a smaller space envelope can be achieved,the weight of the optical system is lighter,the number of optical surfaces in the optical system can be reduced,and the collective aberration can be reduced.Through balance and control,the optical performance of the system is better improved,that making it more and more widely used in defense,aerospace,electronic instruments and other fields.However,the requirements for its surface accuracy and surface roughness are high,and it needs to reach the micron or even submicron level.Therefore,the ultra-precision machining of optical freeform surfaces become more and more important.As a kind of ultra-precision numerical control manufacturing technology,the slow-knife servo turning technology has laid a reliable technical foundation for the mechanical processing of the optical surface of free-form surface devices and is currently a hot research topic in the world.This article focuses on slow-servo turning technology,and the main contents include:(1)This paper studies the problem of trajectory planning in the process of slow tool servo turning,analyzed the principle of slow tool servo turning,and analyzed the two commonly used trajectory layout methods.An evaluation method based on a preprocessing matrix is proposed to reduce the amount of calculations required during the calculation process,simplify the calculation process,and perform simulation analysis from the aspects of sparse interpolation points and bow height errors.(2)Studied the acceleration and deceleration planning in the process of slow tool servo turning.Analyzed the advantages and disadvantages of the T-curve acceleration and deceleration control and S-curve acceleration and deceleration control methods.Aiming at the problem that sudden changes in acceleration curve and acceleration curve can cause machine tool shock,this paper proposes a five-segment S-curve cosine acceleration and deceleration control method,which can effectively reduce the impact of machine tool.(3)Carry out the experiment of slow tool servo turning,design and process the surface of sine grid and micro lens array.The processed workpieces are inspected to obtain the two-dimensional and three-dimensional topography of the workpiece surface,and compared with the design values to verify the effectiveness of the proposed algorithm.