Papers by Author: Jian Hua Lin

Abstract: This paper focus on the relationship between PA and the distribution of polishing pressure, on the basis of the theory that the distribution of polishing pressure is a Modified Gaussian Function and has highly symmetry. Through the simulation experiments, the optimum PA has been determined. And it’s further validated that this optimum PA fits for polishing large aspheric mirror under the conditions with both different internal pressure and bonnet decrement by a series of simulation experiment. It’s also found that PA makes little difference to the size of the contact area and the bonnet decrement has greater influence to the size of the contact area than the internal pressure.

Abstract: In order to turning the skirt of middle-convex and varying ellipse piston, this paper proposes a Variable Cross-section Helix Turning Trajectory (VCHTT) algorithm. it divide the turning trajectory of the piston skirt into transversal and helix, then obtain the coordinates of ellipse transversal cutter-contact points on the basis of centric polar radius arc interpolation (CPRAI) algorithm, and uses line surface intersection method to obtain the coordinates of helix cutter-contact points on the middle-convex and varying ellipse piston skirt. At last，merge two coordinates matrices to obtain the final coordinate surface of cutter-contact points of turning tool. With comparison, it finds that the VCHTT algorithm improves the interpolation accuracy by 0.04um than other methods.