Papers by Author: Hao Wang

Abstract: Ultra-precision raster milling is one of the most significant techniques for the fabrication of high precision components with the surface roughness less than 10nm and form errors less than 0.2 um, without the need for any subsequent polishing. However, no matter how well a machine may be designed, there is a limit to the accuracy that can be achieved. This paper studies the machining errors caused by the diamond tool and the axis motions using Freeform 705G. With an empirical approach, the error sources are separated based on their effects on the surface finish. The main source leading to poor surface finish is identified. This establishes a basis for subsequent error compensation and equipment maintenance.

Abstract: Nowadays faceted reflector design has become popular in automotive illumination systems. The advantage of a compound surface enables it to achieve the required hot spot intensity by directing more than 60% of the generated light towards the road, thereby largely illuminate the area through the aperture. The research is oriented to fabricating the mold insert on ultra-precision raster milling (Freeform 705G). In this paper, the tool path generation method for automotive headlamp reflectors is studied, and a practical gouging detection and avoidance algorithm is proposed. The surface roughness and form accuracy (peak-to-valley height) are then calculated theoretically using mathematical formulae. Through the tool path generation of a small but representative surface patch with a gap, a possible way is finally found to generate the tool path for such a class of freeform surface with special equipment.