关键词: 刀位, 活动标架, 火箭喷管, 曲面再设计

Abstract: The machining accuracy of large complex surface workpiece with low rigidity is very difficult to achieve. A typical characteristic should be considered in surface machining. The finishing surface model is unknown, and the random structural deformation is much larger than the design tolerance of target surface. A forward modeling technique for target surface redesign is developed based on E.Carten moving frame theory. And a computing method for cutter location points is then researched utilizing the measured data of reference profile and geometrical parameters. The spatial positions and orientations of measurable reference surface, datum surface and target surface are initially analyzed. On the base of the analysis, the finishing target surface is redesigned by using digital techniques in accordance with physical or geometric constrains. The cutter location points can be recalculated using the redesigned surface. An experiment of a liquid rocket nozzle with varying thickness was implemented. It is shown that the proposed method can satisfy the machining requirements of those workpieces with high performance and high geometrical accuracy.

Key words: Cutter location, Moving frame, Rocket nozzle, Surface redesign