Research On Thin Wall Rotation Profile Error Evaluation

Thin wall rotation is a key part of high-speed aircraft, it's manufacture precision results in the stability and the veracity of the high-speed aircraft directly. The measurement on profile shape and thick of the thin wall is an effective method for verifying the manufacture precision of the thin wall rotationThin wall rotation is complicated and thin-wall rotary part with three-dimensional free surface, its diameter in the cone bottom is about a third of its length, its measuring precision on geometric parameter is as high as micron-grade. The measuring instrument and measuring technique in being can not satisfy an accurate and fast measurement for the geometric parameter of the thin wall rotation. As a result, it is necessary to developing automatic geometric parameter measure equipment with high precision and high efficiency for thin wall rotation. This paper does research on thin wall rotation contour error evaluation, and so on.The reason of causing positional error is discussed in the paper. Then the present status and prospect of profile error evaluating technique and error correction technique of complex generatrix revolution accessory is summarized.A general geometric model and error evaluation model is introduced based on the saddle-point programming principles, the Frenet moving frames and the Cecaro methods. The profile error of revolution accessory is analyzed by the least-squares and the minimum zone evaluation methods. Revolution body has been fitted with cubic spline method.The software system is developed with VC++. It's composed by manual function, auto-measure function, auto-collection and auto-save function, automatic data processing function, error evaluation and visual output. The system with the character of running stably, friendly interface, high intellectualized degree, could meet the demands of thin wall ration geometric parameter measure. Furthermore, it's highly enhanced the flexibility and the automatization of thin wall rotation geometric parameter measurement.