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Wu Shixiong
Wang Wen
Chen Zichen
Department of Mechanical Engineering, Zhejiang University,
Hangzhou 310027, China |
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ADAPTIVE MEASUREMENT METHOD BASED ON CHANGING-CURVATURE FOR
UNKNOWN FREE-FORM
SURFACE*
Abstract: Current measurement method for unknown free-form surface has low efficiency. To acquire given precision, a lot of null points are measured. Based on change surface curvature, a new measurement planning is put forward. Sample step is evaluated from the change curvature and the locally-bounded character of extrapolating curve. Two coefficients, maximum error coefficient and local camber coefficient, are used to optimize sampling step. The first coefficient is computed to avoid sampling-point exceeding the measurement range and the second control sampling precision. Compared with the other methods, the proposed planning method can reduce the number of the measuring-point efficiently for the given precision. Measuring point distributes adaptively by the change surface curvature. The method can be applied to improve measurement efficiency and accuracy.
Key words:
Free-form surface Adaptive sampling Curvature |