Research on the global evaluation method of complex curve contour

With the development of the advanced precision manufacturing field, the curve profile is becoming more and more complex, and the profile curve evaluation is no longer limited to the two-dimensional plane. Aiming at the difficulty and low efficiency of complex contour evaluation of high-precision parts, this paper proposes a global evaluation method of three-dimensional curve contour. After the curve contour is extracted, dimensioned and calibrated, according to the definition of GB/T1182-2008 plane curve contour, an envelope circle equation is established to evaluate the contour of the complex line. The curve contour theoretical points are used to establish the envelope detection area function, and the position relationship of the measuring points relative to the theoretical contour is evaluated according to the circle function of the envelope group, and the line contour error is determined. Experiments show that the evaluation result is intuitive and can be traced back to the specific area of the curve contour. This method realizes the evaluation of the whole area of the spatially complex curve contour. The method is accurate and efficient, and has overall and unitary characteristics.