Abstract: It is very important for the quality evaluation of shaft and hole parts to evaluate the roundness error accurately. Aiming at the problems of principle error or model error in the commonly used roundness error evaluation methods, a roundness error evaluation method which fully meets the definition of the minimum zone method is proposed. This method is an evaluation method that combines the area searching algorithm with the geometrical structure evaluated by the minimum zone method of roundness error. The quasi-central center are determined by the area searching algorithm. Then it is judged and adjusted according to the quasi-central center and geometrical structure. Finally, it can accurately find the center of the minimum zone circle. So the exact roundness error of the minimum zone method can be obtained. Several sets of simulation data are constructed. And the validity and correctness of this method are proved by comparing the evaluation results of this method with the preset values. After evaluating other literatures' data and comparing, the results further show that the evaluation results of this method are accurate, reliable, stable and efficient. It can effectively overcome the shortcomings of current roundness error evaluation methods.

Key words: roundness error, minimum zone, cross structure, area searching algorithm