Abstract: In the evaluating process of hole group composite position error, the traditional numerical optimization methods are generally difficult to find an ideal location for the geometric frame to meet the minimum condition criterion, especially when the position tolerance follows the principle of MMC and the measured features still do not reach the minimum material size, parts judged unqualified may also be repaired. Aiming at solving the above-mentioned problems, the adaptive genetic algorithm is proposed to search the best location for geometric frame globally, and at the same time, the error compensation due to following MMC principle is taken into account while searching. In addition, the repair-ability judgment and correction calculation are also carried out against failed parts, which will further reduce the false rejection.

Key words: mechanical design, error evaluation, genetic algorithm, composite position, hole group