This study evaluates a positioning method using multiple hole-and-pin sets to improve assembly accuracy by decreasing "assembly shift" caused by clearance fits. While typical two hole-and-pin configurations are standard, they often introduce undesirable assembly shift due to necessary clearances. Although prior research has addressed translational assembly shift suppression, the impact of multiple sets on rotational assembly shift remains insufficiently characterized. To quantify these effects, Monte Carlo simulations were conducted, comparing configurations of n=2, 4, and 6 hole-and-pin sets arranged in a circular pattern. The simulation incorporated normal distributions for hole (∅2.3±0.1), pin (∅1.7 ± 0.1), and position tolerances (∅0.2). The results demonstrate that increasing the number of sets suppresses assembly shift. Compared to the baseline requirement of n=2, the mean assembly shift size decreased by 7.8% for n=4 and 13.2% for n=6.
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