Numerical and experimental analysis of ball screw accuracy reliability with time delay expansion under non-constant operating conditions

A ball screw (BS) is a key functional component for precision machining equipment, medical instruments, and intelligent manufacturing production lines. The accuracy reliability of a ball screw plays a key role in the functioning of all such equipment. Since the operating conditions have time-dependent characteristics, the non-constant operating conditions affect the BS accuracy decay. In this paper, the numerical modeling and analysis of the BS accuracy decay are considered under non-constant operating conditions. The BS accuracy reliability under single and multiple non-constant operating conditions is investigated. The experimental findings on accuracy decay under non-constant operating conditions validate the proposed analysis. The average relative error of accuracy decay between the theoretical and the experimental findings is estimated at 10% (in the range of 10.15%-12.66%). The error is evaluated under the three different amplitudes operating conditions, including AL (non-constant axial load), FR (non-constant feed rate), and AL plus FR. The results show that the accuracy decay prediction model successfully predicts the BS accuracy reliability under non-constant operating conditions.