Research on Contact and Wear Characteristics of the Planetary Roller Screw Mechanism with Screw Misalignments

Abstract

Misalignments are unavoidable in most applications of the planetary roller screw mechanism (PRSM) due to many potential causes. However, the effect of screw misalignments on the contact characteristics for the PRSM have not been thoroughly investigated. In this paper, a comprehensive analytical procedure for the PRSM performance considering screw misalignments is proposed. First, the contact positions and clearances of the PRSM with screw misalignments are calculated. Next, an improved model is presented for evaluation of the load distribution, in which the variation of axial clearances is taken into consideration. The numerical results are validated by finite element analysis. Then, the precision loss model caused by wear is derived considering the variation of contact forces. The results indicate that the contact positions slightly change due to the misalignment angle of the screw, while the axial clearances and load distribution at the screw–roller interface are significantly affected. At the same time, the contact forces over thread vary periodically. In addition, the screw misalignment aggravates the wear of the PRSM, resulting in accuracy degradation. The theoretical investigations lay the foundation for the engineering application of the PRSM.

Review on errors and transmission characteristics of the planetary roller screw mechanism

“…In order to study the influence of eccentricity errors on the contact characteristics of PRSM, Meng et al 70 proposed a comprehensive analysis method considering screw misalignments. The results showed that screw eccentricity exacerbates wear of the PRSM, resulting in reduced transmission accuracy.…”

Performance and Challenges of Planetary Roller Screw Mechanism in Complex Conditions: A Comprehensive Review of Recent Progress

“…Meng et al [89] introduced a multiscale adhesive wear model considering thread surface roughness, providing insights into the wear characteristics and their impact on PRSM's performance. Meng et al [90] also explored the contact and wear characteristics under screw misalignments, indicating that misalignments significantly affect wear, potentially leading to accuracy degradation. Ma et al [91] and Xing et al [86] developed wear prediction models that underscore the importance of understanding the wear mechanisms for optimizing PRSM design and operation.…”

Reliability analysis of aerospace planetary roller screw mechanism considering multiple failure modes

“…Aurégan et al numerically calculated and experimentally simulated the motion and wear of the planetary roller screw [6], while Xing et al proposed a wear prediction model for the planetary roller screw mechanism, predicting the distribution of wear depth in the contact region [7]. Meng et al introduced roller errors and derived an accuracy loss model caused by wear [8]. Lepagneul et al combined the Hertz contact model with multi-axial fatigue criteria and proposed a fatigue failure judgment method [9].…”