Research Papers

Kinematics of Roller Migration in the Planetary Roller Screw Mechanism

[+] Author and Article Information
Matthew H. Jones

Steven A. Velinsky1

Department of Mechanical and Aerospace Engineering,  University of California, Davis, One Shields Avenue, Davis, CA 95616savelinsky@ucdavis.edu


Corresponding author.

J. Mech. Des 134(6), 061006 (Apr 27, 2012) (6 pages) doi:10.1115/1.4006529 History: Received July 21, 2011; Revised March 22, 2012; Published April 27, 2012; Online April 27, 2012

This paper develops a kinematic model to predict the axial migration of the rollers relative to the nut in the planetary roller screw mechanism (PRSM). This axial migration is an undesirable phenomenon that can cause binding and eventually lead to the destruction of the mechanism. It is shown that this migration is due to slip at the nut–roller interface, which is caused by a pitch mismatch between the spur-ring gear and the effective nut– roller helical gear pairs. This pitch circle mismatch can be due to manufacturing errors, deformations of the mechanism due to loading, and uncertainty in the radii of contact between the components. This paper derives the angle through which slip occurs and the subsequent axial migration of the roller. It is shown that this roller migration does not affect the overall lead of the PRSM. In addition, the general orbital mechanics, in-plane slip velocity at the nut–roller interface, and the axial slip velocities at the nut–roller and the screw–roller interfaces are also derived. Finally, an example problem is developed using a range of pitch mismatch values for the given roller screw dimensions, and the axial migration and slip velocities are determined.

Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

Roller screw and the relevant components [20]

Grahic Jump Location
Figure 2

Planetary gear dimensions, pitch circle mismatch exaggerated

Grahic Jump Location
Figure 3

Slip angle definition—Dashed lines are helical and solid lines are spur gear pairs, pitch circle mismatch exaggerated

Grahic Jump Location
Figure 4

Region of pure slip

Grahic Jump Location
Figure 5

Axial displacements and sign convention

Grahic Jump Location
Figure 6

Normalized total axial migration of roller, δRNTotalλ, as a function of pitch mismatch error, ɛ

Grahic Jump Location
Figure 7

Normalized slip velocity, υP on the left axis and υRN on the right axis as a function of pitch mismatch error, ɛ



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In