A Review of Research on Travel Error in Planetary Roller Screw Mechanisms

Planetary roller screw mechanisms (PRSMs) are critical transmission components in high-end equipment and precision electromechanical systems, and their travel error directly affects motion accuracy and operational stability. This review systematically examines the main sources and research progress of PRSM travel error, including manufacturing and geometric errors, installation errors, load and thermal deformation errors, and service and environmental factors. It further reviews the current state of research on travel error models, with emphasis on travel error modeling and dominant error identification. Existing measurement methods are classified into static measurement, dynamic measurement based on linear encoders or laser interferometers, machine vision measurement, and auxiliary methods for specific operating conditions, and are compared in terms of accuracy, applicable test objects, and engineering limitations. The review shows that current studies have established an important basis for travel error prediction, compensation, and test system development, but limitations remain in experimental validation, dedicated test rigs, component-level measurement of roller external raceways and nut internal raceways, and unified evaluation standards. Future research should develop specialized measurement systems that consider multi-contact characteristics, representative loading conditions, backlash elimination, error separation, and data compensation to support high-precision PRSM applications.