Design and Evaluation of High-Performance Motion-Decoupled Cable Transmission Modules
Ryo Takei, Samuel Frishman, John P. Whitney
Abstract
Cable transmissions are commonly used in robotics for remote force transmission, offering a lightweight, compact, and efficient solution for transmitting high forces between input and output. However, cables in flexible compression housings (Bowden cables), exhibit high static friction, which increases exponentially with total bend angle. Alternatively, internally routed ball-bearing supported cable capstan transmissions are low friction, but complex and present challenges in routing multiple sets of cables. In this paper, we propose motion-decoupled cable transmission modules that address these challenges, occupying the middle ground, functioning as discrete-joint ball-bearing supported Bowden cables. Our rolling-plus-twist joint design decouples pairs of routed cables from changing significantly in tension, length, or friction during large angle motion of the linked transmission. Using sub-1 mm diameter high-strength synthetic cable, the transmission exhibits a maximum coupling motion of only 0.15 mm over the full range of motion of the cable-transmission mechanism, approximately 10% of pretension in combined hysteresis and friction, a transmission stiffness of 10 N/mm, weighing just 9 g per rolling joint and 5 g per twist joint. Two applications are demonstrated: cable routing alongside a robot arm for, say, gripper remote actuation, and remote needle advancement for an MRI-safe needle biopsy robot.
BibTeX
@inproceedings{icra2025_designandevaluat,
title = {Design and Evaluation of High-Performance Motion-Decoupled Cable Transmission Modules},
author = {Ryo Takei and Samuel Frishman and John P. Whitney},
booktitle = {ICRA 2025},
year = {2025}
}