Anti-Backlash Mechanisms for Cycloidal Drive Robotic Actuators: Design and Evaluation
Wesley Roozing, Jelmer Volbeda
AI summary
Problem
Backlash in high-efficiency cycloidal drives compromises control accuracy in dynamic legged robots, yet few compact, cost-effective anti-backlash solutions exist for these actuators.
Approach
The authors designed and integrated two adjustable anti-backlash mechanisms (a conic disk and a split pinwheel design) into a motor-embedded cycloidal quasi-direct drive actuator, then experimentally evaluated their performance across varying preload levels.
Key results
- Developed a cost-effective, 3D-printed quasi-direct drive actuator with motor-embedded cycloidal gearing
- Designed two novel adjustable anti-backlash mechanisms for cycloidal reducers
- Experimentally demonstrated 2-3x backlash reduction with <2x friction increase across varying preload levels
- Identified a stiffness trade-off in the split pinwheel design as preload increases
Why it matters
Provides legged robot developers with practical, low-cost actuator designs that improve positional accuracy without severely sacrificing efficiency.
Abstract
We design and experimentally evaluate two anti- backlash mechanisms for cycloidal reducers. The two mech- anisms are integrated into variations of a proposed design of quasi-direct drive actuator. Three prototypes are realised to compare the two mechanisms against the baseline design. We evaluate the effectiveness of the anti-backlash mechanisms under varying preload with measurements of friction, backlash, and stiffness. The results demonstrate that the anti-backlash mechanisms are effective at reducing backlash by approx. 2- 3x, at the expected expense of increased friction (<2x).