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arXiv · 2510.07197

COMPAct: Computational Optimization and Automated Modular design of Planetary Actuators

Aman Singh·Deepak Kapa·Suryank Joshi·Shishir Kolathaya
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Abstract

The optimal design of robotic actuators is a critical area of research, yet limited attention has been given to optimizing gearbox parameters and automating actuator CAD. This paper introduces COMPAct: Computational Optimization and Automated Modular Design of Planetary Actuators, a framework that systematically identifies optimal gearbox parameters for a given motor across four gearbox types, single-stage planetary gearbox (SSPG), compound planetary gearbox (CPG), Wolfrom planetary gearbox (WPG), and double-stage planetary gearbox (DSPG). The framework minimizes mass and actuator width while maximizing efficiency, and further automates actuator CAD generation to enable direct 3D printing without manual redesign. Using this framework, optimal gearbox designs are explored across a wide range of gear ratios, providing insights into the suitability of different gearbox types while automatically generating CAD models for all four gearbox types with varying gear ratios and motors. Two actuator types are fabricated and experimentally evaluated through power efficiency, no-load backlash, and transmission stiffness tests. Experimental results indicate that the SSPG actuator achieves a mechanical efficiency of 60-80%, a no-load backlash of 0.59 deg, and a transmission stiffness of 242.7 Nm/rad, while the CPG actuator demonstrates 60% efficiency, 2.6 deg backlash, and a stiffness of 201.6 Nm/rad. CODE: https://github.com/singhaman1750/COMPAct.git VIDEO: https://youtu.be/etK6anjXag8?si=jFK7HgAPSBy-GnDR

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Aman Singh, Deepak Kapa, Suryank Joshi, Shishir Kolathaya. 2026-04-01. COMPAct: Computational Optimization and Automated Modular design of Planetary Actuators. https://arxiv.org/abs/2510.07197

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