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arXiv · 2610.09645

Design optimization of tendon-driven robots considering tendon wrapping and shortcut

Yuta Sahara·Kento Kawaharazuka·Kei Okada
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Abstract

This study proposes a multi-objective optimization method for tendon-driven arm design, addressing the inherent trade-off between joint torque and arm thickness through tendon wrapping and shortcut effects. We formulate the problem to simultaneously maximize torque and minimize thickness, solved using NSGA-II. The algorithm optimizes tendon routing, pulley configurations, and attachment points. Results reveal Pareto-optimal designs with effective moment arm expansion via strategic shortcuts, providing practical guidelines for compact high-torque arms. The optimized configurations demonstrate non-trivial patterns beyond conventional design intuition, offering new insights for engineering efficient robotic systems.

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Yuta Sahara, Kento Kawaharazuka, Kei Okada. 2026-10-07. Design optimization of tendon-driven robots considering tendon wrapping and shortcut. https://doi.org/10.1080/01691864.2026.2723650

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