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arXiv · 2609.19194

AthenaZero: A low-inertia, bimanual robot for dynamic manipulation

Abstract

AthenaZero is a bimanual manipulator designed to minimize inertia without compromising control authority. By utilizing quasi-direct drive actuation and transmission remotization techniques, the system achieves an effective endpoint mass comparable to that of a human---about an order of magnitude less than conventional robot manipulators. This characteristic, combined with its inherent torque transparency, makes AthenaZero exceptionally well-suited for dynamic manipulation. We describe the methodology} that led to this design and demonstrate the robot's capabilities on three baseball-inspired tasks: throwing, catching, and batting, which showcase complex interactions on human-comparable timescales where milliseconds matter. AthenaZero was capable of throwing at speeds in excess of 30 m/s, with catching and batting at speeds in excess of 14 m/s over a short 7.3 m distance. Batting practice and a game of catch were subsequently performed in robot-to-robot and human-to-robot variations, showcasing the efficacy and adaptability of our system in tasks that require high acceleration.

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Andrew S. Morgan, Gregory Xie, Capprin Bass, Rachel Thomasson, Chunpeng Wang, Erfan Shahriari, Harrison Busa, Oluwaseun Araromi, Joseph Aronov, Michael Burgess, Velin D. Dimitrov, Matthew A. Estrada, Faris Hamdi, Samuel Kendig, Taeyoon Lee, Jose Oscar Mur-Miranda, Emma Sommers, Paul Titchener, Margaret Wang, Achu Wilson, Mark Yeatman, Osman Dogan Yirmibesoglu, Alfred A. Rizzi, Annan Mozeika, Nicolas Rojas, Lael Odhner. 2026-09-15. AthenaZero: A low-inertia, bimanual robot for dynamic manipulation. https://doi.org/10.1126/scirobotics.aee1868

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