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arXiv · 2509.07437

GRASPion: an Open-Source, Programmable Brainbot for Active Matter Research

F. Novkoski·M. Mélard·M. Delens·F. Wéry·M. Noirhomme·J. Pande·A. Maier·A. -S. Smith·N. Vandewalle
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Abstract

We present the GRASPion, a compact, open-source bristlebot designed for the controlled study of active matter systems. Built around a low-cost Arduino-compatible board and modular 3D-printed components, the GRASPion combines ease of use, programmability, and mechanical versatility. It features dual vibrating motors for self-propulsion, integrated sensors for local interaction, and customizable firmware enabling various motion modes, from ballistic to diffusive regimes. The robot is equipped with onboard IR communication, color and proximity sensors, and a magnetometer, allowing for real-time interaction and complex collective behaviors. With a runtime exceeding 90 minutes and reproducible fabrication, the GRASPion provides a robust and scalable platform for both educational and research applications in out-of-equilibrium physics. This article details the mechanical and electronic design and software architecture of the GRASPion, and illustrates its capabilities through prototypical experiments relevant to active matter.

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F. Novkoski, M. Mélard, M. Delens, F. Wéry, M. Noirhomme, J. Pande, A. Maier, A. -S. Smith, N. Vandewalle. 2025-09-09. GRASPion: an Open-Source, Programmable Brainbot for Active Matter Research. https://arxiv.org/abs/2509.07437

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