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arXiv · 2503.20702

CyberDiver: an untethered robotic impactor for water-entry experiments

John T. Antolik·Eli A. Silver·Jesse L. Belden·Daniel M. Harris
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Abstract

We present the CyberDiver, an untethered robotic impactor capable of actively modulating the fluid physics during high-speed water entry. First, we utilize the CyberDiver to extend our understanding of the water entry of passively flexible systems, designing a high-bandwidth controller that enables the CyberDiver to operate as a cyber-physical system that permits an arbitrary programmable structural coupling to be experimentally tested. Onboard sensors record the body acceleration during impact and reveal that the introduction of damping or a nonlinear force-versus-displacement structural law can significantly reduce impact loading as compared to a linear elastic case, with implications for damage mitigation in aerospace and naval applications. Next, by operating the CyberDiver in a displacement control mode, we demonstrate that the splash size can be dramatically altered depending on the parameters of an active maneuver, laying a groundwork for better understanding the techniques of human competitive divers.

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John T. Antolik, Eli A. Silver, Jesse L. Belden, Daniel M. Harris. 2025-03-26. CyberDiver: an untethered robotic impactor for water-entry experiments. https://arxiv.org/abs/2503.20702

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