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Updated: Jan 18, 2026

Operation of the Collaborative Composite Manufacturing CCM System
Published on: October 1, 2019
A geometric condition for robot-swarm cohesion and cluster-flock transition
Mathias Casiulis1,2, Eden Arbel3, Charlotte van Waes4
1Center for Soft Matter Research, Department of Physics, New York University, New York, NY 10003.
Abstract:
We present a geometric design rule for size-controlled clustering of self-propelled particles. We show that active particles that tend to rotate under an external force have an intrinsic, signed parameter with units of curvature which we call curvity, that can be derived from first principles. Experiments with robots and numerical simulations show that properties of individual robots (radius and curvity) control pair cohesion in a binary system, and the stability of flocking and self-limiting clustering in a swarm, with applications in metamaterials and in embodied decentralized control.
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