Signal Velocity in Oscillator Networks

We investigate a system of coupled oscillators on the circle, which arises from a simple model for behavior of large numbers of autonomous vehicles. The model considers asymmetric, linear, decentralized dynamics, where the acceleration of each vehicle depends on the relative positions and velocities between itself and a set of local neighbors. We first derive necessary and sufficient conditions for asymptotic stability, then derive expressions for the phase velocity of propagation of disturbances in velocity through this system. We show that the high frequencies exhibit damping, which implies existence of well-defined signal velocities $c_+>0$ and $c_-<0$ such that low frequency disturbances travel through the flock as $f(x-c_+t)$ in the direction of increasing agent numbers and $f(x-c_-t)$ in the other.

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