Oscillating Eel Robots That Leverage Collisions for Controllable Motions

Abstract

We introduce a platform of oscillating eel-like robots that exploits physical collisions to enable controllable collective behaviors. Each robot is actuated by a Kuramoto-style central pattern generator, and produces undulatory motion that passively synchronizes through collisions with neighboring robots and a surrounding rigid membrane. Instead of avoiding collisions, the system leverages robot-robot and robot-environment interactions to bias collective forces and torques. Using motor current as a surrogate for joint torque, we analyze how actuation parameters enable specific collective motions, and by tuning a small set of global central pattern generator parameters and selectively locking joints or robots, the collective can be programmed to exhibit clockwise and counterclockwise rotation, orbiting with adjustable curvature, and directed translation. We further demonstrate that the collective behaviors can be switched between on demand to enable trajectory following, obstacle avoidance, and object manipulation.