Embodied timing turns a robotic tug-of-war into cooperative transport

Relative timing of pull forces in a tug-of-war between two matched teams of spring-coupled robots breaks symmetry: the lagging team wins most strongly near a quarter cycle.

• Why it matters: It is unclear whether force timing alone can determine which side moves a shared load in antagonist systems.
• What they did: The study combines experiments, theory, and simulations of spring-coupled robot teams, comparing unison, strict alternation, and timing lags, and analyzing motor-current signatures.
• The result: In the model and robot simulations, braking between pulls (once strong enough) shifts advantage to the leading team, and local motor-current signals support a decentralized phase-adaptation rule for switching leadership to transport high-friction cargo and navigate to a target without communication.