Experimental paradigm and simulation framework to investigate physical interaction between humans mediated by the coupling dynamics.

<p>(A) Experimental configuration to test physical interaction in 1 dimension. Subjects, recruited in pairs, were separated by a curtain and followed a common target using their wrist flexion/extension to control a cursor along a 1 dimensional arc. Their wrists were virtually coupled together through the dual robotic interface by a spring with computer-controlled elasticity. Only the target, which was a normally distributed cloud of spots, and one’s own cursor were displayed on each subject’s individual monitor. (B) The computational framework to test different strategies (in purple) that partners could adopt during interaction. In this approach, only the goal or what information is used to track the target is changed. The goal is tracked by a subject who generates a motor command to move their wrist. Two subjects are simulated in parallel, who experience the coupling force from the spring. In <i>follow the leader</i>, subjects switch to following the partner nearest to the target. In <i>interpersonal goal integration</i>, the partner’s target is inferred through haptics and is integrated with one’s own target estimated from vision. <i>Neuromechanical goal sharing</i> is similar to <i>interpersonal goal integration</i>, but the weighting between the visual target and the partner’s target is influenced by the coupling dynamics.