Locomotion

Flight Phase

A flight phase is an interval during legged locomotion in which no part of the robot contacts the ground, occurring in dynamic gaits such as running, trotting with suspension, pronking, and jumping. During flight the center of mass follows ballistic dynamics that no ground force can alter, so the controller can only reorient limbs and body angular momentum to prepare touchdown conditions. Flight phases make gait timing and landing control critical.

Why it matters for physical AI

Dynamic gaits with aerial phases are essential for speed and obstacle negotiation, and their underactuated ballistic dynamics stress-test learned locomotion policies far beyond quasi-static walking.