Sample data from a 225° perturbation. (a) Magnitude of R COP and (b) Phi are shown as functions of time, indicating peak values (Rmax, Phimax), peak times (Tcop, Tphi), recovery time (Trec), and time to peak recovery velocity (Tvel). DZ indicates the degree of tilt within which no tactors are activated. The three stages of the trajectory are marked as I, II, and III for panels (a) and (b). (c) X and Y components of COP are shown in a bird’s-eye view with the peak time (black filled circle) and angle (dashed line), as well as the platform motion (blue arrow). (d) A/P and M/L components of tilt are shown in a bird’s-eye view with the peak time (red circle) and angle (dashed line), Tvel (yellow filled circle), and Trec (green filled circle).