Fig. 8. Descriptive viscoelastic model fitted to the lateral recovery of cockroaches. (A) Voigt model for the mechanical behavior of cockroaches in the lateral direction. (B) Measured and calculated acceleration for a representative trial. The blue curve shows measured acceleration during recovery from a perturbation, and the red curve shows acceleration calculated from the Voigt model fitted to the cumulative trial data. The magenta curve shows the contribution of velocity-dependent acceleration (the damper) to calculated acceleration. The green curve shows the contribution of position-dependent acceleration (the spring) to calculated acceleration. The mean percentage error for the spring component alone for this trial was 40%, that for the damping component alone was 88% and that for the Voigt model was 17%.