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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%.