Extended Data Fig. 7: Wingbeat amplitude variation in M. sexta simulations.
From: Bridging two insect flight modes in evolution, physiology and robophysics

a) The three plots show the wingbeat angle versus time at three different values of t0/Tn, for a constant Kr = 0.2 (parameters for tests i, ii, and iii are shown in panel b). After transient oscillations die out we measure the amplitude of wingbeat peaks as a function of time (positive peaks are shown as red triangles). The top plot is an example in the asynchronous regime, displaying moderate amplitude fluctuations. The middle plot is the wing angle within the frequency locking synchronous regime (on the “bridge”) where the wing amplitude is steady. Lastly, the bottom plot shows the wing motion in the asynchronous regime below the frequency locking “bridge”. b) For all combinations of Kr and t0/Tn we calculated the standard deviation of the wingbeat amplitudes which we show as a heatmap. Brighter regions of the plot correspond to where large stroke to stroke amplitude variation occurs (i.e. top and bottom plots in panel a). When the wingbeat is steady the amplitude variation is small these appear as the black regions. The boundaries between the synchronous and asynchronous regimes exhibit large amplitude fluctuations, while the bridge connects the synchronous and asynchronous regimes with smooth sinusoidal emergent wingbeats.