Fig. 5. The locomotive force in (A) the horizontal and (B) the vertical directions. Squares: calculated locomotive forces. Error bars indicate uncertainty from measurement and evaluation. Solid line: spline fitting of the data. Note that due to limitations on integration time, these plots are based on the first 400 ms of a 600 ms fin beat cycle. Adapted from Peng et al. (Peng et al., 2007).