Fig. 7. (A) Non-dimensional power and thrust versus strip length. Non-dimensional power and thrust are calculated by multiplying the power or thrust coefficient by strip length and unit width (w=1) and dividing by amplitude squared. (B) Efficiency versus strip length. (C) Total thrust produced versus average chord length for rectangular wings. (D) Whole-wing efficiency versus average chord length for rectangular wings. Each point in parts C and D represents the performance of a single wing with the given average chord length. For all graphs, U=0.15ms^-1, c=0.3ms^-1, H=0.058m and f=2.27s^-1. U, velocity; c, wave speed; H, fin tip amplitude; f, flapping frequency; C_P, power coefficient; C_T, thrust coefficient; h₀, amplitude; l, strip length.