What a tow loses by not being straight

Axial stiffness kept, against the crimp of the tow, for two reinforcing fibres, with one wavelength of the tow's own path inset above it — drawn to scale, so that the tangent at its steepest point is at the true angle and the gentleness of the path is the finding. The tow is treated as a stack of infinitesimal off-axis plies whose compliances add in series — Ishikawa and Chou's crimp model, 1982 — so the loss is largest where the path is steepest and nothing at the crowns. Neither axis carries a wavelength, because the wavelength cancels: the knock-down is a function of the crimp alone.

1 essay calls knockdown. The drawing above is what it returns with no arguments at all; every call below passes it something, because a placement that passes nothing draws whichever member of the family the generator happens to default to rather than the weave its essay argues about.