Cycloid scales appear to be the inner layer of ganoid or cosmoid scales. Found in carps and similar fishes, they are thin, large, round or oval, and arranged in an overlapping pattern; growth rings are evident on the free edges.

How do you find a cycloid?

cycloid, the curve generated by a point on the circumference of a circle that rolls along a straight line. If r is the radius of the circle and θ (theta) is the angular displacement of the circle, then the polar equations of the curve are x = r(θ - sin θ) and y = r(1 - cos θ).

What are the applications of cycloid?

An epitrochoidal cam constrained to perform a wobble motion, used in conjunction with a stationary mangle gear, constitutes a highly efficient, compact speed reducer. Other examples of the application of cycloidal motion are function generators, indexing devices, pumps, straight-line linkages, etc.