Similar to the approach shown in Curves & Tangents, but here the generating curve is more complex: different cos/sin cycles with random radii, frequencies and phases are added to a point moving from left to right, basically following these equations:

with n = 2, 3 or 4. I generated many of these curves with random parameters - leading to a wide variety of curse - and selected some I found interesting below.

In the meantime I found or refound the work of David Chappell that seems very similar - and beautiful!