||This section features the
also known as the
hypocycloid of four cusps,
and still other names.
In one quadrant, the astroid may
be thought of as a falling ladder,
a problem often found in
introductory Calculus. In this
case, the curve is also
known as a glissette.
Yates writes the cycloidal curves,
the Astroid, were discoverd by Roemer (1674) in his search for the best
form for gear teeth. The equation can be found in Leibniz's
correspondence as early as 1715 and was further investigated by Daniel
Bernoulli in 1725. We suggest you also view the
cyloid of three cusps.