Hypocycloid is a parametric curve traced by a fixed point on a circle that rolls on the interior of another larger circle.
The curve - due to its parametric functionality - finds many applications, both theoretical and practical. They include mechanical and construction engineering, e.g. design of gears, cams, valves, robotics (motion planning), and machine/structures design in general. Contribute also to aesthetically pleasing art designs and animations.The hypocycloid curves can be generated quite easily in Excel with VBA macro, presented at the end of this post. Here are some examples of charts with generated hypocycloid curves, both single and combined double curves: