Is there an equation for sinusoid about a curve?

1. Jul 6, 2011

corona7w

The typical sine wave y = sin(x) has its center line as y = 0. Is there any equation I can represent a sine wave that has a center line as a curve? Something like the edge of the cookie cutter:
http://www.pmeartsandcrafts.com/4010-16826-large/round--wavy-edge-cutters-xxxl.jpg [Broken]

Last edited by a moderator: May 5, 2017
2. Jul 6, 2011

Sourabh N

You basically need a sine wave along a curved dimension. Here is one function that achieves this.

r = a - b*cos(w*t)
a is the radius of center circle.
b is the amplitude of sine wave.
w is the frequency of the wave. I chose integer value for w to make sure the sine wave ends where it started.
t is the angle, goes from 0 to 2pi.

Here is an http://shareimage.org/images/uh7fobqbcznu724zhu.png" with a = 5, b = 0.5, w = 10.

Last edited by a moderator: Apr 26, 2017