#13 Extract all the 2D coordinates

[Mitch]

Hi,

I'm a graduate student in mechanical engineering. The following question may appear trivial and I thank you for your time to make this package public.

I wonder if I can extract the coordinates of the spur gear outter circumference?

The formcoordinate only gives the half tooth. I wonder if I can have access to all the coordinates (2D)?

Thank you.

[Joana]

as the coordinates of half a tooth contain all the geometric 2D-information, there is no function to write out all the coordinates in pygear. However, it is easy to generate all the coordinates from the half-tooth coordinates by yourself (e.g. by writing a small script in Python or Matlab).

1. mirror the half tooth (same y-coordinates, negative x-coordinates), reverse the order and attach it to the original coordinates --> full tooth
2. rotate full tooth by phi=n*360/z degrees and attach it to the coordinate vector (where z is the number of teeth and n is an index running from 1 to z-1). Rotation is done by multiplying each coordinate vector by the the matrix [cos(phi), sin(phi); -sin(phi), cos(phi)]
3. repeat 2. z-1 times until you have the full gear