[Sharing] rotation function for an elliptical gear

[Mfroehlich]

Hi

just wanted to share an information I got from Art on a question I sent via mail. I needed the rotation-angle for the slave-wheel of an eliptical gear-couple:

To figure out the rotation of an ellipticals mate, I use an integration formula, which can be hard to use in
a spreadsheet..

dist = major axis radius.
double inc = .0005;
double total = 0;

for( double a = 0; a <= ang; a+= inc )
{
double r1 =&nbsp; "Elliptical radius at "inc" angle" ( From formula I sent earlier).
total += (r1 / ( dist - r1))*inc;
}
Gear#2 angle =&nbsp; total + PI - ( PI/&nbsp; m_Order);

BUT... you may find this following method far easier... The following formula
will work for an elliptical order 1 meshed to another order 1

Ang2 = the rotation angle of Gear#2
Ang1 = the master gears rotation angle.

Plug your values in this and youll get a very quick and accurate result.

Ang2 = atan(( 1 + e) / ( 1 - e) * tan(Ang1/ 2))*2;

This helped me to create my own gear-simulation inside blender with the help of drivers.

May this information be helpfull for others...

cheers

martin