Arduino Micro with Talon SR

[GeeTwo]

Originally Posted by AdamHeard

Depending on how fast all this is running (and what else is going on) using floats may be out of the question due to the slower math.

I did say ideally!

I'm fully aware of the need to program for integers in some cases. I even wrote a fully integer semi-swerve drive inverse kinematics a few years ago. My semi-swerve platform was about 1/3 FRC scale, with a 0-180 degree maximum steering angle steered by servos, and 25mm 1000rpm gear motors for drive, and yes, it was controlled with an Arduino. Unfortunately, the only hard drive that the code was on has since died. The key was that I wrote a hypoti(x,y) subroutine that calculated an integer hypotenuse using max(x, y) and the ratio 256 * min(x,y) / max(x,y) (where x and y were preprocessed to be non-negative), and an atan2id(y,x) that returned atan2(y,x) in degrees based on the same ratio, whether abs(x) or abs(y) was larger, and the two input signs. IIRC, the atan2id() routine had two separate cubic fits to cover the span from 0 to 45 degrees, that broke based on whether 2*min(x,y)/max(x,y) was 0 or 1 (that is, at about 28.8 degrees).