Holonomic Drive System Issues, Robot Drives Diagonally...

[AllenGregoryIV]

Yes, hopefully at some point we will be on the same alliance at Alamo. I think we will definitely give the other alliance some problems. They will be trying to figure out which way we are going and only we will know

See you guys in 8 days.

[Andrew Schuetze]

I keep envisioning a pivot move aka some great NFL running back that is heading down field and spins around a defender or your favorite NBA point guard for a driving layout

What would it take to program such a spin around either the front right or front left wheel We currently have drive/strafe and then zero degree spin coded to two joysticks. Maybe it is just driver control with drive input coming from one joystick and a spin componant coming from the other....

[Ether]

Originally Posted by Andrew Schuetze

What would it take to program such a spin around either the front right or front left wheel

The math is not that hard. See attached image.

Calculate how fast you want to rotate. Call that omega. That's your rotation command. Multiply omega by |AC|. That's your translation magnitude. Theta is your translation direction angle. Translation velocity vector V is perpendicular to |AC|.

[AllenGregoryIV]

The way we do it is with driver practice. To be able to pivot you have to give the robot some rotation (in our set up the x axis of the drivers right hand) and move the robot in an arc which is to keep the y constant while moving the x from positive to negative (this happens on the left stick).

We were also trying to figure out if the driver could drive around the minibot pole while holding orientation to the pole. This is not easy in our current control scheme but possible you have to make a circle with left joystick and hold a constant rotational velocity with the right one.

This is all with field centric control. Without that the first move becomes much harder while the second is much easier.