Best way to control the mechanum wheels

[Greg McKaskle]

During the season, or in the offseason, you can modify, rewrite, or replace any of the libraries above the FPGA access libraries. Since writing that from scratch would literally take you years, may I suggest learning to read the code that is there.

FYI, one of my biggest turn-offs when interviewing job candidates is the NIH syndrome. NIH == Not Invented Here. It seems to be a phase all programmers and engineers go through, but almost nobody is productive enough to be able to compete well until they get over it. Learn to read, debug, analyze, criticize, praise, understand, extend, and communicate the designs of others. It will serve you well.

You cannot modify the FPGA. That would remove the ability for FIRST to control the outputs and provide a safe experience for team members, volunteers, etc.

Greg McKaskle

[pfreivald]

Last year we used mecanum to great success, using two joysticks. One joystick controlled movement direction, and the other controlled rotation -- exactly like a 1st person shooter played on Xbox.

While it wasn't an Xbox controller, our driver could think of it as one, and he had an intuitive knack for it very quickly.

[tomy]

So it's not hard to do it in c++?

[davidthefat]

Originally Posted by tomy

So it's not hard to do it in c++?

No not at all, the mechanum drive would only take 5 lines MAX. (excluding the header file and PWM regulation)

[tomy]

Wow thanks I can wait to try it out

[davidthefat]

Originally Posted by tomy

Wow thanks I can wait to try it out

Actually I lied, more like 8-10 but you get the point. Good luck, if you need any help ask.

[Nemo]

You get a holonomic drive VI with the Labview libraries. All you have to do is plug your three joystick axes into that VI, and it gives you the output levels for each of the four drive motors.

[KHall]

Which develpment environment are you planning to use?

If its LabView, the VIs are all supplied. You'll have to do some problem solving to convert the joystick's output (or any other kind of steering device) to the inputs that the mechanum VI requires.

I can vouch for the LabView VI. We used it last year, it works great. And we've done mechanum wheels 3 of the last 5 years. Like anything else, there are tradeoffs to consider.

Keith Hall
Mentor FRC 2171, FLL 1528

[XaulZan11]

Originally Posted by davidthefat

Now I personally have no experience with mechanum drive

There are enough people here that do have experience with mechanum drive and have learned from those experiences. As it is with rules questions, only post when you are positive you are correct opposed to what you think is right. (I try to practice this and if you notice, I rarely, if ever, post in technical threads )

PS: for all I know, what you said was 100% correct and if so, I apologize.