Drivetrain drift problem

VEX IQ General Discussion
21

I can’t believe nobody’s mentioned this at all, but have you ever considered fixing this in the code, as this is only a big problem in skills?

IQ participants have posted drive-straight PID tutorials on YouTube
https://www.youtube.com/watch?v=YkUDSFs0m4U
And this might be helpful:
https://www.youtube.com/watch?v=4Y7zG48uHRo

22

If you use the inertial to get the heading you can sense if it went of track. Then you can turn it back.

23

My team had this problem last year too. Our troubleshooting went like this:

  1. Make a program that will print the speeds of the left and right motors periodically(maybe every second) and see if they are the same.
  2. Take the motors off the shaft and see if they are the same.
  3. For our drivetrain, on step 1, the speeds were very different and on step 2. They were somewhat the same.
  4. Then we scrutinized our drivetrain carefully(some things are hard to see) and realized that the two halves of our drivetrain had slightly different mechanisms for extending the shafts(they were build by different people).

In addition, if your field is unlevel, if you drive it the other way, it will drift to the left.

Hope that helps!

24

Update: the field is even; The robot still drifts in other locations.

25

I would suggest a four wheel drive with some static wheels

26

We had the same problem last year in V5, hopefully our solution works for you guys!

We had the same problem last year, our field was even, we had rebuilt our drivetrain, all motors were fully functional and were using the same wattage. After much experimentation we learned that our problem was caused due to one of our right motors overheating and slowing down by around 48%. I’m not too familiar with IQ motors, but I’m assuming that like V5, there is no exhaust on the motors and they are prone to overheating after being run for more than 3-5 minutes. In order to correct this, we first determines which motors were overheating quickly and used a spray can to cool down the motors before and after each match.

Hope this works! - 11865A

27

Our IQ motors were not overheated, however, it could be a problem with the motors. I will do a few tests to see this.