Quote:
Originally Posted by GeeTwo
In our experience, you will definitely notice. This is what happens: - The current draw causes the RIO to "brown out" the motors.
- The voltage recovers.
- The system restores the motors.
- The motors draw inrush current.
- Return to step 1.
This results in a very distinctive "stutter" at about 15-20 jitters per second that gets the robot nowhere fast. |
My team last year definitely noticed this in our practice sessions, especially when trying to turn (scrub friction increasing the load on the motors). It happened after a few minutes of driving as the battery wore down, and of course it was worse when the robot was trying to move a stack of totes because of the added weight load. Our forklift design caused much of the weight of the totes to press down on the front two wheels.
We would start with a fresh battery, get in a few minutes of driving and stacking, then at some point try to turn the robot while carrying a stack and experience the CLACK-CLACK-CLACK-CLACK stutter which told us it was time to change the battery.
With a fresh battery for each match in competition we didn't notice it as much. We also did a MacGyver fix by applying duct tape to the treads of the two front wheels to reduce the scrub friction against the carpet.