My team’s robot for over under has a catapult for launching tri balls over the bar. It works with rubber bands and a gear with some teeth filed off to release the catapult. At school, our robot is almost completely consistent, missing maybe 1 or 2 out of 2 boxes of tri balls. When we got to the competition, before our first match we did a dry fire to make sure the gears didn’t slip like they had done before. They didn’t, and we turned the brain off and waited for our first match. When we got to the match however, the motor suddenly wasn’t outputting enough force to pull down the catapult. Are there any obvious reasons of why this could be happening?
There are a few reasons why:
- Overheating (put your hand on the motor to feel its temperature)
- Static discharge (go to the brain screen, then devices and see if your motor shows up)
- Someone at the comp hit you and knocked the wires/pins loose (same check as number 2)
- Mechanical issues (collisions knocking screws loose, wire tangles, etc.).
Try swapping them with new motors, and if that doesn’t work try using a different port. If this doesn’t work, try taking all the bands off except 1 and dry fire the catapult to see if there’s nothing jamming it.
Last note: did you change any part of your code before that first match?
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The problem isn’t the motor completely stopping or the axle coming out of it, the problem is that whenever we get to the competition it suddenly stops being able to pull all the way down. It can get to the last couple teeth of the gears, but it suddenly isn’t able to push over to where it needs to be.
Also, when we got to class we decided to test it. Without any changes between now and the competition, it works just fine.
Did you change your rubber bands for new ones before the first match? If you did, the rubber bands could’ve been too strong for the motor to pull down. Try using used rubber bands; many teams at my school found they work better than new ones.
The motor also might’ve been overheating. Using volts instead of velocity percent in your code will output the exact volts every time, rather than turning down the velocity when overheating.
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We did not change the rubber bands before the match. I know the motors can overheat but I don’t think that’s our problem because before our first match we only tested it once, while in class we got it to launch 10-20 times in a row and the motor still didn’t reach a temperature that I would call “hot.” I will see about making the code use volts instead of % when I get to class.
Also to answer the question from your previous response, we did not change the code before our first match.
VEXcode V5 doesn’t have the option to use volts instead of velocity.
Yes it does, there’s just no autofill. You have to do it manually.
We aren’t using that (version? type?) We are coding with the drag and drop things.
Oh blocks… yeah then I don’t think you can do volts.
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