Hello
We have a 4 motor V5 drive at 600 RM for a demonstration robot. While driving it around for about 6 minutes we noticed that the speed was significantly reduced. As a team new to V5 this year, we were wondering why this is?
The motors felt kinda hot and there were nothing getting stuck from a mechanical aspect
Seems like the motors were running at full speed under load for 6 minutes and started to get hot. V5 motors have temperature sensors and most likely throttled to prevent damage from overheating.
4 V5 motors at 600 RPM is not enough power to drive a robot for too long. Your motors will burn out and your robot will slow down.
So it good that there was a reduction in power Due to temp. Just wondering does this happen during a 2 min match?
It would depend, do you drive the whole time. How much are the motors heating up. If you are driving a heavy robot the motors will heat up faster…
Personally my team never had the problem of motors overheating during a match.
Also with v5 motors your program can get stuff like the motor temperature and current.
I am by no means an expert, but last season, out puncher would stop working after excessive use but after charging our battery, it was fine. After a while, the motors start to lose either speed or power. Just recharge the battery and you’ll be fine.
Did you use v5 or legacy? The v5 isn’t supposed to decrease in power when the battery gets low.
How heavy was the robot?
My bet would be that your motors are cooling down while the battery is charging.
V5
20 characters sucks
It was a about 4 lbs
Only 4 pounds, so your robot basically only had a drivetrain, then it should have been fine, maybe you were suddenly jolting the joystick back and forth?
I was driving it on concrete floors and was not driving the way I would in competition
I’m not sure how that would have an impact, however there could of been static on the floors, and as the robot drives it picks up static, causing the motors to die out.
Because V5 motors are way more powerful than their cortex counterparts, they tend to heat up a lot faster when they are put under stress. After about 5-10 minutes of straight practice, my intake and lift motors are already quite hot. I recommend you add some code that will notify you when your motors are overheating, as the motors can actually sense their temperature. This has saved us a lot of money by allowing motors to cool before they are irreversibly damaged.
Would y’all recommend using a compressed air can to spray the motors?
Compressed air does cool the motors, but I would use it sparingly, as you are only cooling the shell around the motor itself (unless you open the motor up and spray it inside). Also, the propellant in compressed air cans (the cold white mist that comes out when you spray upside-down and what most use to cool the motors) is quite toxic and contains a bitterant to prevent people from inhaling too much. If you end up using it, just be careful and sensible about it.
If you have time i recommend unplugging the motor and letting it sit for 10-15 mins, check with your hand to see if its closer to room temp by then.
So during a match when we drive for 1:45, will the with like 10 cubes, how will the motors react
Edit: during this instance I was driving the robot in a manner very far from the way I would drive at a comp. like I was switching my joystick either direction very quickly
You can also set your own current limits for the motors that are lower than the defaults. (Example in Robot Mesh Studio.) Because the heat produced by a motor is related to its current draw, limiting the current draw will limit the heat production. However, it will also limit the maximum torque available to the motor, so you might accelerate more slowly as a result.