Byte - Hero bot - Arm motor overheating

[dodsatya]

Hi, Our team has built the Byte hero bot for Full volume. The arm lift mechanism is built using two motors as given in instruction manual. Any idea on what could be the reason for the right side motor to overheat while the left motor does not show any sign of overheat?

[turbodog]

Several things, all of which you can test for.

1. check the motor amps in your code, you can display them to the brain’s screen. compare left/right motors, see if they are within 10% of one another.

2. confirm the 2 motors are actually working and working in tandem.

3. confirm the motors are set for the correct rotation direction. as they are on opposite sides, one of them will HAVE to have the rotation reversed

4. check the motors themselves… swap left/right, see if the overheating stays on the same side, or follows the motor.

[willjlong]

Is the motor stopping set to “Hold”? If so, that is probably the issue. Change to “Brake” or “Coast.”

[turbodog]

They need ‘hold’ to keep the arm in place.

Now if only 1 motor is set to ‘hold’… then it’s doing all the holding work and will get hotter. Check the code. Posting the code here would be better.

[Bas1124]

If your motors are overheating, make sure to take a break from driving or using that motor. I know this isn’t really helpful but i’m just here to make sure your motors don’t stop working during a match due to overheating.

[dodsatya]

Thanks for your feedback.

1. Checked the motor velocity of both motors and they are within 10% of one another
2. Velocity shows that both motors are working
3. Yes, one is set to normal and another one to reverse
4. swapped the motors…overheating still stays on the same side.

[dodsatya]

Thanks. this is definitely helpful. We learnt it hard way already fried one motor.

[dodsatya]

we referenced sample controller byte code.

when started

set armgroup = hold
set intake = hold

[turbodog]

Good work. Make sure to make a notebook entry on this. The problem’s not solved, but some things have been eliminated.

1. Are the arm motors working as a motor group?
2. If so, good. If NOT, drop the code in here… maybe they are not starting at the same time… which means one if moving and the other is holding (or trying to hold).
3. Pic of the mechanism would be good. You are ruling out electronic/code issues… so the chances this is mechanical is increasing.

[willjlong]

Not a solution to your problem, but a temp fix for overheating motors is to spray it with canned air. This will quickly cool the motor. You can get canned air (used for dusting off keyboards, etc.) most anywhere: Amazon, Office Depot, etc.

[willjlong]

Seems odd that the overheating stays on the same side. Wonder if you may have a bad cable to the brain? Are you sure the other motor (the one that is not overheating) is actually working when installed on the robot? When you did your testing, did you test both motors at the same time while installed on the robot.? Just spit balling here but you might try unplugging the overheating motor and then run a test to make sure the other motor in the motor group is actually working. You may have to “help” the arm to move.

You also might try moving both motors in the motor group to different ports?

[gbr]

The Hero bot builds (intentionally) give the students problems to work. I like that it gives many teams a place to start, while still delivering opportunities to learn.

If the problem is an engineering problem, instead of a ‘programming issues’:

It’s a good opportunity for the team to look at levers & fulcrums. The Byte Arm & Intake gives the team an excellent opportunity to solve some straightforward engineering issues.

VEX IQ Building Basics: Levers

The VEX Knowledge Base articles suggest using rubber bands to assist lifts in the 2nd paragraph, just below the video, that could give your team a quick win to overcome the issue by reducing the load on the motor:

Building VEX IQ Robot Arms

There may also be other opportunities to give the massive intake a diet to reduce weight. Lots of opportunities, etc…