mBot Mega motors not turning when unplugged

#1

My Mbot Meqa doesn’t work when I unplug it. The code runs and everything works fine when plugged into the computer and when I unplug it from the computer the lights change but the motors seem to not respond. When the motors respond they move maybe like an inch and nothing else. Yes I’ve tried new batteries I don’t know what the problem is.

#2

@Addon2
Just making sure:

  • The mBot Mega switch is turned on
  • You are using alkaline (normal, non-rechargeable) batteries
#3

Like @Best_codes said, I think you need to use alkaline batteries or the 18650 battery pack available via robotshop.com.

#4

Yes, the switch is turned on and we’re using normal batteries.

#5

I see but the problem is I believe we are just not getting enough volts from the batteries, we’re using 6 double a batteries. Is there another pack that can hold bigger and better batteries?"

#6

I find this discussion interesting because it reveals a lot of uncertainty about battery status. Shouldn’t there be a way build into the system to verify adequate voltage.

#7

@Addon2
A USB cable usually puts out about 5 volts. 6 AA batteries is 9 volts. So it does not make sense that it only works when plugged in!

So, have you uploaded a code to the mBot Mega to turn the motors? Be sure to actually upload the code in upload mode, not just use live mode. Live mode only works when your device is plugged in.

#8

Yes we’re uploading everything correctly.
It worked before then we added more code which caused it to stop working.

#9

@Addon2
What did you change in the code? That could be the cause of it not working.

#10

Nothing that I know of, all we did was add code so the controller will work.

#11

@Addon2 Did you add an extension for this, I’m assuming? Does the robot work with a fresh code and no extensions?

#12

We did have to add the controller extension.

#13

I figured it out the power output to the motors were too high.

#14

Any idea why this would cause them to not spin? Did it ruin the motors?

#15

No, Idea really all we did was cut the power to the motors by 50%. The motors work fine now. If we unplugged the wires to two of the motors it would allow the mbot mega to run again normally.