mBot 2 Rover motors cause instant shuts down

#1

Hello! My son and I built the mBot2 Rover Robotics Kit. We downloaded the ‘main program’ and uploaded it to the unit. Here is the problem: whenever the the rover uses its motors at all, the unit completely shuts down. It then has to be switched off and on and rebooted. If it moves even the tiniest amount - the entire unit shuts down. It does not matter what the surface (carpet, wood flooring, asphalt) any attempt to move always causes an immediate shut down.

I saw the pinned banner about motor issues from a few years ago. We updated the firmware it is currently on:
cyberpi 44.01.011.

Any help would be greatly appreciated.

Thank you!
–Luke

#2

Just finished assembling Mbot2 Rover, having the same problem you are. Did you find a solution?

#3

Ok - slight clarification , the joysticks seem to have some involvement the pad on the controller doesn’t have the same problem. If I drive with joy stick it shutsdown, but with the control pad it’s not a problem.

#4

I haven’t found a solution, I assumed the control unit is receiving higher voltages or something from the motors then it is expecting and shutting down. This seems like something that could be corrected in the firmware.

I have only used the included blue tooth controller pad (looks like a video game console controller). You said yours was working if you used a different controller? Like the ipad app?

Thank you!

#5

@lavedon and @dtg123, when is the last time you charged the robot?

#6

@Rosco Immediately before using. Trying charging overnight as well. Its definitely charged. Thank you for the reply.

#7

@lavedon and @dtg123
What have you tried to control the device besides the app? You should try uploading a code manually as well, with different motor speed to see if power draw is the issue.

#8

I had a similar problem, and I found 2 issues that I consider to be design flaws.

The first issue is that the front wheel of each side of the rover goes into a threaded hole in the frame. The bronze bearing that gets inserted into the wheel is supposed to allow the wheel to run free without tightening or loosening the screw, but (for me) there was too much friction, and every time the wheel ran backwards it would tighten the screw until the wheel would freeze. I fixed this by moving the front wheel down a hole in the chassis to a hole that was not threaded, and I put a lock nut on the back of the screw to keep it in place.

After I did this, the rover would move a fraction and then stop. I found the problem to be that the wheels and tread were too tight and the motor(s) would stop from excessive power draw. I fixed this by moving the top wheel down a hole in the frame to make the tread looser. This fixed the problem, and the rover now moves as expected.

#9

THANK YOU!!! will try.

#10

Hi @lavedon

I’ve had problems with sticking wheels before ( on Ranger). You may find my two responses to this rather old post of some value:

https://forum.makeblock.com/t/how-to-make-auriga-turn-90-degrees-i-have-code/20836/7