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DHB-10 ERROR - Motor or encoder error — Parallax Forums

DHB-10 ERROR - Motor or encoder error

coreywucoreywu Posts: 2
in Accessories
Hi,

I am encountering an error with the DHB-10 motor controller where the motors stop and the controller responds with an "ERROR - Motor or encoder error" when VERBOSE mode is on. I can reproduce this problem every time by sending GO commands for several minutes at high frequency (4 to 8 commands/second). To make the motors operate again, I turn everything off but the error always occurs after running for a few minutes.

Does anyone know what the issue is here? I have looked at the code for the DHB-10 firmware and it appears a MotorError occurs when the position controller cog stops running (when PDrunning < 1). From the code, it looks like this could be caused by either motor failing or a high offset without motor movement.

Thanks!

Comments

  • PublisonPublison Posts: 12,366
    coreywu wrote: »
    Hi,

    I am encountering an error with the DHB-10 motor controller where the motors stop and the controller responds with an "ERROR - Motor or encoder error" when VERBOSE mode is on. I can reproduce this problem every time by sending GO commands for several minutes at high frequency (4 to 8 commands/second). To make the motors operate again, I turn everything off but the error always occurs after running for a few minutes.

    Does anyone know what the issue is here? I have looked at the code for the DHB-10 firmware and it appears a MotorError occurs when the position controller cog stops running (when PDrunning < 1). From the code, it looks like this could be caused by either motor failing or a high offset without motor movement.

    Thanks!

    Welcome to the forums!
    Is this a new hardware build? It might be a mechanical issue with mounting the encoders.

    What is the power supply?


  • coreywucoreywu Posts: 2
    Hi Publison,

    I'm not sure what you mean by "new hardware build". I am using the Arlo kit with my own 12V, 8Ah power supply and stock DHB-10 firmware.

    I ran the Test Encoder Connections.bs2 test again and it shows motor encoder 1 having much fewer ticks than the other:

    Output:
    Testing...


ticksL = 35, ticksR = 190


ERROR: Motor 1 encoder
values out of range.
Recheck encoder connections
and assemblies.


Motor 2 encoder cables
are connected correctly.


Test done.

    Could this be related to the motor/encoder error I am seeing? The wheels appear to move at the same speed during the test, despite the encoder 1 ticks being low. I am running commands only using GO, so wouldn't the encoder measurements be unnecessary for me?

    I took apart the motor to look left encoder again and it appears that the one of the plastic parts of the sensor is fairly flexible. I am not sure whether it moves during operation, but it does seem like that could cause the number of ticks registered to be lower than expected?

    Pictures:
    http://i.imgur.com/ngz3Uaz.jpg
    http://i.imgur.com/XM6lNWE.jpg

    Thank you
  • PublisonPublison Posts: 12,366
    edited 2017-02-18 21:40
    coreywu wrote: »
    Hi Publison,

    I'm not sure what you mean by "new hardware build". I am using the Arlo kit with my own 12V, 8Ah power supply and stock DHB-10 firmware.

    I ran the Test Encoder Connections.bs2 test again and it shows motor encoder 1 having much fewer ticks than the other:

    Output:
    Testing...


ticksL = 35, ticksR = 190


ERROR: Motor 1 encoder
values out of range.
Recheck encoder connections
and assemblies.


Motor 2 encoder cables
are connected correctly.


Test done.

    Could this be related to the motor/encoder error I am seeing? The wheels appear to move at the same speed during the test, despite the encoder 1 ticks being low. I am running commands only using GO, so wouldn't the encoder measurements be unnecessary for me?

    I took apart the motor to look left encoder again and it appears that the one of the plastic parts of the sensor is fairly flexible. I am not sure whether it moves during operation, but it does seem like that could cause the number of ticks registered to be lower than expected?

    Pictures:
    http://i.imgur.com/ngz3Uaz.jpg
    http://i.imgur.com/XM6lNWE.jpg

    Thank you

    The mechanical issue I was referring to stems back to some Bot Bot problems. ie the encoder not place placed correctly, (ie slightly off axis).

    I don't own an Arlo kit, so it's going to hard for my to respond further.

  • VonSzarvasVonSzarvas Posts: 3,488
    Idea... Do you have the black plastic-like (delrin) toothed wheel which slides over the motor shaft to trigger the encoder sensor?

    Check there's no bits of material stuck in the teeth. Sometimes not all the delrin gets cleaned out after cutting. That will affect your count.
  • AlkarexAlkarex Posts: 30
    New related thread http://forums.parallax.com/discussion/167944/arlobot-dhb-10-motor-board-bug-with-encoders
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