AX-12A motor issues, Bioloid balance issues after installing new CM-530 controller

I got to installing the new CM-530 in a Bioloid GP type A humanoid setup. We had two nos of Bioloid GP (Humanoid type A) using AX-12A motors for a few years. One was not working due to one DXL port (of a CM-530) not working, and other had it’s controller (CM-510) stopped working. They were just kept away for almost two years.

I ordered new CM-530 controller units and installed in one of the robots.

I programmed the default type-A humanoid program (both tasks and motion) that comes with R+Task 2.0 and R+Motion 2.0 from my Window 10 PC.

Currently, the status is as follows:

For some reason it does not respond to sound (claps) so I modified the task file to respond to remote commands and set a sequence of moves to run one after the other:

  • Bravo
  • Chest beating
  • Scratch head
  • Pushup
  • Hand standing
  • Clapping
  • Ready (upright) position

I found that while doing ‘Bow’ move (motion index 1) it just falls on it’s face, so removed it.

Also, I noticed that the movements are a bit jittery and it shakes a lot.

I had set two other remote keys to execute ‘Left kick’ and ‘Right kick’, the left kick works fine (although occasionally the robot loses balance) but right kick never works correctly and the robot keeps falling to the right with foot in the air.

Another pair of commands ‘Block right’ and ‘Block left’ work but after they are executed it does not respond to any new commands.

So I have a few queries:

  1. If the Biolod robot (and it’s motors) are not used for a long time, do they have any problems?

  2. Sometimes I hear a sound like that of gear slipping from motors, especially the foot motors. It never happened earlier. Does this cause loss of calibration and/or accuracy of the motor?

  3. Some of the motions seem to run too fast, they can be slowed down a bit.

  4. Do we have any utility to check whether the AX-12A motor is functioning and calibrated correctly knows its position?

  5. I added a line to switch on gyro, but it does not seem to work that way.

  6. Are there any updated files (motion files in particular) that are more optimized and smoother on the motors, or have more accurate motions?

  7. In such case, do we need to replace any motors, although they are all detected correctly by the controller?

Thanks a lot!


  1. This depends on the storage conditions and other environmental or physical factors of the motors.
  2. This sounds like possible gear damage, and will certainly reduce accuracy. Continued use may also result in damage to the DC motor inside the servo.
  3. The Moving Speed control table item can be used to control actuation speed.
  4. DYNAMIXEL Wizard 2.0 Self Diagnosis can be used to test DYNAMIXEL function.
  5. Some information on Gyroscope usage is available on the component’s eManual page.
  6. R+ Task 3.0 features the latest available sample programs for all of our educational products.
  7. Replacing entire servos is most likely not needed. Given your issue description in point 2, replacing the gears may be enough to resolve the issue.