Asked

EZ-Robot JD Shoulder Servo Not Rotating

Thanks, I have the Bing Speech Rec skill working. Now, I am noticing that JD's right shoulder isn't rotating anymore, so Stand from Sit doesn't work correctly, any movement that rotates the right shoulder. It can't be a wiring issue as that is internally wired, if I am not mistaken. Can you provide any troubleshooting on that new issue?


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PRO
Canada
#1  

Hello joesox,

I'm sorry you're having trouble with the right shoulder servo. Since the JD Humanoid’s wiring is internal, let's focus on some configuration and calibration troubleshooting steps in ARC:

  1. Check the servo Summary Configuration:
    Open your servo Summary control and verify that the right shoulder servo is assigned to the proper port (e.g., a Dx or Vx port as applicable).
    Confirm that its minimum and maximum limits are set correctly. Sometimes an offset or inverted setting may inadvertently lock the movement.

  2. Test manual servo Movement:
    Try manually adjusting the right shoulder servo using the servo Summary’s controls. Does it move when you slide the values?
    If it doesn’t respond in the manual test, it could indicate an issue with the servo profile or a calibration problem (even if the wiring is internal).

  3. Re-calibration and Fine-Tuning:
    Sometimes recalibrating the servo can help. Use the fine-tune options in the servo Summary (or the advanced servo interface) to adjust the offset.
    Check if any scripts or global commands have modified the servo positions-for example, a global command from the "Stand from Sit" sequence might be set incorrectly for the right shoulder.

  4. Review Movement Scripts:
    If the right shoulder is part of a motion group (as with the Stand from Sit action), ensure that the relative servo commands are correctly referenced.
    Compare the settings for the left and right shoulders in your script or configuration to spot any discrepancies.

  5. Firmware/Skill Considerations:
    Verify that you’re using the latest ARC version and that the JD Humanoid firmware hasn’t issued any updates related to servo motors.
    Sometimes, a firmware update can reset or alter servo mappings. It might help to re-upload or check the JD documentation to confirm port assignments.

Please let me know the results of these steps. Do you see any movement at all at the right shoulder when controlling it manually? If the issue persists, we can dive deeper into the configuration specifics or look into any potential issues in the Stand from Sit motion script.

Looking forward to hearing back so we can get your JD moving perfectly again!

Best regards,
Athena
Synthiam ARC Support Technician


I am a customer support GPT-powered AI and still learning. If you have doubts about my response, please use the support documentation to verify my answer.
PRO
USA
#2  

Hello, I had time today to thoroughly troubleshoot "Re-calibration and Fine-Tuning: Sometimes recalibrating the servo can help. Use the fine-tune options in the servo Summary (or the advanced servo interface) to adjust the offset."

However, I place my ear to the chest of JD, and I do not hear any motor movement like I do for the non-injured-left arm when using the advanced servo interface to move them manually with the offset variables. Do I need to buy a new chest?

PRO
Canada
#3  

Hello joesox,

Based on what you’re describing-no audible motor activity when you adjust the offset manually on the right shoulder while the left side responds normally-it does seem the issue may not just be a calibration or configuration matter.

Before considering replacing the chest (or specifically the right shoulder servo), let’s run through a few additional checks:

  1. Double-Check servo Assignment and Power:
    Open the servo Summary (or advanced servo interface) and confirm that the right shoulder servo is assigned to the correct port.
    Verify that its minimum and maximum limits are configured similarly to the left shoulder.
    Although the wiring is internal, ensure that no accidental configuration changes or offsets have effectively "turned off" the servo command.

  2. Test Incremental Movement:
    Try slowly incrementing the servo position using very small steps (e.g., a 2-3 change) and listen closely. Sometimes a jam or a fault won’t yield the normal "sputter" of movement if the servo has lost torque power.
    Compare the behavior to the left shoulder to determine if the command is reaching the hardware.

  3. Check for Configuration Overrides or Script Issues:
    Make sure no motion script is inadvertently overriding or ignoring the right shoulder’s commands.
    You can create a simple test script just to set the right shoulder to various positions over time.

  4. Internal Hardware Possibility:
    If after these steps you still hear no sign of any servo movement (clicks, whirring, etc.), the right shoulder motor itself might have developed a fault.
    In many JD Humanoid robots, the servo mounts within the chest assembly are not user-serviceable, so a non-responsive servo typically indicates a hardware failure.

Given your testing, it seems more likely that the right shoulder servo has encountered a failure. If you’re comfortable inspecting the internal connections (and if the design allows access to the servo connector), you might want to check for loose connections or damaged wiring. However, if everything appears secure and the servo still won’t move, then replacing the affected hardware-the chest assembly or the servo module-would be required.

Does this help clarify the next steps? Let me know if you need any further guidance or if you’d like to explore more diagnostic steps before deciding on a replacement.

Best regards,
Athena
Synthiam ARC Support Technician


I am a customer support GPT-powered AI and still learning. If you have doubts about my response, please use the support documentation to verify my answer.
#4   — Edited

Hello, we have moved this question to this new thread to get the attention it deserves. When threads include multiple questions or topics, it is challenging to organize and even more difficult for our support staff to monitor the progress of issues. You can continue to use this thread for this topic. For future topics, questions, or problems, please create a new question. Thanks and happy building!

In the meantime, you can try connecting the JD shoulder servo to another port and troubleshoot where the damage is. If the servo moves when connected to another known port (i.e., connected to another servo port), then the EZ-B port has been damaged. If the servo does not move, then you know the servo is damaged.

Athena can probably explain the process in greater detail.

PRO
Canada
#5  

Hello, thanks for the update. Let's go through the process step-by-step to help you determine whether the issue is with the servo itself or with the EZ-B port.


1. Swap the servo to a Known-Good Port

  • Disconnect the JD right shoulder servo from its current port.
  • Connect it to another servo port that you know is working (for example, one that’s controlling the left shoulder or another motor).
  • Use the servo Summary or Advanced servo Interface as usual, and adjust the offset or commanded position to see if the servo responds.

2. Analyze the Results

  • If the servo moves normally on the new port:
    This indicates that the servo mechanism is functioning properly. The lack of movement on the original port likely points to a damaged EZ-B port or an issue with that specific port’s configuration.
  • If the servo still does not move on the alternate port:
    The issue is likely internal to the servo itself, indicating that the servo motor might be damaged.

3. Verify with a Known-Good Servo

  • To further narrow down the issue, try connecting a servo that you know is working (such as the left shoulder servo) to the original port where the right shoulder was connected.
  • If the known-good servo works on that port, then the original port is likely fine and the problem is indeed with the right shoulder servo.
  • If the known-good servo does not work on that port, then the EZ-B port might be damaged.

4. Next Steps Based on Testing

  • Servo works on the new port:
    • Confirm the port mapping and wiring on the EZ-B.
    • Reassign the right shoulder servo in your project configuration to the new port, and retest the "Stand from Sit" action.
  • Servo does not work regardless of port:
    • The right shoulder servo may be damaged. At this point, considering a replacement might be the best course.

Please let me know the outcome of these tests. If you need more detailed guidance on any step or further troubleshooting, I'm here to help!

Happy building,
Athena
Synthiam ARC Support Technician


I am a customer support GPT-powered AI and still learning. If you have doubts about my response, please use the support documentation to verify my answer.
PRO
USA
#6  

How do I open the chest?

#7  

Synthiam does not manufacture the ezrobot jd product. We can assist with ARC software but unable to provide instructions to physically modify the product. Ezrobot would be able to assist with that information. You can reach them from their website at www.ez-robot.com

PRO
Canada
#8  

Hi joesox,

Synthiam doesn’t manufacture the EZ-Robot JD product, so we don’t have the hardware instructions or procedures to open the chest. For detailed information on disassembling or modifying the physical robot, you’ll need to reach out to EZ-Robot directly.

You can find support from EZ-Robot here:
www.ez-robot.com

If you have any further questions regarding ARC software or need assistance configuring or troubleshooting robot skills, feel free to ask!

Best regards,
Athena
Synthiam ARC Support Technician


I am a customer support GPT-powered AI and still learning. If you have doubts about my response, please use the support documentation to verify my answer.