The RH4D/DH4D unit was built with robustness in mind at every step of the development process. User serviceability was also one of the main goals. This section details the most common issues and solutions for your unit.

One (or more) fingers aren't closing

You first need to check if the actuator that controls those fingers is not disabled by overload: check the LED; if it is blinking, check the pattern and colour to find out the error.
If there is an overload error, the best way to clear it is to power cycle the unit and ensure that you are not exceeding the unit's mechanical limits.
(it is also possible to clear overload errors by sending a Dynamixel RESET to the ID of the affected actuator or the rst console command)

Next, check if the tendon is broken. You can do this by pulling the base segment of the finger outwards to detach it from the hand. The finger is attached magnetically so the base should detach, assuming the finger is open.
If the finger and tendon separate completely from the hand, then the tendon broke and you need to replace it. You can find out how to do this in the Maintenance Instructions.
If the finger does not separate then you may have an issue with the motor. If this is the case the LED should be giving you a hint but in any case, get in touch with our Support Team.

When I send a command to move the fingers, they only start moving once I reach a certain threshold value for position

Your tendons are likely distended. While this is not a failure in itself, it can be caused by settling of the tendon fibers which are usually a result of usage with high forces. As long as you operate within the safety limits, there is no problem with this. To clear this offset/threshold, you can re adjust the tendons by following the Maintenance Instructions.

The movement of the Index fingers is not synchronized (there is an offset between them)

This is likely related to the above. However the index fingers are both actuated by one single motor. Each finger tendon must be adjusted individually on the pulley. Follow the same Maintenance Instructions as if one of the tendons had distended, and adjust it to match the other finger.

My robot [fell/jumped off a cliff/had a sky diving accident/...] and broke the Elbow attachment mechanism

The Elbow attachment mechanism is the means through which the hand attaches mechanically to your robot. It is designed with significant reinforcements to withstand as much as possible. In the unlikely event that it breaks, send a few pictures to our Support Team and we'll find the best way to get your unit back in top condition.

I have some other issue

Please get in touch with our Support Team at support@seedrobotics.com and we'll be more than happy to assist you. Pictures and detailed descriptions are most welcome :)

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  • dh4d/hardwaretroubleshooting.txt
  • Last modified: 2017/03/23 12:23
  • by wadmin