ROSbot XL (ASUS NUC)
Battery reached red low‑battery LED during operation
Robot was charged while ON
Upon connecting to charger, network was lost
Left the robot to charge for ~45 minutes
Turned it off
After this event, I hear pulses on power‑on
Pulsing occurs with spare battery (uncharged)
Pulsing occurs without ROS running
Robot loses network immediately after pulsing starts
In a few occasions, I manage to start the robot and move for ~ 1 metre, after that the pulsating sound and network loss.
Could it be the motor driver?
Attached audio/video for reference:
The robot in the video is shutting down after shutdown button was pressed.
Note: There are no other hardware drawing power from the battery at the moment, except for the LiDAR sensor. The cables you see on the video are not connected to the power board.
Thank you for the detailed description and for sharing the video. This looks like speaker audio being rapidly turned on and off. The behavior is broad may indicate many issues.
Was the robot charged using the original charger supplied with the robot?
From the symptoms you described (pulsing on power-on and immediate network loss), it is possible that there is a power instability. We recommend checking that:
No cables inside the robot are touching or shorting near the speaker or the DC-DC converter.
All internal cables are properly seated and not loose. Please especially check speaker cables and power cables inside the robot.
Please check that nothing is unintentionally contacting any PCB.
Could you also confirm what hardware was connected to the robot during operation before the issue appeared?
This will help us estimate the power consumption.
You mentioned that only the LiDAR sensor is currently connected, but it would be helpful to know what devices were connected previously as well as where in the robot each component was connected.
If possible, please describe how you detect “network loss”. Do you mean WiFi or Ethernet cable?
If you feel comfortable you can measure supply voltage for your NUC.
You can contact me direcrly on e-mail support@husarion.com to check if a warranty fix applies for your robot.
Indeed, when I checked the inside, a bolt and a washer were dislodged from the undercover landing on one of the boards. The problem is gone when I got rid of them. I was worried a bit.