LED Health Status

David was kind enough to set us up with a loaner Magni until ours is ready. When I left the office yesterday, I had 5 green LEDs, with the top one flashing intermittently, and the robot ran fine. Tonight, the bottom two LEDs are not illuminating and I cannot get the robot to drive.

In a private exchange with David he indicated that this sounds like a short on the auxiliary power supplies. I have not plugged anything into auxiliary power supplies.

One other thing: if I burn the latest image to an SD card and run the robot in AP mode, I get a blinking blue LED on the sensor bar. If I rename the hostname and take it out of AP mode, the blue LED no longer flashes. I am not sure what the flashing blue LED indicates (AP mode?).

Anything come to mind that I might check to resolve this?

I am running the latest (12-8) image.

Thanks,
Paul

On the LED that seem to not be functioning

  1. Check the voltage from the aux and main supplies to see if you are getting the appropriate voltage from them. If the LED are not lit then its most likely that the supplies are not running correctly.
  2. If they are not lit then systematically check for shorts. The power supply circuits have a short fault detector and shuts down the power supply when there is a fault.

On the blue light

  • The flashing blue light indicates the robot is in AP mode
  • When you rename it it stops blinking because its no longer in AP mode

Sounds like the batteries could be low. Check them with a multimeter, they should read above 22V.

Yes, the blinking blue led is for AP mode. When the robot connects to infrastructure wifi, the blue led stops flashing.

Rohan

The bottom led when on indicates 12V Aux is active.
The 2nd from bottom led is on when 12V Main is active.
Since the two supplies are independent but both run from a main 24 volt ish power from batteries the idea of the battery being low is highest on the list of possible issues.
The new rev in production has some improvements to make low battery sort of troubleshooting easier.

As was suggested, it was a low battery issue. Thanks for the help!

The ability to enter AP mode with a button push is a fantastic feature.
It makes working in a school environment one heck of a lot easier.
I wish you would add your pifi functionality to the Ubuntu and Raspbian
distros. It would make life a lot easier when working with Raspis.

Thanks again,
Paul

We have plans on improving the ability of indicating the batteries are too low in more obvious ways than have been done so allows us just a bit of time to continue to make this very basic issue much easier for a customer to detect and fix with charging cycle. Glad this was sorted out, Cheers.

Well - as of right now - as far as we know, we are the only ubuntu distro for the raspberry pi that still has an active maintainer. So come and get it!

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