DOC AI Cam updates: modem tweak, full SD cards

We have updated the software for the DOC AI Cam today. The main updates are:

• a tweak that may improve the modem communications
• a change so the camera behaves nicely when the SD card fills up

Modem tweak

We have seen a number of customers have had modems not working properly in the field. It is difficult to isolate exactly what is going on. It could be poor signal, incorrect configuration, or an incompatible data plan. However it could also be a problem with our software or hardware. The modems are tested during manufacturing.

We identified a possible situation when the modem is powering up at the same time as the Raspberry Pi the internal voltage may drop and potentially put the modem into an unexpected state. To counter this we've added a delay to the modem powering up. We don't know if this will fix the problems, but are curious to see if it helps.

Of course, if you have a camera whose modem is not working, it will not be able to update its software. To do this you'll need to connect your camera to a Wi-Fi network. This could be your phone's hotspot if you're in the field.

SD card filling up

Occasionally we have seen a camera be in the field long enough for it's SD card to fill up. Before today's change the camera would become very unresponsive when this happened and it would be difficult to get the recordings off the camera.  With this update the camera will stop recording with enough space to still function normally.

This situation will become more common if we have cameras operating for longer times on solar power without a high bandwidth connection. If we have the AI running on the camera and are sending information about which animals have been detected (over a low bandwidth network such as Celium), but not sending the videos, then the SD cards will fill up.

Note: if desired we could provide larger SD cards. This will need to be provided by us because the SD cards also contain the software to run the cameras.