Register Battery Voltage with Ubuntu

I’m running my TX1 and some external hardware from a battery. The A/D conversion board I am using communicates its voltage to the TX1. The manufacturer has created a very basic driver that will update a text document with the voltage of the battery, along with some other data about motor electrical current draw (it also supplies power to a few motors). I would like to register the voltage value from this document as the OS battery level (after some calculations, of course) so that I can shut down gracefully before the battery dies. I have not been able to find a good way to do so. Is there a way to register this as a power device? Is there another accepted method that I could use?

Looks like you need a fuel gauge to manage the battery for TX1.