The electrical team really went all out this year to make things look good - but you wouldn't be able to see it if not for the nicely shaped and bended Plexiglass hood
Coincidentally, the charging/monitoring circuit we have on the OI is also in use on the electrical board on the robot. By using a few different components and different traces, they were able to use the same PCB in both locations - the one on the robot provides an 8-LED readout of the battery voltage (virtually identical to the read out on the OI), as well as a built in charging circuit for the backup battery. While you can always check the voltage from the OI (assuming it's tethered or in radio contact), having a quick glance circuit there really helps to know if you need to replace the battery or not, as you're looking right at it when you turn the robot on.