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Unread 19-08-2014, 18:38
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Re: 2015 Beta Testing - The Components are Here.

The brown-outs also affect analog sensors like pots. What we saw during Alpha that we'll need to test again was this situation:

As we drew the battery down, then hit full throttle on the drivetrain (6 cim), it would drop the voltage to the potentiometer we used to measure position of our hi-lo. As a result, the hilo would begin to raise (closed loop control always commanding a position).

Of course, with the analog sensor the easy solution is to power it off the VRM. The only problem then is potential wind-up during the brown out period.

Of course, I'll point out that this was happening at very low voltages. We were seeing 6ish volts. We NEVER pull a battery that low during competition, and with the new current monitoring features in the PDB, we hope to monitor and control voltage and current as a safeguard against popping the main breaker as well.
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