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Unread 06-08-2013, 12:13
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AKA: Andrew Palardy (Most people call me Palardy)
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Re: pic: 3CIM Ball Shifter

Our driving theory around low (this was not always the case, but several of us on 33 have converged on this point independently) is that accelerating from a standstil is better in low gear, usually to around 60-80% of the low gear speed, than in high gear. So any time where we never reach peak speed in low, it's faster to drive in low. These are marginal gains in time. BUT, since high gear is in the 'bad side' of the motor power curve for the entire time (with 2:1 or more spread), the current draw from high gear will be WAY higher than in low. For the same or worse dynamic performance. This becomes MUCH worse on a dieing battery, which can frequently be seen near the end of a match.

We've sometimes run auto-upshift software to automate this, it begins the shift around 60% of low gear speed, but the shift takes time to execute under load (not sure exactly what speed it's at by the time the dog disengages).

We also run auton in low gear usually, for precision/control reasons, so a slightly high low gear is good for this. But we could run in high, we just don't, so it's not a huge objective.


I guess this differs from the 'west coast' opinion that 'high gear is where we operate, and low gear is just in case we need to push'. We operate in both gears.
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