Automatic Transmission

[Andrew Blair]

With DC motors, your shift down will, as a best reference, be decided by the current draw. If you exceed a certain current draw for a period of time, say 30 amps, you need to shift to a lower gear, should one be available. Vice-versa with the up-shift. If you are moving, and yet only pulling a few amps, you can safely up-shift. Most of your decisions about shift points will have to be determined by trial and error.

And, depending on your situation, you probably want to severely limit the opportunities for software to actually shift- otherwise you'll end up with alot of hunting, all the time. Sort of like an automatic going up a hill. Really, software should only shift if a relatively extreme limit has been passed- such as a quick jump in velocity for a field crossing, or a heavy spike in current draw during a pushing match.