Automatic Transmission

[DonRotolo]

Current can be measured in many ways. PWM value only relates to voltage, not current. One way to measure current is to detect the magnetic field surrounding a current-carrying wire. Another way is to measure the voltage drop across a very low-value resistor (specially built to handle the current). Do some research on that.

As to figuring out trial and error, drive the robot in high gear and see at what motor current it starts to lose pushing power. That's where you shift to low. Then drive in low and see where you're coming close to top speed - that's where you shift to high.

For example. Again, this is not wild cutting-edge technology, there's a lot on the web if you take a look.

Don

[Andrew Blair]

As far as letting the motor coast between shifts- I really don't know, but we intend to find out! We're using Dewalt 3-speeds this year, so we may implement an auto-shifter if we have time and motivation. With respect only to the Dewalt, as a fully assembled drill, it does seem to shift smoother more regularly if you let off a bit. However, if you hit it right, even with the trigger mashed, it still will shift smoothly on the fly. Sometimes. As far as a dog or ball shifter, because the shift is one stage into the gearbox, I think you typically just shove it. Not sure on that though, so a second opinion will be a good idea...