[Jared]

I've attached an excel spreadsheet with a few of the motion equations I've come up with so far. For inputs, they take motor constants. If you have a gear reduction before the motor constants, you need to come up with a new set of motor constants that match the characteristics of the output of the gearbox.

The first sheet is for some mechanism which is always fighting gravity in the same direction it is trying to move. The speed under load after a few seconds matches the loaded speed values calculated by the JVN design calculator.

The velocity is determined exactly, not by numerical integration. I don't know how to integrate that velocity function (though I'm sure it's possible), so I did what you suggested in your previous post.

The second sheet calculates velocity and position with explicit functions for each, but does not take into account gravity. The velocity function had a less complicated integral. This would work for a drive system, but not for an elevator. I like this better because the robot could simply plug in the time elapsed into the position function to determine its setpoint.

If you're interested in seeing my work, I could take a picture of it.


Our 2015 elevator has these values
stall torque 25 nm
mass 35 kg
free speed 32 rad/sec
sprocket radius .022 meters

It's way overpowered, and does achieve full speed in less than .25 seconds under load.