SIM/CIM motors with gearboxes in revolutions per second

[Joshamuffin]

I've seen both SIM and CIM. I'm not sure which spelling is correct.

But how fast can they move in revolutions per second with the gear boxes? I need to know the maximum speed the wheels can move.

I also need to know how many revolutions per second without gear boxes.

[AndyB]

It completely depends on which wheels (assuming rover wheels here), gearboxes, sprockets you are using.

And it is CIM for the record.

[Tristan Lall]

Originally Posted by Joshamuffin

I've seen both SIM and CIM. I'm not sure which spelling is correct.

CIM is correct, from Chiaphua Industrial Motors, or sometimes, CCL Industrial Motors. (CCL stands for Chiaphua Components Limited.)

Originally Posted by Joshamuffin

But how fast can they move in revolutions per second with the gear boxes. I need to know the maximum speed the wheels can move.

The free (unloaded) speed of the FR801-001 motor at 12 V is 5 310 rev/min (or for the pre-2005 models, either 5 600 rev/min or 5 342 rev/min, depending on which specification sheet you consult). These speeds should be regarded as approximate, because the output power of a motor will often vary a bit.

To know the maximum speed of the wheels, you need describe the gearbox. What is its ratio? (how many turns of the input equal one turn of the output?)

For the AndyMark Toughbox that came in the kit, the ratio is 12.75:1, so in theory, the wheels should spin at 416.5 rev/min.

If you're using the rover wheels (and you'd better be, if you're running this on the playing field), the diameter is Ø6.08 in*. That means that your robot's maximum speed is given by the perimeter of the wheel (i.e. one revolution) times the rotational speed of the wheel, converted to appropriate units. This comes out to a theoretical top speed of 11.0 ft/s.

*As of about a week or two ago, the drawing on AndyMark's website indicated the diameter as Ø6.125 in, which is the diameter before the plastic shrinks in the mould. The CAD model indicated a diameter of slightly less than Ø6 in, which was not correct.

[Joshamuffin]

I meant the AndyMark Toughbox from the kit.

Thanks for your help! I may now proceed with my equations and stuff.