DC motors w/o gearbox for a robot?

Hi, I'm building a very small robot that uses (obviously) very small DC motors. There's no space for a gearbox to slow down the speed so I was thinking if is it possible to attach the wheels directly to the motors and then controlling them using PWM. What do you think? Has someone already tried this?

rickharris4 years ago
This is the only way I know of without using a gear box.

However MANY small robots do exactly that - use a small gear box to reduce speed and increase torque.
robot.jpg
You're going to need very small gearboxes. You can't drive directlym, because there isn't enought torque from the motor at low speeds..

You MIGHT get away with driiving rubber wheels with the motor shaft, giving you a high reduction, without gears.