I would like to build a small two-wheeled robot similar to the one shown here.
In order to keep the robot small, I intend to use two coreless micro motors like the one shown bellow. The power source would be 2 AAA or AA batteries, in order to reach 3 V. These batteries would represent the bulk of the weight of the robot. The rest of the robot would be virtually weightless.
The specifications of one of such motor are:
Motor diameter: 6 mm Motor length: 12 mm Output shaft: 0.8 mm Output shaft length: 4 mm Voltage: 3 V Current: 17 mA (stall 120 mA) Frequency: 22000 RPM
My question is if small DC motors of this type have enough torque to even make the robot start moving. I have been unable to find torque info on these kind of motors and I suspect the weight of the robot could be too much for them to handle. Do you know the typical torque of such motor? Is there another type of (cheap) motor more appropriate for this project?