This handout will give you information on some basic principles when choosing what motor to use for what application in your machine. The acceleration is very short and therefore can be ignored here. Torque Return to top of Page Figure above shows the basic torque equation as a function of force, angle, and radius. The units of torque are Nm or ft-lbs. In our steady state model of motors there are two parameters that we are interested in.
Units are ft-lbs.
The rotational speed of the motor shaft when there is NO torque being applied to it. For this model of an electric motor the torque speed curve is linear. The plot below is for the Bosch Motor. The Bosch motors have a no load speed of 95 RPM and a stall Torque of 0.6 Nm. Thus if we know the torque applied to the motor shaft we can find how fast the motor will rotate.