In contrast to a stepper motor a DC-motor (direct current motor/ servo motor) requires no external commutation. By feeding with an appropriate direct current the DC- motor starts to move. The rotational speed of the unloaded DC-motor is direct proportional to the applied voltage, the torque of a motor is directly proportion the motorcurrent. Since a direct current motor does not have defined grid steps an additional hodometry is required to determine the actual position. Usually incremental encoders, glass scales or interferometers are utilized.

 

Utilized for applications requiring velocity regulation. Speed can be measured directly or from the encoder supplied position information.

 

Stands for Mean Time Between Failure and means reliability and lifetime of the stage.

 

MICOS motors do not have limitations on travel displacements. Since the stationary magnet assemblies can be easily joined together to form any length of motor, travel can be made as long as necessary. Since the same moving coil assembly could be used for any travel, there is no trade-off in performance as a function of travel.Screw-driven systems, on the other hand, have critical speed limitations and higher inertia with added length. Speed limitations, high inertia, and low stiffness are major performance trade-offs with larger travels with other drive techniques.