Electric motors have become more diverse and adaptable than ever before. The choice of motor is extremely important when planning a motion control system. The motor needs to align with the purpose and overall performance goals of the system. Fortunately, there is a motor design suitable for any purpose imaginable. Some of the most common electric motors that are used today include:
AC brushless motors – AC brushless motors are some of the most used when it comes to motion control. These motors use induction of a rotating magnetic field, generated in the stator, in order to turn the stator as well as the rotor at a synchronous rate. The motors rely on permanent electromagnets to operate.
DC brushed motors – In this type of motor, brush orientation on the stator determines current flow. In certain models, the brush’s orientation relative to the rotor bar segments is decisive instead. The commutator is very important in a DC brushed motor design.
DC brushless motors – The DC brushless motors were developed to achieve a higher performance in a smaller space than the DC brushed motors, they are also smaller than comparable AC models. An embedded controller is used in order to facilitate operation in the absence of a slip ring commutator.
Direct drive – The direct drive is a low-wear, high-efficiency technology implementation that replaces conventional servo motors as well as their accompanying transmissions. Apart from being much easier to maintain over a long period of time, these types of motors accelerate faster.
Linear motors – These types of electric motors feature an unrolled stator and motor, producing linear force along the device’s length. Contrary to cylindrical models, the have a flat active section featuring two ends. They are normally faster and more accurate than rotary motors.
Servo motors – A servo motor refers to any motor that is coupled with a feedback sensor to facilitate positioning, therefore, these motors are the backbone of robotics. Both linear and rotary actuators are used. Cheaper brushed DC motors are very common, however, they are being superseded by brushless AC motors for high-performance applications.
Stepper motors – These types of motors use an internal rotor, which is electronically manipulated by external magnets. The rotor can also be made with permanent magnets or with a soft metal. As windings are energized, the rotor teeth align with the magnetic field, this then allows them to move from point A to point B in fixed increments. Before any work can begin on a new system, you should think very carefully about the competing properties of the different motors. Any project will be off to a better start with the right motor.