Servo review
Servos: Purpose and Operating Principle
A servo is a device that includes a sensor for monitoring specific parameters. It also comprises the actuator itself, a control unit, and a parameter converter that provides the necessary output readings. For example, if the speed turns out to be too high, the servo can reduce it. The main task of the servo is to automatically correct parameters according to the set values.
Connecting the Servo
To connect the servo, it is necessary to use certain wires:
- black – ground;
- red – power;
- yellow – signal.
Types of Servos
There are two main categories of rotation servos: synchronous and asynchronous. Additionally, they are divided depending on their design features, for example:
- electromechanical servos;
- electro-hydromechanical servos.
Electromechanical servos use a gearbox and an electric motor, while electro-hydromechanical servos can create motion using a piston-cylinder system, allowing for higher speed.
Servos can be:
- with brushes;
- without brushes.
Brush-type models are represented by DC motors. They are also divided into digital and analog. Digital models are more modern and have control through special programs, which are sequentially transmitted via an interface. Servos can have either alternating or direct rotation.
Characteristics Features
One of the key parameters of servos specified in the documentation is the torque at the shaft, which determines the torque. Depending on the voltage, this parameter can have several values.
Another important characteristic of the servo motor is the rotation speed, which is indicated in a time parameter (for example, the output shaft must rotate 60 degrees).
Where Servos Are Used
Rotational motion servos are used in:
- equipment with numerical control (CNC);
- industrial robots;
- printing machines;
- industrial sewing equipment.
Moreover, they are applied in the field of instrument manufacturing and model aviation. Linear motion servos are used in the production of printed circuit boards and in magnet windings. Thanks to cutting-edge technologies, brushless servos are gaining popularity due to their higher efficiency as they do not have brushes and sliding contacts, ensuring greater power and torque.
Pros and Cons
Among the main advantages of servos, their versatility stands out. They can be used for devices of any power and type. Servos are quiet and provide higher movement speed than other types of motors. However, they require a sensor for operation, and the prices for such devices are usually higher. In some cases, stepper motors are used to save budget.