Servo engine
The servo motor has become the basic element when it comes to mounting any electronic circuit in which an electric motor is required. The servo motor combines a mechanical part with a digital part. The latter is able to better process the signal and offer better results in any servo application.
When the first machines were invented, based on the steam technology developed by James Watt, they offered considerable simplicity. Today, however, the movement of motors, shafts, and other motor parts requires considerable control. Something essential, since in many of its applications not only the turning of the axes matters, but also their rhythm and the way in which said displacement is carried out.
For this reason, it is usual that today we find all kinds of servomotors in our environment. Unlike the motors managed by digital converters, the servos have a greater control capacity, better manage the speed of rotation and allow the position in which the axis rotates to be controlled at all times. Something fundamental for those machines in which the rotation and position of said axis changes what the machine is doing, as can happen in a cutter or in a robot.
Although servo motors are typically used in industrial applications, they can also be used for small DIY tasks and other simple assemblies, such as those that can be run with an Arduino servo motor. Something that shows that these servomotors are just as scalable as conventional motors. Therefore, we are going to analyze what this device consists of, to give you all the information you need to handle it.
what is a servo motor
A servo motor, also called servo or servo motor, is a drive device that is responsible for starting, stopping and regulating movement in all kinds of electromechanical projects. Inside it is an encoder, which is the key to its success. This element has the ability to convert the mechanical movement of the motor and the turns it makes into digital pulses. These pulses are interpreted by a motion controller, which generates a clearer signal and a better understanding of what is happening at any given moment.
On the other hand, the servomotor incorporates a driver or wheel, with which it is possible to control both the position and the torque of the motor and the speed at which the motor shaft rotates. A complete approach that offers greater efficiency than other similar elements, such as frequency converters. In addition, servo motors work in all types of devices and speeds , while converters are not always suitable in circuits with a low speed of movement or displacement.
How does a servo motor work?
Once we have the structure and the elements that are part of the servomotor, it is time to know how it works. The first thing we find in the servo motor approach is a pulse width to voltage converter. This is responsible for receiving the energy and converting it from pulses to volts, thus improving control.
On the other hand, we also find a mechanical coupling and a motor system, with which the movement will be generated. This element is accompanied by a potentiometer, connected to the central axis of the motor and which allows knowing the angle at which its axis is located. Something fundamental in applications in which the position matters, as it happens in certain complex machines. In fact, the industrial servomotor is a great solution to gain control and precision.
Both the potentiometer and the converter generate a signal that goes to the comparator. In this element, the entire operation of the device is controlled and it is verified that it performs as it should, taking into account aspects such as the angle of the axis, the speed of rotation or the power established by the operator. These elements are connected to the control panel of the servomotor, which is where we will control the speed of operation of the device .
This signal travels to the motor and restarts the process again, if there is a variation, or maintains the monitoring of the system, if there has been no change. This is the key to the servomotor and its operation: to always keep the movement and the input voltage controlled and consistent through a high-efficiency digital system.
For the control of the servo motor, so-called pulses are used. At each pulse that occurs, the motor axis reproduces a specific movement and changes position, according to the configuration that we have established. These pulses are also adjustable, so that the motor has a higher or lower speed. All this process is carried out by means of an electronic board, which makes it easy for the operator to establish the pulses and work rhythms that he may need.
Types of servo motors
To close our article, we are going to get to know some of the most common servomotors on the market. All of them come in different sizes, powers and capacities, so whether you are looking for small Arduino servomotors or if you need large and powerful models, you can find them in the types that we discuss below.
DC servomotor: These servomotors are the most common. They work with direct current and are managed by means of a pulse width modulation system, which follows the pattern of steps that we have commented on previously.
Alternating current servomotor: Its approach is similar to the direct current ones, although in this case the power supply changes. Since alternating current can be more powerful than direct current, these models are used to move heavier loads or for tasks that require more driving force.
Permanent magnet servomotor: These servos change their basic operation, eliminating the usual brushes in alternating current motors. That is why they are called brushless. Their approach is based on synchronous motors and they are capable of supporting high powers and speeds. Therefore, they are the most common in industrial applications.
Step-by-step servomotor: This device does not follow the full rotation approach of a conventional motor, but each pulse generates a step, a certain variable rotation angle according to the configuration established by the operator. They are the most interesting for tasks that require high precision and exact control of movement.
