Servomotors PDF Print


Servo motors are devices closed loop, ie, receive a control signal, there

the current position, operate the system going to the desired position.

In contrast to the solid motors that rotate indefinitely, the axis of

servo motors have the freedom of up to 180 degrees but are accurate as







These servo motors are divided into three basic components: actuator system,

sensor and control circuit.

Actuator system consists of an electric motor, in most cases with positive

DC, but also can find it AC.

Where this is also a set of gears forming a gear-box

with a very long relationship which helps to amplify the torque.


Sensor is usually a potentiometer attached to the shaft of the servant, with the value

its electrical resistance will determine the angular position of the shaft.


Circuit Control - The control circuit consists of electronic components

discrete or integrated circuits and generally consists of an oscillator and a

controller that receives a signal from the sensor (shaft position) and the control signal and

drives the motor in the direction needed to position the shaft in the desired position.


Servos have three wires interface, two for power and one for the signal

control. The signal control uses the modulation pulse width that has

three basic characteristics: minimum width, maximum width and repetition rate.


The pulse width control determines the position of the axis:

- Maximum width equal to the displacement of the axis of +45 in central position;

- Minimum width equal to the displacement of the axis 45 °;

- Other widths determine its position accordingly.


Now present a system that gives us this control by servo motor.

This system of radio frequency behaves in a simple and complete

basing their control functions by the transmitter to the receiver which in

time identifies the transmissions received and transports them to the servo motors.

Thus playing functionality in the system being controlled.


An equipment for the model airplanes to race cars is also

easy accessibility to other platforms.


As shown above the importance of using the servo motor, adapt

a system of a "parking gate" controlled by the transmitter, a servant

engine and airframe components MODELIX.


Look at what was needed for this adaptation:



Realizing the connections to the system:



We see in this picture the connection being made to

activation gate. With this connection made our system

control will be prepared to receive the signal to be

transmitted by the transmitter.


After an adjustment was made with the rod, because the notice

drilling that contains the shaft of the propeller is not compatible with the

standard MODELIX.




After adaptation to the adaptation of the hole with

hole had to be a diameter of 4mm.

Drill 4mm to redo the hole.






Once the adjustment of the propeller was made of the engagement

set of signal system with the structure MODELIX,

in the case created a barrier to generate the movements.


See video of this project here (click here to see video).        

This project presented is only one way of several other ways to

introduce a servo motor in a project MODELIX.

Awaken your creativity and introduce this system for their projects.


This kit was purchased on site for model aircraft Hobby Delivery and cost $ 185.00.

For more information visit now and get your System

Digital Radio Aggressor AM. In this store you will find several servo motors and other

electronics to develop new projects.



After the concept of functionality with the servo motor develops its functions, was

presented a barrier with two arms, the support arm and arm movement.


In this design adapted from one of the propellers of the radio frequency system drilling

compatible with standard MODELIX to more firmly in motion, and yet

not perform this operation, we can do it another way, tying a line

at both ends of the parties to generate the movement (propeller and arm support).

Note that the propeller shaft of the servo motor does not get an appropriate length, or

is, the transfer of movement would be very small, but to resolve this small

problem was added a long bar that pierced increased in length

significant and so we obtained a greater movement of the support arm, thereby generating

cycle of motion.


As explained at the outset the servo motor gets up to 180 ° degrees of motion

but this one has used freedom of 90 °. Therefore his movements will be

very limited. Enjoy this idea and create new ideas using these components.

The servo motors Aeromodelismo along with the radio transmitter was purchased in store Hobby Delivery company specializing in material Aeromodelismo. The Hobby Delivery has its flagship store in Vineyard SP, but it has some branches in other cities. Visit 

If you choose to build a circuit to control the servo motors instead of buying

the radio transmitter, there is much information available on the Internet that helps in understanding how

deal with this technology. See the links below:


New directions and new ideas are the strength of an open platform that develops

to develop.