11-05-2017, 11:57 AM
Servomotors are very useful in electronics and embedded systems. You can find the use of the servo motor around it, they are used in toys, robots, computer CD tray, cars, plane, etc. The reason for this wide scope is that, servo motor is very reliable and accurate. We can rotate it to any particular angle. They are available in wide range, form high torque motor to low torque motors. In this tutorial we are going to connect a servo motor to the 8051 microcontroller (AT89S52).
First we have to understand the operating principle of the servo motors. The servo motor operates in PWM (main pulse width modulation), meaning that its angle of rotation is controlled by the pulse duration applied to its control PIN. Basically the servo motor is composed of a DC motor that is controlled by a variable resistor (potentiometer) and some gears. The high speed force of the DC motor is converted into the pair of gears. We know that WORK = FORCE X DISTANCE, in DC motor Force is lower and distance (speed) is high and in Servo, the force is High and the distance is less. The potentiometer is connected to the servo output shaft to calculate the angle and stop the DC motor at the required angle.
Servo motor can be rotated from 0 to 180 degrees, but can go up to 210 degrees, depending on the manufacturer. This degree of rotation can be controlled by applying a pulse of LOGIC level 1 for a duration between 1 ms and 2 ms. A 1 ms can rotate the servo to 0 degrees, 1.5ms can rotate to 90 degrees and the 2 ms pulse can rotate it to 180 degrees. Duration between 1 and 2 ms can rotate Servo motor at any angle between 0 and 180 degrees.
First we have to understand the operating principle of the servo motors. The servo motor operates in PWM (main pulse width modulation), meaning that its angle of rotation is controlled by the pulse duration applied to its control PIN. Basically the servo motor is composed of a DC motor that is controlled by a variable resistor (potentiometer) and some gears. The high speed force of the DC motor is converted into the pair of gears. We know that WORK = FORCE X DISTANCE, in DC motor Force is lower and distance (speed) is high and in Servo, the force is High and the distance is less. The potentiometer is connected to the servo output shaft to calculate the angle and stop the DC motor at the required angle.
Servo motor can be rotated from 0 to 180 degrees, but can go up to 210 degrees, depending on the manufacturer. This degree of rotation can be controlled by applying a pulse of LOGIC level 1 for a duration between 1 ms and 2 ms. A 1 ms can rotate the servo to 0 degrees, 1.5ms can rotate to 90 degrees and the 2 ms pulse can rotate it to 180 degrees. Duration between 1 and 2 ms can rotate Servo motor at any angle between 0 and 180 degrees.
Circuit Diagram
![[Image: 8051-servo-motro-circuit.gif]](https://circuitdigest.com/sites/default/files/circuitdiagram_mic/8051-servo-motro-circuit.gif)
