Micropython Lesson 11

### Magicbit Servo

#### Introduction

A servomotor is an electrical device, which can push or rotate an object with great precision. If you want to rotate an object at some specific angles or distance, then you use a servo motor. It is just made up of a simple motor, which runs through servomechanism.

Learning outcome:

• Using servo motor with Magicbit

#### Theory

The servo motor works on the PWM (Pulse Width Modulation) principle, which means its angle of rotation, is controlled by the duration of the pulse applied to its control PIN. A servomotor is made up of a DC motor, which is controlled by a variable resistor (potentiometer), and some gears. Servomotors control position and speed very precisely. Now a potentiometer can sense the mechanical position of the shaft. Hence, it couples with the motor shaft through gears. The current position of the shaft is converted into an electrical signal by a potentiometer and is compared with the command input signal. In modern servomotors, electronic encoders or sensors sense the position of the shaft. A pulse of 1ms will move the shaft anticlockwise at -90 degrees, a pulse of 1.5ms will move the shaft to the neutral position that is 0 degrees and a pulse of 2ms will move the shaft clockwise at +90 degrees.

#### Code

from machine import Pin,PWM
import time
servo = PWM(Pin(26),freq=50)

while True:
servo.duty(180)
time.sleep_ms(500)
servo.duty(1)
time.sleep_ms(500)

Â