Arduino - Ultrasonic Sensor - Servo Motor

We will learn:

Hardware Required

1×Arduino UNO or Genuino UNO
1×USB 2.0 cable type A/B
1×Ultrasonic Sensor
1×Servo Motor
n×Jumper Wires
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About Servo Motor and Ultrasonic Sensor

If you do not know about servo motor and ultrasonic sensor (pinout, how it works, how to program ...), learn about them in the following tutorials:

Wiring Diagram

Arduino Ultrasonic Sensor Servo Motor Wiring Diagram

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Arduino Code - Ultrasonic Sensor Controls Servo Motor

/* * Created by * * This example code is in the public domain * * Tutorial page: */ #include <Servo.h> // constants won't change const int TRIG_PIN = 6; // Arduino pin connected to Ultrasonic Sensor's TRIG pin const int ECHO_PIN = 7; // Arduino pin connected to Ultrasonic Sensor's ECHO pin const int SERVO_PIN = 9; // Arduino pin connected to Servo Motor's pin const int DISTANCE_THRESHOLD = 50; // centimeters Servo servo; // create servo object to control a servo // variables will change: float duration_us, distance_cm; void setup() { Serial.begin (9600); // initialize serial port pinMode(TRIG_PIN, OUTPUT); // set arduino pin to output mode pinMode(ECHO_PIN, INPUT); // set arduino pin to input mode servo.attach(SERVO_PIN); // attaches the servo on pin 9 to the servo object servo.write(0); } void loop() { // generate 10-microsecond pulse to TRIG pin digitalWrite(TRIG_PIN, HIGH); delayMicroseconds(10); digitalWrite(TRIG_PIN, LOW); // measure duration of pulse from ECHO pin duration_us = pulseIn(ECHO_PIN, HIGH); // calculate the distance distance_cm = 0.017 * duration_us; if(distance_cm < DISTANCE_THRESHOLD) servo.write(90); // rotate servo motor to 90 degree else servo.write(0); // rotate servo motor to 0 degree // print the value to Serial Monitor Serial.print("distance: "); Serial.print(distance_cm); Serial.println(" cm"); delay(500); }

Quick Steps

  • Connect Arduino to PC via USB cable
  • Open Arduino IDE, select the right board and port
  • Copy the above code and open with Arduino IDE
  • Click Upload button on Arduino IDE to upload code to Arduino
  • Move your hand in front of sensor
  • See the change of servo motor

Video Tutorial

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Ultrasonic Sensor and Servo Motor on Commercial Products

  • Robotic Arm Kit for Arduino
  • Otto DIY Robot Builder Kit

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