Introduction: How to Make an Obstacle Detecting Car

By

this is a car

Step 1: Getting Materials

you will need

  • abra electronics geeekus gk kit 003 ($74)
  • 2 non polarized capacitors ($8)
  • h bridge($7)
  • 2 electric motors ($8)
  • arduino uno ($23)
  • distance sensor ($8)
  • wires($15)
  • breadboard ($10)

Step 2: Assemble the Car

attach the arduino to the top of the car with screws and attach a small breadboard to the other side of the car

put the motors into the mounts and solder wires to the end of the motor terminals

Step 3: Wiring

follow this circuit except wire trig on the distance sensor to pin 8 and wire echo to pin 7

Step 4: Coding Part 1

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// for distance sensor

const int trig = 8;

const int echo = 7;

int duration = 0;

int inches = 0;

// for right motor const int controlPin1 = 5;

const int controlPin2 = 2;

const int enablePin1 = 9;

// for left motor const int controlPin3 = 3;

const int controlPin4 = 4;

const int enablePin2 = 11;

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this goes before the void setup and sets up the pins

Step 5: Coding Part 2

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void setup() {

Serial.begin(9600);

// for distance sensor

pinMode(trig,OUTPUT);

pinMode(echo, INPUT);

// for right motor

pinMode(controlPin1, OUTPUT);

pinMode(controlPin2, OUTPUT);

pinMode(enablePin1, OUTPUT); //turn the motor off, initially

digitalWrite(enablePin1, LOW);

// for left motor

pinMode(controlPin3, OUTPUT);

pinMode(controlPin4, OUTPUT);

pinMode(enablePin2, OUTPUT); //turn the motor off, initially

digitalWrite(enablePin2, LOW); }

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this sets up the h bridge and the distance sensor

Step 6: Coding Part 3

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void loop() {

// for distance sensor

digitalWrite(trig,LOW);

delay(0.001);

digitalWrite(trig,HIGH);

delay (0.01);

digitalWrite(trig, LOW);

duration = pulseIn(echo,HIGH);

inches = duration /74/2;

Serial.print("inches: ");

Serial.print(inches);

Serial.print("");

Serial.println();

delay (5);

if (inches <5){

analogWrite (enablePin1, 200);

digitalWrite (controlPin1, LOW);

digitalWrite (controlPin2, HIGH);

analogWrite (enablePin2, 200);

digitalWrite (controlPin3, LOW);

digitalWrite (controlPin4, HIGH); }

else if (inches >=5 and inches <9 ){

digitalWrite (controlPin1, LOW);

digitalWrite (controlPin2, LOW);

analogWrite (enablePin1, 0);

digitalWrite (controlPin3, LOW);

digitalWrite (controlPin4, LOW);

analogWrite (enablePin2, 0); }

else if (inches >=9){

analogWrite (enablePin1, 255);

digitalWrite (controlPin1, HIGH);

digitalWrite (controlPin2, LOW);

analogWrite (enablePin2, 255);

digitalWrite (controlPin3, HIGH);

digitalWrite (controlPin4, LOW); }

}

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this makes it so that the car stops between 5 and 9 inches, move backwards between 0 and 5 inches, and moves forwards from 9 inches to infinity