adding extra sensors

Using Arduino Sensors
1

Hi
I'm using a line following and obstacle avoiding programme for a robot car, It works perfectly well, however, I would like to add two more ultra sonic sensors, plus the option of making it turn away from lines.
any help or advice would be more than welcome.

int vSpeed = 110;
int turn_speed = 230; // 0 - 255 max
int t_p_speed = 125;
int stop_distance = 12;
int turn_delay = 10;

//HC-SR04 Sensor connection
const int trigPin = 11;
const int echoPin = 12;

//L293 Connection
const int motorA1 = 3;
const int motorA2 = 4;
const int motorAspeed = 5;
const int motorB1 = 7;
const int motorB2 = 8;
const int motorBspeed =6;

//Sensor Connection
const int left_sensor_pin =9;
const int right_sensor_pin =10;

int turnspeed;
int left_sensor_state;
int right_sensor_state;

long duration;
int distance;

void setup() {
pinMode(motorA1, OUTPUT);
pinMode(motorA2, OUTPUT);
pinMode(motorB1, OUTPUT);
pinMode(motorB2, OUTPUT);

pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);

Serial.begin(9600);

delay(3000);

}

void loop() {
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distance= duration*0.034/2;
Serial.print("Distance: ");
Serial.println(distance);

left_sensor_state = digitalRead(left_sensor_pin);
right_sensor_state = digitalRead(right_sensor_pin);

//Dhaddammm Robotics//

if(right_sensor_state == HIGH && left_sensor_state == LOW)
{
Serial.println("turning right");

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,LOW);
digitalWrite(motorB2,HIGH);

analogWrite (motorAspeed, vSpeed);
analogWrite (motorBspeed, turn_speed);

}
if(right_sensor_state == LOW && left_sensor_state == HIGH)
{
Serial.println("turning left");

digitalWrite (motorA1,HIGH);
digitalWrite(motorA2,LOW);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

analogWrite (motorAspeed, turn_speed);
analogWrite (motorBspeed, vSpeed);

delay(turn_delay);
}

if(right_sensor_state == LOW && left_sensor_state == LOW)
{
Serial.println("going forward");

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

analogWrite (motorAspeed, vSpeed);
analogWrite (motorBspeed, vSpeed);

delay(turn_delay);

}

if(right_sensor_state == HIGH && left_sensor_state == HIGH)
{
Serial.println("stop");

analogWrite (motorAspeed, 0);
analogWrite (motorBspeed, 0);
while(true){

}
}

if(distance < stop_distance)
{

digitalWrite (motorA1,HIGH);
digitalWrite(motorA2,LOW);
digitalWrite (motorB1,LOW);
digitalWrite(motorB2,HIGH);
delay(250);
analogWrite (motorAspeed, 0);
analogWrite (motorBspeed, 0);
delay(500);
digitalWrite (motorA1,HIGH);
digitalWrite(motorA2,LOW);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

analogWrite (motorAspeed, t_p_speed);
analogWrite (motorBspeed, t_p_speed);
delay(900);

//Dhaddammm Robotics//

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

analogWrite (motorAspeed, t_p_speed);
analogWrite (motorBspeed, t_p_speed);
delay(800);

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,LOW);
digitalWrite(motorB2,HIGH);
delay(900);

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

delay(700);

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,LOW);
digitalWrite(motorB2,HIGH);
delay(650);

digitalWrite (motorA1,LOW);
digitalWrite(motorA2,HIGH);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);

left_sensor_state == HIGH;

while(left_sensor_state == LOW){

left_sensor_state = digitalRead(left_sensor_pin);
right_sensor_state = digitalRead(right_sensor_pin);
Serial.println("in the first while");

}

digitalWrite (motorA1,HIGH);
digitalWrite(motorA2,LOW);
digitalWrite (motorB1,LOW);
digitalWrite(motorB2,HIGH);
delay(100);

digitalWrite (motorA1,HIGH);
digitalWrite(motorA2,LOW);
digitalWrite (motorB1,HIGH);
digitalWrite(motorB2,LOW);
delay (500);

}
}

2

First, I would recommend to learn how to not use the delay function. Delay is a waste of processing cycles and stops your Arduino from doing something useful in between. When adding more functionality this is the number one issue.

Have a look at the following example

File -> Examples -> 02.Digital -> BlinkWithoutDelay

The next step would be to write some functions and structure your code a bit. This makes it easier for you and others to understand what is going on.

3

Can you please "learn how to use the forum - please read"...

Paste your code in code tags ( </> ) and Auto-format your code in the IDE using Ctrl + T...Thanks!

4

Read the how to use this forum-please read sticky to see how to properly post code. Remove useless white space and format the code with the IDE autoformat tool (crtl-t or Tools, Auto Format) before posting code.

Non-blocking timing tutorials:
Several things at a time.
Beginner's guide to millis().
Blink without delay().