Maze Solver Servo Help!

Other Hardware Motors, Mechanics, Power and CNC
1

Hello Everyone!

I cant seem to get the left servo to work when the pololu QTR-8A sensors detect a line.

#include <Servo.h>

#define sensor1 A1
#define sensor2 A2
#define sensor3 A3
#define sensor4 A4
#define sensor5 A5
#define sensor6 A6
#define sensor7 A7
#define sensor8 A8
#define NUM_SENSORS 8

int blackLine = 600;
int whiteBoard = 400;

unsigned int sensor[8];

Servo leftServo;
Servo rightServo;

void setup(){
  Serial.print("Booting Up..");
  Serial.begin(9600);
  leftServo.attach(7);
  rightServo.attach(6);
  pinMode(sensor1, INPUT);
  pinMode(sensor2, INPUT);
  Serial.print(".");
  pinMode(sensor3, INPUT);
  pinMode(sensor4, INPUT);
  pinMode(sensor5, INPUT);
  pinMode(sensor6, INPUT);
  Serial.print(".");
  pinMode(sensor7, INPUT);
  pinMode(sensor8, INPUT);
  Serial.print(".");
  Serial.println();
  Serial.println("Booting Up Finished");
}

void loop(){
  
 sensor[1] = analogRead(sensor1);
 sensor[2] = analogRead(sensor2);
 sensor[3] = analogRead(sensor3);
 sensor[4] = analogRead(sensor4);
 sensor[5] = analogRead(sensor5);
 sensor[6] = analogRead(sensor6);
 sensor[7] = analogRead(sensor7);
 sensor[8] = analogRead(sensor8);
 
Serial.println(sensor[4]);
 if(sensor[4] >= blackLine){
  servo_forward(); // Move Forward    
 }
 
 
// Uncomment For Debugging!
/* for (unsigned char i = 1; i <= NUM_SENSORS; i++)
  {
    Serial.print(sensor[i]);
    Serial.print('\t'); // tab to format the raw data into columns in the Serial monitor
  }
  Serial.println();*/
  
  delay(250);
  
}

void servo_forward(){  //Servo Function
leftServo.write(180);
rightServo.write(0);
  
}

Thank You For Your Help!
Jordan

2

You only ever set the leftServo to one value, 180 degrees. Perhaps its already there?

BTW arrays are indexed from 0 upwards:

unsigned int sensor[8]; // sensor has 8 elements numbered 0..7
...
 sensor[8] = analogRead(sensor8);  // you've overwritten memory, fail...

Secondly why not put all your sensor pins in an array then you can
use a loop:

int [] sensor_pins = { A1, A2, A3, A4, A5, A6, A7, A8 } ;

...
  for (int i = 0 ; i < 8 ; i++)
    sensor[i] = analogRead (sensor_pins [i]) ;

If you're lucky and the analog pins are consecutively numbered you
don't even need the array of them (but check, different Arduinos are
different).

3

Thank You For Replying,

I have 2 continuous rotation servos and 180 should move it forward. When I plug the one that doesent move (the left one) into the right pin it moves. I will try the array for sensor pins.

--
Jordan