light tracking using continuous servo

Projects General Guidance
1

Hi,

I am currently doing a project. I used an array of LDR sensors (8 of them), installed them stationary around the lightcrafter. These LDRs are use for a wake-up system, if they sensed any strong light, it will trigger the relay and turn on the lightcrafter.

On the rotating platform, there will be another 3 LDR sensors to track the light source. Please find the attached code and image below to have better understanding what I am doing

I have tried out my code but it seems to have some problems.
Can anyone help me with that? I believe is my coding problem.

relay i using - http://www.sgbotic.com/index.php?dispatch=products.view&product_id=1717

motor i using - http://www.01mechatronics.com/sites/default/files/docs/SuperModified.V3.Datasheet.pdf

circuit diagram

how i install those LDR

#include <ZerooneSupermodified.h>
#include <Wire.h>

ZerooneSupermodified motor(ZO_HW_WIRE);

int sens1 = A0;              // LDR 1 pin
int sens2 = A1;              // LDR 2 pin
int sens3 = A2;              // LDR 3 pin

int array1 = A3;             // LDR pins for wake up 
int array2 = A4;
int array3 = A5;
int array4 = A6;
int array5 = A7;
int array6 = A8;
int array7 = A9;
int array8 = A10;

int relay = 7;               // relay pin 
int tol = 40;                // tol difference
int pos = 0;                 // initial position
 
void setup() 
{ 
  pinMode(relay,OUTPUT);             
}  
 
void loop() 
{ 
  int val1 = analogRead(sens1);        
  int val2 = analogRead(sens2);        
  int val3 = analogRead(sens3);        
  
  int val4 = analogRead(array1);
  int val5 = analogRead(array2);
  int val6 = analogRead(array3);
  int val7 = analogRead(array4);
  int val8 = analogRead(array5);
  int val9 = analogRead(array6);
  int val10 = analogRead(array7);
  int val11 = analogRead(array8);
 
  int diff1 = abs(val1-val2);
  int diff2 = abs(val3-val2);
  int diff3 = abs(val1-val3);
  
  int avgT = (val4 + val5 + val6 + val7 + val8 + val9 + val10 + val11)/8;            
  if(avgT < 400){                                             // when the LDRs sense strong light 
    digitalWrite(relay,HIGH);                                 // turn on the relay
    if((diff3 > tol)||(diff3 < -1*tol)){                      // check the left and right LDR difference
      motor.start(4);                                         
      if(!motor.getCommunicationSuccess()){
        motor.resetErrors(4);
      }
      if(val1 < val3){                  // smaller value means stronger light
        pos = pos + 91;                 // 91 ticks mean 1 degree
      }
      if(val3 < val1){
        pos = pos - 91;
      }
      if((diff1 < -1*tol)&&(diff2 < -1*tol)){    
        if((val2 < val1)&&(val2 < val3)){           // if the middle one senses strongest light than the other two, stop the motor
          motor.halt(4);
        }
      }
      motor.moveToRelativePosition (4,pos);         // move the motor
      delay(50);
    } 
  }
  else{
    digitalWrite(relay,LOW);                       // if no strong light sense, off the relay 
    motor.stop(4);                                 // stop the motor, cut off communications
    pos = 0;                                       // initialize the position
  }
}
2

Are the LDRs and divider Rs calibrated or matched for output? If not, you will get different values for same light level and therefore false directions.

Weedpharma

3

maybe edit your first post and add ZerooneSupermodified to the subject line ? this is not a common library, for me. so you may need someone with experience to help with that.

4

weedpharma:
Are the LDRs and divider Rs calibrated or matched for output? If not, you will get different values for same light level and therefore false directions.

Weedpharma

I have record down all the readings of LDR and match them for the output already. But the motor still go haywire and spinning left or right all the way

5

dave-in-nj:
maybe edit your first post and add ZerooneSupermodified to the subject line ? this is not a common library, for me. so you may need someone with experience to help with that.

Hi,

I don't really get your meaning, do you mind showing me some examples or what?
Like which part I should shift around