Design

Algorithm

• Use the following code to set up the light sensor:

    from gpiozero import LightSensor, Buzzer
  
    ldr = LightSensor(4)  # alter if using a different pin   while True:
        print(ldr.value)
  

  Run this code, then cover the LDR with your hand and watch the value change. Try shining a strong light onto the LDR.

Raspberry/Python Code

from gpiozero import LightSensor, Buzzer

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(23,GPIO.OUT)
GPIO.setup(24,GPIO.OUT)
GPIO.setup(25,GPIO.OUT)
GPIO.setup(8,GPIO.OUT)

ldr = LightSensor(4)
ldr2 = LightSensor(17)
ldr3 = LightSensor(27)
ldr4 = LightSensor(22)

while True:

    bir=ldr.value+ldr2.value
    iki=ldr3.value+ldr4.value
    uc=ldr.value+ldr3.value 
    dort=ldr2.value+ldr4.value

    print("ldr= %s" %ldr.value)
    print("ldr2= %s" %ldr2.value)
    print("ldr3= %s" %ldr3.value)
    print("ldr4= %s" %ldr4.value)
    print("bir= %s" %bir)
    print("iki= %s" %iki)
    print("uc= %s" %uc)
    print("dort= %s" %dort)
    if bir>iki:
        GPIO.output(23,GPIO.HIGH)
        GPIO.output(25,GPIO.LOW)
        time.sleep(1)
    elif iki>bir:
     GPIO.output(25,GPIO.HIGH)
        GPIO.output(23,GPIO.LOW)
        time.sleep(1)
    if uc>dort:
     GPIO.output(24,GPIO.HIGH)
        GPIO.output(8,GPIO.LOW)
        time.sleep(1)
    elif dort>uc:
     GPIO.output(8,GPIO.HIGH)
        GPIO.output(24,GPIO.LOW)
        time.sleep(1)

Arduino Code 

#include <Servo.h>

Servo servo1;
Servo servo2;
int servo_position1 =0;
int servo_position2 =0;
int in_rasp1 =3;
int in_rasp2 =4;
int in_rasp3 =5;
int in_rasp4 =6;
int read1=0;
int read2=0;
int read3=0;
int read4=0;

void setup() 
{
  servo1.attach(9);
  servo1.write(90);
  servo2.attach(10);
  servo2.write(90);
  pinMode(in_rasp1, INPUT);
  pinMode(in_rasp2, INPUT);
  pinMode(in_rasp3, INPUT);
  pinMode(in_rasp4, INPUT);

}

void loop() 
{
  read1 =digitalRead(in_rasp1)
  read2 =digitalRead(in_rasp2)
  read3 =digitalRead(in_rasp3)
  read4 =digitalRead(in_rasp4)
  

  if (read1==HIGH)
  {
    for (servo_position =0 ; servo_positiion<=90; servo_position+=1)
    {
      servo1.write(servo_position);
      delay(10);
    }
  }
  else (read2==HIGH)
  { 
    for (servo_position =90 ; servo_positiion<=0; servo_position-=1)
    {
      servo1.write(servo_position);
      delay(10);
    }
   
   }
  if (read3==HIGH)
  {
    for (servo_position =0 ; servo_positiion<=90; servo_position+=1)
    {
      servo2.write(servo_position);
      delay(10);
    }
  }
  else (read4==HIGH)
  { 
    for (servo_position =90 ; servo_positiion<=0; servo_position-=1)
    {
      servo2.write(servo_position);
      delay(10);
    
   }

}