Answers for "solar tracker with photoresistance"

solar tracker with photoresistance

int motorCW = 5;
int motorCCW = 6;
int enable = 8;
int lightCCW = 12;
int lightCW = 13;
int mode = 0;

void setup() {
  // put your setup code here, to run once:
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(8, OUTPUT);
pinMode(12, OUTPUT);
pinMode(13, OUTPUT);
attachInterrupt(INT0 ,modeChange, RISING);
Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
float voltage1, voltage2, comp, angle;

// Retrieve the voltage readings from the light sensors.
voltage1 = getVoltage(0);
voltage2 = getVoltage(1) - 0.09;

// Prints the current mode
Serial.print("Voltage 1: ");
Serial.print(voltage1);
Serial.println();

// Prints the current mode
Serial.print("Voltage 2: ");
Serial.print(voltage2);
Serial.println();

if(mode == 0){
// Sets the panel to 90 degrees when the light sensors have low light
if((voltage1 < 1) && (voltage2 < 1)){
gotoAngle(90);
} else {
// Gets the current angle of the panel.
angle = getAngle();
// Prints the current angle
Serial.print("Angle: ");
Serial.print(angle);
Serial.println();
// Compares the voltages between the two light sensors.
comp = abs(voltage1 - voltage2);
if(comp < 0.0075) {
// Turns both LEDs on if the panel is in the correct sensor positions
digitalWrite(lightCW, 5);
digitalWrite(lightCCW, 5);
// Sets the system delay to 1000ms. This is the rest time between sun tracking movements.
motorStop();
delay(1000);
} else if(voltage1 < voltage2) {
digitalWrite(lightCW, 0);
digitalWrite(lightCCW, 5);
// Only moves the panel if is greater than 30 degrees.
if(angle > 20){
// Controls the motor movement using the voltage comparison between the two photoresistors
motorMove(voltage1, voltage2);
} else {
motorStop();
}
} else {
digitalWrite(lightCW, 5);
digitalWrite(lightCCW, 0);
// Only moves the panel if is greater than 30 degrees.
if(angle < 160){
// Controls the motor movement using the voltage comparison between the two photoresistors
motorMove(voltage1, voltage2);
} else {
motorStop();  
}
}

// Delays the motor movement by 5ms
delay(5);
}
} else if(mode == 1){
// Turns the LEDs off if in Accelerometer mode
digitalWrite(lightCW, 0);
digitalWrite(lightCCW, 0);
// Goes to an accelerometer angle of 90 degrees
gotoAngle(90);
// Delays the motor control by 50ms
delay(50);
}
}
float getAngle(void){
// Reads the accelerometer voltage
float angleVoltage = analogRead(2);
// Converts the accelerometer voltage into an angle
angleVoltage = (angleVoltage - 396) * 0.826;
// Returns the panel angle
return angleVoltage;
}
void motorStop(){
// Clears the inputs to the motor.
digitalWrite(motorCW, 0);
digitalWrite(motorCCW, 0);
digitalWrite(enable, 0);
digitalWrite(lightCW, 0);
digitalWrite(lightCCW, 0);
// delay(10000);
}
void motorMove(float comp1, float comp2){
float scale;
float angle;
// Gets current angle from the accelerometer
angle = getAngle();
// Sets the scale for the pwm controlled motor speed
scale = 75*(abs(comp2 - comp1))/max(comp1,comp2);
if(scale < 30){
  scale = 30;
}
if(comp1 < comp2){
// Enables the motor driver
digitalWrite(enable, 5);
// Set the direction and speed of the motor
digitalWrite(motorCW, 0);
analogWrite(motorCCW, scale);
} else {
// Enables the motor driver
digitalWrite(enable, 5);
// Set the direction and speed of the motor
analogWrite(motorCW, scale);
digitalWrite(motorCCW, 0);
}
// Prints the current angle
Serial.print("Scale: ");
Serial.print(scale);
Serial.println();
}
void gotoAngle(float angle){
float currentAngle;
// Only runs when the panel is not at the correct angle
while(int(angle) != int(currentAngle)){
// Retrieves the current angle from the accelerometer
currentAngle = getAngle();
// Doesn't tell the motor to move unless the panel position is further than 1 degree out of sync
if(abs(currentAngle - angle) > 0.85){
// Calls the motor control function
motorMove(angle, currentAngle);
// Prints the current angle
Serial.print("Current Angle: ");
Serial.print(currentAngle);
Serial.println();
// Delays the function for 50ms
delay(50);
if(mode == 0){
return;
}
} else {
// Calls the motor stop function
motorStop();
}
}
}
void modeChange(){
// Changes the mode when the INT0 interrupt (Pin 2)
mode = !mode;
}
float getVoltage(int pin)
{
return (analogRead(pin) * 0.004992914);
// This equation converts the 0 to 1023 value that analogRead()
// returns, into a 0.0 to 5.0 value that is the true voltage
// being read at that pin.
}