Project Code

Below are the Program for our Senior Design project.

Solar Tracking Program Code

#include <Servo.h>

// Currently for 4 solar tracker system 
const int debug = 0;
const int numPanels = 4;

// Motors - Directed by LDR 
Servo motors[numPanels * 2];
int motorPins[] = {8, 9, 10, 11, 12, 13, 14, 15}; // LoMotorOne, HiMotorOnce, etc...
int ldrPins[] = {A0, A1, A2, A4, A5, A6, A8, A9, A10, A12, A13, A14}; // LeftLDROne, RightLDROne, TopLDROne, etc...

// Bias indicates the observed difference between the installed light sensor pairs that needs to be corrected in code
int leftBias[] = {-12, -9, 10, 7};
int topBias[] = {-24, -1, 10, 10};


// Lower motor position limits
int loMotorPosL = 0;
int loMotorPosH = 270;

// Upper motor position limits
int upMotorPosL = 45;
int upMotorPosH = 135;

// The minimum difference between light levels to trigger a movement
int threshold = 5;

void setup() {
  // Check to see if debug mode is enabled
  if (debug == 1) {
    Serial.begin(9600);
  }

  
  // Initialize the motors for each panel
  for (int i = 0; i < numPanels; i++) {
    // Lower Motors
    Servo low;
    low.attach(motorPins[i * 2]);
    motors[i * 2] = low;
    
    // Upper Motors
    Servo up;
    up.attach(motorPins[(i * 2) + 1]);
    motors[(i * 2) + 1] = up;
  }
  
  delay(500);
}

void loop() {
  // Adjust the position of each panel
  for (int i = 0; i < numPanels; i++) {
    movePanel(i);
  }
  
  delay(50);
}

void movePanel(int panelIndex) {
  // Read the current motor positions
  Servo loMotor = motors[panelIndex * 2];
  Servo upMotor = motors[(panelIndex * 2) + 1];
  int loMotorPos = loMotor.read();
  int upMotorPos = upMotor.read();

  // Read the LDR data and offset by the observed variances (a lower value indicates more light detected)
  int leftLDR = analogRead(ldrPins[panelIndex * 3]) + leftBias[panelIndex];
  int rightLDR = analogRead(ldrPins[(panelIndex * 3) + 1]);
  int topLDR = analogRead(ldrPins[(panelIndex * 3) + 2]) + topBias[panelIndex];

  int avgTop = topLDR;
  int avgBot = (leftLDR + rightLDR) / 2; // Bottom LDRs averaged together
  int avgLeft = leftLDR;
  int avgRight = rightLDR;

  
  // Print out the LDR and motor data when in debug mode
  if (debug == 1) {
    Serial.print(panelIndex); 
    Serial.print(" Top: "); 
    Serial.print(avgTop); 
    Serial.print(" Left: "); 
    Serial.print(avgLeft); 
    Serial.print(" Right: "); 
    Serial.print(avgRight);
    Serial.print(" loMotorPos: ");
    Serial.print(loMotorPos);
    Serial.print(" upMotorPos: ");
    Serial.println(upMotorPos);
  }
  
  // Adjust upper motor position if the difference between top and bottom LDRs is greater than the threshold
  if (avgBot - avgTop >= threshold) {
    // In this case the bottom LDRs read higher than the top LDR, so the panel needs to be moved up
    // Make sure that the motor is not moved past the maximum degree
    if (upMotorPos < upMotorPosH) {
      upMotor.write(upMotorPos + 1);
    }
  } else if (avgTop - avgBot >= threshold) {
    // In this case the top LDR reads higher than the bottom LDRs, so the panel needs to be moved down
    // Make sure that the motor is not moved past the minimum degree    
    if (upMotorPos > upMotorPosL) {
      upMotor.write(upMotorPos - 1);
    }
  }
}  

Motor Testing Program Code

 #include <Servo.h> 
int botServoPin=8;
int botServoPos= 90;
Servo botServo;

int botUp = 1;

int topServoPin=9;
int topServoPos= 90;
Servo topServo; 

int topUp = 1;

int botServoPin1=10;
int botServoPos1= 90;
Servo botServo1;

int botUp1 = 1;

int topServoPin1=11;
int topServoPos1= 90;
Servo topServo1; 

int topUp1 = 1;

void setup() {
  // put your setup code here, to run once:
//Serial.begin(9600);
botServo.attach(botServoPin);
botServoPos = botServo.read();
topServo.attach(topServoPin);
topServoPos = topServo.read();
botServo1.attach(botServoPin1);
botServoPos1 = botServo1.read();
topServo1.attach(topServoPin1);
topServoPos1 = topServo1.read();
}

void loop() {
  // put your main code here, to run repeatedly:
  if (botServoPos < 113 && botUp == 1) {
    botServo.write(++botServoPos);
    botServoPos = botServo.read();
    // delay(75);
  } else if (botServoPos >= 113) {
    botUp = 0;
  }
  
  if (botServoPos > 68 && botUp == 0) {
    botServo.write(--botServoPos);
    botServoPos = botServo.read();
    delay(75);
  } else if (botServoPos <= 68) {
    botUp = 1;
  }
  
  if (topServoPos1 < 113 && topUp1 == 1) {
    topServo1.write(++topServoPos1);
    topServoPos1 = topServo1.read();
    // delay(75);
  } else if (topServoPos1 >= 113) {
    topUp1 = 0;
  }
  
  if (topServoPos1 > 68 && topUp1 == 0) {
    topServo1.write(--topServoPos1);
    topServoPos1 = topServo1.read();
    // delay(75);
  } else if (topServoPos1 <= 68) {
    topUp1 = 1;
  }

  if (botServoPos1 < 113 && botUp1 == 1) {
    botServo1.write(++botServoPos1);
    botServoPos1 = botServo1.read();
    // delay(75);
  } else if (botServoPos1 >= 113) {
    botUp1 = 0;
  }
  
  if (botServoPos1 > 68 && botUp1 == 0) {
    botServo1.write(--botServoPos1);
    botServoPos1 = botServo1.read();
    // delay(75);
  } else if (botServoPos1 <= 68) {
    botUp1 = 1;
  }
  
  if (topServoPos < 113 && topUp == 1) {
    topServo.write(++topServoPos);
    topServoPos = topServo.read();
    // delay(75);
  } else if (topServoPos >= 113) {
    topUp = 0;
  }
  
  if (topServoPos > 68 && topUp == 0) {
    topServo.write(--topServoPos);
    topServoPos = topServo.read();
    // delay(75);
  } else if (topServoPos <= 68) {
    topUp = 1;
  }

  delay(75);
}

Light Sensor Program Code

int ldrPin;
int ldrPin1;
int ldrPin2;//the number of the LDR pin
void setup() {
  Serial.begin(9600);
}

void loop() {
  ldrPin = analogRead(A0);
  ldrPin1 = analogRead(A1);
  ldrPin2 = analogRead(A2);
  Serial.print("A0 : ");
  Serial.print(ldrPin);
  Serial.print("  A1 : ");
  Serial.print(ldrPin1);
  Serial.print("  A2 : ");
  Serial.println(ldrPin2);
  delay(100);


}

Data Logger Program Code

#include <SD.h> // Load the SD Library
#include <SPI.h> // Load the SPI communication library
#include <Wire.h>
#include <Adafruit_INA260.h>
Adafruit_INA260 ina260 = Adafruit_INA260();

float Voltage;  // Variable for holding Voltage
float Current;  // Variable for holding Current
float Power;    //Variable for holding Power

int chipSelect = 10;
int ledPin = 8;
File SolarPanelData;

void sdFail() {
  Serial.println("Card failed, or not present.");
  digitalWrite(ledPin, HIGH); 
  while (1);
}

void setup() {
  Serial.begin(9600);
  Wire.begin();
  ina260.begin();
  Serial.println("Initializing SD card...");
  pinMode(10, OUTPUT);
  SD.begin(chipSelect);
  if (!SD.begin(chipSelect)) {
    sdFail();
  }
  Serial.println("Card initialized.");
}

void loop() {
  Current = (ina260.readCurrent())*(0.001);
  Power = (ina260.readPower())*(0.001);
  Voltage = (Power/Current);
  
  SolarPanelData = SD.open("Data.csv",FILE_WRITE);
  
  if(SolarPanelData) {
    Serial.print("Current: ");
    Serial.print(Current);
    Serial.println(" A");
  
    Serial.print("Voltage: ");
    Serial.print(Voltage);
    Serial.println(" V");
  
    Serial.print("Power: ");
    Serial.print(Power);
    Serial.println(" W");
    Serial.println();
  
    SolarPanelData.print(Current);
    SolarPanelData.print(",");
    SolarPanelData.print(Voltage);
    SolarPanelData.print(",");
    SolarPanelData.println(Power);
    SolarPanelData.close();

    delay(10000);
  } else {
    sdFail();
  }
}

Proposal Report

Design Report

Design Report

S.T.A.R.S

Project Code

Solar Tracking Program Code

Motor Testing Program Code

Light Sensor Program Code

Data Logger Program Code