Shawn Murphy
Published © GPL3+

Single Axis Solar tracking for large roof top panels

This project has been designed to get the maximum solar output from limited rooftop space on our off-grid solar powered Art Studio.

BeginnerWork in progressOver 1 day632
Single Axis Solar tracking for large roof top panels

Things used in this project

Hardware components

Arduino Nano RP2040 Connect
Arduino Nano RP2040 Connect
×1
Linear actuator
×2
Drok DC Motor controller 6.5V-27V 7A PWM Motor Regulator Board
×1
LDR, 1 Mohm
LDR, 1 Mohm
×2
Resistor 10k ohm
Resistor 10k ohm
×2
Drok DC to DC stepdown Buck Converter
×1

Software apps and online services

Arduino IoT Cloud
Arduino IoT Cloud
Arduino IDE
Arduino IDE
Visual Studio Code Extension for Arduino
Microsoft Visual Studio Code Extension for Arduino
Fusion 360
Autodesk Fusion 360

Hand tools and fabrication machines

Harbor Freight DRILL MASTER 6 in. 5.5 Amp Cut-Off Saw
Makita Angle grinder
Programmable DC Power Supply (0-30 V 0-10 A) 110V
qidi X-CF Pro 3d printer

Story

Read more

Custom parts and enclosures

3d printed shader for LDR sensors with mount

this is a solar shader I designed in fusion 360 that blocks the sun until the sun moves from one LDR sensor to the other. It has insets for the LDR's with pass-through holes for the LDR wiring. I will 388 electronic silicone in the LDR hole first to waterproof it.

Schematics

rough schematic

This is the rough schematic for the setup.

Code

Arduino Cloud code for single axis panel lift

C/C++
This code moves the panels based on LDR sensor data. There are variables for:

sensorValue1
sensorValue2
threshDiff
threshDiff_PM
threshold (modifiable)
useSensor (move by sensor or move by web button)
panelUp (web button)
panelDown (web button)
panelStop (web button)

There are some averaging functions that I have not implemented, but may in the future. As you can see, they are commented out. Initially, I wanted the code to be as simple as possible, and may actually not find a good reason to average out the raw values.
/* 
  Sketch generated by the Arduino IoT Cloud Thing "Untitled"
  https://create.arduino.cc/cloud/things/72fdc536-58ed-467c-82a3-170dbd1a36ee 

  Arduino IoT Cloud Variables description

  The following variables are automatically generated and updated when changes are made to the Thing

  int sensorValue1;
  int sensorValue2;
  int threshDiff;
  int threshDiff_PM;
  int threshold;
  bool panel_Down;
  bool panel_Stop;
  bool panel_Up;
  bool useSensor;

  Variables which are marked as READ/WRITE in the Cloud Thing will also have functions
  which are called when their values are changed from the Dashboard.
  These functions are generated with the Thing and added at the end of this sketch.
*/

#include "thingProperties.h"
const int Extend = 6;
const int Retract = 7;

int sensorPin1 = A1;
int sensorPin2 = A2;



int counter = 0;
//int valAverage1 = 0;
//int valAverage2 = 0;
int numAverage = 10;


void setup() {
  // Initialize serial and wait for port to open:
  Serial.begin(9600);
  // This delay gives the chance to wait for a Serial Monitor without blocking if none is found
  delay(1500); 

  // Defined in thingProperties.h
  initProperties();

  // Connect to Arduino IoT Cloud
  ArduinoCloud.begin(ArduinoIoTPreferredConnection);
  
  /*
     The following function allows you to obtain more information
     related to the state of network and IoT Cloud connection and errors
     the higher number the more granular information you’ll get.
     The default is 0 (only errors).
     Maximum is 4
 */
  setDebugMessageLevel(2);
  ArduinoCloud.printDebugInfo();
}

void loop() {
  ArduinoCloud.update();
  // Your code here
  //valAverage1 =0;
  //valAverage2 =0;
  if (useSensor) {
    for (counter = 0; counter < numAverage; counter++) {
      sensorValue1 = analogRead(sensorPin1);
      sensorValue2 = analogRead(sensorPin2);
      threshDiff = (sensorValue2 + sensorValue1);
      threshDiff_PM = (sensorValue2 - (sensorValue1 + threshold));

      //valAverage1 = valAverage1 + sensorValue1;
      //valAverage2 = valAverage2 + sensorValue2;
    }

    //valAverage1 = valAverage1/numAverage;
    //valAverage2 = valAverage2/numAverage;

    //Serial.print(valAverage1, DEC);
    //Serial.print(", ");
    //Serial.println(valAverage2, DEC);

    if (sensorValue1 < sensorValue2 + threshold)
    {
      digitalWrite(Extend, HIGH);
      digitalWrite(Retract, LOW);
      delay(1000);
      digitalWrite(Retract, LOW);
      digitalWrite(Extend, LOW);
      delay(500);
    }
    else if ((sensorValue2 + sensorValue1) < 100)
    {
      digitalWrite(Retract, HIGH);
      digitalWrite(Extend, LOW);
      delay(500);
    }
  }
  
  // If useSensor is false, read the button state and turn on/off the relay based on it
  else {
    if(panel_Up == HIGH) {
      digitalWrite(Extend, HIGH);
      digitalWrite(Retract, LOW);
    }  
    else if(panel_Down == HIGH) {
      digitalWrite(Extend, LOW);
      digitalWrite(Retract, HIGH);
    }
    else if(panel_Stop == HIGH) {
      digitalWrite(Extend, LOW);
      digitalWrite(Retract, LOW);
    }
      
  }




  Serial.print("sens_1 ");
  Serial.print(analogRead(sensorPin1));
  Serial.println();
  Serial.print("sens_2 ");
  Serial.print(analogRead(sensorPin2));
  Serial.println();
  Serial.print("Threshold Difference ");
  Serial.print(threshDiff);
  Serial.println();
  delay(1000);


}


/*
  Since Threshold is READ_WRITE variable, onThresholdChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onThresholdChange()  {
  // Add your code here to act upon Threshold change
}

/*
  Since UseSensor is READ_WRITE variable, onUseSensorChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onUseSensorChange()  {
  // Add your code here to act upon UseSensor change
}

/*
  Since PanelUp is READ_WRITE variable, onPanelUpChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onPanelUpChange()  {
  // Add your code here to act upon PanelUp change
}

/*
  Since PanelDown is READ_WRITE variable, onPanelDownChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onPanelDownChange()  {
  // Add your code here to act upon PanelDown change
}

/*
  Since PanelStop is READ_WRITE variable, onPanelStopChange() is
  executed every time a new value is received from IoT Cloud.
*/
void onPanelStopChange()  {
  // Add your code here to act upon PanelStop change
}

Credits

Shawn Murphy

Shawn Murphy

3 projects • 7 followers

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