Published March 11, 2018 © GPL3+

Lane Tech HS - PCL - IoT Smart Blinds

Adjust your blinds from the comfort of your seat without having to go through the effort of standing up.

BeginnerFull instructions provided2 hours3,490

Things used in this project

Hardware components

Particle Photon

Photo resistor

RobotGeek Continuous Rotation Servo

Breadboard (generic)

Jumper wires (generic)

Software apps and online services

Blynk

Story

This project was part of the Lane Tech HS Physical Computing Lab course. I created this project as part of the Home Automation / IoT project.

Background

This IoT home automation project eliminates the need to go through the troublesome process of having to actually get up and manually adjust your blinds. With the use of a photocell, motor, and a smartphone, you can have full control over your blinds from anywhere.

Creation

The creation process was simple as it only involved the assembly of the components along with the mounting of the parts into the blinds.

Wiring complete on breadboard

As for the mounting, some steps were needed to insert the motor into the blinds so that the blinds could be controlled. These steps included getting rid of the twist controller within the blinds as well as cutting out slits for to hold the motor in place and to pass through the wires.

1 / 3 • Blinds with twist controller

To be able to control the blinds, the motor must be attached to the blind rod to allow it to turn. Given the fact that the motor couldn't have been consumed in the project (ruling out any permanent solutions), I found a workaround involving a short piece of tubing with an inside diameter of about 3/16. Although the tube did not fit at first, some work was required to expand it so that it would fit over the head of servo. Once this was done, all that was left was to attach the tubing to the rod within the blinds so that the servo would be able to rotate it.

1 / 3 • Servo, blind rod, and tubing

From here, the only thing left was to hang up the blinds and mount the rest of the components to the wall.

Breadboard attached to plastic casing adhered to the wall

Blynk Integration

To add Blynk into the project, you must first create and setup a new project, which you can find out how to do here. As for the button themselves, map:

V0 to close fully

V1 to open fully

V2 to close a bit

V3 to open a bit

V4 to enable the photocell control.

Blynk configuration

Photocell Mode:

Blinds working in "Photocell Mode", where they will open/close automatically based on light outside

Blynk:

Blinds being controlled through input on Blynk

Close up view of the motor controlling the blinds

Future Improvements:

A couple features that would improve this project would be:

A sliding feature to precisely adjust the blinds to the user's desired position

A smaller motor with higher torque, allowing for a more discreet mounting within the blinds along with an overall easier time turning the rod.

Use of a custom PCB to eliminate the need for the breadboard and ultimately provide an easier time mounting the project.

Code

blinds.ino

#define BLYNK_PRINT Serial

#include <blynk.h>

char auth[] = "YourAuthKey";

Servo motor;
int potPin = A0;
int potReading = 0;
int motorPin = 0;
int photoVal = 0;
int LEDPin = D3;
bool hasRun = false;
bool photoMode = false; //Control solely with photocell

void setup()
{
    motor.attach(D0);
    Serial.begin(9600);
    delay(5000);
    Blynk.begin(auth);
}

BLYNK_WRITE(V0) {
    if (param.asInt() == 1) { // CLOSE FULLY
        motor.write(0);
        delay(1200);
        motor.write(92);
    }
}
BLYNK_WRITE(V1) {
   if (param.asInt() == 1) { // OPEN FULLY
        motor.write(180);
        delay(1200);
        motor.write(92);
    }
}
BLYNK_WRITE(V2){ // CLOSE A LITTLE
    if(param.asInt() == 1){
        motor.write(0);
        delay(300);
        motor.write(92);
    }
}
BLYNK_WRITE(V3){ // OPEN A LITTLE
    if(param.asInt() ==1){
        motor.write(180);
        delay(300);
        motor.write(92);

    }
}
BLYNK_WRITE(V4){ // TOGGLE PHOTOCELL MODE
    if(param.asInt() ==1){
        photoMode = true;
    }
    else
        photoMode = false;
}
void loop() {
    Blynk.run();
    
    potReading = analogRead(potPin) - 1023;

    if(photoMode){
        if(potReading<0){
            if(hasRun==false){
                Particle.publish("**OPENING**");
                motor.write(180);
                delay(1200);
                motor.write(90);
                hasRun = true;
            } 
            else{
                if(checkChange(potPin)){ 
                    hasRun == false;
                    Particle.publish("**CHANGED; CLOSING**");            
                }
            }
            Particle.publish("**STAYING OPEN**"); 
        }
        else{
            if(hasRun==false){
                Particle.publish("**CLOSING**");
                motor.write(0);
                delay(1200);
                motor.write(90);
                hasRun = true;
            }
            else{
                if(checkChange(potPin)){
                    hasRun == false;
                    Particle.publish("**CHANGED; OPENING**");
                }
            }
            Particle.publish("**STAYING CLOSED**");
        }
    }
    Particle.publish("Photoresistor value",String(potReading));
}

boolean checkChange(int pin){ // Test to see if there's a notable difference
    int init = analogRead(potPin);
    delay(1000);
    int final = analogRead(potPin);
    
    int difference = abs(init-final);
    if(difference > 300){
        return true;
    }
    else{
        return  false;
  }
}