Published July 17, 2016

Weasley Clock (Magical Location Clock)

Inspired by the Weasley Clock from Harry Potter, track your family using their phones' GPS! Create using limited programming knowledge.

IntermediateFull instructions provided12 hours2,419

Things used in this project

Hardware components

Particle Photon

I would suggest purchasing their beginners pack. The pack includes the small wires you will need. Also, the book gives you a good overview if you are new to programming and electronics.

Clock

Choose one which you like. I suggest looking for broken clocks at your local thrift stores.

USB-A to Micro-USB Cable

Also, a corresponding wall charger.

Foam board

Size it to your clock.

Spray Paint

Both white and black cans, one of each.

Foam Alphabet Stickers

The foam allows for easy removal.

Software apps and online services

IFTTT Maker service

Hand tools and fabrication machines

Hand Drill

Soldering iron (generic)

Hot glue gun (generic)

Story

Introduction

I saw tbornottb3's viral post on Reddit about the Weasley clock he made for his family as a gift, and was inspired. I, however, did not have access to digital design programs or a laser cutter. So, I set out to create a similar product which could be created in my living room with tools I already had.

https://www.reddit.com/r/DIY/comments/45sae8/harry_potterinspired_family_clock/

The clock's "magic" is created using the Photon and IFTTT (If This Then That). The IFTTT app on my phone tracks where I am. And when I leave a predesignated area (my home), it sends a signal out over the internet, which is received by the Photon. The Photon then turns on the light which corresponds to me leaving home (Lost).

Thanks to tbornottb3, this project requires very little programming, only alterations to his original code. The electrical work is limited to mimicking my electrical circuit and soldering three wires to pins. Mostly, this is a hardware craft project, and is very accessible.

Hardware

Alright, you have all of your supplies, let's begin.

1. Tear down that clock. Strip it to the basics.

2. Cut the foam board to fit the back of the clock.

3. Tape the light tracing paper to the back of the clock. (I forgot this step in my own project.)

4. Glue the foam board into the back of the clock. Let dry.

5. Take your electric drill and drill through the marked light locations. Deburr the clock face.

6. Spray paint the clock surface white. Let dry.

7. Using a pencil, mark the clock into six sections.

8. In the center of each section, mark the location for the lights. The locations will vary per clock, but try to make it symmetrical.

9. Trace a clock hand onto some thick paper six times, and cut them out carefully.

10. Using blue painters tape, tape the traced clock hands onto the clock face along the penciled section lines. Ensure you apply minimal tape, and only at the paper ends.

11. Apply the alphabet letters to make the words within the center of each section. The six sections I used were Home, School, Lost, Mortal Peril, Work, Church. Don't press down to hard on the letters, you will want to remove them without removing the paint beneath.

12. Spray paint the clock surface black. While wet, remove the stickers and the paper hands. Carefully, spray paint over the ugly white patches left by the painters tape with black without ruining the white clock hands or letters.

Programming

1. Follow the Set Up instructions for the Particle at https://docs.particle.io/guide/getting-started/intro/photon/

2. Go to the build website https://build.particle.io/build

3. Paste in my code.

3a. This code is written for 6 people, and 6 locations. If you wish to change either of those numbers, you'll have to understand and alter the code. Hopefully my minimal comments will help you understand it enough to alter.

4. Change the initials at lines 29-34 and 39-44 to the initials of your choosing. I chose the second letter of my family's names because they were all different.

5. If you wish to change the locations, alter the lines 19-24. Ensure they are only one word, no spaces.

6. If you wish to change the colors per person, alter the Hexidecimal code on lines 19-24. Google "Hexidecimal Colors" for the whole spectrum. I chose these colors because they were distinct and bright.

7. Download the code to your Particle over WiFi!

Electronics

1. Build up the circuit as shown below. Red wire is power, Blue wire is ground, and White wire is data.

1a. Remember, electricity is dangerous, both to you and your electronics. Double check everything before you turn on the power, and be careful.

1b. Most of the electronics information I needed I gathered from the Particle website. If you have any questions, they have excellent guides.

2. Turn on the circuit, and figure out where all of the lights belong by sending false signals to the Particle using IFTTT. (We'll cover that next.) Then plug them in their holes, and tape some cords to ensure they stay.

3. I had extra lights, so I lined the outside of the clock with them, to enhance the initial swirl.

IFTTT

1. Each family member must download the IF by IFTTT app on their phones.

2. Each member must create their own account.

3. Connect their account to your particle account.

4. I suggest Wifi triggers for Android, or location triggers for either Android or iPhone.

5. Let's build the home Recipe.

Create a new recipe.

Select the Location action

Select You Enter an Area

Find your home, and click next.

Select the Particle action

Select Call a Function

Select your function name.

Delete the suggested input. For my original code, I would put "A home". This is because A is my second initial, and is specified in the code, and home is a recognized location in the code. This will now turn off A's current light, and turn on A's home light.

6. Create 6 triggers for each person.

You have plenty of other options beside WiFi and Location. Experiment. Some of my family members use the stock market or the weather to light up certain lights.

Additional Sources

The viral Weasley Clock

His Code

His Imgur

Incredibly good guide on working with NeoPixels

A mechanical magic clock

Another mechanical magic clock

Enjoy!

Code

Weasley Clock

// This #include statement was automatically added by the Particle IDE.
#include "neopixel/neopixel.h"
#include <stdio.h>
#include <string.h>
#include <math.h>

int number_for_key(String key, struct entry dict[]);

#define PIXEL_COUNT 50


Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXEL_COUNT, D3, WS2812B);
int brite = 3;

struct entry {
    String str;
    int n;
};

struct entry places[] = { //After the first letter and a space, write this word in IFTTT
    "peril", 1,
    "lost", 2,
    "school", 3,
    "home", 4,
	"church", 5,
	"work", 6,
    0,0
};

struct entry people[] = { //This letter should be first character in IFTTT
    "I", 1,
    "E", 2,
    "B", 3,
    "A", 4,
	"M", 5,
	"D", 6,
    0,0
};

struct entry colors[] = { //Defines the color for each name.
    "I", 0x00ff00,
    "E", 0xff0000,
    "B", 0xffff00,
    "A", 0x00ff80,
	"M", 0xff00ff,
	"D", 0x0000ff,
    0,0
};

//name=people=capitalized letters

int updateClock(String command) {
  int commaIndex = command.indexOf(' '); //locate the space
  int secondCommaIndex = command.indexOf(' ', commaIndex+1); //locate the second space, starting one character after the first space
  String name = command.substring(0, commaIndex); //name's value is the string starting at the beginning and ending before the space
  String loc = command.substring(commaIndex+1, secondCommaIndex); //loc's value is the string starting after the space and ending before the second space
  int person = number_for_key(name, people); //check for match between the string, name, and people then record the number of the person
  if(person != 0){
	  flashB(number_for_key(name, colors)); //send color code to flash B for name
	  int place = number_for_key(loc, places);
	  if(place != 0){
	      
		  allMineOff(person);
		    int personcolor = number_for_key(name, colors);
		  	int red = floor(personcolor / (256*256));
            int green = (int)floor(personcolor / 256) % 256;
            int blue = personcolor % 256;
		  strip.setPixelColor(7+person+6*place, strip.Color(green, red, blue));
		  strip.show();
	  }
  }
  return 1;
}

void setup() {
    Particle.function("updateClock", updateClock);
    //pinMode(buttonPin, INPUT);
	strip.begin();
    strip.show();
	startupSwirl();
	strip.setBrightness(80);
	allOff();
	for(int j=1; j<=6; j++) { // set everyone to home
	    strip.setPixelColor(7+j+6*4, strip.Color(255, 255, 255));
	}
}

void loop() {
    strip.show();
    strip.setBrightness(50);
}

int number_for_key(String key, struct entry dict[]){ //checks the given name with the list of names allowed, returns number of match
    for(int j=0; j<6; j++) {
        String name = dict[j].str;
        if (strcmp(name, key) == 0)
            return dict[j].n;
    }
    return 0;
}

//This swirl is just for flashiness, only occurs on start up.
void startupSwirl() { // outer hands counterclockwise, inner hands clockwise
	int swirldelay = 50;
	for(int j=0; j<2; j++) {
    	for(int i=14; i<50; i+=3) {
    		allOff();
    		strip.setPixelColor(i, strip.Color(255, 255, 255));
    		strip.setPixelColor(62-i, strip.Color(255, 255, 255));
    		strip.show();
    		delay(swirldelay);
    		
    		allOff();
    		strip.setPixelColor(i+2, strip.Color(255, 255, 255));
    		strip.setPixelColor(62-i, strip.Color(255, 255, 255));
    		strip.show();
    		delay(swirldelay);
    	}
	}
}


void flashB(int hexValue){
	int red = floor(hexValue / (256*256));
    int green = (int)floor(hexValue / 256) % 256;
    int blue = hexValue % 256;
	for(int j=0; j<5; j++) {
		for(int i=0; i<14; i++) {
			strip.setPixelColor(i, strip.Color(green, red, blue));
		}
		strip.show();
		delay(300);
		for(int i=0; i<14; i++) {
			strip.setPixelColor(i, strip.Color(0,0,0));
		}
		strip.show();
		delay(300);
	}
}

void allMineOff(int n) {
	for(int i=7+n; i<PIXEL_COUNT; i+=6) {
		strip.setPixelColor(i, strip.Color(0, 0, 0));
	}
	strip.show();
}

void allOff() {
	for(int i=0; i<PIXEL_COUNT; i++) {
		strip.setPixelColor(i, strip.Color(0, 0, 0));
	}
	strip.show();
}

void debug(String message, int value) {
    char msg [50];
    sprintf(msg, message.c_str(), value);
    Spark.publish("DEBUG", msg);
}

Credits

Nathan Braaten

1 project • 1 follower

Thanks to tbornottb/ tbornottb3.

Weasley Clock (Magical Location Clock)

Things used in this project

Hardware components

Software apps and online services

Hand tools and fabrication machines

Story

Introduction

Hardware

Programming

Electronics

Additional Sources

Schematics

Weasley Clock Circuit

Code

Weasley Clock

Credits

Nathan Braaten

Comments

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Weasley Clock (Magical Location Clock)

Weasley Clock (Magical Location Clock)

Things used in this project

Hardware components

Software apps and online services

Hand tools and fabrication machines

Story

Introduction

Hardware

Programming

Electronics

Additional Sources

Schematics

Weasley Clock Circuit

Code

Weasley Clock

Credits

Nathan Braaten

Comments

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