For this project we used a globe and created a window to show constellations. We use the switch on the globe to light it up. When it is lit up, it reperesents day time on earth and no constellations will be shown. Bur when you turn off the light, it's night time and constellations will appear. By rotating the globe, you change seasons and thereby the shown constellation inside the window. A lux sensor will be the component to decide whether the light is turned on or off.

Material list

Wall

Cardboard
30 LEDs
red and black wire
Arduino UNO
433 MHz reciver module
Breadboard
Paper
Tissue paper
Constellations printed on A3 paper
Hot glue
Jumper cables
1 9V battery
Resistors

Frame

Wood
Screws
Paint
Cardboard
Paper
Window
2 lift off hinge

Globe

Cardboard
2 9V battery
RFID reader
RFID breakout board
RFID tags (same amount as the number of constellations you wish to see)
433 MHz transmitter module
Arduino UNO
1 LED
Lux sensor
Breadboard
Jumper cables
1 resistor

Step 1: Wall: Mark the Positions of the LED

Use a tool to mark the position of the LEDs on the cardboard. Place the constellations one at a time and use these as templetes. Do not forget to mark the holes with some color so you can see which LEDs that are included in the same constellation. If there is LEDs from different that could be replaced with one LED and be reused in different constellations, make sure to mark those.

We started of with 12 constellations and ended up with four, one for each season. Here is the template for those.

Step 2: Wall: Attach the LEDs

Attach the LEDs with some hot glue. Use soldering to attach the wires.

Step 3: Wall: Zodiak Sign/information Boxes

To get some more information about the constellations, we chose to add some nice pictures of what the stars are prepresenting. They also displays which the current season it is.

Use some cardboard to make four boxes without a front side. Divide the space in the frame into four parts so you get what dimensions they chould be.

Put a LED in the back and hook it up with wires and place a picture backwards (picture facing inside the box)at the front. Do this with all the boxes.

Step 4: Wall: Code and Schema Constellations

void turnOnLeds(int newSeason) { //Turn on the pins for one constellation

//0 = winter

//1 = spring

//2 = summ

//3 = fall

switch (newSeason) {

case 0:

analogWrite(A0,255);

analogWrite(A5,255);

digitalWrite(8,HIGH);

digitalWrite(2,HIGH);

digitalWrite(3,HIGH);

break;

case 1:

analogWrite(A1,255);

digitalWrite(10,HIGH);

digitalWrite(5,HIGH);

digitalWrite(9,HIGH);

break;

case 2:

analogWrite(A2,255);

digitalWrite(4,HIGH);

digitalWrite(11, HIGH);

digitalWrite(6, HIGH);

digitalWrite(7, HIGH);

digitalWrite(13, HIGH);

digitalWrite(3,HIGH);

digitalWrite(9, HIGH);

break;

case 3:

analogWrite(A3,255);

digitalWrite(12,HIGH);

digitalWrite(7, HIGH);

digitalWrite(6, HIGH);

digitalWrite(13, HIGH);

digitalWrite(2, HIGH);

digitalWrite(5, HIGH);

break;

case 4:

break;

}

Step 5: Wall: Connect the RF Receiver

Add the RF receiver to the LEDs circuit. Pin 11 should be free and you should connect the receiver DATA pin there.

Also, it is highly important that you connect the receiver ground (GND) to a ground pin on the Arduino board and the VCC pin to the 5V pin on the Arduino. Pay attention as the receiver needs min. 5V at all times and if your battery is getting low, the circuit will stop working.

The battery "+" should power the Vin pin on the Arduino board.

The attached code works with the VirtualWire library for the receiver if you need further support. If the code will not work for you, we recommend you to start testing the RF transmitter and receiver with one of their examples.

receiver.ino
Download

Step 6: The Frame

Use the window as a templete and use wood to build the frame. Additionally paint the frame to make the finish look better.

Place the cardboard with the constellations inside of the frame. with the boxes on top of it. We used some cardboard to create a shelf to place the boxes on.

Cover the LEDs with some paper and additional some dark blue tissue paper to make it look more like a night sky.

To make it look more like a window, wrap some cardboard in paper and use it as a window sill.

Step 7: Globe: Light Up the Globe With a LED

Take the globe apart. Remove the old lamp from the lamp-holder and the old wire. Cut wire to remove the lamp connector, be sure to keep the switch. Connect the wires to the 9V battery. Replace the old bulb with an LED.

Step 8: Globe: the Lux Sensor

Place the lux sensor inside globe near the LED. You might need to adjust the values in the code for the on and off statements.

// Connections Light sensor
// ===========

// Connect SCL to analog 5

// Connect SDA to analog 4

// Connect VDD to power supply

// Connect GROUND to common ground

Step 9: Globe: the RFID Reader and Tags

Cut another piece of cardboard that fits in the upper half of the globe. Place the RFID tags onto it.

The RFID reader will detect a different HEX code for each tag, thus try your tag at first and check the print that will appear in the Serial Monitor.

Example:

a8006bbcadd2 - the correct print should have 12 characters in total

The HEX code will change every time you add more sensors to the circuit, thus always remember to re-test it. If you encounter to get 00000000000a, then your RFID reader receives too low voltage.

Step 10: The Globe: RF Transmitter and the Arrangement Inside the Globe

Cut a piece of cardboard. Place all the components onto it and attach it to the lamp-holder by using the old light bulb.

Connect the RF transmitter DATA pin to pin 12, the GND pin to the common ground and the VCC pin to the common voltage.

In the code, you will find a variable called 'msg' whose value is going to be sent to the receiver. Set 'msg' with 0 for winter, 1 for spring, 2 for summer, 3 for fall. However, the msg will be converted to bits and reconverted to a HEX value that you have to find out in the receiver Serial monitor.

We left a piece of code for you to test the transmitter by attaching a LED to pin 13. Every blink means that the signal is sent.