A Smart Nought and Crosses

Hello everyone,

I am Djordy van Ringelesteijn a student Mechenical engineering at the Hogeschool Rotterdam.

I am second-year student, I decided to chose Fablab Smart Object as my first subject.

We had the instruction to make a smart object, a smart object is an object that responses to his surrounding by using sensors.

I decided to make a smart nought and crosses, the reason I made this is because I want to eliminate the chance of cheating and i want the arduino to tells who won.

The second reason I wanted to do this was cause I couldn’t find anything the same as this on the internet. So I had to begin totally from scratch.

At the beginning I struggled a lot with it , I though it wasn’t possible cause I couldn’t find the right sensor for my project, i eventually made smart use of the arduino UNO.

List of items:

The electric part:

· 1 Arduino UNO

· 9 10KΩ resistance

· 2 LEDs (prefer two different colours)

· 1 220Ω resistance

· A lot of jumpwires (9 around 20 cm are required )

· 1 830 pins breadboard (I used this in the testing phase, not necessary)

· 1 small breadboard

· 9 reed sensors (prefer to buy more cause they are really fragile and a lot of them didn’t made it to the end).

· 10 Little magnets(you can use anyone you like, just adjust the model, I used one with a diameter of 8 mm and 1,5 mm thick).

Other items I bought:

· A little wooden stick, around 3 mm in diameter and 5 cm.( i used a cocktail stick)

· PLA(I used different colours )

Tools and extra’s :

· a laptop( that has arduino and inventor(i used inventor2017 for the 3d-models))

· a 3D printer

· Tape

· A hammer

· Some buddy.

· Soldering iron

· Solder

· A wire cutter

· A multi cutter

Step 1: Making the Box

The biggest part is printing the box, the box is 150x150x50 mm, there are 2 holes for the Arduino UNO, I made them so I could put my cable in the Arduino UNO without having to open the box every time. I also can adjust the code and test it without opening.

i made the box using white PLA, because it was the biggest roll i had and it took a while to print, i also wanted to make the plate made in the next step to have the same color as the box so it looks like one piece.

Step 2: The Plate

The plate will be used to place the nought and crosses on , so the reed sensor will be placed in this plate. As you can see on the image above there are 9 slots with 2 holes each to place the reed sensors. There are also 3 other holes, the 2 holes next to each other are used for the LEDs, the other hole in the corner is used for the reset button, I will explain this later as we assemble all parts.

Step 3: The Nought and Crosses

I made some round holes in the nought and crosses, the holes are 8 mm in diameter and 1,5 mm deep. The holes are for the magnets. I made 5 rounds and 5 crosses, this so it doesn’t matter which person starts.

Step 4: The Reset Button

I printed a little button to use as reset button, i used a different color PLA so, it would be more visible .

Step 5: The Electric Circuit

Now we have all parts printed we can start making the electric circuit, for the electric circuit I use the parts from above(see list of electric parts).

I used a bigger breadport (830) so it is easier to attach and test the reed sensors for final design i used a smaller breadport .

For the LED attached to pin 13 there is no resistance cause, there is already one in the Arduino UNO in pin 13.

I used diodes instead of reed sensors in the picture above, because there weren’t any reed sensors in the program I used for making the schedule so, all diodes are actually reed sensors.

The LED has a 220Ω resistance, all reed sensors have a 10K Ω resistance.

Step 6:

Step 7: The Code

The code does say whose turn it is, it also counts the turns so it knows if it is a cross or round in the code.

If player 1 is on turn a red light will blink if it is player 2’s turn a yellow light will be blinking, the color depends on which color you used.

All 9 cells are “A” if the turn match the value of the if-statement and the reed sensor == 1 and the cell value is still “A” the value will turn into a “X” or a”O” depending on which turn it is.

At the end of the code the code will look at all the cell values and see if it matches one of the if-statement, if it does the LED of the player who won will turn bright for 10 seconds.

the code will loop until someone won the game.

Step 8: The Sensors

I first put all reed sensors in place and thigh them with some buddy to keep them in place.

After I finished this I put some tape on one side of the box and opened it like the picture above.

on the picture above I placed the breadport right behind the Arduino UNO, this is to keep the Arduino UNO in place in to the two holes and for the reset button.

I also placed the 2 LEDs in place.

Step 9: Soldering

I soldered all wires together according to the electric circuit I showed and made at step 5 , I also placed the wooden stick on top of the reset button of the Arduino UNO keeping it in place using some buddy.

Step 10: Closing the Box

I gently closed the box pushing all the jump wires in the box and making sure the wooden stick we placed in step 9 above, make sure the stick sticks out the hole we made in the plate. if you are sure the wires are soldered together correctly you can chose to glue the box and plate together, there will be pressure from the cables if you push them in, this will open the box every time. I decided to just use a little bit of tape because, the reed sensors are really fragile and I had to replace them many times. The wooden stick we placed in before is sticking out of the hole of the reset button, I just cut it off and placed the button I printed in

Step 11: The Nought and Crosses

At last, you have to put the magnets into the rounds and crosses, I used a hammer and some carton the hold between the hammer and the magnet to prevent it smashing the magnet in piece and so the magnet didn’t stick to the hammer, I then gently hammered the magnet in the hole cause it is a really tight fit, you can chose the make the hole for the magnets a little bigger and glue them together.