The Ultimate Electronic Puzzle Box

There has always been something about puzzle boxes that delights me. Maybe it's the satisfaction of opening secret compartments. Maybe it's the series of intriguing puzzles the creator has meticulously planned out for you to uncover. Who knows? It might just be a mystery.

This is the third puzzle box I have made. This time around, I set out to create something that is currently a rarity in the puzzle box community. A well-designed mainly electronic puzzle box under $20,000 (no, seriously). I have been seeking this for a while, and am yet to find anything significant. So, I decided to make one myself.

This box includes 3 "layers". It does not have a set amount of puzzles, because I can code whatever puzzles I want with the sensors that I have integrated. But, I am planning for V1 to have about 10 puzzles to get to the final compartment.

I had a lot of fun (and frustration) while making this project, and I hope you find this Instructable useful!

This project requires basic knowledge of Arduino coding and wiring.

Since each puzzle box is different, unless you are trying to make an exact copy of mine, your materials will vary from mine. For that reason, I will not include links.

• Box:
• Box material (wood, carboard, ect.)
• Box adhesive (screws, zip ties, hot glue, ect.)
• Hinges for the lid
• Servos or solenoids (I used servos) for locking mechanism(s)
• Relatively weak springs (optional) to spring-load locked compartments for an element of surprise
• Electronics:
• Arduino Mega or Uno, depending how big your box is. I used a Mega.
• Various buttons, switches, keypads, potentiometers, and other input devices
• Various electronic sensors. I used the following types of sensors: sound, light, tilt, touch, and magnetic.
• Various output devices. I used an LCD screen, RGB LED's, a buzzer, and a solenoid to make tapping sounds inside the box.
• LOTS of Arduino-compatible wires
• Other supplies:
• Hot glue is a must. It will hold all your components in place.
• A power drill if your box is wood.

1. Think about the size and shape you want it to be. This is important, as this will affect the rest of the project.
2. Choose your material. I would suggest either cardboard or wood. Even though I used wood, my first box was cardboard. Cardboard is a lot more forgiving than wood, so I would suggest using it for your first box.]
3. Construct your box. You could use something as simple as a shoe box, or go the fancy route like I did and use screws to make a homemade wooden box.
4. Add your hinges. If you're using cardboard, you may not need hinges.
5. Optional: Paint or color your box.

1. Decide how many locking compartments you want. It's completely fine to just have the box lock and nothing else. But if you're feeling ambitious, take the time to add mini drawers and cabinets to the inside of your box. Don't overdo it!
2. Make your locking mechanisms. I used servos attached to the drawers that were blocked by a mini piece of wood. When I coded the cabinet to open, the servo would turn 180°, allowing it to open freely.
3. Add springs. Just make sure they're not too strong, or they could jam your mechanism and prevent your drawer from unlocking.
4. Test. Improve. Repeat. It took many attempts before I got my locking mechanisms running smoothly. You will probably have to redesign the locking mechanism(s) a couple times.

1. Mark with pencil where you will make holes. This means any LED, button, or physical puzzle that needs to stick out of the box should be marked first. Don't forget components like buzzers, that may need holes even though the user will not interact with them.
2. Make your holes. This means cutting if you're using cardboard, or drilling if you're using wood.
3. Fit-check. Improve. Repeat. It's better to start with holes that are too small and make them bigger then the other way around
4. Hot glue your components in place. A little bit goes a long way.

1. Hot glue your components in place. These might include sensors and other components such as relays.

1. Make a Google/Excel Sheet with all your components and what Arduino ports they will be connected to. This might seem overkill, but you will be grateful in the long run when you start to connect all of your components.

• Wire your components to the Arduino in a logical order. Make sure you don't tangle wires too much, or they might pull on each other.

• Set up and test all your components in Arduino IDE. If you just have a few components, this should go relatively smoothly. If you're like me, and you decided add lots of components, this process may take days. My best advice is to do everything in a very organized and logical order, as this will help you keep your head clear.
• Ask the smart people over at the official Arduino Discord server if you need help. I personally resolved a lot of issues this way.
• Don't give up. I would say this was absolutely the most difficult part of the whole project for me. Just keep resolving those bugs until all of your components are working properly.

• Brainstorm how you can turn your components into challenging, yet fun, puzzles.
• Code your puzzles, and string them together into one big challenge.
• Add a reward at the end. People need a motivation to solve your puzzle. This could be a little prize or a congratulations message inside the final compartment of your puzzle.
• Optional: Add a hint system. If you are up for the challenge, code in a way people can ask for and receive hints. This will make your puzzle box less frustrating to solve (I'll let you decide if that's a good thing).

• Add a backstory to your box. Maybe it washed up from the shores of the Caribbean, or was sent to you by a secret spy agency. Your creativity is the limit.
• Add appropriately themed decorations to your box. Use them to sell the backstory and make your box more interesting to solve.

• Put all your hard work to use. Invite people to solve your awesome puzzle box!
• Optional: you could make you box into a small business. Make your money back by renting it out for parties and other events.

• Just kidding! I hope you enjoy making your puzzle box as much as I did! Thanks for reading!