Escape Room Puzzle Tutorial - 'Symbol Wheels'

Learn how to create an escape room puzzle in which players must rotate a set of stone discs so that all the symbols along their touching edges match. The position of each disc is monitored by an Arduino and, when the puzzle is correctly solved, a relay is activated, releasing a key from a maglock.
I'll illustrate how I used Inkscape to design and layout the symbols on the stone discs, which I cut on a CNC router (though you could easily create these using hand tools and paint the symbols on). I used Minizinc to model the puzzle logic and ensure that only one unique solution existed, and the Arduino IDE to program the puzzle controller.

Timings
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00:00:00 - 00:02:23 Introduction and demonstration
00:02:24 - 00:08:21 Creating the design and layout
00:08:22 - 00:19:12 Modelling the puzzle logic
00:19:13 - 00:23:48 Building the prop hardware
00:23:48 - 00:27:45 Electronics wiring
00:27:46 - 00:36:36 Arduino code
00:36:37 - 00:37:48 Wrapup

Software Used (all free and open-source 😊❤️ )
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Hardware Used
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#escaperoom #arduino #puzzledesign

[SpiceMuffins]

My man did it again! He literally can't stop making awesome puzzles!

[LionTree]

I adding this puzzle to my Mayan Jungle Rescue. I spent the afternoon designing some vector's for the CNC! Thx for everything you do for the ER community.

[playhelps-gamesforgood]

Hi Alastair, I have been watching your videos since you started and they have always been a great inspiration for my own puzzles. Recently I have been going back over some of the older ones and even in this one, , after 4 years there is the same little smile of joy and satisfaction on your face when the maglock pops! Thanks for your enthusiasm!

[acps]

You are literally a genius. Massively underrated. Wish i could learn from you sir!

[stevenw]

What an amazing puzzle! Plus, I never knew about that art program and that'll definitely make my puzzle making easier for even my online puzzles!

[gercovanstraten]

As always, awesome puzzle and even better explanation. Thanks again!

[kuyaerwin]

Very nice my dear friend, uou are very creative sending my hugs and support, lovelots👍👍

[mfx]

Inductive sensors are quite cheap these days and you can then use a metal plate/disc on the back giveing a more controllable/defined and less critical detection area.

[DowntheWrabbitHole]

This is awesome! I wish you were my neighbor and could just make me things like this for my escape room games. I'm too chicken to dive into the world of arduino and electronics by myself, but I'd LOVE LOVE LOVE to have puzzles like this in my escape rooms.

[mfx]

An interesting twist for harder level games would be to have a table with the center disc painted on it (fixed) and six empty spaces with holes around it you'd then have to find or "earn" the outer discs and as well as line them up you'd also have to figure out the correct location for each disc to start with.

[applejuice]

Hello! I'm starting to build my first puzzles, these are extremely helpful! Thank you very much :)

[markgearing]

I’m going to guess it’ll take a maximum of six tries, the six different orientations of the centre wheel. For rapid solving, on each orientation you can dismiss it if two other wheels forming a triangle with the centre wheel can’t simultaneously match symbols with each other and the centre.

As for what’s going on in the background, it could be as complex as an Arduino or as simple as a series circuit of reed switches to drive a relay on the maglock.

Nice puzzle. Could be intimidating or quick depending on how you approach it. Now to watch the video and see how I did.

[manyshadesofbrown]

You should definitely create a course covering escape room design

[DAveShillito]

Very nice :)

One comment... you showed Minizinc checking that the arrangement you provided had only one correct solution, but how did you reach that arrangement?
Was it a case of manually entering possible patterns in Minizinc and testing until you found one that worked?
Or is there a programmatic method of approaching that side of the problem?

Either way, I now want to build one of these, even though I have no use for it at all :)

[jengalli]

do you have a library or something for the relay and mag lock on fritzing?

[DjairGuilherme]

If you place any of the disks in any of the positions and the disks are aligned with the magnets in the correct positions, the system will unlock the lock. The only way to ensure that the system opens the lock using only the correct alignment of the symbols on the disks is to keep the disks secured to the main board.

[catworldtoast]

Where can you get a Giant Key like that?

[abencomo]

Very cool tutorial! Thank you for putting it together and sharing it. Do you think you can recreated it using Unity to run it on smartphone or tablet?

[escaperoomescapades]

Hi, Alastair! If you were to add the lazy susans, you would increase the distance between the board and the disks. Would this be problematic in terms of the magnet sensors?

[fthef]

Thank you for the instructions. I’ve made the puzzle but have a bit more to do. One issue is with power. Only having the 12v power to the relay wouldn’t power the relay or nano. I had to add another 12v power to the breadboard that I have the nano on. Is that how it should work? Is it ok to have 12v directly to the breadboard with the nano? Thank you