Help with a Haunted Chessboard!


Hello, and thank you for your time! :blush:

My brother and I are building spooky puzzles for kids to solve during a Haunted House Activity. And one idea we have involves using littleBits! But I just donโ€™t know how yet! :confounded:

We want to have a chessboard, and picture of two ghosts playing chess above it. As the kids do activities throughout the haunted room they win chess pieces, if theyโ€™re really clever, and place their chess pieces on the chessboard so that it matches the picture - a secret door pops open! :unlock:

The basic idea is when the chess pieces are placed on the chessboard, it completes a circuit and this signals a servo to unlock a secret door. :bulb:

The secret door is a challenge for another time! Right now Iโ€™m trying to figure out how to hide a circuit in a chessboard!

One idea we have is sticking two pins through a few squares of a wood/cork chessboard, and painting the bottoms of the chess pieces with conductive paint. On the bottom of the chessboard is a circuit that has gaps where the pins are. By placing the chess pieces over all the squares that contain the two pins, the circuit is completed! :white_check_mark:

The only thing we donโ€™t like about this idea is the pins will likely be visible on the board in order to make contact with the chess pieces, slightly ruining the effect. :weary:

My brother had the idea of using magnets on the bottom of the chess pieces. and under the board having magnetic coins/washers inside short plastic guiding tubes. When a magnetic chess piece contacts the board, itโ€™s proximity sends the washer up the tube and into contact with the circuit. This means no contact pins showing through, but takes a little more setting up. Still, I like that it feels less mechanical, and more haunted! :ghost:

Does anyone else have any other ideas on how to discreetly hide a circuit in a chessboard? My brother and I are entirely inexperienced with this sort of thing, and any suggestions/ideas would be greatly appreciated! :smile:

Thanks again!

  • Eidrog


1 Like

@eidrog, Iโ€™d like to introduce you to @alexpikkert, someone who enjoys the art of keeping people in suspense about how a project works.
Check out AlexPikkertโ€™s Projects. Heโ€™s FULL of ideas! :smile:

1 Like

Hi @JackANDJude,
Jude, thank you for this compliment !
I really enjoy sharing my ideas with other Littlebit fansโ€ฆ
Some ideas you could use in your haunted chessboard:

Use a lightsensor, set it to dark = action. Mount it under the board with a small hole and when something is placed on the little hole the sensor is set in the dark and you activate things.

Use a roller switch or a button mounted under the chessboard and activate it with a small pin through the board.

The pressure sensor could work also, but needs relative much weight.

I think the light sensor will be the best solution, maybe you buy a few moreโ€ฆ

I am working on a magnetic switch, built with the proto bit. When finished I will show the details.
Please show your project when ready, I love to see it !

Another trick popped up in my mind:
Use only one (1) light sensor and mount glass fibre wires under the chessboard, all with one end on the sensor.
As long as there is one wire sending light to the sensor, nothing happens, only if the all are dark then the sensor will act and could move a servo. I hope this works, I never tried itโ€ฆ:laughing:

Thanks @JackANDJude, for the introduction! And thank you @alexpikkert for the great suggestions! I really canโ€™t wait to recieve my littleBits kits in the mail and try some of these solutions out! :kissing_smiling_eyes: :envelope:

Currently the reed switch is one of my favorite solutions! :heart_decoration: This seems to be an effective way to achieve the result Iโ€™m looking for :ghost: โ€“ but I hadnโ€™t even considered using a light sensor :high_brightness: to detect when chess pieces are placed - or the pressure sensor. :point_down:

Youโ€™ve really armed me for success! :sparkles: Thank you very much! :smiley: . Iโ€™ll definitely share pictures once I get something working! :construction_worker: :camera:

1 Like

Hi @Eidrog @JackANDJude,
There might be one other solution that crossed my mind.
(One idea triggered another)โ€ฆ
Use only one light sensor and provide a number of chessboard squares with a clear or transparant part and mount the sensor under the board.
Each chess piece must cover the transparant part and can only block the light from one square. The result will be that the sensor is ONLY set in the dark when all chess pieces are placed on the board.
Voila !

@Eidrog look at this project:

This sounds like a fun project and it appeals to my mischievous nature. No surprise that @alexpikkert picked up on this one :smile:

In terms of the board itself I have had great luck working with cigar boxes which come in every shape and size and some would be perfect for a chess board with some bits hidden inside. Check out my LittleBits Express project to get an idea. It would also be cool if you used some magnets to move pieces on the board by themselves as I did in that project. I have made some improvements to this design since I posted it and now use some pulleys and string instead of the chain drive. This allows me to make the thing MUCH thinner.

To build on alexโ€™s idea, if you add a few logic bits with the light sensor you could set it up so several pieces need to be place to cause the action. You could also trigger an mp3 player to play (or say) something spooky once the pieces are placed correctly.

Perhaps the makey makey could come into play here.


1 Like

Hey Alex,

I would love to see any work in progress on your magnetic switch. If this becomes a bit of some sort, you might consider having some folks build some projects around it. I can think of lots of applications for a magnetic switch. I believe that someone made one that failed to get 1000 votes. It would be interesting to see what they did and why it may not have garnered the attention that it needed.


1 Like

Hi @Eidrog @joey,
Joey, your cigar box idea is very interesting !
I think it will be fully invisible โ€œhowitsdoneโ€ when the top cover is replaced by a transparant sheet (non-look-through but light goes through) and the squares that are not used are covered on the inside.with black paper.
Then , when you put a chess piece on the squares that are still transparant you make the inside only dark when ALL pieces are placed.
Just an ideaโ€ฆ

Hi @joey,
Joey, see the forum posts on Magnetic reed contact
There you can follow the progress.
I am not sure if my magnetic reed switch is good enough for the bitlab, @JackANDJude : what is your opinion on this ? .

This forum is amazing! Thanks for all the feedback! :smiley:

@JackANDJude I had a look at the ghost-projector, and that sounds pretty interesting! At first I thought, projector? I canโ€™t afford a projector for projection effects! :moneybag::movie_camera::moneybag:

And then I realized it was a projection effect that didnโ€™t require a projector! Awesome! :high_brightness: :arrow_right: :ghost: :ghost:
Thanks for sharing!

@joey the idea of moving pieces around after everything is set in place is great. It makes me want to put the king in check โ€“ and then the final piece moves forward, slaying the king!! :joy: (With appropriate sounds, of course!) :loud_sound:

@alexpikkert Thanks for the great suggestions! :grin: My littleBits will be arriving this Friday, or early next week, :truck: :email: and I canโ€™t wait to try out different set-ups and see what works best! :bitstar:

Re: Magnetic Reed Switch Bit, I think it would make a fabulous bit! Initially I thought you couldnโ€™t properly integrate it into littleBits, because littleBits uses magnets, so the reed contact would always be in a magnetic field, and thatโ€™s not-very-helpful. But then I see @alexpikkertโ€™s video where he moved the reed contact away from the rest of the little bits with a length of wire. :wavy_dash: It looks like it would be an awfully handy bit to have! :heart_eyes:


@Eidrog, I hope you can join us for this monthโ€™s Community Call! Itโ€™s today at noon, EST. :slight_smile:

Thank you very kindly for the invitation @JackANDJude . :smiley: Unfortunately I couldnโ€™t make it because I was at work all day today. :construction_worker: But it happens each month, huh? :open_mouth:

Iโ€™ve received my littleBits in the mail, and Iโ€™ve had all sorts of too much fun prototyping with them! :ghost: Theyโ€™re are going to be the perfect tools :wrench: :hammer: :electric_plug: for adding something special to our Haunted House! :yum:

Also, as Iโ€™m bound to get over my head and hopelessly confused, Iโ€™m going to be heavily relying on the good advice of folks here! :joy: Thank you very much for all the help so far! :blush:

Youโ€™re very welcome, @Eidrog. No need to wait until Halloween to post fun projects on the project page: ! :wink:

Hi @Eidrog. Check out the projects by @Artengine:

Some look like they would go well in a haunted house. :smile:

1 Like

Hi @Eidrog,
Can you share some progress on your haunted chessboard? I am curious to see if it worksโ€ฆ :alien:

You might also consider the makey=makey bit.

I have used the bare-conductive version to make invisible switches, It would be fairly easy too make a chess board square with a pattern that would match a similar pattern on the bottom of the chess piece.

@Eidrog Iโ€™d love to see as well! In fact, we might be announcing a haunting Halloween challenge very soonโ€ฆ :speak_no_evil: :jack_o_lantern: :ghost: