SparkFun Forums

[niwnfyc]

My fiancée and I are getting married in about a year, and being an electrical engineer, I thought it would be fun to incorporate some sort of electronics into our wedding. What I would really love to do is design something small and simple that every guest could take home. Help me design it!

It needs to be something that a non-technical person could look at think is cool (meaning it can't be something like a little chip programmer that only a technical person could appreciate).

I'm thinking something involving some blinking LED's, but nothing too obnoxious since all 200 guests might have theirs turned on all night.

I also might want it to be customized for every guest (possibly a scrolling LCD with their name for their place card?). Yes I know I'll have to program 200 separate firmwares, but that could easily be accomplished on a rainy day.

As for cost, I've set aside $2000 for this. This means that I can spend $10 per person since there will be 200 guests. I'll be able to get the pcb's for about $1-3 a piece, so that leaves me with around $7-9 for parts.

So if you were to show up at my wedding and receive a little circuit board that does something, what would it do that would make you go, "COOL!”?



Some requirements:
1. Must not be a real product already (I want to make it myself)
2. LED Throwies are not an option

[dattaway]

I have learned through the years that many at the wedding want to know where the newlyweds are going to have their honeymoon. Their goal is to crash your private escape and attempt every prank in the book. This often brings great joy to the mother in law who doesn't want to lose the constant company of her "handyman" son around the house.

Help them by giving each a simple radio finders to track and locate your heavenly retreat.

[Encryptic]

Temperature sensing coasters? Based upon the temp of the drink on the coaster the some LED's could blink in different patterns?

Low power RF transmitter's broadcasting some types of unique messages from guest to guest, displayed on some type of LED matrix (thinking cheep)?

Something cool to look at for an idea, is the Defcon 2007 Badge, it had some neat things, and when you waved it back and forth you could see a secret message.

Just throwing out some ideas!

[Philba]

The Atmel butterfly costs (still available???) $20. It has an LCD, an AVR and a couple of buttons. You might use that as a point of departure to design something along the lines of what you were talking about.

Personally, I like the idea of an electronic "mood ring". This would have a temperature sensor and when people hold it it in their hand the temperature would be used to light LEDs in different patterns or colors. I'd use a diffuser to combine the colors. An LCD version could say cute or annoying or funny things.

[Encryptic]

A project I forgot about that's called Sinister7, which was done here by one of the SFE guys, perhaps that would give you some ideas too.

[daemondust]

Maybe something with an ez430 and RGB LED's? TI sells MSP430F2012 boards for 3.33 each. They'll happily run off a 1.5v battery (AA/AAA type or button cell) without any regulation. They have a built-in temperature sensor, too.

Between the uC board and LED that would take you to just about $5 per, so that leaves half the budget for whatever packaging you want. I like Encryptic's idea of a temperature reactive coaster.

[bigglez]

What I would really love to do is design something small and simple that every guest could take home. Help me design it!

Greetings (No Name Supplied),

Congratulation to you and your fiancée! I have two suggestions,
one has already been revealed on this forum, read more here.

The other one I have working as a prototype and I'm looking
for a payday (probably a published article in a hobby magazine),
so I can't share the concept today.

However, once the ink in dry on my manuscript contract I'll let
you have a peek - you (and your guests) are going to love it!!

Comments Welcome!

[niwnfyc]

That 8x8 led matrix looks pretty cool.

A price breakdown for 200 guests (from digikey):

12,800 LED's @ $0.049 a piece: $627.20
400 shift registers @ $0.14638 a piece: $58.55
200 pcb's (4PCB) @ $3.72 a piece: $744
200 PIC's (16F628A) @ $1.65 a piece: $330.00
200 Battery holders @ $1.03 a piece: $205.68
400 AA batteries @ $0.315 a piece: $126.00
Misc. Parts: $250


Total: $2342

I'm sure that could be reduced somehow.

[bertrik]

I think it would be cool to able to communicate with other devices, e.g. through a simple infrared protocol. Perhaps even make some kind of ad-hoc network.

Ideas:
* Each device remembers which other device it has already seen. When two people come near each other, but who haven't met yet, the devices detect that and start blinking in sync (and/or with a specific color/pattern) for example.
* Pressing a button on one device sends a signal to other nearby devices, causing a 'wave' of blinking leds. Or make all devices in range blink in sync or in patterns.
* Each device could be assigned a gender so devices can pick a random dance partner of the opposite sex by blinking in sync for example. Or maybe pick two people from the different families.
* Maybe some kid games (hide and seek?)
* Make some special devices (to be worn by you) that can control the others, like make them light as you come near.

Instead of just blinking lights, you can do nice things with multi-colored LEDs and controlling them through PWM, so they can smoothly change color and glow instead of blink.

[Pyrofer]

If you can get them in decent quantity the old Nokia 3310 LCD is SIMPLE and each to connect to even the smallest 8pin PIC.
You could still fit in a couple of lines for IR in/out and have interactive badges with graphic LCDs.

[NleahciM]

That 8x8 led matrix looks pretty cool.

A price breakdown for 200 guests (from digikey):

12,800 LED's @ $0.049 a piece: $627.20
400 shift registers @ $0.14638 a piece: $58.55
200 pcb's (4PCB) @ $3.72 a piece: $744
200 PIC's (16F628A) @ $1.65 a piece: $330.00
200 Battery holders @ $1.03 a piece: $205.68
400 AA batteries @ $0.315 a piece: $126.00
Misc. Parts: $250


Total: $2342

I'm sure that could be reduced somehow.

You could do the PCBs for alot cheaper than $744, if you don't mind supporting the communists on the other side of the big pond. I would expect that that'd bring your total cost down to below $2K. Gold Phoenix is a good place to start, but there are many others out there as well.

[bigglez]

It needs to be something that a non-technical person could look at think is cool (meaning it can't be something like a little chip programmer that only a technical person could appreciate).

I'm thinking something involving some blinking LED's, but nothing too obnoxious since all 200 guests might have theirs turned on all night.

Greetings (Still No Name...),

I see that you have some good suggestions. My wife and I were
kicking around the concept over dinner last night.

Here's another avenue to think about. Each guest is given a
plain box with no instructions and no obvious switches or
buttons. The box is totally blank, but fairly small. (Think
about those RF coasters that restaurants use to call guests
when their table is open).

After a while, perhaps by accidentally dropping one or two
of these on the floor, it will become apparent that the
mystery box responds to physical movement (it has an
accelerometer).

Over time the shaking or further knocking gets an LED
message to appear, one letter at a time or one segment
at a time - we want the game to last a while and keep
everyone interested. The box is dark red plastic but the
LEDs can be seen through it. (These are commercially
available from Hammond).

Perhaps there is a prize for the first one to decode the
clue or message? Perhaps there is no contest - just
a little cube that spells out your names and wedding
date when shaken. Perhaps it gives advice at random
like the "8-Ball" or "Sinister-Seven" toys?

After a few seconds it goes back to sleep...

Remember the KISS principle. I'd avoid complex
assembly, exotic parts, or RFID, etc. You probably
won't have a rehersal to iron out the bugs.

Comments Welcome!

[blarggstar]

Build little devices that have one LED and RF transmitter/receiver. Of the 200 devices, only a few devices could be lit at a time. The lit status would randomly get passed around the party.

Each person gets the light for 10 seconds, then it runs away....

If you wanted more options, put three LEDs on each device and get creative!

Don't know how hard it would be to create this, or if it would be that cool, but, that's my idea!

Congrats and Good luck!

-Ben

[John Meacham]

http://www.instructables.com/id/Programmable-LED/

It is exceedingly simple yet pretty cool. you shine light on it in a pattern, then it repeats that pattern back at you.