Before you watch this project... see my others:

- The "Scary Door"

- "Project Goldie"

 

 

C

http://twitter.com/Cabe_Atwell

 

New Year’s Eve (NYE) is always fun, especially when something fun happens at the zero time. Launching fireworks seems to be the default response to the calendar change. Having it do off exactly as the year comes to a close is key. The person that is often required to light those wicks loses out to enjoying that moment. (They have to be on the ready to do whatever task is needed…)

This project is for those lonely and wayward souls 

 

This setup and forget countdown timer that activates 10 relays for the last 10 seconds of the year. Like a switch, a relays can turn on/off anything that can be turned on/off. So, this project could just turn off all the lights in a house for a dark and private NYE, to blaring ten electric boat horns for the annoying party.

Do anything you want with the relays… I chose to launch a single firework at the zero second. I chose this mainly to give a simple way of handling launching of fireworks remotely. (I would like to add, much safer too. No more light the wick and run like crazy…)

 

Here were my requirements of the “CANYECT WFLA”:

  1. Grab the time from the Raspberry Pi clock.
  2. Countdown from any time showing DAYS:HOURS:MINUTES:SECONDS
  3. As the timer get closer to zero… it will truncate what is not necessary anymore, starting with days. Then hours, and finally minutes. On the last 15 seconds… the last numbers will fill the screen.
  4. On the last 10 seconds of the countdown, the RPi will activate (or deactivate) 10 relays.
  5. (For my example) Launch fireworks on the last second, wirelessly.

 

Project by sections

 

Hardware:


At the core of the project is the Raspberry Pi Model B Rev 2. Between it and the Sainsmart 8-relay board is a set of Adafruit Logic Level Converters. The Raspberry Pi GPIO pins only output 3.3V data signals… and the relay board is looking for a 5V potential to indicate a switch. The logic level converter handles that boost. You could build your own level converters with a 2N222 transistor as some resistors, but who has time for that?

From the relays board, I have bypassed one of the buttons on the JM70A Wireless Remote Control 4 Channel Kit. Why such a crude hack of the remote? I wanted to put together a simple wireless setup. I had a few wireless relays in my junk electronics, finally wanted to put them to use. For this project, I only needed one wireless relay.


I simple soldered wires to the either end of the JM70A button “A.” From there is connected to the last relay on the SainSmart 8-relays board on the “Normally Open” terminals. When the relay board is switched, the remote will think its button “A” is being pressed. That simple.

At the business end of the project is the 4-relay board, part of the JM70A kit. This board has four relays that could be used. I only needed one. To the Normally Open (NO) terminals of the relay I will activate, I attaches wires that connected to two CR123 (3V) batter holders in series (6V total), then to one lead of an Estes Model Rocket Igniter. The other lead connected back to the other NO connection on the relay.


When the relay is witched, 6V will dump through the Estes Rocket Igniter, which starts to burn. The Igniter is taped to the fuse/wick of the Fireworks I want to launch… the igniter burns.. so does the fuse.


Fun is launched.

 

You do not need to go wireless. Just use wires directly from the SainSmart relay board to your Igniters or whatever you are activating. Keep in mind, the longer the wire, the more resistance. You could attenuate your data signal. Test ahead of time.

I just wanted to not lay wires down like a WWII communications soldier. And.. I wanted to keep the Pi and parts safe from the burning materials.

 


Schematic and Design


Click to zoom in! (Build at your own risk...be advised!)

CANYECT WFLA LE1.jpg

Click to zoom in! (Build at your own risk...be advised!)



The difficulties

 

- The Estes Model Rocket Igniters, the ones you find in model rocket kits, are extremely delicate. Move it around too much, and the part that burns will break. There are plenty of sites that talk about building your own igniters.. However, I wanted something that is manufactured to work… but more importantly, available on Amazon.

Be careful with handling these. Also, keep in mind, they get “burn to the bone” hot, handle with caution.


- For some of us, NYE is a cold day. Although cold electronics often work better, batteries do not. I had trouble with some fireworks launch tests not working. I used a hardware store heat gun to warm them up before tests. Worked like a charm.

Alternatively, insulating the batteries is a good idea.


- The JM70A, both the control fob and the relay board needed 12V. The key fob had a battery holder, the relay did not. I bought a battery holder for a small 12V battery (N type). The relay board would be good for a few tests before the battery wore out. To about battery issues, I connected a 12V wall power supply to the key fob. Also, it saves a lot of batteries that way!


- Remember that the fuse on fireworks give some time for people to light and run away. So, if you set it at the zero mark, it will then take X amount of time to burn down. To account for this, I cut the fuse down quite a bit. Since I did not need to be near it to light the fireworks, I made it as short as I could. Also, placing the output at an earlier time could time it all better. IE: If is takes 3 seconds to burn a fuse, move the output to the relay for “3 seconds to go.)

 

 

Code (Build at your own risk...be advised!)


Everything you need to compile is attached to this post. Download, compile, and set up the relays.

 

To do a test of the countdown, press “Ctrl-T.” Each time you do, it will get closer to the last 15 seconds.

 

 

 

BOM

 

CANYECTWFLA BOM
DESCRIPTIONQUANTITYUnit PriceVENDORVendor Part#PRICE
Fireworks (Roman Candles, etc)3$7.00FW StoreNA$21.00
Estes Model Rocket Igniters (6 Igniters per pack)3$8.00Local Hobby Store2301/2302$24.00
Zitrades (SaneSmart) 5V 8 Channel Relay Module for Arduino DSP AVR PIC ARM1$14.25AmazonNA$14.25
Palm Touchpad 5V 2A microUSB power supply1$5.00AmazonNA$5.00
4-channel I2C-safe Bi-directional Logic Level Converter3$3.95Adafruit757$11.85
Raspberry Pi Model B2$35.00element1443W5302$70.00
PRE PROGRAMMED, MICROSD, 8GB, RASPBERRY PI1$17.99element1497W1422$17.99
BREADBOARD, SOLDERLESS, 400 TIE POINTS1$7.35element1456T0249$7.35
BUDGET PACK, RASPBERRY PI (Mostly unused, only for parts)1$49.95element1444W3511$49.95
BUD Boardganizer2$16.32element1488W3963$32.64
Total$254.03
Items found or for free
HDMI and HDMI to DVI cables
Keyboards and mice
Power strip
ASUS 24" LCD1$100.00EbayNA$100.00
Magnets, wire, wire nuts, solder,



 

Other uses of the system

Anything that can be turned on with or like a switch.

10 Creepy talking dolls

10 Old TVs on "no signal" fuzz

10 Appliances in someone’s house

10 Fibonacci sequenced CANYECT WFLA projects (advanced… and sounds insane)

 

C

See more news at:

http://twitter.com/Cabe_Atwell