Fireworks, Revision 3

The 3rd one is always a good one ;)

Firmware (arduino C++ code), Layout as PDF.

Revision 3 of the fireworks board:

All layers.

Bottom layer.

Top layer.

Everything is now much tighter packed! I decided to use RJ45 to connect every six-pack of rockets (spare 2 pins used as 12V power supply). The arduino's FTDI port can be easily used with an FTDI breakout board.

Lession learned:

• Use small pads only where needed (in tight spots)
• Pull out all available ɥC pins
• plan mount holes
• put as much as possible onto the lower layer (easier to solder)
• 8705 is a very useful power regulator when used with 3-5 cell LIPOs

Hardware documentation is available as PDF or you can get the whole source code including pcb (beta version).

Fireworks, the first prototype PCB

Yay, today I made the first prototype PCB. Already soldered the absolute minimum onto it for tesing.

Top layer, with Arduino Pro mini 5V (top) and a single 8 bit shift register (below the Arduino).

Bottom layer.

The final layout will certainly differ from this a bit. I did not know how painful it is to solder headers which have connections on the front layer. Thanks to swiss machine pins it is possible without funny chemicals.

Also, the copper around  the via and pin holes are much too small. They make drilling and sometimes proper soldering very hard. It's just looks ugly too.

Further more, a new design decision was to use RJ45 as connector for the expansion to the electric fuses (connectors at the bottom).

Back to the drawing board!

Fireworks!

Not much time left until it is Silvester. The remote controlled fireworks launcher is in prototyping stage. I got the first PCB layout together.

The pcb files are created with an open source program called pcb (free as in free code and free of charge) which should compile on nearly all UNIX like operating systems (incuding, osx, cygwin or mingw for windows).

The pcb application is also able to generate gerber files which are included in the pcb files download.

Some alpha code (written in C)  is available to be run on an Arduino Pro Min 5V.

This project builds on the knowledge gathered from 8 bit shift registers and Arduino in general.

Special thanks goes to Sämi for all his valuable input.

Circuit



Front side



Back side