LED Matrix for High Power Saucer Rocket | 16x8 Pattern Flashing Lights

[sailmike]

This is a LED lighting project that will go into a high power rocket shaped like saucer. Because this is a high power rocket, it must be launched at a certain distance from spectators for safety reasons. The launch pad will be at least 200-300 feet from spectators and rocket may go as far as 1000 feet from the ground. Flashing lights are easier to see than non-flashing lights. Lights flashing in a pattern are even easier to see from a distance and this is why I'm doing a LED matrix.

I'm currently in the preliminary planning stage. Things to think about for this project:
1. Lights will be on for a maximum 1 to 1.5 hours.
2. The power supply will be a lithium polymer pack outputting a maximum of 16.8V.
3. Matrix will probably be 16 columns x 8 rows. (this may change)
4. Lights need to be bright enough to be seen from a distance.
5. Saucers use aerobrake recovery rather than parachute recovery, so the whole circuit needs to be light.
6. Would like flashing pattern to be changeable via a pushbutton.
7. A voltage cut-off circuit will be needed to prevent over discharging the batteries.

I'm posting my project here so that I can get some help with it. The circuit I'm thinking of using is described here: http://www.instructables.com/id/LED-matrix-using-shift-registers/step1/Parts/

The time the lights will be on may actually be around 30-45 minutes, but I put down 1-1.5 hours as the outside estimate. There are so many LED's out there that I don't know which ones to pick. If any of you have ideas, I'm open to suggestions. I would think a high viewing angle and high brightness coupled with lowish current and voltage would be best.

Also, I'm not familiar with the HEF4794B and MIC2981/2982 chips. I could use a tutorial on how they work.

Here are some pictures of my saucer fleet and the big pink one lifting off on a K185 during a daylight flight. Also posting a picture of the circuit I'm thinking of using. If you think another circuit would be more suitable, please let me know.

Your help is appreciated,
Mike

 

[berkeman]

Welcome back to the PF.

Can you describe the timeline of a typical launch and flight? I'm not seeing the long LED display battery life needed yet. And given such a small saucer, how do you trace out a message visible from a distance?

 

[sailmike]

The saucer will be 20" in diameter, so it'll be reasonably large for a LED matrix. I don't plan to display message, just a pattern like rings of light moving up or down or bars of light moving around clockwise or counterclockwise or both.

A typical launch involves bringing the rocket to the range safety officer (RSO) who inspects it to make sure its safe for launch and assigns a pad to me. I then go out to the pad and set the rocket on the pad and connect the power leads to the engine igniter. The launch control officer (LCO) will launch rockets in the order received so everyone can get their rockets launched and not wait too long. Not many people fly at night, so the wait time between the RSO inspecting the rocket and launch might be 10 to 45 minutes depending on how many people are flying. Then, once the rocket lands, I'll need to be able to find the rocket in the dark. Saucers typically land close to the pad, so the walk to retrieve it won't be long.

Mike