Laser Tag Update 3/22/15

I seem to be updating every two weeks. But hey, I'm making progress.

My deliverables from two weeks ago were:

1. Distance tests
2. Adjust code to use multiple receivers and test them.

I completed the distance test for the first version of the tag unit.


Voltage for LED: 5 V
Resistance for LED: Seven (x7) 33 Ohm resistors in parallel, resulting in 4.7 Ohm total resistance.
Current for LED: 1.06 (max is 1A)
Lens Diameter: 3.49"
Lens Focal Length: 9.5" +/- 0.125"
Max Transmission distance: 339 yards.

So, 339 yards is far. I tested my unit, and I could make a light blink one city block away. Which is great. And also very over powered. I'm not sure people will like using a 3.5 inch diameter lens, but heck, it works really well. I had to send the tag multiple times for the receiver to see anything at 339 yards. I could hit the receiver effectively (could aim and hit in 1 or 2 shots consistently) at about 235 yards. These measurements are estimates based on my gate (I measured how far I walk normally in 10 steps, then counted steps back to the receiver). However, despite the inherent inaccuracy of the measurement, I am very pleased with this transmission distance. It is a big improvement over the 90 feet that I got with the 1 inch lens.

The other change that I made was to the code. I got github to work on all of my operating systems (Windows, Linux and Mac), so now I can work on the most recent version of the code no matter what OS I decide to use at the time. I am tracking the changes I make on github, which is a great way to update code and track changes. I can now have the tag unit read in a tag from an IR receiver on any of my digital input pins. I also changed how my timing function works, since I wasn't accurately reading in the times. Also, I'm not sure if I decided on using 750 microseconds as the protocol duration or 600 microseconds. Either will work, but I should pick one. Or experiment to find out which is better.

So, deliverables for next week or two:

1. Rewrite the bill of materials for the tag unit
2. Purchase three additional units

If I have additional time

3. Test tag distances with a 600 and 750 microsecond protocol duration. See if there is a difference. (or, test 500 microseconds versus 1 millisecond to see a more drastic version of how this breakdown effects tag distance).

Side notes:

I came across a video by Extra Credits on tangential learning. I think there are already great resources to teach people the basics of circuitry, electronics, etc. I don't have to make those. I could use laser tag as a method of giving people exposure to electronics and letting them dive into the details if they want to. I can't force someone to like this or to learn it. For now, I think I should put the tools out there and let people who want to find more dig into those tools and resources to explore more themselves.

Also, I want to turn this into more of a video game. There are things about video games that are great, and I feel that they would add to the enjoyment of this. Experience, shields, unlockables, overshields, mech suits, manned turrets, auto-turrets, grenades, sounds, music, mines, abilities, character selection, etc. I could pick a game and start porting content.I should probably keep a repository of all these ideas somewhere I can find them.

Leave a Reply

Your email address will not be published. Required fields are marked *