Competition IR Beacon - how does its physical setup compare to our beacons?

[DanL]

First of all, I'm asking about the physical setup, not the frequency of the pulses or anything like that - of course the signal characteristics are going to be what FIRST told us. The reason I'm asking this question is because I've been testing out my team's beacon in my bedroom. Despite what Kevin Watson has said on his faq, the shotgun approach still picks up reflections off just about everything - my carpet, my walls, my wooden furniture. Taking it down to only one emitter LED works a little bit better, but not much. Granted, testing it in a room as crowded as my bedroom will produce more reflections than the competitions setup will, but I'm counting on there are still going to be some problems. For the time being, I put pieces of translucent scotch tape to act as a difuser for the LEDs and receivers, and this has made it work slightly better.

Doing this, however, has caused me to wonder whether at the competitions, is FIRST also using some kind of difusing filter infront of the beacon, or are their beacons going to be just the LEDs exposed to the field. I'd like to minimize the sensitivity of my receiviers using translucent diffusers (i.e. scotch tape), but to get a reasonable estimate, I need to know whether FIRST is going to have just the LEDs exposed, or are they putting some kind of translucent material in front of their emitters to decrease the amount of light put out.

Anyone that attended any of the kickoffs get a good look at their beacons?

[Kevin Watson]

Originally Posted by SuperDanman

...the shotgun approach still picks up reflections off just about everything - my carpet, my walls, my wooden furniture.

Dan, I've updated the FAQ with another entry that addresses this problem that you and others have noticed in their testing.

Originally Posted by SuperDanman

...I need to know whether FIRST is going to have just the LEDs exposed, or are they putting some kind of translucent material in front of their emitters...

Nope, they aren't covered.

-Kevin

[DanL]

Originally Posted by Kevin Watson

Dan, I've updated the FAQ with another entry that addresses this problem that you and others have noticed in their testing.

Much thanks for that update explaining the gain circuit! I origionally had the slitted-shotgun approach you had on your webpage, but that was picking up reflections, so I thought I'd try the full shotgun approach, and when that didn't work, I added some translucent material to the end... I see now that I was only making it worse and worse - less ambient light got to the sensors, so they fired their sensitivity all the way up and picked up even fainter reflections. Went back to the slitted shotgun but with a desk lamp shining on it, and it works beautifully. Again, thanks for the information.