Hi all,

I recently got involved with FIRST, and we're working on some final tweaks to 
the robot.  [ For others in FIRST, our team did not get funding in time for 
this year's event, but we're still working on the robot for educational 
purposes and for an unofficial local-area competition in the fall ]. 

One of the boards we have is an IR receiver board with 4 outputs, and which 
works with regular TV/DVD remote controllers (trainable).  We want to use 
this as a backup control during the hybrid (autonomous and 
operator-controlled) mode, but need a 360-deg field of view for the receiver, 
with a max range of about, say 50 feet (I'm mentally estimating here).  We 
have only one more meeting this coming weekend, so I'm looking for a quick 
way to improve this if possible.  My options...

(1) Relocate the IR receiver module component (TSOP34838) higher off the board 
to keep it clear of other components.  The case for the IR receiver seems to 
be some type of semi-translucent material so it does function with the 
control at the back of the unit.

(2) We can aim it upwards but the reception from the side is very low. Some 
type of circular/conical mirror may be necessary, but getting something 
suitable within 5 days seems questionable at this point.  BTW, other teams 
have reported that stray signals have been an issue with these boards, as the 
overhead lap counters in competition are IR based, so there will need to be 
an overhead shield for this.

(3) From the datasheet, the IR receiver module component has an NPN transistor 
switch at the output with a 30kohm pullup to Vdd (+5V).  Perhaps I can 
piggyback another one of those on the same board and point them in different 
directions.  This has the advantage of being able to mount the 2 IR receiver 
modules at opposing sides of the center column on the robot, so it will clear 
mechanical obstacles on the robot itself.  However, it has the disadvantage 
of picking up additional stray signals, and causing signal confusion, with 
less reliability.

(4) Add another IR board and OR the outputs.  Pretty sure this won't happen in 
5 days.

I think (1) and (2) seem reasonable at this point, given the 5 days to do 
this.  Any thoughts on this?  Or any other quick ideas?  As a backaup 
solution for an unofficial competition, I am not so interested in making it 
perfect as I am in showing the kids how to go about solving this problem to 
improve the system within the short timeframe.

Cheers,
-Neil.

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