My team is building a competitive robot as part of our course work. As all of us are using the sharp IR sensor, I;m thinking of ways to confuse opponent's readings.
So far, here's the list I've come up with:
1) mirrors to deflect IR--pasting mirror surfaces around robot
2) IR jam--using IR leds to shoot out beams in all directions
I'm thinking of using uneven surfaces that will diffuse the IR beam (not tested yet).
The good thing about IR (from a sensor point of view) is that most common objects ‘look’ the same in the IR spectrum. Many normally transparent objects like glass appear opaque, and the colour of an object also has little to no impact on the sensor. The sharp IR range sensors are designed to be able to detect a black matte wall under full sunlight, so you’ll have to think creatively to trick them.
The glass surface of a normal mirror will tend to scatter the IR back into the sensor before the silvered backing can reflect it, so they’re not likely to help much. If you can find some stick-on mirror sheets (the thin plastic ones) you should find these much more effective, and not nearly as heavy.
A rough, uneven or matte surface will only help direct the IR back into the sensor, so it will actually help them to work instead of hinder them. If you really want to divert the incoming IR, you can make a ‘light trap’ by using a honeycomb pattern of holes on the outer surface of the bot. One way to do this would be to cut some plastic drinking straws into short lengths (a few cms or so) and bundle them together lengthways. Fix them to the outside of the bot with the holes facing outwards. When the IR beams hit the bot, most of the IR will travel into the straws, and won’t find its way back out to the sensor, so the sensor can’t see anything.
This page is a useful reference for an overview of how the sensors work, and what kind of performance you can expect from them.
Thanx telefox, i’ll try out the honeycomb design. and thanx for the link for the sensors, it’s very informative.
Sad to say, I can’t make the helicopter as we only have a standard kit from Innovation First, which comes with 2 wheels w servo + some modular building mterial.