Invisible Infrared Sign

Technical Technical Discussion
#1

My team is interested in creating an aesthetic sign on our robot but we want to make it cool. Our goal as of right now is to use a sheet of some type of material to create a sign that glows with infrared light and thus will only be visible to ir cameras. We have a plan for increasing the intensity of our ir emitter but are having trouble finding a way to make a certain portion of the sign glow with it still being invisible. Any input is well appreciated.

For reference, we want the effect of this table by Mark Rober and how he made the words digitaldudes glow but by having it glow with exposure to ir light and be invisible to the naked eye. https://youtu.be/SaG-NQ64540?t=55s

#2

R07: ROBOT parts shall not be made from hazardous materials, be unsafe, cause an unsafe condition, or interfere with the operation of other ROBOTS

C: Any devices or decorations specifically intended to jam or interfere
with the remote sensing capabilities of another ROBOT, including
vision systems, acoustic range finders, sonars,** infrared proximity
detectors**, etc. (e.g. including imagery on your ROBOT that, to a
reasonably astute observer, mimics the retro-reflective features of
vision targets described in Section 3.13 Vision Targets)

While it is not intentional, it could be considered to violate this rule because the IR light of your decoration could be picked up by IR sensors and produce junk values. This could be interpreted as interfering with remote sensing capabilities.

That being said, it is certainly an interesting idea. :smiley:

#3

Your right. We just think it will be a cool offseason project and a cool learning experience with the electronics and mechanical implementations of it and if we do implement the design we plan to make it so that the emitter will only be active while the robot is disabled and we don’t plan to install the system while the robot is still in competition.

#4

First make it work with visible light (LEDs). Use clear polycarbonate sheet, etched (frosted, as shown in the video) for your letters (they WILL be visible, just not very).

Then use IR LEDs to replace the visible LEDs. These don’t usually come in strips like in the video, instead as individual LEDs, but are not difficult to connect to a power source, just be sure to use a dropping resistor to limit LED current based on source voltage. Soldering is necessary, and check the power rating of your resistor to be sure it will not overheat.