Using invisible inks with IR sensitive camera to read instructions from QR Codes, April codes or Glyph for Indoor Navigation
OK, so the first prototype started on a full side Roomba with a bluetooth type controller with a 2.4ghz analog camera. I don't think this camera works anymore because the battery has lived it's life so I am moving to another setup for the second go around.
Three prototype Invisible QR code readers version 2
Ceiling View NAV Sensor
This is the original intent of the QR code navigation , but the utilization does not stop here. Also not everyone has a ceiling within height they have access to apply a QR code. In that case walls or floors even may be more useful. Even 12 foot ceilings can use the vertical QR NAV beacons.
Forward View NAV Sensor
These are the most straight forward navigation beacons. Everything from doors, doorway edges, or even charge docking. They could be placed on elevator doors and under the elevator call button for service robots.
Floor Facing Macro View NAV Sensor
Though this is the least obvious, businesses or homes with smooth floors like tile, wood or even concrete can use this method. It also would work on sidewalks, driveways and roads. This version of the sensor can clearly focus on codes .5 inches away and .25 inches in size. TINY RIGHT!?
So the robot arrived, if you don't mind having no instructions whatsoever and nothing lining up then this is the kit for you. It took a few tried before I found holes that would work for two layers but they are not symmetrical. The package was for two turtle bots ,but the package was ripped open and much of the hardware missing. There is no labeling on these either. I may rethink using this as a test platform and 3D print something to go on top of the rover 5 4x4 with encoders instead. We will see and I will update you.
The frame I ordered for testing purposes appeared to finally arrive. The package was damaged and likely some pieces are missing. I will start assembly so I will have a platform to start playing with.
Here I could have used a extra pair of hands , but it was just a quick test before bed after filling cartridges. I overplayed the IR ink onto the UV and the contrast really pops! Much better that IR on white paper by itself, when UV light is off you can see the camera picks up the IR ink on white paper as dark gray. Remember the longer term is invisible tags which in most cases means clear or Matt clear adhesive labels on printable sheets.
The pictures loaded in weird places on my phone so I will fix that tommorow on a pc.
IR only with the IR camera-
I filled cartridges will all the inks I have. I am likely to use noodlers and the UV absorbing ink , but I will start testing different labels soon. I picked up a Epson Workforce printer that uses these cartridges for 89 dollars from Office Depot. I believe I will dedicate the printer to making these invisible tags as to not mix inks.
Noodlers White versus UV yellow, very close , but the yellow is 5 times the cost!
ok so the UV inks I ordered made for a inner cartridge came in. I am slightly disappointed because the red is practically non existent. Anywho I compared them to noodlers ghost bullet proof inks and the white and green inkjet inks were much brighter. As I mentioned before I am considering using both IR and UV for maximum contrast in any lighting conditions or lack there of.
All are normally invisible without special lighting , filters or camera.
Top - not visible is magenta
2nd- white UV
3rd- blue UV
4th -green UV
5th- Noodlers Ghost UV
Tests against white paper is neeto,but the goal is to make invisible markers so I will print onto Matt or clear plastic. I put some on my finger of the green as well as the noodlers ghost white, the green is a tiny bit brighter. It is so close!!
Next is to start filling ink cartridges
This is UV ink on normal white paper, with a drawn white, of course the marker pen is 2mm tip . You can use your phone with a QR code to read by looking at this picture. It is my email address as a sample. The edges are not sharp, but my cell phone still reads after a couple seconds. I think this is good enough to proceed to the next step which is printing UV ink through an inkjet printer so the code is sharp and readable from afar.
Here is a UV reactive ink from Noodlers, a UV ink manufacturer for pens. One thing I noticed it is very thin , so it wets the paper more, I think I need a substance that has more UV pigments inside. This is the first UV tests. I want to have at least two inks in QR codes. The reason has to do with a variety of lighting conditions, different inks work better. Low light for example UV is king, but daytime IR absorbing looks grey even in daylight. QR codes can be any color, they operate on principles of contrast. As long as one is brighter than the other is should work.
So the video was uploaded sideways because that's apparently what my phone wanted. Good news is I'm switching to a galaxy Note 3 in a day or two. Looks like this will work fine and now I can get back to building beer bot. The next step is figuring out how many codes I want to use. I will need to buy a compass I believe next.
it's a very short video just showing that the code cam be moving some as long as it's slow enough to grab a frame. I also tried reading the code without the IR light and it would not read at all without direct illumination at 7 ft away using a 400 x 400 line Qr code.