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!?