Figure 7 (a) shows one of safety signs used in public areas.
These graphical marks are prescribed in ISO 7010:2003 and people know their meaning all over the world.
The graphical marks are also used at shelters and they are convenient for people.
Adding to QR code to the mark provides useful information to both people and robots.
Figure 7 (b) shows one example of QR code that contains the same information to people (Turn Right, Forward 10m) and robots (R, 180, F,1000, E).
The messages to human and to robots are not necessary the same one.
Easy-to-understand messages are better than precise ones, for example, turn right and go to exit.