Robot draws on walls and doesn't get in trouble

Sabrina Raaf, an artist from Chicago, has created Translator II: Grower, a robot that slowly traverses a room's wall drawing green lines that reflect local carbond dioxide levels.  It supposedly mimmicks the growth of grass, since grass also needs CO² to grow.  The more CO² in the area, the higher the line.  Joy.  Kids, if you get busted for drawing on the walls, just show mom this thing.  She'll realize what you're doing is a heady, artistic installation, and that you should be rewarded for your efforts.  Oh, and does anyone have any idea what Translator I was?