Varför är GERTY smutsig?

Detta behandlas i en artikel med prop-maker Bill Pearson. Kort sagt, roboten behövde se ut som den hade varit i kontinuerlig användning i femton år och hade lidit av försummelse och missbruk av sina tidigare användare (något som fungerar som en ledtråd och / eller förskuggning till twist i filmens ände).

The photo above is how Gerty arrived on the set a day before we began shooting in the Sarang facility set. As you can see, he is very clean and nice and has no graphics or dirtying down on him at all.
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I was worried that Gerty needed to look like he'd been around for fifteen years and also possibly beaten up and abused a bit through the course of living with Sam. I don't mean in a negligent way, just the same way a fifteen year-old computer might look if you dug it out of the garage and put it in your living room.
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I also put some ripped corners so it looked like this happened as routine and it occurred to me that I would probably draw on Gerty if I was living in the Sarang base. I'd also ride around on the robot arms and make them do bucking bronco type tricks when I got bored.

Varför GERTY (proppen) var faktiskt så smutsig behandlas detta också i samma intervju. Det korta svaret är att han är täckt av kaffegrund och har fått lim att göra det så att han är täckt av (nu borttagna) post-it-anteckningar.

So I ran off to grab a cup of coffee granules, added in a bit of boiling water to make it all mushy and started rubbing him down and putting some stray stickers on him whilst the first setup was being shot out in the greenhouse.
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When I was dirtying Gerty down at extremely high speed, I was trying to think about what my computers get like after I've had them for a couple of years. I tend to use post-it notes quite a lot and they inevitably end up being stuck all over my computers and monitor. I ran off to the production office and wrote down some notes that sounded like things Sam might not want to forget (such as servicing the boom on Rover 3), and just stuck them on him. Now it's all finished and up there on the screen it's a bit weird for me seeing my writing all over him.

Sir's robot looks a little clean...