This could easily bring in a plethora of other thoughts but...

what is pain except that it's a signal sent by the nerves to the brain which are interpreted and some kind of standard reaction results.

It's possible now for a computer to be equipped with the proper sensors and programmed to respond in a certain fashion (eg., move away from where the "pain" occurred).

I see no difference between "acting" as if it feels pain, and feeling pain. The stimuli, process, and result are the same.