This circa 1939 plan for a robotic dog on
Mostly Forbidden Zone piqued my interest. I did a little digging and found an interesting story behind it. The Scottish Terrier, named Sparko, was designed by Westinghouse engineer, Joseph Barnett, to stimulate interest in their electrical products. The dog was the pet of a larger human-type robot named Elektro and was able to sit up, wag his tail and do various other dog tricks on command. Three Sparkos were made but none remain today.
The last confirmed sighting of Sparko was in California in 1957. The dogs were light-followers and legend has it that one of the three dogs was hit by a car and destroyed when it wandered out of an open door at the Westingouse lab.
http://liftlab.com/think/nova/2008/02/18/sparko-the-robotic-scottish-terrier/
I'd entirely forgotten his story until seeing this post. He passed away in 1995 so there isn't any way to get more information about it.