In the early ‘60s, as part of the preparations for the Apollo manned moon landing mission, the Jet Propulsion Lab planned a follow-on program to its very successful ‘hard’ landing ‘Ranger’ program, which gave the first close-up views of the moon’s surface. The proposed ‘soft’ lander program was called ‘Surveyor’. An initial concept was for it to disgorge a moon surface-traversing vehicle to conduct a neighborhood survey near its landing position. It was to be commanded by a TV – radio control guidance link. This link was to be relayed to and from the moon via the Surveyor’s earth communication system. A lunar rover competition was opened and by end of 1961 there were responses from at least 10 leading space firms including Space-General Corp., Sperry Rand, and RCA.
When it was determined that the Atlas rockets could not lift the Surveyor with an added payload of a Lunar Rover, the project was discontinued.
From RCA's Astro-Electronics Division, Defence Electronics Products.
"Porky the Pig" (also "Porkie") most likely propelled itself forward or backward by raising the two larger inside legs as one, then following up with raising the other 4 legs and moving in the desired direction. Steering could be effected by using a twisting motion of the inside legs before they are lowered.