Analog robot
An analog robot is a type of robot which uses analog circuitry to go toward a simple goal such as finding more light or responding to sound. The first real analog robot was invented in the 1940s by William Grey Walter. The name of these robots were ELSIE and ELMER (Electro Mechanical Robot). The original circuitry was developed using two vacuum tubes and a photocell to search and follow a light. Recently a kind of analog robots was developed by Mark Tilden.
Zadoc Dederick
Zadoc P. Dederick was an American inventor. Along with Isaac Grass he was the creator of a steam-powered humanlike robot designed to pull a cart. The invention was patented on March 24, 1868, as patent 75874, and operated through a system of levers and cranks, attached to steam-powered pistons and a boiler. The original prototype cost $2000 (about $32,487 in modern US dollars) and was built in Newark, New Jersey. Plans to produce it for $300 never went through, making this an example of an early development in steam power that was abandoned. Nonetheless, inventions such as this one spurred interest in steam power, as exemplified by novels such as "The Steam Man of the Prairies", and by many imitations and hoaxes that appeared as a result.