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.
History of artificial life
Automatons were quite a novelty. In the days before computers and electronics, some were very sophisticated, using pneumatics, mechanics, and hydraulics. The first automata were conceived during the third and second centuries BC and these were demonstrated by the theorems of Hero of Alexandria, which included sophisticated mechanical and hydraulic solutions. Many of his notable works were included in the book "Pneumatics", which was also used for constructing machines until early modern times. In 1490, Leonardo Da Vinci also constructed an armored knight, which is considered the first humanoid robot in Western civilization.