Shakey, the first mobile robot that reasons

Shakey was a wheeled cabinet with a television camera, a rangefinder and bump sensors, connected by radio to an SDS 940 computer that filled a room. The project started at the Stanford Research Institute in 1966 and ran until 1972, and its point was to make a robot that did not just move but decided. Given a goal such as pushing a block off a platform, Shakey built a plan in first-order logic, executed it, and replanned when the world did not match.

To find routes it needed a search algorithm that was both fast and guaranteed to find the shortest path, and in 1968 Peter Hart, Nils Nilsson and Bertram Raphael published A*, which combines the cost so far with an estimate of the cost to go. A* is in every satnav, every game and most planning systems since. The STRIPS planner written for Shakey in 1971 defined how AI represented actions for the next thirty years.

Shakey took hours to cross a room and the project was cancelled in 1972 during the funding review that preceded the first winter. The research programme it began, robots that perceive, plan and act, is the one the humanoid companies of the 2020s are still running.