Nils John Nilsson (February 6, 1933 – April 23, 2019) was an American computer scientist. He was one of the founding researchers in the discipline of artificial intelligence. He was the first Kumagai Professor of Engineering in computer science at Stanford University from 1991 until his retirement. He is particularly known for his contributions to search, planning, knowledge representation, and robotics.
Nilsson was born in Saginaw, Michigan, in 1933. He received his Ph.D. from Stanford in 1958, and spent much of his career at SRI International, a private research lab spun off from Stanford.
Nilsson served as a lieutenant in the U.S. Air Force from 1958 to 1961; he was stationed at the Rome Air Development Center in Rome, New York.
Starting in 1966, Nilsson, along with Charles A. Rosen and Bertram Raphael, led a research team in the construction of Shakey, a robot that constructed a model of its environment from sensor data, reasoned about that environment to arrive at a plan of action, then carried that plan out by sending commands to its motors. This paradigm has been enormously influential in AI. Textbooks such as Introduction to Artificial Intelligence, Essentials of Artificial Intelligence, and the first edition of Artificial Intelligence: A Modern Approach show this influence in almost every chapter. Although the basic idea of using logical reasoning to decide on actions is due to John McCarthy, Nilsson's group was the first to embody it in a complete agent, along the way inventing the A* search algorithm and founding the field of automated temporal planning. In the latter pursuit, they invented the STRIPS planner, whose action representation is still the basis of many of today's planning algorithms. The subfield of automated temporal planning called classical planning is based on most of the assumptions built into STRIPS.
In 1985, Nilsson became a faculty member at Stanford University, in the Computer Science Department. He was chair of the department from 1985 to 1990.