- Author
-
McGee, L. A.
|
Schmidt, S. F.
- Title
- Discovery of the Kalman Filter as a Practical Tool for Aerospace and Industry. Technical Memorandum.
- Coporate
- Ames Research Center, Moffett Field, CA
- Sponsor
- National Aeronautics and Space Admin., Washington, DC
- Report
-
NASA TM-86847,
November 1985,
24 p.
- Distribution
- Available from National Technical Information Service
- Keywords
-
filters
|
spacecraft
|
aerospace safety
|
airborne computers
|
flight tests
- Identifiers
- Kalman filter; state-estimation; navigation; square-root filter
- Abstract
- The Kalman filter in its various forms has become a fundamental tool for analyzing and solving a broad class of estimation problems. The first publicly known application was made at NASA Ames Research Center in the early 1960s during feasibility studies for circumlinear navigation and control of the Apollo space capsule. This paper recounts the fortunate sequence of events which led the researchers at Ames Research Center to the early discovery of the Kalman filter shortly after its introduction into the literature. The scientific breakthroughs and reformulations that were necessary to transform Kalman's work into a useful tool for a specific aerospace application are described. The resulting extended Kalman filter, as it is now know, is often still referred to simply as the Kalman filter. As the filter's use gained in popularity in the scientific community, the problems of implementaion on small spaceborne and airborne computers led to a "square-root" formulation of the filter to overcome numerical difficulties associated with computer word length. The work that led to this new formulation is also discussed, including the first airborne computer implementation and flight test which was conducted in 1972. Since then the applications of the extended and square-roof formulations of the Kalman filter have grown rapidly throughout the aerospace industry.