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The development of ''Non-Uniform Rational B-Spline'' (NURBS)originated with seminal work at [[Boeing]] and [[SDRC]] (Structural Dynamics Research Corporation) in the 1980s and '90s, a company that led in mechanical computer-aided engineering in those years.<ref>[http://isicad.net/articles.php?article_num=14940 "NURBS and CAD: 30 Years Together"], Ushakov, Dmitry, isicad, December 30, 2011.</ref> Boeing's involvement in NURBS dates back to 1979, when they began developing their own comprehensive CAD/CAM system, TIGER, to support the diverse needs of their aircraft and aerospace engineering groups. Three basic decisions were critical to establishing an environment conducive to developing NURBS. The first was Boeing's need to develop its own in-house geometry capability. Specifically, Boeing had complex surface geometry needs, especially for wing design, that could not be found in any commercially available [[CAD/CAM]] system. As a result, the TIGER Geometry Development Group was established in 1979 and has received strong support for many years. The second decision critical to NURBS development was the removing the constraint of upward geometrical compatibility with the two systems used at Boeing at that time. One of these systems had evolved due to the iterative process inherent to wing design, while the other was best suited for adding to the constraints imposed by manufacturing, such as cylindrical and planar regions. The third crucial decision was simple but essential: adding the "R" to "NURBS." Circles were to be represented precisely, with no cubic approximations allowed.
By late 1979, there were
By early 1980, the staff were busy choosing curve representations and developing the geometry algorithms for TIGER. One of the major tasks was curve/curve intersection. It
With this motivation, the staff started down the road toward what became NURBS. The design of a wing demands free-form, C2 continuous, cubic splines to satisfy the needs of aerodynamic analysis, yet the circle and cylinders of manufacturing require at least rational Bézier curves. The properties of Bézier curves and uniform B-splines were well known, but the staff had to gain an understanding of non-uniform B-splines and rational Bézier curves and try to integrate the two. It was necessary to convert circles and other conics to rational Bézier curves for the curve/curve intersection. At the time, none of the staff realized the importance of the work, and it was considered "too trivial" and "nothing new". The transition from uniform to non-uniform B-splines was rather straight forward, since the mathematical foundation had been available in the literature for many years. It just had not yet become a part of standard CAD/CAM applied mathematics.
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