While robust estimators have been used in a variety of computer vision applications, three are considered here. In each case, a straightforward application of standard robust estimators is insufficient, and carefully developed extensions are used to solve the problem. The developments are applicable to other problem-solving environments and some are applicable to general scientific computation. A computable test for this new version of controllability is derived. This condition involves an object that we call the symmetric product.
Examples illustrate the theory.
For the derivations, the computer algebra system Maple is used.