文摘
Singular curves, which are projections of singular extremals, play a special role in control theory and the theory of distributions. In this paper, we show that singular velocities, tangent to singular curves, determine affine distributions that are simultaneously of an even-rank and co-rank 2. If D is such a distribution, then its singular velocities span a distribution C D (of a rank two times smaller than that of D) that, together with its Lie square, forms the initial distribution, i.e., \(D={C^{D}}+\left [{C^{D}},{C^{D}}\right ]\) . We also provide canonical constructions of vector fields that are C D generators, canonical differential forms that are D cogenerators, and some functional invariants related to distribution of the considered type.