Notes on geometric algebras in geometric control theory (sub-Riemannian geometry) Jaroslav Hrdina -- Brno University of Technology In a sub-Riemannian space we can neither move nor send information in all the directions, nor can we receive information from everywhere. There are constraints (imposed by God, by a moral imperative, by a government, or just by the laws of Nature). We study the role of geometric algebras in sub-Riemannian space. We mainly discuss control problems on free Carnot groups of step $2$, specially Heisenberg group.