This paper discusses computational issues in kinematic design of tac- tile sensing xtures used in robotics applications. It deals with mechanical xtures built or modeled by feature surfaces consisting of planes, spheres, and cylinders. It develops the governing equations for locating each of these geometric objects using tactile sensing probes. It shows that although four points are needed to locate a sphere, in many applications sensing three points is sucient for referencing. In the case of a cylinder it is shown that in general six points are necessary and that in many applications ve points are sucient for locating the cylinder. The paper reduces the governing equations for a cylinder to a set of polynomial equations consisting of a second-degree and a third-degree equation. The solutions of this set are found using symbolic computations. The results are applied to the kinematic design and analysis of a mechanical xture consisting of a sphere and a cylinder as its feature surfaces.