On global controllability of planar affine nonlinear systems with a singularity

This paper is concerned with the global controllability of planar affine nonlinear systems with a singular point. By using some recent developed methods, a necessary and sufficient condition is obtained, which can also be viewed as a generalization of the corresponding result in the book by Nikitin [S. Nikitin, Global Controllability and Stabilization of Nonlinear Systems, World Scientific Publishing Co. Pte. Ltd., Singapore, 1994].