Control analysis and synthesis for general control-affine systems

Abstract: This paper provides controllability analysis and control synthesis for general control-affine systems, potentially subject to a bounded perturbation. We establish sufficient controllability conditions based on a proper generalization of the controllability Gramian for linear systems. Under these sufficient conditions, control syntheses are developed. We provide two control input constructions for a given system, either of which can steer the system from a given initial state to any desired target state within a finite time horizon. As in our analysis, in the case of linearity, these syntheses are reduced to common control inputs based on the controllability of Gramian. Additionally, we derive a sharp upper bound on the $L^2$-norm of these control functions, allowing us to derive insights into the energy required to enact control. The work advances the theory of nonlinear controllability and provides an analytical framework that facilitates numerical verification and practical implementation.