Stabilizing Lexicographic NMPC without terminal constraints

In many control applications, cost criteria generally have multiple conflicting performance objectives which span different levels of relative importance. In this paper, we present a new multi-objective model predictive control (MO-MPC) strategy of nonlinear systems subject to constraints and objectives prioritization. Based on the MO-MPC with lexicographic optimization, the new lexicographic NMPC strategy without terminal constraint is designed. The computational burden of online solving the optimization problem can be reduced. Some sufficient conditions are derived to guarantee the feasibility and stability properties of the new MO-NMPC. The multi-objective control problem of a coupled-tank system is used to illustrate the effectiveness of the proposed MO-NMPC strategy.