A worst-case evaluation method for dynamic systems

A worst-case evaluation method is presented in this paper. The objective of this method is to identify worst-case disturbances so that the performance of dynamic systems under extreme conditions can be evaluated Depending on the dynamics and information structure of the system, the worst-case evalua tion problems ave classified into four cases. Classical optimal control and game theories are used to construct algorithms to obtain linear solutions analytically. Numerical schemes to solve nonlinear worst-case problems are also presented. Two case study examples are then presented-a truck rollover problem and a vehicle stability controller evaluation problem. In both cas es, a combined analytical-numerical method is used. The nonlinear plant is first linearised. The analytical solution of the linearized plant is then u sed as the initial guess for the numerical scheme. The final worst-case dis turbance is then obtained iteratively from the numerical scheme. It was fou nd that the proposed worst-case evaluation method is able to produce much l arger unwanted plant motions (roll/side slip in the two case studies) compa red with traditional evaluation maneuvers.