2020 年 56 巻 5 号 p. 259-268
We consider input-to-state-stability gain (ISS-gain) design for a differentially flat system disturbed by bounded noise. Firstly, we design a C∞ differential strict control Lyapunov function (CLF) for the augmented linear system on the extended state space. The CLF satisfies predetermined L2 norms performance by solving state feedback H∞ control problems to attenuate persistent disturbance levels. Then, an Input-state-stability CLF (ISS-CLF) is derived from the CLF by applying a dynamic extension method and a minimum projection method. The ISS-CLF and the predetermined L2 norms performance give the analytic ISS gain function. Finally, we specify the L2 norms performance bounds of the disturbance attenuation controller for the differentially flat system. The effectiveness of the proposed method is confirmed by computer simulation of marine vessel control.