The problem of output regulation of affine nonlinear systems with the relative degree not well defined by modified steepest descent control is studied. The modified steepest descent control is a dynamic feedback control which is generated by the trajectory following method. By assuming the system is minimum phase, output of the system can be regulated globally asymptotically.

This paper deals with a discrete time repetitive control synthesis for non minimum phase plants. Two parts can be distinguished. The main design features of the repetitive controllers are discussed in the first part. More precisely one shows that one can realize two objectives; tracking with zero error and tracking with nonzero error. In the second part, a suitable plant model identification pr...

This paper addresses the global asymptotic stabilization of nonlinear systems in the presence of unmodeled dynamics appearing at the input. The unmodeled dynamics are restricted to be minimum-phase and relative degree zero. On the basis of nonlinear small-gain arguments, we design a static feedback control law to achieve global asymptotic stabilization. In the absence of full state information ...

We consider the problem of output regulation for the class of minimum-phase nonlinear systems described in normal form. We assume that the ideal steady state control input fulfills a nonlinear regression law that is linearly parametrized in the uncertain parameters and we propose an internal model-based design that combines high-gain and identification tools. The identification tool by which th...

This paper presents a new approach towards the design of iterative learning control (Moore, 1993). In linear motion control systems the design is often complicated by the inverse plant sensitivity being non-causal and even unstable. To overcome these problems the inverse system is split up in a causal and a non-causal part. We apply high-performance differentiating filters together with a mixed...

A control design to stabilise a reduced scale autonomous helicopter equipped with a camera is presented. The proposed algorithm is motivated by recent work in image-based visual servoing control for under-actuated dynamic systems. This work is extended by considering models that contain weakly nonminimum phase zero dynamics. This is an important class of systems since an o set between the camer...

-There has been a great deal of excitement recently over the development of a theory for explicitly linearizing the input-output response of a nonlinear system using state feedback. One shortcoming of this theory is the inability to deal with non-minimum phase nonlinear systems. Highly maneuverable jet aircraft, such as the V/STOL Harrier, belong to an important class of a slightly non-minimum ...

In this paper it is explored whether or not a well-known adjoint Iterative Learning Control (ILC) algorithm can be applied to Repetitive Control (RC) problems. It is found that due to the lack of resetting in Repetitive Control, and the non-causal nature of the adjoint algorithm, the implementation requires a truncation procedure that can lead to instability. In order to avoid the truncation pr...

Fundamental limitations in decentralized control of systems with multivariable zeros are considered. It is shown that arbitrary bandwidth can be obtained with a stable block-diagonal controller, if certain subsystems of the open-loop system fail to have zeros in the right half-plane and a high-frequency condition holds. Implications on control structure design and sequential loop-closuring meth...

In the present paper, we examine model feedback control systems. Because model feedback control is simple, the model feedback control system has been applied in many applications such as the trajectory control of robot manipulators, serially connected tanks, etc. The control structure of the model feedback control system is limited, and nothing has been reported about whether or not model feedb...