ISSN:0020-7179    

DOI:10.1080/00207179308934426

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In this paper, compensator dynamics are introduced in sliding mode through a new class of switching surfaces which has the interpretation of linear operators. Two design methods are presented, the first is based on pole placement, whereas the second is based on frequency-shaped quadratic optimal control formulation. The compensators are designed to attenuate the frequency contents of the sliding mode dynamics such that unmodelled dynamics are minimally excited. The design method using frequency shaping is applied to the control of a flexible link robot arm. Simulation results show that the excitation of the link deformations are minimized while preserving the insensitivity of the sliding mode.

ISSN:0020-7179    

DOI:10.1080/00207179308934427

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The design of the sliding hyperplanes of a variable structure control system is an important part of the controller design process, and will be considered in this paper. The method outlined here results in the eigenvalues of the closed-loop system during sliding lying in a specified sector in the left-hand half-plane. Numerical examples are given, and the effect of an arbitrary positive definite matrix in a complex Riccati equation on the positioning of the eigenvalues within the sector, is investigated.

ISSN:0020-7179    

DOI:10.1080/00207179308934428

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The consequences of the differential algebraic approach in the sliding mode control of nonlinear single-input single-output systems are reviewed in tutorial fashion. Input-dependent sliding surfaces, possibly including time derivatives of the input signal, are shown to arise naturally from elementary differential algebraic results pertaining to the Fliess's Generalized Controller Canonical Forms of nonlinear systems. This class of switching surfaces generally leads to chattering-free dynamically synthesized sliding regimes, in which the highest time derivative of the input signal undergoes all the bang-bang type discontinuities. Examples illustrating the obtained results are also included.

ISSN:0020-7179    

DOI:10.1080/00207179308934429

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In this paper, a possible merge between the theory of variable structure control systems and that of model reference adaptive control is presented with reference to a pole assignment control problem in the presence of uncertain non-minimum phase systems affected by bounded disturbances. The control scheme proposed is characterized by a simple first-order fixed compensator introduced in parallel to the plant, so that the parallel connection turns out to be a relative-degree-one system with a not necessarily Hurwitz numerator, by a set of tunable state variable filters, along with an all-pass filter which allows us to avoid any unstable pole-zero cancellation in the presence of a non-Hurwitz plant numerator. By applying discontinuous control actions with an all-pass filter, it is possible to force a signal, which plays the role of output error, to zero, keeping the amplitude of all the control signals bounded, and solving a pole assignment problem. The main novelty of this work consists in the analysis of the case in which a bounded disturbance affects the plant behaviour. The rejection of the disturbance is proved by using Filippov's solution concept, after showing that the equivalent bounded control continuous system which describes the behaviour of the plant on the sliding manifold is unique.

ISSN:0020-7179    

DOI:10.1080/00207179308934430

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

This paper deals with the robust stabilization of continuous-time dynamical systems in the presence of parametric and external time-varying disturbances. Modified Variable Structure control algorithms with additional integral terms are considered here and analysed. A comparison with a typical ‘static’ VS algorithm is made. Static VS algorithms can reject completely the disturbance only if the amplitude of the switching term, in the control input, is larger than the amplitude of the disturbance itself. This paper shows how it is possible, by adding an integral term in the VS control algorithm, to reach and remain in the sliding mode if the amplitude of the switching term is smaller than the amplitude of the disturbance. Some simulations supporting the theoretical results are reported and discussed.

ISSN:0020-7179    

DOI:10.1080/00207179308934431

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

We present new results on the output control of uncertain dynamical systems. The design method uses dynamical compensators to turn the compensated plant into a strictly positive real system, and then chooses the control law—for example, a sliding mode control. This result is compared with another result from the literature which uses static compensators. An example is presented where the control with dynamic compensation works while a static compensation does not.

ISSN:0020-7179    

DOI:10.1080/00207179308934432

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

It is well known that sliding mode control schemes provide robustness to the class of uncertainty acting within channels implicit in the control inputs: the so-called matched uncertainty. However, the unmatched uncertainty will affect the ideal dynamics prescribed by the chosen switching surfaces. This paper develops a control strategy to minimize the effects of the unmatched uncertainty upon the dynamic performance prescribed by the switching surfaces. This is achieved for a subclass of the uncertainty class considered by previous authors. The practical application of the control strategy to the design of a stability augmentation system for a light aircraft is presented. For this problem an ideal performance is well known and it is desirable that these ideal dynamics are exhibited across a wide range of flight conditions without degradation.

ISSN:0020-7179    

DOI:10.1080/00207179308934433

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The problem is considered of sliding mode synthesis along discontinuity surfaces. The design approach is based on the unit control method under uncertainty conditions and the maximization of control efficiency. The results obtained concern both continuous- and discrete-time systems.

ISSN:0020-7179    

DOI:10.1080/00207179308934434

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

To make input-output feedback linearization a practical and systematic design methodology for single-input nonlinear systems, two problems need to be addressed. One is to handle systematically the difficulties associated with the internal dynamics or zero-dynamics when the relative degree is less than the system order. The other is to account for the effect of model uncertainties in the successive differentiations of the output of interest. While the first problem has recently received considerable attention, the second has been largely unexplored. This paper represents a preliminary study of a systematic methodology to account robustly for parametric uncertainties in the original system model. The approach is based on combining sliding control ideas with the recursive construction of a closed-loop Lyapunov function, and is illustrated with a simple example.

ISSN:0020-7179    

DOI:10.1080/00207179308934435

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor