This paper proposes a hybrid quasi-ARMAX modeling and identification scheme for nonlinear systems. The idea is to incorporate a group of certain nonlinear nonparametric models (NNMs) into a linear ARMAX structure. Par...
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ISBN:
(纸本)0780335902
This paper proposes a hybrid quasi-ARMAX modeling and identification scheme for nonlinear systems. The idea is to incorporate a group of certain nonlinear nonparametric models (NNMs) into a linear ARMAX structure. Particular effort is made to find a better compromise to the trade-off between the model flexibility and the simplicity for estimation by using knowledge information efficiently. As the result, we obtain a model equipped with a linear ARMAX structure, flexibility and simplicity. The effectiveness and usefulness of the proposed hybrid model are examined by applying it to identification and control of nonlinear systems.
This paper presents a robust fault detection system (FDS) for dynamic systems with unmodeled dynamics. In the FDS, umnodeled dynamics is first qualified as soft bound, which as well as model parameters are estimated u...
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This paper presents a robust fault detection system (FDS) for dynamic systems with unmodeled dynamics. In the FDS, umnodeled dynamics is first qualified as soft bound, which as well as model parameters are estimated using a robust identification algorithm. Then as a fault detection index, Kullback discrimination information (KDI) is derived into a feasible form and an index of umnodeled dynamics is also introduced. A decision making scheme is thus developed so that fault detection is carried out based on the KDI, the index of umnodeled dynamics and other prior information about the system.
This paper describes work in progress on two extensions to the environment of a Development Framework for the design of control system software; hybrid system design and design of dependable systems. The Development F...
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This paper describes work in progress on two extensions to the environment of a Development Framework for the design of control system software; hybrid system design and design of dependable systems. The Development Framework automatically converts a controlengineering specification into a parallel implementation. Hybrid controlsystems are a combination of real-time control law and discrete-state logic. The Framework can be adapted so that it may handle discrete events such as mode switching. A statechart tool, Statemate [i-Logix95], is used to specify and model discrete-state components. The design phase of the Development Framework supports the integration of the two sets of specification. Initial work to support the design of dependable systems has included the implementation of an interface between the Framework design model and the dependability modelling tool, SURF-2. Stochastic Petri net models of selected fault-tolerant mechanisms are currently supported. The models enable sensitivity analysis and comparison of competing architectures.
This paper deals with a digital adaptive control method for a manipulator mounted on a space robot after it captures an unknown object. Most control methods are based on the supposition that all physical parameters of...
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This paper deals with a digital adaptive control method for a manipulator mounted on a space robot after it captures an unknown object. Most control methods are based on the supposition that all physical parameters of the space robot are known. However, if the end-effector catches an unknown object, the physical parameters of the robot are changed, and the control performance deteriorates. In this paper, the authors propose two types of digital adaptive control algorithm using a discretized kinematic equation. computer simulation was used to make it clear that the control performance can be improved by using either of the proposed methods.
A robust internal force-based impedance control scheme for coordinating manipulators is introduced. Internal force-based impedance control enforces a relationship between the velocity of each manipulator and the inter...
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A robust internal force-based impedance control scheme for coordinating manipulators is introduced. Internal force-based impedance control enforces a relationship between the velocity of each manipulator and the internal force on the manipulated objects and requires no knowledge of the object dynamic model. Each manipulator's nonlinear dynamics is compensated by a robust auxiliary controller which is insensitive to robot-model uncertainty and payload variation. The controller is only weakly-dependent on each manipulator's inertia matrix. Stability of the system is analyzed. The scheme is computationally inexpensive and suitable for general-purpose microcomputer implementation. Rigorous experimental investigations are performed and the results presented which validate the proposed concepts.
A fundamental limitation in achieving high performance control for multivariable plants is associated with the operating range of the control input signals associated with the plant, i.e. in order to design realistic ...
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A fundamental limitation in achieving high performance control for multivariable plants is associated with the operating range of the control input signals associated with the plant, i.e. in order to design realistic controllers for a plant, it is essential to take into account control signal saturation effects. This paper describes various classes of controllers for a LTI plant, which have the property that they solve the robust, servomechanism problem for constant tracking/disturbance signals, and maximize the operating range of the controllers for the plant . Some application studies re the control of a distillation column with pressure variation are included to illustrate the behaviour of the controllers.
作者：
R.G. BonitzT.C. HsiaSystems
Control and Robotics Laboratory Department of Electrical and Computer Engineering University of California Los Angeles Davis CA USA
An internal force-based impedance control scheme for two coordinating robots manipulating a rigid object via palm grasping is introduced. The minimal internal force required to maintain the grasp on the object is comp...
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An internal force-based impedance control scheme for two coordinating robots manipulating a rigid object via palm grasping is introduced. The minimal internal force required to maintain the grasp on the object is computed from the frictional constraints and sensed forces. A closed-form solution to the minimization problem is developed which makes the algorithm suitable for real-time control. The controller uses sensed moments at the palm interface to maintain proper orientation of the palms to achieve maximum surface contact. Each manipulator's nonlinear dynamics is compensated by a robust auxiliary controller which is insensitive to robot-model uncertainty and payload variation. The controller is only weakly-dependent on each manipulator's inertia matrix. Stability of the system is analyzed. Rigorous experimental investigations are are performed and the results presented which validate the proposed concepts.
We consider a special discrete-time hybrid problem: the plant state "lives" in IRn and is affected by real-valued norm-bounded disturbances;the control input and measurement signals are sequences of symbols....
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This paper presents an investigation into tne nature ot control algorithms in relation to that of the architectures for real-time applications so that a close match be forged between them. Several algorithms of regula...
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This paper presents an investigation into tne nature ot control algorithms in relation to that of the architectures for real-time applications so that a close match be forged between them. Several algorithms of regular and irregular nature are implemented on a number of architectures possessing different features. Partitioning and mapping of the algorithms, algorithm regularity and hardware and algorithm granularity are addressed in implementing the algorithms on parallel architectures. A comparison of the results of implementations is made to establish merits of the development of parallel architectures for real-time applications. Finally, the potential of heterogeneous architectures in real-time applications has been justified by the development of a three-node architecture and its performance verification in comparison to uni-processor and two-node homogeneous and heterogeneous architectures.
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