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1.
This paper considers anti-windup design for linear systems subject to actuator saturation.Three anti-windup gains are designed for activations immediately at the occurrence actuator saturation,after the saturation has reached a certain level and in anticipation of the occurrence of saturation,respectively.The design is based on the minimization of L 2 gain from the disturbance to the controlled output of the resulting closed-loop system.Traditional anti-windup scheme involves a single anti-windup loop for immediate activation.A recent innovation is to design a single anti-windup loop for delayed or anticipatory activation,as well as to design two anti-windup gains,one for immediate activation and one for delayed activation.Our design of three anti-windup gains for three different activations is shown through simulation to lead to significant further performance improvement over the previous activation schemes.  相似文献   

2.
This paper attempts to set a unified scene for various linear time-invariant (LTI) control system design schemes, by transforming the existing concept of "computer-aided control system design" (CACSD) to novel "computer-automated control system design" (CAutoCSD). The first step towards this goal is to accommodate, under practical constraints, various design objectives that are desirable in both time and frequency domains. Such performance-prioritised unification is aimed at relieving practising engineers from having to select a particular control scheme and from sacrificing certain performance goals resulting from pre-commitment to such schemes. With recent progress in evolutionary computing based extra-numeric, multi-criterion search and optimisation techniques, such unification of LTI control schemes becomes feasible, analytical and practical, and the resultant designs can be creative. The techniques developed are applied to, and illustrated by, three design problems. The unified approach automatically provides an integrator for zero-steady state error in velocity control of a DC motor, and meets multiple objectives in the design of an LTI controller for a non-minimum phase plant and offers a high-performance LTI controller network for a non-linear chemical process.  相似文献   

3.
The development of new products of high quality, low unit cost, and short lead time to market are the key elements required for any enterprise to obtain a competitive advantage. For shorting the lead time to market and improving the creativity and performances of the product, a rule-based conceptual design approach and a methodology to simulate the conceptual design results generated in conceptual design process in automatical virtual entity form are presented in this paper. This part of paper presents a rule-based conceptual design method for generating creative conceptual design schemes of mechanisms based on Yan's kinematic chain regeneration creative design method. The design rules are adopted to describe the design requirements of the functional characteristics, the connection relationships and topological characteristics among mechanisms. Through the graphs-based reasoning process, the conceptual design space is expanded extremely, and the potential creative conceptual design results are then dug out. By refining the design rules, the solution exploration problem is avioded, and the tendentious conceptual design schemes are generated. Since mechanical, electrical and hydraulic subsystems can be transformed into general mechansims, the conceptual design method presented in this paper can also be applied in the conceptual design problem of complex mechatronic systems. And then the method to identify conceptual design schemes is given.  相似文献   

4.
In this paper,the per-layer design for Tomlinson-Harashima precoding (THP) in the downlink of multiuser multiple-input multiple-output (MIMO) systems is investigated.In these systems,the number of the receivers is equal to that of the transmit antennas.Based on the criterion of maximum system sum-capacity,we study two per-layer joint transmit and receive filters design schemes with receive antenna beamforming (RAB) and receive antenna selection (RAS),respectively.Moreover,the differences of the equivalent channel gains and capacities between these two schemes are analyzed theoretically.Simulation results show that by these per-layer schemes,the system sum-rate is improved significantly with respect to the per-user processing scheme.  相似文献   

5.
This paper focuses on a new finite-time convergence disturbance rejection control scheme design for a flexible Timoshenko manipulator subject to extraneous disturbances.To suppress the shear deformation and elastic oscillation,position the manipulator in a desired angle,and ensure the finitetime convergence of disturbances,we develop three disturbance observers(DOs)and boundary controllers.Under the derived DOs-based control schemes,the controlled system is guaranteed to be uniformly bounded stable and disturbance estimation errors converge to zero in a finite time.In the end,numerical simulations are established by finite difference methods to demonstrate the effectiveness of the devised scheme by selecting appropriate parameters.  相似文献   

6.
7.
介绍了采用MI200E电力线载波芯片设计路灯控制系统的思路,重点阐述了控制器模块与电力线载波模块的接口与硬件电路设计以及系统的软件设计。测试结果表明,该系统实现了路灯控制的良好运行与管理,性能稳定可靠。
Abstract:
This paper introduces the power line carrier chip of MI200E and the design of street lamps control system.It mainly discusses the interface of the controller module and power line carrier module,the design of hardware circuit and the software design of sy  相似文献   

8.
This paper addresses how to numerically solve the Hamilton-Jacobin-Isaac(HJI)equations derived from the robust receding horizon control schemes.The developed numerical method,the finite dierence scheme with sigmoidal transformation,is a stable and convergent algorithm for HJI equations.A boundary value iteration procedure is developed to increase the calculation accuracy with less time consumption.The obtained value function can be applied to the robust receding horizon controller design of some kind of uncertain nonlinear systems.In the controller design,the finite time horizon is extended into the infinite time horizon and the controller can be implemented in real time.It can avoid the on-line repeated optimization and the dependence on the feasibility of the initial state which are encountered in the traditional robust receding horizon control schemes.  相似文献   

9.
This paper investigates the robust graph coloring problem with application to a kind of examination timetabling by using the matrix semi-tensor product, and presents a number of new results and algorithms. First, using the matrix semi-tensor product, the robust graph coloring is expressed into a kind of optimization problem taking in an algebraic form of matrices, based on which an algorithm is designed to find all the most robust coloring schemes for any simple graph. Second, an equivalent problem of robust graph coloring is studied, and a necessary and sufficient condition is proposed, from which a new algorithm to find all the most robust coloring schemes is established. Third, a kind of examination timetabling is discussed by using the obtained results, and a method to design a practicable timetabling scheme is presented. Finally, the effectiveness of the results/algorithms presented in this paper is shown by two illustrative examples.  相似文献   

10.
11.
This work conducts robust Hanalysis for a class of quantum systems subject to perturbations in the interaction Hamiltonian.A necessary and sufficient condition for the robustly strict bounded real property of this type of uncertain quantum system is proposed.This paper focuses on the study of coherent robust Hcontroller design for quantum systems with uncertainties in the interaction Hamiltonian.The desired controller is connected with the uncertain quantum system through direct and indirect couplings.A necessary and sufficient condition is provided to build a connection between the robust Hcontrol problem and the scaled Hcontrol problem.A numerical procedure is provided to obtain coefficients of a coherent controller.An example is presented to illustrate the controller design method.  相似文献   

12.
Proxy signature is an active cryptographic research area, and a wide range of literatures can be found nowadays suggesting improvement and generalization of existing protocols in various directions. However, from the efficiency view, many proposed proxy signature schemes in these literatures are not satisfying and cannot fit to the mobile communication. Therefore, there is a desire to design efficient proxy signature schemes. Based on Boneh et al's pairing-based short signature, this paper presents two proxy signature schemes. One is proxy-protected signature scheme, and the other is proxy aggregate signature scheme. Since both of them can achieve high efficiency, it is believed that they are specially suitable for mobile communication environment.  相似文献   

13.
Although the design of many kinds of microprocessors has been under developing for several decades,the computer architecture R&D community lacks well documented lessons and experiences about design decisions in the research literature.In this paper,we systematically present the design decisions we made during the designing and prototyping of Godson-2 series processors.The 250MHz Godson-2B,450MHz Godson-2C,and 1GHz Godson-2E processors that implement 64-bit,four-issue,out-of-order architecture were taped out in 2003,2004,and 2005,respectively.Each processor triples its predecessor in the SPEC CPU2000 rates.Our first-hand experiences and lessons gained from these designs would provide unique perspectives and insights that are not available in any existing text books and/or published papers.We summarize 10 critical lessons and experiences based on hundreds of our attempts at architectural and design optimizations for performance improvement of Godson-2 series processors.The issues include silicon-simulation correlation,design balancing,performance optimizing,and pico-architecture tuning.We conclude that persistent improvement,attitude towards work-on-silicon design, and insightful understanding of software and fabrication process are the three most important factors for designing a high performance processor with low energy consumption.  相似文献   

14.
Integrated guidance and control for homing missiles utilizing adaptive dynamic surface control approach is considered based on the three channels independence design idea. A time-varying integrated guidance and control model with unmatched uncertainties is first formulated for the pitch channel, and an adaptive dynamic surface control algorithm is further developed to deal with these unmatched uncertainties. It is proved that the proposed feedback controller can ensure not only the accuracy of target interception, but also the stability of the missile dynamics. Then, the same control approach is further applied to the control design of the yaw and roll channels. The 6-degree-of-freedom (6-DOF) nonlinear missile simulation results demonstrate the feasibility and advantage of the proposed integrated guidance and control design scheme.  相似文献   

15.
We propose short group signature (GS) schemes which are provably secure without random oracles. Our basic scheme is about 14 times shorter than the Boyen-Waters GS scheme at Eurocrypt 2006, and 42% shorter than the recent GS schemes due to Ateniese et al. The security proofs are provided in the Universally Composable model, which allows the proofs of security valid not only when our scheme is executed in isolation, but also in composition with other secure cryptographic primitives. We also present several new computational assumptions and justify them in the generic group model. These assumptions are useful in the design of high-level protocols and may be of independent interest.  相似文献   

16.
This paper describes the design of guaranteed transient performance based attitude control for the near space vehicle(NSV)with control input saturation using the backstepping method.To improve the robust controllability of the NSV,the parameter adaptive method is used to tackle the integrated effect of unknown time-varying disturbance and control input saturation.Based on the backstepping technique and parameter estimated outputs,a robust attitude control scheme is proposed for the NSV with input saturation.A novel robust attitude control scheme is then proposed based on a prescribed performance bound(PPB)which characterizes the convergence rate and maximum overshoot of the attitude tracking error.The closed-loop system stability under both the developed robust attitude control schemes is proved using Lyapunov’s method and uniformly asymptotical convergence of all closed-loop signals is guaranteed.Finally,simulation results are given to show the effectiveness of both the proposed robust constrained attitude control schemes.  相似文献   

17.
This paper presents new results on the robust global stabilization and the gain assignment problems for stochastic nonlinear systems. Three stochastic nonlinear control design schemes are developed. Furthermore, a new stochastic gain assignment method is developed for a class of uncertain interconnected stochastic nonlinear systems. This method can be combined with the nonlinear small-gain theorem to design partial-state feedback controllers for stochastic nonlinear systems. Two numerical examples are given to illustrate the effectiveness of the proposed methodology.  相似文献   

18.
The existing E-government systems in China are always tight coupling, which are difficult to be replanted and adapted to the new EG business requirements. The paper schemes out an On-Demand architecture for E-government System. It discusses the process macro point of view. As for of the "On-Demand" design in macro Service On Demand (macro-SOD), it applies the theoretical thoughts of SOA (Service Oriented Architecture), that is "services oriented", into the encapsulation of system functional components. In the paper, we discuss the divisions and the main types of macro EG ser'Aces. The new system works more efficiently with characters of loose coupling, reusable components, dynamic application integration, dynamic workflow modeling and etc. The researching fruits will benefit the application theories of information system's design and solve the problems of existing EG systems.  相似文献   

19.
This research applied an open structure of generative design in order to provide parametric sliders for users to adjust a digital model under the designer's plan. Moreover, the design outcome can be printed immediately using 3D printing technology, to experiment with users' preferences and see the effects of generative design in modifying pattern, regular/irregular and detail transformations on a product. Three types of feature modification on iPhone4 case were chosen as simulations by three design experts. Five experienced and five young designers were asked to manipulate a digital generative design model as they want. Then 2D rendering images and 3D printed mockups were presented for subjects to compare with their original design. The result demonstrated that experienced and young designers both can recognized their work in 3D print mockups. Experienced designers can use the limited tool to make distinct outcomes for more satisfaction form tan subjects. Young designers expected to obtain 3D printed mockup to help their design decision in design process.  相似文献   

20.
COMPUTER AIDED PRELIMINARY DESIGN FOR ROTORS   总被引:1,自引:0,他引:1  
An interactive computer aided preliminary design system has been developed mainly for gasturbine engine rotors. The design system covers three parts: disks, shafts and rotor dynamics. A nu-merical optimization package called MPOP is used to minimize the weight of disks, shafts and optimizethe arrangement or stiffness of bearings for rigid or flexible rotors subjected to certain constraints ofsizes, shapes, stresses, deflections, stiffness and frequencies. Various forms of disks, shafts, rotorsand structure-analysing result curves are displayed on the screen. Designer may select, inspect or modi-fy the results interactively. The integrated design of structure, optimization, strength and rotor dynamics has improved designquality and reduced turnaround time during preliminary design phase of gas turbine engine develop-ment. As an example, a real preliminary design of an aeroengine turbine rotor is described.  相似文献   

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