检索结果-内蒙古大学图书馆

Discussion: “Effect of control algorithms on Magnetic Journal Bearing Properties” (Humphris, R. R., Kelm, R. D., Lewis, D. W., and Allaire, P. E., 1986, ASME J. Eng. Gas Turbines Power, 108, pp. 624–632)

引用

Journal of Engineering for Gas Turbines and Power 1987年第3期109卷 353页

作者： Burrows, C. R. University of Strathclyde Glasgow United Kingdom

来源：评论

学校读者我要写书评

暂无评论

OPTIMAL-control OF NONLINEAR STRUCTURES

引用

JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME 1988年第4期55卷 931-938页

作者： YANG, JN LONG, FX WONG, D GEORGE WASHINGTON UNIV DEPT CIVIL MECH & ENVIRONM ENGNWASHINGTONDC 20052

Three optimal control algorithms are proposed for reducing oscillations of flexible nonlinear structures subjected to general stochastic dynamic loads, such as earthquakes, waves, winds, etc. The optimal control forces are determined analytically by minimizing a time-dependent quadratic performance index, and nonlinear equations of motion are solved using the Wilson-θ numerical procedures. The optimal control algorithms developed for applications to nonlinear structures are referred to as the instantaneous optimal control algorithms, including the instantaneous optimal open-loop control algorithm, instantaneous optimal closed-loop control algorithm, and instantaneous optimal closed-open-loop control algorithm. These optimal algorithms are computationally efficient and suitable for on-line implementation of active control systems to realistic nonlinear structures. Numerical examples are worked out to demonstrate the applications of these optimal control algorithms to nonlinear structures. In particular, control of structures undergoing inelastic deformations under strong earthquake excitations are illustrated. The advantage of using combined passive/active control systems is also demonstrated.

关键词： Optimal control algorithms control algorithms Earthquakes control systems Motion Stress Waves Nonlinear equations Oscillations

来源：评论

学校读者我要写书评

暂无评论

EFFECT OF control algorithms ON MAGNETIC JOURNAL BEARING PROPERTIES

引用

JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME 1986年第4期108卷 624-632页

作者： HUMPHRIS, RR KELM, RD LEWIS, DW ALLAIRE, PE R. R. Humphris R. D. Kelm D. W. Lewis P. E. Allaire Department of Mechanical and Aerospace Engineering University of Virginia Charlottesville VA 22901

Magnetic journal bearings are coming into increasing use in industry today. They are primarily used to replace either rolling element or fluid film bearings in rotating machinery. The major advantages are elimination of oil systems and associated seals, expected very long life, very low power losses, and great potential for vibration reduction. Disadvantages include lack of field experience, unknown reliability over a long time, high cost (so far primarily due to the small quantity being made for a given application), and advanced automatic control design required. This paper discusses the design of a magnetic journal bearing with four electromagnets arranged radially around a shaft to fully support a rotor. Each electromagnetic is connected to a controlling electronics circuit which regulates the current to the magnet. For the measurements presented here, only the top magnet was tested and the shaft was not rotating. Thus a single control algorithm was isolated from other effects. This paper compares two control algorithms with differing circuit band widths of 1.2 kHz and 50 kHz. The wider bandwidth algorithm produced approximately a sixfold increase in magnetic bearing stiffness and a much greater stable operating region compared to the lower bandwidth algorithm. Overall, the calculated effective stiffness and damping coefficients were within 20 to 30 percent of the measured values.

关键词： Journal bearings control algorithms Stiffness Circuits Magnets algorithms Design Rotors Vibration Bearings

来源：评论

学校读者我要写书评

暂无评论

MODELING OF A MID-SIZE PASSENGER CAR USING A MULTIBODY DYNAMICS PROGRAM

引用

JOURNAL OF MECHANISMS TRANSMISSIONS AND AUTOMATION IN DESIGN-TRANSACTIONS OF THE ASME 1987年第4期109卷 518-523页

作者： TROM, JD LOPEZ, JL VANDERPLOEG, MJ Iowa State University Delco Products Division General Motors Corporation

This paper presents a multibody model of a passenger car and correlates the model with experimental data. Included in the model is a simple load-leveling control algorithm for controlling low frequency roll and pitch. The objectives of this paper are: to evaluate the effectiveness of vehicle modeling using a multibody dynamics program; to demonstrate multibody modeling techniques for complex suspension systems without the use of bushing models; and to demonstrate the feasibility of implementing control algorithms in multibody dynamics programs. The paper concludes that using multibody dynamics programs can be an effective method to model ride, handling, and braking of wheeled vehicles. The model presented in this paper shows good correlation in both the linear and nonlinear ranges for most maneuvers.

关键词： Braking Bushings Vehicles Stress control algorithms Modeling Automobiles Multibody dynamics Suspension systems

来源：评论

学校读者我要写书评

暂无评论

REAL-TIME POWER-SYSTEM SIMULATION

引用

IEE PROCEEDINGS-C GENERATION TRANSMISSION AND DISTRIBUTION 1987年第3期134卷 206-223页

作者： RAFIAN, M STERLING, MJH IRVING, MR UNIV DURHAM SCH ENGN & APPL SCIDURHAM DH1 3LEENGLAND

This paper describes the theoretical basis and application of a simulation package for electrical generation, transmission and distribution systems. The software provides an environment for the development and testing of online analysis and control algorithms, and also has potential for application in operator training. Dynamic and algebraic models of power system elements are described which are appropriate for study time scales of up to one day. Numerical techniques are presented which obtain solutions with acceptable accuracy in real time for medium sized networks using minicomputer hardware. Typical results are given for a test network of 30 substations which illustrate the dynamic behaviour of the network under emergency conditions.

关键词： real time distribution systems control algorithms dynamic models online analysis simulation package power system simulation emergency conditions electrical generation algebraic models power system analysis computing Power engineering computing minicomputer hardware operator training real-time systems digital simulation transmission Power system management, operation and economics

来源：评论

学校读者我要写书评

暂无评论

NEAR-OPTIMAL control OF A BILINEAR, SOLAR-ASSISTED HEAT-PUMP SYSTEM

引用

JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME 1987年第4期109卷 259-266页

作者： LE, H ZAHEERUDDIN, M GOURISHANKAR, V RINK, R UNIV ALBERTA DEPT ELECT ENGNEDMONTON T6G 2E1ALBERTACANADA

A system consisting of a flat-plate solar collector, two heat storage tanks, a heat pump, and all necessary minor components is considered. For each major component a bilinear mathematical model is developed. The system control problem is divided into steady-state and dynamic cases, and the optimal steady-state solution is found. Based on this result a suboptimal dynamic control algorithm is given and is shown to give locally stable and near optimal performance. Results of a simulation study, comparing seasonal performance of the suboptimal system with that of the conventionally-controlled system are given.

关键词： Solar energy Heat pumps Steady state control algorithms Flat plates Heat storage Simulation Solar collectors

来源：评论

学校读者我要写书评

暂无评论

MOTION control ANALYSIS OF A MOBILE ROBOT

引用

JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1987年第2期109卷 73-79页

作者： BORENSTEIN, J KOREN, Y UNIV MICHIGAN DEPT MECH ENGN & APPL MECH ANN ARBOR MI 48109 USA

A computer-controlled vehicle that is part of a mobile nursing robot system is described. The vehicle applies a motion control strategy that attempts to avoid slippage and minimize position errors. A cross-coupling control algorithm that guarantees a zero steady-state orientation error (assuming no slippage) is proposed and a stability analysis of the control system is presented. Results of experiments performed on a prototype vehicle verify the theoretical analysis.

关键词： Motion control Mobile robots Vehicles Errors Computers Steady state Theoretical analysis control algorithms Engineering prototypes Stability

来源：评论

学校读者我要写书评

暂无评论

NONLINEAR control OF A DISTRIBUTED SYSTEM - SIMULATION AND EXPERIMENTAL RESULTS

引用

JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1987年第2期109卷 133-139页

作者： PLUMP, JM HUBBARD, JE BAILEY, T CHARLES STARK DRAPER LAB INC CAMBRIDGEMA 02139

A nonlinear active vibration damper has been developed which uses a spatially distributed piezoelectric actuator, polyvinylidene flouride, to achieve active vibration control of a cantilever beam. The control algorithm was derived using Lyapunov’s Second Method. All modes of the beam can be controlled simultaneously if the angular velocity of the tip of the beam is known. A simulation algorithm was developed to predict the effect of the control on the free decay of a single mode. A parameter study for the first mode was performed and compared to experimental results. The active damper has been tested successfully on two different scale structures.

关键词： Simulation Vibration dampers Vibration control algorithms Dampers Piezoelectric actuators control algorithms Cantilever beams

来源：评论

学校读者我要写书评

暂无评论

AN INTRODUCTION TO THE USE OF FUZZY-SETS IN THE IMPLEMENTATION OF control algorithms

引用

JOURNAL OF THE INSTITUTION OF ELECTRONIC AND RADIO ENGINEERS 1985年第10期55卷 357-367页

作者： SUTTON, R TOWILL, DR UWIST DEPT MECH ENGN & ENGN PRODCARDIFF CF1 3XEWALES

The purpose of this paper is to present to the reader who is unfamiliar with fuzzy set theory the basic concepts in a straightforward manner. Thus a tutorial approach is adopted in the explanation of these concepts. After describing fuzzy sets, it is shown how fuzzy logic can be used to develop a fuzzy control algorithm by means of the fuzzy conditional statement. In order to unify the ideas that are presented, a detailed description of the development of a fuzzy controller is discussed. Computer simulation results are shown of the fuzzy controller with heading error and yaw rate as input and rudder demand as output activating the non-linear yaw dynamics of a ship during course-changing manoeuvres. For the simulation ship study, the model was derived from full-scale sea trials on a Royal Navy frigate.

关键词： fuzzy set theory nonlinear yaw dynamics fuzzy sets control algorithms fuzzy controller course-changing manoeuvres Combinatorial mathematics heading error ships Royal Navy control system synthesis rudder demand fuzzy conditional statement frigate Marine system control fuzzy logic ship control system analysis and synthesis methods yaw rate

来源：评论

学校读者我要写书评

暂无评论

An adaptive pressbrake control for strain-hardening materials

引用

Journal of Manufacturing Science and Engineering, Transactions of the ASME 1986年第2期108卷 127-132页

作者： Stelson, K.A. Intelligent Machines Laboratory Productivity Center Department of Mechanical Engineering and University of Minnesota Minneapolis MN 55455 United States

An improved adaptive pressbrake control algorithm is described. The problem is to control the punch reversal position of the press so that the final unloaded angle of the bend remains unchanged in the presence of material property and thickness variations of the sheets or plates being bent. Pressbrake control algorithms that use punch force-displacement data to identify thickness and material property variations have shown promise. However, since previous controllers have been based on an elastic-plastic material model, the parts have been overbent. In this paper, a controller based on an elastic, power-law strain-hardening model is proposed. Experiments have shown that the model eliminates the tendency to overbend the parts that is present in the elastic-plastic algorithm. © 1986 by ASME.

关键词： Materials properties Displacement control algorithms Work hardening Plates (structures) control equipment algorithms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：