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Explicit guidance of aeroassisted orbital transfer using matched asymptotic expansions

JOURNAL OF GUIDANCE control AND DYNAMICS 2002年第1期25卷 80-87页

作者： Kuo, ZS Liu, KC Natl Def Univ Chung Cheng Inst Technol Dept Mech Engn Tao Yuan 33509 Taiwan Natl Def Univ Chung Cheng Inst Technol Dept Aeronaut Engn Tao Yuan 33509 Taiwan

An explicit guidance of aeroassisted orbital transfer by using the method of matched asymptotic expansions is presented. The aeroassisted orbit transfer comprises three consecutive phases: a descending phase entering atmosphere with a negative flight path angle, a transatmospheric flight to deplete its excess energy, and an ascending flight targeting the desired apogee. Feedback control via lift modulation is used to guide the vehicle during the atmospheric fly-through, whereas a matched asymptotic solution for the exit trajectory is available to aim the apogee of the target orbit, thus determining the pull-up condition. The feedback control ensures the stability of a trajectory around the nominal trajectory by compensating for the nonlinear terms in the motion of the vehicle. When the method of matched asymptotic expansions is used, the control algorithms for the explicit guidance are derived and tested against the 1976 U.S. Standard Atmosphere. Simulation results indicate that the control algorithms can effectively control the trajectories in both the lower atmosphere and in the exit phase under the targeting dispersions of atmospheric variations.

关键词： Elliptical Transfer Orbit Apogee Altitude Feedback Linearization control algorithm Lift to Drag Ratio Aerodynamic Force Characteristic Velocity Earth Space Transportation System Numerical Integration

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Effectual Energy Consumption and User Comfort Optimization Based on Dynamic User Set Parameters in Electric Vehicles

IEEE TRANSACTIONS ON INTELLIGENT VEHICLES

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IEEE TRANSACTIONS ON INTELLIGENT VEHICLES 2024年第1期9卷 178-189页

作者： Fayaz, Muhammad Khan, Junaid Bilal, Muhammad Univ Cent Asia Sch Arts & Sci Dept Comp Sci Naryn 722900 Kyrgyzstan Chungnam Natl Univ Dept Environm & IT Engn Daejeon 34134 South Korea Univ Lancaster Sch Comp & Commun Lancaster LA1 4WA England

The reduction of energy usage and the enhancement of comfort indices within electric vehicles stand as key areas of focus for modern research. Numerous approaches have been devised to address these concerns, yet each of these models exhibit certain constraints;some effectively reduce energy usage yet do so at the cost of comfort, whereas others succeed in elevating comfort at the price of increased energy consumption. Our research introduces a comprehensive model that leverages optimization, machine learning, data smoothing, and control protocols to defeat these challenges. The purpose of the proposed model is two folds: firstly, to reduce energy use, and secondly, to enhance the comfort of the user. Our proposed model comprises three main modules: the smoothing, the optimization, and control modules. In the smoothing module, the alpha-beta filter, the simplest and most effective filter, has been used to remove noise and smooth the data. The optimization module is segmented into two additional modules: the FA-GA module and the support vector machine module. The purpose of the support vector machine in the optimization module is to make the system fully automatic and dynamic by setting user parameters in the objective function of the FA-GA module. Within the control module, Mamdani fuzzy logic is employed to deliver the appropriate energy to the respective actuators. The proposed technique is evaluated against several proven methods, with results suggesting that our approach achieves commendable results in comparison to similar algorithms.

关键词： Optimization Energy consumption Smoothing methods Genetic algorithms Machine learning algorithms Electric vehicles Petroleum Energy user comfort optimization electric vehicles control algorithm machine learning

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Determination of disturbances acting on small satellite mock-up on air bearing table

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ACTA ASTRONAUTICA 2018年 142卷 265-276页

作者： Ivanov, D. Koptev, M. Mashtakov, Y. Ovchinnikov, M. Proshunin, N. Tkachev, S. Fedoseev, A. Shachkov, M. RAS Keldysh Inst Appl Math Miusskaya Sq 4 Moscow Russia

In this paper the facility for the simulation of satellite motion based on planar air-bearing deweighting is considered. The air bearing provides almost frictionless horizontal motion of the small satellite mock-ups. Due to the presence of gravitational and air flow disturbances the motion is far from rectilinear and uniform. This paper is devoted to the determination of these disturbances.

关键词： Test-bench Disturbance determination control algorithm Motion determination

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Simulation model linked PV inverter implementation utilizing dSPACE DS1104 controller

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ENERGY AND BUILDINGS 2013年 57卷 65-73页

作者： Ghani, Z. A. Hannan, M. A. Mohamed, A. Univ Kebangsaan Malaysia Dept Elect Elect & Syst Engn Bangi 43600 Selangor Malaysia Univ Teknikal Malaysia Fac Elect & Comp Engn Melaka Malaysia

This paper presents the simulation model linked prototype development of a photovoltaic (PV) three-phase inverter utilizing the dSPACE DS1104 controller. The inverter model and control algorithm were developed and simulated in MATLAB/Simulink. The control algorithm of the simulation model is linked to the built inverter prototype by using the dSPACE DS1104 controller board. The control system employs the PI controller to generate the PWM signals for IGBTs switching, thus producing and regulating the 50 Hz sinusoidal ac output voltage. For the input sources, the inverter utilizes 25 units of real PV modules which generate a dc output voltage of 435 V. Simulation results show that the controller managed to regulate the rms output voltage of 240 V and 100% in magnitude of fundamental component. The test results show that the inverter rms output voltage and current are stabilized at 240 V and 4.5 A respectively. The total harmonic distortion (THD) of the voltage and current waveform are 2.5% and 3.5% respectively that proved the efficacy of the developed control algorithm. (c) 2012 Elsevier B.V. All rights reserved.

关键词： PV dSPACE Inverter SPWM control algorithm

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Development of modularized in-pipe inspection robotic system: MRINSPECT VII

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ROBOTICA 2022年第5期40卷 1361-1384页

作者： Jang, Heesik Kim, Ho Moon Lee, Min Sub Song, Yong Heon Lee, Yoongeon Ryew, Whee Ryeong Choi, Hyouk Ryeol Sungkyunkwan Univ Sch Mech Engn 300 ChunchunDong Suwon 440746 Kyougki Do South Korea H Robot 129 Gaetbeol Ro Incheon South Korea LG Elect 10 MagokJungang 10 Ro Seoul South Korea Korea Elect Power Corp KEPCO Res Inst 105 Munji Ro Daejeon South Korea KOGAS Res Inst Technol Support Ctr 376 Songdo Dong Incheon South Korea

This paper presents a modularized autonomous pipeline inspection robot called MRINSPECT VII+, which we recently developed. MRINSPECT VII+ is aimed at inspect in-service urban gas pipelines with a diameter of 200 mm. The robot consists of five basic modules: driving, sensing, joint, and battery modules. For nondestructive testing (NDT), an NDT module can be added to the system. The driving module uses a multiaxial differential gear mechanism to provide traction forces to the robot. The sensor module recognizes the pipeline element using position-sensitive detector (PSD) sensors and a CCD camera. The control module contains a computing unit and manages the robot's autonomous navigation. The battery module supplies power to the system. Each module is connected via backdrivable active joint modules, which provide flexibility while moving inside narrow pipelines. Additionally, the wireless communication module helps the system communicate with the ground station. We tested MRINSPECT VII+ in real pipeline environments and validated its feasibility successfully.

关键词： In-pipe robot industrial robot robot mechanism mobile robot control algorithm

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Novel voltage balancing algorithm for single-phase cascaded multilevel inverter for post-module failure operation in solar photovoltaic applications

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IET RENEWABLE POWER GENERATION 2019年第3期13卷 427-437页

作者： Rahman, Syed Meraj, Mohammad Iqbal, Atif Ben-Brahim, Lazhar Qatar Univ Dept Elect Engn Doha Qatar

Four cascaded quasi-impedance source inverter (qZSI) modules are required for achieving nine-level output voltage waveform. In case of one module failure, number of levels in output voltage are reduced to seven. This leads to decrease in the output voltage magnitude and increased THD (higher than conventional seven-level qZSI). This is due to the dominance of unwanted harmonic component introduced in the harmonic spectrum. To restore voltage magnitude and optimize THD performance, novel voltage balancing algorithm is proposed. To validate the control algorithm for off-grid and grid connected system, simulation results of the multilevel qZSI are discussed in two categories: (i) DC voltage source powered multilevel qZSI for RL load subjected to module failure and (ii) solar powered multilevel qZSI connected to utility grid subjected to module failure and variable solar irradiation. Pre-fault and post-fault performance of the system with the proposed control algorithm is discussed for both categories, which validates the effectiveness of the algorithm. Hardware results for proof-of-concept are discussed for DC voltage source fed cascaded qZSI connected to RL load during pre-fault and post-fault conditions. FPGA Virtex-5 is used for hardware implementation of the control algorithm. The results validate the improvement in output voltage both quantitatively and qualitatively.

关键词： photovoltaic power systems harmonic distortion switching convertors PWM invertors solar power stations power generation faults failure analysis power generation reliability voltage-source convertors power grids power generation control novel voltage balancing algorithm post-module failure operation nine-level output voltage waveform nine-level four module qZSI seven-level three modules voltage levels output voltage magnitude harmonic profile output voltage level total harmonic distortion seven-level qZSI output voltage unwanted harmonic component conventional cascaded H-bridge inverters pre-fault condition multilevel inverter operation post-fault condition control algorithm DC voltage source solar powered multilevel qZSI post-fault performance cascaded qZSI single-phase cascaded multilevel inverter solar photovoltaic applications single-phase cascaded quasiimpedance source inverter modules harmonic spectrum CHB inverters post-fault operation restoration buck mode boost modes voltage balancing algorithm module failure DC voltage source powered multilevel qZSI utility grid pre-fault performance RL load FPGA Virtex 5 digital platform H

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SURVEY OF TIME-OPTIMAL ATTITUDE MANEUVERS

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JOURNAL OF GUIDANCE control AND DYNAMICS 1994年第2期17卷 225-233页

作者： SCRIVENER, SL THOMPSON, RC Pennsylvania State University University Park Pennsylvania 16802

Studies related to time-optimal attitude maneuvers, conducted over the past thirty years, are reviewed. Specific topics covered include flexibility effects, equations of motion, control and model development, rigid-body solutions, flexible spacecraft, and specific configurations. The survey traces the development of time-optimal and near time-optimal control algorithms and includes many of the more recent advances in the field. (AIAA)

关键词： Transversality Condition Magnetic Attitude control Large Space Structures Aerospace Engineering Composite Materials Structural Dynamics Linear Quadratic Regulator Flexible Spacecrafts control algorithm Satellites

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Nonlinear projection filter based on Galerkin approximation

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JOURNAL OF GUIDANCE control AND DYNAMICS 1999年第2期22卷 258-266页

作者： Beard, R Kenney, J Gunther, J Lawton, J Stirling, W Brigham Young Univ Dept Elect & Comp Engn Provo UT 84602 USA

The conditional probability density function of the state of a stochastic dynamic system represents the complete solution to the nonlinear filtering problem because, with the conditional density in hand, all estimates of the state, optimal or otherwise, can be computed. It is well known that, for systems with continuous dynamics, the conditional density evolves, between measurements, according to Kolmogorov's forward equation, At a measurement, it is updated according to Bayes formula. Therefore, these two equations can be viewed as the dynamic equations of the conditional density and, hence, the exact nonlinear filter. In this paper, Galerkin's method is used to approximate the nonlinear filter by solving for the entire conditional density. Using a discrete cosine transform to approximate the projections required in Galerkin's method leads to a computationally realizable nonlinear filter, The implementation details are given and performance is assessed through simulations.

关键词： Galerkin Method Probability Density Functions Nonlinear Systems Computing Robust control Digital Signal Processors Industrial Applications control algorithm Hilbert Space

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DSP based proportional integral sliding mode controller for photo-voltaic system

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INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS 2015年第Oct.期71卷 123-130页

作者： Bhat, Subramanya Nagaraja, H. N. VTU Canara Engn Coll Dept E&C Mangalore Belgaum India Indus Univ Ahmadabad Gujarat India

The buck-boost converter is controlled using different algorithms like voltage mode control, current mode control, V-2 control, enhanced V-2 control, Sliding Mode control (SMC), and Proportional Integral (PI) control. In all these algorithms the steady state error is more. On combining PI control and sliding mode control the steady error can be minimized. In industry and commercial applications involving Photo-Voltaic (PV) systems, uses buck-boost converter. In this converter above control algorithms are implemented using hardware circuitry or microcontroller. In industry and commercial applications Digital Signal Processor (DSP) is used for automation purposes and the same DSP can be used to implement control algorithms so as to get maximum electrical energy from solar energy. The efficient utilization of resources such as DSP is achieved as we are using the same DSP for implementing control algorithm. In the proposed study, PI control method and sliding mode control methods are combined to obtain a Proportional Integral Sliding Mode control (PISMC) and it is used to control the buck-boost converter which is used to drive the electrical loads from solar energy. The buck-boost converter is designed, simulated and implemented. The algorithms PI, SMC and PISMC are simulated in using MATLAB simulink and then implemented in DSP TMS 320 2808. In the proposed study PISMC, a stable and efficient output voltage is obtained in which the steady state error and maximum overshoot are minimum. The PISMC is better in terms of transient and steady state performances as validated by our experiments. The proposed study will work in real-time since DSP is used for implementing the control algorithms and found to be better in terms of speed and regulation. The proposed DSP based PISMC can also be used to control other types of DC-DC converters. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Steady state error control algorithm DC loads Regulation

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COMPARISON OF LOW-EARTH-ORBIT SATELLITE ATTITUDE controlLERS SUBMITTED TO controlLABILITY CONSTRAINTS

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JOURNAL OF GUIDANCE control AND DYNAMICS 1994年第4期17卷 795-804页

作者： STEYN, WH Stellenbosch Univ. South Africa

A rule-based fuzzy controller is presented and compared with an adaptive MIMO LQR controller in a low-Earth-orbit small satellite attitude control system. The attitude is passively gravity gradient stabilized and actively three-axis magnetorquer controlled. This method insures an Earth-pointing satellite making use of a nondepletable and nonmechanical means of control. A realistic simulation environment, using a nonlinear satellite dynamic model with linear attitude estimators plus sensor measurement noise and external disturbance torques, was used to evaluate the different control techniques.

关键词： Low Earth Orbit Satellites Linear Quadratic Regulator Magnetorquer Earth Sensor Systems Satellite Attitude control control Surfaces Geomagnetic Field Magnetometers control algorithm

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