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Passivity-Based Attitude control on the Special Orthogonal Group of Rigid-Body Rotations

JOURNAL OF GUIDANCE control AND DYNAMICS 2013年第6期36卷 1596-1605页

作者： Forbes, James Richard McGill Univ Montreal PQ H3A 0C3 Canada

Set-point regulation and tracking control of a rigid body is considered. The rigid body, which could be a spacecraft, underwater vehicle, or unmanned aerial vehicle, is equipped with various sensors, including those that provide unit-length vector measurements. At no point is the rotation matrix associated with the rigid-body's orientation parameterized. The control algorithms developed in this paper are posed directly on the special orthogonal group of rigid-body rotations SO(3). The set-point controller presented is composed of a proportional control term and an angular velocity control term. The proportional control term is a function of the vector measurements and a set of desired vector measurements that are used to compute the orientation error of the rigid body. Passive systems theory is used to motivate the use of a strictly positive real angular velocity controller. The set-point regulator is robust to modeling errors associated with the mass distribution of the body. Tracking control is also considered. To ensure robust tracking control, an adaptive scheme is developed in which the controller is composed of feedback and feedforward terms. The feedback term is composed of a proportional term and a strictly-positive-real-based angular velocity term, similar to the set-point regulator. The feedforward term is a function of an estimate of the spacecraft mass distribution. The synthesis of strictly positive real controllers to be used within the set-point and tracking controllers is discussed. Numerical simulation results that demonstrate successful set-point regulation and tracking control are presented.

关键词： Attitude control Linear Time Invariant System Sensors Unmanned Aerial Vehicle Numerical Simulation control algorithm Quaternions Poisson's Equation Earth Euler Equations

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Design and control of a three degree-of-freedom permanent magnet spherical actuator

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SENSORS AND ACTUATORS A-PHYSICAL 2012年 180卷 75-86页

作者： Chen, Weihai Zhang, Liang Yan, Liang Liu, Jingmeng Beihang Univ Sch Automat Sci & Elect Engn Beijing 100191 Peoples R China

This paper presents a permanent magnet (PM) spherical actuator embedded with a novel three-dimensional (3D) orientation measurement system. The study covers actuator design, torque modeling, and motion control. The spherical actuator consists of a stator with 24 coils and a rotor with 8 PM poles. A high accuracy and resolution, non-blinding 3D measurement mechanism is designed for the rotor orientation detection. The torque output is formulated from finite element (FE) computation and curve fitting method. Due to the nonlinear property of dynamic model, computed torque control law is utilized for the three degree-of-freedom (3-DOF) system motion control. The space geometry method is employed to study the redundancy feature of current inputs, which offers the opportunity for control optimization to improve the power efficiency and the fault tolerance capability of the spherical actuator. Simulations and experiments are then conducted on the developed prototype to validate the design concept, mathematic models and control strategy. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Spherical actuator Orientation measurement Torque modeling control algorithm

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Analysis of an interleaved control scheme employed in split source inverter based grid-tied photovoltaic systems

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IET RENEWABLE POWER GENERATION 2021年第6期15卷 1301-1314页

作者： Nannam, Hari Charan Banerjee, Atanu Guerrero, Josep M. Natl Inst Technol Meghalaya Shillong Meghalaya India Aalborg Univ Dept Energy Technol Aalborg Denmark

In conventional grid-tied renewable energy applications, the dc-dc converter is inevitable. An increased cost, size, and reduced efficiency are the demerits of incorporating a dc-dc converter. A recently introduced split source inverter (SSI) is capable to perform both dc-dc as well as dcac at a time. The main attractive controllable feature of SSI is its modulation index. By utilizing this parameter, an interleaved control structure is proposed for the SSI in grid-tied photovoltaic applications. The main objectives of the work are to track peak power and to maintain a stabilized voltage across the dc-link capacitor at a variable load and grid disturbances. The proposed peak power controller performs two important actions: (i) the peak power is traced at all irradiance and (ii) generates a duty cycle to enhance the dc-link capacitor voltage. The proposed scheme is essentially investigated with simulation. To validate experimentally, a 1 KW photovoltaic system is integrated into a grid-tied 10 kVA SSI prototype. A Xilinx based Spartan field-programmable gate array (FPGA) is used to provide a control algorithm for the SSI. Few case studies at different conditions are performed and investigated. Experimental and simulation results are presented to prove the robustness of the control strategy.

关键词： grid-tied renewable energy applications power control xilinx based spartan field-programmable gate array control of electric power systems FPGA Logic and switching circuits peak power controller Logic circuits control algorithm grid disturbances variable load invertors DC-DC power convertors power grids field programmable gate arrays dc-link capacitor voltage Solar power stations and photovoltaic power systems Power and energy control dc-dc converter Voltage control interleaved control structure photovoltaic power systems split source inverter based grid-tied photovoltaic systems renewable energy sources grid-tied 10 kVA SSI prototype photovoltaic system voltage control

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Experimental application of an active control loop on backward-facing step flow

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AIAA JOURNAL 2005年第6期43卷 1176-1186页

作者： Marrot, F Gajan, P Pauzin, S Simon, F Off Natl Etud & Rech Aerosp Aerodynam & Energet Models Dept F-31055 Toulouse France

Experimental results are presented on the active control of a backward-facing step flow revealing some features observed in combustion chambers. These experiments were performed under nonreactive conditions, and the effect of the pressure fluctuations induced by the unsteady heat release was simulated by an external acoustic excitation produced by two loudspeakers placed far downstream from the step., This excitation signal was delivered by a generator or by a hot-wire probe placed in the shear layer. The latter configuration reproduces some aspects of the actual coupling that have been observed with combustion instabilities. This preexcited flow was then controlled using six synthetic jets located on the vertical side of the step. The control loop uses an recursive least-mean-square autoadaptive algorithm applied to a signal from either a microphone or a hot-wire probe placed downstream of the step edge. The influence of the external acoustic excitationon the flow organization and the effect of the control loop are described. Without excitation, the control algorithm is not able to reduce the natural unsteady phenomena. However, it does damp the shear-layer pressure or velocity fluctuations intensified by an external excitation and bring the flow close to its natural feature. The efficiency of the control depends on the frequency of the external excitation, the signal used in the control loop, and the phase shift between the velocity and the pressure signals in the shear layer.

关键词： Active control Flow Separation Combustion Instability Acoustic Excitation Combustion Chambers control algorithm Strouhal Number Flow Conditions Flow Visualization Flow Characteristics

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Robust Attitude Coordination control for Spacecraft Formation Flying Under Actuator Failures

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JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第4期35卷 1247-1255页

作者： Zou, An-Min Kumar, Krishna Dev Ryerson Univ Dept Aerosp Engn Toronto ON M5B 2K3 Canada

This paper examines attitude coordination control for spacecraft formation flying. A class of distributed adaptive fault-tolerant attitude coordination control laws is proposed. The proposed control laws do not require online identification of failures. Using the Lyapunov approach and graph theory, it is shown that the control laws guarantee a group of spacecraft that simultaneously track a common time-varying reference attitude, even when the reference attitude is available only to a subset of the members of a group. Finally, numerical simulation is presented to show that the distributed controller is successful in achieving high-attitude tracking and synchronization performance, even in the presence of an unknown mass moment of inertia matrix, bounded external disturbances, actuator failures, and control saturation limits.

关键词： Spacecraft Formation Flying Actuators Attitude Tracking Numerical Simulation Attitude Stabilization Spacecraft Attitude Terminal Sliding Mode control algorithm Adaptive control Systems Onboard Computing

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A hybrid seismic response control to improve performance of a two-span bridge

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STRUCTURAL ENGINEERING AND MECHANICS 2017年第5期61卷 675-684页

作者： Heo, Gwanghee Kim, Chunggil Jeon, Seunggon Lee, Chinok Jeon, Joonryong Konyang Univ Dept Civil Engn 121 Daehak Ro Nonan 32992 Chungcheongnam South Korea Chungnam Natl Univ Dept Civil Engn 99 Daehak Ro Daejeon 34134 South Korea

In this paper, a hybrid seismic response control (HSRC) system was developed to control bridge behavior caused by the seismic load. It was aimed at optimum vibration control, composed of a rubber bearing of passive type and MR-damper of semi-active type. Its mathematical modeling was driven and applied to a bridge model so as to prove its validity. The bridge model was built for the experiment, a two-span bridge of 8.3 meters in length with the HSRC system put up on it. Then, inflicting the EI Centro seismic load on it, shaking table tests were carried out to confirm the system's validity. The experiments were conducted under the basic structure state (without an MR-damper applied) first, and then under the state with an MRdamper applied. It was also done under the basic structure state with a reinforced rubber bearing applied, then the passive on/off state of the HSRC system, and finally the semi-active state where the control algorithm was applied to the system. From the experiments, it was observed that pounding rather increased when the MR-damper alone was applied, and also that the application of the HSRC system effectively prevented it from occurring. That is, the experiments showed that the system successfully mitigated structural behavior by 70% against the basic structure state, and, further, when control algorithm is applied for the operation of the MR-damper, relative displacement was found to be effectively mitigated by 80%. As a result, the HSRC system was proven to be effective in mitigating responses of the two-span bridge under seismic load.

关键词： hybrid seismic response control system rubber bearing MR-damper shaking table test control algorithm

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Network Congestion control of Airport Surface Operations

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JOURNAL OF GUIDANCE control AND DYNAMICS 2014年第3期37卷 933-940页

作者： Khadilkar, Harshad Balakrishnan, Hamsa MIT Dept Aeronaut & Astronaut Cambridge MA 02139 USA

This paper presents a novel approach to managing the aircraft taxi-out process at airports, by posing the problem in a network congestion control framework. A network model of the airport surface with stochastic link travel times is first developed. The model parameters for Boston Logan International Airport are estimated using empirical data from a surface surveillance system. Using the entry times of aircraft into the network as the control variables, a control algorithm tha aims to reduce taxi-out times is proposed. This algorithm regulates network congestion while limiting the adverse effect on throughput performance. Performance characteristics of the proposed control algorithm are derived using simplified theoretical analysis, and are shown to agree with simulations of traffic on a network model of Boston Logan International Airport.

关键词： Airport Surface Operations Boston Logan International Airport Airport Surface Detection Equipment, Model X control algorithm Taxiway Optimal control Transmission control Protocol Federal Aviation Administration Unscented Kalman Filter Communication Channels

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control OF A SLOW-MOVING SPACE CRANE AS AN ADAPTIVE STRUCTURE

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AIAA JOURNAL 1991年第6期29卷 961-967页

作者： UTKU, S RAMESH, AV DAS, SK WADA, BK CHEN, GS DUKE UNIV DEPT COMP SCIDURHAMNC 27706 CALTECH JET PROP LABAPPL TECHNOL SECTPASADENACA 91109 CALTECH JET PROP LABTECH STAFFPASADENACA 91109

If we assume that the space crane is a statically determinate truss with length-adjustable bars and take as controls the length adjustments of these bars, the computation of the incremental controls corresponding to the motion of a payload along a trajectory is given in terms of the inverse-transpose of matrix B of the joint equilibrium equations Bs = p, where s lists the bar forces and p the nodal loads. An algorithm with O(n2) computational complexity and O(n) storage demand is used for obtaining the inverse of the nth-order sparse matrix B. The compensation of the controls for elastic deformations and support movements is shown. The crane is assumed to be moving sufficiently slowly so that no vibratory motion is created during its maneuver. To simplify the computations, a zero-acceleration field is assumed in the workspace of the space crane. It is shown that the computations may be done automatically and in real time by an attached processor once the characteristics of the crane's maneuver are keyed in.

关键词： Adaptive Structures Trusses Elastic Deformation Finite Element Modeling control algorithm Young's Modulus Earth Space Stations Robust control Computing

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The recursive generalized predictive feedback control: theory and experiments

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JOURNAL OF SOUND AND VIBRATION 2005年第1-2期279卷 171-199页

作者： Moon, SM Clark, RL Cole, DG Duke Univ Dept Mech Engn & Mat Sci Durham NC 27708 USA

The proposed adaptive control algorithm combines the recursive least-squares system identification algorithm and the generalized predictive control (GPC) design algorithm, referred to as recursive generalized predictive control (RGPC.) In the GPC design process, the prediction horizon and control horizon are the constants to be chosen. Two new parameters are defined to describe the effects of the prediction and control horizons and those parameters provide the effective ranges of the horizons. The RGPC algorithm adjusts the control penalty based on the stability of a closed-loop system model. A time-varying algorithm for the control penalty allows to design an aggressive controller. The multi-sampling rate algorithm is added between the system identification and the control design in order to design a higher order controller. The RGPC algorithm is applied to three different systems: a cantilevered beam, a sound enclosure. and an optical jitter suppression tesibed. (C) 2003 Published by Elsevier Ltd.

关键词： MULTIVARIABLE ADAPTIVE-control CONTINUOUS-TIME SYSTEMS SELF-TUNING control control algorithm AIRBORNE LASER MIMO SYSTEMS SUPPRESSION MATRIX PHASE

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Transient stability enhancement by series braking resistor control using local measurements

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INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS 2019年 112卷 272-281页

作者： Robak, Sylwester Gryszpanowicz, Konrad Piekarz, Michal Polewaczyk, Mateusz Warsaw Univ Technol Fac Elect Engn Warsaw Poland

Series braking resistors (SeBR) offer an effective way to enhance transient stability for severe near-to-generator faults cleared with a delay. The SeBR is switched on for a short time, already during the fault. The SeBR should switch on as quickly as possible after identifying the risk of losing transient stability. Then, the SeBR is switched off, and it is the decision-making algorithm that chooses the switch-off time. This paper presents an algorithm to choose the moment the SeBR switches off. The algorithm identifies the direction of a rotor motion based on changes in the square of the current and real power of the synchronous machine. The proposed algorithm is characterized by its simplicity, and is easy to implement because it uses local measurements. To develop the control algorithm, the effect of the SeBR on power angle characteristics for a fault state and post-fault states were determined. In addition, the effect of the SeBR on transient stability is explained using the equal area method. The conducted simulation tests have confirmed that the proposed SeBR control algorithm leads to longer critical clearing times, and thus it contributes to enhanced transient stability.

关键词： Power system stability Emergency control schemes Series braking resistor control algorithm Stability enhancement

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