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Adaptive Image-Based Visual Servoing for an Underactuated Quadrotor System

JOURNAL OF GUIDANCE control AND DYNAMICS 2012年第4期35卷 1335-1353页

作者： Lee, Daewon Lim, Hyon Kim, H. Jin Kim, Youdan Seong, Kie Jeong Seoul Natl Univ Sch Mech & Aerosp Engn Seoul 151742 South Korea Korea Aerosp Res Inst Flight Control & Avion Team Taejon 305806 South Korea

This paper presents an adaptive image-based visual servoing (IBVS) integrated with adaptive sliding mode control for a vision-based operation of a quadrotor unmanned aerial vehicle (UAV). For a seamless integration with underactuated quadrotor dynamics, roll and pitch channels are decoupled from the other channels using virtual features. This allows a simple and accurate algorithm for estimating depth information and successful application of the proposed guidance and control algorithm. By employing an adaptive gain in the IBVS control method, the chance of image feature loss is reduced, and performance and stability of the vision-guided UAV control system are improved. The overall setup allows image features to be placed at the desired position in the image plane of a camera mounted on the quadrotor UAV. Stability of the IBVS system with the controller is proved using Lyapunov stability analysis. Performance of the overall approach is validated by numerical simulation, vision integrated hardware-in-the-loop simulation, and experiments. The results confirm that the target image is successfully placed at the desired position of the image plane and the quadrotor state variables are properly regulated, showing robustness in the presence of sensor noise, parametric uncertainty, and vibration from motors.

关键词： Visual Servoing Quadrotor Helicopter UAV Proportional Integral Derivative Inertial Sensor Single Input Single Output Numerical Simulation control algorithm Yaw control Helicopters

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Optimal location and gains of feedback controllers at discrete locations

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AIAA JOURNAL 1998年第11期36卷 2109-2116页

作者： Abdullah, MM Florida A&M Univ Dept Civil Engn Tallahassee FL 32310 USA

The dynamic responses of elastic Structures due to vibrations are very important and can produce conditions that can vary from uncomfortable to unsafe. For this reason, optimally designed and placed control devices are very important for the reduction of these vibrations. Many structures have limitations on where these control devices can be placed. However, many existing algorithms are not able to provide solutions to these nonlinear/discrete location problems. A new method is presented for optimal design of the placement and gains of actuators and sensors at discrete locations in output feedback control systems. The method extends the method of Xu et al. (Xu, K., Warnitchai, P., and Ingusa, T., "Optimum Locations and Gains of Sensors and Actuators for Feedback control," AIAA Paper 93-1660, 1993) by solving for the optimal placement at certain discrete locations. A new algorithm is introduced that will allow constrained optimization problems with solutions possible only at discrete locations to be modeled as unconstrained optimization problems. Numerical studies were performed on a two-dimensional structure. Convergence to optimal discrete solutions was efficient.

关键词： Sensors Lyapunov Equation Stiffness Matrices Eigenfunction Feedback control System Numerical Optimization Free Vibrations Structural Response Elastic Structure control algorithm

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FEEDFORWARD controlLER-DESIGN BY EIGENVALUE ASSIGNMENT

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JOURNAL OF GUIDANCE control AND DYNAMICS 1994年第3期17卷 466-472页

作者： BURDISSO, RA FULLER, CR Virginia Polytechnic Institute and State University Blacksburg Virginia 24061

Active feedforward control algorithms have proven to be successful in the attenuation of stationary disturbances such as single frequency, multiple frequencies, and random inputs. In feedforward control the mean square value of a measurable response quantity induced by the disturbance input is minimized by coherent ''secondary'' control inputs. The traditional design procedure is to choose the location/number of control forces and error sensors based on a physical understanding of the response of the uncontrolled and controlled systems. Thus, an analytical procedure for actuator and sensor design in feedforward controlled systems is nonexistent in contrast to feedback control where pole allocation, optimal control, etc., are extensively used. Recent analytical work has demonstrated that feedforward controlled systems have new eigenproperties. The controlled eigenvalues and eigenfunctions are only a function of the control input location and the error quantity to be minimized. Here, an eigenvalue assignment design methodology for feedforward controllers is presented, and it is based on designing an optimal error sensor such that the controlled system eigenvalues have predetermined values.

关键词： Distributed Parameter System Dirac Delta Function Adaptive Filter Sensors Feedback control System Optimal control control algorithm Actuators Frequency Response Functions Structural Vibration

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A study of a Kalman filter active vehicle suspension system using correlation of front and rear wheel road inputs

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2000年第D5期214卷 493-502页

作者： Yu, F Zhang, JW Crolla, DA Shanghai Jiao Tong Univ Sch Mech Engn Inst Automot Engn Shanghai 200030 Peoples R China Univ Leeds Dept Mech Engn Leeds LS2 9JT W Yorkshire England

Based on a half-vehicle model, an algorithm is proposed for a Kalman filter optimal active vehicle suspension system using the correlation between front and rear wheel road inputs. In this paper, two main issues were investigated, i.e. the estimation accuracy of the Kalman filter for state variables, and the potential improvements from wheelbase preview. Simulations showed good estimations from the state observer. However, if the wheelbase preview algorithm is incorporated, the estimation accuracy for the additional states significantly decreases as vehicle speed and the corresponding measurement noises increase. Significant benefits from wheelbase preview were further proved, and the available performance improvements of the rear wheel station could be up to 35 per cent. Because of the feasibility and effectiveness of the proposed algorithm, and no additional cost for measurements and sensing needs, wheelbase preview can be a promising algorithm for Kalman filter active suspension system designs.

关键词： vehicle active suspension control algorithm Kalman filter

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STEADY-STATE AND TRANSIENT CHARACTERISTICS OF A SINGLE-WAY STEP-DOWN PWM GTO VOLTAGE-SOURCE CONVERTER WITH SINUSOIDAL SUPPLY CURRENTS

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IEE PROCEEDINGS-B ELECTRIC POWER APPLICATIONS 1989年第4期136卷 168-174页

作者： ITOH, R Faculty of Engineering Fukuoka University Fukuoka Japan

The paper investigates the steady-state and transient characteristics of a single-way step-down voltage-source convertor, in which the introduction of pulsewidth modulation makes it possible to obtain the sinusoidal supply currents and the regulated output voltage. The tested system includes the simplified configuration employing the three gate turn-off thyristors and the PI controller for output voltage regulations, where the computational of control algorithm is executed by microcomputer. The experimental results and state-space simulations confirm the system's practical applications.

关键词： PI controller voltage control Power convertors and power supplies to apparatus sinusoidal supply currents steady-state characteristics two-term control gate turn-off thyristors transient characteristics thyristor applications Voltage control state-space simulations control of electric power systems pulsewidth modulation transients pulse width modulation step-down PWM GTO output voltage regulations voltage-source convertor microcomputer power convertors control algorithm

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EIGENSYSTEM ASSIGNMENT WITH OUTPUT-FEEDBACK

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JOURNAL OF GUIDANCE control AND DYNAMICS 1992年第2期15卷 531-536页

作者： MAGHAMI, PG JUANG, JN LIM, KB NASA Langley Research Center Hampton VA

In this paper, a new approach for the eigenvalue and eiigenvector assignment of linear, first-order, time-iinvariant systems is developed. Furthermore, the freedom provided by multi-inputs and multi-outpputs is charac... 详细信息

关键词： Full State Feedback Linear Quadratic Regulator Singular Value Decomposition Sideslip Angle Ailerons Dutch Roll Nonlinear Programming Electromechanical Actuator Flexible Structures control algorithm

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Stochastic and Dynamic Routing Problems for Multiple Uninhabited Aerial Vehicles

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JOURNAL OF GUIDANCE control AND DYNAMICS 2009年第4期32卷 1152-1166页

作者： Enright, John J. Savla, Ketan Frazzoli, Emilio Bullo, Francesco MIT Dept Aeronaut & Astronaut Informat & Decis Syst Lab Cambridge MA 02139 USA Univ Calif Santa Barbara Dept Mech Engn Santa Barbara CA 93106 USA Univ Calif Santa Barbara Ctr Control Dynam Syst & Computat Santa Barbara CA 93106 USA

Consider a routing problem for a team of vehicles in the plane: target points appear randomly over time in a bounded environment and must be visited by one of the vehicles. It is desired to minimize the expected system time for the targets, that is, the expected time elapsed between the appearance of a target point and the instant it is visited. In this paper, such a routing problem is considered fora team of uninhabited aerial vehicles, modeled as vehicles moving with constant forward speed along paths of bounded curvature. Three algorithms are presented, each designed for a distinct set of operating conditions. Each is proven to provide a system time within a constant factor of the optimal when operating under the appropriate conditions. It is shown that the optimal routing policy depends on problem parameters such as the workload per vehicle and the vehicle density in the environment. Finally, there is discussion of a phase transition between two of the policies as the problem parameters are varied. In particular, for the case in which target,;appear sporadically, a dimensionless parameter is identified which completely captures this phase transition and an estimate of the critical value of the-parameter is provided.

关键词： Uninhabited Aerial Vehicle Air Traffic control Robotics Weapon Target Assignment High Altitude Aircraft Numerical Optimization Aircraft Kinematics Multi Agent System control algorithm Motion Planning

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Comparison of Preshaping Profilers for Reducing Residual Vibrations After Rest-to-Rest Maneuvers

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JOURNAL OF GUIDANCE control AND DYNAMICS 2015年第5期38卷 874-885页

作者： Kamiya, Toshio Maeda, Ken Sakai, Shin-ichiro NEC Corp Ltd Div Space Syst Fuchu Tokyo 1838501 Japan Japan Aerosp Explorat Agcy Inst Space & Astronaut Sci Sagamihara Kanagawa 2298510 Japan

Generally, spacecraft with large flexible structures have multiple flexible modes with large effective masses and various mode shapes;therefore, the presence of uncertain high-order flexible modes should be considered in high-accuracy controller design. However, most researchers have proposed input preshaping algorithms that are valid only for a few flexible modes. Consequently, when these algorithms are applied to a flexible spacecraft having uncertain high-order flexible modes, residual vibrations might not be reduced sufficiently. This paper presents a smooth feedforward control algorithm for rest-to-rest maneuvers that significantly reduces residual vibrations at the endpoint of a maneuver. The new preshaping profiler is based on a filtering technique that combines a pair of sinc functions. The new profiler is compared to several conventional preshaping profilers. In addition, residual vibrations at the endpoint of maneuvers in the presence of unknown higher modes are found to be much smaller than those in other techniques. Only a hybrid-type profiler shows similar level of small residual vibrations comparable with the new profiler. The new profiler is suitable for rest-to-rest rotational maneuvers of a flexible spacecraft, especially when fine pointing accuracy is required at the endpoint of maneuvers;such accuracy is sometimes required for missions involving scientific observations.

关键词： Flexible Structures Feedforward control algorithm Flexible Spacecrafts Satellites Structural Vibration Shape Functions Time Optimal control Frequency Domain control Moment Gyros

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An Integrated Battery Charger With High Power Density and Efficiency for Electric Vehicles

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IEEE TRANSACTIONS ON POWER ELECTRONICS 2017年第6期32卷 4553-4565页

作者： Kim, Dong-Hee Kim, Min-Jung Lee, Byoung-Kuk Tongmyong Univ Dept Elect Engn Busan 48520 South Korea Sungkyunkwan Univ Sch Elect & Elect Engn Suwon 16419 South Korea

Power conversion systems for electric vehicles (EVs) have been researched to improve power density and efficiency at low cost. To satisfy these needs for EVs, this paper proposes a novel battery charging system that integrates a nonisolated on-board charger (OBC) and low-voltage dc-dc converters (LDCs) by sharing the semiconductor devices and mechanical elements. Thus, the volume of LDCs is reduced dramatically compared with a conventional nonintegrated charging system. The proposed integrated system is configured based on a driving condition that is derived from the analysis of vehicle operating modes. In order to improve system's performance, an asynchronous control algorithm is applied to control the OBC optimally. In the LDC system, two LLC resonant converters are composed by sharing a transformer and secondary-side components. To increase the efficiency of each LDC, which is operated in the wide input and output voltage range, a duty and frequency control algorithm is proposed. The theoretical analysis, operating strategy, and experimental results on a 6.6-kW OBC and 1.9-kW LDC are presented to evaluate the performance of the proposed system;the total volume of LDCs is 1.87 L, and peak efficiencies of OBC and LDC are 97.3% and 93.13%, respectively. Moreover, a comparative analysis is presented to evaluate the performance of the proposed system.

关键词： control algorithm electric vehicles (EVs) low-voltage dc-dc converter (LDC) on-board battery charger (OBC) system integration

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MVSI and AVSI-supported DSTATCOM for PQ Analysis

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IETE JOURNAL OF RESEARCH 2023年第6期69卷 3852-3858页

作者： Mangaraj, Mrutyunjaya Sabat, Jogeswara Lendi Inst Engn & Technol Vizianagaram India

This paper presents a dual voltage source inverter (DVSI)-based Distributed Static Compensator (DSTATCOM) to enhance the power quality in the power utility system (PUS). The proposed DSTATCOM consists of two numbers of two-level voltage source inverters (VSI) which controls the reactive power. One of them is regarded as the main voltage source inverter (MVSI) and the other is considered as auxiliary voltage source inverter (AVSI). The i cos phi control algorithm is employed to generate the reference source currents as well as switching pulses. The detailed control algorithm is formulated by mathematical analysis using MATLAB/Simulink, and compared with different case studies. Among all the theoretical findings, the DVSI offers better voltage regulation, voltage balancing, source current harmonic reduction and power factor correction under various loading scenarios. Apart from these, reliability, stress balancing of the both MVSI and AVSI, cost reduction due to a decrease in the filter size and better operation of PUS is obtained. To check the effectiveness, the performance of the DVSI-based DSTATCOM is carried out as per the benchmark value of the IEEE-519-2014 and IEC-61000-1 grid code.

关键词： AVSI DSTATCOM and PQ i cos phi control algorithm MVSI

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