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Optimal guidance and decentralised state estimation applied to a formation flying demonstration mission in GTO

IET CONTROL THEORY AND APPLICATIONS 2007年第2期1卷 532-544页

作者： Dumitriu, D. Marques, S. Lima, P. U. Bastante, J. C. Araujo, J. Penin, L. F. Caramagno, A. Udrea, B. Univ Tecn Lisboa Inst Sistemas & Robot Inst Super Tecn P-1049001 Lisbon Portugal Romanian Acad Inst Solid Mech Bucharest Romania DEIMOS Space SL Madrid 28760 Spain DEIMOS Engn SA P-1998022 Lisbon Portugal European Space Agcy Estec NL-2200 AG Noordwijk Netherlands

An integrated approach to guidance, navigation and control (GNC) of formation flying spacecraft (sc) is introduced. The design process considers a three-sc mission in a reference geostationary transfer orbit (GTO). A detailed definition of the mission framework, in terms of GNC modes and corresponding science and technology requirements, is provided. This, together with an analysis of the dynamic environment of the mission, establishes inputs to the design of a low-thrust optimal relative configuration that minimises the fuel consumption and overall complexity. The obtained solution is assessed in detail by means of an analysis considering perturbations acting over a sc in Earth GTO. The GNC closed loop uses the results of the mission analysis and design process as specifications. An algebraic closed-loop algorithm is proposed for the guidance and control (GC) subsystem, minimising the propellant consumption and ensuring collision avoidance. Using Pontryagin's maximum principle, the GC algorithm provides the optimal trajectories from the current state until the target state, as well as the optimal control inputs to follow these trajectories. A full-order decentralised filter implements the navigation algorithm. It estimates the full state of the involved sc and is based on an extended Kalman filter (EKF) for local measurements, and on a covariance intersection (CI) algorithm (plus the EKF prediction part) for the fusion between local state estimates and state estimates communicated by other sc. Results of applying the GNC algorithms to a realistic simulation of the specified mission are presented. The main original contribution of the work presented here is the design of the formation flying mission and algorithms using a top-down approach. From a requirement to maximise the time which can be used for experimentation at the apogee, the orbits of the three sc, as well as the propellant optimal manoeuvres for formation (re)acquisition, have been determined. A novel ap

关键词： closed loop algorithm multivariable control systems closed loop systems state estimation formation flying demonstration mission navigation algorithm nonlinear filters formation flying spacecraft extended Kalman filter optimal control collision avoidance Earth geostationary transfer orbit navigation space vehicles decentralised state estimation maximum principle optimal guidance covariance intersection Kalman filters

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Autonomous airborne refueling of unmanned air vehicles using the global positioning system

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JOURNAL OF AIRCRAFT 2007年第5期44卷 1670-1682页

作者： Khanafseh, Samer M. Pervan, Boris IIT Mech Mat & Aerosp Engn Dept Chicago IL 60616 USA

Autonomous airborne refueling requires that the position of the receiving aircraft relative to the tanker be known very accurately and in real time. To meet this need, highly precise carrier-phase differential global positioning system solutions are being considered as the basis for navigation. However, the tanker introduces severe sky blockage into the autonomous airborne refueling mission, which reduces the number of visible global positioning system satellites and hence degrades the positioning accuracy. In this paper, we analyze the autonomous airborne refueling navigation problem in detail, define an optimal navigation architecture, and quantify navigation system availability. As part of this work, a high-fidelity dynamic sky-blockage model is developed and used to plan autonomous airborne refueling flight tests. The flight tests were conducted to obtain time-tagged global positioning system and attitude data that were processed offline to validate the blockage model.

关键词： Differential Global Positioning System Air Vehicle Satellite Constellations Flight Test Cards In Flight Refueling Constellations GPS Satellites Vertical Dilution of Precision Inertial navigation System navigation algorithm

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Course and heading changes in significant wind

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2007年第4期30卷 1168-1171页

作者： Rysdyk, Rolf Univ Washington Dept Aeronaut & Astronaut Autonomous Flight Syst Lab Seattle WA 98195 USA

USING straightforward differential geometry, this note presents a path formulation for maneuvering of a fixed wing aircraft in wind. The results accommodate analytical development and minimize heuristics of path-planning and decision-making algorithms. This note also makes the dynamic difference between course and heading rates explicit. This is significant for the coupling of guidance and navigation algorithms to the vehicle augmentation loops.

关键词： navigation algorithm Guidance Laws Aerodynamic Lift Fixed Wing Aircraft Yaw Airspeed Path Planning Standard Rate Turn Kalman Filter Closed Loop

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FPGA realization of mobile robot controller using fuzzy algorithm

FPGA realization of mobile robot controller using fuzzy algo...

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9th WSEAS International Conference on Automatic Control, Modeling and Simulation

作者： Islam, Shabiul Zaman, Mukter Azim, Anwarul Othman, Masuri Multimedia Univ Fac Engn Cyberjaya 63100 Selangor Malaysia Univ Kebangsaan Malaysia Dept Elect Elect & Syst Engn Bangi 43600 Malaysia

ISBN: (纸本)9789608457720

This paper describes a Fuzzy Logic Controller (FLC) algorithm for designing an autonomous mobile robot controller (MRC). The controller enables the robot to navigate in an unstructured environment and that avoid any encountered obstacles without human intervention. The autonomous mobile robot is found to be able to react to the environment appropriately during its navigation to avoid crashing with obstacles by turning to the proper angle while moving. The Fuzzy Logic algorithm has proven a commendable solution in dealing with certain control problems when the situation is ambiguous. One of the main difficulties faced by conventional control systems is the inability to operate in a condition with incomplete and imprecise information. As the complexity of a situation increases, a traditional mathematical model will be difficult if not impossible to implement. Fuzzy Logic is a tool for modeling uncertain systems by facilitating common sense reasoning in decision-making in the absence of complete and precise information. In this paper, the controller of an autonomous mobile robot is designed based on the theories of Fuzzy algorithm. The wheeled robot is able to navigate by itself in a completely unstructured environment. The codes of MRC has written for implementing the separate modules of the Fuzzifier, Fuzzy Rule Base, Inference mechanism and Defuzzifier as hardware blocks. A behavioral model of MRC algorithm is first developed in MATLAB platform with numerous data to evaluate its algorithm functionality. The development of MATLAB codes has converted into VHDL codes for hardware implementation. Comparison results between MATLAB and VHDL of MRC algorithm also have presented. Then the VHDL codes are synthesized to get MRC hardware blocks using synthesis tool, Quartus II from Altera environment. Finally the designed codes of MRC algorithm has been downloaded into FPGA board for verifying the functionality of algorithm for VLSI implementation.

关键词： fuzzy rules mobile robot controller navigation algorithm VHDL synthesis FPGA

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Physarum solver:: A biologically inspired method of road-network navigation

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PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS 2006年第1期363卷 115-119页

作者： Tero, A Kobayashi, R Nakagaki, T Hokkaido Univ Res Inst Elect Sci Sapporo Hokkaido 0600812 Japan Hiroshima Univ Dept Math & Life Sci Higashihiroshima 7398626 Japan Hokkaido Univ Creat Res Inst SOUSEI Sapporo Hokkaido 0010021 Japan

We have proposed a mathematical model for the adaptive dynamics of the transport network in an amoeba-like organism, the true slime mold Physarum polycephalum. The model is based on physiological observations of this species, but can also be used for path-finding in the complicated networks of mazes and road maps. In this paper, we describe the physiological basis and the formulation of the model, as well as the results of simulations of some complicated networks. The path-finding method used by Physarum is a good example of cellular computation. (c) 2006 Elsevier B.V. All rights reserved.

关键词： amoeboid movement navigation algorithm physarum polycephahum path-finding

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Design and synthesis of mobile robot controller using fuzzy

Design and synthesis of mobile robot controller using fuzzy

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IEEE International Conference on Semiconductor Electronics

作者： Islam, Md. Shabiul Azim, Md. Anwarul Jahan, Md. Saukat Othman, Masuri Multimedia Univ Fac Engn Cyberjaya 63100 Selangor Malaysia Univ Kebangsaan Malaysia Inst Microengn & Nanoelectron Bangi 43600 Malaysia

ISBN: (纸本)9780780397309

This paper describes a Fuzzy Logic Controller (FLC) algorithm for designing an autonomous mobile robot controller (MRC). The controller enables the robot to navigate in an unstructured environment and that avoid any encountered obstacles without human intervention. The autonomous mobile robot is found to be able to react to the environment appropriately during its navigation to avoid crashing with obstacles by turning to the proper angle while moving. The Fuzzy Logic algorithm has proven a commendable solution in dealing with certain control problems when the situation is ambiguous. One of the main difficulties faced by conventional control systems is the inability to operate in a condition with incomplete and imprecise information. As the complexity of a situation increases, a traditional mathematical model will be difficult if not impossible to implement. Fuzzy Logic is a tool for modeling uncertain systems by facilitating common sense reasoning in decision-making in the absence of complete and precise information. In this paper, the controller of an autonomous mobile robot is designed based on the theories of Fuzzy Logic. The wheeled robot is able to navigate by itself in a completely unstructured environment. The codes of MRC has written for implementing the separate modules of the Fuzzifier, Fuzzy Rule Base, Inference mechanism and Defuzzifier as hardware blocks. A behavioral model of MRC algorithm is first developed in MATLAB session with numerous data to evaluate its algorithm functionality. The development of MATLAB codes has converted into VHDL codes;for hardware implementation. Comparison results between MATLAB and VHDL of MRC algorithm also presented. Then the VHDL codes are synthesized using synthesis tool, known as Quartus II. Finally the MRC hardware blocks for VLSI design have been carried out.

关键词： fuzzy rules mobile robot controller navigation algorithm VHDL synthesis

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Development of fast map building algorithm for merchandise location guiding mobile robot

Development of fast map building algorithm for merchandise l...

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SICE-ICASE International Joint Conference

作者： Hong, Jin-Pyo Choi, You-Jun Park, Kyi-Hwan Gwanju Inst Sci & Technol Dept Mechatron Gwangju South Korea

ISBN: (纸本)9788995003848

In the public space, we need first of all the map building to guide the person into the desired position. For realizing this functionality, we propose the fast map building method combining the wall following algorithm and the segment estimation algorithm. First, the process of fast map building algorithm is introduced and secondly, the navigation algorithm for following the surface of a wall by IR sensors is proposed and local map building method by estimation of line segment is shown. We derive the correlation between the orthogonal wall distance and IR sensor data using trigonometric functions and the similarity ratio of a triangle. Finally, we verify that our proposed method is sufficiently valid as describing the experimental results using our developed mobile robot platform, GIMOR(GIST Mobile Robot)-I.

关键词： fast map building IR sensor laser range finder navigation algorithm local map building

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Underwater navigation in the presence of unknown currents based on range measurements from a single location

Underwater navigation in the presence of unknown currents ba...

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American Control Conference 2005 (ACC)

作者： Gadre, AS Stilwell, DJ Virginia Polytech Inst & State Univ Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA

ISBN: (纸本)0780390989

An underwater navigation algorithm is considered that enables an underwater vehicle to compute its trajectory in the presence of unknown currents by utilizing range measurements from a single known location. There exists a small set of trajectories for which the algorithm does not converge. By assessing local observability about potential vehicle trajectories, we characterize those trajectories that cannot be asymptotically estimated. The navigation algorithm is illustrated using computer simulation and a hardware experiment.

关键词： control system analysis computing navigation position control predictive control underwater vehicles computer simulation hardware experiment navigation algorithm range measurements trajectory computation underwater navigation underwater vehicle Ranging measurements Underwater navigation control system analysis computing underwater vehicles Trajectory calculation Position control Predictive control navigation trajectory

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INS algorithm using quaternon model for low cost IMU

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ROBOTICS AND AUTONOMOUS SYSTEMS 2004年第4期46卷 221-246页

作者： Kong, XY Univ Technol Sydney Fac Engn Sydney NSW 2007 Australia

This paper presents a generic inertial navigation system (INS) error propagation model that does not rely on small misalignment angles assumption. The modelling uses quaternions in the computer frame approach. Based on this model, an INS algorithm is developed for low cost inertial measurement unit (IMU) to solve the initial attitudes uncertainty using in-motion alignment. The distribution approximation filter (DAF) is used to implement the non-linear data fusion algorithm. (C) 2004 Elsevier B.V. All rights reserved.

关键词： quaternion inertial navigation system global positioning system navigation algorithm

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Bearings-only measurements for ins aiding: The three-dimensional case

Bearings-only measurements for ins aiding: The three-dimensi...

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American Control Conference

作者： Pachter, M Porter, A USAF Dept Elect & Comp Engn Wright Patterson AFB OH 45433 USA

ISBN: (纸本)0780383354

The theory behind Inertial navigation System (INS) aiding using passive, bearings-only measurements of an unknown ground object is developed. Passive, bearings-only measurements provide an effective means to aid an INS, but only the two-dimensional case was previously considered. This paper addresses the complexities of moving from two-dimensional to three-dimensional space. Stand-alone, bearings-only measurements of an unknown ground object are shown to yield estimates of the aircraft's aerodynamic angles, viz., the angle of attack and sideslip angle, which in turn are used to aid the INS. Using the synergy of INS state and passive, bearings-only measurements, a powerful navigation algorithm is developed.

关键词： inertial navigation inertial systems angular measurement aircraft navigation aerodynamics bearings only measurements INS aiding inertial navigation system three dimensional space stand alone measurements aircraft aerodynamic angles angle of attack sideslip angle navigation algorithm hybrid navigation systems Inertial navigation systems three-dimensional space inertial systems aircraft navigation Angle measurement ANGLE OF ATTACK INERTIAL navigation Aerodynamics bearing-only measurement

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