Dissertations / Theses on the topic 'Guidance and control'

To see the other types of publications on this topic, follow the link: Guidance and control.

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Guidance and control.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Çelik, Ugurcan. "Robust Booster Landing Guidance/Control." Thesis, KTH, Optimeringslära och systemteori, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279684.

Full text
Abstract:
The space industry and the technological developments regarding space exploration hasn’t been this popular since the first moon landing. The privatization of space exploration and the vertical landing rockets made rocket science mainstream again. While being able to reuse rockets is efficient both in terms of profitability and popularity, these developments are still in their early stages. Vertical landing has challenges that, if neglected, can cause disastrous consequences. The existing studies on the matter usually don’t account for aerodynamics forces and corresponding controls, which results in higher fuel consumption thus lessening the economical benefits of vertical landing. Similar problems have been tackled in studies not regarding booster landings but regarding planetary landings. And while multiple solutions have been proposed for these problems regarding planetary landings, the fact that the reinforcement learning concepts work well and provide robustness made them a valid candidate for applying to booster landings. In this study, we focus on developing a vertical booster descent guidance and control law that’s robust by applying reinforcement learning concept. Since reinforcement learning method that is chosen requires solving Optimal Control Problems (OCP), we also designed and developed an OCP solver software. The robustness of resulting hybrid guidance and control policy will be examined against various different uncertainties including but not limited to wind, delay and aerodynamic uncertainty.
Rymdindustrin och den tekniska utvecklingen av rymdutforskningen har inte varit så populär sedan den första månlandningen. Privatiseringen av utforskningen av rymden och de vertikala landningsraketerna medförde att raketvetenskapen återkom som en viktig huvudfråga igen. Även om det är effektivt att återanvända raketer i form av lönsamhet och popularitet, är denna utveckling fortfarande i sina tidiga stadier. Vertikal landning har utmaningar som, om de försummas, kan orsaka katastrofala konsekvenser. De befintliga studierna i frågan redovisar vanligtvis inte aerodynamikkrafter och motsvarande regulatorer, vilket resulterar i högre bränsleförbrukning som minskar de ekonomiska fördelarna med vertikal landning. Liknande problem har hanterats i studier som inte avsåg boosterlandningar utan om planetariska landningar. Även om flera lösningar har föreslagits för dessa problem beträffande planetariska landningar, det faktum att förstärkningsinlärningskonceptet fungerar bra och ger robusthet gjorde dem till en giltig kandidat för att ansöka om boosterlandningar. I den här studien fokuserar vi på att utveckla en lagstiftning för styrning av vertikala booster-nedstigningar som är robust genom att tillämpa koncepten inom förstärkningsinlärning. Ef- tersom förstärkt inlärningsmetod som väljs kräver lösning av optimala kontrollproblem (OCP), designade och utvecklade vi också en OCP-lösningsmjukvara. Robustheten för resulterande hybridstyrning och kontrollpolicy kommer att undersökas mot olika osäkerheter inklusive, men inte begränsat till vind, fördröjning och aerodynamisk osäkerhet.
APA, Harvard, Vancouver, ISO, and other styles
2

Kørte, Steffen Østensjø. "Guidance & Control Strategies for UUVs." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16228.

Full text
Abstract:
Focus on safety and effectiveness in the oil and gas industry has increased the need for advanced control system for underwater vehicles. For remotely operated vehicles (ROVs) effectiveness when conducting deep sea operation is extremely critical both concerning safety and cost. For AUVs conducting survey missions, energy and collision avoidance are critical factors. A control system for ROV Minerva is being developed through the AUR-Lab at the Institute of Marine Technology at NTNU. Several guidance features have been investigated, with respect to different mission the ROV should be able to do. A guidance system has been developed, where basic functions such as a DP system with station keeping and trajectory tracking was the focus of the project thesis of the author. More advanced functionality with respect to path following has been developed, where focus have been set on different strategies to apply when the ROV is following a path. Simulations based on different strategies for following a lawnmower pattern have been simulated and evaluated with respect to time, energy and control objective. Full scale experiments with the ROV Minerva show that especially the forward speed versus arc radius is an important issue. The results show that the ROV is able to follow a path made out of straight lines and circular arcs, and particularly lawnmower patterns. For an underwater vehicle to be able to operate autonomously, stationary and dynamic obstacles have to be taken into account. A collision avoidance system based on local collision avoidance algorithms has been implemented, where focus has been on reactivity with respect to unmapped obstacles. The collision avoidance system has been through initial full scale tests with ROV Minerva, and the result are promising.
APA, Harvard, Vancouver, ISO, and other styles
3

Ilg, Mark Dean Chang Bor-Chin. "Guidance, navigation, and control for munitions /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2831.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Rubí, Perelló Bertomeu. "Guidance, navigation and control of multirotors." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/673068.

Full text
Abstract:
This thesis presents contributions to the Guidance, Navigation and Control (GNC) systems for multirotor vehicles by applying and developing diverse control techniques and machine learning theory with innovative results. The aim of the thesis is to obtain a GNC system able to make the vehicle follow predefined paths while avoiding obstacles in the vehicle's route. The system must be adaptable to different paths, situations and missions, reducing the tuning effort and parametrisation of the proposed approaches. The multirotor platform, formed by the Asctec Hummingbird quadrotor vehicle, is studied and described in detail. A complete mathematical model is obtained and a freely available and open simulation platform is built. Furthermore, an autopilot controller is designed and implemented in the real platform. The control part is focused on the path following problem. That is, following a predefined path in space without any time constraint. Diverse control-oriented and geometrical algorithms are studied, implemented and compared. Then, the geometrical algorithms are improved by obtaining adaptive approaches that do not need any parameter tuning. The adaptive geometrical approaches are developed by means of Neural Networks. To end up, a deep reinforcement learning approach is developed to solve the path following problem. This approach implements the Deep Deterministic Policy Gradient algorithm. The resulting approach is trained in a realistic multirotor simulator and tested in real experiments with success. The proposed approach is able to accurately follow a path while adapting the vehicle's velocity depending on the path's shape. In the navigation part, an obstacle detection system based on the use of a LIDAR sensor is implemented. A model of the sensor is derived and included in the simulator. Moreover, an approach for treating the sensor data to eliminate the possible ground detections is developed. The guidance part is focused on the reactive path planning problem. That is, a path planning algorithm that is able to re-plan the trajectory online if an unexpected event, such as detecting an obstacle in the vehicle's route, occurs. A deep reinforcement learning approach for the reactive obstacle avoidance problem is developed. This approach implements the Deep Deterministic Policy Gradient algorithm. The developed deep reinforcement learning agent is trained and tested in the realistic simulation platform. This agent is combined with the path following agent and the rest of the elements developed in the thesis obtaining a GNC system that is able to follow different types of paths while avoiding obstacle in the vehicle's route.
Aquesta tesi doctoral presenta diverses contribucions relaciones amb els sistemes de Guiat, Navegació i Control (GNC) per a vehicles multirrotor, aplicant i desenvolupant diverses tècniques de control i de machine learning amb resultats innovadors. L'objectiu principal de la tesi és obtenir un sistema de GNC capaç de dirigir el vehicle perquè segueixi una trajectòria predefinida mentre evita els obstacles que puguin aparèixer en el recorregut del vehicle. El sistema ha de ser adaptable a diferents trajectòries, situacions i missions, reduint l'esforç realitzat en l'ajust i la parametrització dels mètodes proposats. La plataforma experimental, formada pel cuadricòpter Asctec Hummingbird, s'estudia i es descriu en detall. S'obté un model matemàtic complet de la plataforma i es desenvolupa una eina de simulació, la qual és de codi lliure. A més, es dissenya un controlador autopilot i s'implementa en la plataforma real. La part de control està enfocada al problema de path following. En aquest problema, el vehicle ha de seguir una trajectòria predefinida en l'espai sense cap tipus de restricció temporal. S'estudien, s'implementen i es comparen diversos algoritmes de control i geomètrics de path following. Després, es milloren els algoritmes geomètrics usant xarxes neuronals per convertirlos en algoritmes adaptatius. Per finalitzar, es desenvolupa un mètode de path following basat en tècniques d'aprenentatge per reforç profund (deep Reinforcement learning). Aquest mètode implementa l'algoritme Deep Deterministic Policy Gradient. L'agent intel. ligent resultant és entrenat en un simulador realista de multirotors i validat en la plataforma experimental real amb èxit. Els resultats mostren que l'agent és capaç de seguir de forma precisa la trajectòria de referència adaptant la velocitat del vehicle segons la curvatura del recorregut. A la part de navegació, s'implementa un sistema de detecció d'obstacles basat en l'ús d'un sensor LIDAR. Es deriva un model del sensor i aquest s'inclou en el simulador. A més, es desenvolupa un mètode per tractar les mesures del sensor per eliminar les possibles deteccions del terra. Pel que fa a la part de guiatge, aquesta està focalitzada en el problema de reactive path planning. És a dir, un algoritme de planificació de trajectòria que és capaç de re-planejar el recorregut del vehicle a l'instant si algun esdeveniment inesperat ocorre, com ho és la detecció d'un obstacle en el recorregut del vehicle. Es desenvolupa un mètode basat en aprenentatge per reforç profund per l'evasió d'obstacles. Aquest mètode implementa l'algoritme Deep Deterministic Policy Gradient. L'agent d'aprenentatge per reforç s'entrena i valida en un simulador de multirotors realista. Aquest agent es combina amb l'agent de path following i la resta d'elements desenvolupats en la tesi per obtenir un sistema GNC capaç de seguir diferents tipus de trajectòries, evadint els obstacles que estiguin en el recorregut del vehicle.
Esta tesis doctoral presenta varias contribuciones relacionas con los sistemas de Guiado, Navegación y Control (GNC) para vehículos multirotor, aplicando y desarrollando diversas técnicas de control y de machine learning con resultados innovadores. El objetivo principal de la tesis es obtener un sistema de GNC capaz de dirigir el vehículo para que siga una trayectoria predefinida mientras evita los obstáculos que puedan aparecer en el recorrido del vehículo. El sistema debe ser adaptable a diferentes trayectorias, situaciones y misiones, reduciendo el esfuerzo realizado en el ajuste y la parametrización de los métodos propuestos. La plataforma experimental, formada por el cuadricoptero Asctec Hummingbird, se estudia y describe en detalle. Se obtiene un modelo matemático completo de la plataforma y se desarrolla una herramienta de simulación, la cual es de código libre. Además, se diseña un controlador autopilot, el cual es implementado en la plataforma real. La parte de control está enfocada en el problema de path following. En este problema, el vehículo debe seguir una trayectoria predefinida en el espacio tridimensional sin ninguna restricción temporal Se estudian, implementan y comparan varios algoritmos de control y geométricos de path following. Luego, se mejoran los algoritmos geométricos usando redes neuronales para convertirlos en algoritmos adaptativos. Para finalizar, se desarrolla un método de path following basado en técnicas de aprendizaje por refuerzo profundo (deep reinforcement learning). Este método implementa el algoritmo Deep Deterministic Policy Gradient. El agente inteligente resultante es entrenado en un simulador realista de multirotores y validado en la plataforma experimental real con éxito. Los resultados muestran que el agente es capaz de seguir de forma precisa la trayectoria de referencia adaptando la velocidad del vehículo según la curvatura del recorrido. En la parte de navegación se implementa un sistema de detección de obstáculos basado en el uso de un sensor LIDAR. Se deriva un modelo del sensor y este se incluye en el simulador. Además, se desarrolla un método para tratar las medidas del sensor para eliminar las posibles detecciones del suelo. En cuanto a la parte de guiado, está focalizada en el problema de reactive path planning. Es decir, un algoritmo de planificación de trayectoria que es capaz de re-planear el recorrido del vehículo al instante si ocurre algún evento inesperado, como lo es la detección de un obstáculo en el recorrido del vehículo. Se desarrolla un método basado en aprendizaje por refuerzo profundo para la evasión de obstáculos. Este implementa el algoritmo Deep Deterministic Policy Gradient. El agente de aprendizaje por refuerzo se entrena y valida en un simulador de multirotors realista. Este agente se combina con el agente de path following y el resto de elementos desarrollados en la tesis para obtener un sistema GNC capaz de seguir diferentes tipos de trayectorias evadiendo los obstáculos que estén en el recorrido del vehículo.
APA, Harvard, Vancouver, ISO, and other styles
5

Alsaif, Saif A. "Echoic Flow for Guidance and Control." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543864969419357.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Wright, David Andrew. "Guidance and control of sounding rockets." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/5077.

Full text
Abstract:
Includes abstract.
Includes bibliographical references.
This dissertation presents the design, fabrication and testing of a sounding rocket flight computer for the South African Astronomical Observatory (SAAO). Sounding rockets carry instruments with which to take measurements in the Earth’s atmosphere in sub-orbital flight. The South African Astronomical Observatory (SAAO) requires a flight computer for their sounding rockets. This flight computer is to replace the current commercial flight computer currently in use improving on its functionality and expandability.
APA, Harvard, Vancouver, ISO, and other styles
7

Hallberg, Eric N. "On integrated plant, control and guidance design." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA341957.

Full text
Abstract:
Dissertation (Ph.D. in Aeronautics and Astronautics) Naval Postgraduate School, September 1997.
"September 1997." Dissertation supervisor(s): Isaac I. Kaminer. Includes bibliographical references (p. 187-190). Also available online.
APA, Harvard, Vancouver, ISO, and other styles
8

Dellicker, Scott Henry. "Low cost parachute guidance, navigation, and control." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA369203.

Full text
Abstract:
Thesis (M.S. in Aeronautical Engineering) Naval Postgraduate School, September 1999.
"September 1999". Thesis advisor(s): Richard M. Howard, Isaac I. Kaminer. Includes bibliographical references (p. 91-92). Also available online.
APA, Harvard, Vancouver, ISO, and other styles
9

Simakis, Dimitrios A. "Vehicle guidance and control along circular trajectories." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/24101.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

McConnell, George. "Digital bank-to-turn control and guidance." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303013.

Full text
APA, Harvard, Vancouver, ISO, and other styles
11

Zhou, Jingyang. "Optimal guidance and control in space technology." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/1503.

Full text
Abstract:
In this thesis, we deal with several optimal guidance and control problems of the spacecrafts arising from the study of lunar exploration. The research is composed of three parts: 1. Optimal guidance for the lunar module soft landing, 2. Spacecraft attitude control system design basing on double gimbal control moment gyroscopes (DGCMGs), and 3. Synchronization motion control for a class of nonlinear system.To achieve a precise pinpoint lunar module soft landing, we first derive a three dimensional dynamics to describe the motion of the module for the powered descent part by introducing three coordinate frames with consideration of the moon rotation. Then, we move on to construct an optimal guidance law to achieve the lunar module soft landing which is treated as a continuously powered descent process with a constraint on the angle of the module between its longitudinal axis and the moon surface. When the module reaches the landing target, the terminal attitude of the module should be within an allowable small deviation from being vertical with reference to lunar surface. The fuel consumption and the terminal time should also be minimized. The optimal descent trajectory of the lunar module is calculated by using the control parameterization technique in conjunction with a time scaling transform. By these two methods, the optimal control problem is approximated by a sequence of optimal parameter selection problems which can be solved by existing gradient-based optimization methods. MISER 3.3, a general purpose optimal control software package, was developed based on these methods. We make use of this optimal control software package to solve our problem. The optimal trajectory tracking problem, where a desired trajectory is to be tracked with the least fuel consumption in the minimum time, is also considered and solved.With the consideration of some unpredicted situations, such as initial point perturbations, we move on to construct a nonlinear optimal feedback control law for the powered deceleration phase of the lunar module soft landing. The motion of the lunar module is described in the three dimensional coordinate system. Based on the nonlinear dynamics of the module, we obtain the form of an optimal closed loop control law, where a feedback gain matrix is involved. It is then shown that this feedback gain matrix satisfies a Riccati-like matrix differential equation. The optimal control problem is first solved as an open loop optimal control problem by using the time scaling transform and the control parameterization method. By virtue of the relationship between the optimal open loop control and the optimal closed loop control along the optimal trajectory, we present a practical method to calculate an approximate optimal feedback gain matrix, without having to solve an optimal control problem involving the complex Riccati-like matrix differential equation coupled with the original system dynamics.To realize the spacecraft large angle attitude maneuvers, we derive an exact general mathematical description of spacecraft attitude motion driven by DGCMGs system. Then, a nonlinear control law is designed based on the second method of Lyapunov and the stability of the attitude control system is established during the design process. A singularity robustness plus null motion steering law is designed to realize the control law. Principle of DGCMGs’ singularity is proved, and the singularity analysis of the orthogonally mounted three DGCMGs system and that of the parallel mounted four DGCMGs system are presented.Finally, we consider a new class of nonlinear optimal tracking and synchronizing control problems subject to control constraints, where the motions of two distinct objects are required to achieve synchronization at the minimum time while achieving the optimal tracking of a reference target. We first provide a rigorous mathematical formulation for this class of optimal control problems. A new result ensuring the synchronization of the two distinct objects is obtained. On this basis, a computational method is developed for constructing an optimal switching control law under which the motions of the two distinct objects will achieve synchronization at the minimum time while achieving the optimal tracking of a reference target. This computational method is developed based on novel applications of the control parameterization method and a time scaling transform. A practical problem arising from the study of the angular velocity tracking and synchronization of two spacecrafts during their formation flight is formulated and solved by the method proposed.
APA, Harvard, Vancouver, ISO, and other styles
12

PEREZ, MONTENEGRO CARLOS NORBERTO. "NAVIGATION, GUIDANCE AND CONTROL FOR PLANETARY LANDING." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2557338.

Full text
Abstract:
This dissertation aims to develop algorithms of guidance and control for propulsive terminal phase planetary landing, including a piloting strategy. The algorithms developed here are based on the Embedded Model Control (EMC) principles. Currently, the planetary entry descent and landing are important issues, landing on Mars and Moon has been scientifically rewarding; successful landed robotic systems on the surface of Mars have been achieved. Projects as Mars Science Laboratory MSL inter alia have achieved a successful landing. These new approaches are focused in delivering large amounts of mass with a low uncertainty and in performing the entry, descent and landing sequence for human exploration. The dissertation is divided in two parts, the first part is focused on Pinpoint landing algorithms, piloting definition and its integration with guidance; some simulations runs are provided. The second part of this research describes the Borea project. It shows the modelling of quadrotor dynamics and kinematics. Its propulsive system is studied and an alternative methodology for the propeller modelling is presented. The embedded model control for quadrotor vehicles is developed. Test of GNC algorithms for planetary landing were studied and simulated. The dissertation is divided in two parts, the first part is focused on Pinpoint landing algorithms, piloting definition and its integration with guidance, some simulations runs are provided. The second part of this research describes the Borea project. shows modelling of quadrotor dynamics and kinematics. Its propulsive system is studied and an alternative methodology for the propeller modelling is presented. The embedded model control for quadrotor vehicles is developed. Test of GNC algorithms for planetary landing were studied and simulated.
APA, Harvard, Vancouver, ISO, and other styles
13

Best, Robert Andrew. "Integrated tracking and guidance." Thesis, University of Birmingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322491.

Full text
APA, Harvard, Vancouver, ISO, and other styles
14

Rogers, Andrew Charles. "Optimization-Based Guidance for Satellite Relative Motion." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/79455.

Full text
Abstract:
Spacecraft relative motion modeling and control promises to enable or augment a wide range of missions for scientific research, military applications, and space situational awareness. This dissertation focuses on the development of novel, optimization-based, control design for some representative relative-motion-enabled missions. Spacecraft relative motion refers to two (or more) satellites in nearly identical orbits. We examine control design for relative configurations on the scale of meters (for the purposes of proximity operations) as well as on the scale of tens of kilometers (representative of science gathering missions). Realistic control design for satellites is limited by accurate modeling of the relative orbital perturbations as well as the highly constrained nature of most space systems. We present solutions to several types of optimal orbital maneuvers using a variety of different, realistic assumptions based on the maneuver objectives. Initially, we assume a perfectly circular orbit with a perfectly spherical Earth and analytically solve the under-actuated, minimum-energy, optimal transfer using techniques from optimal control and linear operator theory. The resulting open-loop control law is guaranteed to be a global optimum. Then, recognizing that very few, if any, orbits are truly circular, the optimal transfer problem is generalized to the elliptical linear and nonlinear systems which describe the relative motion. Solution of the minimum energy transfer for both the linear and nonlinear systems reveals that the resulting trajectories are nearly identical, implying that the nonlinearity has little effect on the relative motion. A continuous-time, nonlinear, sliding mode controller which tracks the linear trajectory in the presence of a higher fidelity orbit model shows that the closed-loop system is both asymptotically stable and robust to disturbances and un-modeled dynamics. Next, a novel method of computing discrete-time, multi-revolution, finite-thrust, fuel-optimal, relative orbit transfers near an elliptical, perturbed orbit is presented. The optimal control problem is based on the classical, continuous-time, fuel-optimization problem from calculus of variations, and we present the discrete-time analogue of this problem using a transcription-based method. The resulting linear program guarantees a global optimum in terms of fuel consumption, and we validate the results using classical impulsive orbit transfer theory. The new method is shown to converge to classical impulsive orbit transfer theory in the limit that the duration of the zero-order hold discretization approaches zero and the time horizon extends to infinity. Then the fuel/time optimal control problem is solved using a hybrid approach which uses a linear program to solve the fuel optimization, and a genetic algorithm to find the minimizing time-of-flight. The method developed in this work allows mission planners to determine the feasibility for realistic spacecraft and motion models. Proximity operations for robotic inspection have the potential to aid manned and unmanned systems in space situational awareness and contingency planning in the event of emergency. A potential limiting factor is the large number of constraints imposed on the inspector vehicle due to collision avoidance constraints and limited power and computational resources. We examine this problem and present a solution to the coupled orbit and attitude control problem using model predictive control. This control technique allows state and control constraints to be encoded as a mathematical program which is solved on-line. We present a new thruster constraint which models the minimum-impulse bit as a semi-continuous variable, resulting in a mixed-integer program. The new model, while computationally more expensive, is shown to be more fuel-efficient than a sub-optimal approximation. The result is a fuel efficient, trajectory tracking, model predictive controller with a linear-quadratic attitude regulator which tracks along a pre-computed ``safe'' trajectory in the presence of un-modeled dynamics on a higher fidelity orbital and attitude model.
Ph. D.
APA, Harvard, Vancouver, ISO, and other styles
15

Febbo, Marco. "Advanced 4DT flight guidance and control software system." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11239/.

Full text
Abstract:
The work presented in this thesis has been part of a Cranfield University research project. This thesis aims to design a flight control law for large cargo aircraft by using predictive control, which can assure flight motion along the flight path exactly and on time. In particular this work involves the modelling of a Boeing C-17 Globemaster III 6DOF model (used as study case), by using DATCOM and Matlab Simulink software. Then a predictive control algorithm has been developed. The majority of the work is done in a Matlab/Simulink environment. Finally the predictive control algorithm has been applied on the aircraft model and its performances, in tracking given trajectory optimized through a 4DT Research Software, have been evaluated.
APA, Harvard, Vancouver, ISO, and other styles
16

Swee, John C. S. "Missile terminal guidance and control against evasive targets." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA378653.

Full text
Abstract:
Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, March 2000.
Thesis advisor(s): Hutchins, Robert G. "March 2000." Includes bibliographical references (p. 83). Also available online.
APA, Harvard, Vancouver, ISO, and other styles
17

Karasu, Caglar. "Small-size Unmanned Model Helicopter Guidance And Control." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605595/index.pdf.

Full text
Abstract:
The deployment of unmanned aerial vehicles (UAV) in military applications increased the research about them and the importance of them. The unmanned helicopters are the most agile and maneuverable vehicles among the unmanned aerial vehicles (UAV). The ability of hovering and low speed cruise makes them even more attractive. Such abilities supply more areas to deploy the usage of the unmanned helicopters like search &
rescue, mapping, surveillance. Autonomy is the key property for these vehicles. In order to provide autonomy to an unmanned vehicle, the guidance and the autopilot units are designed in the first step. Waypoints are used to track the desired trajectories. The line of sight guidance is used to reach an active waypoint. In order to realize the guidance commands controllers are designed by using LQR. In addition, position and heading controllers are designed by root-locus method. The trimming and linearization are implemented in order to extract linear models used for controller design. Keywords: Helicopter, control, guidance
APA, Harvard, Vancouver, ISO, and other styles
18

Ozkan, Bulent. "Dynamic Modeling, Guidance, And Control Of Homing Missiles." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606533/index.pdf.

Full text
Abstract:
DYNAMIC MODELING, GUIDANCE, AND CONTROL OF HOMING MISSILES Ö
ZKAN, Bü
lent Ph. D., Department of Mechanical Engineering Supervisor: Prof. Dr. M. Kemal Ö
ZGÖ
REN Co-Supervisor: Dr. Gö
kmen MAHMUTYAZICIOgLU September 2005, 236 pages In this study, the dynamic modeling, guidance, and control of a missile with two relatively rotating parts are dealt with. The two parts of the missile are connected to each other by means of a roller bearing. In the first part of the study, the governing differential equations of motion of the mentioned missile are derived. Then, regarding the relative rotation between the bodies, the aerodynamic model of the missile is constructed by means of the Missile Datcom software available in TÜ
BiTAK-SAGE. After obtaining the required aerodynamic stability derivatives using the generated aerodynamic data, the necessary transfer functions are determined based on the equations of motion of the missile. Next, the guidance laws that are considered in this study are formulated. Here, the Linear Homing Guidance and the Parabolic Homing Guidance laws are introduced as alternatives to the Proportional Navigation Guidance law. On this occasion, the spatial derivation of the Proportional Navigation Guidance law is also done. Afterwards, the roll, pitch and yaw autopilots are designed using the determined transfer functions. As the roll autopilot is constructed to regulate the roll angle of the front body of the missile which is the controlled part, the pitch and yaw autopilots are designed to realize the command signals generated by the guidance laws. The guidance commands are in the form of either the lateral acceleration components or the flight path angles of the missile. Then, the target kinematics is modeled for a typical surface target. As a complementary part of the work, the design of a target state estimator is made as a first order fading memory filter. Finally, the entire guidance and control system is built by integrating all the models mentioned above. Using the entire system model, the computer simulations are carried out using the Matlab-Simulink software and the proposed guidance laws are compared with the Proportional Navigation Guidance law. The comparison is repeated for a selected single-body missile as well. Consequently, the simulation results are discussed and the study is evaluated.
APA, Harvard, Vancouver, ISO, and other styles
19

Le, Voyer Damien. "Guidance and Control of a Naval Cruise Missile." Thesis, KTH, Reglerteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105890.

Full text
Abstract:
Today the armed forces of many countries need to strike accurately potential enemies, wherever they might be, from a safe place. Since naval units can be deployed almost everywhere in the open sea, the idea of a naval cruise missile emerged in the 70’s. These missiles are designed to be launched from various naval vehicles such as frigates or submarines and strike deeply in the enemy territory. A program called Missile de Croisière Naval (MdCN Naval Cruise Missile) was therefore launched in 2006 by the DGA, the French procurement agency. MBDA is the industrial company appointed by the DGA to design and build the missile. Control aspects on a cruise missile are of primary interest since they impact the reliability, performance and availability of the weapon. In the aeronautics and weapon industry, gain scheduled controllers are used in most cases. However, many non-linear techniques have  been developed in the literature and might improve the behaviour of the missile. The main objective of the present thesis is to apply non-linear techniques on the control and guidance loops of the MdCN too see whether of not they can improve such a system. Based on this report it should be easy for the engineers of the DGA to compare the controllers of the thesis and the classical gain scheduled controllers used in the industry. To achieve this task some basic knowledge of flight dynamics are recalled and a model of the MdCN is computed and divided into the control loop and the guidance loop. Then a non-linear controller for the launch phase using a Lyapunov based technique called back-stepping is designed and tested through a statistic analysis. During the cruise phase different anti-windup strategies are applied on the propulsion control loop of the missile and compared. Finally a software interface with a navigation-dedicated tool is coded and implemented in Simulink to analyse the complete Guidance-Navigation-Control loop and to see how navigation errors impact the control algorithms. The main contributions of this thesis are the controllers designed for the launch phase and the propulsion loop that will be compared with the controller that MBDA is going to deliver next year to see whether or not the non-linear techniques used in the thesis should be used on the missile. Furthermore, all the tools and procedure set up to interface the control and guidance laws with the navigation models and filters will give the possibility to the DGA to have a deeper understanding of the algorithms used by MBDA and to make sure that navigation and estimation issues are properly taken in account when designing the control and guidance laws.
APA, Harvard, Vancouver, ISO, and other styles
20

Preciado, Michael Patrick. "The compatibility of guidance control and reformed theology." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=235593.

Full text
Abstract:
In this thesis, I ask whether reformed theology is compatible with guidance control. I conclude that they are compatible. The main areas of compatibility are fourfold. First, both deny the sourcehood condition. Second, both deny the alternative possibilities condition. Third, both are types of reasons-responsive theories. Finally, both have a similar subjectivist condition. This conclusion implies that the resources of guidance control can be constructively used, developed and applied by reformed theologians and philosophers. Guidance control can be applied to the debates on free will and moral responsibility as well as to ethics and other related fields.
APA, Harvard, Vancouver, ISO, and other styles
21

Funaya, Koichi. "Manipulator control with obstacle avoidance using local guidance." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/34041.

Full text
APA, Harvard, Vancouver, ISO, and other styles
22

Gurunathan, Mohan 1975. "Guidance, navigation and control of a robotic fish." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50052.

Full text
Abstract:
Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.
Includes bibliographical references (p. 70).
by Mohan Grurnathan.
S.B.and M.Eng.
APA, Harvard, Vancouver, ISO, and other styles
23

Naeem, Wasif. "Guidance and control of an autonomous underwater vehicle." Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/2822.

Full text
Abstract:
A cooperative project between the Universities of Plymouth and Cranfield was aimed at designing and developing an autonomous underwater vehicle named Hammerhead. The work presented herein is to formulate an advance guidance and control system and to implement it in the Hammerhead. This involves the description of Hammerhead hardware from a control system perspective. In addition to the control system, an intelligent navigation scheme and a state of the art vision system is also developed. However, the development of these submodules is out of the scope of this thesis. To model an underwater vehicle, the traditional way is to acquire painstaking mathematical models based on laws of physics and then simplify and linearise the models to some operating point. One of the principal novelties of this research is the use of system identification techniques on actual vehicle data obtained from full scale in water experiments. Two new guidance mechanisms have also been formulated for cruising type vehicles. The first is a modification of the proportional navigation guidance for missiles whilst the other is a hybrid law which is a combination of several guidance strategies employed during different phases of the flight. In addition to the modelling process and guidance systems, a number of robust control methodologies have been conceived for Hammerhead. A discrete time linear quadratic Gaussian with loop transfer recovery based autopilot is formulated and integrated with the conventional and more advance guidance laws proposed. A model predictive controller (MPC) has also been devised which is constructed using artificial intelligence techniques such as genetic algorithms (CA) and fuzzy logic. A CA is employed as an online optimization routine whilst fuzzy logic has been exploited as an objective function in an MPC framework. The CA-MPC autopilot has been implemented in Hammerhead in real time and results demonstrate excellent robustness despite the presence of disturbances and ever present modelling uncertainty. To the author's knowledge, this is the first successful application of a CA in real time optimization for controller tuning in the marine sector and thus the thesis makes an extremely novel and useful contribution to control system design in general. The controllers are also integrated with the proposed guidance laws and is also considered to be an invaluable contribution to knowledge. Moreover, the autopilots are used in conjunction with a vision based altitude information sensor and simulation results demonstrate the efficacy of the controllers to cope with uncertain altitude demands.
APA, Harvard, Vancouver, ISO, and other styles
24

Green, David N. (David Norman) Carleton University Dissertation Engineering Mechanical. "Guidance and control of an autonomous planetary rover." Ottawa, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
25

Martinson, Nicholas S. "Obstacle avoidance guidance and control for autonomous satellites." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0041033.

Full text
APA, Harvard, Vancouver, ISO, and other styles
26

Morgan, Robert W. "A New Paradigm in Optimal Missile Guidance." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194121.

Full text
Abstract:
This dissertation investigates advanced concepts in terminal missile guidance. The terminal phase of missile guidance usually lasts less than ten seconds and calls for very accurate maneuvering to ensure intercept. Technological advancements have produced increasingly sophisticated threats that greatly reduce the effectiveness of traditional approaches to missile guidance. Because of this, terminal missile guidance is, and will remain, an important and active area of research. The complexity of the problem and the desire for an optimal solution has resulted in researchers focusing on simplistic, usually linear, models. The fruit of these endeavors has resulted in some of the world's most advanced weapons systems. Even so, the resulting guidance schemes cannot possibly counter the evolving threats that will push the system outside the linear envelope for which they were designed. The research done in this dissertation greatly extends previous research in the area of optimal missile guidance. Herein it is shown that optimal missile guidance is fundamentally a pairing of an optimal guidance strategy and an optimal control strategy. The optimal guidance strategy is determined from a missile's information constraints, which are themselves largely determined from the missile's sensors. The optimal control strategy is determined by the missile's control constraints, and works to achieve a specified guidance strategy. This dichotomy of missile guidance is demonstrated by showing that missiles having different control constraints utilize the same guidance strategy so long as the information constraints are the same. This concept has hitherto been unrecognized because of the difficulty in developing an optimal control for the nonlinear set of equations that result from control constraints. Having overcome this difficulty by indirect means, evidence of the guidance strategy paradigm emerged. The guidance strategy paradigm is used to develop two advanced guidance laws. The new guidance laws are compared qualitatively and quantitatively with existing guidance laws.
APA, Harvard, Vancouver, ISO, and other styles
27

Haugen, Joakim. "Guidance Algorithms for Planar Path-based Motion Control Scenarios." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10036.

Full text
Abstract:

The problem of performing accurate path maneuvering tasks in planar space is investigated in thesis. The purpose is to utilize limited knowledge about the vehicle's maneuverability constraints to output feasible reference signals. Acceleration limitations of the vehicle have been used in an algorithm that determines forward speeds in such way that a predefined path can be followed at high speeds. The algorithm ensures that the speed is reduced before acute turns. Furthermore, an existing steering law has been modified to dynamically take the limitations of the vehicle into consideration when determining the desired course. This modified steering law exhibits desirable convergence characteristics toward the desired path. A complete guidance system, which combines the path convergence algorithm with the path speed algorithm, has been proposed. This system is able to rapidly converge to the desired path and follow this path, even for paths where the curvature is large. The modified steering law has been combined with a path-tracking speed controller. The path-tracking speed controller makes sure the vehicle can track a target on a predefined path. The resulting path-tracking system is able to follow a leader vehicle's path by creating accurate paths online from periodically sampled positions. A method for creating feasible U-turns in a lawn-mower pattern has been proposed. For a given vehicle speed, the resulting path obeys angular speed and angular acceleration constraints. Finally, the proposed algorithms are tested in simulations to illustrate their behavior and usefulness.

APA, Harvard, Vancouver, ISO, and other styles
28

Ahiska, Kenan. "Control And Guidance Of An Unmanned Sea Surface Vehicle." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614705/index.pdf.

Full text
Abstract:
In this thesis, control and guidance algorithms for unmanned sea surface vehicles are studied. To design control algorithms of different complexity, first a mathematical model for an unmanned sea surface vehicle is derived. The dynamical and kinematical equations for a sea surface vehicle are obtained, and they are adapted to real life conditions with necessary additions and simplifications. The forces and torques effecting on the vehicle are investigated in detail. Control algorithms for under-actuated six degrees-of-freedom model are designed. PID and LQR controllers are implemented to attain desired surge speed and yaw position. The autopilots are designed and their performances are compared. Based on the autopilots, a guidance algorithm is implemented to achieve desired motions of the vehicle. An obstacle avoidance algorithm is proposed for safe motion among the obstacles. A next-point generation algorithm is designed to direct the vehicle to the most appropriate next way-point if the one ahead is missed. The effects of disturbances on the motion of the vehicle are studied thoroughly on simulation results. PID controller for an unmanned sea surface vehicle is implemented on ArduPilot Mega v1.4 cart controlling a Traxxas Spartan model boat. The performance of the controller is validated. Simulations and experimental results are provided.
APA, Harvard, Vancouver, ISO, and other styles
29

Papasotiriou, Evangelos G. "Three dimensional pursuit guidance and control of submersible vehicles." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26808.

Full text
Abstract:
Approved for public release; distribution is unlimited
A pure pursuit guidance law is combined with a heading autopilot to provide accurate path keeping of submersible vehicles. The scheme is implemented and analyzed in both the horizontal and vertical planes. A complete stability analysis is performed in order to evaluate regions of stable vehicle operations. Numerical integrations support the analytic predictions. Two distinct stability boundaries are established. In the first, the vehicle loss of stability is accompanied by the generation of oscillatory motions around the commanded path. In the second, loss of stability occurs with linearly increasing path deviation. The horizontal and vertical plane schemes are combined with a propulsion control law in order to achieve path tracking of a general commanded route composed of several straight line segments in three dimensional space.
APA, Harvard, Vancouver, ISO, and other styles
30

Cloutier, Michael John. "Guidance and control system for an Autonomous Underwater Vehicle." Thesis, Monterey, California. Naval Postgraduate School, 1990. http://hdl.handle.net/10945/30635.

Full text
Abstract:
Approved for public release, distribution is unlimited
The Naval Postgraduate School (NPS) is currently involved in a long-term project to investigate and develop real-time control software, artificial intelligence, computer architecture and control systems theory as they pertain to U.S. Navy autonomous vehicle programs. In support of this goal, the NPS is currently designing and fabricating a testbed autonomous underwater vehicle. This work describes the design, development, and testing of a Guidance Subsystem for this testbed vehicle which uses portions of cubic spirals as the desired path to follow between waypoints. In addition, data translation firmware and real-time software for the control surfaces and main motors is designed, implemented and tested. The process of selecting and implementing an appropriate computer architecture in support of these goals is also discussed and detailed, along with the choice of associated computer hardware and real-time operating system software.
APA, Harvard, Vancouver, ISO, and other styles
31

Pauck, Simon James. "Movement control and guidance of an automated underwater vehicle." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4244.

Full text
Abstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: This thesis presents the design process of the movement control and guidance systems for an automated underwater vehicle (AUV) constructed by the Institute of Maritime Technology in Simon’s Town. The full non-linear mathematical model and simulation environment for the AUV were previously developed in [1]. The design process in this thesis covers an analysis of existing test data and the performance of the current systems in place on the AUV, derivation and analysis of the linear model for the AUV, design of upgraded control and guidance systems, analysis of the new designs including simulation results, practical implementation of the new designs and the results thereof. Over the course of this project a number of flaws were identified in the original control designs and other aspects of the AUV. Most notably, the capability of the AUV is limited owing to its construction, and the current control and guidance methods result in poor movement characteristics. The new control designs are executed through multiple SISO feedback loops, with the most complicated controllers consisting of proportional and integral control. A completely new guidance method was designed which grants theAUVthe ability to track both straight line and circular path segments with no steady state error. These designs were tested in simulation, with results showing good tracking performance, even in the presence of output disturbances. The new designs were implemented on the physical AUV, but testing was limited, with poor results being obtained. The poor test results were caused primarily by the construction of the AUV.
AFRIKAANSE OPSOMMING: Hierdie tesis stel die ontwerpsproses voor vir die bewegingsbeheer- en navigasiestelsels vir ’n outonome duikboot wat gebou is deur die Instituut vir Maritieme Tegnologie in Simonstad. Die volle nie-lineˆere wiskundige model en simulasieomgewing vir die duikboot is voorheen ontwikkel in [1]. Die ontwerpsproses in hierdie tesis behels ’n analise van bestaande toetsdata en van die werksverrigting van die stelsels wat tans op die duikboot ge¨ınstalleer is, die afleiding en analise van ’n lineˆere model vir die duikboot, die ontwerp van verbeterde beheer- en navigasiestelsels, die analise van die nuwe ontwerpe, wat simulasieresultate insluit, die praktiese implementering van die nuwe ontwerpe, en die resultate daarvan. Deur die loop van die projek is ’n aantal tekortkominge ge¨ıdentifiseer in die oorspronklike beheerstelselontwerpe en ander aspekte van die duikboot. Die mees beduidende tekortkominge is dat die vermo¨e van die duikboot beperk word deur die konstruksie daarvan, en dat die huidige beheer- en navigasietegnieke swak bewegingseienskappe lewer. Die nuwe beheerstelselontwerpe is uitgevoer deur ’n aantal enkelintree, enkeluittree terugvoerlusse, waar die mees komplekse beheerders bestaan uit proporsionele en integraalbeheer. ’n Heeltemal nuwe navigasiemetode is ontwerp, wat die duikboot in staat stel om beide reguit lyne en sirkulˆere padsegmente te volg sonder ’n stasionˆere volgfout. Hierdie ontwerpe is getoets in simulasie, waar die resultate goeie volging getoon het, selfs in die teenwoordigheid van uittreeversteurings. Die nuwe ontwerpe is ge¨ımplementeer op die fisiese duikboot, maar beperkte toetse is gedoen, en het swak resultate gelewer. Die swak toetsresultate was hoofsaaklik as gevolg van die konstruksie van die duikboot.
APA, Harvard, Vancouver, ISO, and other styles
32

Cowling, Adam Lloyd. "Pitch-Control Predictor-Corrector and Neural Network Ascent Guidance." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32330.

Full text
Abstract:
A pitch-control predictor-corrector ascent guidance algorithm has been developed and evaluated for a rocket-based upper stage of a two-stage-to-orbit launch vehicle. Detailed descriptions of the predictor-corrector algorithm and a neural network loop modification are given. The mission requirement is insertion into a stable 50 x 100 nmi orbit at 375,000 ft altitude, coasting toward apogee at a positive inertial flight path angle. Three degree-of-freedom trajectory analysis is performed using the Program to Optimize Simulated Trajectories (POST2). Results of Monte Carlo simulations including uncertainties in atmosphere, thrust, aerodynamics and initial state are presented and compared to trajectories optimized for maximum injected weight.
Master of Science
APA, Harvard, Vancouver, ISO, and other styles
33

Tanakitkorn, Kantapon. "Guidance, control and path planning for autonomous underwater vehicles." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/412635/.

Full text
Abstract:
Over-actuated, hover-capable autonomous underwater vehicles (AUVs) are hybrid vehicles designed to serve a wide range of operations, from detailed survey tasks in a hover style to long-range exploration tasks in a flight style. Due to the over-actuated design and the different operating styles, it is challenging to operate these types of AUVs. This research developed a navigation system for over-actuated, hover-capable AUVs, with a primary focus on interconnections between guidance, control and path planning systems. A detailed 6-degrees of freedom mathematical model was developed to represent dynamics of these hybrid AUVs. The model was validated with horizontal plane manoeuvring trials carried out on the over-actuated, hover-capable Delphin2 AUV. The results showed that the model can satisfactorily predict the AUV's response over a range of operating conditions. Using this dynamics model, the guidance and control systems were designed to effectively and efficiently operate over a range of forward speeds with a seamless transition between hover-style and flight-style operation. A path planning system was tested, seeking for the collision-free path between two locations that requires the least energy for an AUV to navigate along. The proposed navigation system has been verified on the Delphin2 AUV through experiments. The comprehensive results have shown that the system can maintain excellent performance regardless of a range of forward speeds. By applying the proposed navigation system, it is also possible to launch a long-endurance AUV from a shore. The vehicle would be able to automatically navigate along an energy efficient path to perform, for instance, a seabed survey mission at a remote part of the ocean, then come back to the recovery point. This concept eliminates a ship from the AUV launching process, hence, making the operation more cost-effective.
APA, Harvard, Vancouver, ISO, and other styles
34

Bouzid, Yasser. "Guidance and control system for autonomous aerial vehicles navigation." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLE014.

Full text
Abstract:
Cette thèse traite du guidage et du pilotage de véhicules aériens qui peuvent assurer des missions dans des lieux particulièrement hostiles, dangereux ou inaccessibles avec des véhicules conventionnels. Nous sommes tout d'abord motivés par le scénario de couverture, qui est généralement un processus long pouvant utiliser un grand nombre de personnes et d'équipements. Or, la nature de la couverture nécessite un véhicule aérien avec des capacités de vol stationnaire. Pour cela, nous nous intéressons alors aux multirotors, qui sont considérés comme une bonne étude de cas pour concevoir, analyser et mettre en œuvre des stratégies de contrôle de vol.En réalité, de nombreux défis sont encore ouverts pour ce qui concerne le scénario de couverture comme la faisabilité, l’optimalité en visitant tous les points d’intérêts. De plus, un système de contrôle robuste est indispensable pour contrer des effets néfastes tel le vent. Par ailleurs, la conception d'un algorithme de contrôle répondant à certaines exigences (structure simple, précision, énergie minimale consommée) constitue un défi supplémentaire. Ensuite, notre travail introduit un modèle mathématique générique pour les multi-rotors en considérant l’effet du vent.Dans la première partie du manuscrit, nous proposons des planificateurs en utilisant comme base l'algorithme RRT* (optimal Rapidly-exploring Random Tree). En fait, dans les grands espaces, un grand nombre de nœuds est généré augmentant alors le temps de calcul et la mémoire consommée. Pour y remédier, une procédure de suppression est impliquée pendant le processus « ReWire » pour les réduire. De plus, un planificateur multidirectionnel qui renvoie un ensemble de chemins optimaux à partir d'un point de départ et d'un ensemble de points objectifs est proposé. Notre travail introduit également une stratégie CPP (Coverage path-planning) optimale dans un espace contraint. Celle-ci consiste à procéder par un algorithme en deux phases. Dans la première, un planificateur multidirectionnel est utilisé pour définir les chemins les plus courts de chaque point à ses voisins. Dans la seconde phase, au moyen des coûts entre les points, le chemin global le plus court est obtenu en résolvant un problème de voyageur en utilisant des algorithmes génétiques. Puis, compte tenu de l'énergie embarquée limitée, un problème de routage est adapté et est résolu par la méthode de savings. Dans une seconde partie, nous nous sommes penchés sur la conception d'un système de pilotage efficace permettant au véhicule de suivre une trajectoire paramétrée dans le temps. D’une part nous proposons une extension de la commande par modèle interne au non-linéaire (NLIMC). Notre technique repose sur l’utilisation du principe de base IMC pour synthétiser un contrôleur non linéaire qui fait intervenir la propriété de platitude. D’autre part, nous proposons une autre forme de contrôleur dont la structure apparente est un PID mais dans lequel est incorporée la technique des modes glissants que l'on appellera aussi PID non linéaire bien qu’il diffère de l’existant. Cette combinaison a l’avantage de conduire à un bon niveau de robustesse fourni par les modes glissants et en même temps à un bon comportement spécifié par la structure PID. En outre, en guise de complément, nous proposons deux contrôleurs redondants basés sur deux principes distincts afin de booster et d’améliorer les capacités de tout contrôleur. Le premier est basé sur l’approche MFC (Model-Free Control) tandis que le second est basé sur les modes glissants dynamiques DSMC (Dynamic Sliding Mode Controller). Enfin, pour montrer les performances de ces contrôleurs, nous avons effectué une série de tests avec plusieurs illustrations et scénarios, nous avons dressé un tableau de comparaison avec les approches conventionnelles. Les résultats issus des simulations numériques et ceux des tests expérimentaux réalisés sur un drone quadrotor se sont avérés cohérents et semblent bien prometteurs
This thesis deals with the guidance and control of aerial vehicles, which can also ensure missions in hostile, dangerous environments, or inaccessible workspaces with conventional vehicles. First, we are motivated by the coverage scenario, which is in general a long process, requiring a large number of individuals and specific equipment. However, the nature of sensing coverage requires an aerial vehicle with hovering capabilities. For this purpose, we are interested in multirotors that are considered as a good case study to design, analyze and implement flight control strategies.As matter of fact, many challenges are still open with respect to the coverage scenario such as for instance the feasibility and the optimality when passing through the Points of Interest. In addition, a robust control system is essential to mitigate the adverse effects such as the wind. Moreover, designing a control algorithm, which meet some requirements (simplicity, accuracy, consumed energy, etc.) constitutes a complementary challenge. Then, our work introduces a generic mathematical model for multirotors flying under the effect of wind.In a first part, we propose planners using as a basis the optimal Rapidly-exploring Random Tree (RRT*) algorithm. In fact, in large workspaces, a large number of nodes is generated and then increasing the computation time and the consumed memory. To counter these latter, a removal procedure is involved during the rewiring process. In addition, a multidirectional planner that returns a set of optimal paths from a starting point and a set of objective points is proposed. Our work also introduces an optimal Coverage path-planning (CPP) strategy in a constrained workspace. This one proceeds through a two-phases algorithm. In the first one, a Connected Multi-directional planner is used to define the shortest paths from each point to its neighbors. In the second phase, by means of the pair-wise costs between points, the overall shortest path is obtained by solving a Traveling Salesman Problem using Genetic Algorithms. Then, taking into account the limited on-board energy, a Capacitated-Vehicle Routing Problem is adapted and solved by the savings approach.In a second part, we study the design of an effective control system allowing the vehicle to track a trajectory parameterized in time. On the one hand, we propose an extension to nonlinear systems of the Internal Model Control (NLIMC). Our technique is based on the use of the basic IMC principle to synthesize a nonlinear controller that involves the property of flatness. On the other hand, we propose another form of controller whose apparent structure is a PID but in which the technique of sliding modes is incorporated that will also call the nonlinear PID (NLPID). This combination has the advantage to lead to a good level of robustness provided by the sliding modes and at the same time to a good behavior specified by the PID structure. Besides, as a complement, we present two redundant controllers based on two distinct principles in order to boost and to improve the capabilities of any controller. The first one is based on the Model-Free Control (MFC) approach while the second one is based on Dynamic Sliding Mode Controller (DSMC).Finally, to highlight the performance of these controllers, we have performed a series of tests with several illustrations and scenarios and we have drawn up a comparison table with conventional approaches. The results of both the numerical simulations and the experimentation that are performed on a quadrotor are consistent and seem to be quite promising
APA, Harvard, Vancouver, ISO, and other styles
35

Hegarty-Cremer, Solene G. "Spatial control and cell guidance in evolving biological tissues." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/207246/1/Solene_Hegarty-Cremer_Thesis.pdf.

Full text
Abstract:
In this thesis, a mathematical model for tissue growth under curvature control and directed cell guidance is derived. The model extends previous mathematical work by adding a tangential cell velocity. A numerical solver is implemented to solve the model and the solutions show that new cases of tissue growth can now be simulated thanks to the extension derived in this thesis. Finally, the model is fit to data on bone pore infilling and is used to examine hypotheses about atypical tissue growth.
APA, Harvard, Vancouver, ISO, and other styles
36

Corban, J. Eric. "Real-time guidance and propulsion control for single-stage-to-orbit airbreathing vehicles." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/12889.

Full text
APA, Harvard, Vancouver, ISO, and other styles
37

Moon, Jongki. "Mission-based guidance system design for autonomous UAVs." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31797.

Full text
Abstract:
Thesis (Ph.D)--Aerospace Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Prasad, JVR; Committee Member: Costello, Mark; Committee Member: Johnson, Eric; Committee Member: Schrage, Daniel; Committee Member: Vela, Patricio. Part of the SMARTech Electronic Thesis and Dissertation Collection.
APA, Harvard, Vancouver, ISO, and other styles
38

Li, Ming-Yan. "Performance analysis and enhancement of proportional navigation guidance systems /." Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09ENS/09ensl693.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
39

Gunbatar, Yakup. "Varying Mass Missile Dynamics, Guidance &amp." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608977/index.pdf.

Full text
Abstract:
The focus of this study is to be able to control the air-to-surface missile throughout the entire flight, with emphasis on the propulsion phase to increase the impact range of the missile. A major difficulty in controlling the missile during the propulsion phase is the important change in mass of the missile. This results in sliding the center of gravity (cg) point and changing inertias. Moreover, aerodynamic coefficients and stability derivatives are not assumed to be constant at predetermined ranges
conversely, they depend on Mach number, angle of attack, and side slip angle. Consequently, as the change of missile mass, cg point, inertia terms, and stability and aerodynamic coefficients come together apart from flight operation stages, a great number of points need to be taken into account when designing the controller. This makes controlling the missile all the more complicated. In this thesis, first the equations of motion are derived, in which, mass of the missile is not assumed constant. Thus, not only the variation of mass but also the variation of inertias is incorporated in the equations of motion. From the derived v equations of motion, a nonlinear inverse dynamics controller that can achieve desired guidance for a conceptually developed air-to-surface missile has been designed, tested and verified for a modeled missile with six degrees of freedom. For brevity of the study, conceptual design and aerodynamic calculations are not given in detail. Nevertheless, improvements for conceptual design are suggested. As a result, it is shown that the controller works efficiently: the missile is able to hit the target with less than 12 m circular error of probability (CEP). Finally, studies and improvements are proposed.
APA, Harvard, Vancouver, ISO, and other styles
40

Hassoun, George Estandy. "A study of observability-enhanced guidance systems /." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phh355.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
41

Moran, Patrick J. "Control vane guidance for a ducted-fan unmanned air vehicle." Thesis, Monterey, Calif. : Springfield, Va. Naval Postgraduate School ; Available from National Technical Information Service, 1993. http://handle.dtic.mil/100.2/ADA271957.

Full text
Abstract:
Thesis (M.S. in Aeronautical Engineering) Naval Postgraduate School, June 1993.
Thesis advisor(s):Howard, Richard M. ; Shields, Michael K. "June 1993." Includes bibliographical references. Also available online.
APA, Harvard, Vancouver, ISO, and other styles
42

Jantapremjit, Pakpong. "A guidance-control approach applied to an autonomous underwater vehicle." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494914.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Roddy, D. J. "Application of optimal control to bank-to-turn CLOS guidance." Thesis, Queen's University Belfast, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373543.

Full text
APA, Harvard, Vancouver, ISO, and other styles
44

Tracy, Chisholm C. (Chisholm Cain) 1975. "Integrated entry guidance and control for autonomous reusable launch vehicles." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/8790.

Full text
Abstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1999.
Includes bibliographical references (p. 163-164).
The guidance and control approach employed on current reusable launch vehicles is based on classical control techniques developed for the Space Shuttle more than 20 years ago. This approach partitions the guidance and control tasks into separate loops resulting in a complex control architecture that can be difficult to adapt to new vehicle designs. A new entry guidance and control technique based on time-invariant linear quadratic regulator theory is presented. This approach integrates the guidance and control functions into a single multivatiable control loop that theoretically should yield improved performance over classical designs and greatly simplify the control architecture. This research is part of a larger effort to develop a next generation guidance and control system that can be implemented onboard the vehicle to increase robustness to unexpected flight conditions and abort scenarios. The integrated guidance and control algorithm is implemented in a nonlinear simulation of the Orbital Sciences X-34, a testbed for reusable launch vehicle technology. The performance and robustness of the linear quadratic regulator algorithm is compared to the classical guidance and control system developed by Orbital Sciences. The results indicate that the overall performance and robustness potential of the integrated guidance and control technique is similar to that of the classical approach. The integration of guidance, control, lateral, and longitudinal dynamics is not observed to yield significant performance improvements under the conditions tested. However, the integrated approach provides an equally effective, simplified control architecture that could allow onboard calculation of control gains in the future to yield a more robust system.
by Chisholm C. Tracy.
S.M.
APA, Harvard, Vancouver, ISO, and other styles
45

Hamel, Jean-François. "Autonomous guidance & control of earth-orbiting formation flying spacecraft." Thèse, Université de Sherbrooke, 2007. http://savoirs.usherbrooke.ca/handle/11143/1810.

Full text
Abstract:
Formation flying of spacecraft has gained a lot of interest within the engineering and scientific community in recent years. However, formation flying leads to an increased complexity of the guidance and control system, whose complexity grows rapidly with the number of spacecraft in the formation. Moreover, there is an increasing need for autonomy to decrease the cost of ground support since ground support operations are often a non-negligible part of the cost of a mission. Therefore, a formation flying guidance and control system needs to perform autonomous decisions and trade-offs in real-time to decrease the number of tasks that need to be performed by the ground segment and make formation flying affordable. This work presents the development of analytical formation flying guidance and control laws for autonomous on-board applications. Firstly, an analytical model of relative motion for elliptical and perturbed reference orbits is developed. This model is solely based on the initial orbit elements of the reference trajectory and can predict the relative motion of any spacecraft orbiting close to the reference trajectory, taking into account the secular drift caused by the J2 perturbation. Secondly, a new tool, the Fuel-Equivalent Space, is presented. The Fuel-Equivalent Space theory maps the relative orbit elements into a mathematical space where similar displacements on any axis is similar in terms of maneuvering fuel cost, therefore translating the minimum fuel problem into a simple distance minimization problem. Then, a neighbouring optimum feedback control law is developed. This feedback control law makes use of the optimal control theory to yield a semi-analytical controller that guarantees near-optimal maneuvering for any of the spacecraft orbiting close to the reference trajectory. Finally, it is shown that all these three new developments can be tied in together with simple analytical guidance laws to yield a fully autonomous guidance and control algorithm applicable to formation reconfiguration.
APA, Harvard, Vancouver, ISO, and other styles
46

Miller, Daniel(Daniel Martin). "Low-thrust Spacecraft guidance and control using proximal policy optimization." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127071.

Full text
Abstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 101-107).
Artificial intelligence is a rapidly developing field that promises to revolutionize spaceflight with greater robotic autonomy and innovative decision making. However, it remains to be determined which applications are best addressed using this new technology. In the coming decades, future spacecraft will be required to possess autonomous guidance and control in the complex, nonlinear dynamical regimes of cis-lunar space. In the realm of trajectory design, current methods struggle with local minima, and searching large solutions spaces. This thesis investigates the use of the Reinforcement Learning (RL) algorithm Proximal Policy Optimization (PPO) for solving low-thrust spacecraft guidance and control problems. First, an agent is trained to complete a 302 day mass-optimal low-thrust transfer between the Earth and Mars. This is accomplished while only providing the agent with information regarding its own state and that of Mars. By comparing these results to those generated by the Evolutionary Mission Trajectory Generator (EMTG), the optimality of the trajectory designed using PPO is assessed. Next, an agent is trained as an onboard regulator capable of correcting state errors and following pre-calculated transfers between libration point orbits. The feasibility of this method is examined by evaluating the agent's ability to correct varying levels of initial state error via Monte Carlo testing. The generalizability of the agent's control solution is appraised on three similar transfers of increasing difficulty not seen during the training process. The results show both the promise of the proposed PPO methodology and its limitations, which are discussed.
by Daniel Miller.
S.M.
S.M. Massachusetts Institute of Technology, Department of Aeronautics and Astronautics
APA, Harvard, Vancouver, ISO, and other styles
47

Thacker, Gary W., and Wayne E. Coates. "Practical Considerations of Precision Guidance and Weed Control in Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/210294.

Full text
Abstract:
This paper offers practical advice to growers interested in precision guidance technologies. Various types of guidance systems are described, along with their potential applications and benefits in a farming operation. Also discussed are some of the techniques which can be employed with precision guidance, including mechanical removal of weeds in the row, improved nutsedge control, and precision herbicide applications.
APA, Harvard, Vancouver, ISO, and other styles
48

Eng, Pillar C. S. "Path planning, guidance and control for a UAV forced landing." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/43898/1/Pillar_Eng_Thesis.pdf.

Full text
Abstract:
A forced landing is an unscheduled event in flight requiring an emergency landing, and is most commonly attributed to engine failure, failure of avionics or adverse weather. Since the ability to conduct a successful forced landing is the primary indicator for safety in the aviation industry, automating this capability for unmanned aerial vehicles (UAVs) will help facilitate their integration into, and subsequent routine operations over civilian airspace. Currently, there is no commercial system available to perform this task; however, a team at the Australian Research Centre for Aerospace Automation (ARCAA) is working towards developing such an automated forced landing system. This system, codenamed Flight Guardian, will operate onboard the aircraft and use machine vision for site identification, artificial intelligence for data assessment and evaluation, and path planning, guidance and control techniques to actualize the landing. This thesis focuses on research specific to the third category, and presents the design, testing and evaluation of a Trajectory Generation and Guidance System (TGGS) that navigates the aircraft to land at a chosen site, following an engine failure. Firstly, two algorithms are developed that adapts manned aircraft forced landing techniques to suit the UAV planning problem. Algorithm 1 allows the UAV to select a route (from a library) based on a fixed glide range and the ambient wind conditions, while Algorithm 2 uses a series of adjustable waypoints to cater for changing winds. A comparison of both algorithms in over 200 simulated forced landings found that using Algorithm 2, twice as many landings were within the designated area, with an average lateral miss distance of 200 m at the aimpoint. These results present a baseline for further refinements to the planning algorithms. A significant contribution is seen in the design of the 3-D Dubins Curves planning algorithm, which extends the elementary concepts underlying 2-D Dubins paths to account for powerless flight in three dimensions. This has also resulted in the development of new methods in testing for path traversability, in losing excess altitude, and in the actual path formation to ensure aircraft stability. Simulations using this algorithm have demonstrated lateral and vertical miss distances of under 20 m at the approach point, in wind speeds of up to 9 m/s. This is greater than a tenfold improvement on Algorithm 2 and emulates the performance of manned, powered aircraft. The lateral guidance algorithm originally developed by Park, Deyst, and How (2007) is enhanced to include wind information in the guidance logic. A simple assumption is also made that reduces the complexity of the algorithm in following a circular path, yet without sacrificing performance. Finally, a specific method of supplying the correct turning direction is also used. Simulations have shown that this new algorithm, named the Enhanced Nonlinear Guidance (ENG) algorithm, performs much better in changing winds, with cross-track errors at the approach point within 2 m, compared to over 10 m using Park's algorithm. A fourth contribution is made in designing the Flight Path Following Guidance (FPFG) algorithm, which uses path angle calculations and the MacCready theory to determine the optimal speed to fly in winds. This algorithm also uses proportional integral- derivative (PID) gain schedules to finely tune the tracking accuracies, and has demonstrated in simulation vertical miss distances of under 2 m in changing winds. A fifth contribution is made in designing the Modified Proportional Navigation (MPN) algorithm, which uses principles from proportional navigation and the ENG algorithm, as well as methods specifically its own, to calculate the required pitch to fly. This algorithm is robust to wind changes, and is easily adaptable to any aircraft type. Tracking accuracies obtained with this algorithm are also comparable to those obtained using the FPFG algorithm. For all three preceding guidance algorithms, a novel method utilising the geometric and time relationship between aircraft and path is also employed to ensure that the aircraft is still able to track the desired path to completion in strong winds, while remaining stabilised. Finally, a derived contribution is made in modifying the 3-D Dubins Curves algorithm to suit helicopter flight dynamics. This modification allows a helicopter to autonomously track both stationary and moving targets in flight, and is highly advantageous for applications such as traffic surveillance, police pursuit, security or payload delivery. Each of these achievements serves to enhance the on-board autonomy and safety of a UAV, which in turn will help facilitate the integration of UAVs into civilian airspace for a wider appreciation of the good that they can provide. The automated UAV forced landing planning and guidance strategies presented in this thesis will allow the progression of this technology from the design and developmental stages, through to a prototype system that can demonstrate its effectiveness to the UAV research and operations community.
APA, Harvard, Vancouver, ISO, and other styles
49

Baxter, Jeremy. "Fuzzy logic control of an automated guided vehicle." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5817/.

Full text
Abstract:
This thesis describes the fuzzy logic based control system for an automated guided vehicle ( AGV ) designed to navigate from one position and orientation to another while avoiding obstacles. A vehicle with an onboard computer system and a beacon based location system has been used to provide experimental confirmation of the methods proposed during this research. A simulation package has been written and used to test control techniques designed for the vehicle. A series of navigation rules based upon the vehicle's current position relative to its goal produce a fuzzy fit vector, the entries in which represent the relative importance of sets defined over all the possible output steering angles. This fuzzy fit vector is operated on by a new technique called rule spreading which ensures that all possible outputs have some activation. An obstacle avoidance controller operates from information about obstacles near to the vehicle. A method has been devised for generating obstacle avoidance sets depending on the size, shape and steering mechanism of a vehicle to enable their definition to accurately reflect the geometry and dynamic performance of the vehicle. Using a set of inhibitive rules the obstacle avoidance system compiles a mask vector which indicates the potential for a collision if each one of the possible output sets is chosen. The fuzzy fit vector is multiplied with the mask vector to produce a combined fit vector representing the relative importance of the output sets considering the demands of both navigation and obstacle avoidance. This is operated on by a newly developed windowing technique which prevents any conflicts produced by this combination leading to an undesirable output. The final fit vector is then defuzzified to give a demand steering angle for the vehicle. A separate fuzzy controller produces a demand velocity. In tests carried out in simulation and on the research vehicle it has been shown that the control system provides a successful guidance and obstacle avoidance scheme for an automated vehicle.
APA, Harvard, Vancouver, ISO, and other styles
50

Watanabe, Yoko. "Stochastically optimized monocular vision-based navigation and guidance." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22545.

Full text
Abstract:
Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Johnson, Eric; Committee Co-Chair: Calise, Anthony; Committee Member: Prasad, J.V.R.; Committee Member: Tannenbaum, Allen; Committee Member: Tsiotras, Panagiotis.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography