Rozprawy doktorskie na temat „Tracking control”
Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Tracking control.
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych rozpraw doktorskich naukowych na temat „Tracking control”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj rozprawy doktorskie z różnych dziedzin i twórz odpowiednie bibliografie.
1
Long, Matthew Robert. "Spacecraft Attitude Tracking Control". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/33843.
Pełny tekst źródłaStreszczenie:
The problem of reorienting a spacecraft to acquire a moving target is investigated. The spacecraft is modeled as a rigid body with N axisymmetric wheels controlled by axial torques, and the kinematics are represented by Modified Rodriques Parameters. The trajectory, denoted the reference trajectory, is one generated by a virtual spacecraft that is identical to the actual spacecraft. The open-loop reference attitude, angular velocity, and angular acceleration tracking commands are constructed so that the solar panel vector is perpendicular to the sun vector during the tracking maneuver. We develop a nonlinear feedback tracking control law, derived from Lyapunov stability and control theory, to provide the control torques for target tracking. The controller makes the body frame asymptotically track the reference motion when there are initial errors in the attitude and angular velocity. A spacecraft model, based on the X-ray Timing Explorer spacecraft, is used to demonstrate the effectiveness of the Lyapunov controller in tracking a given target.Master of Science
2
Ramírez, Eduardo Díaz. "A MORE EFFICIENT TRACKING SYSTEM FOR THE SANTIAGO SATELLITE TRACKING STATION". International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604559.
Pełny tekst źródłaStreszczenie:
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, NevadaA digital antenna control system has been designed and installed on a pedestal that was formerly used to drive a VHF array and that has now been replaced with an 11 meter S-Band parabolic reflector. In this Paper, the former analog tracking system will be described, showing all the drawbacks that made it unusable for S-Band. Subsequently, the development and implementation of the digital S-Band tracking system, using Labview, C++ & digital control theory will be discussed. Finally, there will be a comparison between the digital and analog system, too.
3
Sakurama, Kazunori. "Trajectory Tracking Control of Hamiltonian and Hybrid Control Systems". 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147576.
Pełny tekst źródła
4
Wang, Ning. "Model-Free Optimized Tracking Control Heuristic". Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40911.
Pełny tekst źródłaStreszczenie:
Tracking control algorithms often target the convergence of a tracking error. However, this can be at the expense of other important system characteristics, such as the control effort used to annihilate the tracking error, transient response, or steady-state characteristics, for example. Furthermore, most tracking control methods assume prior knowledge of the system dynamics, which is not always a realistic assumption, especially in the case of highly complex systems.
In this thesis, a model-free optimized tracking control architectural heuristic is proposed. The suggested feedback system is composed of two control loops. The first is the tracking loop. It focuses on the convergence of the tracking error. It is implemented using two different model-free control algorithms for comparison purpose: Reinforcement Learning (RL) and the Nonlinear Threshold Accepting (NLTA) technique. The RL scheme reformulates the tracking error combinations into a form of Markov-Decision-Process (MDP) and applies Q-Learning to build the best tracking control policy for the dynamic system under consideration. On the other hand, the NLTA algorithm is applied to tune the gains of a PID controller. The second control loop is in the form of a nonlinear state feedback loop. It is implemented using a feedforward artificial neural network (ANN) to optimize a system-wide cost function which can be flexible enough to encompass a set of desired design requirements pertaining to the targeted system behavior. This may include, for instance, the target overshoot, settling time, rise time, etc. The proposed architectural heuristic provides a model-free framework to tackle such control problems, in the sense that the plant's dynamic model is not required to be known in advance. Yet, at least a subset of the stability region of the optimized gains has to be known in advance so that it can provide a search space for the optimization algorithms. Simulation results on two dynamic systems demonstrate the superiority of the proposed control scheme.
5
Keller, Joseph J. "Tracking control of autonomous underwater vehicles". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FKeller.pdf.
Pełny tekst źródłaStreszczenie:
Thesis (Mechanical Engineer and M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2002.Thesis advisor(s): Anthony J. Healey. Includes bibliographical references (p. 67-68). Also available online.
6
Liu, Yong. "NEURAL ADAPTIVE NONLINEAR TRACKING USING TRAJECTORY LINEARIZATION". Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1177092159.
Pełny tekst źródła
7
Salai, Robert. "Tracking of Head Movements for Motion Control". Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9901.
Pełny tekst źródłaStreszczenie:
The capture of gestures in order to use them as input for intuitive control has been investigated exhaustively in recent years. However, for the most part this has resulted in relatively expensive devices. The contribution of this report is the investigation on the feasibility of the development of a low-cost vision based input device for the tracking of head movements, concerning the use of them for motion control. The input device relies on the infrared camera, along with the built-in image analysis tools, present on a Nintendo Wii remote for the measurement of the location and orientation of a head-mountable marker. The marker consists of a set of optical feature points which are easily detectable, and organized in a fashion which allows for the determination of its position and orientation in space. The developed input device was then evaluated in order to determine the operating range, accuracy and robustness, and was shown to be feasible for its intended use. Finally, the implemented device was utilized to control a mechanical output device, being a unit capable of panning and tilting.
8
Yao, Liqun. "Robust nonlinear tracking control of robotic manipulators". Thesis, University of Leicester, 1999. http://hdl.handle.net/2381/30175.
Pełny tekst źródłaStreszczenie:
This thesis has discussed the development and implementation of robust nonlinear tracking control for a parallel and serial topology Tetrahedral robot (Tetrabot), although the theoretical control strategy presented is applicable to any manipulator tracking problem. The design of robust tracking controllers involves deriving a tracking law for uncertain dynamic systems, such that the actual positions closely track desired trajectories. Two new schemes, a robust sliding mode control and a Lyapunov-based robust tracking control, have been presented for uncertain dynamical systems in the presence of model uncertainty and disturbances. The foci of this study are the concepts and techniques of robust nonlinear tracking control with a bias toward industrial applications. The Tetrabot system structure, hardware, software and the results of implementation on the three degree of freedom parallel geometry have been studied. In order to implement robust tracking control laws, the Tetrabot system software has been further developed. Most importantly, the results of implementation of a nonlinear tracking controller on the Tetrabot rig facility are also studied. To demonstrate the performance attainable by this control strategy, the trajectory involved movement across the primary working volume to the end-effect point which is the largest distance possible and involved the continuous motion; such a motion will invoke a wide range of possible nonlinear dynamic representations. The proposed control strategy is robust to variations in robot loading. The experimental results obtained for the closed-loop response indicate that compensation, which employs explicit off-line parameter estimation, can improve tracking accuracy significantly. Using the robust tracking controllers, the position errors were smaller than those obtained using the original PID controllers. The robust tracking controller showed excellent results.
9
Hitchings, Mark R., i n/a. "Distance and Tracking Control for Autonomous Vehicles". Griffith University. School of Microelectronic Engineering, 1999. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050902.084155.
Pełny tekst źródłaStreszczenie:
The author's concept of the distance and tracking control problem for autonomous vehicles relates to the cooperative behaviour of two successive vehicles travelling in the same environment. This behaviour requires one vehicle, designated the leader to move autonomously around it's environment with other vehicles, designated followers maintaining a coincident travel path and desired longitudinal distance with respect to the leader. Distance and tracking control is beneficial in numerous applications including guiding autonomous vehicles in Intelligent Transport Systems (ITS) which increases traffic safety and the capacity of pre-existing road infrastructure. Service robotics may also benefit from the cost savings and flexibility offered by distance and tracking control which enables a number of robots to cooperate together in order to achieve a task beyond the capabilities ofjust one robot. Using a distance and tracking control scheme an intelligent leader robot may guide a number of less intelligent (and therefore less costly and less complex) followers to a work-site to perform a task. The author's approach to the distance and tracking control problem consisted of two separate solutions - an initial solution used as a starting point and learning experience and a second, more robust, fuzzy control-based solution. This thesis briefly describes the initial solution, but places a greater emphasis on the second solution. The reason for this is that the fuzzy control-based solution offers significant improvement on the initial solution and was developed based on conclusions drawn from the initial solution. Most implementations of distance and tracking control, sometimes referred to as Intelligent Cruise Control (ICC) or platooning, are limited to longitudinal distance control only. The leader tracking control is performed either implicitly by a separate lane-following control system or by human drivers. The fuzzy control-based solution offered in this thesis performs both distance and tracking control of an autonomous follower vehicle with respect to a leader vehicle in front of it. It represents a simple and cost effective solution to the requirements of autonomous vehicles operating in ITS schemes - particularly close formation platooning. The follower tracks a laser signal emitted by the leader and monitors the distance to the follower at the same time using ultrasonic ranging techniques. The follower uses the data obtained from these measuring techniques as inputs to a fuzzy controller algorithm to adjust its distance and alignment with respect to the leader. Other systems employed on road vehicles utilise video-based leader tracking, or a range of lane-following methods such as magnetometer or video-based methods. Typically these methods are disadvantaged by substantial unit and/or infrastructure costs associated with their deployment. The limitations associated with the solutions presented in this thesis arise in curved trajectories at larger longitudinal distance separations between vehicles. The effects of these limitations on road vehicles has yet to be fully quantified, however it is thought that these effects would not disadvantage its use in close formation platooning. The fuzzy control-based distance and tracking control solution features two inputs, which are the distance and alignment of the follower with respect to the leader. The fuzzy controller asserts two outputs, which are left and right wheel velocities to control the speed and trajectory of a differential drive vehicle. Each of the input and output fuzzy membership functions has seven terms based around lambda, Z-type and S-type functions. The fuzzy rule base consists of 49 rules and the fuzzy inference stage is based on the MAX/MIN method. A Centre of Maximum (CoM) def'uzzification method is used to provide the two crisp valued outputs to the vehicle motion control. The methods chosen for the fuzzy control of distance and tracking for autonomous vehicles were selected based on a compromise between their computational complexity and performance characteristics. This compromise was necessary in order to implement the chosen controller structure on pre-existing hardware test beds based on an 8-bit microcontrollers with limited memory and processing resources. Overall the fuzzy control-based solution presented in this thesis effectively solves the distance and tracking control problem. The solution was applied to differential drive hardware test-beds and was tested to verify performance. The solution was thoroughly tested in both the simulation environment and on hardware test-beds. Several issues are identified in this thesis regarding the application of the solution to other platforms and road vehicle use. The solution will be shown to be directly portable to service robotics applications and, with minor modifications, applicable to road vehicle close-formation platooning.
10
Sever, Manfred D. M. "Tip velocity tracking control for elastic manipulators". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0014/NQ35318.pdf.
Pełny tekst źródła
11
Butler, Joseph MacKay. "Tracking and control in multi-function radar". Thesis, University College London (University of London), 1998. http://discovery.ucl.ac.uk/1317909/.
Pełny tekst źródłaStreszczenie:
The phased array multi-function radar is an effective solution to the requirement for simultaneous surveillance and multiple target tracking. However, since it is performing the jobs usually undertaken by several dedicated radars its radar time and energy resources are limited. For this reason, and also due to the large cost of active phased array antennas, it is important for the strategies adopted in the control of the radar to be efficient. This thesis investigates and develops efficient strategies for multi-function radar control and tracking. Particularly the research has focused on the use of rotating array antennas and simultaneous multiple receive beam processing. The findings of the research challenge the traditional view that three or four fixed (static) array faces is the best antenna configuration for a multi-function radar system. By developing novel methods for the comparison of systems utilising different antenna configurations it is shown that a rotating array multi-function radar performs the surveillance function with a greater efficiency in its use of radar time than a static array system. Also, a rotating array system benefits from the ability to distribute the radar resources over the angular coverage in a way that is impossible with a static array system. A novel strategy is presented to achieve this, which allows the rotating array system to better support the realistic situation of a high concentration of radar tasks in a narrow angular sector. It is shown that the use of broadened transmit beams coupled with simultaneous multiple narrow receive beams can eliminate the compromise on radar beamwidth between the surveillance and tracking functions that is associated with multi-function radars. This technique would allow construction of multi-function radar systems with narrow beamwidths, giving improved tracking performance, without extending search frame times excessively. Efficient tracking strategies for both static array and rotating array multi-function radars are developed. They are applied through computer simulation to demonstrate tracking of highly manoeuvrable targets with a narrow beam multi-function radar. Track robustness is attained through the use of multiple beam track updating strategies at little cost in terms of radar time.
12
Turner, P. J. "Tracking control of a direct-drive robot". Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/46838.
Pełny tekst źródła
13
Miller, James J., i Philip H. Tannenholz. "AN IMPROVED DRONE TRACKING CONTROL SYSTEM TRANSPONDER". International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613789.
Pełny tekst źródłaStreszczenie:
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaImproved performance has been achieved in the new Herley design of the Model MD700C-1 Drone Tracking and Control System, C-band Command and Control Transponder. The approach for obtaining better radio frequency rejection, automatic gain control, local oscillator stability, and power supply efficiency is described. New hybrid microwave integrated circuit application techniques were used to design a small local oscillator, tunable over the 5400 to 5900 MHz range with a frequency drift of less than ± 1 MHz. This low frequency drift allowed the use of a 4 pole immediate amplifier filter, 60 dB down, at 40 MHz bandwidth, which, when coupled with the three cavity radio frequency preselector filter, provides 7 pole out of band rejection for unwanted radar signals operating at close frequencies. To augment the out of band rejection, a new form of 75 dB dynamic range automatic gain control was used, which combines signal attenuation with a circuit that reduces immediate frequency noise with increasing signal. This allows rejection of the radars own in-band multipath signals by reducing the gain and threshold sensitivity. To reduce power consumption and heat while operating over a wide voltage range, a switching mode regulator and a nonsaturating core power supply was designed to operate at 80% efficiency. Compared to units in field use over the past 10 years, the new design shows improvements of 400 percent in local oscillator frequency stability, 30 percent in out of band frequency rejection, 66 percent in the automatic gain control dynamic range, and 60 percent in power supply efficiency. The MD700C-1 was developed by Herley Industries for the USAF SMALC, and is currently in production.
14
Chen, Yiyang. "Iterative learning control for spatial path tracking". Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/415865/.
Pełny tekst źródłaStreszczenie:
Iterative learning control (ILC) is a high performance method for systems operating in a repetitive manner, which aims to improve tracking performance by learning from previous trial information. In recent years research interest has focused on generalizing the task description in order to achieve greater performance and flexibility. In particular, researchers have addressed the ease of tracking only at a single, or a collection of time instants. However, there still remain substantial open problems, such as the choice of the time instants, the need for system constraint handling, and the ability to release explicit dependence on time. A number of ILC methods have tackled the latter problem, loosely termed spatial ILC, but are all application specific and limited in scope. The aim of this thesis is to unlock this potential, and the specific contributions are as follows: first a mechanism to optimize the time instants at the critical tracking positions within point-to-point tracking is developed. This is achieved by embedding an additional cost function and deriving a ‘Two Stage’ design framework to yield an iterative algorithm which minimizes control effort as well as guaranteeing high performance tracking. This approach is based on norm optimal ILC and gradient minimization. Then the task description is further generalized by expanding the formulation to embed via-point constraint and linear planar constraints. This embeds the incorporation of various design objectives including spatial path tracking in a general class of systems, and a mixed form of system constraints are added into this framework. An algorithmic ILC solution is derived using the successive projection method to achieve high performance tracking of the design objectives. Finally, the Two Stage design framework and the generalized ILC framework are combined together to yield the first spatial ILC algorithm capable of optimizing an additional cost function whilst completing the spatial path tracking objective for a general class of systems. All proposed algorithms are verified experimentally on a gantry robot platform, whose experimental results demonstrate their practical efficacy and ability to substantially widen the scope of the current ILC framework.
15
Hitchings, Mark. "Distance and Tracking Control for Autonomous Vehicles". Thesis, Griffith University, 1999. http://hdl.handle.net/10072/366396.
Pełny tekst źródłaStreszczenie:
The author's concept of the distance and tracking control problem for autonomous vehicles relates to the cooperative behaviour of two successive vehicles travelling in the same environment. This behaviour requires one vehicle, designated the leader to move autonomously around it's environment with other vehicles, designated followers maintaining a coincident travel path and desired longitudinal distance with respect to the leader. Distance and tracking control is beneficial in numerous applications including guiding autonomous vehicles in Intelligent Transport Systems (ITS) which increases traffic safety and the capacity of pre-existing road infrastructure. Service robotics may also benefit from the cost savings and flexibility offered by distance and tracking control which enables a number of robots to cooperate together in order to achieve a task beyond the capabilities ofjust one robot. Using a distance and tracking control scheme an intelligent leader robot may guide a number of less intelligent (and therefore less costly and less complex) followers to a work-site to perform a task. The author's approach to the distance and tracking control problem consisted of two separate solutions - an initial solution used as a starting point and learning experience and a second, more robust, fuzzy control-based solution. This thesis briefly describes the initial solution, but places a greater emphasis on the second solution. The reason for this is that the fuzzy control-based solution offers significant improvement on the initial solution and was developed based on conclusions drawn from the initial solution. Most implementations of distance and tracking control, sometimes referred to as Intelligent Cruise Control (ICC) or platooning, are limited to longitudinal distance control only. The leader tracking control is performed either implicitly by a separate lane-following control system or by human drivers. The fuzzy control-based solution offered in this thesis performs both distance and tracking control of an autonomous follower vehicle with respect to a leader vehicle in front of it. It represents a simple and cost effective solution to the requirements of autonomous vehicles operating in ITS schemes - particularly close formation platooning. The follower tracks a laser signal emitted by the leader and monitors the distance to the follower at the same time using ultrasonic ranging techniques. The follower uses the data obtained from these measuring techniques as inputs to a fuzzy controller algorithm to adjust its distance and alignment with respect to the leader. Other systems employed on road vehicles utilise video-based leader tracking, or a range of lane-following methods such as magnetometer or video-based methods. Typically these methods are disadvantaged by substantial unit and/or infrastructure costs associated with their deployment. The limitations associated with the solutions presented in this thesis arise in curved trajectories at larger longitudinal distance separations between vehicles. The effects of these limitations on road vehicles has yet to be fully quantified, however it is thought that these effects would not disadvantage its use in close formation platooning. The fuzzy control-based distance and tracking control solution features two inputs, which are the distance and alignment of the follower with respect to the leader. The fuzzy controller asserts two outputs, which are left and right wheel velocities to control the speed and trajectory of a differential drive vehicle. Each of the input and output fuzzy membership functions has seven terms based around lambda, Z-type and S-type functions. The fuzzy rule base consists of 49 rules and the fuzzy inference stage is based on the MAX/MIN method. A Centre of Maximum (CoM) def'uzzification method is used to provide the two crisp valued outputs to the vehicle motion control. The methods chosen for the fuzzy control of distance and tracking for autonomous vehicles were selected based on a compromise between their computational complexity and performance characteristics. This compromise was necessary in order to implement the chosen controller structure on pre-existing hardware test beds based on an 8-bit microcontrollers with limited memory and processing resources. Overall the fuzzy control-based solution presented in this thesis effectively solves the distance and tracking control problem. The solution was applied to differential drive hardware test-beds and was tested to verify performance. The solution was thoroughly tested in both the simulation environment and on hardware test-beds. Several issues are identified in this thesis regarding the application of the solution to other platforms and road vehicle use. The solution will be shown to be directly portable to service robotics applications and, with minor modifications, applicable to road vehicle close-formation platooning.Thesis (Masters)
Master of Philosophy (MPhil)
School of Microelectronic Engineering
Science, Environment, Engineering and Technology
Full Text
16
Simon, Daniel. "Model Predictive Control in Flight Control Design : Stability and Reference Tracking". Licentiate thesis, Linköpings universitet, Reglerteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-103742.
Pełny tekst źródłaStreszczenie:
Aircraft are dynamic systems that naturally contain a variety of constraints and nonlinearities such as, e.g., maximum permissible load factor, angle of attack and control surface deflections. Taking these limitations into account in the design of control systems are becoming increasingly important as the performance and complexity of the controlled systems is constantly increasing. It is especially important in the design of control systems for fighter aircraft. These require maximum control performance in order to have the upper hand in a dogfight or when they have to outmaneuver an enemy missile. Therefore pilots often maneuver the aircraft very close to the limit of what it is capable of, and an automatic system (called flight envelope protection system) against violating the restrictions is a necessity. In other application areas, nonlinear optimal control methods have been successfully used to solve this but in the aeronautical industry, these methods have not yet been established. One of the more popular methods that are well suited to handle constraints is Model Predictive Control (MPC) and it is used extensively in areas such as the process industry and the refinery industry. Model predictive control means in practice that the control system iteratively solves an advanced optimization problem based on a prediction of the aircraft's future movements in order to calculate the optimal control signal. The aircraft's operating limitations will then be constraints in the optimization problem. In this thesis, we explore model predictive control and derive two fast, low complexity algorithms, one for guaranteed stability and feasibility of nonlinear systems and one for reference tracking for linear systems. In reference tracking model predictive control for linear systems we build on the dual mode formulation of MPC and our goal is to make minimal changes to this framework, in order to develop a reference tracking algorithm with guaranteed stability and low complexity suitable for implementation in real time safety critical systems. To reduce the computational burden of nonlinear model predictive control several methods to approximate the nonlinear constraints have been proposed in the literature, many working in an ad hoc fashion, resulting in conservatism, or worse, inability to guarantee recursive feasibility. Also several methods work in an iterative manner which can be quit time consuming making them inappropriate for fast real time applications. In this thesis we propose a method to handle the nonlinear constraints, using a set of dynamically generated local inner polytopic approximations. The main benefits of the proposed method is that while computationally cheap it still can guarantee recursive feasibility and convergence.The series name "Linköping studies in science and technology. Licentiate Thesis" is incorrect. The correct series name is "Linköping studies in science and technology. Thesis".
17
Callantine, Todd Jeffrey. "Tracking operator activities in complex systems". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/31091.
Pełny tekst źródła
18
Veibäck, Clas. "Tracking of Animals Using Airborne Cameras". Licentiate thesis, Linköpings universitet, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-132426.
Pełny tekst źródłaStreszczenie:
The various elements of a modern target tracking framework are covered. Background theory on pre-processing, modelling and estimation is presented as well as some novel ideas on the topic by the author. In addition, a few applications are posed as target tracking problems for which solutions are gradually constructed as relevant theory is covered. Among considered problems are how to constrain targets to a region, use state-independent measurements to improve estimation in jump Markov models and how to incorporate observations sampled at an uncertain time into a state-space model. A framework is developed for tracking dolphins constrained to a basin using an overhead camera that suffers from occlusions. In this scenario, conventional motion models would suffer from infeasible predictions outside the basin. A motion model is developed for the dolphins where collisions with nearby walls are avoided by turning. The basin is modelled as a polygon where each point along the edge influences the turn rate of the dolphin. The proposed model results in predictions inside the basin, increasing robustness against occlusions. An extension to a Gaussian mixture background model providing a degree of confidence for detections is used to improve tracking in the presence of shadows. A probabilistic data association filter is also modified to estimate the dolphin extension as an ellipse. The proposed framework is able to maintain tracks through occlusions and poor light conditions. A framework is developed for estimating takeoff times and directions of birds in circular cages using an overhead camera. A jump Markov model is used to model the stationary and flight behaviours of the birds. A proposed extension also incorporates state-independent measurements, such as blurriness, to improve mode estimation. Takeoff times and directions are estimated from mode transitions and results are compared to manually annotated data. The cameras are inaccessible in both applications, disallowing proper calibrations. As an alternative, a method is proposed to estimate stationary camera models from available data and known features in the scene. A map of the basin and the funnel dimensions are used respectively. The method estimates a homography and distortion parameters in an invertible mapping function. An extension to the linear Gaussian state-space models is proposed, incorporating an additional observation with an uncertain timestamp. The posterior distribution of the states is derived for the model, which is shown to be a mixture of Gaussians, as well as some estimators for the distribution. The effects of incorporating the observation with an uncertain timestamp into the model are analysed for a one-dimensional scenario. The model is also applied to improve the GPS position of an orienteering sprinter by using the control position as an observation with an uncertain timestamp.LINK-SIC
19
Hawkins, G. J. "Control techniques for electronic beam squint tracking systems". Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339823.
Pełny tekst źródła
20
Best, Robert Andrew. "Integrated tracking and guidance". Thesis, University of Birmingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322491.
Pełny tekst źródła
21
Damweber, Michael Frank. "Model independent offset tracking with virtual feature points". Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/17651.
Pełny tekst źródła
22
Sato, Kazuhiro. "An Algebraic Analysis Approach to Trajectory Tracking Control". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188865.
Pełny tekst źródła
23
Ke, Zhenqing. "Sampled-data control: stabilization, tracking and disturbance rejection". Thesis, University of Bath, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492283.
Pełny tekst źródła
24
Shahzad, Muhammad Imran, i Saqib Mehmood. "Control of Articulated Robot Arm by Eye Tracking". Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3096.
Pełny tekst źródłaStreszczenie:
Eye tracking has many comprehensive achievements in the field of human computer interaction. Uses of human eyes as an alternative of hands are an innovative way in the human computer interaction perspective. Many application of autonomous robot control has already been developed, but we developed two different interfaces to control the articulated robot manually. The first of these interfaces is controlled by mouse and the second is controlled by eye tracking. Main focus of our thesis is to facilitate the people with motor disabilities by using their eye as an input instead of a mouse. Eye gaze tracking technique is used to send commands to perform different tasks. Interfaces are divided into different active and inactive regions. Dwell time is a well known technique which is used to execute commands through eye gaze instead of using a mouse. When a user gazes in an active region for a specific dwell time, the command is executed and the robot performs a specific task. When inactive regions are gazed at, there no command execution and no function are performed. The difference between time of performing the task by mouse and Eyetracking is shown to be 40 ms, the mouse being faster. However, a mouse cannot be used for people with motor disabilities, so the Eyetracker in this case has a decisive advantage. Keywords: Eyetracking, Interface, Articulated robot
25
Pourbohloul, Babak. "Control and tracking of chaos in Hamiltonian systems". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0007/NQ43106.pdf.
Pełny tekst źródła
26
Garg, Aditya. "Adaptive and optimal tracking control of electromechanical servosystems". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ63307.pdf.
Pełny tekst źródła
27
Mouri, Richard I. "The facilities automated control and tracking system (FACTS)". Master's thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-01202010-020124/.
Pełny tekst źródła
28
Mansoori, Nasser. "Tracking of time-varying parameters in self-tuning control". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315646.
Pełny tekst źródła
29
Petropoulakis, L. "Design of digital trajectory tracking systems for robotic manipulators". Thesis, University of Salford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384976.
Pełny tekst źródła
30
Cooper, David Maurice. "Nonlinear tracking by trajectory regulation control using backstepping method". Ohio : Ohio University, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1125370268.
Pełny tekst źródła
31
Erlandsson, Tina. "Angle-Only Target Tracking". Thesis, Linköping University, Department of Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8537.
Pełny tekst źródłaStreszczenie:
In angle-only target tracking the aim is to estimate the state of a target with use of measurement of elevation and azimuth. The state consists of relative position and velocity between the target and the platform. The platform is an Unmanned Aerial Vehicle (UAV) and the tracking system is meant to be a part of the platform’s anti-collision system. In the case where both the target and the platform travel with constant velocity the angle measurements do not provide any information of the range between the target and the platform. The platform has to maneuver to be able to estimate the range to the target.
Two filters are implemented and tested on simulated data. The first filter is based on a Extended Kalman Filter (EKF) and is designed for tracking nonmaneuvering targets. Different platform maneuvers are studied and the influence of initial errors and the geometry of the simulation scenario is investigated. The filter is able to estimate the position of the target if the platform maneuvers and the target travels with constant velocity. Maneuvering targets on the other hand can not be tracked by the filter.
The second filter is an interacting multiple model (IMM) filter, designed for tracking maneuvering targets. The filter performance is highly dependent of the geometry of the scenario. The filter has been tuned for a scenario where the target approaches the platform from the front. In this scenario the filter is able to track both maneuvering and non-maneuvering targets. If the target approaches the platform from the side on the other hand, the filter has problems with distinguish target maneuvers from measurement noise.
32
Streich, Ronald G., i Charles R. Townsend. "Windows at a Tracking Site". International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/611864.
Pełny tekst źródłaStreszczenie:
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, NevadaRapid setup and verification of 4 automatic tracking antennas, 2 radio frequency switch matrixes, 32 telemetry receivers with 16 diversity combiners, an intermediate frequency switch matrix and the signal distribution equipment interface to the analog and digital fiber optic relay systems was required. This paper provides sample displays of the station status window, telemetry receiver and test parameter dialog boxes, mission event log window and test result windows for bit error rate, noise power ratio, solar calibration and antenna servo tests. Use of the software is apparent from sample displays so the text concentrates on lessons learned from site surveys, verification of configuration against mission files, accommodation of change of plug-in modules (e.g., IF filters in the telemetry receiver), tolerance of equipment removed from the system for maintenance, built-in test of serial and parallel communications and modular software design for replacement of equipment.
33
Xiao, Weidong. "Improved control of photovoltaic interfaces". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2393.
Pełny tekst źródłaStreszczenie:
Photovoltaic (solar electric) technology has shown significant potential as a source of practical and sustainable energy; this study focuses on increasing the performance of photovoltaic systems through the use of improved control and power interfaces. The main objective is to find an effective control algorithm and topology that are optimally suited to extracting the maximum power possible from photovoltaic modules. The thesis consists of the following primary subjects: photovoltaic modelling, the topological study of photovoltaic interfaces, the regulation of photovoltaic voltage, and maximum power tracking.
In photovoltaic power systems both photovoltaic modules and switching mode converters present non-linear and time-variant characteristics, resulting in a difficult control problem. This study applies in-depth modelling and analysis to quantify these inherent characteristics,s pecifically using successive linearization to create a simplified linear problem. Additionally, Youla Parameterisation is employed to design a stable control system for regulating the photovoltaic voltage. Finally, the thesis focuses on two critical aspects to improve the performance of maximum power point tracking. One improvement is to accurately locate the position of the maximum power point by using centred differentiation. The second is to reduce the oscillation around the steady-state maximum power point by controlling active perturbations. Adopting the method of steepest descent for maximum power point tracking, which delivers faster dynamic response and a smoother steady-state than the hill climbing method, enables these improvements. Comprehensive experimental evaluations have successfully illustrated the effectiveness of the proposed algorithms. Experimental evaluations show that the proposed control algorithm harvests about 1% more energy than the traditional method under the same evaluation platform and weather conditions without increasing the complexity of the hardware.
34
Hyllengren, Jonas. "Clustering for Multi-Target Tracking". Thesis, Linköpings universitet, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-143807.
Pełny tekst źródłaStreszczenie:
This thesis presents a clustering-based approach to decrease the computational cost of data association in multi-target tracking. This is achieved by clustering the sensor tracks using approximate distance functions, thereby decreasing the number of possible associations and the need to calculate expensive statistical distances between tracks. The studied tracking problem includes passive and active sensors with built-in filters. Statistical and non-statistical distance functions were designed to account for the characteristics of the different combinations of sensors. The computational cost and accuracy of these distance functions were evaluated and compared. Analysis is done in a simulated environment with randomly positioned targets and sensors. Simulations show that there are approximate distances with a cost of calculation ten times cheaper than the true statistical distance, with only minor drops in accuracy. Spectral clustering is used on these distances to divide complex association problems into sub-problems. This algorithm is evaluated on a large number of random scenarios. The mean size of the largest sub-problem is 40 % of the original, and the mean number of errors in the clustering is 5 %.
35
Lu, Chi-Chiuan, i 爐啟銓. "Robust Fuzzy Tracking control". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/s3v5tf.
Pełny tekst źródłaStreszczenie:
碩士國立高雄應用科技大學
電機工程系博碩士班
96
This issue of robust fuzzy control of T-S fuzzy systems is studied in the thesis. For the cases of systems with and without disturbance and uncertainties, the state-feedback fuzzy tracking controllers are designed respectively. All the designed conditions are expressed in the form of LMIs, thus they are numerically realizable. From the simulations of examples, it can be seen that the proposed approach achieves a better tracking performance in comparison with existing literature.
36
Hung, Je-Bin, i 洪哲彬. "Tracking Control of Engine Valve". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/13802873120194995864.
Pełny tekst źródłaStreszczenie:
碩士國立臺灣大學
機械工程學研究所
95
The intake/exhaust valve is driven by the camshaft with constant angular velocity while the spark-ignition engine is in operation. Hence, the opening/closing timing of valves is unable to adjust according to engine speed. As a result, the engine has optimum efficiency only at certain engine speeds. Variable valve timing system can change the timing of valve in compliance with the engine speed so that engine’s optimal efficiency can be maintained at all speed. Research shows that such a proved effective for improving engine performance and fuel economy. In this thesis, we propose a new method to implement variable valve timing by positioning the angular position of camshaft. The camshaft then drives the valve to track designed trajectory. The method can eliminate the valve impact on its seating that occurs in electromagnetic engine valve. Moreover, it is able to reduce wear and acoustic noise.
37
Hung, Je-Bin. "Tracking Control of Engine Valve". 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-0507200717091900.
Pełny tekst źródła
38
Lee, jiann bang, i 李建邦. "Pressure tracking control of a pneumatic control system". Thesis, 1998. http://ndltd.ncl.edu.tw/handle/34913924192704550578.
Pełny tekst źródłaStreszczenie:
碩士國立成功大學
機械工程學系
86
Because of the high compressibility of air, it is very difficult to obtain the precise mathematical model of pneumatic control system. The fuzzy logic control and the neural network theories have been developed in the recent decades. By means of applying the fuzzy logic control theory to design a controller whose mathematical model of the system is not necessary, and the neural network has the ability of learning. Therefor, it is very suitable to apply the intelligent control theory which combines the fuzzyThis paper presents an on-line neural fuzzy controller to control the preesure of a pneumatic cylinder. According to the system output and input relation The learning rate can adjust by itself for increasing learning efficiency. A pressure reducing valve is often used in traditional pneumatic pressure control system, this paper compares servo valve and proportion valve to control pneumatic pressure system. According to the experimental data, the neural fuzzy controller has good accuracy in pressure control in each case.
39
"On tracking a deterministic growth". 2003. http://library.cuhk.edu.hk/record=b5891656.
Pełny tekst źródłaStreszczenie:
Zhang Li.Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references (leaves 67-69).
Abstracts in English and Chinese.
Chapter 1 --- Introduction and Literature Review --- p.1
Chapter 2 --- The Tracking Portfolio Models --- p.7
Chapter 2.1 --- Problem Formulation --- p.8
Chapter 2.2 --- Reformulation of Tracking Models --- p.12
Chapter 2.3 --- A Stochastic LQ Control Approach --- p.13
Chapter 3 --- Efficient Tracking: Deterministic Market Parameters --- p.16
Chapter 3.1 --- Solution to Model I --- p.17
Chapter 3.2 --- A Special Case of Model I --- p.23
Chapter 3.3 --- Solution to Model II --- p.24
Chapter 3.4 --- A Special Case of Model II: Mean-Variance Portfolio Selection --- p.32
Chapter 3.5 --- Solution to Model III --- p.36
Chapter 4 --- Efficient Tracking: Markov-Modulated Market Parameters --- p.41
Chapter 4.1 --- Problem Formulation --- p.42
Chapter 4.2 --- Solution to Model I with Regime Switching --- p.47
Chapter 4.3 --- Solution to Model II with Regime Switching --- p.52
Chapter 4.4 --- Solution to Model III with Regime Switching --- p.59
Chapter 5 --- Conclusion --- p.64
Bibliography --- p.66
40
HSIAO, YUNG-LONG, i 蕭永隆. "Trajectory Tracking Control of Redundant Manipulators". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/16641495572540039537.
Pełny tekst źródła
41
Lai, Hrong Ren, i 賴鴻仁. "Trajectory Tracking Control of Articulated Manipulators". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/48705108583414256905.
Pełny tekst źródła
42
Wang, Wen-Yu, i 王文裕. "Vehicle Tracking Control Using Image Detection". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/u33rh4.
Pełny tekst źródłaStreszczenie:
碩士國立臺灣科技大學
機械工程系
95
This thesis studies the problem of controlling a model tank using direct image processing feedback and fuzzy logic to achieve a real time image-based unmanned vehicle tracking system. To implement the tracking control of the model vehicle, a CCD camera is mounted on the vehicle and images form the camera are processed by conventional image processing techniques such as Binary Image, Median Filter to separate the desired track line from the background. The pixels from the processed track line are then approximated as a straight line mathematical model using curve fitting, and the distance and heading errors between the tank position and the desired track objective can be deriver from the line model. The distance and heading errors are then used as inputs to fuzzy logic controller to generate control outputs. To recode and analyze the resulting tracking error, another camera is mounted on the ceiling to recode the vehicle path and desired track. The experiment results show that the controlled vehicle can achieve less than 2 centimeters during straight line tracks and for U-shape tracks the tracking errors as less than 6 centimeters.
43
Lin, Shyh-Woei, i 林世偉. "Adaptive Tracking Control for Robotic Manipulators". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/80160875331280215191.
Pełny tekst źródłaStreszczenie:
碩士中原大學
機械工程研究所
82
The various control algorithms have been proposed to resolve variant control problems of robotics manipulator in many references. Generally, robotic controller design are based on the analysis of robotic system dynamics. In the presence of uncertainty on the mass properties of the load or its exact position in the end-effector, have spurred a large body of literature on the adaptive control of robotic manipulators. The nonlinearity of robot dymanics, makes them even more complex to analyze than the linear dynamic systems on which most of the existing adaptive controltheory has been traditionally focused. Robotic dynamic equations are derived by using Denavit-Hart- enberg Representation and presented in this paper. The adaptive control technique are used in building robot controller. From the system input and output dynamics relation, we could estimate the unknown parameters. The persistence excitation condition are derived by using the least-squares with exponential forgetting factor method. By using the Lyapunov global stability theorem, we obtain the control law and the adaptive law in fitting this system. The adaptive controller is tested by computer simulatio- ns for a four degrees of freedom robot. During simulation process, the controller drives robot to track a given trajectory while it carries an uncertain payload under the persistent excitation condition. The results show control algorithms performs its function and parameters estimated error tend to zero in accordance with our design. From the results we conclude that a control structure could well serve in working environment. Because of its simplicity, this methodology is also able to extend directly to incorporate other control algorithms.
44
Wang, Yu-Hsiang, i 王譽翔. "Design of 2DOF Object-Tracking Control". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/41865796473578658691.
Pełny tekst źródłaStreszczenie:
碩士中原大學
機械工程研究所
94
In this thesis, the primary target is to design a capable following control method implemented on the associated robotic-manipulator system for load/unload process of the electro-plating system in IC packaging application. Servo motor is employed for each axis of the manipulator system. The cogging force generated during of motor and the phase lag apparent in closed-loop system affect the motion velocity and positioning precision. Therefore, a disturbance observer is designed in the velocity loop of the control system to reduce the effect of cogging force. Besides, a PD controller in the position loop is designed for an asymptotically stable system. Since the high-frequency cogging force can not be rejected effectively by the disturbance observer alone, and causes a chattering phenomenon, a repetitive controller is considered to enhance the performance of disturbance rejection. For the phase lag rejection, a zero phase error tracking controller is added as a feedforward controller in the feedback control system. Such a control system is robust to disturbance and efficient to reduction phase lag so as to have better tracking performance. For practical load/unload application in the electro-plating system, the positioning error needs to be less than 100μm at the motor speed of 3000rpm. From the experimental data, the developed system is able to achive the purpose of disturbance rejection and phase lag rejection, and the positioning error is less than 10μm under the operating speed of 3000 rpm, which outperforms the desired accurcy.
45
Chang, Shu-Min, i 張樹銘. "Implementation of High Speed Tracking Control". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/63811824966071188219.
Pełny tekst źródłaStreszczenie:
碩士國立中山大學
機械工程學系研究所
88
As the electronic products are getting more and more small, the trend of the needs for speed and accuracy is more precise. Therefore, upgrading the speed and the accuracy of contour error on tracking control has become an important point. This research is focus on the improving of contour error and terminus error. In the contour error, we design the acceleration /deceleration profile based on digital FIR filter. And then remodel the compensatory method of cross-coupled controller, making the design of controller parameter easier, and getting better efficiency. And further, we get the time-variable gain by curve of contour error, making the accuracy better. In terminus error, according to two-step control, we switch the controller in deceleration region, not only directly improving the terminus error, but also improving the contour error. Finally, the above improved strategies are verified by the simulation and experimental results.
46
Cheng, Chih-Hsien, i 鄭志先. "Tracking Control of Electro-Hydraulic System". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/83761902657725486395.
Pełny tekst źródłaStreszczenie:
碩士國立高雄應用科技大學
機械與精密工程研究所
97
This thesis presents the derivation, and simulation of a nonlinear tracking control for an electro-hydraulic system, as these devises must often follow prescribed motions. An analysis of nonlinear system equation is used in the derivation of a singular perturbed function that provides for exponentially stable force trajectory tracking. This control law is extended to provide position tracking, and employed hydraulic fluid bulk modulus a difficult to characterize quantity as a parameter. To overcome the difficulty, we have developed a controller design procedure that required no additional sensors, and is robust to variations in the bulk modulus. A dual approach of singular perturbation theory and Lyapunov techniques from the basis for the procedure. The simulation results show that the proposed derivation singular perturbed function and controller design will track a given smooth trajectory with small error.
47
Lu, Chen, i 呂戰. "Tracking Control of Remotely Operated Vehicle". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/21976863067085421181.
Pełny tekst źródłaStreszczenie:
碩士國立海洋大學
機械與輪機工程學系
85
Dynamics of a Remotely Operated Vehicle (R.O.V.) propelled by a pair of -ters and rudders for plannar motion and a pair of thrusters in the verticaldirection is described. To achieve tracking control,fuzzy controllers were pro-posed for motion control and a bearing-only method based on Modified Polar coor- dinate was used for position estimation. Simulation was conducted to verify thefeasibility of this closed loop control algorithem. Based on the assumption that the roll and pith motions are negligible, theplannar motion and the vertical motion are decoupled. Fuzzy controllers were designed for the plannar and the vertical motions, respectively. The plannar motion control was further divided into thruster control and rudder control. Position and velocity errors between R.O.V. and the moving reference input were used for thruster cintrol. Bearing angle difference between R.O.V. heading and the moving direction of reference input was used for rudder control. To simplify the under-water position estimation, a bearing-only trackingtechnique was employed. The conditions for observability of this observer weresummaried
48
Yao, Kun-Ciang, i 姚焜強. "Lean Production Tracking and Control System". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/75806448158641904541.
Pełny tekst źródłaStreszczenie:
碩士國立雲林科技大學
工業工程與管理研究所碩士班
101
Lean Production and push production are two major manufacturing types, but lean production cannot employ push systems directly because of the fundamental differences in planning philosophy. Push production representative systems is enterprise resource planning system (ERP) system, it can control production, finance and other function of the management cycle. Lean production emphasizes jidoka and visual management, and information transmission is by kanban and operators. Mostly information systems are manufacturers'' individual development. So lean production for computerization slower than push production. Some manufacturers choose to push production, it because of information technology. The purpose of this research is to discuss the combination of push and lean systems in the context of enterprise resource planning system (ERP). We developed a lean shop floor tracking and rooted it in an ERP, so ERP can apply to both push and lean industries. This system can be better by two function, the first can using genetic algorithm plan to number of kanban, another can getting performance for shipping planning by simulation. We present a solar-photonics silicon-cell case study to demonstrate the combination, and planning number of kanban. Four conclusions are drawn from this research: (1) push and lean production can be well managed in an ERP system simultaneously with an extended design, (2) Lean shop floor tracking system and ERP can benefit the lean industries by fast computerization to improve its operations, and benefit the current ERP users by offering an option to change to lean production, partially or overall, to gain the capability of responding to markets quickly, (3) Lean shop floor tracking system combines lean simulation system function and parameter optimization to improve the feasibility of the implementation of lean production, (4) ERP vendors will have the opportunity to enter the Lean Enterprise, opening up new applications.
49
I-ChenLin i 林宜臻. "Age-related differences in dynamic force control: pursuit tracking and compensatory tracking". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/qzss6s.
Pełny tekst źródłaStreszczenie:
碩士國立成功大學
物理治療學系
105
Objective: There are two major forms of visuomotor tracking, compensatory and pursuit tracking. The former tracking is to counter virtual perturbation in need of closed-loop control, while the later entails to couple movement output to a moving target with a predictable trajectory. Central processing of visual feedback have been proved to degenerate with aging that causes changes in structure of movement variability. The age-related changes in force behaviors reflect a selective decline in the feedback and feedforward processes for force control with aging. The purpose of the present study was to investigate the age-related differences in force fluctuation properties between the conditions of compensatory tracking and pursuit tracking. Methods: 17 young health adults (23.0 ± 2.3) and 17 older health adults (68.4 ± 7.3) participated in the study. All participants were required to exert a load-varying isometric force to couple 0.2 Hz sinusoidal target wave in the range of 9%–11% MVC of index abduction of right first dorsal interosseus in pursuit tracking. The participants stabilized the target movement on the monitor at a constant level of 10% MVC, by resisting sinusoidal virtual perturbation during compensatory tracking. Normalized changes in force behaviors and force fluctuation properties between compensatory tracking and pursuit tracking for the two populations were contrasted. Results: The results of the study indicated that normalized difference in force fluctuations of the older adults was significantly greater than that of the young adults. In addition, the normalized difference in SampEn of the older adults was significantly greater than that of the young adults. Other force fluctuation properties in ratio of residual power, task error, correlation between the target and force trajectory and peak amplitude did not significantly differ with the older and the young adults. Conclusions: In summary, older adults had more force variability in visuomotor tasks by virtue of the differential age effect on force characteristics for the two tracking patterns. The greater normalized change in the size of force fluctuations for the elderly indicated the elderly were more variable in force control than young adults, when tracking task shifts from pursuit modes to compensatory mode. In addition, the less normalized change in the complexity of force fluctuations for the aged symbolized the aged exhibited a more regular force fluctuations than the young, when tracking task shifts from compensatory modes to pursuit modes. Thus, the provision of feedback-based visuomotor practice to the elderly should be aware of the fact that degenerative changes in feedback control could destabilize force output with less strategic richness for a visuomotor task.
50
You, Sheng-Jhong, i 游昇忠. "Visual Trajectory Tracking Control of Quadrotor Using Fuzzy Control Method". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/48385833916494899615.
Pełny tekst źródłaStreszczenie:
碩士國立宜蘭大學
機械與機電工程學系碩士班
103
The purpose of this study is to design a quadrotor’s control system, which is able to autonomously adjust the attitude and track the position of the quadrotor. The control system is composed of three parts: the attitude controller, the image recognition system and the position controller. The attitude controller is designed to automatically correct the flight angle of quadrotor with disturbance. Inertial Measurement Unit (IMU) is employed to measure the current flight attitude, and a PID controller is designed to control the motor speed so that the flight angle of quadrotor can be automatically corrected. For easy operations, a bluetooth user interface is utilized to determine parameter value and to remote control via a cell phone. In the image recognition system, the images captured using color CCD camera through DT-Acquire Card in the computer are converted into grayscale and binarization, and the noises are eliminated through erosion and dilation. Finally, the actual locations of the target are obtained. The Fuzzy Logic toolbox of Matlab / Simulink is utilized to design a PD fuzzy controller. The PD’s parameters are adjusted according to the position errors and the changing rate of the errors to complete the fixed-point tracking of the quadrotor.