Optimal Tracking System Research Articles

Modulating Retroreflector Based Free Space Optical Link for UAV-to-Ground Communications

Weight reduction and low power consumption are key requirements in the next generation of unmanned aerial vehicle (UAV) networks. Employing modulating retro-reflector (MRR)-based free space optical (FSO) technology is an innovative technique for UAV-to-ground communication in order to reduce the payload weight and power consumption of UAVs which leads to increased maneuverability and flight time of UAV. In this paper, we consider an MRR-based FSO system for UAV-to-ground communication. We will show that the performance of the considered system is very sensitive to tracking errors. Therefore, to assess the benefits of MRR-based UAV deployment for FSO communications, the MRR-based UAV FSO channel is characterized by taking into account tracking system errors along with UAV’s orientation fluctuations, link length, UAV’s height, optical beam divergence angle, effective area of MRR, atmospheric turbulence and optical channel loss in the double-pass channels. To enable effective performance analysis, tractable and closed-form expressions are derived for probability density function of end-to-end signal to noise ratio, outage probability and bit error rate of the considered system under both weak-to-moderate and moderate-to-strong atmospheric turbulence conditions. The accuracy of the analytical expressions is verified by extensive simulations. Analytical results are then used to study the relationship between the optimal system design and tracking system errors.

Real time Paralysis Patient Health MonitoringSystem using Wireless Communication

A survey of the Global Burden of Diseases (GBD) estimated that, approximately 5.8 million peoplelose their lives due to stroke. Stroke is the major cause of paralysis, which affects almost 33.7% of the population with paralysis. But there is no optimal tracking system to monitor the patient’s healthand daily needs. In this high-speed world, it is not possible to constantly take care of their near oneswho need their help. To overcome such difficulties paralyzed patient monitoring equipment is introduced. During the survey we come across many hospitals and NGOs serving paralytic patientswith their whole or partial body disabled by the Paralysis attack. Those people in most cases are notable to convey their needs as they can’t be able to speak properly nor can they convey through signlanguage due to loss in motion control in their brain. In this way the Automated Paralysis Patient Care System truly automates the care taking ability of the patient which ensures a timely attention to the patient and thus for a good health of the patient.

A Novel Wavelet-based Optimal Linear Quadratic Tracker for Time-varying Systems with Multiple Delays

A novel method for solving optimal tracking control of linear quadratic time-varying systems with differentforms of time delays in state and input variables and with constraints is presented in this paper. Using the concepts of two powerful wavelets, Legendre and Chebyshev wavelets, we convert the optimal tracking problem to a static optimization one. The method is presented in a general from by which one can utilize it by other wavelets. The proposed method has the ability to solve the problems with systems of integer and fractional orders. After determining open-loop solutions of time-delay tracking systems, closed-loop suboptimal controller is designed. A highly successful wavelet-based suboptimal controller is introduced in this work. This alternative method is applied on some optimal tracking systems.

Energy-Efficient Path-Following Control System of Automated Guided Vehicles

The theoretical bases of optimal tracking systems synthesis are considered. The main purpose of such systems is to keep the error between the actual and desired outputs of the system at a low level with minimal energy consumption. This concept is appealing to the fact that the vast majority of control systems solve problems without regard to the expediency of using the internal energy resources of the system itself. The main task of an automated guided vehicle is to move from one point to another. An algorithm for forming the desired trajectory between two points, specified on the map, was developed. With optimal energy consumption, this approach will make a practical contribution to the field of automation, self-driving cars, etc. The concept of optimal, energy-efficient control has been implemented. Several experiments with different regulators have been carried out to verify the concept of the tracking systems and to convince the significant advantage of the optimality among the other systems.

Hybrid Tracker Based Optimal Path Tracking System of Autonomous Driving for Complex Road Environments

Path tracking system plays a key technology in autonomous driving. The system should be driven accurately along the lane and be careful not to cause any inconvenience to passengers. To address such tasks, this research proposes hybrid tracker based optimal path tracking system. By applying a deep learning based lane detection algorithm and a designated fast lane fitting algorithm, this research developed a lane processing algorithm that shows a match rate with actual lanes with minimal computational cost. In addition, three modified path tracking algorithms were designed using the GPS based path or the vision based path. In the driving system, a match rate for the correct ideal path does not necessarily represent driving stability. This research proposes hybrid tracker based optimal path tracking system by applying the concept of an observer that selects the optimal tracker appropriately in complex road environments. The driving stability has been studied in complex road environments such as straight road with multiple 3-way junctions, roundabouts, intersections, and tunnels. Consequently, the proposed system experimentally showed the high performance with consistent driving comfort by maintaining the vehicle within the lanes accurately even in the presence of high complexity of road conditions. Code will be available in https://github.com/DGIST-ARTIV .

Optimal Estimation and Tracking Control for Variable-speed Wind Turbine with PMSG

Designing an optimal tracking controller and system observer is a nonlinear problem in the variable-speed wind energy conversion system (WECS). In this paper, an adjusted feedforward and feedback optimal controller with extended Kalman filter (EKF) is introduced to estimate and control the permanent magnet synchronous generator (PMSG) for the maximum power point tracking (MPPT) with several disturbances of the wind speed. An augmented model of wind turbine and PMSG is expanded, and then the parameters of the optimal controller and estimator are obtained. The dynamic stability of the closed-loop system with feedback-feedforward controller (FFC), EKF and speed controller are analyzed. To compare the dynamic performance of EKF and FFC with the conventional controllers, numerical results are demonstrated with the disturbances of the wind speed and faults in power grid.

Optimal Discriminator and Limiting Accuracy of Height Measurement for a Spaceborne Oceanographic Radar Altimeter

The required accuracy performance of a high-precision oceanographic radar altimeter can be achieved by designing a height-tracking system. The optimal discriminator of the tracking system is synthesized in this letter, and the calculation methods for its discriminating characteristics and measurement error performance are investigated. The structure of the optimized tracking system is outlined. Using the obtained results, the dependence of the limiting accuracy of a single delay-time measurement on the signal-to-noise ratio is determined. The limiting accuracy obtained by the discriminator can be specified as the measurement performance of the altimeter system.

Dynamic Friction Characterization of a Linear Servo Motor Using an Optimal Sinusoidal Reference Tracking Controller

This letter presents the design of an optimal sinusoidal tracking and disturbance rejection controller for a linear voice-coil motor. The optimal tracking and disturbance rejection system is used to characterize the nonlinear dynamic friction of the servo motor. The control scheme allows investigating the hysteresis characteristics of friction as a function of frequency. Experimental results indicate the effectiveness of the proposed identification procedure for the dynamic friction estimation.

VR System development for nuclear power plant in Korea

By using Virtual Reality(VR) technology which is one of the core technologies 4th industry revolution, we are developing VR System development for Nuclear power plants from April 2018 to March 2021. This Research and Development (R&D) project includes VR based “Walk-down System development”, “optimal path tracking system development”, “major equipment transfer and installation simulation”, etc. When fully developed, These R&D results will be applied the construction of the Shin-Kori unit 5,6 nuclear power plant construction to check design interference, to establish work planning, and to effectively collect construction experience knowledges to improve our future construction projects in the future. This paper will introduce major technological developments contents of this R&D project. It is expected that the results of this study will contribute dramatically to enhance the efficiency of nuclear power plant design process and the method of construction by simulating installation method of major equipment such as reactor, steam generators and turbine before installing them in the Shin-Kori unit 5,6.

VR System development for nuclear power plant in Korea

By using Virtual Reality(VR) technology which is one of the core technologies 4th industry revolution, we are developing VR System development for Nuclear power plants from April 2018 to March 2021. This Research and Development (R&D) project includes VR based “Walk-down System development”, “optimal path tracking system development”, “major equipment transfer and installation simulation”, etc. When fully developed, These R&D results will be applied the construction of the Shin-Kori unit 5,6 nuclear power plant construction to check design interference, to establish work planning, and to effectively collect construction experience knowledges to improve our future construction projects in the future. This paper will introduce major technological developments contents of this R&D project. It is expected that the results of this study will contribute dramatically to enhance the efficiency of nuclear power plant design process and the method of construction by simulating installation method of major equipment such as reactor, steam generators and turbine before installing them in the Shin-Kori unit 5,6.

Synthesis of Processing Algorithm for Signals with Different Powers in Local Radio Navigation Systems

The paper is aimed at synthesizing and analyzing an optimal algorithm for co-tracking delays and phases of pseudolite signals of different power in local navigation systems using a theory of optimal parameter estimation for several signals received by a navigation receiver in the additive mixture of the receiver internal noise. The analysis of the synthesized tracking algorithm is based on the simulation modeling of a navigation receiver taking account of nonlinear processing in discriminators. New equations describing an optimal complex tracking system that compensate the interfering signals in the processing paths of several incoming signals have been obtained. It has been shown that the use of this system ensures a reliable reception of navigational signals of significantly different power, which is relevant for local navigation systems based on pseudolites. The obtained tracking algorithms can be used in navigation equipment of local pseudolite-based navigation systems and satellite radio navigation systems GLONASS, GPS, Galileo, etc., working with the support of local navigation systems, robust principal component analysis (RPCA), total variation (TV), discriminating internal layers from radio echo sounding data of ice sheets, conjugate gradient method.

Synthesis of Optimal Incoherent Subcarrier Tracking of BOC(1,1) Navigation Signals

Navigation receivers of global positioning systems that are operated in complex electromagnetic environment must have an increased noise immunity characteristic. One way of such noise immunity rising is to use incoherent operating mode of navigation receiver. There are known processing algorithms for navigation signals with Binary Phase Shift Keying (BPSK) modulation. But in the near-term outlook Global Navigation Satellite Systems (GLONASS), Global Positioning Systems (GPS) and Galileo known navigation signals with Binary Offset Carrier (BOC) modulation will be radiated. Processing algorithms for such signals are not described in scientific literature. So it is interesting to work out processing algorithms for BOC modulated signals in incoherent operating mode of navigation receiver. The article is devoted to synthesis and analysis of incoherent subcarrier tracking system under receiving BOC (1,1) navigation signals. To synthesize an optimal tracking system, optimal estimation theory and dual estimation method are used that allow taking into account multi-peak a posteriori distribution of delay that caused by the periodic process (digital sinusoid) in the radio signal modulation function. When analyzing the synthesized estimation algorithm, the procedure for describing delay discriminators and dual variable discriminators were used in the form of a statistical equivalent, including discrimination and fluctuation characteristics. New equations have been obtained that describe optimal tracking system for incoherent mode of a navigation receiver. New expressions for delay and dual variable discriminators are derived. The article gives a scheme for these discriminators and formulas for their statistical characteristics. Simulated results are provided that illustrate accuracy characteristics enhancement. The obtained tracking algorithms may be used in the navigation consumer equipment of GLONASS, GPS, Galileo and other radio-navigation satellite systems operating with BOC(1.1) modulated signals.

Empirical Study on Designing of Gaze Tracking Camera Based on the Information of User's Head Movement.

Gaze tracking is the technology that identifies a region in space that a user is looking at. Most previous non-wearable gaze tracking systems use a near-infrared (NIR) light camera with an NIR illuminator. Based on the kind of camera lens used, the viewing angle and depth-of-field (DOF) of a gaze tracking camera can be different, which affects the performance of the gaze tracking system. Nevertheless, to our best knowledge, most previous researches implemented gaze tracking cameras without ground truth information for determining the optimal viewing angle and DOF of the camera lens. Eye-tracker manufacturers might also use ground truth information, but they do not provide this in public. Therefore, researchers and developers of gaze tracking systems cannot refer to such information for implementing gaze tracking system. We address this problem providing an empirical study in which we design an optimal gaze tracking camera based on experimental measurements of the amount and velocity of user’s head movements. Based on our results and analyses, researchers and developers might be able to more easily implement an optimal gaze tracking system. Experimental results show that our gaze tracking system shows high performance in terms of accuracy, user convenience and interest.

Delay Tracking Algorithm for the Pilot Component of GLONASS Perspective Signal with Code Division Multiple Access

The paper studies the issue of the synthesis of the optimal code delay tracking algorithm for the pilot component of GLONASS perspective signal with BOC(1,1) modulation and processing at subcarrier frequencies. The study objective is synthesis and analysis of optimal code delay tracking algorithm of BOC(1,1) modulated signal (pilot component of L1OC GLONASS perspective signal) using the method of additional variable and processing at subcarrier frequencies. Equations describing optimal tracking system with account to multimodality of code delay aposteriori probability density are calculated using the theory of optimal filtering and the method of additional variable. The structural scheme of delay discriminator with processing at subcarrier frequencies is developed. Discrimination and fluctuation characteristics of synthesized delay discriminator are calculated. The results of the proposed tracking algorithm modelling, which demonstrate its performance and accuracy characteristics, are presented.

The Study of DC Motor Position Controller Parameter Setting and Simulation

Classic setting method not only process trival, but also can't ensure that the controller you get is optimal. In order to obtain satisfactory system performance, in this paper, In this paper, the genetic algorithm is introduced to the dc motor optimal position tracking system control problem. By using it to global optimization of the controller parameters, and setting the current, speed and position controller parameters. The simulation results: PID controller designed by using genetic algorithm can make the response of control system tracking faster and no overshoot,make sure that the system control effect based on the stability and improve the system performance and achieve the actual process requirements. The simulation results verify that the proposed method is effectiveness.

A flexible GPS tracking system for studying bird behaviour at multiple scales

Tracking devices and bio-loggers provide cru- cial information on the ecology and behaviour of birds in their natural environment. An optimal tracking system should be lightweight, measure three-dimensional loca- tions, enable flexible measurement schemes, transmit data remotely and measure environmental variables and bio- logical parameters of the individual. Giving full consider- ation to the traits of birds and the constraints of technology, we have developed a GPS tracking system that attempts to achieve most of the aspirations of an optimal tracking system for free ranging birds without the need to recapture them. Here, we describe the design, performance and limitations of the system. We also present measurements on the tracked Lesser Black-backed Gull Larus fuscus to show how such a system can generate new opportunities for research at multiple scales. The GPS tracker weighs 12 g and includes a GPS receiver, micro-processor, 4 MB of memory for data storage, solar panel and battery. It has a tri-axial accelerometer to monitor behaviour. To maximize flexibility, it is equipped with a radio transceiver for bi- directional communication with a ground-based antenna network, which enables data to be downloaded and new measurement schemes to be uploaded remotely. The sys- tem facilitates a multi-scale approach to studying bird movement, from fine-scale movements (3-s measurement intervals) to long-distance migratory movements (intervals of 20-30 min) of the same individual. We anticipate that flexible tracking systems that enable researchers to opti- mize their measurement protocols will contribute to revo- lutionizing research on animal behaviour and ecology in the next decade.

Active vibration control using optimal LQ tracking system with additional dynamics

This paper focuses on the vibration suppression task using an appropriate controller design for active control of structures with distributed piezoelectric actuators and sensors. The problem arises from the need to control undesired vibrations caused by disturbances or excitations acting upon a structure in an efficient and at the same time a simple way. A special class of disturbances/excitations (periodical, with frequencies equal or near to the eigenfrequencies of the controlled structure) may cause undesired resonant states. In order to reject such disturbances and suppress vibrations in the presence of excitations an optimal LQ controller based on tracking systems with additional dynamics is proposed for the vibration control problem. The controller was tested in the presence of excitations with different frequencies. Controller design is model-based, where for the numeric modelling of the structure the finite element approach was used. Besides, subspace-based model identification was used as well. Controller design, testing and implementation were performed on the funnel-shaped shell structure, the inlet part of the magnetic resonance tomograph. Simulation results as well as the real-time implementation of the controller as a part of the Hardware-in-the-Loop system show considerable vibration suppression in the presence of excitations and confirm the efficiency of the controller.

Design of optimal sampled-data tracking systems with preview

The problem of optimal sampled-data (SD) tracking system design is considered for the case when the reference signal is known in advance over an interval r. A rigorous frequency-domain solution is given on basis of the Laplace transform in continuous time. Formulas determining the order of the optimal controller have been obtained. Limiting properties of the optimal systems as τ → ∞ have been investigated.

Design of Optimal 2-DOF Sampled-Data Systems

A method is presented for synthesis of optimal sampled-data tracking systems with two controllers, one of which is incorporated into the closed loop, while another is placed in feedforward chain. The approach is based on Laplace transform in continuous time and polynomial equations theory. The set of all admissible reference controllers is constructed. The cost function include integral quadratic output and control errors in continuous time.

Polynomial Design of Optimal Sampled-Data Tracking Systems I. Quadratic Optimization

A method of optimal design of digital tracking systems for continuous-time plants is presented. The method is based on the use of Laplace transformation in continuous time and polynomial equation theory. The cost function employed for quadratic optimization takes system performance in continuous time into account. The structure of optimal digital controller transfer function is investigated and its order is determined explicitly. The possibility of designing optimal tracking system for a neutral plant is analyzed.