Ergezer, Halit

Ergezer, Halit

Profile URL

https://hdl.handle.net/20.500.12416/8787

Name Variants

Ergezer, H.

Job Title

Doç. Dr.

Email Address

halitergezer@cankaya.edu.tr

Main Affiliation

06.08. Mekatronik Mühendisliği
Mekatronik Mühendisliği
06. Mühendislik Fakültesi
01. Çankaya Üniversitesi

Status

Current Staff

Sustainable Development Goals

13

CLIMATE ACTION

0

Research Products

8

DECENT WORK AND ECONOMIC GROWTH

0

Research Products

3

GOOD HEALTH AND WELL-BEING

2

Research Products

15

LIFE ON LAND

0

Research Products

17

PARTNERSHIPS FOR THE GOALS

0

Research Products

14

LIFE BELOW WATER

0

Research Products

4

QUALITY EDUCATION

0

Research Products

11

SUSTAINABLE CITIES AND COMMUNITIES

1

Research Products

6

CLEAN WATER AND SANITATION

0

Research Products

10

REDUCED INEQUALITIES

0

Research Products

9

INDUSTRY, INNOVATION AND INFRASTRUCTURE

0

Research Products

12

RESPONSIBLE CONSUMPTION AND PRODUCTION

0

Research Products

2

ZERO HUNGER

0

Research Products

1

NO POVERTY

0

Research Products

7

AFFORDABLE AND CLEAN ENERGY

0

Research Products

5

GENDER EQUALITY

0

Research Products

16

PEACE, JUSTICE AND STRONG INSTITUTIONS

0

Research Products

This researcher does not have a Scopus ID.

This researcher does not have a WoS ID.

Scholarly Output

22

Articles

10

Views / Downloads

716/1114

Supervised MSc Theses

3

Supervised PhD Theses

0

WoS Citation Count

27

Scopus Citation Count

42

WoS h-index

3

Scopus h-index

4

Patents

0

Projects

0

WoS Citations per Publication

1.23

Scopus Citations per Publication

1.91

Open Access Source

11

Supervised Theses

3

Google Analytics Visitor Traffic

Journal	Count
Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi	2
IEEE Access	2
29th IEEE Conference on Signal Processing and Communications Applications (SIU) -- JUN 09-11, 2021 -- ELECTR NETWORK	2
Measurement and Control	2
2025 International Conference on Unmanned Aircraft Systems-ICUAS-Annual -- MAY 14-17, 2025 -- Charlotte, NC	1

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Scopus Quartile Distribution

Competency Cloud

Scholarly Output Search Results

Now showing 1 - 10 of 22

Lpi Radar Waveform Classification Using Binary Svm and Multi-Class Svm Based on Principal Components of Tfi
(2020) Ergezer, Halit; Bektas, Almila
Since cognition has become an important topic in Electronic Warfare(EW) systems, Electronic Support Measures (ESM) are used to monitor, interceptand analyze radar signals. Low Probability of Intercept (LPI) radars are preferredto be able to detect targets without being detected by ESM systems. Because of theirproperties as low power, variable frequency, wide bandwidth, LPI Radarwaveforms are difficult to intercept with ESM systems. In addition to intercepting,the determination of the waveform types used by the LPI Radars is also veryimportant for applying counter-measures against these radars. In this study, asolution for the LPI Radar waveform recognition is proposed. The solution is basedon the training of Support Vector Machine (SVM) after applying PrincipalComponent Analysis (PCA) to the data obtained by Time-Frequency Images (TFI).TFIs are generated using Choi-Williams Distribution. High energy regions on theseimages are cropped automatically and then resized to obtain uniform data set. Toobtain the best result in SVM, the SVM Hyper-Parameters are also optimized.Results are obtained by using one-against-all and one-against-one methods. Betterclassification performance than those given in the literature has been obtainedespecially for lower Signal to Noise Ratio (SNR) values. The cross-validated resultsobtained are compared with the best results in the literature.
Citation - WoS: 1
Evaluation of Features Used in Electromyography Classification
(Ieee, 2021) Ergezer, Halit; Alguner, Ayber Eray
Classification of electromyography (EMG) signals using machine learning has been studied for a long time. Today, this classification is tried to be made more accurate, fast and applicable by using the methods developed. However, beside this effort, it is suspected that researchers are using features without taking into account the effects on the classification performance, but often by influence of other researches. From this point of view, the effects of some features used in studies published in recent years on classification performance were tested and the results obtained were shared. In the experiments performed using a common method support vector machine (SVM), it was found that increasing the number of features does not always provide an increase in performance, even in some cases, it causes a decrease in accuracy rates.
Design and Implementation of Visual Simultaneous Localization and Mapping (Vslam) Navigation System
(Ieee, 2021) Ergezer, Halit; Bekcan, Arda
It is very important to guess the location of the redetected objects and loop closures with the visual simultaneous localization and mapping system (VSLAM), one of the biggest problems of a mobile robot. VSLAM makes it possible to eliminate and/or reduce these applications' errors and realize or improve the robot's direction and position correctly by creating a map of the environment. This study aims to achieve an autonomous indoor/outdoor navigation of a ground robot using VSLAM algorithm in an unknown environment using a monocular camera. In this context, the theoretical information was tested in real-world conditions. Performance of localization and loop closing were compared based on the results obtained by experiments
Citation - WoS: 2
Citation - Scopus: 2
Development of Air-To Engagement Analysis Model of Fighter Aircrafts
(Gazi Univ, Fac Engineering Architecture, 2022) Bektas, Almila; Ergezer, Halit; Erdogan, Sinem
In operational analysis studies; it is possible to model and simulate at an engineering level, engagement level, task level and campaign forces level. In this study, modelling and simulation studies are performed in engagement-level allowing the analysis of air-to-ground engagement effectiveness of fighter aircraft according to the operational environment. The operating environment of the combat aircraft, which provides survivability analysis based on low visibility and electronic mixing capabilities, is created. The search radar and tracking radar models for ground-to-air threats have been designed in accordance with the engagement level. The dynamic model of the fighter aircraft and the ground-to-air missile have been modelled using pseudo 5 degree-of-freedom. Modelling has been carried out to allow the use of changes in the Radar Crosssectional Area (RCS), which is one of the most important factors affecting the survivability of the aircraft, with respect to azimuth and elevation angles. The Radio Frequency (RF) jamming capability of the fighter aircraft has also been modelled in accordance with the engagement level. The results of the generic scenarios for the analysis of the effect of these models' parameters on the survivability of fighter aircraft have been presented.
Optimal Fixed-Wing UAV Rendezvous Via LQR-Based Longitudinal Control
(IEEE, 2025) Buyukekiz, Kadir Bulathan; Ergezer, Halit
This paper proposes an optimal control-based rendezvous strategy for fixed-wing Unmanned Aerial Vehicles (UAVs) using a Linear Quadratic Regulator (LQR). The goal is precisely tracking a moving target while maintaining flight stability and avoiding predefined restricted areas. The controller optimally adjusts UAVs flight parameters to minimize trajectory errors and enhance robustness against environmental disturbances. A penalty-based method is integrated to prevent UAVs from entering restricted areas while ensuring smooth trajectory adaptation. The proposed approach has been tested in MATLAB simulations under multiple scenarios, demonstrating its effectiveness in achieving stable and efficient rendezvous maneuvers. The results confirm that LQR-based control and adaptive penalty mechanisms offer a practical solution for fixed-wing UAV operations in constrained environments.
Citation - WoS: 2
Citation - Scopus: 3
Control Structure Design With Constraints for a Slung Load Quadrotor System
(Sage Publications Ltd, 2024) Leblebicioglu, Kemal; Ergezer, Halit
We propose a control structure for a quadrotor carrying a slung load with swing-angle constraints. This quadrotor is supposed to pass through the waypoints at specified speeds. First, a cascaded PID autopilot is designed, which adaptively gives attention to position and speed requirements as a function of their errors. Its parameters are found from an optimization problem solved using the PSO algorithm. Second, this controller's performance is improved by adding the Complementary Controller employing an ANN. 5. Training data for the ANN is created by solving optimal control problems. The ANN is activated when the swing angle constraint is about to be violated. It is trained using optimal control values corresponding to the cases where the swing angle falls in a particular band about the upper swing angle constraint. Simulations are performed in a MATLAB environment. Finally, some of the simulation results are validated on a physical system.
Formation Control of Fixed-Wing Uavs Using Mpc: Effect of Vehicle Speed
(Ieee, 2024) Ozcelik, Ozge Kartal; Ergezer, Halit
As UAV technology has progressed, its applications have expanded across various sectors such as Surveillance, Military, Maintenance, and Delivery. Due to their cost-effectiveness and safety in operations, UAVs have gained rapid popularity in these domains. Scenarios demanding the coordinated flight of multiple UAVs have become prevalent, leading to various formation types and control strategies tailored to specific use cases. Among these control mechanisms, Model Predictive Control (MPC) has found application in UAV formation flight. This study focuses on the development and implementation of MPC for the formation flight of fixed-wing UAVs. Experiments were conducted utilizing a setup involving three UAVs, elucidating the functionality of MPC and examining the impact of variations in the speed parameter on MPC performance.
Citation - WoS: 1
Citation - Scopus: 2
Classification of Low Probability of Intercept Radar Waveforms Using Gabor Wavelets
(Gazi Univ, Fac Engineering Architecture, 2021) Ergezer, Halit
Low Probability of Intercept (LPI Radar) is a class of radar with specific technical characteristics that make it very difficult to intercept with electronic support systems and radar warning receivers. Because of their properties as low power, variable frequency, wide bandwidth, LPI radar waveforms are difficult to intercept by ESM systems. In recent years, studies on the classification of waveforms used by these types of radar have been accelerated. In this study, Time-Frequency Images (TFI) has been obtained from the LPI radars waveforms by using Choi-Williams Distribution method. From these images, feature vectors have been generated using Gabor Wavelet transform. In contrast to many methods in the literature, waveform classification has been performed by directly comparing the feature vectors obtained without using any machine learning method. With the method we propose, classification accuracies were obtained at intervals of 2 dB between -20 dB and 10 dB and performed at reasonable classification accuracy rates up to -8 dB SNR value. Better results than the best reported in the literature were obtained for some signal types. The results obtained for all waveform types are given in comparison with the results of the existing methods in the literature.
Citation - WoS: 5
Citation - Scopus: 6
Multi-Objective Trajectory Planning for Slung-Load Quadrotor System
(Ieee-inst Electrical Electronics Engineers inc, 2021) Ergezer, Halit
In this article, multi-objective trajectory planning has been carried out for a quadrotor carrying a slung load. The goal is to obtain non-dominated solutions for path length, mission duration, and dissipated energy cost functions. These costs are optimized by imposing constraints on the slung-load quadrotor system's endpoints, borders, obstacles, and dynamical equations. The dynamic model of a slung-load quadrotor system is used in the Euler-Lagrange formulation. Although the differential flatness feature is mostly used in this system's trajectory planning, a fully dynamic model has been used in our study. A new multi-objective Genetic Algorithm has been developed to solve path planning, aiming to optimize trajectory length, mission time, and energy consumed during the mission. The solution process has a three-phase algorithm: Phase-1 is about randomly generating waypoints, Phase-2 is about constructing the initial non-dominated pool, and the final phase, Phase-3, is obtaining the solution. In addition to conventional genetic operators, simple genetic operators are proposed to improve the trajectories locally. Pareto Fronts have been obtained corresponding to exciting scenarios. The method has been tested, and results have been presented at the end. A comparison of the solutions obtained with MOGA operators and MOPSO over hypervolume values is also presented.
Çoklu ˙IHA Kullanımı ile Kabloya Asılı Yük Ta¸sınımı Transportation of Cable Suspended Slung Load System Using Multiple UAVs
(2022) Can, Süleyman Emre; Leblebicioğlu, M. Kemal; Ergezer, Halit
Bu çalı¸smada, kablolar ile asılı esnemeyen bir yükün ortakla¸sa ta¸sınımı için kontrolcü tasarımı tanıtılmı¸stır. Yük, birden çok insansız hava aracına (˙IHA) yükün kablo ile baglanması ˘ ile ta¸sınmakta olup, istenen üç boyutlu rota üzerinde hareket etmesi saglanmaktadır. Sistemde yük lider olarak alınmaktadır. ˘ Hiyerar¸sik ve merkezcil bir yapıda kontrol edilmektedir. Ta¸sıma görevi, bir optimizasyon problemi olarak ele alınmı¸stır. Sistemi istenen rotada hareket ettirebilmek için bir otopilot algoritması tasarlanmı¸s olup PD yapıları kullanılarak olu¸sturulmu¸stur. Pozisyon kontrolcüsünün çıktısı kontrol atama matrisi tarafından ele alınmaktadır ve uygun kuvvet dagılımını sistemin istenen ˘ davranı¸slarına uygun olacak ¸sekilde türetmektedir. Kontrolcü performansları, takip edilmesi istenen bir rota üzerinde test edilmektedir.

Ergezer, Halit

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Turkish CoHE Profile ID

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Files

Sustainable Development Goals

13

CLIMATE ACTION

0

Research Products

8

DECENT WORK AND ECONOMIC GROWTH

0

Research Products

3

GOOD HEALTH AND WELL-BEING

2

Research Products

15

LIFE ON LAND

0

Research Products

17

PARTNERSHIPS FOR THE GOALS

0

Research Products

14

LIFE BELOW WATER

0

Research Products

4

QUALITY EDUCATION

0

Research Products

11

SUSTAINABLE CITIES AND COMMUNITIES

1

Research Products

6

CLEAN WATER AND SANITATION

0

Research Products

10

REDUCED INEQUALITIES

0

Research Products

9

INDUSTRY, INNOVATION AND INFRASTRUCTURE

0

Research Products

12

RESPONSIBLE CONSUMPTION AND PRODUCTION

0

Research Products

2

ZERO HUNGER

0

Research Products

1

NO POVERTY

0

Research Products

7

AFFORDABLE AND CLEAN ENERGY

0

Research Products

5

GENDER EQUALITY

0

Research Products

16