Emir Kutluay | Hacettepe University (original) (raw)
Papers by Emir Kutluay
Akıllı ulaşım sistemleri ve uygulamaları dergisi, Oct 22, 2023
The aim of the paper is to propose collision-free path planning algorithm for autonomous parallel... more The aim of the paper is to propose collision-free path planning algorithm for autonomous parallel parking based on Ackermann steering geometry. A geometrical path planning algorithm has been employed for generating a path that is based on two straight lines and two identical circles. The algorithm is taking into account that the left side of the street is taken as another parking slot occupied by full of cars. The ego's kinematics model appropriate for the low-velocity parking scenario and the maximum allowable steering angle for the narrow streets is used in the path planning stage by considering mechanical and environmental limits. According to the steering angle, required length of the parking space is obtained. The algorithm can adapt itself according to the lateral position of the ego in case it is parallel to other parked cars. The steering angle to be used and the required parking space length according to the lateral position of the vehicle in the environmental model are given with graphics.
Fırat Üniversitesi Mühendislik Bilimleri Dergisi
Bu çalışmada muharip bir hava aracının iniş koşusu esnasındaki yanal hareketini belirleyecek güdü... more Bu çalışmada muharip bir hava aracının iniş koşusu esnasındaki yanal hareketini belirleyecek güdüm algoritmaları karşılaştırılmıştır. Muharip hava aracı ve yanal ivmeyi tutan iç döngü otopilot beraber birinci derece bir transfer fonksiyonu şeklinde modellenmiştir. Beş farklı güdüm algoritması teklif edilmiştir. Bu algoritmalar modifiye edilmiş orantılı havuç takip, vektör alanı güdüm, kayan kip güdüm, doğrusal kayan kip güdüm ve geometrik öngörülü güdüm algoritmalarıdır. Karşılaştırmalar yapıldıktan sonra literatürdeki bulgularla paralel olarak çizgi takibi açısından vektör alanı güdüm algoritmasının en başarılı olduğu, kontrol eforu açısından değerlendirildiğinde modifiye edilmiş orantılı havuç takip algoritmasının en başarılı olduğu, doğrusal kayan kip güdüm algoritmasının da bu ikisinin arasında sonuç verdiği görülmüştür. Kalan iki algoritmanın ise performanslarına göre çok fazla kontrol eforu gerektirdikleri için bu uygulama için uygun olmadıkları değerlendirilmiştir.
International Journal of Refrigeration
Vehicle System Dynamics, 2014
ABSTRACT In this work, a literature survey on the validation of vehicle dynamics simulation model... more ABSTRACT In this work, a literature survey on the validation of vehicle dynamics simulation models is presented. Estimating the dynamic responses of existing or proposed vehicles has a wide array of applications in the development of vehicle technologies, e.g. active suspensions, controller design, driver assistance systems, etc. Although simulation environments, measurement tools and mathematical theories on vehicle dynamics are well established, the methodical link between the experimental test data and validity analysis of the simulation model is still lacking. This report presents different views on the definition of validation, and its usage in vehicle dynamics simulation models.
The simulation of vehicle dynamics has a wide array of applications in the development of vehicle... more The simulation of vehicle dynamics has a wide array of applications in the development of vehicle technologies. This study deals with the methodological aspect of the problem of assessing the validity of a simulation using double lane change maneuver as the experimental data source. The maneuver time history is analyzed. Problems in handling the obtained measurements and possibilities to assess the maneuver are examined. Techniques to split and align the data are presented and compared. Methodologies to handle the experimental and simulation data are introduced. The presented methods can be utilized in order to achieve more time and cost efficient simulation projects with increased model confidence. 1
A terminal sliding-mode guidance law is proposed in order to achieve actuator fault tolerance and... more A terminal sliding-mode guidance law is proposed in order to achieve actuator fault tolerance and desired terminal impact angle for an anti-tank missile. Impact angle is an important property for anti-tank missiles; however, this property is not considered together with fault tolerance in the literature. In order to increase robustness of the guidance, target acceleration is covered in guidance law design. During the design process of the guidance law, a sliding surface is determined from the engagement dynamics. Reaching law is designed by considering finite-time convergence and disturbance rejection. After completing the design process, simulations are performed to test guidance law’s performance. INTRODUCTION Considering missile’s objective of intercepting the target accurately, comprehensive design of guidance law is significant. On the flight, missiles are exposed of various disturbances and uncertainties. These terms are generally unmeasurable and they affect the interception ...
Bu calismada gunumuz tasitlarinda kullanilan serit takip sistemleri icin yenilikci bir mudahale k... more Bu calismada gunumuz tasitlarinda kullanilan serit takip sistemleri icin yenilikci bir mudahale konfigurasyonu tasarlanmistir. Direksiyon acisi ile koordineli bir sekilde tasitin arka tekerleklerine uygulanan frenleme torku ile uc tekerlegin kuvvet potansiyelinden faydalanilmasi ve boylece tasitin yanal kontrolunde sistem performansinin artirilmasi amaclanmistir. Kontrolde frenleme torku fren basinc degisimi ile surus durumuna gore secilen herhangi bir tekerlekte degistirilmekte ve bu sayede yanal kontrol saglanabilmektedir. Bunun icin tek izli tasit modeli kullanilarak bir Lineer ikinci dereceden Regulator ( Linear-Quadratic Regulator, LQR) kontrolcusu tasarlanmistir. Daha sonra Simulink ve CarMaker programlari kullanilarak simulasyonlar yapilmistir. Sistemin performansini gozlemleyebilmek icin savrulma acisi degisim hizi, savrulma acisi ve yanal mesafe degiskenleri icin, sirasiyla viraj yaricapi, aci ve yanal mesafe degerleri kontrol girdisi olarak kullanilmakta ve testler bu dege...
In this study a step by step methodology for frequency domain validation of vehicle dynamics simu... more In this study a step by step methodology for frequency domain validation of vehicle dynamics simulation models is presented. Vehicle dynamics models are used to predict the dynamic properties of proposed or existing vehicles and have an important role in development of many automotive technologies. The effectiveness of vehicle dynamics simulations can be improved, if the simulation and the modeling process are optimized and standardized. To this aim a data handling methodology based on V-Model framework is presented and the steps of this process concerning frequency domain validation are explained. The process is demonstrated using data obtained by performing the sine- sweep maneuver with a test vehicle. The results of the analysis are presented and the properties of the validation methodology are discussed. The proposed methodology aims to achieve time and cost efficient simulation projects with increased model reliability by enhancing the traceability of the validation process.
.................................................................................................... more ......................................................................................................................... VII 1 Introduction .................................................................................................................. 1 1.1 Motivation and Goals ............................................................................................. 1 1.2 Structure of the Thesis ............................................................................................ 2 2 State of the Art .............................................................................................................. 3 2.1 Verification and Validation of Computational Models ........................................... 3 2.1.1 Definitions of Concepts of Verification and Validation .......................... 4 2.1.2 Philosophical Aspect .............................................................................. 6 2.1.3 Approaches to Verification and Validation ............................................. 8 2.2 Validation and Vehicle Dynamics Simulation Models ......................................... 14 2.2.1 Vehicle Dynamics and Modeling .......................................................... 14 2.2.2 Practice of Validation of Simulation Models for Vehicle Dynamics .... 17 2.2.3 Theory of Validation of Simulation Models for Vehicle Dynamics ..... 21 2.2.4 Expert Views on the Subject ................................................................. 25 2.3 Conclusion ............................................................................................................ 26 3 Proposed Validation Paradigm ................................................................................. 28 3.1 Analysis of Real World Maneuvers ...................................................................... 28 3.2 Classification of Test Maneuvers.......................................................................... 31 3.3 The V-Model ......................................................................................................... 36 3.4 General Validation Methodology According to V-Model ..................................... 38 3.5 Conclusion ............................................................................................................ 40 4 Case Studies ................................................................................................................ 42 4.1 Methodology ......................................................................................................... 42 4.2 Tools and Research Environment ......................................................................... 43 4.2.1 Test Vehicle and Test Track .................................................................. 43 4.2.2 Simulation Model ................................................................................. 46
In this work, a method for obtaining a set of optimized maximum wheel steering angles for a multi... more In this work, a method for obtaining a set of optimized maximum wheel steering angles for a multiaxle vehicle with multiaxle steering is proposed. During low-speed operations, multiaxle vehicles must have a specified minimum turning radius to traverse crowded areas. The conventional geometrically correct steering configuration may not result in the desired turning radius due to constraints on the maximum steering angles. In such cases, large tire lateral slip angles may be introduced to decrease the turning radius. However, high tire lateral slip angles cause high tire wear. The proposed optimization process aims to achieve the minimum possible turning radius together with minimum tire lateral slip angles. Genetic algorithm is used in the optimization. A case study is conducted with an 8×8 all-wheel steering off-road vehicle. Results show that significant reductions in turning radius and lateral tire slip angles can be achieved.
La presente invention concerne un systeme permettant de garder et de suivre sa voie de circulatio... more La presente invention concerne un systeme permettant de garder et de suivre sa voie de circulation (1), qui amene un vehicule possedant un systeme ESC a freiner de telle sorte qu'il soit dirige dans la voie de circulation lors de la detection qu'il s'approche de la ligne de voie de circulation. Le systeme selon l'invention pour garder et suivre sa voie de circulation (1) qui est utilise dans des vehicules possedant un systeme ESC (A) et monte sur le vehicule par la suite comprend : au moins une unite de detection (2) qui calcule les voies de circulation sur la route et egalement la position du vehicule a l'interieur de ces voies de circulation; au moins une unite de decision (3) qui evalue la possibilite que le vehicule sorte de la voie de circulation a la lumiere des informations recues en provenance de l'unite de capteur (2) et decide s'il existe un danger ou non; au moins une unite de detection de danger (4) qui decide de quelle maniere l'intervent...
Vehicle System Dynamics
In this work, a literature survey on the validation of vehicle dynamics simulation models is pres... more In this work, a literature survey on the validation of vehicle dynamics simulation models is presented. Estimating the dynamic responses of existing or proposed vehicles has a wide array of applications in the development of vehicle technologies, e.g. active suspensions, controller design, driver assistance systems, etc. Although simulation environments, measurement tools and mathematical theories on vehicle dynamics are well established, the methodical link between the experimental test data and validity analysis of the simulation model is still lacking. This report presents different views on the definition of validation, and its usage in vehicle dynamics simulation models.
IEEE Proceedings of the 2012 Winter Simulation Conference (WSC)
The simulation of vehicle dynamics has a wide array of applications in the development of vehicle... more The simulation of vehicle dynamics has a wide array of applications in the development of vehicle technologies. This study deals with the methodological aspect of the problem of assessing the validity of a simulation using double lane change maneuver as the experimental data source. The maneuver time history is analyzed. Problems in handling the obtained measurements and possibilities to assess the maneuver are examined. Techniques to split and align the data are presented and compared. Methodologies to handle the experimental and simulation data are introduced. The presented methods can be utilized in order to achieve more time and cost efficient simulation projects with increased model confidence.
Akıllı ulaşım sistemleri ve uygulamaları dergisi, Oct 22, 2023
The aim of the paper is to propose collision-free path planning algorithm for autonomous parallel... more The aim of the paper is to propose collision-free path planning algorithm for autonomous parallel parking based on Ackermann steering geometry. A geometrical path planning algorithm has been employed for generating a path that is based on two straight lines and two identical circles. The algorithm is taking into account that the left side of the street is taken as another parking slot occupied by full of cars. The ego's kinematics model appropriate for the low-velocity parking scenario and the maximum allowable steering angle for the narrow streets is used in the path planning stage by considering mechanical and environmental limits. According to the steering angle, required length of the parking space is obtained. The algorithm can adapt itself according to the lateral position of the ego in case it is parallel to other parked cars. The steering angle to be used and the required parking space length according to the lateral position of the vehicle in the environmental model are given with graphics.
Fırat Üniversitesi Mühendislik Bilimleri Dergisi
Bu çalışmada muharip bir hava aracının iniş koşusu esnasındaki yanal hareketini belirleyecek güdü... more Bu çalışmada muharip bir hava aracının iniş koşusu esnasındaki yanal hareketini belirleyecek güdüm algoritmaları karşılaştırılmıştır. Muharip hava aracı ve yanal ivmeyi tutan iç döngü otopilot beraber birinci derece bir transfer fonksiyonu şeklinde modellenmiştir. Beş farklı güdüm algoritması teklif edilmiştir. Bu algoritmalar modifiye edilmiş orantılı havuç takip, vektör alanı güdüm, kayan kip güdüm, doğrusal kayan kip güdüm ve geometrik öngörülü güdüm algoritmalarıdır. Karşılaştırmalar yapıldıktan sonra literatürdeki bulgularla paralel olarak çizgi takibi açısından vektör alanı güdüm algoritmasının en başarılı olduğu, kontrol eforu açısından değerlendirildiğinde modifiye edilmiş orantılı havuç takip algoritmasının en başarılı olduğu, doğrusal kayan kip güdüm algoritmasının da bu ikisinin arasında sonuç verdiği görülmüştür. Kalan iki algoritmanın ise performanslarına göre çok fazla kontrol eforu gerektirdikleri için bu uygulama için uygun olmadıkları değerlendirilmiştir.
International Journal of Refrigeration
Vehicle System Dynamics, 2014
ABSTRACT In this work, a literature survey on the validation of vehicle dynamics simulation model... more ABSTRACT In this work, a literature survey on the validation of vehicle dynamics simulation models is presented. Estimating the dynamic responses of existing or proposed vehicles has a wide array of applications in the development of vehicle technologies, e.g. active suspensions, controller design, driver assistance systems, etc. Although simulation environments, measurement tools and mathematical theories on vehicle dynamics are well established, the methodical link between the experimental test data and validity analysis of the simulation model is still lacking. This report presents different views on the definition of validation, and its usage in vehicle dynamics simulation models.
The simulation of vehicle dynamics has a wide array of applications in the development of vehicle... more The simulation of vehicle dynamics has a wide array of applications in the development of vehicle technologies. This study deals with the methodological aspect of the problem of assessing the validity of a simulation using double lane change maneuver as the experimental data source. The maneuver time history is analyzed. Problems in handling the obtained measurements and possibilities to assess the maneuver are examined. Techniques to split and align the data are presented and compared. Methodologies to handle the experimental and simulation data are introduced. The presented methods can be utilized in order to achieve more time and cost efficient simulation projects with increased model confidence. 1
A terminal sliding-mode guidance law is proposed in order to achieve actuator fault tolerance and... more A terminal sliding-mode guidance law is proposed in order to achieve actuator fault tolerance and desired terminal impact angle for an anti-tank missile. Impact angle is an important property for anti-tank missiles; however, this property is not considered together with fault tolerance in the literature. In order to increase robustness of the guidance, target acceleration is covered in guidance law design. During the design process of the guidance law, a sliding surface is determined from the engagement dynamics. Reaching law is designed by considering finite-time convergence and disturbance rejection. After completing the design process, simulations are performed to test guidance law’s performance. INTRODUCTION Considering missile’s objective of intercepting the target accurately, comprehensive design of guidance law is significant. On the flight, missiles are exposed of various disturbances and uncertainties. These terms are generally unmeasurable and they affect the interception ...
Bu calismada gunumuz tasitlarinda kullanilan serit takip sistemleri icin yenilikci bir mudahale k... more Bu calismada gunumuz tasitlarinda kullanilan serit takip sistemleri icin yenilikci bir mudahale konfigurasyonu tasarlanmistir. Direksiyon acisi ile koordineli bir sekilde tasitin arka tekerleklerine uygulanan frenleme torku ile uc tekerlegin kuvvet potansiyelinden faydalanilmasi ve boylece tasitin yanal kontrolunde sistem performansinin artirilmasi amaclanmistir. Kontrolde frenleme torku fren basinc degisimi ile surus durumuna gore secilen herhangi bir tekerlekte degistirilmekte ve bu sayede yanal kontrol saglanabilmektedir. Bunun icin tek izli tasit modeli kullanilarak bir Lineer ikinci dereceden Regulator ( Linear-Quadratic Regulator, LQR) kontrolcusu tasarlanmistir. Daha sonra Simulink ve CarMaker programlari kullanilarak simulasyonlar yapilmistir. Sistemin performansini gozlemleyebilmek icin savrulma acisi degisim hizi, savrulma acisi ve yanal mesafe degiskenleri icin, sirasiyla viraj yaricapi, aci ve yanal mesafe degerleri kontrol girdisi olarak kullanilmakta ve testler bu dege...
In this study a step by step methodology for frequency domain validation of vehicle dynamics simu... more In this study a step by step methodology for frequency domain validation of vehicle dynamics simulation models is presented. Vehicle dynamics models are used to predict the dynamic properties of proposed or existing vehicles and have an important role in development of many automotive technologies. The effectiveness of vehicle dynamics simulations can be improved, if the simulation and the modeling process are optimized and standardized. To this aim a data handling methodology based on V-Model framework is presented and the steps of this process concerning frequency domain validation are explained. The process is demonstrated using data obtained by performing the sine- sweep maneuver with a test vehicle. The results of the analysis are presented and the properties of the validation methodology are discussed. The proposed methodology aims to achieve time and cost efficient simulation projects with increased model reliability by enhancing the traceability of the validation process.
.................................................................................................... more ......................................................................................................................... VII 1 Introduction .................................................................................................................. 1 1.1 Motivation and Goals ............................................................................................. 1 1.2 Structure of the Thesis ............................................................................................ 2 2 State of the Art .............................................................................................................. 3 2.1 Verification and Validation of Computational Models ........................................... 3 2.1.1 Definitions of Concepts of Verification and Validation .......................... 4 2.1.2 Philosophical Aspect .............................................................................. 6 2.1.3 Approaches to Verification and Validation ............................................. 8 2.2 Validation and Vehicle Dynamics Simulation Models ......................................... 14 2.2.1 Vehicle Dynamics and Modeling .......................................................... 14 2.2.2 Practice of Validation of Simulation Models for Vehicle Dynamics .... 17 2.2.3 Theory of Validation of Simulation Models for Vehicle Dynamics ..... 21 2.2.4 Expert Views on the Subject ................................................................. 25 2.3 Conclusion ............................................................................................................ 26 3 Proposed Validation Paradigm ................................................................................. 28 3.1 Analysis of Real World Maneuvers ...................................................................... 28 3.2 Classification of Test Maneuvers.......................................................................... 31 3.3 The V-Model ......................................................................................................... 36 3.4 General Validation Methodology According to V-Model ..................................... 38 3.5 Conclusion ............................................................................................................ 40 4 Case Studies ................................................................................................................ 42 4.1 Methodology ......................................................................................................... 42 4.2 Tools and Research Environment ......................................................................... 43 4.2.1 Test Vehicle and Test Track .................................................................. 43 4.2.2 Simulation Model ................................................................................. 46
In this work, a method for obtaining a set of optimized maximum wheel steering angles for a multi... more In this work, a method for obtaining a set of optimized maximum wheel steering angles for a multiaxle vehicle with multiaxle steering is proposed. During low-speed operations, multiaxle vehicles must have a specified minimum turning radius to traverse crowded areas. The conventional geometrically correct steering configuration may not result in the desired turning radius due to constraints on the maximum steering angles. In such cases, large tire lateral slip angles may be introduced to decrease the turning radius. However, high tire lateral slip angles cause high tire wear. The proposed optimization process aims to achieve the minimum possible turning radius together with minimum tire lateral slip angles. Genetic algorithm is used in the optimization. A case study is conducted with an 8×8 all-wheel steering off-road vehicle. Results show that significant reductions in turning radius and lateral tire slip angles can be achieved.
La presente invention concerne un systeme permettant de garder et de suivre sa voie de circulatio... more La presente invention concerne un systeme permettant de garder et de suivre sa voie de circulation (1), qui amene un vehicule possedant un systeme ESC a freiner de telle sorte qu'il soit dirige dans la voie de circulation lors de la detection qu'il s'approche de la ligne de voie de circulation. Le systeme selon l'invention pour garder et suivre sa voie de circulation (1) qui est utilise dans des vehicules possedant un systeme ESC (A) et monte sur le vehicule par la suite comprend : au moins une unite de detection (2) qui calcule les voies de circulation sur la route et egalement la position du vehicule a l'interieur de ces voies de circulation; au moins une unite de decision (3) qui evalue la possibilite que le vehicule sorte de la voie de circulation a la lumiere des informations recues en provenance de l'unite de capteur (2) et decide s'il existe un danger ou non; au moins une unite de detection de danger (4) qui decide de quelle maniere l'intervent...
Vehicle System Dynamics
In this work, a literature survey on the validation of vehicle dynamics simulation models is pres... more In this work, a literature survey on the validation of vehicle dynamics simulation models is presented. Estimating the dynamic responses of existing or proposed vehicles has a wide array of applications in the development of vehicle technologies, e.g. active suspensions, controller design, driver assistance systems, etc. Although simulation environments, measurement tools and mathematical theories on vehicle dynamics are well established, the methodical link between the experimental test data and validity analysis of the simulation model is still lacking. This report presents different views on the definition of validation, and its usage in vehicle dynamics simulation models.
IEEE Proceedings of the 2012 Winter Simulation Conference (WSC)
The simulation of vehicle dynamics has a wide array of applications in the development of vehicle... more The simulation of vehicle dynamics has a wide array of applications in the development of vehicle technologies. This study deals with the methodological aspect of the problem of assessing the validity of a simulation using double lane change maneuver as the experimental data source. The maneuver time history is analyzed. Problems in handling the obtained measurements and possibilities to assess the maneuver are examined. Techniques to split and align the data are presented and compared. Methodologies to handle the experimental and simulation data are introduced. The presented methods can be utilized in order to achieve more time and cost efficient simulation projects with increased model confidence.