ROBUST YAW STABILITY CONTROL FOR ELECTRIC VEHICLES BASED ON ACTIVE FRONT STEERING CONTROL THROUGH A STEER-BY-WIRE SYSTEM

남강현,S. OH,H. FUJIMOTO,Y. HORI 한국자동차공학회 2012 International journal of automotive technology Vol.13 No.7

A robust yaw stability control design based on active front steering control is proposed for in-wheel-motored electric vehicles with a Steer-by-Wire (SbW) system. The proposed control system consists of an inner-loop controller (referred to in this paper as the steering angle-disturbance observer (SA-DOB), which rejects an input steering disturbance by feeding a compensation steering angle) and an outer-loop tracking controller (i.e., a PI-type tracking controller) to achieve control performance and stability. Because the model uncertainties, which include unmodeled high frequency dynamics and parameter variations, occur in a wide range of driving situations, a robust control design method is applied to the control system to simultaneously guarantee robust stability and robust performance of the control system. The proposed control algorithm was implemented in a CaSim model, which was designed to describe actual in-wheel-motored electric vehicles. The control performances of the proposed yaw stability control system are verified through computer simulations and experimental results using an experimental electric vehicle.

Steering Angle-Disturbance Observer (SA-DOB) Based Yaw Stability Control for Electric Vehicles with In-wheel Motors

Kanghyun Nam,Yunha Kim,Sehoon Oh 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

In this paper, a robust yaw stability control design based on active steering control is proposed for electric vehicles. The control system consists of an inner-loop controller (i.e., in this paper, called as a Steering Angle-Disturbance Observer(SA-DOB) which rejects an input steering disturbance and an output yaw disturbance simultaneously by feeding a compensation steering angle) and an outer-loop controller (i.e., PI-type Tracking Controller) to achieve the control performances. The control performance of the proposed yaw stability control system is verified through computer simulations and experiments.

AFS 시스템의 새로운 수학적 모델 및 제어기 개발

송정훈(Jeonghoon Song) 한국자동차공학회 2014 한국 자동차공학회논문집 Vol.22 No.6

A numerical model and a controller of Active Front wheel Steer (AFS) system are designed in this study. The AFS model consists of four sub models, and the AFS controller uses sliding mode control and PID control methods. To test this model and controller an Integrated Dynamics Control with Steering (IDCS) system is also designed. The IDCS system integrates an AFS system and an ARS (Active Rear wheel Steering) system. The AFS controller and IDCS controller are compared under several driving and road conditions. An 8 degree of freedom vehicle model is also employed to test the controllers. The results show that the model of AFS system shows good kinematic steering assistance function. Steering ratio varies depends on vehicle velocity between 12 and 24. Kinematic stabilization function also shows good performance because yaw rate of AFS vehicle tracks the reference yaw rate. IDCS shows improved responses compared to AFS because body side slip angle is also reduced. This result also proves that AFS system shows satisfactory result when it is integrated with another chassis system. On a split-m road, two controllers forced the vehicle to proceed straight ahead.

슬라이딩모드 컨트롤을 이용한 6WS/6WD 차량의 안전성 향상관한 연구

조완기(Wanki Cho),안상준(Sangjun An),이교일(Kyo Il Lee),이경수(Kyongsu Yi) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper presents steering control method by multiple sliding mode control to improve the vehicle stability in turning behavior. The controller is designed to control the side slip angle and the yaw rate by using the steering angle. The sliding mode control theory is used to consider parameter uncertainty in the vehicle. And the driver steering model is designed to follow a decided trajectory because the target vehicle to control is a unmanned ground combat vehicle. In this paper, it is assumed that information about the trajectory is known. The performance of controller is shown through the computer simulation using the 18 degree of freedom full vehicle model.

Direct Roll Moment Control for Electric Vehicles Based on Roll Angle Observer and Lateral Tire Force Control

K. Nam,S. Oh,H. Fujimoto,Y. Hori 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper presents roll stability control methodology for future personal electric vehicles with 4 wheel steering system and lateral force sensors. Direct roll moment control is realized by 4 wheel steering control based on lateral tire force control. In this paper, the lateral tire force, obtained from novel lateral force sensors, was utilized to estimate a roll angle and to control the vehicle roll motion. In order to estimate roll angle, a linear observer was proposed and implemented in an experimental electric vehicle. The effectiveness of a proposed roll angle observer was verified through field tests. By using an estimated roll angle, a direct roll moment controller for roll stability was designed based on general two-degree-of?freedom (2-DOF) control methodology. Effectiveness of a proposed roll stability control method was verified through computer simulation using CarSim software.

무인기용 착륙장치 측력 모델링 및 지상활주 제어기 설계

조성봉(Sung-Bong Cho),안종민(Jong-Min Ahn),허기봉(Gi-Bong Hur) 한국항공우주학회 2014 韓國航空宇宙學會誌 Vol.42 No.12

무인항공기의 자동이착륙을 성공적으로 수행하기 위해서는 자동 지상활주 제어는 반드시 설계되어야 하는 중요한 부분이다. 이러한 지상활주 제어기를 설계하기 위해서는 정확하고 신뢰도 높은 착륙장치 모델은 반드시 필요하다. 본 연구에서는 착륙장치 모델링을 완성하기 위해서 특별히 착륙장치 측력 모델링을 수행하였다. 조향각 명령을 포함한 Cornering Angle을 계산하여 측력을 모델링하였다. 그리고 모델링된 착륙장치 모델을 포함한 비선형 6자유도 시뮬레이션 환경을 이용하여, 항공기의 바람벡터 방향인 Course Angle 오차를 해소하기 위한 전륜 조향(Nose Wheel Steering)과 러더 조향(Rudder Steering)을 동시에 이용하는 자동 지상활주 제어기를 설계하였다. 설계된 지상활주 제어기를 동일하게 적용하여, 착륙장치 모델을 포함한 시뮬레이션 결과와 실제 무인기를 이용한 자동 지상활주 시험 결과를 비교하였고, 이로써 착륙장치 측력 모델링과 지상활주 제어기의 정확성을 입증하였다. This paper describes modeling process to obtain precise landing gear model which is necessary to design a control law for ground auto-taxi, auto take-off/landing of UAV. In this paper, landing gear side force modeling is studied to complete a landing gear model of UAV. Side force modeling is performed by calculating cornering angle including steering angle. And ground directional controller is designed by using nose wheel steering and rudder steering at the same time to control course angle error. Accuracy of landing gear side force modeling and ground directional controller is proved by comparing of auto-taxi test results with simulation results.

자율주행로봇의 주행 알고리즘을 위한 퍼지제어기의 설계

최한수,박경석 조선대학교 에너지.자원신기술연구소 2003 에너지·자원신기술연구소 논문지 Vol.25 No.1

Fuzzy controller does not derive special quality spinning expression for system, and uses rules by value expressed by language. It is used extensively to non-linear, plant which mathematical modelling is difficult etc... Fuzzy control algorithm of AMR that is used by this research applies obstacle position, distance of obstacle, Progress direction of robot, speed of robot, Perception area of sensor, etc.. by fuzzy control and decide steering angle of robot. An Autonomous Mobile Robot(AMR) performs duty by sensing a recognized situation and controlling suitably. The existing algorithm has some advantages that it is possible to express the obstacle exactly and the robot is sensitive to the change of environment. However, this algorithm, needs to control repeatedly according to the modelling and working environment that requires a great quantity of calculations. In this paper, We supplement shortcoming and designed direction algorithm of AMR using fuzzy controller. The existing algorithm has some advantages that it is possible to express the obstacle exactly and the robot is sensitive to the change of environment However, this algorithm needs to control repeatedly according to the modelling and working environment that requires a great quantity of calculations.

이동로봇 선회를 위한 Type-2 Fuzzy Self-Tuning PID 제어기 설계 및 조향각 제어

박상혁 ( Sang Hyuk Park ),최원혁 ( Won Hyuck Choi ),지민석 ( Min Seok Jie ) 한국항행학회 2016 韓國航行學會論文誌 Vol.20 No.3

이동로봇의 제어는 로봇 분야에 있어 중요한 이슈이다. 이동로봇의 자율주행은 다양한 작업 환경에서 중시되고 있다. 자율 주행을 위해 이동로봇은 장애물을 감지, 회피하며 지능시스템을 도입한 제어 방식들을 사용해 충돌회피의 성능을 보완하는 연구가 활발히 진행되고 있다. 본 논문에서는 이동 로봇의 기구학적 모델을 분석하고 조향각 제어를 위한 type-2 fuzzy self-tuning PID 제어기를 설계하였다. Type-2 fuzzy 제어기는 type-1 fuzzy 제어기와 달리 복수 개의 값을 가지므로 언어표현의 모호함의 자유도가 높다. 본 논문에서는 설계된 제어기와 기존의 PID 제어기, type-1 fuzzy self-tuning PID 제어기를 비교하기 위한 방법으로 MATLAB Simulink를 사용하여 시뮬레이션을 하였다. 시뮬레이션 비교 결과 기존의 PID제어기와 type-1 fuzzy self-tuning PID 제어기의 성능보다 type-2 fuzzy self-tuning PID 제어기의 성능이 우수하다는 것을 확인하였다. Researching and developing mobile robot are quite important. Autonomous driving of mobile robot is important in various working environment. For its autonomous driving, mobile robot detects obstacles and avoids them. Purpose of this thesis is to analyze kinematics model of the mobile robot and show the efficiency of type-2 fuzzy self-tuning PID controller used for controling steering angle. Type-2 fuzzy is more flexible in verbal expression than type-1 fuzzy because it has multiple values unlike previous one. To compare these two controllers, this paper conduct a simulation by using MATLAB Simulink. The result shows the capability of type-2 fuzzy self-tuning PID is effective.

Fuzzy Logic 제어를 이용한 AFS와 ARS의 통합제어에 관한 연구

송정훈(Jeonghoon Song) 한국자동차공학회 2014 한국 자동차공학회논문집 Vol.22 No.1

An Integrated Dynamics Control system with four wheel Steering (IDCS) is proposed and analysed in this study. It integrates and controls steer angle of front and rear wheel simultaneously to enhance lateral stability and steerability. An active front steer (AFS) system and an active rear steer (ARS) system are also developed to compare their performances. The systems are evaluated during brake maneuver and several road conditions are used to test the performances. The results showed that IDCS vehicle follows the reference yaw rate and reduces side slip angle very well. AFS and ARS vehicles track the reference yaw rate but they can not reduce side slip angle. On split-μ road, IDCS controller forces the vehicle to go straight ahead but AFS and ARS vehicles show lateral deviation from centerline.

능동전륜조향장치를 채택한 사륜조향차량의 횡방향 안정성 강화에 대한 연구

송정훈(Jeonghoon Song) 한국자동차공학회 2012 한국 자동차공학회논문집 Vol.20 No.2

This study is to propose and develop an integrated dynamics control system to improve and enhance the lateral stability and handling performance. To achieve this target, we integrate an AFS and a 4WS systems with a fuzzy logic controller. The IDCS determines active additional steering angle of front wheel and controls the steering angle of rear wheel. The results show that the IDCS improves the lateral stability and controllability on dry asphalt and snow paved road when double lane change and step steering inputs are applied. Yaw rate of the IDCS vehicle tracks reference yaw rate very well and body slip angle is reduced about by 50%. Response time of the IDCS vehicle is also decreased.