Chassis Control based on Fuzzy Logic

International audienceBased on a Global Chassis Control system with three-layers architecture (decision, control, and physical layers) a Fuzzy Logic (FL) approach is exploited. The FL based decision layer identifies the current driving condition of the vehicle and decides the control strategy to take care of this driving condition. A confusion matrix validates the classification results. The control strategy is implemented through the subsystems (suspension, steering, and braking) at the FL based control layer. The strategy was evaluated under two different tests: slalom and double line change by comparing the performance with an UnControlled system. Early results show the proposed strategy has less roll, yaw movement and side slip angle than an UnControlled system during a double line change maneuver; also, for the slalom test the proposal improves the dynamic vehicle performance allowing the driver to maintain the vehicle under control

Proceedings of the 4th field robot event 2006, Stuttgart/Hohenheim, Germany, 23-24th June 2006

Zeer uitgebreid verslag van het 4e Fieldrobotevent, dat gehouden werd op 23 en 24 juni 2006 in Stuttgart/Hohenhei

Urban and extra-urban hybrid vehicles: a technological review

Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid –electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used

Designing Software Architectures As a Composition of Specializations of Knowledge Domains

This paper summarizes our experimental research and software development activities in designing robust, adaptable and reusable software architectures. Several years ago, based on our previous experiences in object-oriented software development, we made the following assumption: ‘A software architecture should be a composition of specializations of knowledge domains’. To verify this assumption we carried out three pilot projects. In addition to the application of some popular domain analysis techniques such as use cases, we identified the invariant compositional structures of the software architectures and the related knowledge domains. Knowledge domains define the boundaries of the adaptability and reusability capabilities of software systems. Next, knowledge domains were mapped to object-oriented concepts. We experienced that some aspects of knowledge could not be directly modeled in terms of object-oriented concepts. In this paper we describe our approach, the pilot projects, the experienced problems and the adopted solutions for realizing the software architectures. We conclude the paper with the lessons that we learned from this experience

Smart Traction Control Systems for Electric Vehicles Using Acoustic Road-type Estimation

The application of traction control systems (TCS) for electric vehicles (EV) has great potential due to easy implementation of torque control with direct-drive motors. However, the control system usually requires road-tire friction and slip-ratio values, which must be estimated. While it is not possible to obtain the first one directly, the estimation of latter value requires accurate measurements of chassis and wheel velocity. In addition, existing TCS structures are often designed without considering the robustness and energy efficiency of torque control. In this work, both problems are addressed with a smart TCS design having an integrated acoustic road-type estimation (ARTE) unit. This unit enables the road-type recognition and this information is used to retrieve the correct look-up table between friction coefficient and slip-ratio. The estimation of the friction coefficient helps the system to update the necessary input torque. The ARTE unit utilizes machine learning, mapping the acoustic feature inputs to road-type as output. In this study, three existing TCS for EVs are examined with and without the integrated ARTE unit. The results show significant performance improvement with ARTE, reducing the slip ratio by 75% while saving energy via reduction of applied torque and increasing the robustness of the TCS.Comment: Accepted to be published by IEEE Trans. on Intelligent Vehicles, 22 Jan 201

Comparison of the ride performance of an integrated suspension model

Vehicle suspension is one of the important components to reduce vibration from the road. The vehicle seat suspension acts as another component to provide ride comfort, especially to reduce driver fatigues for long hour’s driving. In this paper, the ride comfort is therefore studied based on the integrated suspension model which includes vehicle chassis suspension, seat suspension and driver model. A four-DOF mathematical model is presented. The hydraulic actuator is introduced as well. Three controllers, including skyhook damper control, slide model control (SMC) and fuzzy logical control (FLC), are applied to the semi-active/active suspension with passive seat suspension. To improve the ride comfort further, combination the best performance of ride comfort from active chassis suspension, the semi-active seat suspension is then designed. The ride performance is evaluated based on driver deformation and acceleration

A Study on the Shifting Control Logic for Automated Manual Transmission using Artificial Intelligence Techniques

In the domestic commercial vehicle market, there is an increase of demand on the automated multistep manual transmission but the study and development on the transmission have not proceeded further yet. As a result, the transmission has been entirely imported from overseas suppliers by paying high cost and it is applied to the commercial vehicles. Therefore, on this study it’s expected that the study of shifting control logic, which is the core technology in the automated manual transmission, contributes to the industry in the domestic market. Study method and scope have been defined and analyzed through the benchmarking of overseas suppliers’ automated manual trans- mission. And with these analysis results, study orientation of shifting control logic on automated manual transmission has been set up as the final goal. After the requirements of shifting control logic have been defined through the detail study and data analysis on the transmission system operation and actuator control, each S/W module was constructed in order to do control and signal conditioning applying model-based S/W development method for the requirements of automated manual transmission control. S/W module has been developed as three modules which are shifting control logic, clutch control module, and shifting actuator control module. For each module, SILS(Software In the Loop Simulation) has been performed and its designed results have been checked and updated. And shifting timing setup of shifting control logic, which is the main topic on this study, has been designed with artificial intelligence techniques instead of shifting map which is applied according to Loop-up table type. The test of the designed S/W has been performed and checked on test bench with functions of multistep automated manual transmission after integrating both high level layer S/W, which is shifting control logic, and low level layer S/W, which is firmware and device driver, into TCU. And after installing automated manual transmission built with TCU in the high performance commercial vehicle, the driving test has been performed under chassis dynamometer and the acquired data from test has been checked and analyzed. With the analyzed results, it has been checked whether or not control logic requirements are consistent. And after evaluating satisfaction status of control performance target, it was confirmed that the additional study was needed. At this research from analysis of requirements to chassis dynamometer test, the study results came out as follows. First, torque relation at each gear-shifting was confirmed via modeling results of multistep automated manual transmission. And contents for control logic and transmission operation were analyzed with data from TCU connected with sensors, solenoid valves, and CAN communication through benchmarking. With these analyzed results, specification and design target were defined to implement TCU S/W. Second, shifting control logic and shifting map based on fuzzy control algorithm were designed for 12 speed shifting control system of automated manual transmission and clutch control system applying model-based S/W development method. The designed shifting control logic and intellectual gear-shifting map were applied to TCU S/W and satisfaction of the design target was confirmed through SILS and vehicle test using chassis dynamometer. Thirds, in particular the design of gear-shifting map using fuzzy control algorism consists of up shifting timing and down shifting timing by throttle and gear-step inputs. In vehicle driving test on chassis dynamometer, analysis results of up and down shifting timing indicated that shifting performance was superior to shifting map applied with look-up table. Thus, the design target was satisfied. Evaluation on shifting control logic and shifting map based on fuzzy control algorithm was done under condition of normal driving mode on chassis dynamometer. Therefore, many tests and evaluations on chassis dynamometer and on real road are indeed required after applying shifting control logic and shifting map on TCU S/W. And the various studies are continually done in order to improve and solve the error and problem of shifting control logic and shifting map given from the test results.제 1 장 서 론 1 1.1 연구 배경 및 목적 1 1.2 연구 방법 및 범위 2 1.3 논문의 구성 3 제 2 장 인공지능 이론 5 2.1 퍼지 이론 6 2.2 퍼지 추론 8 2.3 퍼지 제어기 11 제 3 장 다단 자동화 수동변속기 시스템 16 3.1 다단 자동화 수동변속기 구조 16 3.2 다단 자동화 수동변속기 모델링 18 3.3 다단 자동화 수동변속기 분석 27 3.4 변속 제어로직 설계 요구사항 41 제 4 장 인공지능 기법을 이용한 변속 제어로직 설계 45 4.1 다단 자동화 수동변속기 시스템 제어 설계사양 46 4.2 모델 기반 변속 제어로직 설계 52 4.3 퍼지 제어 알고리즘을 이용한 변속맵 설계 85 제 5 장 변속 제어로직에 관한 시험 및 고찰 105 5.1 변속 제어로직 관련 시험목표 106 5.2 SILS 및 차대동력계 이용 시험방법 109 5.3 변속 제어로직 관련 시험결과 113 제 6 장 결 론 130 참고문헌 13

Identification of Dynamics of Movement of the Differential Mobile Robotic Platform Controlled by Fuzzy Controller

Mobile robots with differential chassis are very often used because of simple construction and a smaller number of drive and sensors elements. For practical applications, it is necessary to know the kinematic and dynamic structure of the differential mobile robot. This paper deals with identification of the dynamics of the differential robotic platform, using differential kinematics. Electro-optical rpm sensors obtain required values such as speed of the driven wheels. Identification of dynamic system is used to determine the dynamic characteristics of power subsystem of developed EN 20 robot, whose control subsystem is created by single-chip microcontroller. Response of the dynamic system is monitored along with the peripheral velocity of the right and left drive wheels. Incremental encoders that work on optics principle measure the speeds of both wheels. It was necessary to calibrate the sensors and obtain constants for precise speed determination. The monitored system with the dumped oscillation characteristic is approximated by a system with the inertia of the 2nd order. Dynamic system parameters are found. The system approximation is suitable for given evolution of circumferential speeds of the right and left wheels. This is confirmed by the quantitative determination coefficients R2. The equations for calculating peripheral velocities of driving wheels are applied to the system of the differential equations for the differential chassis. A mathematical model of the mobile robot EN20 was obtained for testing control algorithms, where a robot is equipped with sensory systems and it is designed for interior conditions. Fuzzy controller with 49 interference rules is used to control the mobile robot. The real mobile robot path matches the path determined according to simulation model

The impact of synthetic biology in chemical engineering - Educational issues

This paper describes the development of syntheticbiology as a distinct entity from current industrial biotechnology and the implications for a future based on its concepts. The role of the engineering design cycle, in syntheticbiology is established and the difficulties in making and exact analogy between the two emphasised. It is suggested that process engineers can offer experience in the application of syntheticbiology to the manufacture of products which should influence the approach of the synthetic biologist. The style of teaching for syntheticbiology appears to offer a new approach at undergraduate level and the challenges to the education of process engineers in this technology are raised. Possible routes to the development of syntheticbiology teaching are suggested

Global Chassis Control System Using Suspension, Steering, and Braking Subsystems

A novel Global Chassis Control (GCC) system based on a multilayer architecture with three levels: top: decision layer, middle: control layer, and bottom: system layer is presented. The main contribution of this work is the development of a data-based classification and coordination algorithm, into a single control problem. Based on a clustering technique, the decision layer classifies the current driving condition. Afterwards, heuristic rules are used to coordinate the performance of the considered vehicle subsystems (suspension, steering, and braking) using local controllers hosted in the control layer. The control allocation system uses fuzzy logic controllers. The performance of the proposed GCC system was evaluated under different standard tests. Simulation results illustrate the effectiveness of the proposed system compared to an uncontrolled vehicle and a vehicle with a noncoordinated control. The proposed system decreases by 14% the braking distance in the hard braking test with respect to the uncontrolled vehicle, the roll and yaw movements are reduced by 10% and 12%, respectively, in the Double Line Change test, and the oscillations caused by load transfer are reduced by 7% in a cornering situation