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Viewing 211 to 240 of 1648
2007-08-05
Technical Paper
2007-01-3573
Mai Li, Zong Changfu, Pan Zhao, Jiang Xiangping
With the development of the auto industry, the automobile manufacturers demand to shorten development period and reduce the cost. Compared with the traditional method, applying the virtual prototype is more economical. This paper presents a method for parameters sensitivity analysis and optimizing the performance of vehicle handling. The considered design parameters include suspension design parameters (the compliance parameters such as the stiffness of the spring, the kinematic parameters such as the coordinates of hard points in front, rear suspensions etc.), steering system design parameters (the inertia of steering wheel, the ratio of steering gear etc.), and operating parameters (the inertia and the coordinates of the center of the sprung mass, etc.). Finally the handling performances of the new designed vehicle are simulated by using the full vehicle ADAMS model.
2007-08-05
Technical Paper
2007-01-3572
Cao Youqiang, Luo Hong, Deng Zhaoxiang, Lai Fei
The influences among the weight number of object function, maximum value of suspension optimum control force and suspension performance are analyzed in this paper. A total state feedback controller for the 7-degree-freedoms modal of total vehicle based on random optimum control strategy is built. By ADAMS &MATLAB \simulink co-simulation, the influence of weight number of object function on maximum value of suspension control force and suspension performance is discussed in the paper. It obtains the relations among maximum value of suspension optimum control force, suspension performance and the variety of weight number Then a set of weight number which are applied to the object function of optimum control for the car are selected at last.
2007-08-05
Technical Paper
2007-01-3562
Balamurugan Janarthanam, Samir K. Ghodekar, Amol A. Apte
Abstract It is customary to select a twist beam rear suspension for front wheel driven small and medium range passenger cars. Besides better primary / secondary ride comfort, roll stiffness tuning ability, ease of assembly & good packaging solutions than the conventional semi trailing arm/ rigid axle suspensions, twist beam suspension system accentuate the concentration required in placing & orienting the cross beam to achieve certain imperative kinematical characteristics. In order to make the solutions of the required kinematical targets viable, it is vital to have the packaging space and stress concentration within yield limits given the weight & cost targets. This paper presents the work done on twist beam type suspension for a new generation entry level B-Class hatchback vehicle developed. To reduce the time consumed in validation of different design proposals a virtual validation process was developed.
2007-08-05
Technical Paper
2007-01-3561
Youngho Park, Jihwan Kim, Hyeong-cheol Lee
The paper presents a new offset compensation method of a yaw rate sensor and a lateral acceleration sensor. It is necessary to compensate the offsets of the analog sensors, such as the yaw rate sensor and the lateral acceleration sensor, to acquire accurate signals. This paper proposes two different offset compensation algorithms, the sequential compensation method and the model based compensation method. Both algorithms are combined with the algorithm map depending on the vehicle driving status. The proposed algorithm is verified by the computer simulations.
2007-08-05
Technical Paper
2007-01-3563
Shin-Ae Lee, Byung-Hak Kwak
Vehicle stability control system can enhance the vehicle stability and handling in emergency situation through the control of traction and braking forces at the individual wheels. In order to achieve the desired performance, we must exactly calculate compensated yaw moment, and control the wheel slip rate to generate braking force. However, the yaw moment is highly dependent on the status of tire dynamics at each wheel. In this study, we propose optimal yaw moment distribution controller based on tire model according to the normal forces, the road condition, the slip rate and the slip angle to cope with nonlinear tire dynamics. The proposed controller for distributing the desired tire slip rate makes used of the optimization technique based on the tire nonlinear model. It minimizes the braking control force corresponding to the desired tire slip at each wheel.
2007-08-05
Technical Paper
2007-01-3566
Young-Joo Cho, Byung-Hak Kwak
Because of an increasing popularity of the SUV and Light Truck with an elevated center of gravity, the rollover propensity is higher than before. This paper proposes a method to detect and prevent an impending rollover of the vehicle using Electronic Stability Control(ESC). The Rollover Prevention(ROP) function determines a rollover critical situations based on the rollover propensity index and generates a proper activation through a brake and engine intervention. The rollover propensity index is calculated from the relative distance of the trajectory to the threshold on the phase plane of roll-angle and roll-rate. The threshold on the phase plane is deduced from the conservation of energy in the roll model. For the detection and activation of continuous rollover phenomena, we use the TTL concept that presents a gradually increasing rollover propensity. The proposed algorithm in this paper is shown to be effective in mitigating a rollover through the simulation and vehicle test.
2007-08-05
Technical Paper
2007-01-3560
Jihwan Kim, Hyeongcheol Lee
This paper presents a model based sensor fault detection and isolation algorithm for the vertical acceleration sensors of the Continuous Damping Control (CDC) system, installed on the sprung mass. Since sensor faults of CDC system have a critical influence on the ride performance as well as the vehicle stability, the sensor fault detection algorithm must be implemented into the overall CDC algorithm. In this paper, each vertical acceleration sensor installed on the sprung mass (two in the front corners and one in the rear) separately estimates the vertical acceleration of the center of gravity of the sprung mass. Then, the sensor fault is detected by cross-checking all three vertical acceleration estimates independently obtained by the each vertical acceleration sensor.
2007-08-05
Technical Paper
2007-01-3558
Lei Li, Changgao Xia, Wei Qin
Taking the five-link suspension of a car as the subject investigated on the basis of ADAMS/Car, this paper builds the parameterized mode of the multi-link suspension. The simulation shows the influence relations among multi-link suspension structure parameter and the wheel location parameter, wheel track, roll center. On the base of this, aim for improving the ride safety and comfort, multi-link suspension optimization model is built and carried out parameter optimization design by using ADAMS/Insight. The result shows that this method is high-performance and can be used in the design of multi-link suspension conveniently.
2007-08-05
Technical Paper
2007-01-3748
JoyantaKumar Chakrabarty
During endurance tests on new prototypes, it is often observed that test drivers come back with some feed back on clutch slippage. This is a typical example of subjective evaluation and at times it is found that it is the test driver's perception rather than the actual clutch slippage. To over come this problem, a new method has been evolved which captures the clutch slippage automatically and quantify that to the minutest details. This is achieved using GPS based instrumentation and software for automatic detection. This system is part of intelligent control which using the GPS determines the actual speed of the vehicle and also acquires the engine speed through RPM sensor which is converted into vehicle speed. Using a dedicated software program, variation in actual speed and calculated speed provides the information on clutch slippage along with the gear shift pattern during test driving.
2007-08-05
Technical Paper
2007-01-3745
Jaesoon Park, Taeoh Tak, Mingu Kuk, Daehee Kim, Seungeon Shin
A retractor is the major component of a seatbelt system that restraints passengers by locking the movement of webbing. Recently, in order to increase the effectiveness of seatbelt systems, motorized retractors that remove slack and correct passenger posture just before airbag expansion when collision is predicted are widely used. Key component of motorized retractors is the one-way clutch that engages and disengages the winding action of webbing according to the direction of motor revolution. Analytical investigation of action of the one-way clutch mechanism has been carried out to figure out conditions for one-way locking, and to study the effect of various kinematic and dynamic design variables of one-way clutch. Using combination of ADAMS and LifeMOD softwares, dynamic simulation of operation of motorized retractors including Hybrid-III dummy model has been carried out to evaluate the performance of the motorized retractors in various crash scenarios.
2007-08-05
Technical Paper
2007-01-3725
I. V. Balabin, V. V. Bogdanov
This paper summarizes the result of the bumper's role investigation in the process of reducing the energy-absorbing level during frontal collisions of vehicle. The paper is citing the detailed review and analysis of the stages of bumper's construction evolutions from the point of view of realizing of the passive safety's functions for frontal collision. Also the paper cites the examples of FEM-calculations of the front bumper's panel with the purpose of discovering the fields of strains and deformations. The paper is based on the research performed by the authors for discovering the optimal areas of variation of the bumper's rigidity and mass and, as a result, the construction of impact-safety bumper patented in Russia. The paper contains the recommendations on further bumper's transformations into an impact-safety and trauma-free device for vehicles and pedestrians.
2007-08-05
Technical Paper
2007-01-3585
Daeyi Jung, Dohyun Jung, Changhyun Jeong, Youseok Kou, Huei Peng
The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situations including the worst cases such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they are not enough to predict other possible worst case scenarios. Therefore, it is crucial to search for the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios in terms of rollover and its application in simulation basis. The human steering angle is selected as a design variable and optimized to maximize the index function to be expressed in terms of vehicle roll angle. The obtained scenarios were enough to generate the worse cases than NHTSA ones.
2007-08-05
Technical Paper
2007-01-3584
Kihan Noh, Daeyi Jung, Hyungjeen Choi, Kyoungsu Yi
It is significant to consider human factors for the design of the intelligent safety vehicle beyond the general vehicle's performance. Therefore, the development of an ergonomic driver model to imitate the human driving pattern is essential for the advanced vehicle research considering the human factors. In this paper, several tests for the study of the human factors are conducted, and the control logic to describe the human driving pattern is presented. First of all, human factors to influence a vehicle operation are assumed to be consisted of two major components, the preview distance and the human neuromuscular response. Secondly, the control logic is consisted of the finite preview optimal control algorithm to account for human factors mentioned previously. Finally, the ergonomic driver model is developed based on these and simulated with Carsim software in SIMULINK environment.
2007-08-05
Technical Paper
2007-01-3580
Daesik Kim, Sungwoo Kim, Hyungjin Kim, Bongsoo Son
The “Road Safety Information System(RSIS)” addressed in this paper differs from those active and real time systems in that it controls an artificial counter force at the active accelerator pedal before the vehicle actually enters the curve to limit the cornering speed. This study aims at detecting the dangerous section on the road and warning of entering the curve. To determine dangerous section, the quality and accuracy of Digital Road Map(DRM) is very important to calculate the curve fitting on the road. The curve detection algorithm and software, which were suggested by in this paper, with effective determination were designed and developed. As a result of the research, when this method were used to find curve section it showed similar results and performances between a highway and national road.
2007-08-05
Technical Paper
2007-01-3589
Hidehiko Enomoto, Kouhei Akiyama, Hirokazu Okuyama
Large truck accidents sometimes result in severe damages or give large disturbance of traffic and there are demands of improving vehicle safety characteristics. Main types of traffic accidents concerned are rear-end collision and single accident. As countermeasures for rear-end collisions, world-first collision mitigation brake for commercial vehicles; Pre-crash Safety System, was developed. If there is possibility of collision, warning to driver and brake control intervention is carried out in stepwise fashion and collision speed is decreased. To achieve higher effect in collision mitigation, it is necessary to activate warning or brake-force in earlier timing. Inter-vehicle or infrastructure-vehicle communication offer promising prospect. Tractor-trailer combinations show some instable behaviors. “Roll Stability Assist” and “Vehicle Stability Control” were developed to assist drivers to avoid the occurrence of these instable behaviors.
2007-08-05
Technical Paper
2007-01-3594
Weigao Qiao, Xicheng Wang
Based on the multi-body system, the work research the injury index of the mathematics models of pedestrian, by simulating the motion of the pedestrian impacted by vehicle using MADYMO. Compared with the article published, verify the dependability of this simulated test. Based on the dependability, Carry on sensitivity analysis to design parameter of the automobile. Research on the pedestrian protection by the vehicle by revising the sensitive design parameter. By simulating the pedestrian impacted by the vehicle which installing the hood raise structure, search on the injury index. Compared with the original injury index, we can find that the hood raise structure be propitious to the pedestrian.
2007-08-05
Technical Paper
2007-01-3590
Yuta Takimoto, Pongsathorn Raksincharoensak, Masao Nagai
This paper proposes a driving torque control algorithm of micro-scale electric vehicle (NOVEL-I) at the scene of preceding vehicle following. First, an inter-vehicle distance controller aiming to keep a safe inter-vehicle distance is designed. Next, the experiments of vehicle following situation by automatic driving with the designed controller are realized and the effectiveness of the controller is verified. Next, the designed controller is applied to the human-vehicle closed-loop system as driver assistance systems, thereby enhancing driving comfort and reducing driving workload for human. Finally, the experiment of vehicle following by cooperative driving between the human and the controller is conducted. The experimental result in cooperative driving is compared with manual driving, and the effectiveness of the controller is verified.
2007-08-05
Technical Paper
2007-01-3638
Mark Shaw
The US requirement for tire pressure monitoring systems (TPMS) will reach the 100% installation rate this year in accordance with the requirements of FMVSS138 promulgated by the NHTSA. The wide variety of semiconductor technologies available now for direct TPMS can solve the requirements for these systems. However, the wide variation in solutions for TPMS can present a number of end customer issues when there are no standard methods or protocols used in their application. This paper will present an advanced TPMS sensor that includes all of the required features for very complex solutions and presents the issues that result from too many variations in the field. Finally a set of suggested protocols are presented that could help reduce the field issues that may be experienced by the end customer.
2007-08-05
Technical Paper
2007-01-3639
Mou Xiangdong
To further improve the travels stabilization and steering characteristics of vehicle, people pay more attention on the steering affect of suspension. Various possess steering function of suspension system on car one after another change into more perfect. The compliance suspension is in among. In this paper it has analysis to steering character of Citroën-ZX series cars compliance suspension. The compliance suspension has been specially research on the affect of probe into roll-steering character to car's handling performance and it has drawn a preliminary conclusion.
2007-08-05
Technical Paper
2007-01-3636
Er. Neeraj Singh Gautam, Prashant Awadhiya
This is a proposed alternative to the Ackermann Steering Mechanism. Synthesis of a six member mechanism taking seven precision points is performed for an automotive steering mechanism. The maximum rotation of inner wheel is taken as 65 degree to attain still less turning radius. The mechanism has been compared with those achieved by Ackerman Steering Mechanism (ASM), Fahey Eight Member Mechanism (FEMM) and Pramanik Six Member Mechanism (PSMM). The suggested mechanism gives fairly the accurate result that falls above the ASM mechanism. The mechanism gives better end response leading to shorter turning radius.
2007-08-05
Technical Paper
2007-01-3637
Ren He, Yong-tao Wang, Ying-sheng Zhao
The math model of united brake system is set up on thinking of the influence of the coefficient of the revolving mass changes to linear mass of vehicle, the efficiency of slippage and so on. The simulation model is set up in the Simulink module of Matlab. The result of simulation shows that the braking distance is shortened by the function of united brake system in the emergency brake; the braking ability of the bus is improved. The united brake system can also be used to stop the bus in the nonemergercy brake. The retarder exhausts most of energy of automobile. Thus, the maintenance cost is reduced. The bus can run at steady and economic speed on the hillside path with continuous brake of united brake system.
2007-08-05
Technical Paper
2007-01-3646
Kubilay Yay, I.Murat Ereke
In this paper, first of all, after load distribution of the front and rear axles of domestic midi bus have been measured, force on the parabolic springs of the front axle was calculated. Level of the good, middle and bad roads of Adana city in south of Turkey were determined and strain and displacement data have been recorded from connected strain-gage and LVDT sensors on the front axle parabolic springs of the midi bus. Test mechanism of the front axle suspension system connected chassis like midi bus was assembled in the laboratory. Recorded road roughness displacement, strain, and brake force strain data of the parabolic spring were processed by LMS Tecware, n-code ICE-flow 4.0 and special written computer program for this accelerated life cycle project. In addition to this, rainflow analysis, cumulative damage values, appending brake signals data in these different roads and every road damages have been calculated.
2007-08-05
Technical Paper
2007-01-3642
Daofei Li, Fan Yu
To optimally allocate control authorities to co-existing active actuators, an integrated chassis controller with main/servo-loop structure is designed to coordinate direct yaw moment control and active steering. Firstly, a sliding mode controller in the main-loop calculates the desired stabilizing forces. Then in the servo-loop, by directly considering limits of road friction and actuators, a quadratic programming based control allocation approach is adopted to reasonably and optimally distribute these deisired forces to tire actuator actions. Co-simulation of Matlab/Simulink and Carsim clarifies that the proposed controller could significantly improve vehicle handling performances.
2007-08-05
Technical Paper
2007-01-3650
Hongyu Zheng, Changfu Zong, Tianjun Zhu, Chengwei Tian
Electro-Hydraulic Brake (EHB) system is a kind of active control brake systems of automobile, the pedal from the calipers actuation separated and no longer limited by conventional hardware. The system may come together with ABS, ESP, and ASR function, also the communication with other systems is done via the CAN network. EHB system may be classified a “stepping stone” technology to full brake-by-wire and brings huge transform for the performance of braking system. In this paper, vehicle dynamic models were established and accomplished the control strategy for vehicle stability control with EHB system which can adjust wheel and vehicle motion, improve the lateral and longitudinal vehicle stability. This result was verified by simulation which shows that the controller is effective on improving the vehicle stability.
2007-08-05
Technical Paper
2007-01-3652
Yang Shengbing, Den Chunan, Ji Xuewu, Chen Kuiyuan
A steer-by-wire system has many benefits over conventional steering system for no mechanical link existing between the steering wheel and the road wheels. Road feeling has been being one of the most important vehicle characteristics reflecting vehicle directional control and stability. Besides the steering angle, road wheels reactive torque and vehicle dynamical behavior are considered in this paper. A control strategy with road wheels force feedback and steering wheel angle feedback was developed. The vehicle dynamic states are taken into account for road feeling simulation. Simulation shows that the control strategy achieves desired road feeling, and the second control strategy can improve the road feeling dynamically.
2007-08-05
Technical Paper
2007-01-3648
Maotao Zhu, Bing Han
Aluminum disc wheels have to pass impact test before going into production. Impact test of “15×6J” wheel is analyzed with CAE technology, representing the application of finite element method on simulation of impact problems. In numerical simulation of wheel impact test, integrated finite element model is established, including impact block, wheel, tyre and bracket. The whole process of impact is simulated, and velocity and displacement curves of impact block and wheel stress distribution are obtained. The analysis results indicate the wheel can pass the impact test, which is validated by the physical experimentation.
2007-08-05
Technical Paper
2007-01-3657
Young Ok Lee, Choong Woo Lee, Han Byul Chung, Chung Choo Chung, Youngsup Son, Paljoo Yoon, Inyong Hwang
This paper presents three types of controllers for Electric Parking Brake (EPB) Systems: bang-bang, linear proportional (P), and nonlinear proportional (P) controller. Mechanical and electrical parts of EPB system are modeled and implemented using Modelica language. There is good agreement between simulation and experimental results. For the stability analysis, the EPB system is modeled as a state-dependent switched system with simplified friction dynamics. From simulation and experimental results, it turns out that the nonlinear P controller provides good uniformity in performance and robustness among them.
2007-08-05
Technical Paper
2007-01-3658
Seongjoo Kim, Jonghyun Pyo
Good road feel means that the driver can interpret road conditions through the steering wheel. This is one of the most important requirements demanded by car makers. However, over-sensitivity in steering transmission could cause inconvenience to the driver especially maneuvering on rough roads and hence must be isolated by the steering system or by other means. To overcome this, firstly we have to distinguish diverse road conditions and apply appropriate control strategy. In this paper we've proposed two control strategies to enhance steering performance on rough roads. The first method analyzes motor position signal of Electric Power Steering (or EPS) where the road roughness is separated from the motor position signal through signal processing. The roughness then is compensated for by using EPS to obtain a better steering feel. The second method utilizes CAN transferred vehicle information from Continuous Damping Control system (or CDC).
2007-08-05
Technical Paper
2007-01-3654
Wang Ruo-Ping
The dynamic characteristics of the hydraulic power steering system(HPSS) are simulated and discussed with SIMULINK software and hydraulic control theory. The characterristic of software SIMULINK is introduced and the dynamical model of valve-controlled hydraulic cylinder is constructed. The dynamic simulation can be made by establishing the dynamic model and the simulation model of HPSS, initializing the parameters of the system, and implementing the dynamic simulation. Lastly, the key factors affecting the dynamic characteristics of HPSS are discussed. The simulation result can provide theoretical basis for designing HPSS and the SIMULINK method is an effective way to simulate the dynamical characteristics of HPSS.
2007-08-05
Technical Paper
2007-01-3660
Han Byul Chung, Youngsup Son, Paljoo Yoon, Choong Woo Lee, Doo Ho Lee, Young Ok Lee, Chung Choo Chung
A fault detection method with parity equations is proposed in this paper. Due to low cost implementation, the velocity of a motor is not measurable in EPB systems. Therefore, residuals are not reliable with a low resolution encoder to estimate the motor velocity. In this paper, we propose a fault detection method with sensorless estimation using current ripples. The method estimates position and velocity of the motor by detecting periodical oscillations of the armature current caused by rotor slots. This method could estimate position and velocity of the motor with less computational effort than a state observer. Moreover, the method is less sensitive to motor parameters than model-based estimation methods. The effectiveness of this method is validated with experimental data. The simulation results show that various faults have their own residual patterns. Therefore, we could detect the fault by monitoring the residual signals.
Viewing 211 to 240 of 1648