Development of an Anti-Lock Brake System for Motorcycle

SUMMARY

An Anti-Lock Brake System (ABS) system is developed for motorcycles using different control laws to improve the safety during emergent braking conditions. The mechanical design problem is first investigated so as to modify a scooter to be equipped with the proposed ABS brake system and to set up experimental test stand. For ABS control, the slip control, P1R3, and P2R4 methods are used to implement the controller using an Intel 80196KC single chip microcomputer. The hard-ware-in-the-loop (HITL) simulation is also performed in PC to check the performance in various road conditions including dry and wet roads. It is found experimentally that both P1R3 and P2R4 can both achieve ABS function, but P2R4 performs more desirably than P1R3 method.     

气压ABS系统流量特性的实验研究

开发了气压ABS电磁阀测试系统，建立了气室充、放气过程压力变化的微分方程，结合两者研究了气压ABS系统的流量特性，获得了某中型客车ABS系统在不同情况下的流量系数。讨论了ABS电磁阀的结构参数和动作频率对整个系统流量特性的影响，并得到了几种典型动作频率下的流量系数。建立的气室压力模型和所求得的流量系数为气压ABS控制逻辑的设计提供了依据。     

Prediction of antilock braking system condition with the vehicle stationary using a model-based approach

An Antilock Braking System (ABS) is one of the most important safety facilities equipped in modern vehicles. A self-test is therefore embedded into its ECU to identify any electronic malfunction. However there is no effective method to predict or check its mechanical conditions routinely to ensure its functionality. Because the ABS system is merely actuated above a particular speed in emergency stops, the current brake test facilities are not adequate for ABS test. Because of the dangers involved it would not be acceptable to use a public road to implement such a practice for fault detection so an alternative means must be sought. To provide a safe and convenient solution this paper proposes a novel method to predict ABS faults whilst the vehicle is stationary. In this situation a model-based approach is applied to predict various faults from the ABS, especially from its hydraulic subsystem. As such, a mathematic model is developed to describe the operating processes of ABS including possible faulty conditions. An autonomous control strategy is also designed to actuate the control module independently without the knowledge of the control algorithms embedded in an ABS control module. This approach is evaluated through a Simulink simulation.     

Feedforward and Crone Feedback Control Strategies for Automobile ABS

Summary As mechatronic subsystems and especially new emerging technologies for brake systems are more and more developed, a new control architecture for ABS is proposed. The control architecture is designed using both feedback and feedforward controls that command pressure-controlled proportional servo-valves. The methods are developed to compensate for the uncertainty associated with the state of the road surface. The advantages of this strategy compared to the existing ABS strategy are discussed including simulations results using a complete vehicle and brake system model.     

Feedforward and Crone Feedback Control Strategies for Automobile ABS

Summary As mechatronic subsystems and especially new emerging technologies for brake systems are more and more developed, a new control architecture for ABS is proposed. The control architecture is designed using both feedback and feedforward controls that command pressure-controlled proportional servo-valves. The methods are developed to compensate for the uncertainty associated with the state of the road surface. The advantages of this strategy compared to the existing ABS strategy are discussed including simulations results using a complete vehicle and brake system model.     

防抱死制动系统模糊自学习控制研究

由于车辆参数和运行工况的复杂多变，针对特定参数和路面条件所设计的防抱死制动系统往往难以适应。为解决这一问题，文中首先建立了带有盘式制动器的双轮车辆直线制动系统的数学模型；而后提出了模糊自学习控制策略，该方案通过引入模糊学习机制以调整模糊控制器的规则集，可使车辆对象输出跟踪理想参考模型的输出；接着对所设计控制算法在不同路面条件下进行了性能模拟；最后开发了模糊自学习微控制器，基于硬件在环仿真技术，对设计控制器的性能进行了实验验证。     

Improvement of drivability and fuel economy with a hybrid antiskid braking system in hybrid electric vehicles

When braking on wet roads, Antilock Braking System (ABS) control can be triggered because the available brake torque is not sufficient. When the ABS system is active, for a hybrid electric vehicle, the regenerative brake is switched off to safeguard the normal ABS function. When the ABS control is terminated, it would be favorable to reactivate the regenerative brake. However, recurring cycles from ABS to motor regenerative braking could occur. This condition is felt to be unpleasant by the driver and has adverse effects on driving stability. In this paper, a novel hybrid antiskid braking system using fuzzy logic is proposed for a hybrid electric vehicle that has a regenerative braking system operatively connected to an electric traction motor and a separate hydraulic braking system. This control strategy and the method for coordination between regenerative and hydraulic braking are developed. The motor regenerative braking controller is designed. Control of regenerative and hydraulic braking force distribution is investigated. The simulation and experimental results show that vehicle braking performance and fuel economy can be improved and the proposed control strategy and method are effective and robust.     

Experimental investigations on continuous regenerative anti-lock braking system of full electric vehicle

Functions of anti-lock braking for full electric vehicles (EV) with individually controlled wheel drive can be realized through conventional brake system actuating friction brakes and regenerative brake system actuating electric motors. To analyze advantages and limitations of both variants of anti-lock braking systems (ABS), the presented study introduces results of experimental investigations obtained from proving ground tests of all-wheel drive EV. The brake performance is assessed for three different configurations: hydraulic ABS; regenerative ABS only on the front axle; blended hydraulic and regenerative ABS on the front axle and hydraulic ABS on the rear axle. The hydraulic ABS is based on a rule-based controller, and the continuous regenerative ABS uses the gain-scheduled proportional-integral direct slip control with feedforward and feedback control parts. The results of tests on low-friction road surface demonstrated that all the ABS configurations guarantee considerable reduction of the brake distance compared to the vehicle without ABS. In addition, braking manoeuvres with the regenerative ABS are characterized by accurate tracking of the reference wheel slip that results in less oscillatory time profile of the vehicle deceleration and, as consequence, in better driving comfort. The results of the presented experimental investigations can be used in the process of selection of ABS architecture for upcoming generations of full electric vehicles with individual wheel drive.     

A vehicle ABS adaptive sliding-mode control algorithm based on the vehicle velocity estimation and tyre/road friction coefficient estimations

A sliding-mode observer is designed to estimate the vehicle velocity with the measured vehicle acceleration, the wheel speeds and the braking torques. Based on the Burckhardt tyre model, the extended Kalman filter is designed to estimate the parameters of the Burckhardt model with the estimated vehicle velocity, the measured wheel speeds and the vehicle acceleration. According to the estimated parameters of the Burckhardt tyre model, the tyre/road friction coefficients and the optimal slip ratios are calculated. A vehicle adaptive sliding-mode control (SMC) algorithm is presented with the estimated vehicle velocity, the tyre/road friction coefficients and the optimal slip ratios. And the adjustment method of the sliding-mode gain factors is discussed. Based on the adaptive SMC algorithm, a vehicle's antilock braking system (ABS) control system model is built with the Simulink Toolbox. Under the single-road condition as well as the different road conditions, the performance of the vehicle ABS system is simulated with the vehicle velocity observer, the tyre/road friction coefficient estimator and the adaptive SMC algorithm. The results indicate that the estimated errors of the vehicle velocity and the tyre/road friction coefficients are acceptable and the vehicle ABS adaptive SMC algorithm is effective. So the proposed adaptive SMC algorithm can be used to control the vehicle ABS without the information of the vehicle velocity and the road conditions.     

Transient switching control strategy from regenerative braking to anti-lock braking with a semi-brake-by-wire system

Regenerative braking is an important technology in improving fuel economy of an electric vehicle (EV). However, additional motor braking will change the dynamic characteristics of the vehicle, leading to braking instability, especially when the anti-lock braking system (ABS) is triggered. In this paper, a novel semi-brake-by-wire system, without the use of a pedal simulator and fail-safe device, is proposed. In order to compensate for the hysteretic characteristics of the designed brake system while ensure braking reliability and fuel economy when the ABS is triggered, a novel switching compensation control strategy using sliding mode control is brought forward. The proposed strategy converts the complex coupling braking process into independent control of hydraulic braking and regenerative braking, through which a balance between braking performance, braking reliability, braking safety and fuel economy is achieved. Simulation results show that the proposed strategy is effective and adaptable in different road conditions while the large wheel slip rate is triggered during a regenerative braking course. The research provides a new possibility of low-cost equipment and better control performance for the regenerative braking in the EV and the hybrid EV.     

基于模糊控制方法的防抱控制系统的研究

本文采用模糊控制方法对车辆防抱制动系统进行了模拟研究，采用单轮的车辆模拟模型，用两种方法研究了防抱系统，即基于车轮滑移率的连续控制系统和基于车轮加减速度及参考滑移率的非连续控制系统。     

汽车防抱死制动系统H_∞控制与PID控制的比较研究

控制方法是汽车防抱死制动系统的核心技术。为了提高ABS系统的鲁棒性能,在建立汽车防抱死制动系统数学模型的基础上,设计了H∞控制器,在Matlab/Simulink平台上对基于H∞控制器的ABS系统进行了动态仿真,并与基于传统PID控制器的ABS系统进行对比。通过对仿真结果进行比较发现,PID控制和H∞控制都能使ABS系统获得较好的制动性能;H∞控制响应迅速、具有优秀的稳定性和鲁棒性,总体控制效果优于PID控制。     

防抱制动系统控制算法的仿真研究

本文用要平面法分析了目前汽车上广泛使用的Ｐ１Ｒ３逻辑控制算法在不同条件下的收敛性，因这种算法只能使车轮的滑移率在μ－Ｓ曲线的峰值点变化，故采用逻辑控制的ＡＢＳ系统不能充分发挥它的最佳效能，本文进一步通过仿真研究了基于滑移率Ｓ的控制算法，并根据逻辑控制和滑移率控制的缺陷，提出了基于路面附着系数μ的控制算法，在理想状态下的证实了所提算法的有效性。     

基于MATLAB的ABS控制仿真研究

ABS是一种变工况、非线性的系统,且建模难度大。分别采用PID控制、模糊PID控制两种方法对单轮汽车模型进行了模拟仿真。其中模糊PID控制可以利用模糊控制规则对PID参数进行在线修改,因而具有较好的自适应能力,可以达到非常好的控制效果。     

奔驰轿车的行驶稳定性电子控制系统

电子稳定程序（ＥＳＰ）控制系统是一种在各种行驶条件下能提高车辆行驶稳定性的主动安全体系。ＥＳＰ控制模块根据输入信号确定在当前行驶条件下，以下６种工作模式中的一些应被接通，即普通模式、ＡＢＳ控制模式、ＡＳＲ控制模式、ＭＳＲ控制模式、ＥＳＰ控制模式及ＥＳＰ切断模式。     

Emergency Braking Control with an Observer-based Dynamic Tire/Road Friction Model and Wheel Angular Velocity Measurement

Summary A control scheme for emergency braking of vehicles is designed. The tire/road friction is described by a LuGre dynamic friction model. The control system output is the pressure in the master cylinder of the brake system. The controller utilizes estimated states for a feedback control law that achieves a near maximum deceleration. The state observer is designed using linear matrix inequality (LMI) techniques. The analysis shows that using the wheel angular speed information exclusively is not sufficient to rapidly estimate the velocity and relative velocity, due to the fact that the dynamical system is almost unobservable with this measurement as output. Findings are confirmed by simulation results that show that the estimated vehicle velocity and relative velocity converge slowly to their true values, even though the internal friction state and friction parameters converge quickly. The proposed control system has two main advantages when compared with an antilock braking system (ABS): (1) it produces a source of a priori information regarding safe spacing between vehicles that can be used to increase safety levels in the highway; and (2) it achieves a near optimal braking strategy with less chattering.     

Emergency Braking Control with an Observer-based Dynamic Tire/Road Friction Model and Wheel Angular Velocity Measurement

Summary A control scheme for emergency braking of vehicles is designed. The tire/road friction is described by a LuGre dynamic friction model. The control system output is the pressure in the master cylinder of the brake system. The controller utilizes estimated states for a feedback control law that achieves a near maximum deceleration. The state observer is designed using linear matrix inequality (LMI) techniques. The analysis shows that using the wheel angular speed information exclusively is not sufficient to rapidly estimate the velocity and relative velocity, due to the fact that the dynamical system is almost unobservable with this measurement as output. Findings are confirmed by simulation results that show that the estimated vehicle velocity and relative velocity converge slowly to their true values, even though the internal friction state and friction parameters converge quickly. The proposed control system has two main advantages when compared with an antilock braking system (ABS): (1) it produces a source of a priori information regarding safe spacing between vehicles that can be used to increase safety levels in the highway; and (2) it achieves a near optimal braking strategy with less chattering.     

基于滑移率和减速度的ABS模糊控制仿真研究

在ABS逻辑门限值控制方法的基础上,通过分析道路试验数据,利用M atlab的模糊工具箱建立了模糊控制系统,采用7自由度整车模型在S imu link中进行仿真计算。仿真结果表明,基于滑移率和减速度的ABS模糊控制比逻辑门限值方法具有更好的自适应性,并可减少道路试验的工作量。     

48V轻混车型发动机与电机控制优化性能提升

对目前常见的汽车混合动力系统进行了简介。描述了一种48V混合动力车型开发过程中通过优化改善发动机与BSG电机的控制,在怠速(或低速行驶)且大功率用电工况、ABS工况以及急加速工况下存在问题的解决。为达到预期的设计效果及性能目标,需注重发动机控制系统与BSG电机控制系统的协同匹配。对于后续深度混合动力系统的开发具有很好的积累及推进作用。     

A Versatile Flat Track Tire Testing Machine

Summary A flat track tire testing machine developed by the IMMa group is described. It permits the simulation and study of the dynamic behavior of a great variety of tires under controllable and repetitive highly dynamic realistic working conditions in the laboratory for a diversity of vehicles, from motorcycles to light trucks. The machine incorporates: – a hydraulically operated tire support and loading system with wide operating ranges; – a computer controlled brake system to simulate braking maneuvers with ABS systems; – a complete sensorial system; – a data acquisition and control system continually monitoring and acting on the experimental variables, i.e., tire and belt speed, longitudinal slip, slip and camber angles, tire pressure, tire normal force, etc. As an application example, results are presented that adjust the parameter of the magic formula for a standard 175/70 R14 passenger vehicle tire. Accurate mathematical tire models are recognized as essential for the prediction of vehicle dynamic performances using simulation tools.