Anti-lock Braking System Control Research Articles

A study on an anti-lock braking system controller and rear-wheel controller to enhance vehicle lateral stability

This paper presents a mathematical vehicle model that is designed to analyse and improve the dynamic performance of a vehicle. A wheel slip controller for anti-lock braking system (ABS) brakes is formulated using a sliding mode controller and a proportional-integral-derivative (PID) controller for rear wheel steering is also designed to enhance the stability, steerability, and driveability of the vehicle during transient manoeuvres. The braking and steering performances of controllers are evaluated for various driving conditions, such as straight and J-turn manoeuvres. The simulation results show that the proposed full car model is sufficient to predict vehicle responses accurately. The developed ABS reduces the stopping distance and increases the longitudinal and lateral stability of both two-and four-wheel steering vehicles. The results also demonstrate that the use of a rear wheel controller as a yaw motion controller can increase its lateral stability and reduce the slip angle at high speeds.

Hierarchical intelligent control of automobile anti-lock braking system

A new method using difference of the peak values of wheel velocity to calculate reference vehicle velocity and ref- erence slip ratio is proposed,which is based on the analyses of the mechanics characteristics between the tire and the road when the vehicle is being braked.To solve complex control problem of automobile anti-lock braking system(ABS)in dif- ferent conditions,a hierarchical intelligent control(HIC)system is investigated.It includes running control level,parameters adjusting level and organization coordination level.According to the instantaneous performance index of reference slip ratio,a human-simulation intelligent controller(HSIC)aiming at con- trolling reference slip ratio is designed in running control level. The characteristic model,control modes set and reasoning rules set are built.In parameter adjusting level,to decrease the deft- ciency of reference slip ratio control,a method is pointed that modifies the calculation values of HSIC pursuant to wheel an- gle deceleration.In coordination level,a fuzzy intelligent con- troller with the inputs of wheel deceleration and reference slip ratio is designed to implement road automatic identification. Then four wheels braking coordination control rules are also given.The simulation on HIC system of ABS is developed with Matlab.An automotive ABS test and control system is con- structed and the road tests under different conditions are com- pleted according to the international standards.Compared to traditional logic gate control,test results show that the HIC is an effective new ABS control method with better braking sta- bility,adaptiviness and control accuracy.

차량의 선회시 주행 안정성 강화를 위한 ESP 시스템 개발 및 성능 평가 (II)

Two yaw motion control systems that improve a vehicle lateral stability are proposed in this study: a rear wheel steering yaw motion controller (SESP) and an enhanced rear wheel steering yaw motion controller (ESESP). A SESP controls the rear wheels, while an ESESP steers the rear wheels and front outer wheel to allow the yaw rate to track the reference yaw rate. A 15 degree-of-freedom vehicle model, simplified steering system model, and driver model are used to evaluate the proposed SESP and ESESP. A robust antilock braking system (ABS) controller is also designed and developed. The performance of the SESP and ESESP are evaluated under various road conditions and driving inputs. They reduce the slip angle when braking and steering inputs are applied simultaneously, thereby increasing the controllability and stability of the vehicle on slippery roads.

Anti-Lock Braking Control of a Hybrid Brake-By-Wire System

This paper presents a non-linear sliding mode type controller for slip regulation in a braking event for a hybrid electromagnetic-electrohydraulic brake-by-wire (BBW) system. The anti-lock braking system (ABS) controller modifies the brake torque command generated by a supervisory controller based on a driver request via the brake pedal sensor. The brake torque command is then generated by a closed-loop actuator control algorithm to control the eddy current brake (ECB) and electrohydraulic brake (EHB) systems. The proposed control algorithm shows very good slip regulation in a braking event on low friction coefficient surfaces when compared with non-ABS braking. It has been observed that the eddy current brake provided most of the torque while the electrohydraulic brake compensated for the difference between ABS torque command and estimated ECB torque. The result is a very smooth ABS stop minimizing the noise, vibration, and harshness (NVH) of current hydraulic ABS systems. It is also shown that the closed-loop system is stable in the sense of Lyapunov stability theory.

Implementation of a PC-based ABS system with CAN-bus interface on an experimental platform

An experimental platform is constructed to test a designed CAN (Controller Area Network) interface of an ABS (Anti-lock Brake System). A PC-based ABS ECU with CAN interfaces is designed and implemented for testing. Four wheel speed signals and one brake pedal switch signal are sent to the CAN via the designed input interfaces. Through the CAN interfaces, on/off commands from the controller can drive the eight solenoid valves and a pump motor. Accordingly, all of the signals can be transmitted through the CAN bus in the ABS control system loop. Using the developed CAN I/O interfaces, a PC with a CAN interface card can receive the inputs and send out control signals to the ABS module. The developed circuits are experimentally verified in the platform. The proposed system incorporates a CAN bus configuration to reduce the complexity of the interconnections among ABS components.

Future Vehicle Driven by Electricity and Control—Research on Four-Wheel-Motored “UOT Electric March II”

The electric vehicle (EV) is the most exciting object to apply motion technique. As an EV is driven by electric motors, it has the following three remarkable advantages: 1) motor torque generation is fast and accurate; 2) motors can be installed in two or four wheels; and 3) motor torque can be known precisely. These advantages enable us to easily realize: 1) high performance antilock braking system and traction control system with minor feedback control at each wheel; 2) chassis motion control like direct yaw control; and 3) estimation of road surface condition. UOT Electric March II is our novel experimental EV with four in-wheel motors. This EV is made for intensive study of advanced motion control of an EV.

Development of fuzzy controlled ABS systems for motorcycles

In this paper, we present the design and implementation of a new mechanism for an antilock brake system (ABS) pressure regulator on motorcycles. We use static tests to ensure the pressure regulation function. The dynamic test is constructed in the experimental bench for the closed-loop motorcycle ABS control. Furthermore, two fuzzy controllers are designed and tested in the platform (respectively). The first one directly uses the slip ratio error and its change as two inputs to the controller. However, in most implementations, the slip ratio is not available. Thus, the other controller that uses wheel speed and its change rate as inputs is also used in the experiments. The performances of these two control systems are verified in the platform. Both controllers can achieve their goal of tracking the desired slip ratio.

The rapid development of a vehicle electronic control system and its application to an antilock braking system based on hardware-in-the-loop simulation

The paper describes in detail a rapid development system for vehicle electronic control systems by using real-time hardware-in-the-loop (HiL) simulation technology. This system can be used in parallel with the development of a new vehicle electronic control product. Once desired simulation results are achieved from the real-time HiL simulator in laboratory environments, control system design can be verified by setting up the same configuration in the new product in-vehicle test. The correlation between HiL simulation results and vehicle field test data can thereby be evaluated. The feasibility and effectiveness of the rapid development system have been demonstrated through the development of a vehicle antilock braking system (ABS) control algorithm. A significant reduction in development cycle time and cost has been achieved with the aid of this powerful tool, and the effectiveness of the ABS algorithm has been validated in vehicle field tests. The proposed ideal and approach can also be applied to develop other control systems, such as a traction control system, a vehicle stability control system, etc.

Braking performance simulation for a tractor-semitrailer vehicle with an air brake system

Recently safety systems for commercial vehicles have been developed rapidly. However, there are still many problems in the vehicle stability and the braking performance. In particular, a commercial vehicle may meet a dangerous braking condition when the vehicle is lightly loaded or empty and when the road is wet or slippery. Under these conditions, the truck can spin out, the tractor can jackknife or the trailer can swing out. To design an air brake system for a commercial vehicle, since the air brake system has many design variables, there must be intense research on a method on how to prevent dynamic instability and how to maximize vehicle deceleration. In this study, mathematical models of the tractor-semitrailer and the air brake system including an antilock brake system controller have been constructed for computer simulation. Also, simcopy IMple examples are applied to show the usefulness of the program. Designers can use this simulation program for understanding the braking characteristics such as trajectory, braking distance, longitudinal deceleration, lateral deceleration and yaw rate under various braking conditions.

Anti-lock brake system control for buses based on fuzzy logic and a sliding-mode observer

In this paper, an anti-lock brake system (ABS) for commercial buses is proposed based on a fuzzy-logic controller and a sliding-mode observer of the vehicle speed. The brake controller generates pulse width modulated (PWM) control inputs to the solenoid valve of each brake, as a function of the estimated wheel slip ratio. PWM control inputs at the brakes significantly reduce chattering in the brake system compared with conventional on-off control inputs. The sliding-mode observer estimates the vehicle speed with measurements of wheel speed, which is then used to compute the wheel slip ratio. The effectiveness of the proposed control algorithm is validated by a series of computer simulations of bus driving, where the 14-DOF bus model is used.

Integrated chassis control system to enhance vehicle stability

Vehicle stability enhancement system, by controlling vehicle dynamics, is the latest active safety technology introduced since Antilock Brake System (ABS) and Traction Control System (TCS). This system provides the driver with enhanced vehicle stability and handling. It is the intent of this paper to provide an understanding of the fundamentals of control of vehicle stability. The paper describes a complete stability control algorithm. Starting with a model for the vehicle yaw-plane dynamics, we derive a desired vehicle response, using both time-domain and frequency-domain approaches. Control structures include both yaw rate feedback design, and full-state feedback design. The latter approach requires the estimation of vehicle side-slip velocity. Estimations based on integration of lateral acceleration, the use of algebraic equation using vehicle kinematics, and the use of a Luenberger observer are presented. Computation of the required wheel differential velocity to achieve control objectives is described. Finally, computer simulation is used to investigate and confirm the concepts being discussed.

Analysis and redesign of an antilock brake system controller

Antilock braking (ABS) systems are a combination of hydromechanical braking components with switching solenoids and relays which operate the brakes in response to wheel and vehicle speed information. The control law which calculates the braking is a complex set of logical rules designed to allow for variations in road conditions and the nonlinear nature of tyre friction characteristics. The piecewise linear action of the actuator components (solenoids and relays) and the logical control rules make it difficult to analyse the dynamical behaviour of an ABS using conventional methods. The paper describes the analysis and subsequent redesign of an ABS using a new method for studying the dynamical behaviour of piecewise linear systems. The method is applied to a conventionally designed ABS controller. Undesirable performance features, not evident from conventional simulation and testing procedure, are found and the controller is redesigned to give a satisfactory dynamical performance.

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.