Background:
All the time, the safety of the vehicle has been valued by all the world's parties, whether it is now or in
the future, the automobile safety issue is the hotspot and focus of the research by experts and scholars. The continuous
increase of car ownership brings convenience to people's life and also poses a threat to people's life and property
security. Vehicle active safety system is the hotspot of current research and development, which plays an important role
in automobile safety. Firstly, the vehicle active safety technology and its development situation was introduced, then
Ref. review was carried out about Anti-Lock Brake System (ABS), Electronic Brake force Distribution (EBD/CBC),
Brake Assist System (BAS/EBA/BA), Traction Control System (TCS/ASR), Vehicle Stability Control (VSC/ESP/DSC),
etc. At present, there are many patents on the control of each subsystem, but few patents on the integrated control for
the active safety of vehicles.
Objective:
The main contents of this paper are as follows: the control strategies and methods of different active
safety systems, how to improve the stability of vehicle control and ensure the effectiveness of active safety system
control. It provides a reference for the development of active safety control technology and patent.
Methods:
Through the analysis of different control algorithms and control strategies of Anti-lock and braking force
distribution systems, it is pointed out that the switching of EBD/ABS coordinated control strategy according to slip rate
can make full use of slip rate and road adhesion coefficient to improve the safety of the system. For the BAS, the slip
problem is solved through the combination of Mechanical Assistant Braking System (MABS) and Electronic Braking
Assistant (EBA) system by measuring the distance of the vehicle ahead and the speed of the vehicle ahead. The optimal
slip rate control is realized by different control algorithms and control strategies of traction control system. It is pointed
out that the adaptive fuzzy neural controller should be used to control the yaw angular velocity and centroid side angle
of Electronic Stability Program (ESP), which has a good effect on maintaining vehicle stability. A sliding mode variable
structure controller combined with constant speed control and approach law control is used to control the yaw moment.
Results:
Through the coordinated control strategy of EBD/ABS, the slip rate and road adhesion coefficient were fully
utilized by switching according to slip rate. The problem of sliding slope is solved by MABS with EBA system. The
ESP should use adaptive fuzzy neural controller to control the yaw angular velocity and centroid side angle, and adopt
the joint sliding mode variable structure controller which combines the ABS control and the yaw moment control.
Through the optimal control theory, the coordinated control of each subsystem can significantly improve the driving
stability, riding comfort, fuel economy and so on.
Conclusion:
This adopt different control strategy and control algorithm for different active safety control system and
make full use of tire-road friction coefficient and slip ratio optimal slip ratio, then it realized accurate control of control
variables such as yawing angular velocity, centroid side-slip angle, yawing moment and finally ensure the vehicle
braking stability, robustness of the controller and the lateral stability of vehicle.
Electronic Differential System Based on Adaptive SMC Combined with QP for 4WID Electric Vehicles
