汽车ABS系统优化及关键技术研究

发布时间：2018-03-11 08:45

本文选题：ABS系统　切入点：滑模控制　出处：《江西理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着汽车时代的发展,汽车与人们联系越来越紧密,成了人民大众最常用的交通工具。因此,中国消费者不仅仅对汽车的数量有着很大的需求,对汽车的安全驾驶性能,尤其是ABS系统的安全性要求越来越高。ABS系统虽然还不能保证汽车达到完美控制状态,但它大大的提升了汽车制动过程中的安全性和稳定性。如今ABS系统成为了一般乘用车的标准配置,科技的进步、电子产业的飞速发展、电子产品的推陈出新也为ABS系统技术提供了广发的发展空间。目前,市场上存在的ABS系统基本分为机械式与电子式两大类。机械式ABS系统结构简单使用方便,主要安装在一些皮卡和低档配置的客车上,它的主要结构是一个机械阀,在工作过程中系统通过阀体内的橡胶气囊对刹车压力进行检测,然后根据刹车压力的大小对车轮进行循环的放松、制动,从而达到防止抱死的效果。电子式ABS系统相对于机械式而言结构较为复杂体积更小,主要构成部件构成为轮速传感器、导线、CPU、制动器、指示灯等,在电子式ABS系统工作过程中,首先由各个传感器向CUP发送测量号,然后由CPU根据传感器测量的信号按一定算法处理后向ABS控制器发出控制信号,控制发动机扭力输出。由于电子式ABS系统可以根据不同的情况向各个车轮发出强弱不同的信号从而施加不同的刹车力度,因此电子式ABS系统能够更加合理的分配制动力,极大地减少了紧急状态下车辆跑偏、侧滑、甩尾现象,从而达到了防患于未然的目的。然而,目前的汽车ABS系统在对汽车刹车过程中的滑移控制、在不同工况下的自适应能力等方面还有待改进,同时,汽车ABS系统的系统性能没有最好,只有更好,研究改进性能更好的ABS系统也是业界一直在努力的课题。本文主要在总结前人工作的基础上,结合汽车动力学,以控制滑移率为目标,对汽车ABS系统控制技术进行优化研究。由于汽车ABS系统是一个时变非线性系统,而滑模控制对系统存在的不确定性因素和外界干扰因素具有优良的抗干扰性能,所以在建立ABS动力学系统模型(包括汽车动力学模型、轮胎模型、控制器模型、电机模型以及制动器模型等)的基础上将滑模控制引入所建立的汽车ABS动力学系统模型中,并采用饱和函数法消除抖振现象。此外,针对防抱死制动系统研究中存在的最佳滑移率寻优等关键问题,本文采用的基于LuGre模型的离线计算方法能够很好的解决问题。最后利用神经网络算法,结合滑模控制方法进一步设计了智能滑模控制器。在MATLAB上对基于固定滑移率以及最优滑移率的ABS系统进行了仿真,仿真果表明,与普通滑模控制器相比,所设计的智能滑模控制器性能更加优越,控制效果更好。
[Abstract]:With the development of automobile age, cars are more and more closely connected with people and become the most commonly used means of transportation. Therefore, Chinese consumers not only have a great demand for the number of cars, but also have a great demand for their safe driving performance. Especially, the security requirement of ABS system is getting higher and higher. But it has greatly improved the safety and stability of automobile braking process. Nowadays, ABS system has become the standard configuration of passenger cars, the progress of science and technology, and the rapid development of electronic industry. The emergence of new electronic products also provides a broad development space for ABS system technology. At present, the existing ABS systems in the market are basically divided into two categories: mechanical and electronic. The structure of mechanical ABS system is simple and easy to use. Mainly installed on some pick-up trucks and low-grade passenger cars, its main structure is a mechanical valve, in the course of work, the brake pressure is detected through rubber airbags in the valve body. Then according to the size of brake pressure, the wheel is circularly relaxed and brake, so as to achieve the effect of preventing locking. The electronic ABS system has a smaller complex structure than the mechanical one, and the main component is the wheel speed sensor. In the working process of electronic ABS system, each sensor sends the measurement number to the CUP, and then the CPU processes the signal according to the signal measured by the sensor according to a certain algorithm and then sends out the control signal to the ABS controller. Control engine torque output. Because electronic ABS system can send different signals to each wheel according to different conditions and apply different braking force, electronic ABS system can distribute braking force more reasonably. The phenomenon of vehicle deviation, side slide and tail-flick is greatly reduced during the emergency. However, the current vehicle ABS system controls the slippage in the braking process of the vehicle. At the same time, the system performance of automobile ABS system is not the best, only better. The research of improving the ABS system with better performance is also a subject that the industry has been working on all the time. On the basis of summarizing the previous work and combining with the automobile dynamics, the aim of this paper is to control the slip ratio. The control technology of automobile ABS system is optimized. Because the automobile ABS system is a time-varying nonlinear system, the sliding mode control has excellent anti-interference performance to the uncertainty and external disturbance factors of the system. Therefore, the sliding mode control is introduced into the vehicle ABS dynamic system model based on the ABS dynamic system model (including automobile dynamics model, tire model, controller model, motor model and brake model, etc.). The saturation function method is used to eliminate the chattering phenomenon. In addition, the key problems in the study of anti-lock braking system, such as the optimization of the optimum slip ratio, are discussed. The off-line calculation method based on LuGre model can solve the problem well. Finally, the neural network algorithm is used to solve the problem. The intelligent sliding mode controller is further designed with the sliding mode control method. The ABS system based on the fixed slip ratio and the optimal slip ratio is simulated on MATLAB. The simulation results show that, compared with the ordinary sliding mode controller, The designed intelligent sliding mode controller has better performance and better control effect.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U463.526

【参考文献】