摘 要
ABS系统可以显著提高或改善汽车紧急制动时的操控性和稳定性,缩短了制动距离,是一种新型的汽车电子控制产品,并得到了越来越广泛的应用。
本文以轿车为研究对象,展开对汽车ABS的研究。主要完成了以下的工作:
通过对单个车轮时的受力分析确定了影响车轮附着系数的主要因素;
通过比较电磁感应式轮速传感器和霍尔效应传感器的性能优缺点,采用并设计了霍尔效应式轮速传感器;
通过对控制结构的分析设计了以INTEL公司生产的80C196KC单片机为核心的实时控制系统,包括信号输入电路、控制输出电路、驱动电路等硬件部分;
经比较各种控制方案,确定了“逻辑门限制法”作为控制方案,并选用加速度和滑移率的组合作为控制参数。采用事件门限来计算车轮的转速。
本文通过学习比较根据所学只是设计了ABS控制系统。从理论上实现了ABS的控制功能,完成了设计要求。在设计过程中对汽车制动理论和制动装置有了较为深入的了解,扩大了自己的知识面,自己解决问题的能力也得到了提高。
关键词:防抱死制动系统 电子控制单元 门限值滑移率 轮速传感器
ABSTRCT
Anti-lock Braking System (ABS) is an important device to improve the active safety of vehicle. ABS can greatly improve steering control ability during the brake maneuver and shorten stopping distance. Today with the improvement of the vehicle speed, ABS is applied widely.
With the car as the research object, the research on ABS has been carried on. And a series of work were finished:
The dynamic situation of wheel was analyzed. Then, the model of hydraulic ABS was built and assured main complication affect the wheeler appendiculate coefficient.
By comparing the capability of electromagnetism rotate speed sensor with Houer rotate speed sensor, we chose the later, and have designed a sensor of this kind.
Via analyse the control system structure, we have designed a real-time system with the singlechip 80c196kc produced by Intel company .It comprises with signal input, singlechip system, output, drive electro circuit and otherwise parts of hardware segment.
After comparing the different projects of the controllers, the method of logic rate has been comfirmed, and the combination of acceleration and slippage rate as been chose as control parameters. The time gate method to calculate the wheel rotate speed was adopted.
In this paper, based on the knowledge I have mastered, I designed a ABS system and realized the control function in theory, accomplished my assignment. I have gotten a in-depth understand of motorcar trig theory and equipment. It widen my knowledge scope, improved my ability of solving problems.
Kyewords: ABS electronic control slippage gate rotate speed sensor
目 录
1.4 国内ABS系统研究的理论状态和具有代表的ABS产品公司 5