汽车安全气囊应用研究

论文编号:JD937   论文字数:23973,页数:57

摘  要
    汽车安全气囊作为一种辅助的乘员约束条件，在汽车发生碰撞时保护乘员的效用已越来越得到肯定，当今社会对安全气囊的要求也越来越高，尤其是对智能安全气囊的需求也越来越广泛，当汽车发生碰撞时汽车与汽车或汽车障碍物之间的碰撞称为第一次碰撞，第一次碰撞导致了汽车速度的急剧变化。由于惯性的作用，车上的乘员向前运动，于是发生了车内乘员与车内结构件之间的第二次碰撞，事故中造成乘员伤害的主要原因就是第二次碰撞。为了减轻和避免驾乘人员在第二次碰撞中受到伤害，乘员保护系统的设计目标是在碰撞中利用约束系统（包括座椅、安全带、安全气囊等）避免或减缓乘员与车内结构件碰撞造成的伤害。汽车安全气囊的基本思想是：在发生第一次碰撞后，第二次碰撞前，迅速在乘员和汽车内部构件之间插入一个充满气体的气囊，让乘员“扑”在气囊上，通过气囊上的排气节流阻力吸收乘员的动能，使猛烈的第二次碰撞得以减缓，以达到保护乘员的目的。所以安全气囊作为一种防护措施已经是必不可少了。我在此设计中主要进行了安全气囊的设计工作，对安全气囊的工作过程进行研究，为使乘员安全而设计一个合适的安全气囊。
 介绍自行研制的智能式汽车安全气袋控制系统，该系统主要由单片机、传感器、点火电路等组成，使用点火控制算法对汽车加速度信号进行判断，输出点火脉冲。本系统具有体积小、可靠性高、抗干扰能力强、可进行自诊断等特点。
 故设计的主要工作是对气囊电路中的CPU、加速度传感器的选择、继电器的选择及与电路有关的器件，如为防止错点火而要设计一个点火电路、为防止信号干扰我们要加光隔离等一些措施。所以我设计所做的主要工作就是对安全气囊的硬件电路实行操作并对其的工作原理进行分析，对其应用进行研究。
关键词：智能型安全气囊、防护、安全传感器、汽车碰撞。

 Abstract
      The auto safety aerocyst took one kind of auxiliary crew memberrestrains the condition，Has the collision when the automobile protects crew member''seffectiveness more and more to obtain the affirmation，Now the society also more and more is high to the security aerocystrequest。Also more and more is in particular widespread to the intelligentsecurity aerocyst demand，When the automobile has the collision the automobile and theautomobile or between the automobile obstacle collision is called thefirst collision，The first collision has caused the automobile speed rapid change。As a result of inertia function，On vehicle crew member to front movement，Thereupon has had in the vehicle in the crew member and the vehiclebetween the structural element second collision，In the accident creates the main reason which the crew member injures is the second collision。In order to reduce and avoids harnessing while the personnel receivesthe injury in the second collision，The crew protective system design goal is avoids or slows down the injury in the collision using the restraint system which in the crewmember and the vehicle the structural element collision creates。The auto safety aerocyst basic thought is：After has the first collision，Before second collision，Rapidly inserts in the crew member and between the automobile interior component to fill the gas the aerocyst，Let the crew member "throw oneself" on the aerocyst, absorbs crewmember''s kinetic energy through the aerocyst on exhaust throttleresistance, enables the violent second collision to slow down,achieved protects crew member''s goal. Therefore the security aerocyst
took one kind of protective measure already was essential. I havemainly carried on the security aerocyst design work in this design,conducts the research to the security aerocyst work process, forcauses the crew member safety to design an appropriate securityaerocyst。
 The introduction independently develops the intelligent type autosafety air pocket control system, this system mainly by the monolithicintegrated circuit, the sensor, the electric firing circuit and so onis composed, the use ignition control algorithm carries on thejudgement to the automobile acceleration signal, the output ignitionpulse. This system has the volume slightly, the reliability high, theantijamming ability is strong, may carry on from characteristic and so
on diagnosis。
 Therefore designs the main work is to in aerocyst electric circuitCPU, the acceleration instrument choice, the relay choice and the andcircuit related component, like for prevents the wrong ignition but tohave to design a electric firing circuit, for prevented the meaconingwe must add the light isolation and so on some measures. Therefore Idesign the main work which does am to the security aerocyst hardwareelectric circuit implementation operation and to its principle of workcarry on the analysis, conducts the research to its application.

Key word: Intelligence security aerocyst,；protection；security sensor； automobile collision.
 
 
目录
摘  要 I
Abstract II
第一章 绪论 1
第二章 安全气囊简介 3
2.1 安全气囊的作用与分类 3
2.1.1 安全气囊的作用 3
2.1.2 安全气囊的分类 3
2.2 安全气囊系统的组成： 3
2.3 安全气囊的工作原理： 5
2.4 安全气囊的工作过程 6
2.5 使用安全气囊注意事项 7
2.5.1 安全操作规范： 7
2.5.2 启爆后安全气囊的处理： 8
2.5.3 安全气囊的拆卸： 8
2.5.4 安全气囊的安装： 9
第三章 CAN总线在汽车内部的网络研究 10
3.1 CAN简介： 10
3.1.1 CAN 总线的概念 10
3.1.2 CAN 总线的特点 11
3.2 CAN总线的结构特点 13
3.2.1 CAN节点概述 13
3.2.2 CAN总线的分层结构 14
3.2.3 CAN总线的位数值表示 15
3.2.4 CAN总线的通信距离 15
3.3 CAN报文的帧格式 16
3.4 CAN总线高层协议介绍 20
3.5 CAN总线在汽车内的应用 23
3.5.1 汽车内部CAN网络设计 23
第四章 汽车安全气囊电路设计 26
4.1 控制系统的设计 26
4.1.1 气袋控制系统的要求 26
4.1.2 控制系统总体方案 26
4.2 控制系统硬件 27
4.2.1 总体方案 28
4.3 器件的选择 29
4.3.1 CPU及CAN收发器件的选择 29
4.3.2 加速度传感器的选择 36
4.3.3 电源 42
4.3.4 点火电路及气袋检测电路 43
第五章 论文结论 50