汽车发动机电控系统在线检测的研究

【作者】 杨婕；

【导师】 封维忠；

【作者基本信息】 南京林业大学 ， 森林经理学， 2005， 硕士

【摘要】 随着计算机技术和汽车工业的发展,汽车检测诊断技术也日益发展起来。本文针对汽车发动机这一特定研究对象,对汽车发动机的在线检测系统进行了研究和开发,自行设计了具有信号调理、数据采集等功能的硬件设备,并在可靠的硬件基础上开发了应用于计算机终端的软件系统。该系统在低成本的条件下,实现了相对的模块化,主要分为三个模块:模拟模块、数字模块以及PC 终端模块。本文从系统的需求着手,自上而下地进行了介绍:系统的整体结构及主要功能;各模块功能和具体实现;各模块之间的接口。　模拟模块上,为了减小干扰对信号的影响,在信号调理部分的设计中重点考虑了抗干扰设计,通过反复实验,设计出最佳的电路方案,既保证了模拟信号采集的线性度,又增强了抗干扰能力,提高了测试系统的可靠性。　数字模块的硬件设计从采集需求和一些关键指标着手,设计出较为简洁的数字电路。软件工具使用了Keil C 编程语言。该部分重点分析了数字模块与计算机的通信流程,定制出通信协议,以确保计算机终端在任何时刻都能和数字板进行通信,且不影响双方其他程序的运行。　PC 终端模块采用了虚拟仪器技术,使用LabVIEW 图形化编程语言,开发了具有实时数据采集、信号分析和处理,且有类似于传统仪器操作和显示等功能的软件系统。　最后,本文还给出了系统测试结果,对系统的优缺点进行了分析,并提出了改进方法。　这种针对汽车发动机而构建的检测诊断系统,经过实验证明,具有成本低、效率高、性能稳定的特点,且界面友好,使用方便,具有一定的实用价值。更多还原

【Abstract】 Following the development of the computer science and automotive industry, the technology of automobile detecting system is developing too. This dissertation aims at automobile engine this special object, designs and exploits the signal conditioning and data acquisition hardware. Based on this reliable hardware, exploits the software which applies to the computer. This system implements a relative blocking with low-cost. There are three blocks in this system: analog block、digital block and computer terminal block. The dissertation starts at the requirement of the whole system, introduced from above to below: the structure of the whole system and main functions; the function and the interface of each block. On analog block, it is very important to consider the anti-interference design to minish noise. The optimal circuit design is from a lot of experiments, so it can insure the linearity about the analog signal acquisition, buildup the anti-interference ability and enhance the detecting system reliability. The design of digital block starts with a lot of key index, in order to design a compact digital circuit. To customize a communication protocol, the communication flow analysis is needed, so the computer and the digital circuit can communicate all the time without disturbing the program running each other. On this part the Keil C programming language is used. Computer terminal block adopted the virtual instrument technology, used graphics mode programming language —LabVIEW, exploited an application on computer .This application have real-time data acquisition、signal analysis and disposal functions, can output as oscillograph mode. At last , the dissertation gave a result of this detecting system, analyzed the merits and demerits of the system and advised mend methods. The system has low-cost、high efficiency and reliable performance characters, and can be uses conveniently with friendly interface. A lot of experiments proved that this automobile engine detecting system has definite applied worthiness.更多还原