Intelligent Simulation System Of Auto Engine Signals

With the growing market of Chinese automobile, the independent research and development of Chinese automobile is more and more important. The core of independent R&D is automotive engine and its electronic control unit (ECU).The automotive engine ECU is responsible for the control of automotive engine combustion and emission etc. As the development and testing of engine ECU, engine is often required to run in the limit, as the situation of High-speed or flying car, for ECU's testing. The traditional approach which develop and test ECU with a real engine is dangerous, neither economic nor convenient. So now in the lab, the development and testing of engine ECU often use the simulation platform of engine signals to simulate the true engine. In traditional simulation platforms of engine signal, some signal generators piece together simply. They temper signals manually, the operation is complex and the platform can't simulate the true condition. The ancient simulation platforms often have low hardware and software; they can't satisfy the need of real-time control. The advanced simulation platforms are almost foreign products, such as Motorola and Bosch's products. However, foreign automotive electronic products protect the technology; they have dearly price, high maintenance costs and not timely services. They are usually custom-built and can't simulate other kind of engine. It dose harm to the development of ECU of our country. So, for the domestic automotive manufacturers, it's very important to develop an intelligent simulation platform of engine signal. And it's significant to debug the hardware and software of ECU.In this paper, aim to the development and testing requirements of some varieties of automotive engine ECU, it opens up an automotive electronic intelligent tool which called'Intelligent Simulation System of Auto Engine Signals'. It discusses in detail about the design of the system's hardware and software.According to system requirements, the system is divided into two parts: Lower machine and PC. And Lower machine is divided into five modules: Timing signal module, Analog and switch module, Power module, Front panel module and Rear panel module.The main MCU of Timing signal module is STM32F103VB, it responsible for generating electromagnetic crankshaft and camshaft signals, hall-style crankshaft and camshaft signals, knock signals. It has an UART communication interface to communicate with Analog and switch module, an USB communication interface to communicate Lower machine with PC , an external EEPROM for storing the basic information. It also controls digital tubes and LED which belong to it.The main MCU of Analog and switch module is dsPIC30F6014A, it responsible for generating analog signals, switch signals and frequency signals. It has two CAN communication interfaces and a K-LINE communication interface to communication with ECU, an UART communication interface to communicate with Timing signal module. It also controls digital tubes and LED which belong to it.System's power is an universal switching DC Power, the ECU's power is a precision DC power which can adjust the output voltage. The system and the ECU do not use the same power to ensure that there is no interference between system's power and ECU's power. It also Improves system's stability and reliability.Front panel is a display and control panel, responsible for displaying and adjusting the various signals.Rear panel is an interface panel, responsible for installing all kinds of sockets. ECU or other modules can be connected with sockets expediently to transfer diversified signals of system. PC is designed with LABVIEW, it can display and control all signals, save all data, configure timing-relation, and display status of different ECU with different agreements of CAN communication.The method of system software's design is modularization. Software modules and hardware modules are homologous, and the program uses C language. Program has good readability and can be explanted easily. It can shorten periods of exploitation and enhance work efficiency enormously. There is some software anti-jamming design in program. They can tone up stability and reliability of system.Besides basal engine signals such as hall-style crankshaft and camshaft signals, analog and switch signals, system can also generate electromagnetic and camshaft signals, associate camshaft signals with crankshaft signals, regulate relative location of camshaft signals and generate knock signals. The most important function is that it brings forward an intelligent method to configure timing-relation of auto engine. It can change the timing-relation expediently and simulate different engines.The method and experience of system are coming into use in'Common Rail Diesel Engine ECU Assistant Debug System'and'CNG Assistant Debug System'. At the same time, this system has steady functions and convenient operation. It is propitious to auto producer to use, it offers an reliable instrument to open out many engine ECU and it also offers a new method and thinking to open out simulation platforms of engine signals.