基于PIC 单片机的通用胎压监测系统的设计外文翻译完成版.doc

毕业设计(论文)外文资料翻译 系 别： 电子信息系 专 业： 通信工程 班 级： B090310 姓 名： 李 莎 学 号： B09031038 外文出处： 网络资源 附 件： 1. 原文； 2. 译文 2013年03月12原文：Design of Universal TPMS Based on PIC MCU1 IntroductionWith the high speed of road network booming rise，Traffic is developed，Vehicle speed increasing, traffic hazards prevention problems imminent, if because of the tire air-leaks and explosion etc cause traffic accident, many are by tyres work to high temperature or unreasonable tire pressure cause. Research car tires tire pressure monitoring system of modern automobile driving, when the economy, safety and manipulation stability is particularly important practical significance.Hardware constitution and software design method of the universal TPMS are introduced based on PIC MCU.The Design projects of the remote monitoring module based on infineon SPI2 sensor, Microchip rfPIC12F675F with ASK/FSK transmitter and the central receiver module based on Microchip PIC16F877A are described, and hardware circuitry and related programs flowcharts, communication protocols and algorithms are given1The system can measure the tires interior temperature, instantaneous pressure, voltage and acceleration at anytime, indicate the blooey tires and alarm the driver to avoid the danger.Its of great importance for the popularization and optimization of the TPMS in our country.As authoritative research indicates,the key to Prevent a tire blow-out is maintaining standard tire Pressure and detecting tire fault beforehand.Thus,tire Pressure monitoring becomes meaningful and important.TPMS ( Tire Pressure Monitoring System )，Mainly used in automobile driving real-time monitoring of tyre pressure automatically. Currently developed countries of the tire pressure early-warning system mainly divided into two types: one is JiaJieShi, it through car ABS (anti holding brake system) of the wheel sensor and tyre mechanical model, indirectly calculated for tyre pressure, in order to achieve the purpose; monitor tyre pressure Another kind is direct type, it USES installed in each of the tires with lithium ion battery for power supply pressure sensor to direct measurement of tyre pressure, and through wireless modulation launch to install in search of monitor, and monitor at any time display various tyre pressure, drivers can intuitivey understanding each tire pressure condition, when the tyre pressure is too low or have leakage, the system will automatically alarm, ensure safety.TPMS as a new type automobile active safety device has been developing rapidly in recent years worldwide. Since it could monitor tire pressure and temperature in real time and alert the driver in time, most traffic accidents caused by flat tire could be avoided to ensure safe driving. The development of tire pressure monitoring systems is reviewed including wheel speed based TPMS, pressure-sensor based TPMS and the coming generation so called non-battery passive TPMS. The components and working mechanism of tire pressure monitoring system are introduced and their merits and defects analyzed and compared with the emphasis on three dominant direct TPMS systems, which are significant in its research and development. The prospect of future development trend is looked ahead. The non-battery TPMS is expected to replace the current one and become the dominant.Wireless signal transmission stability reliability insufficiency, the battery life problem, sensor life and durability problem, is the present T PMS products in the common problem. This system in addition to the sensor, all use Microchip company transceiver chip and micro control processor, low energy consumption, good compatibility and high reliability.And utilize FSK modulator mode, one-way communication mode, improving the system of signal transmission of anti-interference ability. Combined with the system USES the SP12 sensor and monitoring module microprocessor rfPIC12F675F characteristics, adopt LF low-frequency sensei technology, time-sharing send and receive different monitoring module rf signals, thus solving signal collision interference problems, and further energy saving system.2 System RequirementsCause a flat tire and blowout reasons are as follows:tyre temperature is exorbitant, the tyre pressure too big, tyres used for a long time, tire overload, automobile driving too fast.For that car to be in a safe driving condition, drivers must in driving process real-time understand tyre overpressure, voltage, temperature, etc. Work of the state, the system has the following functions: real-time monitor tire pressure, temperature conditions, when a tire over-voltage, overheating, automatic sound and light alarm, when a tyre in undervoltage condition, corresponding the advantages indicator emit light.3 Hardware DesignThe system was divided into two Parts functionally:tire Pressure measuring block and central monitoring block.The haudware composition was introduced respectively;hardware circuits ofeach block were also presented in this paper.Performance and function of main chips were introduced in detail,such as the sensor SP12,rfPIC12F675(MCU with embedded UHF translmiter),receiver rfRXD0420,PIC16F877,and some other important components like LCM(with a T6963Ccontroller embeded)and ete.To enhance the anti-interference performance and realize low powerConsumption management,an active Low Frequency(LF)wake-up technology was adopted.As for software design,a dynamic time cycle measuring and transmitting method was proposed,and corresponding software arithmetic were given,Combining LF wake-up technology with low power management thought.Taking into consideration severe electromagnetic interference environment of cars,a CRC(Cyelic Redundancy Cheek)arithmetic was added into the communication protocol frames,compositive software filtering methods were also used to enhance the Reliability and preside of the system.This system consists of 5 modules, as shown in figure 1 shows, 4 for tyre within the surveillance modules, a used car, receiving modules. Monitoring module includes sensor and launch module. The sensor to measure the pressure and temperature signals are converted to electric signals through wireless transmitting devices will signal launched. The pressure of the temperature sensor launched by the receiving module can receive and process information,after driving on the display shows that in the course of driving real-time monitor. Showing the way such as LED, LCD or voice prompt, etc. Can be in accordance with the actualrequirements to design. The tyres monitoring module by central mainframe control module low-frequency LF signal control, settle into work patterns interval time-sharing, rest time dormant.3.1 Hardware design of the master control module Car tires unique working environment conditions determines the tire pressure real-time monitoring of the high pressure sensor objectives: wide temperature area, wide voltage range of high accuracy and reliability, Low power requirements; Bad environment wireless signal transmission stability requirement. This system USES Infineon (Infineon) company SP12 tyre pressure temperature acceleration special detection sensor.Because electricity saving and super small-scale demand, so adopted SP12 sensor. SP12 is a kind of piezoelectric resistor sensor, besides can measure pressure and temperature besides,still integrated add speed sensor and voltage preach implement, pressure measurement range 100 450kPa, temperature measurement range for - 40 + 125. The average power consumption for standby mode only 13 muon A. Has the SPI serial communication mouth, more convenient and controller can be composed SCM system.RfPIC12F675F Microchip company is launched monolithic integrated embedded rf wireless data transmitters 8-bit CMOS micro controller. 1024 x 14 programmable an EPROM, 64 x 8 bytes data storage, 128 x 8 bytes EEPROM data storage, 16 special function of hardware registers, The watchdog timer, low power consumption, sleep patterns, six general I/O functions; Working voltage, low power consumption 55V 25 sleep patterns for 500 mu A current. Embedded UHF add/FSK emitter, rf frequency range for 230 930MH z,adjustable output power + 6 - 15dBm, add data emission rate 0 40Kbps, FSK data launch rate 0 20Kbps; PLL phase-locked VCO, integrated oscillators, and that the circuit only a few external components. Comply with US and European EN300220 ts 15231 FCC rules.The tyres monitoring module circuit structure as figure shows, by micro controller rfPIC12F675F, pressure and temperature acceleration sensor SP12, antenna network and LF low-frequency awakening of circuit composed of four. Peripheral components and simple circuit, and high reliability. Using the SPI serial data interface SP12 SDO, SCLK and SDI respectively with micro-controller rfPIC12F675F on GP4, GP1 and GP2 connection, because rfPIC12F675F without hardware SPI function, but it is easier for software simulation and SP12 between serial communication. The built-in launch chips contain transmit power amplifier PA, the crystal oscillator, phase-locked VCO is PLL, VCO and pattern logic control blocks circuits, etc. This application system by working frequency for 433M Hz, XTAL pins and FSKOUT pins between join external crystal oscillator clamps its X1 capacitor C1, C2,realize FSK modulation. When DATAFSK=1, FSKOUT for high impedance condition,transmit frequency fMAX; for, When DATAFSK=0, FSKOUT and VSSRF grounding,capacitance C1, C2 in parallel, the transmit frequency for f MIN. This system transmission power for + 2dB, standby current consumption only 10 mu A. During liftoff, VCO output signal is directly into the VCO output to PA, the frequency of crystal oscillator frequency 32 times, taking landuse-dat AFSK the input of digital signal (GP0 for signal input control terminals, and taking landuse-dat AFSK connected) was FSK after power amplifier output,PA to direct drive antenna.The low-frequency sensei module by L and C form a parallel LC resonant circuit used to receive from the host a LF sensei signal. Output terminal with rfPIC12F675FIO port GP3 connected, as the result of a relatively high voltage, comparator output interrupts. Sensei rfPIC12F675F, the sensitivity of 5mV.3.2 Host control module hardware design The main engine control module by low frequency signals sent circuit and MCU, rf receive circuit and human-computer interface 4 parts. One chooses MICROCHIP companies producing the MCU midrange micro controller PIC16F877A, it has low price, high performance, chip rich resources and high reliability etc. Low frequency signal transmission circuit adopts high-power CMOS chip drive serial driver resonant circuit, sending low frequency signal. Rf receive circuit used MICROCHIP rf receiver chips r fRXD0420, it has small, receiving high sensitivity, strong anti-jamming capability advantages. The man-machine interface circuit using mature module design, use the buttons as input interface, 128 * 64-bit bitmap graphics LCD as output interface.When the circuit in-tune, tandem resonance frequency by formula: f = 1 / (2 L C). As to reduce cost, tandem resonant circuit driver PIC16F877A PWM signal used by its issued function, driven signal incentive series circuit.4 Software designTPMS system is strictly for power requirements, so they need good algorithms for complete system requirements.You should minimize the number of required for TPMS because of power-transmission system.The sensors need little of power consumption in sleep mode.4.1 Tire Monitoring Module The system goes into sleep mode after initialization, waiting for the host module LF low frequency signals emitted wake. Resolved and the LF signal based on the received command, configure the sensor SP12, real-time pressure and temperature data collection, taking the average 100 (false alarm), formed by the data frame transmitted encoded data. Start UHF RF transmitter circuit for data transmission.4.2 Host display moduleHost PIC16F877A after initialization (including the completion of its surrounding RF module and display module initialization), by scanning interval to four tire rotation frequency of 125kHz module sends an LF low frequency signals, in turn will activate and turn the tire module RF receiver interrupt waiting to receive each module sends back the tire temperature data in real time for the decoded analysis, the standard set safety pressure and temperature range, and determines whether the alarm, and transmit data to the liquid crystal screen display. Set reasonable time delay, the loop above flow timeshare acquisition and monitoring the pressure of the tire module temperature conditions. Thus the fundamental solution to the problem of collisions with the frequency signal interference, but also to save power provides an effective control methods. Fully into account the energy and real-time monitoring of these two factors, the system initiates a set interval 200ms LF wakeup operations.4.3 Communication ProtocolIn order to achieve four tire module and the central host to receive module for wireless communication, a communication protocol must be developed. Manchester encoding used here, FSK Modulation and 9600BP / S transfer rate. Tire module sends data in the form of data frames, when the tire module rfPIC12F675F determine when to send data, the leading bit of the data frame by sending a wake up the host receiver module then sends ID, pressure, temperature, status, parity, and stop bits.5 SummaryThis paper proposes a new method of calculating target distance.This method does not need to obtain accurate focusing of the image, you only need a normal CCD camera to get the distance information, so the system structure is simple, easy to operate .While using a single camer a from selecting and feature points for image registration, in favour of real-time system implementation;And the algorithm to take full advantage of all color information for the image, avoid using grayscale image information loss-free .Experiments show that its effect is better than using a grayscale image to obtain depth information.译文：基于PIC 单片机的通用胎压监测系统的设计1 引言随着高速公路网的蓬勃兴起，交通的日趋发达，车辆行驶速度的不断攀升，交通隐患的防范问题迫在眉睫，如因车胎漏气和爆炸等原因造成的交通事故，很多是由轮胎的工作温度过高或者不合理胎压引起的。研究汽车轮胎胎压监测系统，就对现代汽车行驶时的经济性、安全性和操纵稳定性具有尤为重要的现实意义。PIC单片机的轮胎压力通用监测系统的硬件组成及软件设计方法，阐述了基于英飞凌SP12传感器和带ASK/FSK调制发射芯片的rfPIC12F675F微控制器的轮胎监测模块设计方案和基于PIC16F877A单片机的中央主机接收模块的设计方案，并给出了模块硬件电路以及相关程序框图、通信协议和算法等；该系统可随时测定每个轮胎内部的实际温度、瞬压、加速度和传感器电压,确定故障轮胎并实时发出警告，有效避免事故的发生；该方案的提出有利于国内TPMS产品的普及和功能优化。 权威的研究结果表明，保持标准的轮胎气压和及时发现轮胎故障是防止爆胎的关键，这就使对轮胎充气压力实行监测显得非常重要。TPMS( Tire Pressure Monitoring System )，主要用于在汽车行驶时实时的对轮胎气压进行自动监测。目前各国研制的轮胎气压报警系统主要分为两种类型：一种是间接式，它通过汽车ABS( 防抱制动系统) 的轮速传感器及轮胎的力学模型，间接求出轮胎气压，以达到监视轮胎气压的目地；另一种是直接式，它利用安装在每一个轮胎里的以锂离子电池为电源的压力传感器来直接测量轮胎的气压，并通过无线调制发射到安装在驾驶台的监视器上，而监视器随时显示各种轮胎气压，驾驶者可以直观地了解各个轮胎的气压状况，当轮胎气压太低或有渗漏时，系统就会自动报警，确保行车安全。轮胎气压监测系统是汽车上一种新的主动安全技术产品，近年来，在国内外发展迅速。由于它能够实时监测汽车轮胎的气压和温度情况，并能及时给驾驶员以警告，因而可以最大限度地避免由爆胎引发的交通事故，提高了汽车的行车安全。综述了汽车轮胎气压监测系统的发展，包括间接式轮胎气压监测系统、直接式轮胎气压监测系统和下一代无电池轮胎气压监测系统(被动式TPMS)。展望了未来轮胎气压监测技术的发展趋势：无电池TPMS将取代现有类型，成为未来TPMS发展的主流。 无线信号传输的稳定性可靠性不足、电池寿命问题、传感器寿命和耐久性等问题，是目前T PMS产品中普遍存在的问题。本系统除传感器外，均采用Microchip公司的收发芯片及微控制处理器，能耗低，兼容性好，可靠性高。并采用FSK调制模式，单向通讯方式，提高了系统信号传输的抗干扰能力。结合本系统采用的SP12传感器及监视模块微处理器rfPIC12F675F的特性, 采用LF低频唤醒技术，分时发送和接收不同监视模块射频信号，从而解决信号碰撞干扰问题，并进一步节省系统能耗。2 系统的设计要求 引起轮胎漏气和爆胎的原因主要有： 轮胎工作温度过高； 轮胎气压过大； 轮胎使用时间过长； 轮胎负荷过大；汽车行驶速度过快。为使汽车能够处于安全的驾驶状态，驾驶者必须在行车过程中实时了解轮胎的超压、欠压、温度等工作状态，该系统具有以下的功能： 实时监测轮胎的压力、温度情况； 当某个轮胎过压、过热时，自动进行声、光报警； 当某个轮胎处于欠压状态时， 相应的欠压报警指示灯亮。本文分为胎压检测模块和中央监视模块两大部分： 首先，分别介绍了硬件系统的构成，给出了各模块的硬件电路设计方案；对系统中用到的主要芯片，如传感器SP12、内嵌UHF发射器的处理器rfPIC12F675、无线接收芯片rfXD0420、中央监视模块处理器PIC16F877、内置T6963C控制器的LCD等，简单介绍了其功能和特性。其次，为提高TPMS系统抗干扰性能和实现低功耗管理，引入了LF低频主动唤醒技术。再次，基于功能模块划分，结合LF唤醒电路和低功耗管理思想，提出了动态周期测量和发射数据的思想，并给出了相应的软件算法和程序。针对汽车轮胎所处环境恶劣、干扰严重的特点，引入了适合TPMS严格的射频通信环境的CRC数据校验算法；然后，定制了合理的通讯协议，使用了软件过滤等方法以提高检测数据和报警的可靠性和准确性。3 硬件设计本系统包括5个模块，4个用于轮胎内的监视模块，一个用于车内的接收模块。监视模块包括传感器和发射模块。传感器把测量到的压力与温度信号转换为电信号通过无线发射装置将信号发射出来。传感器发射出来的气压温度信息由接收模块接收处理后，在驾驶台上的显示器中显示出来，在行驶过程中实时地进行监视。显示方式如LED、LCD或语音提示等都可依实际要求来设计。轮胎监测模块受中央主机控制模块低频LF信号控制，定间隔分时进入工作模式，其余时间处于休眠状态。3.1 轮胎监视模块的硬件设计 汽车轮胎独特的工作环境条件决定了胎压实时监测的压力传感器的高要求： 要求宽温区，宽电源电压范围内较高的精度和可靠性；低功耗要求；恶劣环境无线信号传输稳定性要求。本系统使用英飞凌(Infineon)公司的SP12轮胎气压温度加速度专用检测传感器。 因为节电和超小规模的要求，所以采用了SP12传感器。SP12是一种压电电阻传感器，除了可以测量压力和温度值之外，还集成有加速度传感器和电压传器，压力测量范围为100450kPa，温度测量范围为-40+125。待机模式平均耗电仅为13A。具有SPI串行通讯口，可以更方便的与控制器组成单片机系统。 rfPIC12F675F是Microchip公司推出的单片集成内嵌射频无线数据发射器的8 位CMOS微控制器。102414 位可编程EPROM，648字节数据存储器，1288字节EEPROM数据存储器，16个特殊功能的硬件寄存器；看门狗定时器，低功耗睡眠模式，6个通用I/O 等功能；工作电压2555V，低功耗睡眠模式电流为500A。内嵌UHF ASK/FSK 发射器，射频频率范围为230930MH z，可调节输出功率+6-15dBm，ASK数据发射速率040kbps，FSK数据发射速率0 20kbps；PLL锁相，集成晶体振荡器和VCO，电路仅需少量外部元件。符合US FCC Part 15231和European EN3002