基于PIC-單片機的通用胎壓監(jiān)測系統(tǒng)的設計外文翻譯完成版(共13頁)

1、精選優(yōu)質文檔-傾情為你奉上畢業(yè)設計(論文)外文資料翻譯 系 別： 電子信息系 專 業(yè)： 通信工程 班 級： B 姓 名： 李 莎 學 號： B 外文出處： 網(wǎng)絡資源 附 件： 1. 原文； 2. 譯文 2013年03月專心-專注-專業(yè)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 pr

2、oblems 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 stabi

3、lity 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 cent

4、ral 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 b

5、looey 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 P

6、ressure 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,

7、 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

8、 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

9、, 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 co

10、uld 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 ar

11、e 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 be

12、come 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 p

13、rocessor, 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 rfPIC12F6

14、75F 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 te

15、mperature 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

16、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 Part

17、s 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 wit

18、h 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 soft

19、ware 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

20、 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, receivi

21、ng 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 receiv

22、e 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-frequen

23、cy 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, w

24、ide 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

25、-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 averag

26、e 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 progra

27、mmable 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

28、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 EN ts 15231 FCC

29、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

30、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 t

31、ransmit 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 mod

32、ulation. 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,

33、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

34、 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 sensiti

35、vity 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 pe

36、rformance, 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,

37、 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, tand

38、em 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 beca

39、use 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, co

40、nfigure 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 comp

41、letion 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 tem

42、perature 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 t

43、he 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

44、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 modul

45、e 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 cal

46、culating 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, i

47、n 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.譯文：基于PIC 單片機的通用胎壓監(jiān)測系統(tǒng)的設計

48、1 引言隨著高速公路網(wǎng)的蓬勃興起，交通的日趨發(fā)達，車輛行駛速度的不斷攀升，交通隱患的防范問題迫在眉睫，如因車胎漏氣和爆炸等原因造成的交通事故，很多是由輪胎的工作溫度過高或者不合理胎壓引起的。研究汽車輪胎胎壓監(jiān)測系統(tǒng)，就對現(xiàn)代汽車行駛時的經(jīng)濟性、安全性和操縱穩(wěn)定性具有尤為重要的現(xiàn)實意義。PIC單片機的輪胎壓力通用監(jiān)測系統(tǒng)的硬件組成及軟件設計方法，闡述了基于英飛凌SP12傳感器和帶ASK/FSK調(diào)制發(fā)射芯片的rfPIC12F675F微控制器的輪胎監(jiān)測模塊設計方案和基于PIC16F877A單片機的中央主機接收模塊的設計方案，并給出了模塊硬件電路以及相關程序框圖、通信協(xié)議和算法等；該系統(tǒng)可隨時測定每個

49、輪胎內(nèi)部的實際溫度、瞬壓、加速度和傳感器電壓,確定故障輪胎并實時發(fā)出警告，有效避免事故的發(fā)生；該方案的提出有利于國內(nèi)TPMS產(chǎn)品的普及和功能優(yōu)化。 權威的研究結果表明，保持標準的輪胎氣壓和及時發(fā)現(xiàn)輪胎故障是防止爆胎的關鍵，這就使對輪胎充氣壓力實行監(jiān)測顯得非常重要。TPMS( Tire Pressure Monitoring System )，主要用于在汽車行駛時實時的對輪胎氣壓進行自動監(jiān)測。目前各國研制的輪胎氣壓報警系統(tǒng)主要分為兩種類型：一種是間接式，它通過汽車ABS( 防抱制動系統(tǒng)) 的輪速傳感器及輪胎的力學模型，間接求出輪胎氣壓，以達到監(jiān)視輪胎氣壓的目地；另一種是直接式，它利用安裝在每一個

50、輪胎里的以鋰離子電池為電源的壓力傳感器來直接測量輪胎的氣壓，并通過無線調(diào)制發(fā)射到安裝在駕駛臺的監(jiān)視器上，而監(jiān)視器隨時顯示各種輪胎氣壓，駕駛者可以直觀地了解各個輪胎的氣壓狀況，當輪胎氣壓太低或有滲漏時，系統(tǒng)就會自動報警，確保行車安全。輪胎氣壓監(jiān)測系統(tǒng)是汽車上一種新的主動安全技術產(chǎn)品，近年來，在國內(nèi)外發(fā)展迅速。由于它能夠實時監(jiān)測汽車輪胎的氣壓和溫度情況，并能及時給駕駛員以警告，因而可以最大限度地避免由爆胎引發(fā)的交通事故，提高了汽車的行車安全。綜述了汽車輪胎氣壓監(jiān)測系統(tǒng)的發(fā)展，包括間接式輪胎氣壓監(jiān)測系統(tǒng)、直接式輪胎氣壓監(jiān)測系統(tǒng)和下一代無電池輪胎氣壓監(jiān)測系統(tǒng)(被動式TPMS)。展望了未來輪胎氣壓監(jiān)測技

51、術的發(fā)展趨勢：無電池TPMS將取代現(xiàn)有類型，成為未來TPMS發(fā)展的主流。 無線信號傳輸?shù)姆€(wěn)定性可靠性不足、電池壽命問題、傳感器壽命和耐久性等問題，是目前T PMS產(chǎn)品中普遍存在的問題。本系統(tǒng)除傳感器外，均采用Microchip公司的收發(fā)芯片及微控制處理器，能耗低，兼容性好，可靠性高。并采用FSK調(diào)制模式，單向通訊方式，提高了系統(tǒng)信號傳輸?shù)目垢蓴_能力。結合本系統(tǒng)采用的SP12傳感器及監(jiān)視模塊微處理器rfPIC12F675F的特性, 采用LF低頻喚醒技術，分時發(fā)送和接收不同監(jiān)視模塊射頻信號，從而解決信號碰撞干擾問題，并進一步節(jié)省系統(tǒng)能耗。2 系統(tǒng)的設計要求 引起輪胎漏氣和爆胎的原因主要有： 輪胎工

52、作溫度過高； 輪胎氣壓過大； 輪胎使用時間過長； 輪胎負荷過大；汽車行駛速度過快。為使汽車能夠處于安全的駕駛狀態(tài)，駕駛者必須在行車過程中實時了解輪胎的超壓、欠壓、溫度等工作狀態(tài)，該系統(tǒng)具有以下的功能： 實時監(jiān)測輪胎的壓力、溫度情況； 當某個輪胎過壓、過熱時，自動進行聲、光報警； 當某個輪胎處于欠壓狀態(tài)時， 相應的欠壓報警指示燈亮。本文分為胎壓檢測模塊和中央監(jiān)視模塊兩大部分： 首先，分別介紹了硬件系統(tǒng)的構成，給出了各模塊的硬件電路設計方案；對系統(tǒng)中用到的主要芯片，如傳感器SP12、內(nèi)嵌UHF發(fā)射器的處理器rfPIC12F675、無線接收芯片rfXD0420、中央監(jiān)視模塊處理器PIC16F877、

53、內(nèi)置T6963C控制器的LCD等，簡單介紹了其功能和特性。其次，為提高TPMS系統(tǒng)抗干擾性能和實現(xiàn)低功耗管理，引入了LF低頻主動喚醒技術。再次，基于功能模塊劃分，結合LF喚醒電路和低功耗管理思想，提出了動態(tài)周期測量和發(fā)射數(shù)據(jù)的思想，并給出了相應的軟件算法和程序。針對汽車輪胎所處環(huán)境惡劣、干擾嚴重的特點，引入了適合TPMS嚴格的射頻通信環(huán)境的CRC數(shù)據(jù)校驗算法；然后，定制了合理的通訊協(xié)議，使用了軟件過濾等方法以提高檢測數(shù)據(jù)和報警的可靠性和準確性。3 硬件設計本系統(tǒng)包括5個模塊，4個用于輪胎內(nèi)的監(jiān)視模塊，一個用于車內(nèi)的接收模塊。監(jiān)視模塊包括傳感器和發(fā)射模塊。傳感器把測量到的壓力與溫度信號轉換為電信

54、號通過無線發(fā)射裝置將信號發(fā)射出來。傳感器發(fā)射出來的氣壓溫度信息由接收模塊接收處理后，在駕駛臺上的顯示器中顯示出來，在行駛過程中實時地進行監(jiān)視。顯示方式如LED、LCD或語音提示等都可依實際要求來設計。輪胎監(jiān)測模塊受中央主機控制模塊低頻LF信號控制，定間隔分時進入工作模式，其余時間處于休眠狀態(tài)。3.1 輪胎監(jiān)視模塊的硬件設計 汽車輪胎獨特的工作環(huán)境條件決定了胎壓實時監(jiān)測的壓力傳感器的高要求： 要求寬溫區(qū)，寬電源電壓范圍內(nèi)較高的精度和可靠性；低功耗要求；惡劣環(huán)境無線信號傳輸穩(wěn)定性要求。本系統(tǒng)使用英飛凌(Infineon)公司的SP12輪胎氣壓溫度加速度專用檢測傳感器。 因為節(jié)電和超小規(guī)模的要求，所

55、以采用了SP12傳感器。SP12是一種壓電電阻傳感器，除了可以測量壓力和溫度值之外，還集成有加速度傳感器和電壓傳器，壓力測量范圍為100450kPa，溫度測量范圍為-40+125。待機模式平均耗電僅為13A。具有SPI串行通訊口，可以更方便的與控制器組成單片機系統(tǒng)。 rfPIC12F675F是Microchip公司推出的單片集成內(nèi)嵌射頻無線數(shù)據(jù)發(fā)射器的8 位CMOS微控制器。102414 位可編程EPROM，648字節(jié)數(shù)據(jù)存儲器，1288字節(jié)EEPROM數(shù)據(jù)存儲器，16個特殊功能的硬件寄存器；看門狗定時器，低功耗睡眠模式，6個通用I/O 等功能；工作電壓2555V，低功耗睡眠模式電流為500A。內(nèi)嵌UHF ASK/FSK 發(fā)射器，射頻頻率范圍為230930MH z，可調(diào)節(jié)輸出功率+6-15dBm，ASK數(shù)據(jù)發(fā)射速率040kbps，F(xiàn)SK數(shù)據(jù)發(fā)射速率0 20kbps；PLL鎖相，集成晶體振蕩器和VCO，電路僅需少量外部元件。符合US FCC Part 15231和European E