汽車倒泊防撞報警器的設計畢業(yè)設計論文.doc

畢業(yè)設計（論文）題目： 汽車倒泊防撞報警器的設計 畢業(yè)設計（論文）原創(chuàng)性聲明和使用授權說明原創(chuàng)性聲明本人鄭重承諾：所呈交的畢業(yè)設計（論文），是我個人在指導教師的指導下進行的研究工作及取得的成果。盡我所知，除文中特別加以標注和致謝的地方外，不包含其他人或組織已經(jīng)發(fā)表或公布過的研究成果，也不包含我為獲得 及其它教育機構的學位或學歷而使用過的材料。對本研究提供過幫助和做出過貢獻的個人或集體，均已在文中作了明確的說明并表示了謝意。作 者 簽 名： 日 期： 指導教師簽名： 日期： 使用授權說明本人完全了解 大學關于收集、保存、使用畢業(yè)設計（論文）的規(guī)定，即：按照學校要求提交畢業(yè)設計（論文）的印刷本和電子版本；學校有權保存畢業(yè)設計（論文）的印刷本和電子版，并提供目錄檢索與閱覽服務；學?？梢圆捎糜坝?、縮印、數(shù)字化或其它復制手段保存論文；在不以贏利為目的前提下，學校可以公布論文的部分或全部內(nèi)容。作者簽名： 日 期： 學位論文原創(chuàng)性聲明本人鄭重聲明：所呈交的論文是本人在導師的指導下獨立進行研究所取得的研究成果。除了文中特別加以標注引用的內(nèi)容外，本論文不包含任何其他個人或集體已經(jīng)發(fā)表或撰寫的成果作品。對本文的研究做出重要貢獻的個人和集體，均已在文中以明確方式標明。本人完全意識到本聲明的法律后果由本人承擔。作者簽名： 日期： 年 月 日學位論文版權使用授權書本學位論文作者完全了解學校有關保留、使用學位論文的規(guī)定，同意學校保留并向國家有關部門或機構送交論文的復印件和電子版，允許論文被查閱和借閱。本人授權 大學可以將本學位論文的全部或部分內(nèi)容編入有關數(shù)據(jù)庫進行檢索，可以采用影印、縮印或掃描等復制手段保存和匯編本學位論文。涉密論文按學校規(guī)定處理。作者簽名：日期： 年 月 日導師簽名： 日期： 年 月 日注 意 事 項1.設計（論文）的內(nèi)容包括：1）封面（按教務處制定的標準封面格式制作）2）原創(chuàng)性聲明3）中文摘要（300字左右）、關鍵詞4）外文摘要、關鍵詞 5）目次頁（附件不統(tǒng)一編入）6）論文主體部分：引言（或緒論）、正文、結論7）參考文獻8）致謝9）附錄（對論文支持必要時）2.論文字數(shù)要求：理工類設計（論文）正文字數(shù)不少于1萬字（不包括圖紙、程序清單等），文科類論文正文字數(shù)不少于1.2萬字。3.附件包括：任務書、開題報告、外文譯文、譯文原文（復印件）。4.文字、圖表要求：1）文字通順，語言流暢，書寫字跡工整，打印字體及大小符合要求，無錯別字，不準請他人代寫2）工程設計類題目的圖紙，要求部分用尺規(guī)繪制，部分用計算機繪制，所有圖紙應符合國家技術標準規(guī)范。圖表整潔，布局合理，文字注釋必須使用工程字書寫，不準用徒手畫3）畢業(yè)論文須用a4單面打印，論文50頁以上的雙面打印4）圖表應繪制于無格子的頁面上5）軟件工程類課題應有程序清單，并提供電子文檔5.裝訂順序1）設計（論文）2）附件：按照任務書、開題報告、外文譯文、譯文原文（復印件）次序裝訂3）其它目 錄一、畢業(yè)設計（論文）開題報告二、畢業(yè)設計（論文）外文資料翻譯及原文三、學生“畢業(yè)論文（論文）計劃、進度、檢查及落實表”四、實習鑒定表xx大學xx學院畢業(yè)設計（論文）開題報告題目： 汽車倒泊防撞報警器的設計 系 專業(yè)學 號： 學生姓名： 指導教師： （職稱： ） （職稱： ）xxxx年x月xx日 課題來源由于隨著科學技術和汽車工業(yè)的發(fā)展，許許多多的汽車安全裝置也得到大力的發(fā)展。汽車上面安裝防撞警報器能夠極大的方便司機的駕駛，保障司機的安全，并且能在緊急情況下能自動剎車防止汽車之間的相撞。隨著人們安全意識的提高，在汽車上安裝防撞倒泊警報器將必不可少?？茖W依據(jù)（包括課題的科學意義；國內(nèi)外研究概況、水平和發(fā)展趨勢；應用前景等）在當今社會，知識的實用性越來越得到重視。如何從海量的知識群中找出有用的知識并付諸實踐，這是很值得摸索的。單片機的應用日益普及，汽車的數(shù)量急劇增加，保障汽車駕駛人員的安全也變得越來越重要了。目前在汽車警報器經(jīng)過20多年的發(fā)展 ，已經(jīng)歷了從開始的由單片機的蜂鳴器到由頻率控制聲音的急促報警到進一步的可視的智能化防撞報警系統(tǒng)。汽車防撞裝置主要是通過車與障礙物之間的距離，車速信號的發(fā)射與接收由信號控制系統(tǒng)既是利用單片機來控制車速。并發(fā)出不同頻率的報警信號。當車速與車距距離進入比較危險的狀態(tài)時，單片機自動控制發(fā)出緊急制動信號剎車，以此來達到防撞的目的。由上述可知，汽車與障礙物的距離只有在危險距離狀態(tài)才有發(fā)生碰撞的可能，汽車防撞裝置系統(tǒng)的設計任務主要是采集汽車與障礙物的距離和本車車速，并與當時車速下安全警報距離與危險距離之間進行比較，判斷汽車與障礙物的距離是否安全。當達到的安全警報距離時能發(fā)出聲音報警。研究內(nèi)容在倒車時不斷測量汽車尾部與其后面障礙物的距離，并實時顯示其與障礙物之間的距離，在不同的距離范圍內(nèi)發(fā)出不同的報警信號，并且提高報警系統(tǒng)的穩(wěn)定性，以提高汽車倒車時的安全性。本文設計了一種超聲波汽車倒泊防撞報警器，本報警器具有以下功能：最大測距4.9m，最小測距0.1m，實時顯示測得的距離；在不同的時間利用三個不同的超聲波傳感器進行測距，能夠有效的提高報警的穩(wěn)定性。在不同的危險距離范圍內(nèi)發(fā)出不同的頻率報警信號，駕駛員還可以根據(jù)個人需要調(diào)整設置報警距離。利用555來控制蜂鳴器的發(fā)聲頻率，直接運用單片機的i/o口控制報警器的工作。能夠大大降低軟件的復雜程度。該報警器與其它報警器相比具有功能多、硬件電路簡單、工作穩(wěn)定可靠等優(yōu)點。擬采取的研究方法、技術路線、實驗方案及可行性分析研究方法：理論聯(lián)系實際。技術路線：理論聯(lián)系實際。實驗方案：對比“基于at89c51單片機的超聲波防撞報警系統(tǒng)”跟“基于at89c2051單片機的超聲波防撞報警系統(tǒng)”，前者性價比更高，所以選擇前者?？尚行苑治觯耗軌蚶碚撀?lián)系實際解決實際性的問題。此方案可行。研究計劃及預期成果初步討論基于at89c51單片機來實現(xiàn)汽車倒泊防撞警報器的設計，分析了運用at89c51和at89c2051作為主控制器的兩種方案。重點介紹了at89c51來實現(xiàn)的方案。對控制器，超聲波發(fā)射電路，超聲波接收電路，高低頻報警電路，led顯示電路等模塊，以及運用單片機的i/o口如何具體的控制作了一定的說明。第四部分中，介紹系統(tǒng)的硬件框圖、軟件流程圖、中斷子程序流圖等，給出了具體的軟件實現(xiàn)的方案。利用51 系列單片機設計的測距儀便于操作、讀數(shù)直觀。測距儀工作穩(wěn)定, 能滿足一般近距離測距的要求, 且成本較低、有良好的性價比。特色或創(chuàng)新之處考慮非常周全，不但提供了相應的理論基礎知識，一定的電子電路圖，還為詳細的設計過程截取圖片已具備的條件和尚需解決的問題對于at89c51單片機來實現(xiàn)汽車的倒泊防撞警報器尚取得了一定進展，但是還是有很多的不足之處：（1）應該引入更加完善的顯示系統(tǒng)，是司機能更加清楚的了解倒車時的情況。（2）引入先進的語音模塊，通過人性化的語音報警信號。（3）在緊急情況，應該自動使汽車緊急剎車，防止汽車與障礙物之間相撞。（4）應該對該警報器進行實際的測量，適當?shù)倪M行調(diào)節(jié)，最大限度的減少誤差。但是未來利用單片機來實現(xiàn)汽車的倒泊防撞警報器仍然有廣闊的前景，隨著單片機的功能日漸增強，能夠使報警更加人性化指導教師意見 指導教師簽名：年 月 日教研室（學科組、研究所）意見 教研室主任簽名： 年 月 日系意見 主管領導簽名： 年 月 日外文原文microelectronic engineeringsouth koreabschool of information and communication engineering, college of engineering, inha university, incheon 402-751, south korea cdepartment of electrical engineering, college of engineering, choongang university,seoul 156-756, south korea.available online 17 february 2006. abstractwe report on the fabrication of a polymer-based 2.5gbps4 channel optical interconnecting micro-module for optical printed circuit board (o-pcb) application. an optical waveguide array is used for optical transmission from vertical surface emitting laser (vcsel) array to photodiode (pd) array and the built-in 45 waveguide mirrors are used for vertical coupling. the optical waveguide array and the 45 mirrors are fabricated by uv imprint process in one-step. we fabricate microlensed vcsels by micro-inkjetting method, which reduced radiation angle of vcsel from 18 to 15 for better light coupling. we use solder ball array and pin array for alignment between o-pcb and the electrical sub-boards with alignment mismatch below 10m in x, y and z axis. the fabricated optical interconnection module transmits data at the rate of 2.5gbps per channel.keywords: optical interconnection; photonic integrated circuit; micro-fabrication; uv embossingarticle outline1. introduction 2. fabrication of waveguide array and 45 mirrors 3. microlensed vcsel 4. passive alignment 5. optical interconnect modules 6. conclusion acknowledgements references1. introductionin the progresses of microprocessor and the input-output (io) devices, the need for higher bandwidth is rapidly growing. high speed interconnects are demanding next generation io interconnects of highly increased data capacity because todays io interconnects are suffering bottleneck in bandwidth at the io interface. many attempts to increase the io interconnect bandwidth have emerged 1. these attempts to extend electrical interconnect in more bandwidth manner are hard to solve fundamental problems facing the limitation of electrical properties over gigabits per channel data capacity.operation of electrical interconnect schemes in gigabit regime will meet bottlenecks related to the properties of electrical interconnects, including material properties, skew, jitter, emi, and power consumption. to improve the performances of electrical interconnects, many efforts in signal processing techniques such as pre-emphasis, equalization, multilevel signaling, and coding, deterministic jitter are needed to keep the trace of the bandwidth progress 2, 3 and 4.optical interconnection has a potential as an alternative approach to solve these problems because optical interconnection has many advantages over electrical interconnection such as high frequency, high bandwidth, light, immunity to emi, low skew, low jitter, no need of ground line, easy for impedance matching.to realize an optical interconnection module for o-pcb application, various photonic devices like light sources, detector arrays, and waveguide arrays are needed. the waveguides are interconnected to light sources and photo-detectors in a multiple array. the 45 waveguide mirrors are used for interconnecting vcsel arraywaveguide array/waveguide arraypd array. once the o-pcb is designed and fabricated it has to be put together with the existing electrical circuits such as driving circuits for micro-lasers and micro-detectors. hence, we need micro-fabrication techniques for realizing optical interconnection module.we carried out micro-fabrication for optical interconnection module, which include design and fabrication of waveguides, coupling schemes and passive alignment. for this, we focus on the following issues: one is the concurrent fabrication of a waveguide array and 45 mirrors in one-step in order to reduce the number of processing steps for low-cost production and another is a method to improve coupling efficiency between vcsel arraywaveguide array/waveguide arraypd array including the passive alignment method between the different parts of the optical interconnection module. this paper demonstrates a micro-fabrication of optical interconnection module to be used for the realization of optical printed circuit board (o-pcb) 7 and 8.2. fabrication of waveguide array and 45 mirrorsto use polymers as materials of the waveguide, embossing technique is used because of its relatively easy fabrication process. we fabricated polymer waveguides by uv embossing, which also involves fabrication of mold and replica. uv curable polymers are used as materials of waveguides and silicon mold is used to form waveguide patterns. for vertical coupling between vcsel array and waveguide array and between the waveguide array and the pd array, we have to utilize mirror face at each end of the waveguide. to achieve this process, waveguide mold equipped with 45 faces at each end of the mold is needed to form the vertical coupling structure in a single fabrication step. we made a 12 channel silicon waveguides mold, which has 45 mirror face at the ends of each waveguide. the dimension of the waveguide is 50m width and 50m height and the waveguide layout pitch is 250m and the length is 7cm. with this mold, we performed uv embossing to make embedded type waveguides.to fabricate a 12 channel silicon waveguides mold, we etched silicon substrate with koh-saturated isopropanol solutions in two steps: first is to make a vertical coupling path for the waveguides and the other is to make 45 slope for the fabrication of mirror faces. first, a metallic mask is patterned on the silicon substrate and the silicon is vertically etched with koh to form a waveguide pattern. in the next step to form 45 slope, a thin film of sio2 is grown on patterned waveguide. and photoresist is patterned at the end of the each waveguide structure and the ends of the waveguides are etched with koh-saturated isopropanol solution to form 45 slope. after the sio2 is stripped, the process of fabricating silicon mold equipped with 45 mirror is completed.we fabricated 12 channel embedded waveguide array by uv embossing using the prefabricated silicon mold. waveguide fabrication process is shown in fig. 1. uv curable polymer, which is used as cladding layer with index as 1.45 at 850nm wavelength, is dropped in the hollow cavity of a transparent substrate such as pdms template. after silicon mold is pressed on template the uv light is irradiated. silicon mold is detached and metallic film is coated on the 45 slope at the end of the waveguide to enhance coupling efficiency. and then the core polymer is dropped and a flat substrate is covered and pressed onto the core material which is also uv curable polymer with refractive index of 1.47 at 850nm wavelength. the uv light is irradiated once again. after the upper and lower templates are detached, we can get a complete array of polymer waveguides with built-in 45 mirror face at each end of the waveguide.view within article3. microlensed vcselone of the approaches to collimate the light from vcsel arrays to the waveguide is the use of microlenses 9 and 10. this method offers an increase in coupling efficiency and alignment tolerance. the volume of a polymer drop to fabricate these lenses is approximately a few tens of picoliters. we are able to control the size of the microlenses by controlling the amount of the polymer drops and by controlling the viscosity of the materials. uv curable polymer is used for inkjetting, of which the viscosity and the refractive index are 300cps and 1.51 at 850nm wavelength. shows one of the microlensed vcsel array and microlensed vcsel has a microlens formed by the inkjetting method on the aperture of vcsel. inkjetting of uv curable resin on the vcsel, lens material is aligned automatically on the aperture of vcsel. shows a view of the system where the output power from the microlensed vcsel arrays is measured for their divergence. the divergence angle of the laser light from the vcsel is shown to become narrower by using microlenses by the collimating effect pf the light from vcsel. because of the microlens, the higher order modes from the vcsel are suppressed by the cavity effect 10. the emitted output from the vcsel cavity is reflected back by microlens layer and is focused on the vcsel cavity. during this process, the divergence angle of the vcsel is reduced. in this case, the divergence angle of the vcsel decreased from 18 to 15 after forming microlens. we conducted simulation study about the coupling efficiency between vcsel and the waveguide by using the ray tracing method. as the divergence angle of the vcsel was put into the calculation, the coupling efficiency of the vcsel with microlens was found to be 0.44db is 0.96db which were better than that of vcsel without microlens as 1.40db. here dimension of waveguide is 50m width, 50m height and 7cm length. refractive indices of the core and the cladding are 1.47 and 1.45, respectively, at 850nm wavelength. the distance between the vcsel and the waveguide is 100m.view within article4. passive alignmentsolder ball array and pin array are placed on the electrical sub-boards to bond the o-pcb and the electrical sub-boards with high precision. for precision alignment, solder ball array in diameter of 450m are used to thermally attach to the chip module. the solder ball array can be used for vertically alignment between the main o-pcb and the sub-boards within a mismatch below 10m. the size of the solder ball is 500m on average with standard error of 5m.two types of pin arrays are used. one array with diameter of 1mm is for alignment and the other with diameter of 200m is for electrical interconnection. the 1mm pin array is used for lateral alignment between the main o-pcb and the sub-boards. because of the impedance match, the pin array of the electrical interconnection is limited. similar to solder ball array alignment tolerance of the pin array, about 10m, depends on variation of diameter of pin. the size of the pin is 1mm on average with standard error of 10m.we conducted simulation study about the coupling efficiency between the vcsel-waveguide pair and the waveguide-pd pair by ray tracing. with the variation of misalignment of x, y, and z axis we calculated the coupling efficiencies. from the calculation we obtained the total coupling loss within 2.30db for the worst case of having position errors as large as 10m in the xz axis and in the y axis, respectively. for example, when the position misalignment is 10m in the xz axis and in the y axis, the coupling loss between vcsel-waveguide is 1.59db and the coupling loss between vcsel-waveguide is 0.71db. from the previous results, one can achieve the alignment between solder ball array and pin array can be achieved for alignment between main o-pcb and sub-boards with precision as about 10m in xz axis and in y axis, respectively. here the dimension of the waveguide is 50m width and 50m height. the refractive indices of the core and the cladding are 1.47 and 1.45, respectively, at 850nm wavelength. the distance between the vcsel and the waveguide is 100m in the y axis.view within article5. optical interconnect moduleswe demonstrated the use of optical interconnection module for the assembly of o-pcb having four 2.5gbps channels. the optical interconnection module, which includes e/o (electrical/optical) conversion unit, is attached to the o-pcb with solder ball. the solder ball bonding is designed to accomplish the alignment between the waveguide structure and the electric circuit with high precision. the o-pcb prototype consists of main body of o-pcb and two electrical sub-boards. the main o-pcb has embedded waveguide which is the medium of optical interconnection. the two sub-boards are used for electrical-to-optical (e/o) or optical-to-electrical (o/e) conversion. the vcsel array and the pd array are bonded to interconnect the waveguide to the bottom of the sub-board. the driving circuits are placed on the opposite side to vcsel array and pd array. the power, ground and other electrical control signal are supplied through the pin grid. the main o-pcb is placed on the e-pcb within a rectangular area of 70mm10mm at the center of the e-pcb.the overall planar size of the o-pcb is 200mm80mm and thickness is 1mm. the uv embossed waveguide including the 45 mirror for vertical coupling is inserted into the e-pcb and is glues with uv-epoxy. the sub-boards including vcsel array/pd array are designed and fabricated using conventional analysis of microstrip line.view within articlewe finally evaluated the quality of the optical interconnection module. first, we tested the waveguide array with 45 mirror face. the total losses of the waveguide include the propagation loss, the coupling loss, the 45 mirror loss and the insertion loss. and an average total loss is 7.9db for a waveguide of 7cm length and their variation is within 1db. for the worst case, in 12 channel, the total loss was 8.9db.to demonstrate the data transmission performance, we utilized aligned optical interconnection module .a 2.5gbps psudo-random binary system (prbs) pattern were put in to the vcsel driver via the pin grid and the electrical output signal of the module were connected to a wide-band oscilloscope. an eye pattern of 2.5gbps transmission was clearly observed without any significant distortion.view within article6. conclusionwe performed micro-fabrication for optical interconnection module. the optical waveguide array is fabricated by uv imprint process. the 45 mirrors faces are fabricated as an integrated part of the silicon waveguide mold for low-cost one-step processing. we fabricated microlensed vcsels by micro-inkjetting method and found a significant increase in the improvement of the coupling efficiency reaching 0.96db. use of solder ball array and pin array for the alignment between the o-pcb and the sub-boards could be achieved with a pr