輕型貨車車架設計及有限元分析畢業(yè)設計論文

輕型貨車車架設計及有限元分析畢業(yè)設計論文,輕型,貨車,車架,設計,有限元分析,畢業(yè)設計,論文 畢 業(yè) 設 計（論 文）外 文 參 考 資 料 及 譯 文譯文題目： Automotive safety systems and technology research and analysis 汽車安全系統(tǒng)技術研究分析 學生姓名： 學 號： 專 業(yè)： 車輛工程 所在學院： 機電工程學院 指導教師： 職 稱： 年 01 月 15 日說明：要求學生結合畢業(yè)設計（論文）課題參閱一篇以上的外文資料，并翻譯至少一萬印刷符（或譯出 3千漢字）以上的譯文。譯文原則上要求打?。ㄈ缡謱懀宦捎?400字方格稿紙書寫） ，連同學校提供的統(tǒng)一封面及英文原文裝訂，于畢業(yè)設計（論文）工作開始后 2周內完成，作為成績考核的一部分。Automotive safety systems and technology research and analysisAbstract: auto parts of good and bad will directly affect the safety of the car， are directly related to the peoples life safety and security in wealth. This article mainly from the cars active safetytechnology and passive safety technology two aspects elaborated the importance of car parts， and how to improve the safety of the car. Key words: automobile， active safety technology， passive safety technology As traffic tools of the modernization and absolute number increase sharply， traffic accidents are also increasing. Car accident has become severe global social issues. Undoubtedly， advanced auto safety facilities are the driving safety indispensable safeguard. So， we should start， from technology to research and development of high performance， high safety car， also want to strengthen the regular inspection in cars， so timely maintenance investigation， make cars often in good technical status， so as to improve the safety performance of the car. Here we introduced active safety technology and automobile car passive safety technology. Auto safety is according to the traffic accident happened before and after the classified. One is ina traffic accident take safety measures， especially before immediately will produce risk condition， drivers manipulate the steering wheel avoid or emergency brake to avoid traffic accidents. In the car， drive in usually to ensure the basic manipulation stability， drivers on the surrounding environment and to ensure the visual recognition sex drive the car itself， developed the basic performance ant-lock braking system (ABS)， prevent slippery drive system (ASR)，active suspension， power steering and four-wheel drive (4WD)， four-wheel steering (4WS)，lighting system， wiper， the rearview mirror， prevent from rear-end collision car alarm system and laser radar， etc. These security devices and technology， called active safety system， can also be called preventive security system. On the other hand， inorder to reduce traffic accidents and company by personnel directly suffer degree， ensure company take staff and pedestrian safety， says the security for passive safety， can also be called conflict safety. When after the accident， in order to prevent disasters， including prevent the expansion of fire and make crew from traffic accident can extricate the security devices and systems， called prevent disaster expand security system. Automobile active security technology ABS braking system Ant-lock Braking System (Braking System， lock do by ABS computers as ABS)，hydraulic device， the wheel speed sensors， brake hydraulic pipeline and electrical wiring etc.Their structures are shown below. ABS tasseled for the car in various driving conditions braking performance and brake safetyparticularly important， especially is emergency braking， can make full use of the peak between tire and road surface adhesion properties， improve performance and reduce automobile fightsideslip braking distance， give full play to the braking performance， but also increase the automobile braking process control. So as to reduce the possibility of car accidents. No installation ABS car， if the driving force trample brake pedal， wheel will rapidly lower speed， and finally wheels stop turning， but body because of inertia remains forward sliding. This phenomenon was at the wheel and pavement occur between larger “slip“， appear this kind of situation， the car tires of automobile lateral spreads almost disappear， so poor force will appear the following phenomena: (1)Steering stability fall: the steering wheel is ineffective， vehicle tail manipulation of curl， serious when vehicle circles or appear folding phenomenon; (2) Handling fall: manipulate the steering wheel and short of steering requirements; (3)Braking distance extended: more than general braking distance. So， we can imagine to have installed ABS system of the car safety is very important. The ASR drive torque control system ABS are used to prevent car braking process wheel lock， will wheel sliding rate control in ideal range， so as to shorten the braking distance， improve automobile braking direction stability and steering control， so as to improve the safety of the car. Along with the increase of vehicle performance requirements， not only in braking process required to prevent wheel lock， and asked the driver to prevent drive roller skating turn in the process， making cars in the direction stability， driving process steering control ability and acceleration performance， so are improved by the car drive torque steering system ASR (Accelerations Regulation) Slip. ASR is the perfect complement and ABS ASR， but most alone is set with ABS combined together， commonly used ABS/ASR says， called antiskid control system. ASR is mainly used to prevent car in the beginning， accelerate the wheels， guarantee slip in the car accelerated rate and improve the stability in bad pavement drive attached conditions. It makes no difference speed in the car lock ice roads and muddy road started and to improve its capacity， also can prevent high in speed by turning cars gliding pavement and rear lateral spreads phenomenon. Anyhow， prevent the wheel because ASR slip， can maximize the engine driving moment of cars had enough， ensure the longitudinal force， lateral force and manipulation of power，make cars in starting， steering and accelerate the process， in gliding and muddy road， in a mountain area downhill process can steadily driving， guarantees the safety， reducing tire wear and fuel consumption， and improves the car driving capability. VDC system ABS/ASR system successfully solves the brake and the car when driven direction stability problem， but cannot solve the vehicle steering stability problem driving direction. For example when steering road， inevitably by lateral and longitudinal force， only local surface can provide full lateral and longitudinal force， the pilot can control vehicles. If the ground adhesion ability lower lateral， will damage cars driving ability predetermined direction. Rainy days cars driving， often high-speed steering lateral sliding out， it is the ground because of insufficient lateral adhesion ability. To resolve the issue， and developed countries automobile industry recently in ABS/ASR system on the basis of the development of dynamic Control system (into car Dynamics Control， the abbreviation VDC Vehicle).The system of the car brake， driving， suspension， steering， engine and so on various mainassembly control system in function， structure organic ground comprehensive together， can make cars in all kinds of bad working conditions， such as ice road pavement， commuting， river bend pavement and took evasive action moving line， braking and acceleration and the downhill for different conditions， such as bearing， different type pressure and different levels of type wear all have good direction stability， to show the best driving performance. VDC applications， in braking， acceleration and steering aspects of drivers fully released request， is the car of active safety driving a new milestone. VDC of steering control system is mainly by driving for each wheel brake control and engine power output control to realize. For example， if the car turn left front wheel for steering the inadequate capacity tend to slip out of the corner， VDC system can measure imminent， just know lateral spreads left rear brake adopt appropriate measures. If at the same corner， because rearwheel tend to slip out of favor of lateral overmuch， VDC system is proper braking to front-right wheel failure， maintain the stability of the vehicle driving. In extreme cases， VDC system can also take reduce engine to reduce the power output， and to reduce the speed of the demand side adhesion ability to maintain the stability of the vehicle driving. Adopt VDC system， automobile in folio pavement or corner of pavement braking distance still can further reduce. CCS cars cruise control system Auto cruise Control System (Cruiser Control System， abbreviation for CCS)is can make automobile work in engine favorable speed range， reduce drivers driving manipulate labor intensity， improve the driving comfort the automatic driving device. Car cruising system (CCS) role is required by the driver: after a normally-closed switch， no speed on the accelerator pedal can automatically keep the speed， make the vehicle with the fixed speed. Using this device， when on the highway after a long time， the driver driving not have to control the accelerator pedal， reduce fatigue ， while reducing unnecessary speed change， can reduce save fuel. Auto cruise control system is the earliest development of the automotive electronic control system. This system USES another speed sensor， will speed signal input engine control microcomputer， by microcomputer control vacuum system work. This system can make use of the server， speed control switch lever and brake pedal on vacuum lift switches etc， its function and basic system the same. In this system， electronic control device can accord change of driving resistance， automatic regulation engine throttle Angle， make the speed constant. Such not only reduce unnecessary speed change， which saves fuel ， also reduced the drivers burden. The electronic cruise control system which is shown in figure 2. Automobile passive safety technology Seat belt Car seat belt is a safety device， it can in car collision or sharp turn， make crew to keep its original position as possible without mobile and rotation， avoid collision with in-car hard parts caused damage. Seat belts and airbags， as modern cars are safety devices， but the long history of the former， popularize the scope. The seemingly simple seat belt actually not “simple“. Attention has been at the forefront of traffic safety， through the analysis of general motors after a car accident found: seat belt not only makes people protect the lives， can be in more than half of the accident to reduce or even eliminate drivers， motorists are the chance of injury. Car collision or unexpected emergency braking force generated great inertia， will allow the driver and passenger and car windscreen， steering wheel， seat， collision happened objects such as secondary to drive is caused extremely easily crew serious damage， even drive occupant seats or threw the apex， seat belts can will ride in the seat. Bondage personnel When has the accident， which can effectively prevent the collision， and its buffer role can absorbs a great deal of kinetic energy， reduce rides personnel extent of the injuries. Fasten your seat belt airbags play our role is also an important condition. Because the airbagto maximize role for the ride in the impact of the physical location， sitting instant action have extremely strict and the requirements. Otherwise， the airbag started strong instantaneous wallops to head are fragile site， may cause serious damage， especially for children， this damage can be fatal. Even the most ordinary three belts， try a can timely in crash that lived rides the bundle， ensure the upper part of a ride in the airbag fully extended range， make the airbag most effectively play efficacy. Accordingly， must not because the car is equipped with airbags and feel carefree seat belt fastened， only to reduce or eliminate the traffic accident happen. The airbag When the front collision happened strong， because inertia， who rides the body forward fast moving， then seat belts and will try to “pull“ rides on person the body， absorb some of theimpact energy， while the airbag with “the eyepiece trend“ inflatable and completely open; Then the rides the upper body will sink to airbags， gas also began from the vent air uniform escaping， and absorbed most of the impact energy; Subsequently， the ride back seat and return to the body. Above the whole process is almost always happens in a flash， who rides the completelyin passive situation， in this case， the passive rely on auxiliary occupant protection system is the only option. Airbags development design is based on the protection on seat belt Co.， LTD; they cooperate with each other to ride the play the auxiliary protective effect. Seat belt usage in under the condition of the crew， balloon help reduce chest， head and facial injuries in the seriousness of the collision. When car collision happened before， the first isthe car to stop motion， car under the action of inertial force crews to go forward with the original speed still sport. Not wearing a seatbelt crews will and steering dish， front windscreen together， so it can be severely hurt; Wearing a seatbelt as car stop the crew can stop moving forwardmovement and gradually. If collision violent， crew forward movement of the seat belts， evenfaster in the complete stop before motion， still and in-car things together. If this fashion in steering the disk or within the popup balloon inflated dash， it can protect the occupant reduce the possibility of car together with things， more uniform dispersion head， chest， absorb the impact energy of movement， thus crew has added effect of seat belts. In addition to seat belts and airbags outside car passive safety technology includes car bumper， automobile safety glass， security body， occupant head and neck protection system (WHIPS)， etc. These vehicles to improve the safety performance has very important contribution.汽車安全系統(tǒng)技術研究分析摘要：汽車各部件的好與壞將直接影響汽車行駛的安全性，直接關系著人們的生命安全和產財安全。本文主要從汽車的主動安全技術和被動安全技術兩方面來闡述汽車各部件的重要性，并如何改善汽車行駛的安全性。 關鍵詞：汽車、主動安全技術、被動安全技術 隨著交通工具的現代化和絕對數量的急劇增長，車禍也不斷增加。汽車交通事故已成為嚴峻的全球性社會問題。毋庸置疑，先進的汽車安全設施是行車安全不可缺少的保障。所以，我們要從技術上入手，努力研究開發(fā)高性能、高安全性的汽車，同時也要加強對在用汽車的定期檢查，以便及時維修調查，使汽車經常處于良好的技術狀況，以提高汽車行駛的安全性能。 這里我們重點介紹汽車主動安全技術和汽車被動安全技術。汽車的安全性是按交通事故發(fā)生的前后加以分類的。一方面是在交通事故發(fā)生之前采取安全措施，特別當即將發(fā)生危險狀態(tài)時，駕駛者操縱方向盤避讓或者緊急制動以避免交通事故發(fā)生。汽車在通常的行駛中，為確保駕駛者的基本操縱穩(wěn)定性，對周圍環(huán)境的視認性和確保汽車本身的基本行駛性能，開發(fā)了防抱死制動系統(tǒng)(ABS)、防滑驅動系統(tǒng)(ASR)、主動懸架、動力轉向、四輪驅動(4WD)、四輪轉向 (4WS)、燈光照明系統(tǒng)、刮水器、后視鏡、防止車輛追尾的車距報警系統(tǒng)和激光雷達等。這些安全裝置和技術稱為主動安全系統(tǒng)，也可稱為預防安全系統(tǒng)。另一方面，為了盡量減少交通事故和司乘人員直接受害程度，保證司乘人員和行人的安全，稱這種安全性為被動安全，也可稱為沖突安全。當事故發(fā)生后，為了防止災害的擴大，包括防止火災和使乘員能從事故車輛中解脫出來的安全裝置和系統(tǒng)，稱為防止災害擴大的安全系統(tǒng)。 汽車主動安全技術 ABS 防抱死制動系統(tǒng) 防抱死制動系統(tǒng)(Anti-lock Braking System，簡稱 ABS)由 ABS 電腦、液壓裝置、車輪轉速傳感器、制動液壓管路及電器配線等組成。 ABS 系統(tǒng)對于汽車在各種行駛條件下的制動性能及制動安全尤為重要，特是緊急制動，能夠充分利用輪胎和路面之間的峰值附著性能，提高汽車抗側滑性能并縮短制動距離，充分發(fā)揮制動效能，同時增加了汽車制動過程中的可控性。從而減少了汽車事故發(fā)生的可能性。 沒有安裝 ABS 的汽車，如果在行駛中用力踩踏制動踏板，車輪會急速降低轉速，最后車輪停止轉動，但車身由于慣性依然保持向前滑動。這種現象在車輪與路面之間發(fā)生較大的“滑移” ，出現這種狀況時，汽車輪胎對路面的側滑摩差力幾乎消失，于是會出現下述現象： （1）轉向穩(wěn)定性下降：方向盤操縱不靈，車輛尾部上翹，嚴重時車輛打轉或出現折疊現象； （2）操縱性下降：操縱方向盤而達不到轉向要求； （3）制動距離延長：超過一般的制動距離。 所以，可想而知有無裝設 ABS 系統(tǒng)對汽車行駛的安全性是非常重要的。 ASR 驅動防滑控制系統(tǒng) ABS 用于防止汽車制動過程中車輪抱死，將車輪的滑移率控制在理想的范圍內，以縮短制動距離，提高汽車制動時方向穩(wěn)定性和轉向操縱性，從而提高汽車行駛的安全性。隨著對汽車性能要求的提高，不僅要求在制動過程中防止車輪抱死，而且要求在驅動過程中防止驅動輪滑轉，使汽車在驅動過程中的方向穩(wěn)定性、轉向控制能力和加速性能都得到提高，因此采用了汽車驅動防滑轉向系統(tǒng) ASR（Accelerations Slip Regulation） 。ASR是 ABS 的完善和補充，ASR 可單獨設置，但大多數是與 ABS 組合一起，常用 ABS/ASR表示，稱為防滑控制系統(tǒng)。 ASR 主要用來防止汽車在起步、加速時車輪的滑轉，保證汽車在加速過程中的穩(wěn)定性并改善在不良路面上的驅動附著條件。它可以使無差速鎖的汽車在冰雪路面和泥濘道路上起步并改善其通行能力，還可以防止在車速較高并通過滑溜路面又轉彎時汽車后部的側滑現象。 總之，ASR 由于防止了車輪的滑轉，便可最大限度地利用發(fā)動機的驅動力矩，保證汽車有足夠的縱向力、側向力和操縱力，使汽車在起動、轉向和加速過程中，在滑溜和泥濘路面上、在山區(qū)上下坡過程中都能穩(wěn)定地行駛，既保證了行車安全，減少輪胎磨損和燃油消耗，又改善了汽車的驅動性能。 VDC 系統(tǒng) ABS/ASR 系統(tǒng)成功地解決了汽車在制動和驅動時的方向穩(wěn)定性問題，但不能解決汽車轉向行駛的方向穩(wěn)定性問題。例如當汽車轉向行駛時，不可避免地受到側向和縱向力的作用，只有當地面能夠提供充分的側向和縱向力時，駕駛員才能控制住車輛。如果地面?zhèn)认蚋街芰Ρ容^低，就會損害汽車按預定方向行駛的能力。雨天汽車高速轉向行駛時，常常側向滑出，就是地面?zhèn)认蚋街芰Σ蛔愕木壒?。為解決此問題，最近汽車工業(yè)發(fā)達國家又在 ABS/ASR 系統(tǒng)的基礎上發(fā)展成汽車動態(tài)控制系統(tǒng)（Vehicle Dynamics Control，簡稱 VDC） 。這個系統(tǒng)把汽車的制動、驅動、懸架、轉向、發(fā)動機等各主要總成的控制系統(tǒng)在功能上、結構上有機地綜合在一起，可使汽車在各種惡劣工況下，如冰雪路面上、對開路面上、彎道路面上以及采取規(guī)避動作移線、制動、加速和下坡等工況時，對不同承載、不同輪胎氣壓和不同程度的輪胎磨損都有良好的方向穩(wěn)定性，表現出最佳的行駛性能。VDC 的應用，在制動、加速和轉向方面完全解脫對駕駛員的要求，是汽車的主動安全行駛方面的一個新的里程碑。 VDC 系統(tǒng)對轉向行駛的控制主要是借助于對各個車輪的制動控制和發(fā)動機功率輸出控制來實現的。例如汽車左轉彎時，若前輪因轉向能力不足而趨于滑出彎道，VDC 系統(tǒng)即可測知側滑即將發(fā)生，就采取適當制動左后輪的辦法。若在同一彎道上，因后輪趨于側向滑出而轉向過多，VDC 系統(tǒng)即采取適當制動右前輪的辦法，維持車輛的穩(wěn)定行駛。在極端情況下，VDC 系統(tǒng)還可采取降低發(fā)動機功率輸出的辦法降低行駛車速，減少對地面?zhèn)认蚋街芰Φ男枨髞砭S持車輛的穩(wěn)定行駛。采用 VDC 系統(tǒng)后，汽車在對開路面上或彎道路面上的制動距離還可進一步縮短。 CCS 汽車巡航控制系統(tǒng) 汽車巡航控制系統(tǒng)（Cruised Control System，縮寫為 CCS）就是可使汽車工作在發(fā)動機有利的轉速范圍內，減輕駕駛員的駕駛操縱勞動強度，提高行駛舒適性的汽車自動行駛裝置。 汽車巡航系統(tǒng)（CCS）的作用是：按司機所要求的速度閉合開關后，不用踩油門踏板就可以自動地保持車速，使車輛以固定的速度行駛。采用了這種裝置，當在高速公路上長時間行車后，司機就不用再去控制油門踏板，減輕了疲勞，同時減少了不必要的車速變化，可以減省燃料。 汽車巡航控制系統(tǒng)是最早開發(fā)的汽車電子控制系統(tǒng)之一。這種系統(tǒng)使用另外的車速傳感器，將車速信號輸入發(fā)動機控制微機，由微機控制真空系統(tǒng)工作。這種系統(tǒng)也要使用伺服器、車速控制開關桿和制動踏板上的真空解除開關等，其功能和基本系統(tǒng)相同。 在這個系統(tǒng)中，電子控制裝置可根據行駛阻力的變化，自動調節(jié)發(fā)動機油門開度，使行駛車速保持恒定。這樣既減少了不必要的車速變化，從而節(jié)省了燃料，同時也減輕了駕駛員的負擔。電子巡航控制系統(tǒng)的方框圖如圖 2 所示。 汽車被動安全技術 安全帶 汽車安全帶是一種安全裝置，它能在汽車發(fā)生碰撞或急拐彎時，使乘員盡可能保持原有的位置而不移動和轉動，避免與車內堅硬部件發(fā)生碰撞而造成傷害。安全帶與安全氣囊一樣，都是現代轎車上的安全裝置，但是前者的歷史悠久，普及范圍廣。 看似簡簡單單的安全帶其實并不“簡單” 。一直處在關注行車安全最前沿的通用汽車公司，通過分析大量意外事故后發(fā)現：汽車安全帶不但能使人保住性命，更能在超過半數的事故中減低甚至消除駕車者、乘車者受傷的機會。汽車發(fā)生碰撞或遇到意外緊急制動時產生的巨大慣性作用力，會使駕駛員、乘客與車內的方向盤、擋風玻璃、座椅靠背等物體發(fā)生二次碰撞，極易造成對駕乘員的嚴重傷害，甚至將駕乘員拋離座位或拋出車外，而安全帶能將駕乘人員束縛在座位上。發(fā)生意外時，它能有效防止二次碰撞，并且其緩沖作用能吸收大量動能，減輕駕乘人員的傷害程度。 系好安全帶也是安全氣囊發(fā)揮作用的一個重要條件。因為安全氣囊要發(fā)揮最大作用，對于駕乘者在撞擊瞬間的身體位置、坐姿以及動作有著極為嚴格的要求。否則，安全氣囊展開時強大的瞬間沖擊力對于頭部等較為脆弱的部位，可能造成嚴重的傷害，尤其對于兒童，這種傷害可能是致命的。即便是最普通的三點試安全帶，在撞車瞬間也可及時束住駕乘者的上半身，確保駕乘者處于安全氣囊完全展開的范圍內，使安全氣囊最有效地發(fā)揮功效。因此，千萬不要因為車中配備了安全氣囊而感到高枕無憂，只有系好了安全帶才能減輕或消除車禍的發(fā)生。安全氣囊 當汽車前部發(fā)生強烈的碰撞時，由于慣性，駕乘者的身體向前快速移動，這時安全帶便會盡力“拉住”駕乘者的身體，吸收部分沖擊能量，同時安全氣囊以“迅雷不及掩耳之勢”充氣并完全打開；接著駕乘者的身體上部便沉向安全氣囊，氣體也開始從氣囊的排氣口勻速逸出，并吸收了大部分沖擊能量；隨后，駕乘者身體向后并回到座椅上。以上整個過程幾乎都是發(fā)生在一瞬間的，駕乘者完全處于被動的局面，在這種情況下，被動的依靠輔助乘員保護系統(tǒng)是唯一的選擇。安全氣囊的開發(fā)設計就是基于安全帶有限的保護作用之上的，它們互相配合發(fā)揮對駕乘者的輔助保護作用。 在乘員使用安全帶的情況下，氣囊有助于減輕胸、頭和面部在碰撞時受傷的嚴重性。當汽車發(fā)生前碰撞時，首先是汽車要停止運動，車內乘員的慣性力作用下仍以原速度繼續(xù)向前運動。不系安全帶的乘員將會與轉向盤、前擋風玻璃相碰，因而可能受到嚴重傷害；系安全帶的乘員可以隨著汽車停止運動而逐漸停止向前運動。如果碰撞劇烈，乘員向前運動更快，即使系了安全帶，在完全停止運動前，仍會與車內物相碰。如果此時裝在轉向盤或儀表板內的氣囊充氣彈出，它就可以保護乘員減少其與車內物相碰的可能性，更均勻的分散頭、胸的碰撞力，吸收乘員的運動能量，從而起到補充安全帶效果的作用。除了安全帶和安全氣囊外汽車被動安全技術還包括汽車保險杠、汽車安全玻璃、安全車身、乘員頭頸保護系統(tǒng)（WHIPS）等。這些對提高汽車行駛的安全性能都有著非常重要的貢獻。