第一篇：外文翻譯-變速器設計

汽車變速器設計

----------外文翻譯

我們知道，汽車發動機在一定的轉速下能夠達到最好的狀態，此時發出的功率比較大，燃油經濟性也比較好。因此，我們希望發動機總是在最好的狀態下工作。但是，汽車在使用的時候需要有不同的速度，這樣就產生了矛盾。這個矛盾要通過變速器來解決。

汽車變速器的作用用一句話概括，就叫做變速變扭，即增速減扭或減速增扭。為什么減速可以增扭，而增速又要減扭呢？設發動機輸出的功率不變，功率可以表示為 N = wT，其中w是轉動的角速度，T是扭距。當N固定的時候，w與T是成反比的。所以增速必減扭，減速必增扭。汽車變速器齒輪傳動就根據變速變扭的原理，分成各個檔位對應不同的傳動比，以適應不同的運行狀況。

一般的手動變速器內設置輸入軸、中間軸和輸出軸，又稱三軸式，另外還有倒檔軸。三軸式是變速器的主體結構，輸入軸的轉速也就是發動機的轉速，輸出軸轉速則是中間軸與輸出軸之間不同齒輪嚙合所產生的轉速。不同的齒輪嚙合就有不同的傳動比，也就有了不同的轉速。例如鄭州日產ZN6481W2G型SUV車手動變速器，它的傳動比分別是：1檔3.704:１；2檔2.202:1；3檔1.414:1；4檔1:1；5檔（超速檔）0.802:1。

當汽車啟動司機選擇1檔時，撥叉將1/2檔同步器向后接合1檔齒輪并將它鎖定輸出軸上，動力經輸入軸、中間軸和輸出軸上的1檔齒輪，1檔齒輪帶動輸出軸，輸出軸將動力傳遞到傳動軸上（紅色箭頭）。典型1檔變速齒輪傳動比是3:1,也就是說輸入軸轉3圈，輸出軸轉1圈。

當汽車增速司機選擇2檔時，撥叉將1/2檔同步器與1檔分離后接合2檔齒輪并鎖定輸出軸上，動力傳遞路線相似，所不同的是輸出軸上的1檔齒輪換成2檔齒輪帶動輸出軸。典型2檔變速齒輪傳動比是2.2:1，輸入軸轉2.2圈，輸出軸轉1圈，比1檔轉速增加，扭矩降低。

當汽車加油增速司機選擇3檔時，撥叉使1/2檔同步器回到空檔位置，又使3/4檔同步器移動直至將3檔齒輪鎖定在輸出軸上，使動力可以從軸入軸—中間軸—輸出軸上的3檔變速齒輪，通過3檔變速齒輪帶動輸出軸。典型3檔傳動比是1.7:1，輸入軸轉1.7圈，輸出軸轉1圈，是進一步的增速。

當汽車加油增速司機選擇4檔時，撥叉將3/4檔同步器脫離3檔齒輪直接與輸入軸主動齒輪接合，動力直接從輸入軸傳遞到輸出軸，此時傳動比1:1，即輸出軸與輸入軸轉速一樣。由于動力不經中間軸，又稱直接檔，該檔傳動比的傳動效率最高。汽車多數運行時間都用直接檔以達到最好的燃油經濟性。

換檔時要先進入空檔，變速器處于空檔時變速齒輪沒有鎖定在輸出軸上，它們不能帶動輸出軸轉動，沒有動力輸出。

一般汽車手動變速器傳動比主要分上述1－4檔，通常設計者首先確定最低（1檔）與最高（4檔）傳動比后，中間各檔傳動比一般按等比級數分配。另外，還有倒檔和超速檔，超速檔又稱為5檔。

當汽車要加速超過同向汽車時司機選擇5檔，典型5檔傳動比是0.87:1，也就是用大齒輪帶動小齒輪，當主動齒輪轉0.87圈時，被動齒輪已經轉完1圈了。

倒檔時輸出軸要向相反方向旋轉。如果一對齒輪嚙合時大家反向旋轉，中間加上一個齒輪就會變成同向旋轉。利用這個原理，倒檔就要添加一個齒輪做“媒介”，將軸的轉動方向調轉，因此就有了一根倒檔軸。倒檔軸獨立裝在變速器殼內，與中間軸平行，當軸上齒輪分別與中間軸齒輪和輸出軸齒輪嚙合時，輸出

軸轉向會相反。

通常倒檔用的同步器也控制5檔的接合，所以5檔與倒檔位置是在同一側的。由于有中間齒輪，一般變速器倒檔傳動比大于1檔傳動比，增扭大，有些汽車遇到陡坡用前進檔上不去就用倒檔開上去。

從駕駛平順性考慮，變速器檔位越多越好，檔位多相鄰檔間的傳動比的比值變化小，換檔容易而且平順。但檔位多的缺點就是變速器構造復雜，體積大，現在輕型汽車變速器一般是4－5檔。同時，變速器傳動比都不是整數，而是都帶小數點的，這是因為嚙合齒輪的齒數不是整倍數所致，兩齒輪齒數是整倍數就會導致兩齒輪嚙合面磨損不均勻，使得輪齒表面質量產生較大的差異。

手動變速器與同步器

手動變速器是最常見的變速器，簡稱MT。它的基本構造用一句話概括，就是兩軸一中軸，即指輸入軸、軸出軸和中間軸，它們構成了變速器的主體，當然還有一根倒檔軸。手動變速器又稱手動齒輪式變速器，含有可以在軸向滑動的齒輪，通過不同齒輪的嚙合達到變速變扭目的。典型的手動變速器結構及原理如下。

輸入軸也稱第一軸，它的前端花鍵直接與離合器從動盤的花鍵套配合，從而傳遞由發動機過來的扭矩。第一軸上的齒輪與中間軸齒輪常嚙合，只要軸入軸一轉，中間軸及其上的齒輪也隨之轉動。中間軸也稱副軸，軸上固連多個大小不等的齒輪。輸出軸又稱第二軸，軸上套有各前進檔齒輪，可隨時在操縱裝置的作用下與中間軸的對應齒輪嚙合，從而改變本身的轉速及扭矩。輸出軸的尾端有花鍵與傳動軸相聯，通過傳動軸將扭矩傳送到驅動橋減速器。

由此可知，變速器前進檔位的驅動路徑是：輸入軸常嚙齒輪－中間軸常嚙齒輪－中間軸對應齒輪－第二軸對應齒輪。倒車軸上的齒輪也可以由操縱裝置撥動，在軸上移動，與中間軸齒輪和輸出軸齒輪嚙合,以相反的旋轉方向輸出。

多數汽車都有5個前進檔和一個倒檔，每個檔位有一定的傳動比，多數檔位傳動比大于1，第4檔傳動比為1，稱為直接檔，而傳動比小于1的第5檔稱為加速檔。空檔時輸出軸的齒輪處于非嚙合位置，無法接受動力傳輸。

由于變速器輸入軸與輸出軸以各自的速度旋轉，變換檔位時合存在一個“同步”問題。兩個旋轉速度不一樣齒輪強行嚙合必然會發生沖擊碰撞，損壞齒輪。因此，舊式變速器的換檔要采用“兩腳離合”的方式，升檔在空檔位置停留片刻，減檔要在空檔位置加油門，以減少齒輪的轉速差。但這個操作比較復雜，難以掌握精確。因此設計師創造出“同步器”，通過同步器使將要嚙合的齒輪達到一致的轉速而順利嚙合。

目前全同步式變速器上采用的是慣性同步器，它主要由接合套、同步鎖環等組成，它的特點是依靠摩擦作用實現同步。接合套、同步鎖環和待接合齒輪的齒圈上均有倒角（鎖止角），同步鎖環的內錐面與待接合齒輪齒圈外錐面接觸產生摩擦。鎖止角與錐面在設計時已作了適當選擇，錐面摩擦使得待嚙合的齒套與齒圈迅速同步，同時又會產生一種鎖止作用，防止齒輪在同步前進行嚙合。當同步鎖環內錐面與待接合齒輪齒圈外錐面接觸后，在摩擦力矩的作用下齒輪轉速迅速降低（或升高）到與同步鎖環轉速相等，兩者同步旋轉，齒輪相對于同步鎖環的轉

速為零，因而慣性力矩也同時消失，這時在作用力的推動下，接合套不受阻礙地與同步鎖環齒圈接合，并進一步與待接合齒輪的齒圈接合而完成換檔過程

自動變速器

自動變速器的選擋桿相當于手動變速器的變速桿，一般有以下幾個擋位：P(停車)、R(倒擋)、N(空擋)、D(前進)、S(or2，即為2速擋)、L(or1，即為1速擋)。這幾個擋位的正確使用對于駕駛自動變速器汽車的人來說尤其重要，下面就讓我們一起來熟悉一下自動變速器各擋位的使用要領。

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●P(停車擋)的使用

發動機運轉時只要選擋桿在行駛位置上，自動變速器汽車就很容易地行走。而停放時，選擋桿必須扳入P位，從而通過變速器內部的停車制動裝置將輸出軸鎖住，并拉緊手制動，防止汽車移動。

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●R(倒擋)的使用

R位為倒擋，使用中要切記，自動變速器汽車不像手動變速器汽車那樣能夠使用半聯動，故在倒車時要特別注意加速踏板的控制。

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●N(空擋)的使用

N位相當于空擋，可在起動時或拖車時使用。在等待信號或堵車時常常將選擋桿保持在D位，同時踩下制動。若時間很短，這樣做是允許的，但若停止時間長時最好換入N位，并拉緊手制動。因為選擋桿在行駛位置上，自動變速器汽車一般都有微弱的行駛趨勢，長時間踩住制動等于強行制止這種趨勢，使得變速器油溫升高，油液容易變質。尤其在空調器工作、發動機怠速較高的情況下更為不利。有些駕駛員為了節油，在高速行駛或下坡時將選擋桿扳到N位滑行，這很容易燒壞變速器，因為這時變速器輸出軸轉速很高，而發動機卻在怠速運轉，油泵供油不足，潤滑狀況惡化，易燒壞變速器。

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●D(前進擋)的使用

正常行駛時將選擋桿放在D位，汽車可在1～4擋(或3擋)之間自動換擋。D位是最常用的行駛位置。需要掌握的是：由于自動變速器是根據油門大小與車速高低來確定擋位的，所以加速踏板操作方法不同，換擋時的車速也不相同。如果起步時迅速將加速踏板踩下，升擋晚，加速能力強，到一定車速后，再將加速踏板很快松開，汽車就能立即升擋，這樣發動機噪聲小，舒適性好。

D位的另一個特點是強制低擋，便于高速時超車，在D位行駛中迅速將加速踏板踩到底，接通強制低擋開關就能自動減擋，汽車很快加速，超車之后松

開加速踏板又可自動升擋。

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●S、L位低擋的使用

自動變速器在S位或L位上處于低擋范圍，可以在坡道等情況下使用。下坡時換入S位或L位能充分利用發動機制動，避免車輪制動器過熱，導致制動效能下降。但是從D位換入S位或L位時，車速不能高于相應的升擋車速，否則發動機會強烈振動，使變速器油溫急劇上升，甚至會損壞變速器。

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另外在雨霧天氣時，若路面附著條件差，可以換入S位或L位，固定在某一低擋行駛，不要使用能自動換擋的位置，以免汽車打滑。同時必須牢記，打滑時可將選擋桿推入N位，切斷發動機的動力，以保證行車安全。

原文：

Transmission design

As we all know,automobile engine to a certain speed can be achieved under the best conditions, when compared issued by the power, fuel economy is relatively good.Therefore, we hope that the engine is always in the best of conditions to work under.However, the use of motor vehicles need to have different speeds, thus creating a conflict.Transmission through this conflict to resolve.Automotive Transmission role sum up in one sentence, called variable speed twisting, twisting or slow down the growth rate by increasing torsional.Why can slow down by twisting, and the growth rate but also by twisting? For the same engine power output, power can be expressed as N = wT, where w is the angular velocity of rotation, and T Niuju.When N fixed, w and T is inversely proportional to the.Therefore, the growth rate will reduce twisting, twisting slowdown will increase.Automotive Transmission speed gear based on the principle of variable twisted into various stalls of different transmission ratio corresponding to adapt to different operational conditions.General to set up a manual gearbox input shaft, intermediate shaft and output shaft, also known as the three-axis, as well as Daodang axis.Three-axis is the main transmission structure, input shaft speed is the speed of the engine, the output shaft speed is the intermediate shaft and output shaft gear meshing between different from the speed.Different gears are different transmission ratio, and will have a different speed.For example Zhengzhourichan ZN6481W2G manual transmission car-SUV, its transmission ratio are: 1 File 3.704:1;stalls 2.202:1;stalls 1.414:1;stalls 1:1 5 stalls(speeding file)0.802: 1.When drivers choose a launch vehicle stalls, Plectrum will be 1 / 2 file synchronization engagement with a back stall gear and output shaft lock it, the power input shaft, intermediate shaft and output shaft gear of a stall, a stall the output shaft gear driven, and the output shaft power will be transmitted to the drive shaft(red arrow).A typical stall Biansuchilun transmission ratio is 3:1, that is to say three laps to the input shaft and output shaft to a circle.When the growth rate of car drivers choose two stalls, Plectrum will be 1 / 2-file synchronization and file a joint separation after 2 stall and lock the output shaft gear, power transmission line similar, the difference is that the output shaft gear of a stall 2 stall replaced by the output shaft gear driven.2 stall Biansuchilun typical transmission ratio is 2.2:1, 2.2 laps to the input shaft and output shaft to a circle than a stall speed increase, lower torque.When refueling vehicle drivers growth stalls option 3, Plectrum to 1 / 2 back to the free file-synchronization position, and also allows the 3 / 4 file synchronization Mobile stall until 3 in the output shaft gear lock, power can be into the shaft axisthe output shaft of the three stalls Biansuchilun, led through three stalls Biansuchilun output shaft.3 stalls typical transmission ratio is 1.7:1, 1.7 laps to the input shaft and output shaft to a circle is further growth.When car drivers Option 4 refueling growth stalls, Plectrum will be 3 / 4 from the 3-file synchronization stall gear directly with the input shaft gear joint initiative, and power transmission directly from the input shaft to the output shaft, the transmission ratio at 1:1, that the input shaft and output shaft speed the same.The driving force without intermediate shaft, also known as direct file, the file transmission than the

maximum transmission efficiency.Most cars run-time files are used directly to achieve the best fuel economy.Shift into the first interval when, in a free transmission when Biansuchilun output shaft is not locked in, they can not rotate the output shaft driven, not power output.General automotive manual transmission than the main 1-4 stalls, usually the first designers to determine the minimum(one stall)and maximum(4 files)transmission ratio, the middle stall drive by geometric progression than the general distribution.In addition, there are stalls Daodang and speeding, speeding file is also known as the five stalls.When the car to accelerate to more than car drivers with the choice of five stalls, and a typical five-transmission ratio is 0.87:1, which is driven by a pinion gear, the gear when the initiative to 0.87 zone, passive gear have been transferred to a circle of the End.Dao Dang, the opposite direction to the output shaft rotation.If one pair of meshing gears when we reverse rotation, with a middle gear, it will become the same to the rotation.Use of this principle, we should add a gear Daodang the “media” will be rotational direction reversed, it will have a Daodang axis.Daodang installed in the transmission shaft independent crust, and the intermediate shaft parallel axis gear with the intermediate shaft and output shaft gear meshing gears, will be contrary to the output shaft.Daodang usually used for the synchronization control also joins five stalls, stalls and Daodang 5 position in the same side.As a middle gear, the general transmission Daodang transmission ratio greater than 1 file transmission ratio, by twisting, steep slope with some vehicles encountered on the progress stalls falters with a Daodang boost.Ride from the driver of the considerations, better transmission stall, stall adjacent stall more than the transmission changes the ratio of small, and easy to shift smoothly.However, the shortcomings of the stalls is more transmission structure is complicated, bulky, light vehicle transmission is generally 4-5 stalls.At the same time, transmission ratio is not integral, but with all of the decimal point, it is because of the gear teeth meshing is not caused by the whole multiples of two gear teeth can lead to the whole multiples of two meshing gears of uneven wear, making the tooth surface quality have a greater difference.Manual transmission and synchronizer

Manual transmission is the most common transmission, or MT.Its basic structure sum up in one sentence, is a two-axle shaft, where input shaft, the shaft axis and intermediate shaft, which constitute the main body of the transmission and, of course, a Daodang axis.Manual transmission known as manual gear transmission, which can be in the axial sliding gears, the gears meshing different variable speed reached twisting purpose.Typical manual transmission structure and principles are as follows.Input shaft also said that the first axis, and its front-end Spline driven directly with the clutch disc sets with the Spline, by the transfer of torque from the engine.The first axis of the intermediate shaft and gears meshing gears often, as long as the shaft axis to a turn, the intermediate shaft and gear also will be rotating.Vice also said intermediate shaft axis, the axis-even more than the size gear.Also known as the second output shaft axis, the axis of various sets of gear stall progress can be manipulated at any time in the

role of the device and the corresponding intermediate shaft gear meshing, thus changing its speed and torque.With the end of the output shaft spline associated with the drive shaft through the drive shaft torque transmitted to the drive axle reducer.Thus, progress stalls drive transmission path is: input shaft gear often rodentscorresponding intermediate shaft gear-the second axis corresponding gear.Reversing the gear shaft can be manipulated by the device pick in the axis movement, and the intermediate shaft and output shaft gear meshing gears, to the contrary to the direction of rotation output.Most cars have five stalls and a Daodang forward, a certain degree of each stall transmission ratio, the majority of stalls transmission ratio greater than 1, 4 file transmission ratio of 1, known as direct stalls, and transmission ratio is less than 1 No.5 stall called accelerated stall.Free at the output shaft gear in a position of non-engagement, unacceptable power transmission.The transmission input shaft and output shaft rotational speed to their own, transform a stall when there is a “synchronous”.Two different rotational speed gear meshing force will impact the collision occurred, damage gear.Therefore, the old transmission shift to a “feet-off” approach, or stall on the location of the free stay for a while by stalls in the free position refueling doors, in order to reduce the speed differential gear.However, this operation is relatively more complicated and difficult to grasp accurate.So designers create a “synchronized,” and allows synchronization through the meshing of gears to be consistent speed and smooth meshing.At present Synchronous Transmission is based on the synchronization of inertia, mainly from joint sets, synchronous lock ring, and so on, it is characterized by friction on the role of synchronization.Splice sets Genlock engagement ring gear and the ring gear when it had Chamfer(Lock angle), Genlock within the cone ring gear engagement with the question of cone ring gear contact friction.Lock and cone angle has been made in the design of an appropriate choice to be made friction cone of the teeth meshing with the ring gear quickly sets pace at the same time will have a Lock role and to prevent the gears meshing in sync before.When synchronization lock cone ring gear engagement with the question of cone ring gear after contact in the effects of friction torque gear speed quickly lower(or higher)with the same speed synchronous lock ring, the two synchronous rotation of the gear Genlock Central zero speed, thus moment of inertia also disappear, then in force under the impetus of engagement sets unhindered and synchronization lock ring gear engagement, and further engagement with the question of gear engagement and the completion Gear Shift Process.The automatic gearbox The automatic gearbox chooses to block the pole the equal to moving the stick shift of the gearbox, having generally below several blocks:P(parking), R(pour to block), N(get empty to block), D(go forward), S(or2, namely for 2 block soon), L.(or1, namely for 1 block soon)This several an usage for blocking a right usages coming driver the automatic gearbox is automotive of person to say particularly important, underneath let us very much familiar with once automatic gearbox eachly blockings main theme.The usage of the P(the parking blocks)The launches the luck turns as long as choose to block the pole in driving the position, automatic gearbox car run about very easily.But park, choose to block the pole

must pull into of P, from but pass the internal parking system in gearbox moves the device will output the stalk lock lives, combining to tense the hand system move, preventing the car ambulation.The usage of the R(pour to block)R a control for is pouring blocking, using inside wanting slicing recording, automatic gearbox car unlike moving gearbox car so can using half moving, so while reversing the car wanting special attention accelerating pedal.The usage of the N(get empty to block)The N is equal to get empty to block, can while starting or hour of trailer usage.At wait for the signal or block up the car will often often choose to block the pole keeps in the of D, trampling at the same time the next system move.If time is very short, do like this is an admission of, but if stop the time long time had better change into of N, combine to tense the hand system moves.Because choose to block the pole in driving the position, the automatic gearbox car has generally and all to drive the trend faintly, long hours trample the system move same as a deterrent this kind of trend, make gearbox oil gone up, the oil liquid changes in character easily.Particularly in the air condition machine work, launch the soon higher circumstance in machine bottom more disadvantageous.Some pilots for the sake of stanza oil, at made good time or go down slope will choose to block the pole pull the of N skids, this burn the bad gearbox very easily, launching the machine to revolves soon in the however because the gearbox outputs at this time the stalk turns soon very high， the oil pump provides the oil shortage, lubricating the condition worsen, burn the bad gearbox easily.

The usage of the D(go forward to block)Will choose to block when is normal to drive the pole put in the of D, car can at 1 ～ 4 block(or 3 block)its change to block automatically.The of D drives the position most in common usely.What demand control is:Because the automatic gearbox is soon high and low with car to come to make sure to block according to the accelerator size a, so accelerate the pedal operation method is different, changing to block the hour of the car is soon too not same alike.If start hour quick accelerate the pedal tramples the bottom, rising to block the night, accelerating the ability is strong, arriving certain car soon behind, then will accelerate the pedal loosen to open very quickly, car can rise to block immediately, launch like this the machine voice is small, comfortable good.The another characteristics of the D is a compulsory low blocking, easy to high speed the hour overtakes a car, will accelerate quickly in of D drove the pedal trample after all, connect the compulsory low fend off the pass and then can reduce to block automatically, the car accelerates very quickly, after overtaking a car loosen to open the pedal of acceleration to can rise to block automatically again.The usage of the S, of L low the usage that block The automatic gearbox in in is placed in the low blocking the scope on of S or of Ls, can usage under an etc.circumstance.It change to can make use of to launch well into of S or of Ls the mechanism move, avoiding the car wheel system move the machine over hot, cause the system move the effect descent while going down slope.But change into from the of D of S or of L, car soon can't higher than rise to block the car homologously soon, otherwise strong vibration in opportunity to launch, make gearbox oil hoicked, even will damage the gearbox.The is another at rain fog weather hour, if the road adheres to the term bad, can change into a position for or of L, fixing at somely first lowly blocking driving, doing not use can automatically changing blocking, in order to prevent the car beats slippery.Must keep firmly in mind at the same time, beat the slippery hour can will choose to block the pole pushes into a motive for, cutting off launching machine, toing guarantee a car the safety.

第二篇：變速器設計-外文翻譯

Dynamic Modeling of Vehicle Gearbox for Early Detection of Localized Tooth Defect

Helwan University ABSTRACT Dynamic modeling of the gear vibration is a useful tool to study the vibration response of a geared system under various gear parameters and operating conditions.An improved understanding of vibration signal is required for early detection of incipient gear failure to achieve high reliability.However, the aim of this work is to make use of a 6-degree-of-freedom gear dynamic model including localized tooth defect for early detection of gear failure.The model consists of a gear pair, two shafts, two inertias representing load and prime mover and bearings.The model incorporates the effects of time-varying mesh stiffness and damping, backlash, excitation due to gear errors and modifications.The results indicate that the simulated signal shows that as the defect size increases the amplitude of the acceleration signal increases.The crest factor and kurtosis values of the simulated signal increase as the fault increases.Though the crest factor and kurtosis values give similar trends, kurtosis is a better indicator as compared to crest factor.KEYWORDS：Vibration acceleration, system modeling, Crest Factor, Kurtosis value, defect size, gear meshing, pinion, gear NOMENCLATURE JD，J1，J2，JL

Drive motor, pinion, gear, and load mass moment of inertia

Nagwa Abd-elhalim, Nabil Hammed, Magdy Abdel-hady，Shawki Abouel-Seoud and Eid S.Mohamed

replacement decision in a suitable time.m1，mMasses of pinion and gear.TD

Driving motor torque.TL

Load torque.第 1 頁

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TF1，TFFriction torque.C1，C2

Viscous damping coefficient of pinion and gear bearing.Cm

Gear mesh damping.Gear mesh stiffness.Km

K1，K2

Pinion and gear shaft stiffness.4?

The variance square.N

The number of samples.f

The defect width in face direction.Unit width Hertzian stiffness.Kh?D，?1，?2，?L Angular displacement of drive motor, pinion, gear and load.??D，??1，??2，??L Angular velocity of drive motor, pinion, gear and load.??，???，???，??? Angular acceleration of drive motor, pinion, gear and load.?D12LINTRODUCTION Much of the past research in the dynamic modeling area has concluded that an essential solution to the problem is to use a comprehensive computer modeling and simulation tool to aid the transmission design and experiments.These have been two major obstacles to such an approach:(1)Progress in understanding of the basic gear rattle phenomenon has been limited and slow.This is because the engine-clutch-transmission system involves some strong nonlinearities including gear backlash, multi-valued springs, dry friction, hysteresis, and the like.(2)The gear rattle is a system problem and not only problem of gear teeth.Even through the research and industrial community has discussed the difficulties in varies stages of the problem, yet no thorough frame work covering the entire investigation process of such problem currently exists.This is largely due o the complexity of the power train system, which

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may make a computer analysis tool inefficient, in particularly when many different elements and clearances are encountered(e.g., gears, bearings, splines, synchronizers, and clutch)[1-3].A comprehensive review of mathematical models used in gear dynamics, published before 1986, has been presented by [4].In this review, gear dynamic models without defects have been discussed.In the past few years, researchers have been working on the gear dynamic models which include defects like pitting, spalling, crack and broken tooth.A single-degree-of-freedom model is used which include the e4ffects of variable mesh stiffness, damping, gear errors, profile modifications and backlash.The effect of time-varying meshing damping is also included in this case, The solution is obtained by using the harmonic balance methods.A method of calculated the optimum profile modification has been proposed in order to obtain a zero vibration of the gear pair [5-7].They also proposed a linear approximate equation to mode the gear pair by using a single-degree-of freedom model Gear rattle vibration is a undesirable vibration for passenger cars and light trucks equipped with manual transmissions.Unlike automatic transmissions, manual transmission do not have the high viscous damping inherent to a hydrodynamic torque converter to suppress the impacting of gear teeth oscillating through their gear backlash.Therefore a significant level of vibration an be produced by the gear rattle and transmitted both inside the passenger compartment and outside the vehicle.Gear rattle, idle shake, and other vibration generated in the automobile driveline have become an important concern to automobile manufactures in their pursuit of an increased level of perception of high vibration quality.The torsional vibration o driveline is a major source of gear rattle vibration.The manual transmission produces gear rattle by the impacting of gear oscillating through their gear backlash.The impact collisions are transmitted to the transmission housing via shafts and bearings [8].The gear pair dynamic models including defects have been done by [9].The study

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suggests that little work has been done on modeling of gear vibration with defect and an accurate analytical procedure to predict gear vibrations in the presence of local tooth fault has yet to be developed.However, the purpose of this paper is to develop a multidegree-of-freedom nonlinear model for a gear pair that can be used to study the effect of lateral-torsional vibration coupling on vibration response in the presence of localized tooth defect.A typical fault signal is assumed to be impulsive in nature because of the way it is generated.The simulation artificially introduced pitting in gears in multi-stage automotive transmission gearbox at different operation conditions(load, speed, etc).The processing of simulated and experimental signals is also introduced.SIGNAL-PROCESSING TECHNIQUE Among various signal-processing techniques, crest factor and kurtosis analysis have been used for analyzing the whole vibration signal for the early detection of fault.In this section, crest factor and kurtosis value have been explained.MATHEMATICAL MODEL FORMULATION

Helical gears are almost always used in automotive transmissions.The meshing stiffness of a helical tooth pair is time-varying [10], and was modeled as a series of suggested spur gears so that the simulation techniques for spur gears can be applied.where M is Module(mm), b is Face width(mm), ? is pressure angle(deg), ? is helix angle(deg)and D1 is pitch diameter(mm).Fig.2 shows the equivalent gear system in the first gear-shift, where the main parameters for the gear system of Fiat-131 gearbox and the equivalent gear system in the first gear-shift are also shown in the figures.第 4 頁

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汽車變速箱動態建模輪齒局部缺陷的早期檢測

Nagwa Abd-elhalim, Nabil Hammed, Magdy Abdel-hady，Shawki Abouel-Seoud and Eid S.Mohamed

阿勒旺大學

摘要

在研究齒輪系統中各種齒輪參數的振動響應和操作條件時，齒輪振動的動態建模是一個非常有用的工具。對早期的齒輪檢測提出了一種改進理解的振動信號，但還沒達到高的可靠性。但是，這項工作的目的是利用一個6自由度的齒輪動力學模型對齒輪輪齒缺陷故障的早期檢測。該模型包括一對齒輪副、兩個軸、兩個慣性負載、動力傳動裝置和軸承。由于齒輪的誤差和變動，該模型被采用時受到時變嚙合剛度、阻尼、反彈和勵磁的影響。模擬信號顯示的結果表明，隨著缺陷尺寸的增加加速度信號的振幅增加。模擬信號的波峰因素和峰值隨著缺陷的增加而增加。雖然波峰因素和峰值做同樣的趨勢，但和波峰因素相比峰值是一個比較好的指標。關鍵詞：振動加速度、系統建模、波峰因素、峰值、缺陷大小、齒輪嚙合、齒輪 專業術語

JD，J1，J2，JL

驅動電機、小齒輪、大齒輪和負載在一定時間內的慣性矩 m1，m

1大齒輪、小齒輪的模數 TD

發動機驅動轉矩 TL

負載力矩 TF1，TF摩擦力矩

C1，C2

齒輪、軸承的粘滯阻尼系數

Cm

齒輪嚙合阻尼

齒輪嚙合剛度 Km

K1，K齒輪、齒輪軸的剛度

?

平方差

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N

樣本數量

f

寬度方向的缺陷

單位寬度的剛度 Kh?D，?1，?2，?L

驅動電機、小齒輪、大齒輪和負載的角位移 ??D，??1，??2，??L

驅動電機、小齒輪、大齒輪和負載的角速度

??，???，???，???

驅動電機、小齒輪、大齒輪和負載的角加速度 ?D12L引言

在大多數過去的動態建模研究領域中，解決問題的重要辦法是全面使用計算機建模和仿真工具來輔助變速器的設計和實驗。這種方法有兩種主要的障礙：（1）對齒輪傳動中噪聲基本認識的進展是有限的和緩慢的。這是因為發動機離合器傳動系統中包括齒輪側隙、多值彈簧、非線性滯后等等。（2）齒輪發出的噪聲是一個系統問題，并不是齒輪的唯一問題。既使是工業研究領域已經討論了這個問題在不同階段所出現的不同問題，但并沒有徹底覆蓋工作的框架，整個研究過程中的問題依然存在。這主要是由于列車電力系統的復雜性，可能導致你的計算機的分析工具效率不高，尤其是工作中遇到許多不同的因素和間隙（例如：齒輪、軸承、花鍵、同步器和離合器）。

在1986年出版之前，對齒輪動力學中提出的齒輪動態建模進行了審查。這次審查中，對不存在齒輪缺陷的齒輪動力學模型進行了討論。在過去的幾年里，研究人員對齒輪的動態模型缺陷進行了研究，其中包括點蝕、剝落、裂縫和齒輪折斷等。

單自由度系統模型中，對嚙合剛度的影響包括4個方面的因素，阻尼、齒輪誤差、輪廓變動和齒側間隙，時變嚙合阻尼效應也包含在這種情況中。解決問題的方法是利用諧波平衡的方法。為了實現齒輪副的零振動，提出了一種最優化的計算方法。他們還利用齒輪副單自由度模型提出了一個近似的線性方程模型。

齒輪噪聲振動是轎車和輕型貨車手動變速箱中的不良振動。不同于自動變速箱的是，手動變速箱沒有一個固有的高粘性阻尼液力變矩器以制止通過齒輪側隙造成的齒輪擺動的影響。因此，無論是在車廂內外由齒輪振動和傳動產生的噪聲，對車

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輛振動的影響都非常大。隨著人們對汽車高性能振動的追求，齒輪松動、振動以及其他汽車傳動系產生的噪聲已成為人們關注的重點。傳動系統中的扭轉振動是齒輪振動的一種主要噪聲來源。手動變速箱產生的齒輪噪聲是由于齒輪受到齒輪間隙振動的影響。通過軸和軸承把碰撞產生的影響傳輸到變速箱殼體。

對齒輪副的動態模型缺陷的研究結果表明，對齒輪副動態模型缺陷已做了大量工作，用準確的分析方法對齒輪振動的檢測在當時輪齒故障方面還沒得到發展。然而，本研究的目的是建立一個多自由度非線性模型用于研究，結果表明輪齒局部缺陷的扭轉振動是耦合振動的響應。由于他的產生一個典型的故障信號被假設為自然的脈沖信號。在不同操作條件下（負荷、轉速等），模擬人工對多級汽車變速器齒輪缺陷進行了介紹。同時也對信號的仿真和實驗處理進行了介紹。信號處理技術

在各種各樣的信號處理技術中，波峰因素、峰值已用于分析整個振動信號的早期故障。在本節中，波峰因素和峰值已被解釋。數學模型

汽車變速器中的齒輪大都是斜齒圓柱齒輪。被視為一系列齒輪仿真技術適用于螺旋狀的輪齒時變嚙合剛度。式中m是模數(毫米),b齒面寬(毫米),?是壓力角(度),?是螺旋角(度)，D1是直徑(毫米)。圖2的數據顯示了等效齒輪系統在齒輪變動中變速箱齒輪系統的主要參數。

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第三篇：外文翻譯

當今時代是一個自動化時代，交通燈控制等很多行業的設備都與計算機密切相關。因此，一個好的交通燈控制系統，將給道路擁擠，違章控制等方面給予技術革新。隨著大規模集成電路及計算機技術的迅速發展，以及人工智能在控制技術方面的廣泛運用，智能設備有了很大的發展，是現代科技發展的主流方向。本文介紹了一個智能交通的系統的設計。該智能交通燈控制系統可以實現的功能有：對某市區的四個主要交通路口進行控制：個路口有固定的工作周期，并且在道路擁擠時中控制中心能改變其周期：對路口違章的機動車能夠即時拍照，并提取車牌號。在世界范圍內，一個以微電子技術，計算機和通信技術為先導的，一信息技術和信息產業為中心的信息革命方興未艾。而計算機技術怎樣 與實際應用更有效的結合并有效的發揮其作用是科學界最熱門的話題，也是當今計算機應用中空前活躍的領域。本文主要從單片機的應用上來實現十字路口交通燈智能化的管理，用以控制過往車輛的正常運作。

研究交通的目的是為了優化運輸，人流以及貨流。由于道路使用者的不斷增加，現有資源和基礎設施有限，智能交通控制將成為一個非常重要的課題。但是，智能交通控制的應用還存在局限性。例如避免交通擁堵被認為是對環境和經濟都有利的，但改善交通流也可能導致需求增加。交通仿真有幾個不同的模型。在研究中，我們著重于微觀模型，該模型能模仿單獨車輛的行為，從而模仿動態的車輛組。

由于低效率的交通控制，汽車在城市交通中都經歷過長時間的行進。采用先進的傳感器和智能優化算法來優化交通燈控制系統，將會是非常有益的。優化交通燈開關，增加道路容量和流量，可以防止交通堵塞，交通信號燈控制是一個復雜的優化問題和幾種智能算法的融合，如模糊邏輯，進化算法，和聚類算法已經在使用，試圖解決這一問題，本文提出一種基于多代理聚類算法控制交通信號燈。

在我們的方法中，聚類算法與道路使用者的價值函數是用來確定每個交通燈的最優決策的，這項決定是基于所有道路使用者站在交通路口累積投票，通過估計每輛車的好處(或收益)來確定綠燈時間增益值與總時間是有差異的，它希望在它往返的時候等待，如果燈是紅色，或者燈是綠色。等待，直到車輛到達目的地，通過有聚類算法的基礎設施，最后經過監測車的監測。

我們對自己的聚類算法模型和其它使用綠燈模擬器的系統做了比較。綠燈模擬器是一個交通模擬器，監控交通流量統計，如平均等待時間，并測試不同的交通燈控制器。結果表明，在擁擠的交通條件下，聚類控制器性能優于其它所有測試的非自適應控制器，我們也測試理論上的平均等待時間，用以選擇車輛通過市區的道路，并表明，道路使用者采用合作學習的方法可避免交通瓶頸。

本文安排如下：第2部分敘述如何建立交通模型，預測交通情況和控制交通。第3部分是就相關問題得出結論。第4部分說明了現在正在進一步研究的事實，并介紹了我們的新思想。

The times is a automation times nowadays,traffic light waits for much the industey equipment to go hand in hand with the computer under the control of.Therefore,a good traffic light controls system,will give road aspect such as being crowded,controlling against rules to give a technical improvement.With the fact that the large-scale integrated circuit and the computer art promptness develop,as well as artificial intelligence broad in the field of control technique applies,intelligence equipment has had very big development,the main current being that modern science and technology develops direction.The main body of a book is designed having introduccd a intelligence traffic light systematically.The function being intelligence traffic light navar’s turn to be able to come true has：The crossing carries out supervisory control on four main traffic of some downtown area;Every crossing has the fixed duty period,charges centrefor being able to change it’s period and in depending on a road when being crowded;The motro vehicle breaking rules and regulations to the crossing is able to take a photo immediately,abstracts and the vehicle shop sign.Within world range ,one uses the microelectronics technology,the computer and the technology communicating by letter are a guide’s,centering on IT and IT industry information revolution is in the ascendant.But,how,computer art applies more effective union and there is an effect’s brought it’s effect into play with reality is the most popular topic of scientific community,is also that computer applications is hit by the unparalleled active field nowadays.The main body of a book is applied up mainly from slicing machine’s only realizing intellectualized administration of crossroads traffic light,use operation in controlling the vehicular traffic regularity.Transportation research has the goal to optimize transportation flow of people and goods.As the number of road users constantly increases, and resources provided by current infras-tructures are limited, intelligent control of traffic will become a very important issue in thefuture.However, some limitations to the usage of intelligent tra?c control exist.Avoidingtraffic jams for example is thought to be beneficial to both environment and economy, butimproved traffic-flow may also lead to an increase in demand [Levinson, 2003].There are several models for traffic simulation.In our research we focus on microscopicmodels that model the behavior of individual vehicles, and thereby can simulate dynam-ics of groups of vehicles.Research has shown that such models yield realistic behavior[Nagel and Schreckenberg, 1992, Wahle and Schreckenberg, 2001].Cars in urban traffic can experience long travel times due to inefficient traffic light con-trol.Optimal control of traffic lights using sophisticated sensors and intelligent optimizationalgorithms might therefore bevery beneficial.Optimization of traffic light switching increasesroad capacity and traffic flow, and can prevent tra?c congestions.Traffic light control is acomplex optimization problem and several intelligent algorithms, such as fuzzy logic, evo-lutionary algorithms, and reinforcement learning(RL)have already been used in attemptsto solve it.In this paper we describe a model-based, multi-agent reinforcement learningalgorithm for controlling traffic lights.In our approach, reinforcement learning [Sutton and Barto, 1998, Kaelbling et al., 1996]with road-user-based value functions [Wiering, 2000] is used to determine optimal decisionsfor each traffic light.The decision is based on a cumulative vote of all road users standingfor a traffic junction, where each car votes using its estimated advantage(or gain)of settingits light to green.The gain-value is the difference between the total time it expects to waitduring the rest of its trip if the light for which it is currently standing is red, and if it is green.The waiting time until cars arrive at their destination is estimated by monitoring cars flowingthrough the infrastructure and using reinforcement learning(RL)algorithms.We compare the performance of our model-based RL method to that of other controllersusing the Green Light District simulator(GLD).GLD is a traffic simulator that allows usto design arbitrary infrastructures and traffic patterns, monitor traffic flow statistics such asaverage waiting times, and test different traffic light controllers.The experimental resultsshow that in crowded traffic, the RL controllers outperform all other tested non-adaptivecontrollers.We also test the use of the learned average waiting times for choosing routes of cars through the city(co-learning), and show that by using co-learning road users can avoidbottlenecks.

第四篇：外文翻譯

設計一個位于十字路口的智能交通燈控制系統

摘要：本文模型使用模糊本體的交通燈控制域，并把它應用到控制孤立十字路口。本文最重要的目的之一是提出一個獨立的可重復使用的交通燈控制模塊。通過這種方式，增加軟件的獨立性和為其他的軟件開發活動如測試和維護，提供了便利。專家對本體論進行手動的開發和評估。此外，交通數據提取和分類路口使用的人工神經網絡的圖像處理算法。根據預定義的XML架構，這種信息轉化為XML實例映射到適合使用模糊推理引擎的模糊規則的模糊本體。把本系統的性能與其他類似的系統性能進行比較。比較結果顯示：在所有的交通條件下，在每個周期中，對每輛車它有低得多的平均延遲時間與其他的控制系統相比。

關鍵詞:模糊本體,智能代理,智能交通系統(ITS),交通信號燈控制(TLC),孤立的十字路口,圖像處理,人工神經網絡

1.引言

作為城市交通增加的結果,道路網絡的能力有限和發展交通工具和方法的技術方面，許多實體，關系，情況和規則已經進入交通燈控制域和轉化成為一個知識領域。這個領域的建模知識幫助交通代理和應用有效地管理關于實時條件下的交通。全面知識建模領域的一個最合適的方法是使用本體概念。“本體論是一個正式的、明確的一個共享的概念化的規范。以前的模型是基本的本體建設的基礎，為下列建立一個共享的語義豐富的知識域。除了本體作為概念化的形式主義的重要性，它有可能超過所代表的數據。這種能力將提高有關性能的決定和其他非智能系統的功能特點。在近年來，本體論上的研究正成為一個新的熱點話題在不同的活動，如人工智能，知識管理，語義網絡，電子商務和幾個其他應用領域。這些領域之一是智能交通系統。一些努力已制成這個通過展示和使用本體檢測交通領域擁塞，管理非城市道路氣象事件，駕駛阿德福—索里系統，共享和整合一個智能交通系統。本文的目的是介紹一個紅綠燈有效控制孤立交叉口這方面的知識重用的控制本體。這種新的辦法適用于智能代理使用知識決策模糊。該系統采用的圖像來自安裝了監控攝像機拍攝的路口。這些圖像處理利用圖像處理算法和神經網絡的方法，然后發送到一個智能代理。第2節中，我們將簡要地解釋了在這項工作中運用的技術包括seman-TIC網絡技術，智能代理技術和交通的回地面光控制方法。在第3節，新的系統架構是基于分層語義網絡架構。第4節介紹交通燈控制的模糊本體的建設。第五節從路口提取的圖像信息解釋。在第6節，智能系統的運作被完整描述，最后在第7節對所提出的方法進行評估，對結論進行闡述。

2.背景

本節說明在這項工作中的應用技術包括語義網絡技術，特別本體和模糊本體。此外，國家的交通燈控制的藝術方法是簡要介紹。2.1.語義網絡技術

語義網絡被定義為當前Wed的延伸，這些網站的信息都給出明確的含義;使電腦與人更好的合作。有幾層語義Web的建議源自伯納斯滯后階段。在此類別中的所有規則如表1所示。圖.4顯示輸出模式的示意圖。本次評選有助于智能系統，以確定下一步的階段測序。

另一種模糊的規則類別涉及估計優化周期時間。這些規則的模糊變量是天氣條件，時間，每天平均車輛擁堵情況。出于這個原因，60個模糊規則被定義了。從氣象研究所取得氣象條件。日期和時間也是在交通專家的知識的基礎上以模糊變量形式預先定義的。圖5顯示日期，時間和周期時間的隸屬函數。當天的參數是在日歷基礎上基于假期和正常的一天與周期時間量的關系預定義的。例如，假期期間的周期時間是較平日少。因此，平日的隸屬度比假期多。

例如一個階段選型的模糊規則如下所述：“如果一個路口的類型是四的方式，平均車輛擁堵低，平均行人擁堵是中等，然后相類型是簡單的兩階段”。此外，為周期時間估計的模糊規則表示如下：“如果天氣條件是晴天，時間是早晨，天是正常的，平均車輛擁堵是低，則周期時間短”。在此類別中的所有規則都列在附錄A。

在此步驟結束時，應該對交通燈邏輯控制的項目的有效性進行評估。此功能是使用專家的意見。評價過程的主要目的是顯示發展的本體和其相關的軟件環境的用處。雖然所有的信息，尤其是交通燈控制規則已提取國際標準和科學交通文學，專家的知識優勢是他們最后的正確性驗證標準。所有模糊規則，包括優化周期時間和相位類型的規則，在這個過程中，準備以調查問卷形式和展現給一些專家包括從德黑蘭警察局交通上校和兩名來自德黑蘭的交通組織工程師。由于德爾菲專家的意見，約有84％的淘汰型規則和優化周期時間的87％被接受。此外，所有交通邏輯控制的元素包括概念，關系，屬性和公理都被這些專家進行了評估和驗證。我們評估邏輯交通控制是基于理論知識的。在這個過程中進行了兩項活動，包括檢查的要求和能力的問題，并在目標應用環境測試本體。由于邏輯交通控制已建成的基礎上，如指定要求優化循環時間，逐步淘汰型，交通的移動和優化綠燈時間，每個階段的序列中，第一項活動是最好的結果。邏輯交通控制滿足所有的交通燈控制的需求，并能回答的能力問題。績效評估機制，可以支持這種說法。在部分實驗結果我們驗證了這一過程。

第五篇：外文翻譯

中原工學院畢業設計（論文）譯文

超聲測距系統設計

原文出處：傳感器文摘 布拉福德：1993年第13頁

摘要：超聲測距系統技校在工業場車輛導航水聲工程等領域都具有了廣泛的應用價值，目前已應用于物理測量，機器人自動導航以及空氣中與水下的目標探測、識別定位等場合，因此，深入研究超聲的探測理論和方法具有重要的實踐意義，為了進一步提高測量的精確度，滿足工程人員對測量精度測距量程和測距儀使用的要求，本文研制了一套基于單片機的使拱式超聲測距系統。關鍵詞：超聲波 測距儀 單片機

1、前言

隨著科技的發展，人們生活水平的提高，城市發展建設加快，城市給排水系統也有較大發展，其狀況不斷改善，但是，由于歷史原因合成時間性的許多不可預見因素，城市給排水系統，特別是排水系統往往落后于城市建設，因此，經常出現開挖已經建設好的建筑設施來改造排水系統的現象。城市污水給人們帶來的困擾，因此箱的排污疏通對大城市給排水系統污水理，人們生活舒適顯得非常重要。而設計研制箱涵排水疏通移動機器人的自動控制系統，保證機器人在箱涵中自由排污疏通，是箱涵排水系統疏通機器人的設計研制的核心部分，控制系統核心部分就是超聲波測儀的研制。因此，設計好的超聲波測距儀就顯得非常重要了。

1.1課題背景

隨著經濟的發展與汽車科學技術的進步，公路交通呈現出行駛高速化、車流密集化和駕駛員非職業化的趨勢。同時，隨著汽車工業的飛速發展，汽車的產量和保有量都在急劇增加。但公路發展、交通管理卻相對落后，導致了交通事故與日劇增，城市里尤其突出。智能交通系統ITS是目前世界上交通運輸科學技術的前沿技術，它在充分發揮現有基礎設施的潛力，提高運輸效率，保障交通安全，緩解交通賭塞，改善城市環境等方面的卓越效能，已得到各國政府的廣泛關注。中國政府也高度重視智能交通系統的研究開發與推廣應用。汽車防撞系統作為ITS 發展的一個基礎，它的成功與否對整個系統有著很大的作用。從傳統上說，汽車的安全可以分為兩個主要研究方向:一是主動式安全技術，即防止事故的發生，該種方式是目前汽車安全研究的最終目的;二是被動式安全技術，即事故發生后的乘員保護。目前汽車安全領域被動安全研究較多，主要從安全氣囊、ABS(防抱死系統)和懸架等方面著手，以保證駕乘人員的安全。從經濟性和安全性兩方面來說，中原工學院畢業設計（論文）譯文

這些被動安全措施是在事故發生時刻對車輛和人員進行保護，有很大的局限性，因而車輛的主動安全研究尤為重要，引出了本文研究的基于單片機的超聲波測距系統。這個系統是一種可向司機預先發出視聽語音信號的探測裝置。它安裝在汽車上，能探測企圖接近車身的行人、車輛或周圍障礙物;能向司機及乘員提前發出即將發生撞車危險的信號，促使司機采取應急措施來應付特殊險情，避免損失。

1.2 課題設計的意義

隨著現代社會工業化程的發展，汽車這一交通工具正為越來越多的人所用，但是隨之而來的問題也顯而易見，那就是隨著車輛的增多，交通事故的頻繁發生，由此導致的人員傷亡和財產損失數目驚人。對于公路交通事故的分析表明，80%以上的車禍事由于駕駛員反應不及所引起的，超過65%的車輛相撞屬于追尾相撞，其余則屬于側面相撞。奔馳汽車公司對各類交通事故的研究表明：若駕駛員能夠提早1S 意識到有事故危險并采取相應的正確措施，則絕大多數的交通事故都可以避免。因此，大力研究開發如汽車防撞裝置等主動式汽車輔助安全裝置，減少駕駛員的負擔和判斷錯誤，對于提高交通安全將起到重要的作用。顯然，此類產品的研究開發具有極大的實現意義和廣闊的應用前景。

1.3超聲波測距在汽車上應用的介紹

超聲波倒車測距儀(俗稱電子眼)是汽車倒車防撞安全輔助裝置，能以聲音或者更為直觀的數字形式動態顯示周圍障礙物的情況。其較早的產品是用蜂鳴器報警，蜂鳴聲越急，表示車輛離障礙物越近。后繼的產品可以顯示車后障礙物離車體的距離。其大多數產品探測范圍在0.4～1.5m，有的產品能達到0.35～2.5m，并有距離顯示、聲響報警、區域警示和方位指示，有些產品還具備開機自檢功能。目前市場上還出現了具有語音報警功能的產品。這些產品存在的主要問題是測量盲區大，報警滯后，未考慮汽車制動時的慣性因素，使駕駛者制動滯后，抗干擾能力不強，誤報也較多。汽車防撞雷達之所以能實現防撞報警功能，主要有超聲波這把無形尺子, 它測量最近障礙物的距離, 并告訴給車主。其實超聲測距原理簡單: 它發射超聲波并接收反射回波, 通過單片機計數器獲得兩者時間差t, 利用公式S=Ct/2計算距離, 其中S為汽車與障礙物之間的距離, C為聲波在介質中的傳播速度。

本文介紹的超聲測距系統共有2只超聲波換能器(俗稱探頭),分別布置在汽車的后左、后右2個位置上。能檢測前進和倒車方向障礙物距離, 通過后視鏡內置的

中原工學院畢業設計（論文）譯文

顯示單元顯示距離和方位, 發出一定的聲響, 起到提示和警戒的作用。系統采用一片STC89C52單片機對兩路超聲波信號進行循環采集。超聲波是指頻率高于20HHZ的機械波。為了以超聲波作為檢測手段，必須產生超生波和接收超聲波。完成這種功能的裝置就是超聲波傳感器，習慣上稱為超聲波換能器或超聲波探頭。超聲波傳感器有發送器和接收器，但一個超聲波傳感器也可具有發送和接收聲波的雙重作用。超聲波傳感器是利用壓電效應的原理將電能和超聲波相互轉化，即在發射超聲波的時候，將電能轉換，發射超聲波；而在收到回波的時候，則將超聲振動轉換成電信號。超聲波測距的原理一般采用渡越時間法。首先測出超聲波從發射到遇到障礙物返回所經歷的時間，再乘以超聲波的速度就得到二倍的聲源與障礙物之間的距離。測量距離的方法有很多種，短距離的可以用尺，遠距離的有激光測距等，超聲波測距適用于高精度的中長距離測量。因為超聲波在標準空氣中的傳播速度為331.45米/秒，由單片機負責計時，單片機使用12.0M晶振，所以此系統的測量精度理論上可以達到毫米級。由于超聲波指向性強，能量消耗緩慢，在介質中傳播距離遠，因而超聲波可以用于距離的測量。利用超聲波檢測距離，設計比較方便，計算處理也較簡單，并且在測量精度方面也能達到要求。超聲波發生器可以分為兩類：一類是用電氣方式產生超聲波，一類是用機械方式產生超聲波。本設計屬于近距離測量，可以采用常用的壓電式超聲波換能器來實現觸發單元。

利用超聲波測距的工作，就可以根據測量發射波與反射波之間的時間間隔，從而達到測量距離的作用。其主要有三種測距方法：

（1）相位檢測法，相位檢測法雖然精度高，但檢測范圍有限；

（2）聲波幅值檢測法，聲波幅值檢測法易受反射波的影響；

（3）渡越時間檢測法，渡越時間檢測法的工作方式簡單，直觀，在硬件控制和軟件設計上都非常容易實現。其原理為：檢測從發射傳感器發射超聲波，經氣體介質傳播到接收傳感器的時間，這個時間就是渡越時間。本設計的超聲波測距就是使用了渡越時間檢測法。在移動車輛中應用的超聲波傳感器，是利用超聲波在空氣中的定向傳播和固體反射特性（縱波），通過接收自身發射的超聲波反射信號，根據超聲波發出及回波接收的時間差和傳播速度，計算傳播距離，從而得到障礙物到車輛的距離。

中原工學院畢業設計（論文）譯文 超聲波測距原理

2.1 壓電式超聲波發生器原理

壓電式超聲波發生器實際上是利用壓電晶體的諧振來工作的。超聲波發生器內部結構，它有兩個壓電晶片和一個共振板。當它的兩極外加脈沖信號，其頻率等于壓電晶片的固有振蕩頻率時，壓電晶片將會發生共振，并帶動共振板振動，便產生超聲波。反之，如果兩極板間未加電壓，當共振板接收到超聲波時，將壓迫壓電晶片做振動，將機械能轉換為電信號，這是它就成為超聲波接收器了。

測量脈沖到達時間的傳統方法是以擁有固定參數的接收信號開端為基礎的。這個信號恰恰選于噪音水平之上，然而脈沖到達時間被定義為脈沖信號剛好超過界限的第一時刻。一個物體的脈沖強度很大程度上取決于這個物體的自然屬性尺寸還有它與傳感器的距離。進一步說，從脈沖起始點到剛好超過界限之間的時間段隨著脈沖的強度而改變。結果，一種錯誤便出現了——兩個擁有不同強度的脈沖在不同時間超過界限卻在同一時刻到達。強度較強的脈沖會比強度較弱的脈沖超過界限的時間早點，因此我們會認為強度較強的脈沖屬于較近的物體。

2.2 超聲波測距原理

超聲波發射器向某一方向發射超聲波，在發射時刻的同時開始計時，超聲波在空氣中傳播，途中碰到障礙物就立即返回來，超聲波接收器收到反射波就立即停止計時。超聲波在空氣中的傳播速度為340m/s，根據計時器記錄的時間t，就可以計算出發射點距離障礙物的距離(s)，即：s=340t/2

中原工學院畢業設計（論文）譯文

3、超聲波測距系統的電路設計

系統的特點是利用單片機控制超聲波的發射和超聲波自發射至接受往返時間的計時，單片機選用C51，經濟易用，且片內有4K的ROM，便于編程。電路的原理如圖1所示。

圖1 電路原理圖

中原工學院畢業設計（論文）譯文

3.1 40kHz脈沖的產生與超聲波發射

測距系統中的超聲波傳感器采用UCM40的壓電陶瓷，它的工作電壓是40kHz的脈沖信號，這由單片機執行下面的程序來產生。puzel：mov 14h，#12h

here： cp1.0；

nop；

nop；

nop；

djnz 14h，here；

Ret

前方測距電路的輸出端接單片機P1.0端口，單片機執行上面的程序后，在P1.0端口輸出一個40khz的脈沖信號，經過三極管T放大，驅動超聲波發射頭UCM40T，發出40khz的脈沖超聲波，且持續發射200ms。右側合作側測距電路的輸入端分別接P1.1和P1.2端口，工作原理和前方測距電路相同。

超聲波發射持續200ms 輸出40kHz方波

3.2 超聲波的接收與處理

接收頭采用與發射頭配對的UCM40R，將超聲波調制脈沖變為電壓信號，經運算放大器ic1a和ic1b兩級放大后加至IC2,。IC2是帶有鎖定環的音頻譯碼集成塊LM567，內部壓控振蕩器的中心頻率f0=1/1.1R8C3，電容C4決定其帶寬。調節R8在發射的載頻上，則LM567輸入信號大于25mv，輸出端8腳由5由高電平躍變為低電平，作為中斷請求信號，送至單片機處理。

前方測距電路的輸出端接至單片機INT0端口，中斷優先級最高，左、右測距電路的輸出通過與門IC3A的輸出接單片機的INT1端口，同時單片機P1.3和P1.4接到IC3A的輸入端，中斷源的識別由程序查詢來處理，中斷優先級為先右后左。部分源程序如下： receive1：push psw

push acc

clr ex1；關中斷源1

jnb p1.1，right;P1.1引腳為0，轉至右側距電路中斷服務程序

jnb p1.2,left;P1.2 引腳為0，轉至左測距中斷電路服務程序 returne：SETB EX1；

開外部中斷1

pop acc

中原工學院畢業設計（論文）譯文

pop psw

reti right：

...；

右測距電路中斷服務程序入口

ajmp return

left：

...；

左測距電路中斷服務程序入口

ajmp return

3.3 計算超聲波傳播時間

在啟動發射電路的同時啟動單片機內部的定時器T0，利用定時器的計數功能，記錄超聲波發射的時間和受到反射波的時間。當收到超聲波反射波時，接受電路輸出端產生一個負跳變，在INT0或INT1端產生一個中斷請求信號，單片機響應外部中斷請求，執行外部中斷服務子程序，讀取時間差，計算距離。其部分源程序如下：

RECEIVEO: PUSH PSW

PUSH ACC CLR EX0;

關外部中斷0 讀取時間值

MOV R7,TH0;MOV R6,TL0 CLR C MOV A,R6 SUBB A,#0BBH;MOV 31H,A;MOV A,R7 SUBB A,#3CH MOV 30H,A SETB EX0;POP ACC

POP PSW

RETI 對于一個平坦的目標，測量距離包括兩個階段：粗糙的測量和精細的測量。第一步：脈沖的傳送產生一種簡單的超聲波

第二步：根據公式改變回波放大器的獲得量直到回撥被檢測到。第三步：檢測兩種回波的振幅與過零時間。

計算時間值 存儲結果

開外部中斷0

中原工學院畢業設計（論文）譯文

第四步：設置回波放大器的所得規格輸出，假定是3v。通過脈沖的周期設置下一個脈沖。根據第二部的數據設定時間窗。

第五步：發射兩竄脈沖產生干擾波。測量過零時間與回波振幅。如果逆向發生在回波中，決定要不通過在低氣壓插入振幅。

第六步：通過公式計算距離y。

中原工學院畢業設計（論文）譯文

4、超聲波測距系統的軟件設計

軟件分為倆部分，主程序和中斷服務程序。主程序完成初始化工作、各路超聲波發射和接收順序的控制。定時中斷服務子程序完成三方向超聲波的輪流發射，外部中斷服務子程序主要完成時間值的讀取、距離計算、結果的輸出等工作。

中原工學院畢業設計（論文）譯文

5、結論

對所要求測量范圍30cm-200cm內的平面物體做了多次測量發現，其最大誤差為1.5cm，且重復性好。可見基于單片機設計的超聲波測距系統具有硬件結構簡單、工作可靠、測量誤差小等特點。因此，它不僅可用于移動機器人，還可以用在其他檢測系統中。

思考：至于為什么不用接收管做放大電路，因為放大倍數搞不好，集成放大電路，還帶自動電平增益控制，放大倍數為76db，中心頻率是38k到40k，剛好是超聲波傳感器的諧振頻率。

中原工學院畢業設計（論文）譯文

參考文獻

1.Fox，J.D.，Khuri-Yakub，B.T.and Kino，G.S.，“High Frequency Acoustic Wave Measurement in Air”，in Proceedings of IEEE 1983 Ultrasonic Symposium，October 31-2 November，1983，Atlanta，GA，pp.581-4.2.Martin Abreu，J.M.，Ceres,R.And Freire,T.,“Ultrasonic Ranging: Envelope Analysis Gives Improved Accuracy”,Sensor Review, Vol.12 No.1,1992,pp.17-21.3.Parrilla， M., Anaya,J.J and Fritsch C.,‖Digital Signal Processing Techniques for High Accuracy Ultrasonic Range Measurement:,IEEE Transactions: Instrumentation and Measurement.Vol.40 No.4, August 1991,pp.750-63.4.Canali, C., Cicco, G.D., Mortem, B., Prudenziati, M., and Taron, A., ―A Temperature Compensated Ultrasonic Sensor Operating in Air for Distance and Proxinmity Measurement‖, IEEE Trasaction on Industry Electronics, Vol, IE-29 No.4,1982, pp.336-41.5.Martin, J.M., Ceres, R., Calderon, L and Freire, T., ‖Ultrasonic Ranging Gets Themal Correction‖, Sensor Review, Vol, 9 No.3, 1989,pp.153-5.中原工學院畢業設計（論文）譯文

Ultrasonic ranging system design Publication title: Sensor Review.Bradford:1993.Vol.13 ABSTRACT: Ultrasonic ranging technology has wide using worth in many field, such as the industrial locale, vehicle navigation and sonar engineering.Now it has been used in level measurement, self-guided autonomous vehicles, fieldwork robots automotive navigation, air and underwater target detection, identification ,location and so on.So there is an important practicing meaning to learn the ranging theory and ways deeply.To improve the precision of the ultrasonic ranging system in hand, satisfy the request of the engineering personal for the precision,the bound and the usage, a portable ultrasonic ranging system based on the single chip processor was developed.Keywords: Ultrasound r, Ranging System, Single Chip Processor

1.Introductive With the development of science and technology, the improvement of people’s standard of living, speeding up the development and construction of the city.Urban drainage system have greatly developed their situation is constantly improving.However, due to historical reasons many unpredictable factors in the synthesis of her time, the city drainage system.In particular drainage system often lags behind urban construction.Therefore, there are often good building excavation has been building facilities to upgrade the drainage system phenomenon.It brought to the city sewage, and it is clear to the city sewage and drainage culvert in the sewage treatment system.Confort is very important to people’s lives.Mobile robots designed to clear the drainage culvert and the automatic control system Free sewage culvert clear guarantee robot, the robot is designed to clear the culvert sewage to the core.Control System is the core component of the development of ultrasonic range finder.Therefore, it is very important to design a good ultrasonic range finder.1.1 subject background

With the development of economy and car scientific and technological progress, highway traffic presents driving fast pace, traffic dense is changed and the driver not professional trend.At the same time, along with the rapid development of auto industry, automobile yield and quantities are increased dramatically.But road development，中原工學院畢業設計（論文）譯文

transportation management is relatively backward, leading to a large number of traffic accidents in some cities, especially prominent.Intelligent transportation system in the world, ITS transportation science and technology of advanced technology, ITS exerting existing infrastructure of potential, enhance the transport efficiency, safeguard traffic safety and ease traffic wager plug, improving urban environment aspects of outstanding performance, has received the governments of widespread concern.The Chinese government is also highly intelligent transportation system of the development and popularization applications.The automotive anti-collision system as ITS development of a base, ITS success to the whole system has a very significant role.Traditionally, auto safety said can be divided into two main research direction: first,it is active safety technology, including the prevention of accidents, the way is now automotive safety research ultimate purpose;second, it is passive safety technique, namely the occupant protection after the accident.Now automotive safety field passive safety more research, mainly from the airbag, ABS(antilock brakes)and suspension from the aspects such as to ensure safety of personnel rides.From the economic and safety two ways, these passive safety measures is the accident of vehicle and personnel moments protection, with great limitations, thus vehicle active safety research is particularly important, leads to a of this study is based on single chip ultrasonic ranging system.This system is a kind of can advance to the driver issued audio-visual speech signal detection devices.It is installed in cars that can detect trying to approach the body of a car pedestrians and vehicles or around obstacles, Can send to the driver and crew imminent danger ahead of the signal, prompting a crash drivers take emergency measures to cope with special danger, avoid the loss.1.2 question design significance

Along with the development of modern society industrialization process, car this traffic tools are used for more and more people, but any problem has obvious that along with the increase in vehicles, traffic accident, which led to the frequent occurrence of casualties and property losses number astonishing.For highway traffic accident analysis showed that more than 80% of the accident due to the driver reaction inferior things, caused more than 65% of vehicle collision, the rest belongs to tracing cauda collided belongs to the side collision.Mercedes-benz Automobile Company for all kinds of traffic accident research shows that: if the driver can early 1S are aware

中原工學院畢業設計（論文）譯文

that a accident risk and take the appropriate corrective measures, the overwhelming majority of traffic accidents can be avoided.Therefore, vigorously research and development as the automotive anti-collision device etc active car auxiliary safe device, reduce the burden and misjudgments drivers to improve the traffic safety will play an important role.Obviously, this kind of product research and development has great realize meaning and broad application prospects.1.3 Ultrasonic ranging in automotive applications introduced

Ultrasonic back-draft rangefinder(known as electron optics)automotive anti-collision reversing device, can safe adjunct to sound or more intuitive digital form the dynamic display of around obstacles.Its earlier products is to use buzzer alarm, hum more anxious, and says vehicles from obstructions closer.Subsequent product can display the car from the body after the obstacles distance.Most of its products detection range in 0.4 ~ 1.5 m, some product can achieve 0.35 ~ 2.5 m, and have distance display, sound alarm, area-warning and azimuth instructions, some products also has the boot self-checking function.Still appeared on the market at present with voice alarm function of products.These products are the main problem is big, alarm measuring blind area lags behind, without considering the automobile braking inertial factors and make drivers brake lag, the anti-interference ability is not strong, misstatement or more.The automotive anti-collision radar is able to realize impact-proof alarm functions, basically have ultrasonic this intangible ruler, it recently obstacles distance measurement, and told to the owner.Actually ultrasonic range-finding principle simple: it emit ultrasonic echo, and receive reflected by microcontroller counter obtain both lag using formula S = t, Ct / 2 calculating distances, including S for cars and obstacles, C for the distance between the sound wave propagation in the medium speed.This paper introduces the ultrasonic ranging system only have 2 ultrasonic transducer(known as probe)respectively, decorate in cars left and right after after 2 position.Capable of detecting forward and reverse direction obstacle distance, the rearview mirror built-in display element display distance and direction, issued must be sound, plays the role of hints and alert.System USES a STC89C52 SCM two way ultrasonic signal cyclicly acquisition.Ultrasonic refers to the 20HHZ wave frequency is over.In order to use the ultrasonic detection means, must generate as ultrasonic wave and receiving damnation.Complete the functions of the device is called the

中原工學院畢業設計（論文）譯文

ultrasonic sensor, habit, ultrasonic transducer or ultrasonic probe.Ultrasonic sensors have both transmitters and receivers, but a ultrasonic sensors can also has the sending and receiving the sound waves of the dual role.Ultrasonic sensors is using the principle of piezoelectric effect and ultrasonic energy conversion, be in namely emit ultrasonic, energy conversion, launch ultrasonic, And in the stockades, received echo ultrasonic vibration into electrical signal.Ultrasonic ranging principle generally USES the time method for the crossing.First measured ultrasonic from the launch to meet obstacles returns experience of time, again multiply ultrasonic speed of get twice the distance between the sound source and obstacles.Measuring distance a variety of ways, short can use ruler, long-range laser displacement etc, are suitable for high accuracy of ultrasonic ranging in long distance measurement.Because of ultrasound in standard air of propagation speed 331.45 meters per second, by single-chip microcomputer is responsible for timing, SCM use 12.0 M crystals, so the system of measurement precision theory can achieve mm level.Because of ultrasonic directivity strong, energy consumption is slow, in a medium transmission distance, thus ultrasonic can be used for distance measurement.Using ultrasonic detection distance, the design is more convenient, computing procese also relatively simple, and the measurement precision can also meet the requirements.Ultrasonic generator can be divided into two kinds: one kind is to use electrical means producing ultrasonic, one kind is with mechanical approach to producing ultrasonic.This design belongs to nearly distance measurement, can use commonly used the piezoelectric ultrasonic transducer to achieve trigger unit.Using ultrasonic ranging work, can according to measuring launch reflection wave wave and the time interval between the measured distance, so as to achieve the effect.It mainly have three ranging methods:

(1)phase assay, phase assays high precision, but detection though limited range，(2)sound amplitude assay, acoustic amplitude assay vulnerable reflection wave influence;

(3)ferrying more time assay, crossing the time assay way of working is simple, intuitive, in hardware control and software design are very easy to implement.Its principle is: from the launch emit ultrasonic detection sensor, the gas medium spread to receive sensor of time, this time is crossing the more time.This design is the use of ultrasonic ranging the crossing the time assay.In the mobile vehicles of the application 15

中原工學院畢業設計（論文）譯文

of ultrasonic sensor is the use of ultrasound in air of directional spread and solid reflective characteristics(p-wave)and by receiving their launch ultrasonic reflecting signal, according to the ultrasonic issued and echo receiving the Windows and propagation speed, calculate transmission distance, thus obtains the obstacles to vehicle distance.中原工學院畢業設計（論文）譯文

2.A principle of ultrasonic distance measurement

2.1 the principle of piezoelectric ultrasonic generator

Piezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work.Ultrasonic generator, the internal structure as shown, it has two piezoelectric chip and a resonance plate.When it’s two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibration resonance, ultrasound is generated.Conversely, if the two are not inter-electrode voltage, when the board received ultrasonic resonance, it will be for vibration suppression, then it becomes the ultrasonic receiver.The traditional way to determine the moment of the echo’s arrival is based on thresholding the received signal with a fixed reference.The threshold is chosen well above the noise level, whereas the moment of arrival of an echo is defined as the first moment the echo signal surpasses that threshold.The intensity of an echo reflecting from an object strongly depends on the object’s nature, size and distance from the sensor.Further, the time interval from the echo’s starting point to the moment when it surpasses the threshold changes with the different intensities arriving exactly at the same tome will surpass the threshold at different moments.The stronger one will surpass the threshold earlier than the weaker, so it will be considered as belonging to a nearer object.2.2 The principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstracles on his way to return immediately, the ultrasonic reflected wave wave received by the reveiver immediately stop the clock.Ultrasonic in the air as the propagation velocity of 340m/s, according to the timer records the time t, we can calculate the distance between the launch distance barrier(s), that is:s=340t/2

中原工學院畢業設計（論文）譯文

3.Ultrasonic Ranging System for the Second Circuit Design

System is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 8751,economic-to –use, and the chip has 4K of ROM, to facilitate programming.Circuit schematic diagram shown in Figure 1.Figure 1 circuit principle diagram

中原工學院畢業設計（論文）譯文

3.1 40 kHz ultrasonic pulse generated with the launch

Ranging system using the ultrasonic sensor of piezoelectric sensors UCM40, its operating voltage of the pulse signal is 40kHz, which by the single-chip implementation of the following procedures to generate.Puzel:mov 14h,# 12h;ultrasonic firing continued 200ms here:cpl pl.0;output 40 kHz square wave

nop;

nop;nop;djnz 14h, here;ret Ranging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a 40kHz pulze output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms.Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.3.2 Reception and processing of ultrasonic

Used to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2.IC2 is locked loop with audio decoder chip LM567, internal voltage-controlled oscillator center frequency of f0=1/1.1R8C3, capacitor C4 determine their target bandwidth.R8-conditioning in the launch of the carrier frequency on the LM567 input signal is greater than 25Mv, the output from the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit port INT0 interrupt the highest priority, right or left location of the output circuit with output gete IC3A access INT1 port single-chip, while single-chip P1.3 and P1.4 received input IC3A, interrupted by the process to identify the source code is as follows: receivel:

push psw

push ace

中原工學院畢業設計（論文）譯文

cir ex1: related external interrupt 1

jnb p1.1, right;P1.1 pin to 0, ranging from right to interrupt service rountine circuit

jnb p1.2, left;P1.2 pin to 0, to the left ranging circuit

interrupt service routine return:SETB EX1;open external interrupt 1

pop

acc pop

psw reti right:…;right location entrance circuit interrupt service rountine

Ajmp Return left:…;left Ranging entrance circuit interrupt service rountine

Ajmp Return

3.3 The calculation of ultrasonic propagation time

When you start firing at the same time start the single-chip circuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time when you receive the ultrasonic reflected wave, the receiver circuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance.Some of its source is as follows: RECEIVE0: PUSH PSW PUSH ACC CLR EX0;related external interrupt 0 MOV R7, TH0;read the time value MOV R6, TL0 CLR C MOV A, R6 SUBB A,#0BBH;calculate the tome difference MOV 31H, A;storage results MOV A, R7 SUBB A,#3CH

中原工學院畢業設計（論文）譯文

MOV 30H,A SETB EX0;open external interrupt 0 POP ACC POP PAW RETI For a flat target, a distance measurement consists of two phases: a coarse measurement and, a fine measurement: Step 1: Transmission of one pulse train to produce a simple ultrasonic

Wave.Step 2: Changing the gain of both echo amplifiers according to equation，until the echo is detected.Step 3:detection of te amplitudes anf zero-crossing times of both echoes.Step 4:setting the gains of both echo amplifiers to normalize the output at, say 3 volts.Setting the period of the next pulses according to the: period of echoes.Setting the time window according to the data of step 2.Step 5:sending two pulse trains to produce an interfered wave.Testing the zero-crossing in the echo,detemine to otherwise calculate to by interpolation using the amplitudes near the trough.Derive t sub ml and t sub m2.Step6: Calculation of the distance y using equation.中原工學院畢業設計（論文）譯文

4.The ultrasonic ranging system software design

Software is divided into two parts, the main program and interrupt service routine.Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Tnterrupt service routines from time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to resd the value of completion time, distance calculation, the results of the output and so on.中原工學院畢業設計（論文）譯文

5.Conclusions

Required measuring range of 30cm~200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility.Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error.Therefore, it can be used not only for mobile robot can be used in other detection systems.Thoughts: As for why the receiver do not have the transistor amplifier circuit, because the magnification well, integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.中原工學院畢業設計（論文）譯文

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