1. 求 一篇 關於超聲波測距 的英文文獻及翻譯！
原文
Ultrasonic distance meter
Document Type and Number:United States Patent 5442592
Abstract:An ultrasonic distance meter cancels out the effects of temperature and humidity variations by including a measuring unit and a reference unit. In each of the units, a repetitive series of pulses is generated, each having a repetition rate directly related to the respective distance between an electroacoustic transmitter and an electroacoustic receiver. The pulse trains are provided to respective counters, and the ratio of the counter outputs is utilized to determine the distance being measured.
Publication Date:08/15/1995
Primary Examiner:Lobo, Ian J.
一、BACKGROUND OF THE INVENTION
This invention relates to apparatus for the measurement of distance and, more particularly, to such apparatus which transmits ultrasonic waves between two points.
Precision machine tools must be calibrated. In the past, this has been accomplished utilizing mechanical devices such as calipers, micrometers, and the like. However, the use of such devices does not readily lend itself to automation techniques. It is known that the distance between two points can be determined by measuring the propagation time of a wave travelling between those two points. One such type of wave is an ultrasonic, or acoustic, wave. When an ultrasonic wave travels between two points, the distance between the two points can be measured by multiplying the transit time of the wave by the wave velocity in the medium separating the two points. It is therefore an object of the present invention to provide apparatus utilizing ultrasonic waves to accurately measure the distance between two points.
When the medium between the two points whose spacing is being measured is air, the sound velocity is dependent upon the temperature and humidity of the air. It is therefore a further object of the,present invention to provide apparatus of the type described which is independent of temperature and humidity variations.
二、SUMMARY OF THE INVENTION
The foregoing and additional objects are attained in accordance with the principles of this invention by providing distance measuring apparatus which includes a reference unit and a measuring unit. The reference and measuring units are the same and each includes an electroacoustic transmitter and an electroacoustic receiver. The spacing between the transmitter and the receiver of the reference unit is a fixed reference distance, whereas the spacing between the transmitter and receiver of the measuring unit is the distance to be measured. In each of the units, the transmitter and receiver are coupled by a feedback loop which causes the transmitter to generate an acoustic pulse which is received by the receiver and converted into an electrical pulse which is then fed back to the transmitter, so that a repetitive series of pulses results. The repetition rate of the pulses is inversely related to the distance between the transmitter and the receiver. In each of the units, the pulses are provided to a counter. Since the reference distance is known, the ratio of the counter outputs is utilized to determine the desired distance to be measured. Since both counts are identically influenced by temperature and humidity variations, by taking the ratio of the counts, the resultant measurement becomes insensitive to such variations.
三、BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing will be more readily apparent upon reading the following description in conjunction with the drawing in which the single FIGURE schematically depicts apparatus constructed in accordance with the principles of this invention.
四、DETAILED DESCRIPTION
Referring now to the drawing, there is shown a measuring unit 10 and a reference unit 12, both coupled to a utilization means 14. The measuring unit 10 includes an electroacoustic transmitter 16 and an electroacoustic receiver 18. The transmitter 16 includes piezoelectric material 20 sandwiched between a pair of electrodes 22 and 24. Likewise, the receiver 18 includes piezoelectric material 26 sandwiched between a pair of electrodes 28 and 30. As is known, by applying an electric field across the electrodes 22 and 24, stress is inced in the piezoelectric material 20. If the field varies, such as by the application of an electrical pulse, an acoustic wave 32 is generated. As is further known, when an acoustic wave impinges upon the receiver 18, this inces stress in the piezoelectric material 26 which causes an electrical signal to be generated across the electrodes 28 and 30. Although piezoelectric transcers have been illustrated, other electroacoustic devices may be utilized, such as, for example, electrostatic, electret or electromagnetic types.
As shown, the electrodes 28 and 30 of the receiver 18 are coupled to the input of an amplifier 34, whose output is coupled to the input of a detector 36. The detector 36 is arranged to provide a signal to the pulse former 38 when the output from the amplifier 34 exceeds a predetermined level. The pulse former 38 then generates a trigger pulse which is provided to the pulse generator 40. In order to enhance the sensitivity of the system, the transcers 16 and 18 are resonantly excited. There is accordingly provided a continuous wave oscillator 42 which provides a continuous oscillating signal at a fixed frequency, preferably the resonant frequency of the transcers 16 and 18. This oscillating signal is provided to the molator 44. To effectively excite the transmitter 16, it is preferable to provide several cycles of the resonant frequency signal, rather than a single pulse or single cycle. Accordingly, the pulse generator 40 is arranged, in response to the application thereto of a trigger pulse, to provide a control pulse to the molator 44 having a time ration equal the time ration of a predetermined number of cycles of the oscillating signal from the oscillator 42. This control pulse causes the molator 44 to pass a "burst" of cycles to excite the transmitter 16.
When electric power is applied to the described circuitry, there is sufficient noise at the input to the amplifier 34 that its output triggers the pulse generator 40 to cause a burst of oscillating cycles to be provided across the electrodes 22 and 24 of the transmitter 16. The transmitter 16 accordingly generates an acoustic wave 32 which impinges upon the receiver 18. The receiver 18 then generates an electrical pulse which is applied to the input of the amplifier 34, which again causes triggering of the pulse generator 40. This cycle repeats itself so that a repetitive series of trigger pulses results at the output of the pulse former 38. This pulse train is applied to the counter 46, as well as to the pulse generator 40.
The transmitter 16 and the receiver 18 are spaced apart by the distance "D" which it is desired to measure. The propagation time "t" for an acoustic wave 32 travelling between the transmitter 16 and the receiver 18 is given by: t=D/V s
where V s is the velocity of sound in the air between the transmitter 16 and the receiver 18. The counter 46 measures the repetition rate of the trigger pulses, which is equal to 1/t. Therefore, the repetition rate is equal to V s /D. The velocity of sound in air is a function of the temperature and humidity of the air, as follows: ##EQU1## where T is the temperature, p is the partial pressure of the water vapor, H is the barometric pressure, Γ w and Γ a are the ratio of constant pressure specific heat to constant volume specific heat for water vapor and dry air, respectively. Thus, although the repetition rate of the trigger pulses is measured very accurately by the counter 46, the sound velocity is influenced by temperature and humidity so that the measured distance D cannot be determined accurately.
In accordance with the principles of this invention, a reference unit 12 is provided. The reference unit 12 is of the same construction as the measuring unit 10 and therefore includes an electroacoustic transmitter 50 which includes piezoelectric material 52 sandwiched between a pair of electrodes 54 and 56, and an electroacoustic receiver 58 which includes piezoelectric material 60 sandwiched between a pair of electrodes 62 and 64. Again, transcers other than the piezoelectric type can be utilized. The transmitter 50 and the receiver 58 are spaced apart a known and fixed reference distance "D R ". The electrodes 62 and 64 are coupled to the input of the amplifier 66, whose output is coupled to the input of the detector 68. The output of the detector 68 is coupled to the pulse former 70 which generates trigger pulses. The trigger pulses are applied to the pulse generator 72 which controls the molator 74 to pass bursts from the continuous wave oscillator 76 to the transmitter 50. The trigger pulses from the pulse former 70 are also applied to the counter 78.
Preferably, all of the transcers 16, 18, 50 and 58 have the same resonant frequency. Therefore, the oscillators 42 and 76 both operate at that frequency and the pulse generators 40 and 72 provide equal width output pulses.
In usage, the measuring unit 10 and the reference unit 12 are in close proximity so that the sound velocity in both of the units is the same. Although the repetition rates of the pulses in the measuring unit 10 and the reference unit 12 are each temperature and humidity dependent, it can be shown that the distance D to be measured is related to the reference distance D R as follows: i D=D R (1/t R )/(1/t) where t R is the propagation time over the distance D R in the reference unit 12. This relationship is independent of both temperature and humidity.
Thus, the outputs of the counters 46 and 78 are provided as inputs to the microprocessor 90 in the utilization means 14. The microprocessor 90 is appropriately programmed to provide an output which is proportional to the ratio of the outputs of the counters 46 and 78, which in turn are proportional to the repetition rates of the respective trigger pulse trains of the measuring unit 10 and the reference unit 12. As described, this ratio is independent of temperature and humidity and, since the reference distance D R is known, provides an accurate representation of the distance D. The utilization means 14 further includes a display 92 which is coupled to and controlled by the microprocessor 90 so that an operator can readily determine the distance D.
Experiments have shown that when the distance between the transmitting and receiving transcers is too small, reflections of the acoustic wave at the transcer surfaces has a not insignificant effect which degrades the measurement accuracy. Accordingly, it is preferred that each transcer pair be separated by at least a certain minimum distance, preferably about four inches.
Accordingly, there has been disclosed improved apparatus for the measurement of distance utilizing ultrasonic waves. While an illustrative embodiment of the present invention has been disclosed herein, it is understood that various modifications and adaptations to the disclosed embodiment will be apparent to those of ordinary skill in the art and it is intended that this invention be limited only by the scope of the appended claims.
譯文
超聲波測距儀
文件類型和數目：美國專利5442592
摘要：提出了一種超聲波測距儀來抵消的影響溫度和濕度的變化，包括測量單元和參考資料。在每一個單位，重復的一系列脈沖的產生，每有一個重復率，直接關繫到各自之間的距離，發射機和接收機。脈沖提供給各自的主機，和比例的反產出是利用確定的距離被衡量的。
出版日期： 1995年8月15日
主審查員：羅保.伊恩j.
一、背景發明
本發明涉及到儀器的測量距離，更特別是，這種儀器傳送超聲波兩點之間。
精密機床必須校準。在過去，這已經完成利用機械設備，如卡鉗，微米等。不過，使用這種裝置並不容易本身自動化技術。據了解，該兩點之間距離才能確定通過測量傳播時間的浪潮往返那些兩點。這樣一個類型的波是一種超聲波，或聲，海浪。當超聲波旅行兩點之間，距離兩個點之間可以衡量乘以過境的時間波由波速，在中期分開兩點。因此，這是一個對象本發明提供儀器利用超聲波准確測量兩點之間距離。
當中等兩個點之間的間距是被衡量的是空氣，聲速是取決於溫度和空氣相對濕度。因此，它是進一步對象的，現在的發明，提供儀器的類型所描述的是獨立於溫度和濕度的變化。
二、綜述發明
前述的和額外的對象是達到了根據這些原則的這項發明提供距離測量儀器，其中包括一個參考的單位和測量單位。參考和測量單位是相同的，每個包括一電發射機和接收機一電。間隔發射器和接收器的參考股是一個固定的參考距離，而間距之間的發射機和接收機的測量單位是距離來衡量。在每一個單位，發射機和接收機是再加上由一個反饋環路導致發射機產生的聲脈沖是由接收機和轉換成一個電脈沖這是然後反饋到發射機，使重復一系列脈沖的結果。重復率脈沖是成反比關系之間的距離發射器和接收器。在每一個單位，脈沖提供一個反。由於參考的距離是眾所周知，比例反產出是利用，以確定所期望的距離來衡量。由於這兩方面都是相同的影響，溫度和濕度的變化，採取的比例罪狀，由此產生的測量變得麻木等變化。
三、簡要說明圖紙
前述將更加明顯後，讀下列的說明，在與該繪圖並在其中單一數字schematically描繪儀器興建根據這些原則的這項發明。
四、詳細說明
談到現在的繪圖，有結果表明，測量單位和10個參考單位12個，均加上一個利用的手段14 。測量單位包括1 10電發射機16日和1電接收機18 。變送器16包括壓電材料20夾心階層之間的對電極的22日和24日。同樣，接收機18個，包括壓電材料26夾心階層之間的對電極的28日和30日。作為眾所周知，採用電場整個電極22日和24日，強調的是，誘導，在壓電材料20 。如果該欄位各有不同，如所申請的一個電脈沖，聲波是32所產生的。為進一步眾所周知，當聲波影響到接收器18 ，這誘導應力，在壓電材料26 ，導致一種電信號，以產生全國電極28日和30日。雖然壓電感測器已說明，其他電聲裝置，可利用，例如，靜電，駐極體或電磁類型。
如表所示，電極28日和30日的接收18歲以下的耦合的投入一34放大器，其輸出耦合輸入一個探測器36 。探測器36是安排提供一個信號，脈沖前38時，輸出放大器34已經超過預定的水平。脈沖前38 ，然後產生一個觸發脈沖，這是提供給脈沖發生器40 。在為了提高靈敏度，該系統，感測器16和18歲以下的共振興奮。有相應的提供了一個連續波振盪器42提供了一個連續振盪信號在一個固定的頻率，最好是共振頻率的感測器16和18 。這個振盪信號是提供給調制器44 。要有效地激發發射機16 ，可取的做法是提供幾個周期的共振頻率信號，而不是一個單脈沖或單周期。因此，脈沖發生器40是安排，在回應的應用存在的一個觸發脈沖，提供一個控制脈沖調制器44有一個時間的平等的時間，時間預定人數的周期振盪信號從振盪器42 。這個控制脈沖調制器的原因， 44個通過了「水管爆裂」的周期，以激發發射機16 。
當電力是適用於所描述的電路，有足夠的噪音在輸入到放大器34 ，其輸出觸發脈沖發生器40至造成了一片叫好聲，振盪周期，以提供整個電極22日和24日的發射器16 。變送器16因此產生聲波32條，其中影響到接收器18 。接收器18 ，然後產生一個電脈沖，這是適用於輸入放大器的34 ，這再次觸發原因的脈沖發生器40 。這個周期重演，使重復一系列的觸發脈沖結果的輸出脈沖前38 。這脈沖列車是應用到46個櫃位，以及向脈沖發生器40 。
變送器16日和接收18歲以下的間隔，除了由距離的「 D 」 ，它是理想的衡量。傳播時間的「 T 」為一聲波32往來變送器16日和接收18所給予的： = D的噸/視頻s
凡v s是聲速在空氣中之間的發射機16日和接收18 。櫃台46措施重復率觸發脈沖，這是平等的1 /湯匙因此，重復率是平等的一至中五的S /四該聲速空氣中是一個功能的溫度和濕度的空氣，內容如下： ＃ ＃ ＃ ＃ equ1其中T是溫度， P是局部的壓力，水汽， H是該氣壓， γ瓦特和γ一頃的比例不斷的壓力，具體的熱不斷貨量具體的熱水汽和乾燥的空氣，分別。因此，雖然重復率觸發脈沖測量非常准確地反46 ，聲速的影響，溫度和濕度，使測量的距離d無法確定準確。
根據這些原則的這項發明，參考單位提供的是12 。參考單位12是相同的建設為測量單位的10個，因此，包括一電發射機50個，其中包括壓電材料52夾心之間的一對電極的54和56 ，和一電接收機58 ，其中包括壓電材料60夾心階層之間的一對電極60,61,62和64 。再次，感測器以外的其他類型壓電可以利用。變送器50和接收五十八頃間隔，除了已知的和固定的參考距離「博士」 。電極60,61,62和64耦合到輸入的放大器66 ，其輸出是耦合的投入探測器68 。輸出探測器68是耦合的脈搏，前70產生觸發脈沖。觸發脈沖應用到脈沖發生器的72個控制調制器74通過掃射從連續波振盪器76至變送器50 。觸發脈沖從脈沖前70也適用於反78 。
最好是，所有的感測器16 ， 18 ， 50和58具有相同的共振頻率。因此，振盪器42和76都在運作，頻率和脈沖發電機40和第72條提供平等的輸出脈沖寬度。
在用法上，測量裝置10和參考資料股一十二頃在接近，使該聲速在這兩個單位是相同的。雖然留級率的脈沖在測量單位， 10和參考資料股十二頃每個溫度和濕度的依賴性，能證明的距離D來衡量。
其中T R是傳播時間超過距離博士在參考股12 。這種關系是獨立於雙方的溫度和濕度。
因此，產出的櫃台46和78所提供的投入微處理器的90個利用的手段14 。微處理器90是適當的程序提供了一個輸出是成正比的比例，產出的櫃台46和78 ，這反過來又是成正比的重復率分別觸發脈沖列車的測量單位， 10和參考資料股12 。作為描述，這個比例是獨立的溫度和濕度，由於參考的距離，博士，是眾所周知的，提供了一個准確的代表性距離四，利用手段， 14日還包括一個顯示92這是耦合和控制的微處理器，使90一個經營者可以隨時確定的距離四
實驗表明，當之間的距離發射和接收感測器是太小了，思考的聲波在感測器的表面有一個不小的作用，降低了測量精度。因此，最好是每換一雙分開，至少由某一個最小距離，最好是約四英寸。
因此，已披露的改善儀器的測量距離，利用超聲波。而一個說明性的體現，本發明已披露者外，據了解，各種修改和適應所披露的體現，將是顯而易見的那些普通的技巧與藝術，這是打算把這個發明只限於由范圍所附的索賠。
2. 聲波能否相互抵消 原理是什麼
不會抵消，波的傳播有獨立性原理。舉個形象的例子，你和你的老師同時說了一回句話，這時答你聽到的是兩個人的聲音，而不是什麼聲音也沒有聽到。這就說明聲波沒有抵消，仍然按其原有路徑傳播。如果抵消了你是聽不到聲音的
3. 2個相同的聲波相對可以抵銷，主動降噪的原理。 那2個光束相對，可以抵銷嗎
可以的，這是一個著名的干涉實驗，相位的疊加和歷史求和
偉大的樓主，如果我的回答對您有幫助，請務必點「採納"哦!謝謝合作！
4. 兩個聲波反向是不是可以抵消，那麼能量就憑空消失了嗎
兩個反相位的聲波是可以抵消一部分的，但是目前技術上不能完全抵消，會發生干涉。
抵消這個詞好像不太嚴謹，能量不會消失，抵消的是介質點的震動。
5. 聲波能否相互抵消 原理是什麼求答案
聲波有波峰和波谷，當一股聲波的波峰與另一聲波的波谷相疊加，而兩股聲波整幅相同，那麼疊加點就不產生震動，可以看做聲波抵消了
6. 雜訊抵消
原理上說，發出與馬路過來的雜訊強度一致，方向相反的聲波確實能起到降低室內雜訊的目的，這是基於聲強的方向性，也是主動降噪的一個方向。牆壁的隔聲還是比較強的，雜訊主要是從窗戶傳進來的。
7. 利用聲波的「疏部」「密部」在某些條件下會互相抵消的原理，開發出的反雜訊技術叫什麼
超聲波.
8. 兩個聲波反向是不是可以抵消，那麼能量就憑空消失了嗎 兩電磁波反向也可以抵消嗎那能量也憑空消失了
1.所有的波相遇都不會抵消，而是彼此相互穿過去，這個叫干涉。能量回決不會因此而消失的答。
2.在振動方向上如果兩列波的方向相反則會造成同一個質點振動抵消的情況，但這是在振動上的，能量由波所攜帶，不會因此消失。
9. 聲波在傳遞過程中，如果遇到相位相反的另一組聲波，就會相互抵消嗎
只能是某個位置相互抵消,而不是全空間抵消
畢竟傳遞過程中,振幅不斷減小
除非專聲源在同個屬地方,那麼因為在源頭就已經抵消了,所以也沒有聲場
聲源不同的兩個聲波,即便頻率一樣,在空間的聲強大小分布不可能完全同步,發生相位相反,只能是特定位置和角度
除非是恰巧都是同一個點的反射,恰巧反射處相位相反,恰巧反射後方向一致,才會在這個方向上全程抵消
如果方向不一致,實際抵消無從談起,如果方向相反,則相位恰好相反,是可以抵消
但是隨著位置的變化,兩個方向振幅大小隻有在相同振幅時候抵消,而之前之後是不能完全抵消的,總會存在差距
10. 關於利用反相聲波抵消聲音的試驗，請懂聲學的朋友幫忙看看。
左右聲道在發聲的時候反相並不代表著在空間中任意一個位置都是反相的。波在傳播版中是空間周權期性改變相位的。
想做到消聲，應該將你剛才編輯的和左聲道反相的聲音截出來作為一個單聲道的聲音，然後用兩個播放器同時播放這個單聲道的聲音和那個你處理後的聲音，你應該會發現左聲道幾乎無聲，而右聲道聲音很大。
不過這只是演示性質的實驗。實際上這個消聲原理並不是聲音的疊加，而是信號電流疊加消掉的。
FunctionStudio 你沒搞清楚我的實驗的意思吧。我實際上是在兩個不同的點：左喇叭和右喇叭分別產生相干削弱和相干加強。你仔細看看或許能明白，我實際上是在分析兩個位於同一位置的聲源的相干過程。這種情況下試問你到什麼地方去找你說的「有一些地方更強」？
利用音箱做演示的實驗我暫時只能想到這個了，歡迎大家繼續想新方法好了。