单片机超声波测距仪 外文翻译 外文文献 英文文献道
毕业设计论文 外文文献翻译 超声波测距 中英文对照
毕业设计论文外文文献翻译超声波测距中英文对照The Circuit Design of UltrasonicRanging System超声波测距系统的电路设计Ultrasonic Distance Meter超声波测距仪姓名:专业: 测控技术与仪器学号: 2007071071指导教师姓名,职称,:The Circuit Design of Ultrasonic Ranging SystemThis article described the three directions (before, left, right) ultrasonic ranging system is to understand the front of the robot, left and right environment to provide a movement away from the information. (Similar to GPS Positioning System)A principle of ultrasonic distance measurement1, the principle of piezoelectric ultrasonic generatorPiezoelectric ultrasonic generator is the use of piezoelectriccrystal resonators to work. Ultrasonic generator, the internal structure as shown in Figure 1, 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 vibrationresonance, ultrasound is generated. Conversely, if the two are notinter-electrode voltage, when the board received ultrasonic resonance,it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.2, the principle of ultrasonic distance measurementUltrasonic 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, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound 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 Ultrasonic Ranging System for the Second Circuit DesignSystem 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 2. Draw only the front range of the circuit wiring diagram, left and right in front of Ranging circuits and the same circuit, it is omitted.1,40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40, its operating voltage of the pulse signal is 40kHz, whichby the single-chip implementation of the following procedures to generate.puzel: mov 14h, # 12h; ultrasonic firing continued 200mshere: cpl p1.0; output 40kHz square wavenop;nop;nop;djnz 14h, here;retRanging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a40kHz pulse 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.2, reception and processing of ultrasonicUsed 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-controlledoscillator 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 outputfrom 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 output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3A access INT1 port single-chip, whilesingle-chip P1.3 and P1. 4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interruptpriority level for the first left right after. Part of the source codeis as follows:receive1: push pswpush accclr ex1; related external interrupt 1jnb p1.1, right; P1.1 pin to 0, ranging from right to interrupt service routine circuitjnb p1.2, left; P1.2 pin to 0, to the left ranging circuit interrupt service routinereturn: SETB EX1; open external interrupt 1pop accpop pswretiright: ...; right location entrance circuit interrupt serviceroutineAjmp Returnleft: ...; left Ranging entrance circuit interrupt service routineAjmp Return4, the calculation of ultrasonic propagation timeWhen you start firing at the same time start the single-chipcircuitry 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 receivercircuit 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 code is as follows:RECEIVE0: PUSH PSWPUSH ACCCLR EX0; related external interrupt 0MOV R7, TH0; read the time valueMOV R6, TL0?CLR CMOV A, R6SUBB A, # 0BBH; calculate the time differenceMOV 31H, A; storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0; open external interrupt 0POP ACCPOP PSWRETIFourth, the ultrasonic ranging system software designSoftware is divided into two parts, the main program and interrupt service routine, shown in Figure 3 (a) (b) (c) below. Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Interrupt service routines from time to time to complete three ofthe rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.V. CONCLUSIONSRequired 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 transistoramplifier circuit, because the magnification well, CX20106 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.超声波测距系统的电路设计本文所介绍的三方向(前、左、右)超声波测距系统，就是为机器人了解其前方、左侧和右侧的环境而提供一个运动距离信息。
超声波测距外文文献加中文翻译毕业设计
附录A 英文原文ULTASONIC RANGING IN AIRG. E. Rudashevski and A. A. GorbatovOne of the most important problems in instrumentation technology is the remote,contactless measurement of distances in the order of 0.2 to 10 m in air.Such a problem occurs,for instance,when measuring the relativethre edimensional position of separate machine members or structural units.Interesting possibilities for its solution are opened up by utilizing ultrasonic vibrations as an information carrier.The physical properties of air,in which the measurements are made,permit vibrations to be employed at frequencies up to 500 kHz for distances up to 0.5 m between a member and the transducer,or up to 60 kHz when ranging on obstacles located at distances up to 10 m.The problem of measuring distances in air is somewhat different from other problems in the a -pplication of ultrasound.Although the possibility of using acoustic ranging for this purpose has been known for a long time,and at first glance appears very simple,nevertheless at the present time there are only a small number of developments using this method that are suitable for practical purposes.The main difficulty here is in providing a reliable acoustic three-dimensional contact with the test object during severe changes in the air's characteristic.Practically all acoustic arrangements presently known for checking distances use a method of measuring the propagation time for certain information samples from the radiator to the reflecting member and back.The unmodulated acoustic(ultrasonic)vibrations radiated by a transducer are not in themselves a source of information.In order to transmit some informational communication that can then be selected at the receiving end after reflection from the test member,the radiated vibrations must be modulated.In this case the ultrasonic vibrations are the carrier of the information which lies in the modulation signal,i.e.,they are the means for establishing the spatial contact between the measuring instrument and the object being measured.This conclusion,however,does not mean that the analysis and selection of parameters for the carrier vibrations is of minor importance.On the contrary,the frequency of the carrier vibrations is linked in a very close manner with the coding method for the informational communication,with the passband of the receiving and radiating elements in the apparatus,with the spatial characteristics of the ultrasonic communication channel,and with the measuring accuracy.Let us dwell on the questions of general importance for ultrasonic ranging in air,namely:on the choice ofa carrier frequency and the amount of acoustic power received.An analysis shows that with conical directivity diagrams for the radiator and receiver,and assuming thatthe distance between radiator and receiver is substantially smaller than the distance to the obstacle,theamount of acoustic power arriving at the receiving area Pr for the case of reflection from an ideal planesurface located at right angles to the acoustic axis of the transducer comes towhere Prad is the amount of acoustic power radiated,B is the absorption coefficient for a plane wave inthe medium,L is the distance between the electroacoustic transducer and the test me -mber,d is the diameterof the radiator(receiver),assuming they are equal,and c~is the angle of the directivity diagram for theelectroacoustic transducer in the radiator.Both in Eq.(1)and below,the absorption coefficient is dependent on the amplitude and not on theintensity as in some works[1],and therefore we think it necessary to stress this difference.In the various problems of sound ranging on the test members of machines and structures,therelationship between the signal attenuations due to the absorption of a planewave and due to thegeometrical properties of the sound beam are,as a rule,quite different.It must be pointed out that the choiceof the geometrical parameters for the beam in specific practical cases is dictated by the shape of thereflecting surface and its spatial distortion relative to some average position.Let us consider in more detail the relationship betweenthe geometric and the power parameters ofacoustic beams for the most common cases of ranging on plane and cylindrical structural members.It is well known that the directional characteristic W of a circular piston vibrating in an infinite baffle is afunction of the ratio of the piston's diameter to the wavelength d/λ as found from the following expression:(2)where Jl is a Bessel function of the first order and α is the angle between a normal to the piston and aline projected from the center of the piston to the point of observation(radiation).From Eq.(2)it is readily found that a t w o-t o-o n e reduction in the sensitivity of a radiator with respectto sound pressure will occur at the angle（3）For angles α≤20.Eq.(3)can be simplified to（4） where c is the velocity of sound in the medimaa and f is the frequency of the radiated vibrations.It follows from Eq.(4)that when radiating into air where c=330 m/s e c,the necessary diameter of the radiator for a spedfied angle of the directivity diagram at the 0.5 level of pressure taken with respect to the fdc 76.05.0≈αaxis can befound to be（5）where disincm,f is in kHz,and α is in degrees of angle.Curves are shown in Fig.1 plotted from Eq.(5)for six angles of a radiator's directivity diagram.The directivity diagrm needed for a radiator is dictated by the maximum distance to be measured and bythe spatial disposition of the test member relative to the other structural members.In order to avoid theincidence of signals reflected from adjacent members onto the acoustic receiver,it is necessary to provide asmall angle of divergence for the sound beam and,as far as possible,a small-diameter radiator.These tworequirements are mutually inconsistent since for a given radiation frequency a reduction of the beam'sdivergence angle requires an increased radiator diameter.In fact,the diameter of the"sonicated"spot is controlled by two variables,namely:the diameter of theradiator and the divergence angle of the sound beam.In the general case the minimum diameter ofthe"sonicated"spot Dmin on a plane surface normally disposed to the radiator's axis is given by（6）where L is the least distance to the test surface. The specified value of Dmin corresponds to a radiator with a diameter（7）As seen from Eqs.(,6)and(7),the minimum diameter of the"sonieated"spot at the maximum requireddistancecannot be less than two radiator diameters.Naturally,with shorter distances to the obstacle the sizeof the"sonicated" surface is less.Let us consider the case of sound ranging on a cylindrically shaped object of radius R.The problem is to measure the distance from the electroacoustic transducer to the side surface of the cylinderwith its various possible displacements along the X and Y axes.The necessary angleαof the radiator'sdirectivity diagram is given in this case by the expression（8） whereα is the value of the angle for the directivity diagram,Ymax is the maximum displacement of the cylinder's center from the acoustic axis,and Lmin is the minimum distance from the center of theelectroacoustic transducer to the reflecting surface measured along the straight line connecting the center ofthe m e m b e r with the center of the transducer.It is clear that when measuring distance,the"running"time of the information signal is controlled by thefd α1400≈fcL d 5.1=fcLD 6min =min maxarcsinL R y +≥αlength of the path in a direction normal to the cylinder's surface,or in other words,the measure distance isalways the shortest one.This statement is correct for all cases of specular reflection of the vibrations from thetest surface.The simultaneous solution of Eqs.(2)and(8)when W=0.5 leads to the following expression:(9) In the particular case where the sound ranging takes place in air having c=330 m/sec,and on theasstunption that L min <<R,the necessary d i a m e t e r of a unidirectional piston radiator d can be found fromthe fomula (10) where d is in cm and f is in kHz. Curves are shown in Fig.2 for determining the necessary diameter of the radiator as a function of theratio of the cylinder's radius to the maximum displacement from the axis for four radiation frequencies.Alsoshown in this figure is the directivity diagram angle as a function of R and Y rnax for four ratios of m i n i m u mdistance to radius.The ultrasonic absorption in air is the second factor in determining the resolution of ultrasonic rangingdevices and their range of action.The results of physical investigations concerning the measurement ofultrasonic vibrations air are given in[1-3].Up until now there has been no unambiguous explanation of thediscrepancy between the theoretical and expe -rimental absorption results for ultrasonic vibrations inair.Thus,for frequencies in the order of 50 to 60 kHz at a temperature of+25oC and a relative humidity of37%the energy absorption coefficient for a plane wave is about 2.5dB/m while the theoretical value is 0.3 dB/m.The absorption coefficient B as a function of frequency for a temperature of+25o Cand a humidity of37%according to the data in[2]can be described by Table 1.The absorption coefficient depends on the relative humidity.Thus,for frequencies in the order of 10 to20kHz the highest value of the absorption coefficient occurs at 20%humidity[3],and at 40%humidity theabsorption is reduced by about two to one.For frequencies in the order of 60 kHz the maximum absorptionoccurs at 30.7o humidity,dropping when it is increased to 98% or lowered to 10%by a factor of approximatelyfour to one.The air temperature also has an appreciable effect on the ultrasonic absorption[1].When thetemperature of the medium is increased from+10 to+30,the absorption for frequencies between 30 and 50kHz increases by about three to one.Taking all the factors noted above into account we arrive at the following approximate values for theabsorption coefficient:at a frequency of 60 kHz /3min =0.15 m -1 and~max=0.5-1;at a frequency of 200 ()maxmin 76.0y L R d +=λmax25fy R d ≈kHz/~min=0.6 m -1 and B max =2 m -1.（11）The values for the minimum~min and rnaxil-num~max"transmittance"coefficients were obtained in thea bsence of aerosols and rain.Their difference is the result of the possible variations in temperature over therange from -3 0 to+50~and in relative hmnidity over the range from 10 to 98%.The overall value ofthe"transmittance"is obtained by multiplying the values of g and 0 for given values of L,f,and d.L I T E R A T U R E C I T E DMoscow(1957).Moscow(1960).附录B 中文翻译在空气中超声测距G. E. Rudashevski and A. A. Gorbatov在仪器技术中远程是最重要的一个问题。
超声波测距外文文献
International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009EFFECT OF VARIATION OF SEPARATION BETWEEN THE ULTRASONIC TRANSMITTER AND RECEIVER ON THE ACCURACY OF DISTANCE MEASUREMENTAjay Kumar Shrivastava1, Ashish Verma2 and S. P. Singh31Department of Computer Application, Krishna Institute of Engineering and Technology, Ghaziabad (U.P.), Indiaajay@2Department of Physics and Electronics, Dr H S Gour University, Sagar (M.P.), Indiavermaashish31@3Department of Electronics and Communication, Noida Institute of Engineering and Technology, Ghaziabad (U.P.), Indiasahdeopsingh@ABSTRACTAccuracy of distance measurement of an object from an observation point such as a stationary or moving vehicle, equipment or person is most important in large number of present day applications. Ultrasonic sensors are most commonly used due to its simplicity and low cost. The accuracy of the measured distance is dependent on the separation between the ultrasonic transmitter and receiver. This dependency has been studied and reported in this paper. The result shows that the accuracy of distance measured is dependent on the separation between the transmitter and the receiver.KEYWORDSAccuracy of distance measurement, Ultrasonic sensor, distance measurement, microcontroller, sewer pipeline inspection, sewer pipeline maintenance, robotics.1. INTRODUCTIONDistance measurement of an object in front or by the side of a moving or stationary entity is required in a large number of devices and gadgets. These devices may be small or large and also quite simple or complicated. Distance measurement systems for such applications are available. These use various kinds of sensors and systems. Low cost and accuracy as well as speed are important in most of the applications. Hence ultrasonic sensors are most commonly used. To maintain the accuracy of measured distance the separation between transmitter and receiver is very important. In this paper, we describe the results of a study on the variation of error of measurement of distance of an object by varying the separation between the transmitter and receiver of the ultrasonic sensors by using microcontroller P89C51RD2. Ultrasound sensors are very versatile in distance measurement. They are also providing the cheapest solutions. Ultrasound waves are suitable both for air and underwater use [1].19International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Ultrasonic sensors are also quite fast for most of the common applications. In simpler system a low cost version of 8- bit microcontroller can be used to implement the system to lower the cost. We are applying this system for sewer inspection system. Sewer blockages have become quite common. The blockages have become more frequent due to the dumping of polythene bags, hair and solid materials into the sewer system [2], [3]. There has been no work done in this direction. This is a new study which is useful to find out the optimal separation between ultrasonic transmitter and receiver to measure small distances.2. PRINCIPLEUltrasonic transducer uses the physical characteristics and various other effects of ultrasound of a specific frequency. It may transmit or receive the ultrasonic signal of a particular strength. These are available in piezoelectric or electromagnetic versions. The piezoelectric type is generally preferred due to its lower cost and simplicity to use [5]. The transmitter and receiver are available either as single unit or as separate units. The Ultrasonic wave propagation velocity in the air is approximately 340 m/s, the same as sonic velocity. To be precise, the ultrasound velocity is governed by the medium, and the velocity in the air is calculated using the formula given below (1). V= 340+0.6(t-15) m/s t:temperature, °C (1)In this study, we assumed the temperature to be 20°C, so the velocity of ultrasound in the air is 343 m/s. Because the travel distance is very short, the travel time is little affected by temperature. It takes approximately 29.15µsec for the ultrasound to propagate through 1cm, so it is possible to have 1cm resolution in the system [6].3. EXPERIMENTAL SETUPThe system consists of a transmitter and a receiver module controlled by a microcontroller P89C51RD2. We have used a microcontroller development kit for testing of the system. We are using 40Khz ultrasound sensors for our experiments. The Simplified block diagram of the system is shown in Fig.1. In Fig. 1, the interrupt1 signal initiates the system. When the interrupt1 signal is generated, MCU starts the timer1 to measure time and simultaneously generates the controlled 40Khz pulses having a train of specific number of pulses. These pulses are applied to the amplifier circuit and after amplification the ultrasound transmitter transmits the pulse train in the direction of the object. These ultrasonic pulses are reflected from the object and travels back in different directions. These reflected waves arrive at receiver. After amplification and processing it generates signal interrupt. This is applied as interrupt2 to the MCU. Interrupt2 stops the timer1, and MCU calculates the time elapsed between the generation of the wave and reception of the wave. This time is proportional to the distance travelled by the waves. Using the formula, MCU calculates the distance of the obstacle and display it or transfer it to the part of the total system where it is used for further control. Using this elapsed time, we calculate the distance of the object from the ultrasonic sensors.20International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009INT1 MCU Ultrasound Transmitter CircuitTINT2 Receiver Amplifier Display RFig 1: Block Diagram of the System4. EXPERIMENTAL RESULTSThe waveforms of the transmitted and received waveforms of the ultrasonic signal is stored in Digital Storage Oscilloscope. We have taken the readings for various separation between tranmitter and reciever. We have measured the distance in the interval of 5cm. For every measured distance three reading have been taken. The table shows the average of the three readings. The maesured distance is calculated on the basis of travelled time. The formula to calculate the distance is given below: Dist. (cm) = (Travelled Time*10-6 * 34300) / 2 (2)The ultrasonic waves travelled from the transmitter to the object and from the object back to the receiver hence the whole distance is divided by two. Values of %Error have also been calculated and shown. The error result shows that there is some error in recording the start and finish times in the system. When the distance increases the error is distributed in a larger distance and hence the %error decreases. We have taken the measurements for various separations of transmitter and receiver renging from 2cm to 15cm. The Table 1 shows the results when separation between tranmitter and reciever is 2cm. Table 1: Experimental Results (For 2cm Separation between Transmitter and Reciever) S.No . 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 400 690 1050 1250 1650 1930 2180 2400 2700 3000 Measured Distance (cm) 6.86 11.83 18.01 21.44 28.30 33.10 37.39 41.16 46.31 51.45 % Error 37.20 18.34 20.05 7.19 13.19 10.33 6.82 2.90 2.90 2.90The result shows that the acuracy of measured distance is increses for longer distances. The %error becomes constant for measured distances above 40cm. The highest %error is occured in small distance of 5cm. It is also shown by Fig.2.21International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Fig. 2: Graph of Actual Distance versus Measured Distance for 2cm Separation between Transmitter and Reciever. The Table 2 shows the result when separation between transmitter a reciever is 5cm. Table 2: Experimental Results for 5cm Separation between Transmitter and reciever) S.No. 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 410 700 1000 1300 1600 1870 2220 2500 2780 3120 Measured Distance (cm) 7.03 12.01 17.15 22.30 27.44 32.07 38.07 42.88 47.68 53.51 % Error 40.63 20.05 14.33 11.48 9.76 6.90 8.78 7.19 5.95 7.02The resluts shows that the accuracy is incresed in camparison to the previous results. This is also shown by the Fig. 3.Fig. 3: Graph of Actual Distance versus Measured Distance when Separation between Transmitter and Reciever is 5 cm.22International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009The Table 3 shows the results when separation between transmitter and reciever is 10 cm. These results indicates that when we increase the separation between transmitter and receiver the %error increses for small measured distances. Table 3: Experimental Results for Separation of 10cm between Transmitter and reciever)S.No. 1 2 3 4 5 6 7 8 9 10Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50Travelled Time (µSec) 620 750 1010 1310 1600 1870 2200 2400 2680 3000Measured Distance (cm) 10.63 12.86 17.32 22.47 27.44 32.07 37.73 41.16 45.96 51.45% Error 112.66 28.63 15.48 12.33 9.76 6.90 7.80 2.90 2.14 2.90Again the accuracy increases with the distance but the small distances are not so accurate. The error is high for small distances. It is also shown by the Fig. 4.Fig. 4: Graph of Actual Distance versus Measured Distance when Separation between Transmitter and Reciever is 10 cm. The Table 4 is showing the result of measured distance when 15cm separation between transmitter and reciever. These results shows that when we increase the separation between transmitter and receiver the %error increses. This increase is very high in small measured distances like 5cm in our experiment. The lowest %error observed for the measured distance of 45cm and again it is increasing for the measured distance of 50cm. The results shows that we have to stop the increament of seaparation between transmitter and receiver in our experiment.23International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Table 4: Experimental Results for 15cm Separation between Transmitter and Reciever) S.No. 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 1300 930 1180 1350 1620 1900 2200 2420 2700 3200 Measured Distance (cm) 22.30 15.95 20.24 23.15 27.78 32.59 37.73 41.50 46.31 54.88 % Error 345.90 59.50 34.91 15.76 11.13 8.62 7.80 3.76 2.90 9.76Again the error for the small distance say 5cm is very high. It is also showing that the graph between actual distance versus measured distance is not a straight line. This graph is shown in Fig. 5.Fig. 5: Graph of Actual Distance versus Measured Distance for 15cm Separation between Transmitter and Reciever. The graph between the measured distance the actual distance indicates that the measured distance is proportional to the actual distance.5. ANALYSIS OF THE RESULTSThe experimental results shows that the distance measured for different separations between transmitter and receiver are accurate for long distances e.g. more than 20cm. For small actual distances say 5cm, the small transmitter and receiver distances are better in comparison to the long distances between transmitter and receiver. If we place the transmitter and receiver at 15cm separation than the small distance like 5cm are not going to be measured correctly. Result shows the error of 345%. Hence we have to place the transmitter and receiver at proper distance like 5-10cm. For long distances the distance between transmitter and receiver has very low impact on the accuracy. We have compared the all measured distances for different separations between transmitter and receiver and the results are shown in the Table 5.24International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Table 5: Comparison of Measured Distances for different Separations between Transmitter and Reciever Actual Dist. (cm) 5 10 15 20 25 30 35 40 45 50 Measured Distance (in cm) when Separation between Transmitter and Reciever is = 2cm 6.86 11.83 18.01 21.44 28.30 33.10 37.39 41.16 46.31 51.45 5cm 7.03 12.01 17.15 22.30 27.44 32.07 38.07 42.88 47.68 53.51 10cm 10.63 12.86 17.32 22.47 27.44 32.07 37.73 41.16 45.96 51.45 15cm 22.30 15.95 20.24 23.15 27.78 32.59 37.73 41.50 46.31 54.88S. No. 1 2 3 4 5 6 7 8 9 10As we can see in the table that small measured distance like 5cm is measured accurately when 2cm separation between transmitter and receiver. It has the lowest error. When we increase the distance to be measured, the accuracy of measured distance are high and it the highest for 10cm separation between transmitter and receiver. Hence for the range of 5cm to 50cm, as we taken in our experiments, the separation between transmitter and receiver are 2cm to 10cm. If we increase this than the error percentage also increases. The Fig.6 shows the graph between actual distance and the different measured distances for various separations between transmitter and receiver.Fig. 6: Graph for Comparison of Measured Distances for different Separations between Transmitter and Reciever This graph is also showing that the graph plotting of measured distance when separation between transmitter and receiver is 2cm, 5cm and 10cm is almost on the same points. The graph plotting when 15cm separation between transmitter and receiver, is not very encouraging for this range of 5cm to 50cm.25International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 20096. CONCLUSIONSWe have done the experiments on our ultrasonic measurement system for the various separations between transmitter and receiver and the result shows that the measured distance is satisfactory for our study. When the distance increases the error becomes constant and very less. A correction may be applied to calculate the correct distance. Interrupt1 initiates the system and interrupt2 stops the timer and on the basis of the travelled time distance calculated. In future, the whole system will be mounted on the one PCB. This study shows that for small distances the separation between transmitter and receiver should be 5cm to 10cm. Hence this study will help in fixing the separation between transmitter and receiver in the robotic vehicle for blockage detection so we are able to calculate the more accurate distance of the blockage in the sewage filled sewer lines. Hence we can prevent human labour to go in the sewage filled sewer lines to detect the blockage which are very dangerous to the human as they contain the poisonous gases.ACKNOWLEDGMENTThis work is supported by MP Council of Science and Technology (MPCST), Bhopal, Project Code No. R&D/PHYSICS.23/08-09-1.REFERENCES[1] J. David and N cheeke “Fundamentals of Ultrasonic Waves” CRC Press, Florida, USA, 2002, ISBN 0-8493-0130-0. [2] Singh SP, Verma Ashish, Shrivastava AK “Design and Development of Robotic Sewer Inspection Equipment Controlled by Embedded Systems” Proceedings of the First IEEE International Conference on Emerging Trends in Engineering and Technology, July 16-18, 2008, Nagpur, India pp. 1317-1320. [3] Shrivastava AK, Verma Ashish, Singh SP “Partial Automation of the Current Sewer Cleaning System”, Invertis Journal of Science and Technology, Vol.1, No.4, 2008, pp 261-265. [4] O. Duran, K.Althoefer, and L Seneviratene, “State of the Art in Sensor Technologies for Sewer Inspection”, IEEE Sensors Journal, April 2002, Vol. 2, N.2, pp 63. [5] Hongjiang He, Jianyi Liu, “The Design of Ultrasonic Distance Measurement System Based on S3C2410” Proceedings of the 2008 IEEE International Conference on Intelligent Computation Technology and Automation, 20-22 Oct, 2008, pp. 44-47. [6] Yongwon Jang, Seungchul Shin, Jeong Won Lee, and Seunghwan Kim, “A Preliminary Study for Portable Walking Distance Measurement System Using Ultrasoinc Sensors” Proceedings of the 29th Annual International Conference of the IEEE EMBS Cité Internationale Lyon, France, Aug 23-26, 2007, pp. 5290-5293.26International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009AuthorsAjay Kumar Shrivastava was born at Guna (M.P.), India on 7th August, 1977. He had done his graduation in Electronics from Dr. H.S.Gour University, Sagar (M.P.), India in 1998. After that he had completed his MCA from the same university in 2002. He has more than seven years of teaching experience. He had worked as Lecturer in Technocrats Institute of Technology, Bhopal (M.P.), India for three years. Presently he is working as Associate Professor in Krishna Institute of Engineering and Technology, Ghaziabad (U.P.), India from Aug. 2005. His research interests include Embedded Systems and Data Mining. Mr. Shrivastava is the life member of Computer Society of India (CSI). He is also life member of Association of Computer, Electronics and Electrical Engineers (ACEEE) and International Association of Computer Science and Information Technology (IACSIT) and International Association of Engineers (IAENG). He is also the member of Computer Science Teachers Association (CSTA). He is also reviewer of various ACEEE organized conferences. He has published a paper in National Journal and published/presented four papers in conferences.Dr. Ashish Verma was born on 23rd March 1963. He received the M.Sc. degree in Physics with specialization in Electronics and solidstate physics in1984 and Ph.D. degree in Physics in 1991 from Dr. Hari Singh Gour Central University, Sagar, (M.P.), India. He has having 24 years of teaching (UG/PG) and research experience and is currently working as a Senior Lecturer in the department of Physics and Electronics, Dr. Hari Singh Gour Central University, Sagar. He has guided about 150 students (UG/PG) for their projects in the field of Electronics and Physics. He guided 4 Ph.D. students (One as Co-Supervisor). Presently, he is guiding 8 Ph.D. students for their innovative research. He is supervising 3 Ph.D. students in Physics and Electronics of M.P. BHOJ (Open) University, Bhopal, (M.P.), India. He had published a book entitled “Microprocessor”, Vishwavidyalaya Prakashan, Sagar (M.P.), India and written two chapters in “Bhotiki”, Madhya Pradesh Hindi Granth Academy, Bhopal (M.P.), India. Dr. Verma published / presented about 50 research papers in the National /International Journals / Conferences of high repute. He is the Executive Council (Government Nominee) in Government Girls Autonomous College, Sagar, (M.P.). He had worked in various committees of the university. Prof. S.P.Singh was born at village Manirampur in Nalanda district, Bihar, India on 10th June 1939. He did his schooling and intermediate studies at Patna. He completed his B.Sc.(Engg.) degree in Electrical Engineering from National Institute of Technology, Jamshedpur, India in the year 1964. He did M.Tech. in Electrical Engineering (Electronic Devices and Circuits) from Indian Institute of Technology, Kanpur, India in 1975. He obtained his Ph.D. degree from Ranchi University, Ranchi, India in the year 1993. His topic was microprocessor based speed control of induction motors.27International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009He joined N.I.T., Jamshedpur, India as Lecturer in Electrical Engineering in 1964 continued there as lecturer, AP and Professor till 1999. He started teaching electronic subjects and shifted to electronics engineering. After retirement from NIT in 1999, he continued to work as professor in institutes around Delhi. Currently, he is working as professor in Electronics & Communication Engineering at Noida Institute of Engineering and Technology, Greater Noida, U.P., India. Prof. Singh was a member of IEEE from 1974 to 1991. At present Dr. Singh is a fellow of I.E.T.E., India.28。
超声波测距系统外文文献翻译
=======大学本科生毕业设计外文文献及中文翻译文献题目： ULTRASONIC RANGING SYSTEM 文献出处： United States Patent译文题目：超声波测距系统学生：指导教师：专业班级：自动化11-4学号： 110601140416电气信息工程学院2014年5月1日超声波测距系统摘要超声波测距系统，是指选择性地激励一个变压器，使之产生换能器驱动信号。
超声换能器发射的超声波脉冲用于响应驱动信号然后接收到一个在超声波信号发出之后的回波信号。
分路开关接在变压器的绕组上，当超声波信号的传输在允许的近距离范围内达到一个稳定的等级，分路开关选择性的闭合来阻止蜂鸣器报警。
第1章发明背景像在宝丽来相机中应用的可用范围测试系统，它们都是准确而且可靠的，但都不适用于近距离测距，举个例子，2到3英寸的距离内就不适用，所以他们在9英寸甚至更远的距离测距是可靠的。
它们可以应用在很多的应用程序中，但不适用于可移动机器人领域内。
机器人通常必须通过门口只有两三英寸的间隙，如果当可移动机器人被操作于避障模式下通过狭小空间，可能机器人的规避路径过于狭窄，此外,规避动作应该使偏指定的路径距离最小化。
近距离测距不用于超声波系统的一个原因是，近距离输出脉冲输出太长以至于它重叠在回波脉冲上，即使输出脉冲缩短,输出脉冲仍然重叠回波脉冲，因为声音紧跟着输出脉冲。
备中产生的回波信号脉冲的范围为100毫伏，但设置传感器响应所必需的电路回声脉冲是大约150伏到300伏之间。
因此即使是最小的声波也会盖过回声信号。
事实上,dual-diode钳位电路用于将150伏降低到二极管的击穿电压，即0.7伏特。
但是这700毫伏足以盖过100毫伏的回波信号。
目前系统需要50毫秒将300伏特的峰值发射电压降到0.7伏特，且额外需要500到600毫秒的时间将它稳定在1毫伏范围。
第2章发明总结本发明可以提供一种改进的超声波测距系统。
本发明也可以提供一个改进的多通道超声波测距系统。
毕业论文外文文献翻译Ultrasonic-ranging-system-design超声测距系统设计
毕业设计（论文）外文文献翻译文献、资料中文题目：超声测距系统设计文献、资料英文题目：Ultrasonic ranging system design 文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：班级：姓名：学号：指导教师：翻译日期： 2017.02.14Ultrasonic ranging system designPublication title: Sensor Review. Bradford: 1993.Vol.ABSTRACT: Ultrasonic ranging technology has wide using worth in many fields, 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 personnel for the ranging precision, the bound and the usage, a portable ultrasonic ranging system based on the single chip processor was developed.Keywords: Ultrasound, Ranging System, Single Chip Processor1. IntroductiveWith the development of science and techno logy, 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 construction 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. Comfort 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 robots, 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.2. A principle of ultrasonic distance measurementThe application of AT89C51:SCM is a major piece of computer components are integrated into the chip micro-computer. It is a multi-interface and counting on the micro-controller integration, and intelligence products are widely used in industrial automation. and MCS-51 microcontroller is a typical and representative.Microcontrollers are used in a multitude of commercial applications such as modems, motor-control systems, air conditioner control systems, automotive engine and among others. The high processing speed and enhanced peripheral set of these microcontrollers make them suitable for such high-speed event-based applications. However, these critical application domains also require that these microcontrollers are highly reliable. The high reliability and low market risks can be ensured by a robust testing process and a proper tools environment for the validation of these microcontrollers both at the component and at the system level. Intel Plaform Engineering department developed an object-oriented multi-threaded test environment for the validation of its AT89C51 automotive microcontrollers. The goals of this environment was not only to provide a robust testing environment for the AT89C51 automotive microcontrollers, but to develop an environment which can be easily extended and reused for the validation of several other future microcontrollers. The environment was developed in conjunction with Microsoft Foundation Classes(AT89C51).1.1 Features* Compatible with MCS-51 Products* 2Kbytes of Reprogrammable Flash MemoryEndurance: 1,000Write/Erase Cycles* 2.7V to 6V Operating Range* Fully Static operation: 0Hz to 24MHz* Two-level program memory lock* 128x8-bit internal RAM* 15programmable I/O lines* Two 16-bit timer/counters* Six interrupt sources*Programmable serial UART channel* Direct LED drive output* On-chip analog comparator* Low power idle and power down modes1.2 Description。
汽车电子超声测距系统中英文外文翻译
中英文对照资料外文翻译文献Ultrasonic ranging system designABSTRACT: Ultrasonic ranging technology has wide using worth in many fields, 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 personnel for the ranging precision, the bound and the usage, a portable ultrasonic ranging system based on the single chip processor was developed.Keywords: Ultrasound, Ranging System, Single Chip Processor1. IntroductiveWith 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 construction 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 buildingfacilities 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. Comfort 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 robots, 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.2. A principle of ultrasonic distance measurementThe application of AT89C51:SCM is a major piece of computer components are integrated into the chip micro-computer. It is a multi-interface and counting on the micro-controller integration, and intelligence products are widely used in industrial automation. and MCS-51 microcontroller is a typical and representative.Microcontrollers are used in a multitude of commercial applications such as modems, motor-control systems, air conditioner control systems, automotive engine and among others. The high processing speed and enhanced peripheral set of these microcontrollers make them suitable for such high-speed event-based applications. However, these critical application domains also require that these microcontrollers are highly reliable. The high reliability and low market risks can be ensured by a robust testing process and a proper tools environment for the validation of these microcontrollers both at the component and at the system level. Intel Plaform Engineering department developed an object-oriented multi-threaded test environment for the validation of its AT89C51 automotive microcontrollers. The goals of this environment was not only to provide a robust testing environment for the AT89C51 automotive microcontrollers, but to develop an environment which can be easily extended and reused for the validation of several other future microcontrollers. The environment was developed in conjunction with Microsoft Foundation Classes(AT89C51).1.1 Features* Compatible with MCS-51 Products* 2Kbytes of Reprogrammable Flash MemoryEndurance: 1,000Write/Erase Cycles* 2.7V to 6V Operating Range* Fully Static operation: 0Hz to 24MHz* Two-level program memory lock* 128x8-bit internal RAM* 15programmable I/O lines* Two 16-bit timer/counters* Six interrupt sources*Programmable serial UART channel* Direct LED drive output* On-chip analog comparator* Low power idle and power down modes1.2 DescriptionThe AT89C2051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 2Kbytes of flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51 instruction set and pinout. By combining a versatile 8-bit CPU with flash on a monolithic chip, the Atmel AT89C2051 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.The AT89C2051 provides the following standard features: 2Kbytes of flash,128bytes of RAM, 15 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, a precision analog comparator, on-chip oscillator and clock circuitry. In addition, the AT89C2051 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The idle mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The power down mode saves the RAM contents but freezer the oscillator disabling all other chip functions until the next hardware reset.1.3 Pin Configuration1.4 Pin DescriptionVCC Supply voltage.GND Ground.Prot 1Prot 1 is an 8-bit bidirectional I/O port. Port pins P1.2 to P1.7 provide internal pullups. P1.0 and P1.1 require external pullups. P1.0 and P1.1 also serve as the positive input (AIN0) and the negative input (AIN1), respectively, of the on-chip precision analog comparator. The port 1 output buffers can sink 20mA and can drive LED displays directly. When 1s are written to port 1 pins, they can be used as inputs. When pins P1.2 to P1.7 are used as input and are externally pulled low, they will source current (IIL) because of the internal pullups.Port 3Port 3 pins P3.0 to P3.5, P3.7 are seven bidirectional I/O pins with internal pullups. P3.6 is hard-wired as an input to the output of the on-chip comparator and is not accessible as a general purpose I/O pin. The port 3 output buffers can sink 20mA. When 1s are written to port 3 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, port 3 pins that are externally being pulled low will source current (IIL) because of the pullups.Port 3 also serves the functions of various special features of the AT89C2051 as listed below.1.5 Programming the FlashThe AT89C2051 is shipped with the 2 Kbytes of on-chip PEROM code memory array in the erased state (i.e., contents=FFH) and ready to be programmed. The code memory array is programmed one byte at a time. Once the array is programmed, to re-program any non-blank byte, the entire memory array needs to be erased electrically.Internal address counter: the AT89C2051 contains an internal PEROM address counter which is always reset to 000H on the rising edge of RST and is advanced applying a positive going pulse to pin XTAL1.Programming algorithm: to program the AT89C2051, the following sequence is recommended.1. power-up sequence:Apply power between VCC and GND pins Set RST and XTAL1 to GNDWith all other pins floating , wait for greater than 10 milliseconds2. Set pin RST to ‘H’ set pin P3.2 to ‘H’3. Apply the appropriate combination of ‘H’ or ‘L’ logic to pins P3.3, P3.4, P3.5,P3.7 to select one of the programming operations shown in the PEROM programming modes table.To program and Verify the Array:4. Apply data for code byte at location 000H to P1.0 to P1.7.5.Raise RST to 12V to enable programming.5. Pulse P3.2 once to program a byte in the PEROM array or the lock bits. The byte-write cycle is self-timed and typically takes 1.2ms.6. To verify the programmed data, lower RST from 12V to logic ‘H’ level and set pins P3.3 to P3.7 to the appropriate levels. Output data can be read at the port P1 pins.7. To program a byte at the next address location, pulse XTAL1 pin once to advance the internal address counter. Apply new data to the port P1 pins.8. Repeat steps 5 through 8, changing data and advancing the address counter for the entire 2 Kbytes array or until the end of the object file is reached.9. Power-off sequence: set XTAL1 to ‘L’ set RST to ‘L’Float all other I/O pins Turn VCC power off2.1 The principle of piezoelectric ultrasonic generatorPiezoelectric 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, it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.T he 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 wellabove 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 surpa sses the threshold changes with the intensity of the echo. As a consequence, a considerable error may occur even two echoes with different intensities arriving exactly at the same time 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 measurementUltrasonic 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, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound 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 / 23. Ultrasonic Ranging System for the Second Circuit DesignSystem 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 875, economic-to-use, and the chip has 4K of ROM, to facilitate programming.3.1 40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic 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 200msHere: cpl p1.0; output 40kHz square wavenop;nop;nop;djnz 14h, here;retRanging 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 pulse 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 ultrasonicUsed 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 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 output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate 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 of inquiry to deal with, interrupt priority level for the first left right after. Part of the source code is as follows:Receivel: push pswpush accclr ex1; related external interrupt 1jnb p1.1, right; P1.1 pin to 0, ranging from right to interrupt service routine circuitjnb p1.2, left; P1.2 pin to 0, to the left ranging circuit interrupt service routinereturn: SETB EX1; open external interrupt 1pop accpop pswretiright: …; right location entrance circuit interrupt service routineAjmp Returnleft: …; left ranging entrance circuit interrupt service routineAjmp Return3.3 The calculation of ultrasonic propagation timeWhen 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 output 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 code is as follows:RECEIVE0: PUSH PSWPUSH ACCCLR EX0; related external interrupt 0MOV R7, TH0; read the time valueMOV R6, TL0CLR CMOV A, R6SUBB A, #0BBH; calculate the time differenceMOV 31H, A; storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0; open external interrupt 0\POP ACCPOP PSWRETIFor 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 the amplitudes and 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 times and amplitudes of the echoes. If phase inversion occurs in the echo, determine to otherwise calculate to by interpolation using the amplitudes near the trough. Derive t sub m1 and t sub m2.Step 6: Calculation of the distance y using equation.4、The ultrasonic ranging system software designSoftware 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.Interrupt service routines from time to time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.5、ConclusionsRequired 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 system.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.6、Parking sensor6.1 Parking sensor introductionReversing radar, full name is "reversing the anti-collision radar, also known as" parking assist device, car parking or reversing the safety of assistive devices, ultrasonic sensors(commonly known as probes), controls and displays (or buzzer)and othercomponents. To inform the driver around the obstacle to the sound or a moreintuitive display to lift the driver parking, reversing and start the vehicle around tovisit the distress caused by, and to help the driver to remove the vision deadends and blurred vision defects and improve driving safety.6.2 Reversing radar detection principleReversing radar, according to high-speed flight of the bats in thenight, not collided with any obstacle principles of design anddevelopment. Probe mounted on the rear bumper, according to different price and brand, the probe only ranging from two, three, four, six, eight,respectively, pipe around. The probe radiation, 45-degree angle up and downabout the search target. The greatest advantage is to explore lower than the bumper of the driver from the rear window is difficult to see obstacles, and the police, suchas flower beds, children playing in the squatting on the car.Display parking sensor installed in the rear view mirror, it constantlyremind drivers to car distance behindthe object distance to the dangerous distance, the buzzer starts singing, allow the driver to stop. When the gear lever linked into reverse gear, reversing radar, auto-start the work, the working range of 0.3 to 2.0 meters, so stop when the driver was very practical. Reversing radar is equivalent to an ultrasound probe for ultrasonic probe can be divided into two categories: First, Electrical, ultrasonic, the second is to use mechanical means to produce ultrasound, in view of the more commonly used piezoelectric ultrasonic generator, it has two power chips and a soundingboard, plus apulse signal when the poles, its frequency equal to the intrinsic oscillation frequency of the piezoelectric pressure chip will be resonant and drivenby the vibration of the sounding board, the mechanical energy into electrical signal, which became the ultrasonic probe works. In order to better study Ultrasonic and use up, people have to design and manufacture of ultrasonic sound, the ultrasonic probe tobe used in the use of car parking sensor. With this principle in a non-contactdetection technology for distance measurement is simple, convenient and rapid, easyto do real-time control, distance accuracy of practical industrial requirements. Parking sensor for ranging send out ultrasonic signal at a givenmoment, and shot in the face of the measured object back to the signal wave, reversing radar receiver to use statistics in the ultrasonic signal from the transmitter to receive echo signals calculate the propagation velocity in the medium, which can calculate the distance of the probe and to detect objects.6.3 Reversing radar functionality and performanceParking sensor can be divided into the LCD distance display, audible alarm, and azimuth directions, voice prompts, automatic probe detection function is complete, reversing radar distance, audible alarm, position-indicating function. A good performance reversing radar, its main properties include: (1) sensitivity, whether the response fast enough when there is an obstacle. (2) the existence of blind spots. (3) detection distance range.6.4 Each part of the roleReversing radar has the following effects: (1) ultrasonic sensor: used tolaunch and receive ultrasonic signals, ultrasonic sensors canmeasure distance. (2) host: after the launch of the sine wave pulse to the ultrasonic sensors, and process the received signal, to calculate the distance value, the data and monitor communication. (3) display or abuzzer: the receivinghost from the data, and display the distance value and provide differentlevels according to the distance from the alarm sound.6.5 Cautions1, the installation height: general ground: car before the installation of 45 ~55: 50 ~ 65cmcar after installation. 2, regular cleaningof the probe to prevent the fill. 3, do not use the hardstuff the probe surface cover will produce false positives or ranging allowed toprobe surface coverage, such as mud. 4, winter to avoid freezing. 5, 6 / 8 probe reversing radar before and after the probe is not free to swap may cause the ChangMing false positive problem. 6, note that the probe mounting orientation, in accordance with UP installation upward. 7, the probe is not recommended to install sheetmetal, sheet metal vibration will cause the probe resonance, resulting in false positives.超声测距系统设计超声测距技术在工业现场、车辆导航、水声工程等领域具有广泛的应用价值，目前已应用于物位测量、机器人自动导航以及空气中与水下的目标探测、识别、定位等场合。
外文翻译正文
H8/300L超声波测距仪（原文出处：第1页-第15页）介绍该应用说明介绍了一种使用H8/38024 SLP MCU的测距仪。
由单片机产生40KHz 方波，通过超声波传感器发射出去。
反射的超声波被另外一个传感器接收。
有效距离为6cm到200cm。
1.理论1.1概况在这篇应用说明中，H8/38024F微处理器是作为目标设备被使用的。
由于简单的可移植性，超声波测距仪使用的软件为C语言。
超声波是频率高于可听音的一切高于20kHz的声波。
用于医疗诊断和影像的超声波，频率延长和超过了10兆赫兹，高的频率有短的波长，这使得超声波从物体反射回来更容易。
不幸的是，极高的频率难以产生和测量。
对超声波的检测与测量主要是通过压电式接收机进行的。
超音波普遍应用于防盗系统、运动探测器和车载测距仪。
其他应用包括医疗诊断(人体成像)，清洁(去除油脂和污垢)，流量计(利用多普勒效应)，非破坏性试验(检测材料缺陷)，焊接等各个方面。
1.2软件实施距离的计算要测量超声波传感器接收到回波的时间。
理想的被测对象应该有一个大的面积而且不吸收超声波。
在这个应用说明中使用了38024f的CPU电路板。
图1展示超声波测距仪的工作原理，tmofh (脚63 )是用来传送0.5ms的40kHz的超声波，irq0 ( pin72 ) 是用来探测反射波的。
发送超声波后，计时器C开始追踪Timer Counter C (TCC)的计数数目，以计算物体的距离。
图1.测距仪工作原理1.2.1 发射超声波定时器F是一个具有内置式输出比较功能16位计数器，它还可以用来作为两个独立的8位定时器FH和FL，这里，定时器F是作为两个独立的8位定时器使用。
计时器的FL被初始化为产生中断，而FH在比较匹配发生时触发了tmofh的输出电平。
表1 计时器F的时钟选择对于为定时器的FL，选定内部时钟ø/32。
输出比较寄存器FL装载数据初值为H’FF 。
因此,外部定时器每1.67msec 产生一个中断，计算如下：/2ø晶振频率=，计时器FL 内部时钟周期=322⨯晶振频率=64MHz 8304.9=153.6kHz 中断周期=256kHz6.1531⨯=1.67msec 每隔65msec 开始发射一次超声波，计时器FL 须中断近39次( 65msec / 1.67msec = 39 )，才开始传送。
高精度超声波测距系统英文原文
High-precision Ultrasonic Ranging SystemAbstractThe ultrasound is easy to transmit and has good reflection. Its speed is far less than the speed of flight. So this paper designs an ultrasonic ranging system based on STC89C52RC. This system can be effective in the range of about372 cm. After repeated test, the measurement error can be less than 1 cm. So this system can be applied to intelligent avoidanceand vehicle transportation and other systems.Key words: SCM; ultrasound; send; receive; ranging;temperature compensationI. INTRODUCTIONAt present, the main methods of ultrasonic ranging include pulse-echo method, phase modulation, frequency modulation and FFT-based approach. In these methods, the pulse-echo method has good adaptability; this method not only can be used for manual testing, but also combined with the automated systems. So it is most widely used at home and aboard.Nowadays, the theories of microwave and laser ranging have been applied to the ultrasonic ranging system. It can be a very good research. On the other hand, the filtering and analysis of the echo can also draw more and more attention of many experts and scholars. With the enhanced understanding of the ultrasonic theory, we know how to improve the precision and the anti-jamming capabilities will be the most the important performance indicators.In this paper, the pulse-echo theory is used to design the entire system. The following content is mainly divided into three parts. The first section describes the hardware architecture of the system. The second part describes the software processing of the system. The third section describes the techniques of data processing. Insuch a case, the reader can have a comprehensive understanding of the system.II.THE PRINCIPLE OF ULTRASONIC RANGING SYSTEM Considering the requirement of the actual project, we choose the ultrasound, the frequency of which is 40 kHz. Ultrasonic sensor is this kind device which can converse the sound and the electrical power, also known as ultrasonic transducer or ultrasonic probe. In certain frequency range, it can convert the electrical signal to the external ultrasonic signal or change the external ultrasonic signal to the electricalsignal. In this paper, we choose the T/R40-12 piezoelectric ultrasonic transducer. It works at the frequency of 40 kHz. Its external diameter is 12cm.Ultrasonic generator sends the ultrasonic signal at a certain time. After the ultrasonic signal reflected from the measured object, the ultrasonic receiver can receive the signal. As long as we record the time between the sending time and the receiving time, we can calculate the distance from the ultrasonic sender to the measured object. The formula for calculating the distance is:D = S/2 = V ×T /2 (1)D is the distance between the ranging device and the measured object. S is the distance which the ultrasound transports. V is the speed of the ultrasound. T is the time which the ultrasound transports. Because ultrasound is also a kind of sound wave, the speed can be affected by the temperature. So in this paper, it uses the method of temperature compensation to improve the accuracy of the system.III.HARDWARE OF THE SYSTEMThe system block diagram of ultrasonic ranging system is fig. 1. The hardware mainly includes the SCM system, the display circuit, the temperature compensation circuit and the circuit of sending and receiving ultrasound.Fig.1 The block diagram of this systemA.The circuit of sending ultrasoundThe schematic of sending ultrasound is the figure 2. The sending circuit mainly includes the inverter and the ultrasonic transducer. At first the port P1.0 of SCM is inverted, connected to one pole of the ultrasonic transducer, and then inverted again, connected to another pole of the ultrasonic transducer. By means of this push-pull method, we can improve the emission intensity of the ultrasound. Paralleling the inverter; we can increase the driving capability of outputting. The pull-up resistor R1 and R2 not only increases the driving capability of outputting the high level, but alsoincreases the damping effect of the ultrasonic transducer and shorten the time of its free oscillations.Fig.2 The circuit of sending ultrasoundB. The circuit of receiving ultrasoundThe schematic of receiving ultrasound is the fig. 3.ASIC CX20106 is used for detecting infrared.Considering the carrying frequency of CX20106 is 38kz which is very close to the frequency of the ultrasound, we design the receiving circuit by making use of CX20106.Fig.3 The circuit of receiving ultrasoundC. SCM system and the display circuitSCM STC89C52RC is the core of this ranging system, by using the 12MHz crystal oscillator to obtain a more stable clock frequency and reduce the errors. The port P1.0 of the SCM output the 40 KHz square wave that is required by the ultrasonic transducer. The external interrupt 0 is used to monitor the returning signal. The simple and practical four bit common anode LED is used for the display circuit. The segment code is driven by 74LS245, and the bit code is driven by the transistor 9012. It is shown in fig. 4.Fig.4 SCM system and the display circuitD. The circuit of temperature compensationIn the ultrasonic ranging system, a good many factors can affect the speed, such as the environmental interference, the frequency of the base pulse, etc. But the environmental temperature can be the main factor. According to the formula (2), we can see that the temperature varies from 0 ℃to 40℃, the speed of ultrasound varies from 331.4m/s to 354.85m/s. Take the room temperature 20 as the base, the speed is 343.32m/s and the rate of change is 6.83%. So the temperature factor can not be ignored. In the summer, the temperature is often more than 40 . So in the ultrasonic ranging system, it is necessary to have the temperature compensation in order to reduce the error. Nowadays most of the temperature monitoring system takes the method of temperature sensor. First of all, we convert the temperature signal to the electric signal, secondly amplify the electric signal, and thirdly convert the analog signal to the digital signal by the A/D converter. This kind of circuit is very complex and can be easily affected by the parameters of the components. For these reasons, this paper uses the temperature sensor DS18B20 and SCM to design this precisiontemperature measurement system. It can increase the accuracy of the measurement to some extent. The port DQ of the DS18B20 can directly be connected to the port P3.7 of the SCM. The circuit is shown in fig. 5.Fig.5 The circuit of temperature compensationDS18B20 is the latest digital temperature sensor from America. It is different from the traditional thermistor temperature sensors. We can directly read the measured temperature values. According to the actual requirements, we can realize the 9 or 10 bit A/D conversion through simple programming. As a result, DS18B20 can make the system has a simpler structure and higher reliability. After measuring temperature, we correct the speed of the ultrasound by the following formula: V (T) = (331.05+0.607T) (m/s) (2)In the above formula, T is the Celsius temperature of the environment ( ℃ ). IV. SYSTEM PROGRAMMINGThe programming of the ultrasonic ranging system mainly include the main program, sending subroutine, receiving subroutine, temperature compensation subroutine and display subroutine. On one hand, the assembly language is efficient and easy. On the other hand, the ranging program not only need complex calculation, but also requires a highly accurate result. So we choose assembly language to design this system.A.The main programThe main program firstly initialize the system environment, set the T0 timer for the 16-bit timer mode, Secondly set the general interrupt enable bit EA, then initialize the display port P0 and P2. After measuring the temperature value by making use of the DS18B20, the temperature compensation subroutine modifies the sound speed. At this time, it begins to call the sending subroutine. In order to avoid the direct transmission from the transmitter to the receiver, It need a delay of about 0.1ms (this is the reason for the minimum distance can be measured), then enable the external interrupt 0 to receive the return signal. As a result of using the 12MHz crystal oscillator, the timer increase one, the interval is 1us, when the main program detects that the flag is successful, it start to calculate the distance according to the timer T0, the result will be sent for LED display. Then just repeat this processing. The main program flow chart is shown in fig.6.Fig.6 The flow chart of the main programB. Sending subroutine and receiving subroutineThe sending subroutine is the role of sending about 2 ultrasonic pulses through port P1.0 (about 40kHz square wave), the pulse width is about 12us. At the same time, the timer T0 starts timing. This system makes use of the external interrupt 0 to detect the echo. Once received the echo (the pin INT0 appears a low level), it immediately access to the interrupt program, then stop the timer T0 and set the successful flag. If the echo has not been detected when the timer overflow, the timer T0 overflow interrupt will close the external interrupt 0. At the same time, it clears the successful flag. It means that this ranging processing is unsuccessful.C. Temperature compensation subroutine and display subroutineAccording to the real-time temperature detected, it calculates the speed of sound by substituting the formula (2). Display program shows the distance in the way of look-up table.V.DATA PROCESSINGNot only the processing that the circuit deal with the signal will produce a fixed delay t, but also the processing that SCM collect the signal will produce a fixed delay t. Both the above process certainly lead to some measurement errors, But this system modify the delay to reduce the ranging error. Suppose that S1 and S2 are two fixed distance. t1 and t2 are corresponding to the two fixed distance respectively(including the t factor). So S1 and S2 are actually corresponding to the time t1- t and t2- t. That is S1=0.5V(t1- t),S2=0.5V(t2- t),it can be calculated:After several measurements, we can calculate the system delay t. According to the formula (1), we can determine the distance measured. This processing can reduce the system error to some extent.VI. ACTUAL MEASUREMENT AND ANALYSISThe measurement data is shown in table 7.Table 7.The actual measurement data (unit: cm)The experimental data show that: the blind spot of the ultrasonic ranging system (the least distance that the ultrasonic sensors can detect) is 25cm. The largest distance is 372cm. While designing the program, to avoid the direct transmission of the ultrasound from the transmitter to the receiver, the program has a delay about 1.4ms, so the ultrasonic ranging system has a least ranging distance. Because the propagation of the ultrasound may cause a certain decay and the transmit power is limited, it is difficult to detect the long-rang echo. So there will be a largest measurable distance. On the other side, the temperature compensation can improve the accuracy of the measurement.VII. CONCLUSIONIn this paper, it makes use of the reflection characteristics of ultrasound. We design this kind of ranging system based on STC89C52RC. Its effective range is from 25cm to 372cm by means of non-contact measurement. Once the environment temperature changes, it improves the measurement accuracy of the system by temperature compensation circuit. After modifying the system delay, it can reduce the system latency measurement error and have a significantly improved accuracy. The results validate the rationality of the system including both the hardware and the software. This ranging system is reliable and stable. It is fully able to meet a number of high-precision occasions, such as level measurement, robot positioning, etc. ACKNOWLEDGMENTFirst of all, I thank the IEEE for providing this template, secondly I want to thank my instructor Mr. Guo, last but not least, We sincerely thank all colleagues who previously provided technical support.REFERENCES[1] WANG AI ZH. Design and reality of ultrasonic ranging system base on the microcontroller[J]. Journal of Xinzhou Teachers University, 2010,26(2): 44-46. [2] KANG Y P, LIU ZH Y, GUO X, et al. Design of high-precision ultrasonic wave ranging system[J]. Experimental Technology and Management, 2010, 27(3): 61-64. [3] WANG ZH J, SU X Y, HAN Y P. Ultrasonic distance measurement system with high precision based on AT89C51 microprocessor[J]. Sensor Technology & Applocation, 2010(1): 21-24.[4] HAN L R. A survey of methods for improving ultrasonic ranging precision[J]. Telecommunication Engineering, 2010, 50(9): 132-136.。
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单片机超声波测距仪外文翻译外文文献英文文献道外文原文原文出处:传感器文摘布拉福德:1993年第13页 Ultrasonic rangingsystem design Publication title: Sensor Review. Bradford: 1993. Vol. 13ABSTRACT:Ultrasonic ranging technology has wide using worth in many fields，such as theindustriallocale，vehicle navigation and sonar engineering(Now it has been used inlevelmeasurement，self-guided autonomous vehicles fieldwork robots automotivenavigation，air andunderwater target detection，identification， So location and soon( there is an important practicingmeaning to learn the ranging theory and ways deeply. To improve the precision of the ultrasonicranging system in hand，satisfy the request of the engineering personnel for the ranging precision，the bound and the usage，a portableultrasonic ranging system based on the single chip processorwas developed(Keywords:Ultrasound r，Ranging System，Single Chip Processor1.Introductive With thedevelopment of science and technology the improvement of peoples standard ofliving speeding up the development and construction of the city. urban drainage system havegreatly developed their situation is constantly improving. However due to historical reasonsmany unpredictable factors in the synthesis of her time the city drainage system. In particulardrainage system often lags behind urban construction. Therefore there are often good buildingexcavation has been building facilities to upgrade the drainage system phenomenon. It brought tothe city sewage and it is clear to the city sewage and drainage culvert in the sewage treatmentsystem. comfort is very important to peoples lives. Mobile robots designed to clear the drainageculvert and the automatic control system Free sewage culvert clear guarantee robot the robot isdesigned to clear the culvert sewage to the core. Control System is the core component of thedevelopment of ultrasonic range finder. Therefore it is very important to design a good ultrasonicrange finder.2. A principle of ultrasonic distance measurement2.1 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 resonanceplate. When its two plus pulse signal the frequency equal to the intrinsic piezoelectric oscillationfrequency chip the chip will happen piezoelectric resonance and promote the development ofplate vibration resonance ultrasound is generated. Conversely if the two are not inter-electrodevoltage when theboard received ultrasonic resonance it will be for vibration suppression ofpiezoelectric chip the mechanical energy is converted to electrical signals then it becomes theultrasonic receiver. The traditional way to determine the moment of the echos arrival is based on thresholdingthe received signal with a fixed reference. The threshold is chosen well above the noise levelwhereas the moment of arrival of an echo is defined as the first moment the echo signal surpassesthat threshold. The intensity of an echo reflecting from an object strongly depends on the objectsnature size and distance from the sensor. Further the time interval from the echos starting pointto the moment when it surpasses the threshold changes with the intensity of the echo. As aconsequence a considerable error may occur Even two echoes with different intensities arrivingexactly at the same time will surpass the threshold at different moments. The stronger one willsurpass the threshold earlier than the weaker so it will be considered as belonging to a nearerobject.2.2The principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound in the moment to launch thebeginning of time at the same time the spread of ultrasound in the air obstacles on his way toreturn immediately the ultrasonic reflected wave received by the receiverimmediately stop theclock. Ultrasound in the air as the propagation velocity of 340m / s according to the timer recordsthe time t we can calculate the distance between the launch distance barrier s that is: s 340t /23.Ultrasonic Ranging System for the Second Circuit Design Systemis characterized by single-chip microcomputer to control the use of ultrasonictransmitter and ultrasonic receiver since the launch from time to time single-chip selection of8751 economic-to-use and the chip has 4K of ROM to facilitate ogramming. Circuitschematic diagram shown in Figure 2. Figure 1 circuit principle prdiagram3.1 40 kHz ultrasonic pulse generated with the launch Ranging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40 itsoperating voltage of the pulse signal is 40kHz which by the single-chip implementation of thefollowing procedures to generate.puzel: mov 14h 12h ultrasonic firing continued 200mshere: cpl p1.0 output 40kHz square wave nop nop nop djnz 14h here ret Ranging in front of single-chip termination circuit P1.0 input port single chipimplementation of the above procedure the P1.0 port in a 40kHz pulse output signal afteramplification transistor T the drive to launch the first ultrasonic UCM40T issued 40kHzultrasonic pulse and the continued launch of 200ms. Ranging the right and the left side of thecircuit respectively then input port P1.1 and P1.2 the working principle and circuit in front ofthe same location.3.2 Reception and processing of ultrasonic Used to receive the first launch of the first pair UCM40R the ultrasonic pulse modulationsignal into an alternating voltage the op-amp amplificationIC1A and after polarization IC1B toIC2. IC2 is locked loop with audio decoder chip LM567 internal voltage-controlled oscillatorcenter frequency of f0 1/1.1R8C3 capacitor C4 determine their target bandwidth.R8-conditioning in the launch of the carrier frequency on theLM567 input signal is greater than25mV the output from the high jump 8 feet into a low-level as interrupt request signals to thesingle-chip processing. Ranging in front of single-chip termination circuit output port INT0 interrupt the highestpriority right or left location of the output circuit with output gate IC3A access INT1 portsingle-chip while single-chip P1.3 and P1. 4 received input IC3A interrupted by theprocess toidentify the source of inquiry to deal with interrupt priority level for the first left right after. Partof the source code is as follows:receive1: push psw push acc clr ex1 related external interrupt 1 jnb p1.1 right P1.1 pin to 0 ranging from right to interrupt service routinecircuit jnb p1.2 left P1.2 pin to 0 to the left ranging circuit interrupt serviceroutinereturn: SETB EX1 open external interrupt 1 pop acc pop psw retiright: ... right location entrance circuit interrupt service routine Ajmp Returnleft: ... left Ranging entrance circuit interrupt service routine Ajmp Return3.3 The calculation of ultrasonic propagation time When you start firing at the same time start thesingle-chip circuitry within the timer T0 theuse of timer counting function records the time and the launch of ultrasonic reflected wavereceived time. When you receive the ultrasonic reflected wave the receiver circuit outputs anegative jump in the end of INT0 or INT1 interrupt request generates a signal single-chipmicrocomputer in response to external interrupt request the implementation of the externalinterrupt service subroutine read the time differencecalculating the distance . Some of its sourcecode 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 time difference MOV 31H A storage results MOV A R7 SUBB A 3CH MOV 30H A SETB EX0 openexternal interrupt 0 POP ACC POP PSW 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 the amplitudes and 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 times and amplitudes of the echoes. If phase inversion occurs in the echo determine to otherwise calculate to by interpolation using the amplitudes near the trough. Derive t sub m1 and t sub m2 .Step 6: Calculation of the distance y using equation .4. The ultrasonic ranging system software design Software is divided into two parts the main program and interrupt service pletion of the work of the main program is initialized each sequence of ultrasonictransmitting and receiving control.Interrupt service routines from time to time to complete three of the rotation direction ofultrasonic launch the mainexternal interrupt service subroutine to read the value of completiontime distance calculation the results of the output and so on.5. Conclusions Required measuring range of 30cm 200cm objects inside the plane to do a number ofmeasurements found that the maximum error is 0.5cm and good reproducibility. Single-chipdesign can be seen on the ultrasonic ranging system has a hardware structure is simple reliablesmall features such as measurement error. Therefore it can be used not only for mobile robot canbe used in other detection systems. Thoughts: As for why the receiver do not have the transistor amplifier circuit because themagnification well integrated amplifier but also with automatic gain control level magnificationto 76dB the center frequency is 38k to 40k is exactly resonant ultrasonic sensors frequency REFERENCES1. Fox J.D. Khuri-Yakub B.T. and Kino G.S. quotHigh Frequency Acoustic Wave Measurementin Airquot in Proceedings of IEEE 1983 Ultrasonic Symposium October 31-2 November 1983Atlanta GA pp. 581-4.2. Martin Abreu J.M. Ceres R. and Freire T. quotUltrasonic Ranging: Envelope Analysis GivesImproved Accuracyquot Sensor Review Vol. 12 No. 1 1992 pp. 17-21.3. Parrilla M. Anaya J.J. and Fritsch C. quotDigital Signal Processing Techniques for HighAccuracy Ultrasonic Range Measurementsquot IEEE Transactions: Instrumentation andMeasurement Vol.40 No. 4 August 1991 pp. 759-63.4. Canali C. Cicco G.D. Mortem B. Prudenziati M. and Taron A. quotA TemperatureCompensated Ultrasonic Sensor Operating in Air for Distance and Proximity MeasurementquotIEEE Transaction on Industry Electronics Vol. IE-29 No. 4 1982 pp. 336-41.5.Martin J.M. Ceres R. Calderon L and Freire T. quotUltrasonic Ranging Gets ThermalCorrectionquot Sensor Review Vol. 9 No. 3 1989 pp. 153-5.外文译文超声波测距仪系统设计原文出处:传感器文摘布拉福德:1993年第13页摘要:超声测距技术在工业现场、车辆导航、水声工程等领域都具有广泛的应用价值，目前已应用于物位测量、机器人自动导航以及空气中与水下的目标探测、识别、定位等场合。