Pound oscillatory type stock plan principle and experimental research

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Stock of 　 of 1 foreword 　 measure, especially the makings of solid stock measure, as a result of the sex of special other people of the object that be measured, be like dust, adhere, harden wait for action, contact of dispute of first-rate measurement technique is measured. Compare the blame such as ultrasonic type and radar type to contact a method, although be not contacted with the stock that be measured directly, but need to be contacted with medium of stock upper part, medium of need stock upper part has pair of ultrasonic or microwave is transparent, measurement technique of complete blame contact is had complete not with the stock that be measured, include contact of medium of stock upper part, have more extensive adaptability and higher reliability. Current and only measurement technique of contact of two kinds of complete blame: Radiative type and say to weigh type. Because radiative type expects plan need high-energy γ ray to penetrate be measured container, its run medium safety to defend the problem such as the memory with radiative source restricted the application of this kind of means. Say heavy style expects measure an instrument to have to medium density depend on directly, need has foregone and stable medium density, this is measured in the liquid in perhaps be the requirement that satisfies easily, often satisfy very hard in the measurement of solid medium. Because need to measure the weight of integral container, requirement container has only finite a steel structure tie-in, this also limitted the installation condition of the instrument. Carry theoretical analysis and experimental research, the new-style material that developed a kind to undertake in order to pound metrical with oscillatory method plan. Regard a kind of new-style complete blame as contact stock measurement technique, do not use high-energy ray, without radiative pollution, do not depend on density of the medium that be measured, do not have a requirement to container structure, entire apparatus installs Yu Rong implement exterior, do not need to contact with below two kinds of medium on the interface that be measured, be a kind clean, convenient, cheap, applicable and extensive new-style makings metrical method. The 2 fundamental that measure a principle are to carry container external the energy wave with vibrator proper generation, after the course travels, carry the message of circumstance of the interface inside container, be received by sensor place, through analysing the feature of wave, get interfacial information. Energy wave can choose electromagnetic wave or mechanical wave. Electromagnetic wave has frequency only enough Gao Cai has enough energy penetrable container (especially metallic container) , the radiative material that has used at present namely plan medium γ but relatively high-frequency machinery wave penetrates ability is differred, if supersonic type expects plan must install at container interior, although call blame contact to measure, it is with the interface that be measured two medium are not contacted one kind medium only, instrument need blasts off in another kind of medium with receive ultrasonic, this asks this kind of medium has supersonic and transparent character. Perhaps this kind of means ought to call half contact to measure. To can undertake be been not completely osculatory metrical, the choice uses wave of low frequency machinery, can arise from the wall outside container with receive, not only easy generation, detect easily, and container and the medium that be measured is small to the attenuation of wave, when a large number of Cheng this are attached most importance to especially should. But wave of low frequency machinery is disturbed easily by noise, because wavelengh is longer, to measuring precision rise to also bring a lot of difficulty. These raise very tall requirement to signal processing. In the transmission process of wave of low frequency machinery, can regard container wall have quality of certain unit area, have isotropy cut stretch model amount, each to even laminose medium. Observe medium from the angle of total parameter, can regard many more infinite the quality of identical parameter -- bedspring -- damp 2 rank cascade structure of the system. Can be being regarded to sensor from vibrator is the intercept in growing chain indefinitely is finite 2 rank have damp system. Be measured to having inside container the container wall of medium, be opposite as a result of the medium that be measured the lateral pressure of container wall, make the equivalent quality of container wall increases. Be opposite as a result of the medium that be measured again the conduction of wave energy, the equivalent damp of container wall increases. However, lateral pressure cuts stretch model to measure an effect to the equivalent of container wall not big however. Such, in principle passes mode analysis, can find the correlativity between oscillatory mode and medium interface, achieve metrical goal thereby. But such measurement is to rely on specific container and the object of the specific medium that be measured, do not have economic value. Use activator and sensor matrix, the measurement that builds much input, much output system and corresponding system deliver a model, be based on the transmission of wave and quicken impedance model, through the measurement that blame mode changes and signal processing technique, be in need not below the circumstance of container and parameter of the stock that be measured, had stock measure. 3 systems are designed 3. 1 construction of system pounds oscillatory type to expect plan if the construction of system of test facilities pursues 3, 1. Experiment container is 1m of a diameter, it is high 1. Of 8m cylindrical 3 Mm is thick 45 ＃ armor plate coils make solder steel tub. Vibrator installation is outside container wall, in spot of 8 vibrator imitate was being used to measure in the experiment, be measured vessel is very old (span is very big, right now power of onefold vibrator drive cannot satisfy a requirement) the state when, from the top prolapse is arranged equably continuously, span is 20cm. Sensor is acceleration sensor, go up in the wall outside container through adsorption of permanent magnet base, altogether 4, support oneself likewise and prolapse is arranged equably continuously. Use this kind of many vibrator and sensor to distributing range way, each vibrator and sensor form structure of redundant much sensor, through confluence of much sensor information, not only expanded span, have the fault tolerance capacity on hardware more, raised systematic dependability. The interference rejection ability of the dependability of the precision that and redundant information also rose greatly measures, data and instrument. Vibrator is hanged receive the control bus line in the system to go up, to each vibrator allocation has its independent address number, suffer control of control bus line to have in same time and only a vibrator is chosen to connect. Aleatoric weaveform produces calorie of installation to be on another servo computer, through aether network and advocate accuse computer newsletter, receive advocate the undee data that dominates the computer to give out and control signal. After incentive weaveform produces calorie of generation via aleatoric weaveform, by power amplifier is magnified, by be chosen to connect vibrator changeover to be wall of container of mechanical wave drive currently. Mechanical wave carries the transmission of bucket wall, be received by sensor, changeover is telegraphic date, classics join ever since amplifier of 4 programmed control. The signal after enlarge is entered through keeping apart amplifier to keep apart evacuation advocate accuse the computer to undertake data is collected, signal of number of quantity melt into undertakes digital signal is handled. Servo computer not only the weaveform that controls aleatoric and undee generator to produce need, and still holding the position of an interpreter advocate the picks a gain with programmed control amplifier job that controls the instruction of the computer to controlling vibrator to control bus line. 3. Vibrator of 2 vibrator design is optional the structure of electromagnetism of an organic whole that open, basically comprise core, coil, permanent magnet, 4 parts comprise control circuit. Incentive muscularity is A of 50 G ／ about, in power amplifier the biggest incentive electric current is 10A (occupy sky comparing 1 ∶ 10) when, force of the biggest output is vibrator 500g. Effective transmission bands is in vibrator 200 ～ 16 000Hz. Control circuit answers the address signal that dominates bus line, coding. This vibrator is chosen when be identical of signal of bus line address and encode of this vibrator address, the line that makes the coil of vibrator and bus line medium puts through, enter pick an on call state. When line by power amplifier drive when, the permanent magnet of vibrator gets power below the action of coil magnetic field, bring to bear on this one incentive force the container wall of as close together as its felt, on container wall drive gives mechanical and oscillatory wave. 3. 3 oscillatory sensor choose to be the circumstance that gets used to different container, will measure the vibration of bucket wall with acceleration sensor. Acceleration sensor has wider transmission bands. Adoption sensor 3db even bandwidth is 0 ～ 10 000Hz, sensitivity is 100mV ／ G. To go to the lavatory with coupling of steeliness container wall, made appropriative magnet base. Carry snail column and sensor firm link, pass magnetic force and container wall adsorption. Perpendicular come off force is 5kg, contented acceleration sensor installs a condition. 3. Generator of 4 aleatoric weaveform measures the processing of signal to go to the lavatory to make, undee to drive spectrum and duration are having special demand. To produce this kind of complex transient state sheet second pulse, advocate after accusing the computer to get signal weaveform through numeric computation, convey undee data to servo computer through the network, store in the cache that produces card in aleatoric weaveform. Be in advocate after accusing the computer to issue actuating signal, weaveform happening gets stuck to lead parameter in order to dictate middle finger decides sampling to undertake to data D ／ A alternates, output the incentive signal of expectation. What the author uses is Sai200 aleatoric weaveform produces card, memory deepness is 32kbye, rate of the biggest sampling is 20MHz, voltage of weaveform of the biggest output is ± 5V. Achieve the power amplifier of 400 W through power of made 10ms peak value, drive vibrator to produce incentive vibration. 3. 4 distance accuse amplifier of programmed control of 4 5 segregation the key that amplifier is this device. As a result of every time drive is short pulse, duration is short, and the relative strength that each drive answers also is important parameter. So, the signal that cannot use method of automatic gain control to get used to different measurement asks to what amplifier gain differs. The author used the method of gain of computer programmed control to solve this problem. Additional, in the spot be linked together with container wall cheek by jowl as a result of acceleration sensor, each sensor be apart is very far, carry sensor in all the crust of the ground, container wall, many sensor surrounded very large area close electric loop, this can draw very big annular interference electric current in spot environment, and cannot undertake overcoming with the method such as screen. This causes intense interference to faint oscillatory signal, to follow-up signal processing brings a lot of difficulty. Author design made amplifier of gain of programmed control of low noise of 4 segregation broadband, undertake the programmed control of independent insulation ground, enlarge to 4 signal, graph 3, 2 be among them all the way amplifier. The signal after 4 insulation ground magnifies is kept apart through keeping apart amplifier, after becoming in all signal, output enters the data of A ／ D of the computer to collect card to make modulus shift. The keeps apart the computer with isolator of switch smooth Ou number in circuit controls signal, the control word that regards D ／ as A general computer with DAC0832 changes the imitate voltage that is gain control. With broadband of programmed control low noise compositive amplifier AD603 is made give priority to amplifier, switch capacitance type ISO124 of integrated circuit of 1 segregation enlarge regards 1 ∶ as segregation amplifier. The gain control limits of amplifier is 0 ～ 80db, linear and adjustable, bandwidth is 10Hz ～ 5MHz, the segregation between the passageway is spent be more than - 80db, the letter a confusion of voices that gained satisfaction in the experiment is compared. 3. 6 software structure is on hardware structure, test facilities cent is principal and subordinate two computers unit, this is the working structure that dismantles in group control circumstance for analogue instrument. From control the computer in the spot, cost ability of low, operation loses, basically be the control that makes hardware equipment, wait like vibrator, amplifier. Advocate control the computer an area has only, the processing of responsible signal works, operation capability is strong. Such, on software, the system also is divided for many processes, so that distributing,move on many processor. Integral structure sees a picture 3, 3. Advocate accuse computer use to have 4 processes all right, among them signal collects process and central control process to pass WM - COPYDATA message has communication. The center that the process such as other signal processing weaves through the data engine interface of Matlab and VC controls process communication. Pass word of Sockets dowel joint, advocate accuse the computer and from accuse the computer to have news report, control respectively move at from two processes that control the computer to go up. When measuring, advocate the gain of the address number that controls a process to connect associate to accuse the bus line of the computer to control module to adjust vibrator above all and programmed control amplifier, activation next signal collects module, enter collect preparative condition. Then, actuating signal produces module, generation theory is incentive and undee, convey weaveform to produce card to control module to produce drive from the weaveform that controls the computer again. After drive is given out, signal collects module to get signal, the end awaits condition, give the number that receives according to conveying advocate control a process. Advocate the mass that charges a process to call signal effectiveness to judge module to judge signal, if think unqualified, adjust each parameter and remeasure. If judgement is qualification, call signal to handle module to undertake final signal handles the work, reach measure an outcome. 4 tests result is the medium that be measured with fine Huang Sha, undertook 45 times metrical. If the result pursues 4, 1 is shown. 4, 2 pursue for error statistic. Can see, most error appears inside the limits of 2 ～ 3cm. But do not show normal school. This and survey sample number still is concerned more not quite. 5 conclusion pass a large number of tests, the measurement technique that can think this kind is not contact completely is effective, feasible, it is the efficient way that settles complete blame contact to measure this one difficult problem. Prospective research still can experiment of pair of liquid medium measure, and raise a respect to spread out from what measure precision. CNC Milling CNC Machining