CN202770526U - Mechanical vibration amplitude curve measurement system - Google Patents

Mechanical vibration amplitude curve measurement system Download PDF

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Publication number
CN202770526U
CN202770526U CN 201220258499 CN201220258499U CN202770526U CN 202770526 U CN202770526 U CN 202770526U CN 201220258499 CN201220258499 CN 201220258499 CN 201220258499 U CN201220258499 U CN 201220258499U CN 202770526 U CN202770526 U CN 202770526U
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high speed
linear array
array ccd
measurement
mechanical vibration
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CN 201220258499
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Chinese (zh)
Inventor
孙建华
袁科
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Xian Huanic Optoelectronic Corp Ltd
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Xian Huanic Optoelectronic Corp Ltd
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Abstract

The utility model belongs to the technical field of laser measurement, and provides a mechanical vibration amplitude curve measurement system. The system comprises a horizontal straight line laser module; collection boxes arranged on an emergent light path of the horizontal straight line laser module and mainly used for receiving a PC machine command, and a control box for controlling the collection boxes, transferring data and managing a power supply, wherein the collection boxes are sequentially arranged on plan measurement points on the measurement axle of the system to be measured and in an approximate straight line, and measurement points of photosensitive surfaces of high speed array CCDs of the collection boxes are prevented from mutually shielding the received laser; the problems of the existing mechanical vibration amplitude curve measurement system such as bad precision and low response efficiency are solved; and the mechanical vibration amplitude curve measurement system of the utility model has features of relatively simple structure and light path, relatively high measurement response frequency, precise measurement of amplitude value, simple installation and easy operation.

Description

A kind of amplitude curve measuring system of mechanical vibration
Technical field
The utility model belongs to laser measuring technique, relates to a kind of non-contact laser measuring technique, specifically a kind of amplitude curve measuring system of mechanical vibration.
Background technology
To the amplitude curve measuring method of mechanical vibration, mostly be non-contact measurement at present, adopt line array CCD to measure more, but the amplitude precision of its measuring vibrations is relatively poor, because the impact of photoelectric device and electronic system, the response frequency of its measuring vibrations is lower, and structure and optical system are comparatively complicated.
The utility model content
The purpose of this utility model is the existing low precision of amplitude curve measuring method and system and the low problem of response frequency that solves the existing machinery vibration.
For reaching above-mentioned purpose, the utility model provides a kind of amplitude curve measuring method of mechanical vibration, may further comprise the steps:
1), sets the primary standard value;
2), data acquisition;
3), data are preserved and zero clearing.
Above-mentioned steps 1) implementation procedure is:
1.1), away from the Gu Bi of test macro one word line laser module is being installed;
1.2), the plan measurement point on the measurement axis of tested system sets gradually a plurality of collecting cassettes, this plan measurement point is near linear along this measurement axis and distributes, and avoids the measuring point of light-sensitive surface of the high speed linear array CCD of these a plurality of collecting cassettes to block mutually the light of reception;
1.3), a word laser beam of word line laser module emission shone simultaneously in the measuring point zone of high speed linear array CCD of each collecting cassette, the laser light signal that this high speed linear array CCD will be beaten on its light-sensitive surface is converted into electric signal, and this electric signal transmission is amplified to amplifying circuit; Electric signal after the amplification is by shaping and digital processing circuit, be digital signal with analog signal conversion, and with this digital data transmission to programmable device FPGA, realize that this programmable device FPGA is to the driving of this high speed linear array CCD and the real-time calculating of incident light center, and result of calculation stored among the large capacity SDRAM, utilize simultaneously programmable device FPGA to realize the driving of MAX485 chip, and by the RS485 bus last result of calculation is transferred to control enclosure, by this control enclosure last result of calculation is uploaded to PC and preserves, finish collection and the setting of primary standard value.
Above-mentioned steps 2) implementation procedure is:
When tested system is subjected to vibration, installed surface sedimentation or external force generation deformation, one word laser beam can change in the position of the light-sensitive surface of high speed linear array CCD measurement point, this high speed linear array CCD gathers 5000 word laser beam in the positional information of the light-sensitive surface of high speed linear array CCD measurement point with per second, and this positional information is converted into electric signal exports to the amplification that amplifying circuit carries out signal; Electric signal after the amplification is by shaping and digital processing circuit, be digital signal with analog signal conversion, and with this digital data transmission to programmable device FPGA, by this programmable device FPGA this digital signal is calculated in real time, and result of calculation stored among the large capacity SDRAM, by the RS485 bus last result of calculation is transferred to control enclosure simultaneously, by this control enclosure last result of calculation is uploaded to PC, thereby finish data acquisition.
Above-mentioned steps 3) implementation procedure is: PC will be from the next data of described control enclosure transmission, classification is saved in each txt document, and draw out the mechanical vibration amplitude curve, realize simultaneously the data zero clearing, this data zero clearing refers to all data that collect are deducted described primary standard value; Data herein refer to be transferred to by control enclosure the last result of calculation of this PC.
Simultaneously, the utility model also provides a kind of amplitude curve measuring system of the mechanical vibration based on aforementioned measuring method, this system comprises a word line laser module, be arranged on the collecting cassette on the emergent light light path of this word line laser module, mainly finish the reception of PC order and to the control of this collecting cassette, the control enclosure of the transmission of data and the management of power supply, described collecting cassette is a plurality of, plan measurement point on the measurement axis of tested system sets gradually, and lineal layout, and avoid the measuring point of light-sensitive surface of the high speed linear array CCD of these a plurality of collecting cassettes to block mutually the laser of reception; Described collecting cassette comprises high speed linear array CCD, programmable device FPGA and storer, amplifying circuit and shaping and digital processing circuit, and this high speed linear array CCD, storer are electrically connected with programmable device FPGA respectively; Described high speed linear array CCD will be beaten laser light signal on its light-sensitive surface and be converted into electric signal and this electric signal transmission is amplified to described amplifying circuit; Electric signal after the amplification is digital signal by shaping and digital processing circuit with analog signal conversion; And this digital signal sent into programmable device FPGA, by this programmable device FPGA this digital signal is calculated in real time, and result of calculation stored in the described storer, by the RS485 bus last result of calculation is transferred to control enclosure simultaneously, by this control enclosure last result of calculation is uploaded to PC.
Above-mentioned high speed linear array CCD is selected the high speed linear array CCD of Toshiba--TCD2703D, described programmable device FPGA adopts EP1C6T144C6, described storer adopts SDRAM, and described control enclosure adopts MSP430F247, and described control enclosure is connected with described PC by the USB mouth; Described amplifying circuit mainly is made of transport and placing device and high speed analogue selector, and described shaping and digital processing circuit mainly are made of comparer.
Above-mentioned transport and placing device adopts AD8011AN, and the high speed analogue selector adopts 74hc4051, and comparer adopts AD8561.
The utility model has the advantages that: system architecture and light path are comparatively simple, measure response frequency higher, and the measuring amplitude value is accurate; Simple easy operating is installed.
Description of drawings
Below with reference to accompanying drawing the utility model is described in further details:
Fig. 1 is the structural representation of the amplitude curve measuring system of the mechanical vibration that provide of the utility model.
Among the figure: 1, a word line laser module; 2, collecting cassette; 3, control enclosure; 4, PC; 5, tested system; 6, laser; 7, Gu Bi.
Embodiment
In order to solve the existing low precision of amplitude curve measuring method and the low problem of response frequency of existing machinery vibration, the present embodiment provides a kind of amplitude curve measuring method of mechanical vibration, may further comprise the steps:
1), sets the primary standard value;
2), data acquisition;
3), data are preserved and zero clearing.
Wherein, the implementation procedure of step 1) is:
1.1), away from the Gu Bi of test macro one word line laser module is being installed;
1.2), the plan measurement point on the measurement axis of tested system sets gradually a plurality of collecting cassettes, this plan measurement point is near linear along this measurement axis and distributes, and avoids the measuring point of light-sensitive surface of the high speed linear array CCD of these a plurality of collecting cassettes to block mutually the light of reception;
1.3), a word laser beam of word line laser module emission shone simultaneously in the measuring point zone of high speed linear array CCD of each collecting cassette, the laser light signal of this high speed linear array CCD air exercise on its light-sensitive surface is converted into electric signal and exports to the amplification that amplifying circuit carries out signal; Electric signal after the amplification is by shaping and digital processing circuit, be digital signal with analog signal conversion, and with this digital data transmission to programmable device FPGA, realize that this programmable device FPGA is to the driving of this high speed linear array CCD and the real-time calculating of incident light center, and result of calculation stored among the large capacity SDRAM, utilize simultaneously programmable device FPGA to realize the driving of MAX485 chip, and by the RS485 bus last result of calculation is transferred to control enclosure, by this control enclosure last result of calculation is uploaded to PC and preserves, finish collection and the setting of primary standard value.
Step 2) implementation procedure is:
When being subjected to the cause influences such as vibration, installed surface sedimentation, external force generation deformation when tested system, one word laser beam can change in the position of the light-sensitive surface of high speed linear array CCD measurement point, this high speed linear array CCD gathers 5000 word laser beam in the positional information of the light-sensitive surface of high speed linear array CCD measurement point with per second, and this positional information is converted into electric signal exports to the amplification that amplifying circuit carries out signal; Electric signal after the amplification is by shaping and digital processing circuit, be digital signal with analog signal conversion, and with this digital data transmission to programmable device FPGA, by this programmable device FPGA this digital signal is calculated in real time, and result of calculation stored among the large capacity SDRAM, by the RS485 bus last result of calculation is transferred to control enclosure simultaneously, by this control enclosure last result of calculation is uploaded to PC, thereby finish data acquisition.
The implementation procedure of step 3) is: PC will be from the next data of described control enclosure transmission, classification is saved in each txt document, and draw out the mechanical vibration amplitude curve, realize simultaneously the data zero clearing, this data zero clearing refers to all data that collect are deducted described primary standard value; Data herein refer to be transferred to by control enclosure the last result of calculation of this PC.
Simultaneously, the utility model also provides the amplitude curve measuring system of mechanical vibration based on aforementioned measuring method shown in Figure 1, this system comprises when a word line laser module 1(uses on the solid wall 7 that it is installed in away from test macro), be arranged on the collecting cassette 2 on the emergent light light path of this word line laser module 1, mainly finish the reception of PC 4 order and to the control of this collecting cassette 2, the control enclosure 3 of the transmission of data and the management of power supply, collecting cassette 2 comprises high speed linear array CCD, programmable device FPGA and storer, amplifying circuit and shaping and digital processing circuit, this high speed linear array CCD, storer is electrically connected with programmable device FPGA respectively; Laser 6 light signals that high speed linear array CCD will be beaten on its light-sensitive surface are converted into electric signal and this electric signal transmission are carried out the amplification of signal to described amplifying circuit; Electric signal after the amplification is digital signal by shaping and digital processing circuit with analog signal conversion; And this digital signal sent into programmable device FPGA, by this programmable device FPGA this digital signal is calculated in real time, and result of calculation stored in the storer, by the RS485 bus last result of calculation is transferred to control enclosure 3 simultaneously, by this control enclosure 3 last result of calculation is uploaded to PC 4.
Collecting cassette 2 is a plurality of, plan measurement point on the measurement axis of tested system 5 sets gradually, this plan measurement point is near linear along this measurement axis and distributes, and avoids the measuring point of light-sensitive surface of the high speed linear array CCD of these a plurality of collecting cassettes 2 to block mutually the light of reception.
Wherein, high speed linear array CCD is selected the high speed linear array CCD of Toshiba--TCD2703D, and described programmable device FPGA adopts EP1C6T144C6, and described storer adopts SDRAM, described control enclosure adopts MSP430F247, and described control enclosure is connected with described PC by the USB mouth; Described amplifying circuit mainly is made of transport and placing device and high speed analogue selector, and described shaping and digital processing circuit mainly are made of comparer.
Wherein, transport and placing device adopts AD8011AN, and the high speed analogue selector adopts 74hc4051, and comparer adopts AD8561.
Above-mentioned high speed linear array CCD is selected the high speed linear array CCD of Toshiba--TCD2703D, described programmable device FPGA adopts EP1C6T144C6, described storer adopts SDRAM, and described control enclosure adopts MSP430F247, and described control enclosure is connected with described PC by the USB mouth; Described amplifying circuit mainly is made of transport and placing device and high speed analogue selector, and described shaping and digital processing circuit mainly are made of comparer.
High speed linear array CCD in the native system is selected the high speed linear array CCD of Toshiba--TCD2703D, and the maximum scan speed that this high speed linear array CCD can be supported is 4.05us+ (7500+142)/(2*25) us=156.89us, i.e. 6.37k.When single-chip microcomputer scanned CCD with 5K speed control FPGA, FPGA still can have 200us-156.89us=43.11us to carry out other data processing.Adopt this CCD can realize 5000 data acquisitions of per second fully.The picture dot point of this CCD is apart from be 9.325us, totally 7500 effective picture dot points, and native system adopts its odd-numbered line output to carry out computing, and picture dot point distance is 9.325um*2=18.65um, and measuring accuracy can reach micron order; Giving the FPGA digital processing system is 18.65um*5=93.26um to the error in judgement of 5 orders of magnitude of laser signal, namely can reach at least the measuring accuracy of 0.093mm.The total length of this CCD is 7500*9.325=69937.5us=69.9375mm, measurement range is about ± 35mm, considers that there is the live width of 1~2mm in laser instrument itself, for guaranteeing the accuracy of measurement data, the native system measurement range is decided to be ± 30mm, this shows that native system has higher measuring accuracy.
The programmable device FPGA of native system is selected EP1C6T144C6, and this chip internal operating rate reaches as high as 166MHz, can satisfy the driving of CCD and processing, calculating and the storage of output signal digital signal.We also utilize TCD2703D to the response characteristic of red bluish-green three road light, different to the decay of the one-wavelength laser of different colours, have realized the accurate extraction of the center of the linear laser signal under the light intensity on a large scale.By the FPGA program, realized the identification to three kinds of light paths, and select one tunnel light path that is best suited for the compute ray center from three tunnel light paths, adjustment automatically gains, make this light path characteristic reach best design conditions, thereby so that become more accurate calculated in the center.
Signal amplifies: when the sweep speed that adopts 25MHz drives CCD, the fundamental frequency of ccd output signal is 25MHz/0.4=62.5MHz, consider 4 times of amplifications, the gain-bandwidth product that then needs is the above amplifier of 250MHz, and this case is selected the amplifier of the AD8011AN of 300MHz.Because consider that the collecting cassette riding position is different, or adopt different word laser line generators, the strong and weak difference of the laser rays signal that collects is carried out the automatic gain regulation and control therefore adopt to the control of high speed analogue selector 74hc4051.Utilize FPGA that the automatic gain regulation and control are carried out in the control of high speed analogue selector 74hc4051.This analogue selector can be by the signal more than the 145MHz when 5V powers.
Shaping and digital processing circuit: through the signal after amplifying, can be by being sent to FPGA after the AD sampling, but the degree of distortion of like that signal being amplified requires high, must guarantee that AD sampling device signal is steady, namely to guarantee undamped the passing through of 3 frequencys multiplication of signal, then this moment long-pending requirement of amplifier band width gain become 62.5*3*4=750MHz, this kind amplifier is too expensive, and circuit is not easy design.After passing through high-speed comparator by the ccd signal after will amplifying, directly deliver to FPGA for this reason, by setting comparison threshold and digital signal processing, determine the edge of light.The response speed of comparer need to be greater than 1/62.5MHz=16ns, and this case is selected the 7ns comparer AD8561 of AD company.
Data storages (SDROM): each slave computer per second need to be stored 5k some data, and the span of each some data is-30.9 to 30.9, and the relation of the data x of storage and real data y is as follows:
X=(y+30.9) * 10, y=x/10-30.9, the maximal value of X is 618, need to adopt 2 bytes store, so 10 seconds needs storage 5kword*10s=50kword data, consider the from now on expansion requirement of system, can adopt the KM416S1120D high speed SDRAM chip of 512k*16bit*2banks, this chip can be stored the 512*2/50=200s data at most.
Control enclosure is mainly finished the reception of PC order and to the control of each collecting cassette, the transmission of data and the management of power supply.Control enclosure adopts MSP430F247 as primary controller, utilizes the USB mouth to communicate by letter with PC, to guarantee the high-speed transfer of data; Utilize simultaneously the RS485 bus to communicate by letter with collecting cassette.Collector is after " begin gather " order that receives control enclosure, by high-resolution timer timing acquiring separately.Because sampling rate is up to 5KHz, establishing clock accuracy is that 1ppm(is per second skew 1us), then interior each the collector sampling clock peak excursion of 100s is poor is 0.2ms, less than a sampled point, can guarantee the accurate synchronous acquisition of each collecting cassette.
The application software of PC is responsible for receiving the data that the single-chip microcomputer transmission comes, and this Data classification is saved in each txt document.And draw just amplitude curve, and utilize the application software of PC to realize " zero clearing " function (record standard value, and the data that all collect are deducted this standard value of data.The data of txt document storing are the data after raw data deducts standard value).System adopts triggering mode to carry out high-speed synchronous collection storage, gather finish after, again with the data transmission that collects to PC.There are two kinds of triggering collection modes in system, and a kind of is that software triggers, and another kind is hardware trigger, so that the synchronous acquisition during experiment.
The acquisition rate of this each collecting cassette of system can be selected at 500Hz, 1KHz, 2.5KHz, 5KHz, and sampling time length can be selected between 5s~100s, and the collecting cassette number can be selected between 1-16.When the linear laser device is fixed, each collecting cassette and measured position be fixedly the time, the displacement of can high-speed synchronous measuring each measured position, and precision can reach ± 0.1mm.
In sum, native system has structure and light path is simple, measures response frequency higher, and the measuring amplitude value is accurate; The advantage of simple easy operating is installed.
More than exemplifying only is to illustrate of the present utility model, does not consist of the restriction to protection domain of the present utility model, and the every and same or analogous design of the utility model all belongs within the protection domain of the present utility model.

Claims (3)

1. the amplitude curve measuring system of mechanical vibration, it is characterized in that: comprise a word line laser module, be arranged on the collecting cassette on the emergent light light path of this word line laser module, mainly finish the reception of PC order and to the control enclosure of the management of the transmission of the control of this collecting cassette, data and power supply;
Described collecting cassette is a plurality of, and the plan measurement point on the measurement axis of tested system sets gradually, and lineal layout, and avoids the measuring point of light-sensitive surface of the high speed linear array CCD of these a plurality of collecting cassettes to block mutually the laser of reception;
Described collecting cassette comprises high speed linear array CCD, programmable device FPGA and storer, amplifying circuit and shaping and digital processing circuit, and this high speed linear array CCD, storer are electrically connected with programmable device FPGA respectively; The laser light signal that described high speed linear array CCD will be beaten on its light-sensitive surface is converted into electric signal, and amplifies to described amplifying circuit this electric signal transmission; Electric signal after the amplification is digital signal by shaping and digital processing circuit with analog signal conversion; And this digital signal sent into programmable device FPGA, by this programmable device FPGA this digital signal is calculated in real time, and result of calculation stored in the described storer, by the RS485 bus last result of calculation is transferred to control enclosure simultaneously, by this control enclosure last result of calculation is uploaded to PC.
2. the amplitude curve measuring system of mechanical vibration as claimed in claim 1, it is characterized in that: described high speed linear array CCD is selected the high speed linear array CCD-TCD2703D of Toshiba, described programmable device FPGA adopts EP1C6T144C6, described storer adopts SDRAM, described control enclosure adopts MSP430F247, and described control enclosure is connected with described PC by the USB mouth; Described amplifying circuit mainly is made of transport and placing device and high speed analogue selector, and described shaping and digital processing circuit mainly are made of comparer.
3. the amplitude curve measuring system of mechanical vibration according to claim 2 is characterized in that: described transport and placing device employing AD8011AN, high speed analogue selector employing 74hc4051, comparer employing AD8561.
CN 201220258499 2011-12-01 2012-06-04 Mechanical vibration amplitude curve measurement system Expired - Fee Related CN202770526U (en)

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Application Number Priority Date Filing Date Title
CN 201220258499 CN202770526U (en) 2011-12-01 2012-06-04 Mechanical vibration amplitude curve measurement system

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Application Number Priority Date Filing Date Title
CN201120492436 2011-12-01
CN201120492436.9 2011-12-01
CN 201220258499 CN202770526U (en) 2011-12-01 2012-06-04 Mechanical vibration amplitude curve measurement system

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018233278A1 (en) * 2017-06-20 2018-12-27 福州大学 Apparatus and method for simultaneous measurement of three-dimensional vibration of rotary shaft
CN109682356A (en) * 2019-01-24 2019-04-26 成都大亦科技有限公司 Automatic measurement mechanism based on laser datum face

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018233278A1 (en) * 2017-06-20 2018-12-27 福州大学 Apparatus and method for simultaneous measurement of three-dimensional vibration of rotary shaft
CN109682356A (en) * 2019-01-24 2019-04-26 成都大亦科技有限公司 Automatic measurement mechanism based on laser datum face
CN109682356B (en) * 2019-01-24 2024-03-22 成都大亦科技有限公司 Automatic measuring device based on laser reference plane

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C17 Cessation of patent right
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Granted publication date: 20130306

Termination date: 20130604