CN111879451A - Microcosmic acting force measuring system and method for judging contact zero point and surface property of microcosmic acting force measuring system - Google Patents
Microcosmic acting force measuring system and method for judging contact zero point and surface property of microcosmic acting force measuring system Download PDFInfo
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- 230000003287 optical effect Effects 0.000 claims abstract description 73
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- 238000005259 measurement Methods 0.000 claims abstract description 46
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- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
- G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
- G01L1/246—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre using integrated gratings, e.g. Bragg gratings
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Abstract
The invention discloses a microscopic acting force measuring system and a method for judging a contact zero point and surface properties of the microscopic acting force measuring system, wherein the measuring system comprises a sensing module, an optical sensing module, a demodulation light path module, a signal conditioning module, an upper computer module and a nanoscale precision micrometric displacement driving module, and can realize the measurement of microscopic interacting force of an interface in a micrometer scale; the method combines the correlated property of the interface microcosmic interaction force, can simply, quickly and accurately evaluate the position of the contact zero point of the probe microsphere and the measured surface, and thus can obtain more accurate pre-stroke variable information of the micro-nano measurement system; in addition, the force-separation displacement curve is obtained by measuring the microscopic interaction force of the measured surfaces of different materials and the interface of the probe microspheres with different characteristic sizes, and the surface property of the measured surface can be obtained by performing related treatment.
Description
Technical Field
The invention relates to micro-nano measurement and interface micro interaction force, in particular to a system for measuring force based on interface micro interaction force and a method for judging the contact zero point and the hydrophilic and hydrophobic characteristics of a measured surface.
Background
The micro-nano ultra-precise detection technology is a guarantee for ensuring that a micro device can be precisely processed and assembled, and is a premise and a basis for developing the nano processing technology. Three-coordinate measuring machines are often used for precisely measuring the three-dimensional size of some devices, and in order to measure micro devices, various micro probes and a measuring system for realizing nano-scale precision measurement by using a sensing principle are developed, the measuring force is small, and the diameter of the micro probe can reach the micron or nano level. When the diameter of the ball head of the microprobe reaches the micron or even nanometer level, when the tip of the microprobe is about to contact with the surface of the microdevice, a non-negligible interface microscopic interaction force can be generated between the tip of the measuring head and the measured surface, and the influence of the interface microscopic interaction force is much larger than the gravity.
When the nanometer three-coordinate micro measuring head measures the measured surface, no signal is output from the micro measuring head system at the moment when the measuring head contacts the measured surface, the minimum signal change output which can be sensed is generated from the moment when the measuring head contacts the measured surface to the micro measuring head, and a certain sensing distance exists, namely the pre-stroke change. Therefore, the output quantity of the actual micro probe measurement signal needs to introduce a pre-stroke variation for compensation and correction, but the pre-stroke variation has a close relationship with the instant position (i.e. the contact zero point) where the probe contacts the measured surface, and the accurate acquisition of the contact zero point directly affects the correction precision of the pre-stroke variation.
A precision switch circuit is designed in a equation to detect the position of a contact point, pre-travel measurement is realized, and an AFM force curve contact point estimation method based on a local regression algorithm is provided by Rafael Benitez. It can be seen that, at present, the measurement or acquisition of the contact zero point in the micro-nano measurement is obtained through a complex hardware design or algorithm, and the measurement or acquisition of the absolute contact zero point is physically impossible and can only be approached as much as possible by a sensing system or a signal analysis processing method with the highest sensitivity.
At present, for the measurement of hydrophilic and hydrophobic properties, contact angle measurement instruments are mostly used for measuring contact angles so as to obtain hydrophilic and hydrophobic properties, and the contact angle measurement instruments are expensive.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a microscopic acting force measuring system and a method for judging the contact zero point and the surface property of the microscopic acting force measuring system, so that the contact zero point and the surface property of the probe microsphere and the measured surface can be judged simply, quickly and accurately while the measurement of the microscopic acting force of the interface is realized.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention relates to a microcosmic acting force measuring system which is characterized by comprising the following components: the device comprises a sensing module, an optical sensing module, a demodulation light path module, a signal conditioning module, an upper computer module and a nanoscale precision micro-displacement driving module;
the sensing module comprises: the device comprises a machine body support of a measuring head, an ultra-precise stainless steel pipe, a measuring FBG sensor and a matching grating;
the measurement FBG sensor and the matched grating are respectively placed in the ultra-precise stainless steel pipe and are hung on the body support of the measuring head side by side; the fiber end face of the measuring FBG sensor is longer than the matching grating;
the optical sensing module includes: ASE broadband light source, first coupler;
the ASE broadband light source is connected with the input end of the first coupler, and the output end of the first coupler is connected with the measurement FBG sensor;
the demodulation optical path module comprises: a second coupler, a high sensitivity photodetector;
the input end of the second coupler is connected to the reflecting end of the first coupler, and the output end of the second coupler is connected to the matched grating; the high-sensitivity photoelectric detector is arranged at the reflection end of the second coupler;
the high-sensitivity photoelectric detector is connected to the signal conditioning module;
the host computer module includes: a data acquisition card and a computer;
the signal conditioning module is connected to a computer through the data acquisition card;
the nanometer precision micro-displacement driving module comprises: a digital voltage controller, a three-dimensional micro-motion platform and a one-dimensional nano micro-motion platform;
the input end of the digital voltage controller is connected to the computer, and the output end of the digital voltage controller is connected to the one-dimensional nanometer micro-motion platform;
the three-dimensional micro platform is provided with the one-dimensional nano micro platform;
the one-dimensional nanometer micro-motion platform is provided with a corresponding measured surface;
light emitted by the ASE broadband light source enters the measurement FBG sensor after passing through the first coupler, enters the matching grating from the second coupler after being reflected by the measurement FBG sensor, finally enters the high-sensitivity photoelectric detector after passing through the second coupler and outputs a light power voltage signal, and the area of the light power voltage signal is proportional to the area of the overlapped part of the reflection spectra of the measurement FBG sensor and the matching grating;
the signal conditioning module is used for preprocessing an optical power voltage signal and then sending the optical power voltage signal to the computer through the data acquisition card;
the computer calculates an average value of the received optical power voltage signals and carries out polynomial fitting by utilizing the average value so as to obtain a full-range voltage-distance curve; the voltage-distance curve is divided into three regions: a non-contact non-acting force area I, a non-contact interface microcosmic interaction force area II and a contact deformation area III; establishing an optical power voltage mean value-distance curve and an optical power voltage standard deviation-distance curve according to the preprocessed optical power voltage signals received from the data acquisition card, and finally judging the contact zero point of the probe microsphere of the FBG sensor to be measured and the surface to be measured according to the variation trends of the optical power voltage mean value-distance curve and the optical power voltage standard deviation-distance curve;
and the computer performs correlation processing on the received optical power voltage signals to obtain force-separation displacement curves of the probe microspheres with different measured surfaces and different characteristic sizes, performs normalization processing on the force-separation displacement curves to obtain normalized curves, and finally judges the properties of the measured surfaces according to the intersection point positions of the normalized curves.
The invention relates to a method for judging a contact zero point of a microcosmic acting force measuring system, which is characterized by comprising the following steps of:
and 5, returning to the step 2 after changing the size of the stepping delta x once, so as to obtain n groups of light power voltage mean value-distance curves and light power voltage standard deviation-distance curves, and judging the contact zero point of the probe microsphere of the FBG sensor to be measured and the surface to be measured according to the variation trends of the n groups of light power voltage standard deviation-distance curves and the light power voltage mean value-distance curves.
The invention relates to a method for judging surface properties based on a microcosmic acting force measuring system, which is characterized by comprising the following steps of:
and 4, repeating the step 2 and the step 3 to obtain force-separation displacement curves of the probe microspheres with different measured surfaces and different characteristic sizes, carrying out normalization processing to obtain a normalized curve, and judging the properties of the measured surface according to the intersection point position of the normalized curve.
Compared with the prior art, the invention has the beneficial effects that:
1. the interface microcosmic interaction force micro-nano measurement system is designed based on a fiber Bragg grating sensitive element and has a demodulation structure with temperature self-compensation and a high-resolution signal demodulation system. The measuring system is simple and reliable, and can realize nanoscale resolution, sensitivity and good stability; therefore, the measurement of the interface microscopic interaction force can be realized and the relevant properties can be analyzed;
2. according to the invention, the contact zero point of the probe microsphere and the measured surface is obtained, and the average value and the standard deviation of the obtained preprocessed optical power voltage signal are obtained by measuring the microscopic interaction force of the interface without additionally designing a complex hardware design or algorithm program, so that the contact zero point position of the probe microsphere and the measured surface can be simply, rapidly and accurately evaluated. Therefore, more accurate pre-stroke variable information of the micro-nano measurement system can be obtained through guidance;
3. the invention sets probe microspheres with different measured surfaces and different characteristic sizes and measures the interface microscopic interaction force to obtain a force-separation displacement curve and carry out normalization processing, and the hydrophilicity and hydrophobicity of the measured surface can be judged by analyzing the intersection point position of the normalization curve. According to the method, an expensive contact angle measuring instrument is not needed to measure the contact angle, and the related properties of the measured surface can be indirectly and accurately obtained by measuring the microscopic interaction force of the interface, so that a novel method for measuring the hydrophilicity and hydrophobicity of the unknown surface is provided, and the method has guiding significance for micro-nano measurement in different occasions.
Drawings
FIG. 1 is a schematic view of a measurement system according to the present invention;
FIG. 2a is a graph showing the results of the sensitivity test in the present invention;
FIG. 2b is a graph of a noise test signal according to the present invention;
FIG. 3 is a voltage-distance curve according to the present invention;
FIG. 4a is a graph of the optical power voltage mean-distance curve and the optical power voltage standard deviation-distance curve of the present invention, wherein the step size is 10 nm;
FIG. 4b is a graph of the optical power voltage mean-distance curve and the optical power voltage standard deviation-distance curve of the present invention, stepped by 2 nm;
FIG. 5a is a graph showing the results of testing probe microspheres of different feature sizes for a lens according to the present invention;
FIG. 5b is a graph of normalized test results for probe microspheres of different feature sizes for a lens of the invention;
FIG. 5c is a graph showing the results of testing probe microspheres of different characteristic sizes of the plastic of the present invention;
FIG. 5d is a graph of normalized test results for probe microspheres of different characteristic sizes of plastics according to the present invention;
FIG. 5e is a graph showing the test results of probe microspheres of different characteristic sizes of the aluminum sheet of the present invention;
FIG. 5f is a graph of normalized test results for probe microspheres of different characteristic sizes of the aluminum sheet of the present invention;
FIG. 6a is a graph of normalized simulation results for probe microspheres of different feature sizes for a lens of the invention;
FIG. 6b is a graph of the normalized simulation results of probe microspheres of different characteristic sizes of the plastic of the present invention;
FIG. 6c is a graph of normalized simulation results of probe microspheres of different characteristic sizes of the aluminum sheet of the present invention;
FIG. 6d is a view of the meniscus geometry of the probe microsphere of the present invention approaching the surface being measured.
Reference numbers in the figures: the device comprises a machine body support of a measuring head 1, an ultra-precise stainless steel pipe 2, a FBG (fiber Bragg Grating) sensor 3, a matching grating 4, an ASE (amplified spontaneous emission) broadband light source 5, a first coupler 6, a second coupler 7, a high-sensitivity photoelectric detector 8, a signal processing circuit 9, a data acquisition card 10, a computer 11, a digital voltage controller 12, a three-dimensional micro-motion platform 13 and a one-dimensional nano-micro-motion platform 14.
Detailed Description
In this embodiment, a system for measuring an interfacial microscopic interaction force on a micrometer scale is designed based on a fiber bragg grating sensing structure, and can simply, quickly and accurately obtain a contact zero point between a probe microsphere and a measured surface when measuring the interfacial microscopic interaction force, so as to accurately obtain a pre-stroke variation and correct the pre-stroke variation. As shown in fig. 1, the characteristics of the measuring system include: the device comprises a sensing module, an optical sensing module, a demodulation light path module, a signal conditioning module, an upper computer module and a nanoscale precision micro-displacement driving module;
the sensing module comprises: the device comprises a machine body support 1 of a measuring head, an ultra-precise stainless steel pipe 2, a measuring FBG sensor 3 and a matching grating 4; the FBG sensor 3 and the matched grating 4 are respectively placed in the ultra-precise stainless steel pipe 2 and are hung on the body support 1 of the measuring head side by side; the fiber end face of the measuring FBG sensor 3 is longer than the matching grating 4. In this embodiment, the FBG sensor 3 and the matching grating 4 are both single-mode FBGs, the bragg wavelength of which is 1550nm, the 3dB bandwidth is smaller than or close to 0.1nm, and the grating region length is 10 nm. In specific implementation, the FBG sensor 3 and the matching grating 4 are both arranged in the inner structure of the probe body support, and the end part of the optical fiber is led out. This form makes the FBG sensor 3 and the matching grating 4 can be approximately regarded as being placed in the same temperature field, and avoids the measurement error brought by the temperature change.
The optical sensing module comprises: an ASE broadband light source 5 and a first coupler 6; the ASE broadband light source 5 is connected to the input end of the first coupler 6, and the output end of the first coupler 6 is connected to the measurement FBG sensor 3. In this embodiment, the ASE broadband light source 5 has a working wavelength of 1525-1570nm and an output power of mW.
The demodulation optical path module comprises: a second coupler 7, a high-sensitivity photodetector 8; the input end of the second coupler 7 is connected to the reflection end of the first coupler 6, and the output end of the second coupler 7 is connected to the matching grating 4; the reflective end of the second coupler 7 is provided with a high sensitivity photodetector 8. In this embodiment, the first coupler 6 and the second coupler 7 are both 1 × 2 type 3dB couplers, and have an operating wavelength of 1550nm, an insertion loss of less than 3.6dB, and a wavelength range of ± 40 nm.
The high-sensitivity photoelectric detector 8 is connected to the signal conditioning module;
this host computer module includes: a data acquisition card 10 and a computer 11; the signal conditioning module is connected to a computer 11 via a data acquisition card 10.
The nanometer precision micro-displacement driving module comprises: a digital voltage controller 12, a three-dimensional micro-motion platform 13 and a one-dimensional nano micro-motion platform 14;
the input end of a digital voltage controller 12 is connected to the computer 11, and the output end of the digital voltage controller 12 is connected to a one-dimensional nanometer micro-motion platform 14; a one-dimensional nanometer micro-motion platform 14 is arranged on the three-dimensional micro-motion platform 13; the one-dimensional nano micro-motion platform 14 is provided with a corresponding measured surface. In this embodiment, the closed loop stroke of the one-dimensional nano micro-motion platform 14 is 2 μm, and the resolution is 0.03 nm.
Light emitted by the ASE broadband light source 5 enters the FBG sensor 3 after passing through the first coupler 6, enters the matched grating 4 from the second coupler 7 after being reflected by the FBG sensor 3, finally enters the high-sensitivity photoelectric detector 8 after passing through the second coupler 7 and outputs a light power voltage signal, and the light power voltage signal is proportional to the area of the overlapped part of the reflection spectrums of the FBG sensor 3 and the matched grating 4;
the signal conditioning module preprocesses the optical power voltage signal and then sends the optical power voltage signal to the computer 11 through the data acquisition card 10; in this embodiment, the signal conditioning module mainly performs preprocessing such as removing offset, amplifying, modulating, demodulating, filtering, and the like on the optical power voltage signal output by the high-sensitivity photodetector.
The computer 11 calculates the average value of the received preprocessed optical power voltage signals and performs polynomial fitting to obtain a full-range voltage-distance curve; the full-scale voltage-distance curve is divided into three regions: a non-contact non-acting force area I, a non-contact microscopic acting force area II and a contact deformation area III; establishing an optical power voltage mean value-distance curve and an optical power voltage standard deviation-distance curve according to the preprocessed optical power voltage signals received from the data acquisition card 10, and finally judging and measuring the contact zero point of the probe microsphere of the FBG sensor 3 and the measured surface according to the variation trends of the optical power voltage standard deviation-distance curve and the optical power voltage mean value-distance curve;
the computer 11 performs correlation processing on the received preprocessed optical power voltage signals to obtain force-separation displacement curves of the probe microspheres with different measured surfaces and different characteristic sizes, performs normalization processing to obtain a normalized curve, and finally judges the properties of the measured surface according to the intersection point position of the normalized curve.
In this embodiment, the measurement of system sensitivity and resolution is performed as follows:
to verify the sensitivity of the measurement system in this example, the one-dimensional nano micro-motion platform 14 is stepped by 20nm to make the measured surface approach the probe microsphere from the region i gradually until the measured surface contacts the probe microsphere and enters the region iii, the data acquisition card 10 acquires the optical power voltage signal of each step, and intercepts the optical power voltage signal at a distance of 200nm therefrom to perform data fitting, and the result is shown in fig. 2a, the slope of the fitting curve is 0.00622, i.e. the sensitivity is 6.22 mV/nm.
In order to verify the resolution of the measurement system in this example, the noise level of the measurement system needs to be measured, so that the probe microsphere and the measured surface are relatively static, the data acquisition card 10 acquires about 500 measurement data, and after 10-point smoothing filtering, as shown in fig. 2b, the noise level is about 18mV, theoretically, the ratio of the noise level to the sensitivity is about equal to the resolution, and therefore, the measurement resolution of the system obtained through calculation is 2.89 nm.
In summary, the measurement system is designed based on the fiber bragg grating sensitive element, has a temperature self-compensation demodulation structure and a high-resolution signal demodulation system, is simple and reliable, and can realize nanoscale resolution, sensitivity and good stability. When the system realizes the measurement of the microscopic interaction force, the contact zero point of the probe microsphere and the measured surface can be obtained only through simple data processing, and the property of the measured surface can be judged.
In this embodiment, a method for determining a zero point of contact based on an interface microscopic interaction force measurement system is performed as follows:
and 5, returning to the step 2 after changing the size of the stepping delta x once, so as to obtain n groups of light power voltage mean value-distance curves and light power voltage standard deviation-distance curves, and judging and measuring the contact zero point of the probe microsphere of the FBG sensor 3 and the measured surface according to the variation trends of the n groups of light power voltage mean value-distance curves and the light power voltage standard deviation-distance curves. FIG. 4a and FIG. 4b are graphs of mean value voltage-distance of light power voltage obtained by stepping Δ x at 10nm and 2nm, and standard deviation of light power voltage-distanceA wire. In connection with the measurements in the figure: the standard deviation of the optical power voltage of the non-contact interface microcosmic interaction force area II is obviously larger mainly due to the microcosmic interaction force area IIEach otherMechanical instability characteristics and uncertainty factors of the acting force; at the instant of zero contact point, the interface is microscopicEach otherThe acting force disappears, the stability caused by contact is obviously enhanced, and the standard deviation of the optical power and the voltage is also obviously reduced; in the contact deformation region iii, as the contact distance increases, the difference of stress release is caused by the influence of factors such as sensor deformation, the gap of the sensing package, and the positioning and mounting error of the sensing structure, and therefore, the optical power voltage standard deviation at this stage is increased by a large amount compared with the optical power voltage standard deviation near the contact zero point. Therefore, the acquisition of the contact zero reference point can be more accurately realized by combining the sharp change of the optical power voltage standard deviation data curve of the measurement result and the trend assistance of the measurement mean value.
3. A method for judging surface properties based on an interface microscopic interaction force measurement system is carried out according to the following steps:
and 4, repeating the step 2 and the step 3 to obtain force-separation displacement curves of different spherical diameters of different measured surfaces, carrying out normalization F/R (frequency/radiation) processing to obtain a normalized curve, and judging the properties of the measured surfaces according to the intersection point positions of the normalized curve. Fig. 5a, 5c and 5e are graphs of test results of probe microspheres with different feature sizes and with the surfaces to be tested of the lens, the plastic and the aluminum sheet, respectively, and fig. 5b, 5d and 5f are graphs of normalized test results of probe microspheres with different feature sizes and with the surfaces to be tested of the lens, the plastic and the aluminum sheet, respectively. As can be seen from fig. 5b, 5d and 5f, the normalized curves of the interfacial microscopic interaction forces of the probe microspheres with different feature sizes on the same measured surface are very close to each other, but the normalized curves of the two different sphere diameters on each measured surface generate an intersection point, and the intersection points of the surfaces of different materials are different from each other, the intersection point of the aluminum sheet is closest to the contact zero point, the intersection point of the plastic is next, and the lens is located at the intersection point farthest from the contact zero point. The expression for the micro-capillary force according to fig. 6d and the reference is:
in the formula (1), the reaction mixture is,
θ is the equivalent contact angle; gamma rayLIs the surface tension coefficient of the liquid; d is the separation distance of the sphere and the plane; v is the volume of the meniscus.
In this example, the normalized simulation result of the interfacial micro interaction force of the probe microspheres with different feature sizes, the surfaces of which are the lens, the plastic and the aluminum sheet, is shown in fig. 6a, fig. 6b and fig. 6c, where the parameter adjustment is only performed on the micro capillary force, and the other interaction forces are not changed. For the same measured surface, the larger the probe microsphere diameter is, the larger the geometric constraint condition in FIG. 5d is, the theta can be known2The larger the corresponding contact angle theta. In addition, the contact angle is different for different measured surfaces, and in the simulation curve, the contact angle of the aluminum sheet is set to be 36 degrees of a large sphere and 31 degrees of a small sphere,the contact angles of the plastic sheet were set to 47 ° for the large sphere and 41 ° for the small sphere, 56 ° for the large sphere and 50 ° for the small sphere. The positions of the intersections of the two curves in fig. 6a, 6b and 6c, which are about 60-70nm, 40-50nm and 15-20nm, respectively, have good agreement with the normalized experimental results in fig. 5b, 5d and 5 f. Therefore, the intersection point position of the normalized experimental curve shows that the hydrophilicity and hydrophobicity of the material can be known and quantified by using an interface microscopic interaction force measuring method, and the closer the intersection point position is to the contact zero point, the smaller the contact angle is, the more hydrophilic the measured surface is; conversely, the surface being measured is more hydrophobic. The method for measuring the microscopic interaction force of the interface can indirectly and accurately obtain the relevant properties of the surface to be measured, thereby providing a new method for measuring the hydrophilicity and hydrophobicity of an unknown surface and having guiding significance for micro-nano measurement in different occasions.
Claims (3)
1. A microscopic force measurement system, comprising: the device comprises a sensing module, an optical sensing module, a demodulation light path module, a signal conditioning module, an upper computer module and a nanometer precision micro-displacement driving module;
the sensing module comprises: the device comprises a machine body support (1) of a measuring head, an ultra-precise stainless steel pipe (2), a measuring FBG sensor (3) and a matching grating (4);
the measurement FBG sensor (3) and the matching grating (4) are respectively placed in the ultra-precise stainless steel pipe (2) and are hung on the body support (1) of the measuring head side by side; the fiber end face of the measuring FBG sensor (3) is longer than the matching grating (4);
the optical sensing module includes: an ASE broadband light source (5) and a first coupler (6);
the ASE broadband light source (5) is connected with the input end of the first coupler (6), and the output end of the first coupler (6) is connected with the measurement FBG sensor (3);
the demodulation optical path module comprises: a second coupler (7), a high-sensitivity photodetector (8);
the input end of the second coupler (7) is connected to the reflection end of the first coupler (6), and the output end of the second coupler (7) is connected to the matched grating (4); the reflection end of the second coupler (7) is provided with the high-sensitivity photoelectric detector (8);
the high-sensitivity photoelectric detector (8) is connected to the signal conditioning module;
the host computer module includes: a data acquisition card (10) and a computer (11);
the signal conditioning module is connected to a computer (11) through the data acquisition card (10);
the nanometer precision micro-displacement driving module comprises: a digital voltage controller (12), a three-dimensional micro-motion platform (13) and a one-dimensional nano micro-motion platform (14);
the input end of the digital voltage controller (12) is connected to the computer (11), and the output end of the digital voltage controller (12) is connected to the one-dimensional nanometer micro-motion platform (14);
the three-dimensional micro platform (13) is provided with the one-dimensional nano micro platform (14);
a corresponding measured surface is arranged on the one-dimensional nano micro-motion platform (14);
light emitted by the ASE broadband light source (5) enters the measurement FBG sensor (3) after passing through the first coupler (6), and enters the matching grating (4) from the second coupler (7) after being reflected by the measurement FBG sensor (3), and finally light reflected by the matching grating (4) enters the high-sensitivity photoelectric detector (8) after passing through the second coupler (7) and outputs a light power voltage signal which is proportional to the area of the overlapped part of the reflection spectrums of the measurement FBG sensor (3) and the matching grating (4);
the signal conditioning module is used for preprocessing an optical power voltage signal and then sending the optical power voltage signal to the computer (11) through the data acquisition card (10);
the computer (11) calculates an average value of the received light power voltage signals, and carries out polynomial fitting by using the average value so as to obtain a full-range voltage-distance curve; the voltage-distance curve is divided into three regions: a non-contact non-acting force area I, a non-contact interface microcosmic interaction force area II and a contact deformation area III; establishing an optical power voltage mean value-distance curve and an optical power voltage standard deviation-distance curve according to the preprocessed optical power voltage signals received from the data acquisition card (10), and finally judging the contact zero point of the probe microsphere of the FBG sensor (3) and the measured surface according to the variation trends of the optical power voltage mean value-distance curve and the optical power voltage standard deviation-distance curve;
and the computer (11) performs correlation processing on the received optical power voltage signals to obtain force-separation displacement curves of the probe microspheres with different measured surfaces and different characteristic sizes, normalizes the force-separation displacement curves to obtain normalized curves, and finally judges the properties of the measured surfaces according to the intersection point positions of the normalized curves.
2. A method for determining a zero point of contact of a microscopic force measuring system according to claim 1, comprising the steps of:
step 1, setting the stepping of the one-dimensional nanometer micro-motion platform (14) to be delta x;
step 2, adjusting the probe microspheres at the end parts of the FBG sensors (3) to be measured to be in a non-contact non-acting force area I of the measured surface, stepping the one-dimensional nanometer micro-motion platform (14) by delta x to enable the measured surface to gradually approach the probe microspheres, passing through an area II until the probe microspheres are contacted, entering an area III, and acquiring a plurality of preprocessed optical power voltage signals by using the data acquisition card (10) in the moving process of each step and sending the optical power voltage signals to the computer (11);
step 3, the computer (11) obtains the mean value of the optical power voltage signals of each step, and carries out polynomial fitting to obtain a full-range voltage-distance curve;
step 4, the computer (11) calculates the mean value and the standard deviation of the optical power voltage signal of each step, so as to obtain an optical power voltage standard deviation-distance curve and an optical power voltage mean value-distance curve;
and 5, returning to the step 2 after changing the size of the stepping delta x once, so as to obtain n groups of light power voltage mean value-distance curves and light power voltage standard deviation-distance curves, and judging the contact zero point of the probe microsphere of the FBG sensor (3) to be measured and the surface to be measured according to the variation trends of the n groups of light power voltage standard deviation-distance curves and the light power voltage mean value-distance curves.
3. A method for discriminating a surface property of a microscopic force measuring system according to claim 1, comprising the steps of:
step 1, setting probe microspheres with different measured surfaces and different characteristic sizes;
step 2, selecting a tested surface;
step 3, after a probe microsphere with a sphere diameter is selected, adjusting the probe microsphere at the end of the FBG sensor (3) to a non-contact interface microscopic interaction force area II, and enabling the one-dimensional nanometer micro-motion platform (14) to be in delta x form1In order to step, the detected surface is gradually close to the probe microsphere at the end part of the FBG sensor (3) until the detected surface is contacted with the probe microsphere, a plurality of preprocessed optical power voltage signals are acquired by the data acquisition card (10) in the moving process of each step and are sent to the computer (11), and the computer (11) carries out related processing to obtain a force-separation displacement curve;
and 4, repeating the step 2 and the step 3 to obtain force-separation displacement curves of the probe microspheres with different measured surfaces and different characteristic sizes, carrying out normalization processing to obtain a normalized curve, and judging the properties of the measured surface according to the intersection point position of the normalized curve.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112505143A (en) * | 2020-11-09 | 2021-03-16 | 南京大学 | Device and method for measuring interaction between macroscopic interfaces |
| CN113074841A (en) * | 2021-03-29 | 2021-07-06 | 合肥工业大学 | FBG probe system-based deformation sensitivity measuring method and interface force calibration method |
| CN113532285A (en) * | 2021-07-16 | 2021-10-22 | 合肥工业大学 | Micrometric displacement measurement system and method for picometer resolution |
| WO2023284592A1 (en) * | 2021-07-16 | 2023-01-19 | 合肥工业大学 | Micro-displacement measurement system having picometer scale resolution and measurement method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101003356A (en) * | 2007-01-12 | 2007-07-25 | 哈尔滨工业大学 | Method for making Nano microstructure based on constant height mode of atomic force microscope |
| CN201047823Y (en) * | 2006-12-22 | 2008-04-16 | 中国科学院沈阳自动化研究所 | Sample nondestructive approximation device for nano observation and operation |
| CN103278098A (en) * | 2013-06-06 | 2013-09-04 | 合肥工业大学 | Ultra-precision micro-displacement sensing system and processing method based on double-FBG suspended type probe structure |
| CN203310858U (en) * | 2011-08-30 | 2013-11-27 | 长春理工大学 | Measuring system based on detection of reference model having nanometer surface microstructure |
| CN106443218A (en) * | 2016-11-24 | 2017-02-22 | 电子科技大学 | Surface charge measurement method |
| CN106441095A (en) * | 2016-09-14 | 2017-02-22 | 合肥工业大学 | Bragg grating based nano three-dimensional micro probe measuring system and measuring method |
| CN107966121A (en) * | 2017-10-19 | 2018-04-27 | 合肥工业大学 | A kind of microballoon sphericity high-accuracy measurement control system based on LabVIEW |
-
2020
- 2020-07-30 CN CN202010750525.2A patent/CN111879451B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201047823Y (en) * | 2006-12-22 | 2008-04-16 | 中国科学院沈阳自动化研究所 | Sample nondestructive approximation device for nano observation and operation |
| CN101003356A (en) * | 2007-01-12 | 2007-07-25 | 哈尔滨工业大学 | Method for making Nano microstructure based on constant height mode of atomic force microscope |
| CN203310858U (en) * | 2011-08-30 | 2013-11-27 | 长春理工大学 | Measuring system based on detection of reference model having nanometer surface microstructure |
| CN103278098A (en) * | 2013-06-06 | 2013-09-04 | 合肥工业大学 | Ultra-precision micro-displacement sensing system and processing method based on double-FBG suspended type probe structure |
| CN106441095A (en) * | 2016-09-14 | 2017-02-22 | 合肥工业大学 | Bragg grating based nano three-dimensional micro probe measuring system and measuring method |
| CN106443218A (en) * | 2016-11-24 | 2017-02-22 | 电子科技大学 | Surface charge measurement method |
| CN107966121A (en) * | 2017-10-19 | 2018-04-27 | 合肥工业大学 | A kind of microballoon sphericity high-accuracy measurement control system based on LabVIEW |
Non-Patent Citations (2)
| Title |
|---|
| 朱正恺等: "基于光纤光栅新型微位移测量方法研究", 《仪表技术与传感器》 * |
| 朱肃然等: "基于布拉格光纤光栅的微位移传感器的研究", 《工具技术》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112505143A (en) * | 2020-11-09 | 2021-03-16 | 南京大学 | Device and method for measuring interaction between macroscopic interfaces |
| CN112505143B (en) * | 2020-11-09 | 2022-06-21 | 南京大学 | Device and method for measuring interaction between macroscopic interfaces |
| CN113074841A (en) * | 2021-03-29 | 2021-07-06 | 合肥工业大学 | FBG probe system-based deformation sensitivity measuring method and interface force calibration method |
| CN113532285A (en) * | 2021-07-16 | 2021-10-22 | 合肥工业大学 | Micrometric displacement measurement system and method for picometer resolution |
| CN113532285B (en) * | 2021-07-16 | 2022-07-12 | 合肥工业大学 | Micrometric displacement measurement system and method for picometer resolution |
| WO2023284592A1 (en) * | 2021-07-16 | 2023-01-19 | 合肥工业大学 | Micro-displacement measurement system having picometer scale resolution and measurement method |
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