Method for contactless detection of surface roughness parametres and device for its realisation
FIELD: physics, measurement.
SUBSTANCE: invention may be used for contactless detection of quality in items having medium and low classes of purity. Detection of surface roughness parametres is carried out by digital survey of investigated surface or its area by digital optical device with resolution of at least 3 megapixels at angle of illumination of 15°, 45°, 75° with normal location of lens to investigated surface. Digital pictures are sent to computer, pictures are processed and analysed on the basis of calculation of statistical criteria of each picture. Mean-square deviation is found between statistical criteria, which is correlated with arithmetical mean deviation of roughness sample Ra. Restoration coefficient k is determined. Electronic model of surface microrelief is built by transformation of picture pixels into three-dimensional coordinates, which are used for calculation of geometric parametres of surface roughness.
EFFECT: higher efficiency of surface roughness parametres measurement.
2 cl, 14 dwg, 8 tbl
The invention relates to the field of instrumentation and optical digital devices and can be used for contactless determination of quality products with medium and low classes purity of the processed surfaces within Ra=0,8÷100 μm. Can be used both in laboratory and industrial conditions, i.e. with significant vibrations and partial contamination of the surface, as well as automated surface quality control and adaptive control of technological process.
Known non-contact method of determining the quality of the surface based on the measurement of the intensity of specular and diffuse component of the reflected from the object surface radiation (US 3771880 And 13.11.1973).
A common feature of the known method with the inventive method is that it is aimed at solving similar tasks.
The disadvantage of this method is the low speed of the definition of controlled roughness parameters, limited sequential scan lines, and not taking into account the instability of the radiation source over time, which lowers the accuracy of measuring the quality of a surface.
Known non-contact method of measuring the surface quality (DE 3626724 AND 11.02.1988), based on the filing of a monochromatic light beam on a surface is the motion of the object to retrieve the specular and diffuse component reflected from the surface of the object light beam, converting reflected from the object surface specular and diffuse component of the light into a photocurrent, their submission for further processing device converting light into a photocurrent.
The disadvantage of this technical solution is low, the speed of scanning the sample surface, high sensitivity to contamination of the surface being examined and vibration, and reduced measurement accuracy due to the lack of instability compensation intensity of the probing radiation in time.
The known method of surface quality control implemented in the device (EN 2104480 C1, G01B 11/30, 10.02.1998), including the filing of a monochromatic light beam on the surface of the object to retrieve the specular and diffuse component reflected from the surface of the object light beam, receiving light pulses of equal duration from the received component, the formation of the reference light pulses corresponding to the pulses obtained from specular and diffuse component reflected from the surface of the object light beam, in pairs alternately converting each light pulse obtained from specular and diffuse components reflected from the object surface light emission with a corresponding reference light pulse is om, in the photocurrent and the subsequent determination of the surface quality of the object taking into account the adjustment of the intensities of light pulses obtained from specular and diffuse component reflected from the surface of the object light beam, the intensities of the corresponding reference light pulses.
The disadvantage of this method is not taking into account the instability of the radiation source over time, which lowers the accuracy of measuring the quality of a surface.
For the prototype accepted method EN 2249787 C1, G01B 11/30, 10.04.2005. Common features with the inventive method are: General purpose - determination of roughness parameters of the surface.
The known device for surface quality control (EN 2104480 C1, G01B 11/30, 10.02.1998) contains a source of monochromatic beam of light radiation applied to the surface of the object, the beam-splitting plate, installed at the outlet of a source of monochromatic beam of light radiation, the mirror in the form of a paraboloid of revolution with an inlet and outlet, the focus of which is located on the optical axis of the beam of light radiation and combined with the surface of the object, the focusing system installed opposite the reflective surface of the mirror, the first photodetector placed in front of the focusing system, the output of which is connected to the control unit and the processing of information, the first seal with window and mirror area on the surface of a rotating disk mounted in front of the first photodetecting device and connected to the control unit and processing information, and the first and second mirror, wherein the mirror component reflected from an object light beam is optically interfaced with the input of the first photodetecting device through the hole of the mirror in the form of a paraboloid of rotation, the first and second mirrors and mirror area of a rotating disk of the first surface and the diffuse component of the reflected from the surface of the object light beam is optically interfaced with the input of the first photodetecting device via the reflecting mirror surface in the form of a paraboloid of rotation of the focusing system and the window of a rotating disk the first obturator.
The disadvantage of the above technical solution is a low speed define the parameters of the roughness of the entire surface or area, high sensitivity to contamination of the surface being examined and vibrations, as a consequence of limited use in the composition of the automated surface quality control and adaptive control of technological processes, as well as reduced accuracy and surface quality control, due to the fact that the pulses specular and diffuse with the bringing reflected from the object radiation and the corresponding reference pulses for adjusting the intensities are allocated from different parts of the curve" change the intensity of the light radiation source in time and the change of intensity in real terms is non-linear, which leads to large errors in the adjustment of the intensities.
For the prototype accepted device for surface quality control (EN 2249787 C1, G01B 11/30, 10.04.2005).
The drawbacks of the prototype are: low speed determine the roughness parameters of the surface; it is not possible to determine the quality of the entire surface or area, as the prototype of selectively scanning a limited number of pixels; high sensitivity to contamination of the surface being examined and vibration; determining one of the roughness parameter Rq does not give a complete picture of the quality of the surface; it is impossible to use in a production environment; as a consequence, limited use in the composition of the automated surface quality control and adaptive control of technological process.
The claimed invention is directed to solving the problem of the creation of such techniques and apparatus for contactless determination of parameters of surface roughness, which could be the basis of the adaptive management process, i.e. the system is able to quickly identify defective areas of the surface and in real-time ADJ is its technological process of processing without changing the conditions of the home of the workpiece.
The technical result consists in increasing the efficiency measurements of the surface roughness at ten times compared with laser profilometry and the other used for this purpose methods while ensuring high accuracy of measurement.
The technical result of the invention is a high performance information about the state of the surface microrelief, the possibility of further computer analysis of the topography and surface properties for different research purposes, the system of automated control of the surface quality, the ability to work as part of the adaptive process control, diagnostics processing defects, improving the reliability of testing results.
The technical result is achieved by the fact that the used method for the contactless determination of parameters of surface roughness, which consists in conducting digital photography investigated surface or her section through a digital optical device with a minimum resolution of 3 megapixels at angles of illumination 15°, 45°, 75° with the normal lens digital optical unit relative to the sample surface, the transmission of digital images in the electronic computer, the process is TKE images for further analysis and definition, two-dimensional and three-dimensional roughness parameters of the surface, while the analysis of the processed images is performed on the basis of the calculation of the statistical characteristics of each digital image, find the standard deviation between the calculated statistical characteristics of the obtained standard deviation is correlated with the arithmetical mean deviation Ra of the sample roughness or pattern parts made from the same material as measured item, determine the coefficient of restitution k=Ra/M(Δx), where M(Δx)is the expectation of the deviation of the pixel intensity of the analyzed image; Ra - arithmetical mean deviation of profile details, build electronic model of the surface microrelief by converting the pixels of the picture xiin the three-dimensional coordinates x, y and z, which are used to calculate the altitude and walking roughness parameters of the surface, with coordinates x and y define here the position of a pixel in millimeters, and the z coordinate defines the height of a pixel in micrometers.
The technical result is achieved by the fact that the applied device for contactless determination of roughness parameters of the surface containing the optical digital device in a digital camera, at least three directional light source and electronnuclear machine, moreover, optical digital device is located properly with respect to the sample surface, and directional light sources mounted on tripods at angles of 15°, 45°, 75°, which allows you to create lighting without glare, while the digital camera is connected to the electronic computing machine via the USB interface. Universal Serial Bus is a universal serial bus is an industry standard expansion of computer architecture-centric integration with digital peripherals. The USB interface connects the host and digital peripherals through a 4-wire cable: power +5 V, the signal line D+ and D-, the common wire. The host is inside the computer and controls the operation of the entire interface. The transmission speed of more than 12 Mbit/s USB interface is designed to control the digital camera and transfer of digital images in the computer.
The inventive method is based on theory Beckmann, in accordance with which the brightness at a constant intensity of the incident radiation is determined by the local roughness of the faces and the angle of its inclination to the vertical, as well as on the idea of faceted model image, the number of faces which is determined by the resolution of a digital image. A digital image with a resolution of 2048×1536 pixels is divided into 3145728 edges (segments), the brightness of each of which is perceived by the individual photosensitive element and corresponds to a specific pixel.
The inventive method for the contactless determination of parameters of surface roughness based on computer analysis of digital image using a specialized program, obtained using an optical digital device with a CCD (charge-coupled devices) matrix.
The inventive method for the contactless determination allows you to measure two-dimensional roughness parameters of the surface according to GOST 2789-73: Ra, Rz, Rmax, Rq, Rp, S, Sm, η%, tp.
The inventive method for the contactless determination allows the measurement of three-dimensional roughness parameters: Sa - arithmetic mean deviation of the surface; Sz - height surface roughness at ten points; Smax is the maximum height of the surface; Sp - maximum positive deviation of the surface; Sq is the standard deviation of a surface from a reference plane; Sx and Sy is the average step local protrusions along and normal to the direction of tracks, respectively; Smx and Smy - average pitch of irregularities along and normal to the direction of tracks, respectively; Stp - bearing surface at the level of p.
Conducting digital photography investigated surface or area using an optical digital device allows you to quickly obtain the necessary and sufficient data to determine roughness parameters and operative to detect a defective area.
Conducted the e digital photography when lighting angles 15°, 45°, 75° avoids instability lighting conditions, to minimize the effect of darkening the adjacent projections of the asperities of the surface being examined, which affects the accuracy of determination of roughness parameters.
Holding the digital imagery with resolution not less than 3 megapixels allows you to increase the level of detail of the surface, which affects the measurement accuracy.
The normal location of the lens optical digital device with respect to the sample surface prevents glare on the image, creates the conditions for obtaining the image of the real surface geometry.
Image processing in the computer for subsequent analysis speeds up the estimation of the roughness of the entire surface or area, minimizes noise and measurement error, to reduce the sensitivity to contamination of the surface being examined and vibrations, to use the proposed method as part of the automated surface quality control and adaptive control of technological process.
The digital optical connection device with electronic computing machine via the USB interface allows you to quickly transfer your digital photos and manage digital device that improves quality control and allows the use of the proposed method in automated systems for surface quality control and adaptive control of technological process.
The use of computers allows you to quickly calculate the three-dimensional analogues of roughness parameters that more accurately reflect the properties of the entire surface or selected areas.
It is widely known use of photography, including digital, in its various applications in engineering and technologies, for example: the non-contact evaluation of surface roughness of large parts (Abramov A.D., noses, NV Contactless method of assessing surface roughness of large parts /Coll. Tr. international scientific-technical conference. - Samara: SSTU, 2005. - P.3-7); quality control of metal products in materials science (Yakovlev A.V., Panteleev S.V. Application of methods of digital image processing for quality control of metal / proceedings of the III international scientific-technical conference "Medical-ecological information technology - 2000" / Under. edit Nagonenicolo, Ustinova, Vingada, Sagrista. - Kursk: Publishing house of KSTU. - 2000. - s-170). In these methods as the main criteria for evaluating the roughness parameters a flat surface machined on a planer, accepted statistical characteristics. On the basis of image analysis and previously installed dependencies made the transition from walking option is to tall. It should be noted that for flat surfaces with regular microrelief, this approach is valid and can be extended to other types of processing, but it is not acceptable to the spatial complex surfaces and flat areas treated by paths that are different from raster. Typically, processing is done on milling machines for spot touch original instrumental surface oval face milling cutter with the workpiece. Indeed, presents the results of the study confirm the existence of correlation between the parameters of the surface roughness and its image opto-electronic method, but do not allow to determine these parameters for a surface with an irregular terrain.
The need for adaptive control of technological process of cutting requires the creation and implementation of ways to get a comprehensive view of the surface microrelief consisting in the determination of high and stepper settings for individual cross-section profile on the base length, and the entire surface or area. The system should provide the ability to measure complex surfaces and planes, to be oriented to use in a production environment (vibrations, Nirav amerom and inconsistent lighting, the dirt on the surface) and to provide the specified accuracy and reliability of results.
The inventive method allows to solve the problem. The applied method is based on comparison of statistical characteristics of images of the surfaces of the parts obtained with a digital camera, database, formed by reference, certified samples of roughness. Using algorithms that take into account the level of intensity of reflection, which filters the graphics information and the implementation dependencies, allowing to analyze black-and-white image, makes it possible to use this technique for measuring components without removing them from the machine table, which is especially important when processing spatial complex surfaces with repetitive elements. As a rule, finish milling is continued for a long time, the treatment is accompanied by a tool change and it is very undesirable change based environment, which leads to loss of accuracy and disturbance of the continuity of the instrumental track on the surface.
Measuring information in digital format can be used for further computer analysis of the surface layer in various research purposes.
From the above it follows that the proposed tehnicheskomprodlenii has the advantage compared with the known, namely, the invention allows to achieve high speed define the parameters of the roughness of the entire surface or area; to minimize noise and measurement errors (statistical analysis of three-dimensional measurements more reliable and representative, since it includes a larger number of independent data); to quickly identify defective areas on the surface; to make measurements in the form of a photo exhibition and to determine the roughness parameters, both in the laboratory and in production conditions, i.e. with significant vibrations and partial contamination of the surface; to use automated surface quality control and adaptive control of technological process.
Therefore, the proposed technical solution when used gives a positive technical result consists in the immediacy of control, to increase the measurement accuracy, improve quality control, raising awareness results in the control.
The invention is illustrated by drawings, where figure 1 schematically shows the inventive device to implement the method for the contactless determination of parameters of surface roughness;
figure 2-4 - graphs of dependencies calculated roughness parameters Ra, Rz, Sm samples No. 4, 5, 6 (with Ra=12,5; 6,3; 3.2 mm from therefore, its after end milling of lighting angles α=15°, 45°, 75°;
figure 5-7 - the graphs of dependences of the calculated roughness parameters Rp, S, tp samples No. 4, 5, 6 (with Ra=12,5; 6,3; 3.2 mm, respectively) after face milling angle of illumination α=15°, 45°, 75°;
on Fig-10 - the graphs of dependences of the calculated roughness parameters η50, Rmax, Rq samples No. 4, 5, 6 (with Ra=12,5; 6,3; 3.2 mm, respectively) after face milling angle of illumination α=15°, 45°, 75°;
figure 11 - image of the samples ' surfaces with Ra=12,5; 6,3; 3.2 mm (No. 4, 5, 6, respectively) after face milling and 5 control profiles of the investigated sites, with an angle α=15°;
on Fig images of the surfaces of samples with Ra=12,5; 6,3; 3.2 mm (No. 4, 5, 6, respectively) after face milling and 5 control profiles of the investigated sites, with an angle α=45°;
on Fig images of the surfaces of samples No. 4, 5, 6 (with Ra=12,5; 6,3; 3.2 mm, respectively) after face milling and 5 control profiles of the investigated sites, with an angle α=75°;
on Fig images of the surfaces of samples No. 4, 5, 6 (with Ra=12,5; 6,3; 3.2 mm, respectively) after face milling and fragments of three-dimensional models.
Device to implement the method (figure 1) contains:
digital optical device 1 on the CCD (charge-coupled devices) matrix, in this case, the digital camera 1 Sony DSC-P10 5.0 megapixels, f7.9÷23.7 mm, mounted on the laser focus and macro photography; directional light sources 2, 3, 4, each of which consists of a tripod with a fixed discharge lamp Dulux S 11W; electronic computing machine (ECM), 5 technical specifications: AMD Athlon 2.6Ghz, NVidia GeForce4MX 440, 512 Mb, USB 2.0.
Lens digital camera 1 is normal with respect to the sample surface of the sample 6. The light sources 2, 3 and 4 are at angles of 15°, 45° and 75°, respectively, which allows you to create lighting without glare. With this digital camera 1 is connected to the computer 5 through 7 USB interface.
The analyzed sample surface 6 is photographed with alternate switching of the light sources 2, 3 and 4. Obtained three images are transferred to the computer 5 via the USB interface 7. Processing, analysis and determination of the quality of the surface is carried out using the developed program "Microrelief v.1"installed on the computer, the algorithm which is presented in table 1. The program is based on methods of mathematical statistics, mathematical analysis, preparation, image filtering and developed a new method of estimating geometrical parameters.
Produce digital imagery sample surface or her section through a digital optical device in the form of a digital camera with a resolution which m is at least 3 megapixels at angles of illumination 15°, 45°, 75°, with a normal lens digital optical unit relative to the sample surface with sequential switching of the light sources 2, 3, 4.
1. The obtained digital images is conveyed to the computer where they are processed for further analysis program "Microrelief v.1".
Using "Micro v.1" produce analysis of the processed digital images by calculating the statistical characteristics of each of them. Find the standard deviation between the calculated statistical characteristics. The obtained standard deviation is correlated with the arithmetical mean deviation Ra of the sample roughness, made of the same material as measured item, determine the coefficient of restitution k=Ra/M(Δx), where M(Δx)is the expectation of the deviation of the pixel intensity of the analyzed image; Ra - arithmetical mean deviation of profile details, build electronic model of the surface microrelief by converting the pixels of the picture xiin the three-dimensional coordinates x, y and z, which are used to calculate the altitude and walking roughness parameters of the surface, with coordinates x and y define here the position of a pixel in millimeters, and the z coordinate defines the height of a pixel in micrometers.
2. Algorithm implementation the AI method is presented in table 2. Each image of the surface being examined, photographed under different lighting angles 15°, 45° and 75°, passes the stage of preparation and filtration. Next is the calculation of the statistical characteristics of images obtained expositions, is the standard deviation of the statistical characteristics. Correlation of calculated statistical characteristics database reference statistical characteristics is to find the coefficient of restitution k (table 3). Restoration of the surface microrelief produced by the program according to the algorithm given in table 4. Building profiles and 3D topography of the sample surface is obtained when restoring heights and calculated the scale of the pixel in the mm Parameters of a roughness profile of the sample are calculated by the program and is in full compliance with GOST 2789-73 "surface Roughness. Parameters, specifications and designations. Calculation of three-dimensional roughness parameters is performed for the whole sample surface or area according to the mathematical description of three-dimensional analogues, proposed by the authors of the book "Quality of products: a manual. 2nd ed., updated / VAC, Roy, Vaganov. - M.: MGIU, 2006. - 252 S.".
To the calculations of statistical parameters in the algorithm is reducerea calibration of digital images, which is to compensate the difference of the lighting of the inspected image and the reference image. The algorithm is reduced to the scale of brightness.
Database reference statistical attributes that are generated and accumulated by the program "Microrelief v.1" in information processing samples with different roughness, is designed to correlate parameters of the examined surface from a reference stored in the database. The correlation is performed using the interpolation polynomial functions, cubic splines relative to the statistical characteristic that defines Ra (built function to calculate the parameter Ra; as a function uses interpolation polynomial, the coefficients of which are the statistical characteristics of the standards). For the selected reference parameter is determined by the interpolated value of roughness. To create a database reference signs are photography samples-standards with known roughness at angles of illumination specified earlier in the installation, designed for the implementation of the proposed method. Included in a database of statistical parameters, type of processing and material standard.
In the presented image processing algorithms incorporated a method based on the interference filter sliding window (Methods of computer printing handling the Ki images / Ed. Whasoever. - M.: Fizmatlit, 2001. - 784). This method allows you to adhere to high precision in the case of uneven lighting, pollution, glare or shades of the investigated area.
Using the computer allows you to quickly calculate three-dimensional analogues of roughness parameters that more accurately, reliably and clearly reflect the properties of the entire surface or selected areas.
The claimed invention was tested on a test specimen device for contactless determination of parameters of surface roughness on the sample face milling Ra=12,5; 6,3; 3.2 mm.
The results of the tests are presented in tables 5, 6, 7, 8 and figures 2, 3, 4, 5, 6, 7, 8.
From the results shown in figure 2, 3, 4, it follows that the stability parameter Sm has a greater influence lighting angles 15° and 75°, on the stability of tp - lighting angles 15° and 45°. on the stability of η, S - illumination at angles of 45° and 75°, the stability Rmax, Rq, Rp - lighting angle of 15°, and practically does not influence Ra and Rz.
From the results shown in table 5, it follows that the largest difference 12,79%registered at the sample roughness No. 5 parameter Rmax, does not extend beyond the systematic errors of the profilometer-type profilograph A1 model 252.
Conclusion: the claimed invention allows operation and reliably determine the roughness parameters of the entire surface or area within 20 seconds, including digital photography and computer calculation.
|Comparison of results of measurements of samples with Ra=is 12.5; 6,3; 3.2 µm (No. 4, 5, 6, respectively) after face milling by the claimed method for the contactless determination of parameters of surface roughness and contact (traditional)|
|Room roughness sample||The roughness parameter||Contactless method||Contact method||Divergence|
|4 (base length l=2.5 mm; Ra=12.5 μm)||Ra||12,18||12,58||3,24%|
|5 (base length l=2.5 mm; Ra=6.3 μm)||Ra||6,28||to 6.57||4,58%|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||Ra||3,33||3,18||4,40%|
|The results of the test device and method for the contactless determination of parameters of surface roughness on samples with Ra=12,5; 6,3; 3.2 mm (No. 4, 5, 6, respectively) after face milling on a 5-control profiles at angles of α lighting=15°, 45°, 75°|
|Lighting angle, degrees||Room roughness sample||Stat. characteristics sample||The calculated roughness parameters of the investigated area on a 5-control profiles (lines)|
|4 (base length is l=2.5 mm; Ra=12.5 μm)||1||2||3||4||5||average value.|
|15||5 (base length l=2.5 mm; Ra=6.3 μm)||M||130,13||Ra||4,34||6,72||the 7.43||7,22||to 7.67||of 6.68|
|γ3||0,42||Rq||to 5.21||5,96||of 5.81||of 5.92||6,26||of 5.83|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||M||125,25||Ra||3,35||3,79||3,78||3,96||3,48||to 3.67|
|D||1065,63||Rz||12,42||13,13||at 13.84||13,79||13,30||to 13.29|
|σ||32,64||Rmax||15,08||accounted for 14.45||16,09||15,71||16,85||15,64|
|γ3||0,31||Rq||1,99||2,18||of 2.26||to 2.29||2,19||2,18|
|Continuation of table 6.|
|Lighting angle, degrees||Room roughness sample||Stat. characteristics sample||The calculated roughness parameters of the investigated area on a 5-control profiles (lines)|
|4 (base length l=2.5 mm; Ra=12.5 μm)||1||2||3||4||5||average value.|
|γ3||0,14||Rq||9,58||14,07||charged 8.52||to 7.32||7,50||9,40|
|45||5 (base length l=2.5 mm; Ra=6.3 μm)||M||136,09||Ra||6,45||7,97||6,55||6,46||4,00||6,28|
|D||679,7||Rz||32,49||by 40.73||31,10||of 28.26||15,17||29,55|
|γ3||0,44||Rq||6,35||7,44||the ceiling of 5.60||is 4.93||2,63||5,39|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||M||123,11||Ra||3,30||3,14||of 3.64||3,32||3,24||3,33|
|γ4||3,57||Rp||8,78||9,12||at 9.53||of 7.75||8,87||8,81|
|Continuation of table 6.|
|Lighting angle, degrees||Room roughness sample||Stat. characteristics sample||The calculated roughness parameters of the investigated area on a 5-control profiles (lines)|
|4 (base length l=2.5 mm; Ra=12.5 μm)||1||2||3||4||6||average value.|
|75||5 (base length l=2.5 mm; Ra=6.3 μm)||M||127,19||Ra||6,00||6,69||to 4.62||6,01||6,87||6,04|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||M||122,96||Ra||2,70||2,87||3,22||2,20||4,03||3,00|
|D||1732,34||Rz||11,13||to 11.61||14,39||of 9.30||15,54||KZT 12.39|
|γ4||2,81||Rp||9,59||9,26||of 10.21||to 6.57||9,66||9,06|
|The results of measurements of the surface roughness of the contact (traditional) way of samples with Ra=12,5; 6,3; 3.2 mm (No. 4, 5, 6, respectively) after face milling on a 5-control profiles using profilometer-type profilograph A1 model 252|
|Room roughness sample||L mcm||l mcm||The calculated roughness parameters of the investigated area on a 5-control profiles (lines)|
|4 (base length l=2.5 mm; Ra=12.5 μm)||6||2,5||1||2||3||4||5||average value.|
|5 (base length l=2.5 mm; Ra=6.3 μm)||6||2,5||n||15||15||16||14||12|
|Ra||to 6.43||6,05||7,31||5,85||7,22||to 6.57|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||6||0,8||n||22||22||24||21||22|
|L is the length of the route feelings|
|l is a reference length|
|n - the number of projections|
|The results of the test device and method for the contactless determination of roughness parameters of the surface: measurements of three-dimensional roughness parameters and the construction of three-dimensional models of surfaces of samples with Ra=12,5; 6,3; 3.2 mm (No. 4, 5, 6, respectively) after face milling|
|Room roughness sample||The calculated three-dimensional roughness parameters of the investigated sample|
|4 (base length l=2.5 mm; Ra=12.5 μm)||Sa||of 12.26|
|5 (base length l=2.5 mm; Ra=6.3 μm)||Sa||6,64|
|6 (basic length l=0.8 mm; Ra=3.2 μm)||Sa||3,45|
1. Method for the contactless determination of parameters of surface roughness, which consists in conducting digital photography investigated surface or her section through a digital optical device with a minimum resolution of 3 megapixels at angles of illumination 15°, 45°, 75° with the normal lens digital optical unit relative to the sample surface, the transmission of digital images in the electronic computer, the image processing for further analysis and determination of two-dimensional and three-dimensional roughness parameters of the surface, while the analysis of the processed images is performed on the basis of the calculation of the statistical characteristics of each digital image, find the standard deviation between the calculated statistical characteristics of the obtained RMS deviation correlate with the arithmetical mean deviation Ra of the sample roughness, is made of a material as measured item, determine the coefficient of restitution k, build e-model is of the surface microrelief by converting the pixels of the picture x
iin the three-dimensional coordinates x, y and z, which are used to calculate the altitude and walking roughness parameters of the surface, with coordinates x and y define here the position of a pixel in millimeters, and the z coordinate defines the height of a pixel in micrometers, and the recovery factor k is determined by the formula:
where Ra - arithmetical mean deviation of profile details;
M(Δx) is the expectation of the deviation of the pixel intensity of the analyzed image.
2. Device for contactless determination of parameters of surface roughness, characterized in that it contains a digital optical device CCD (charge coupled devices) matrix, at least three directional light source and the electronic computer, and the lens optical digital device is located properly with respect to the sample surface, and directional light sources mounted on tripods at angles of 15°, 45°, 75°, creating lighting without glare, the digital device connected to the electronic computing machine via a universal serial bus Universal Serial Bus (USB), providing the transmission of digital images in the electronic computer.
FIELD: physics, measurements.
SUBSTANCE: invention is related to the field of metering equipment, namely to measurement of moving surface parametres. Charge of explosive substance is initiated with the help of lens or detonation distributor on surface, which is speeded up by explosion products to velocity that causes glow of shock wave in front of it. Receiver of the same shape closed by screen is installed on motion route. Two or more groups of electro-optical detectors are installed in receiver along normal line to moving surface on different bases from initial position of surface. Surface of screen inverted to electro-optical detectors in process of motion interacts with their ends, besides, at the same time electric and light signals are generated, which are supplied to recorders. Recorders measure time of moving surface approach to the end of every detector. Diversity is defined by difference of times of electric and light signals in every group of detectors.
EFFECT: makes it possible to improve reliability and accuracy of measurements of time intervals in complex expensive experiments.
FIELD: measurement of planeness of strip in reel shaft of hot strip rolling mill.
SUBSTANCE: proposed method includes measurement of planeness in reel shaft of hot rolling mill; reel shaft is provided with movable and immovable strips between pulling device and reel; hot strip is fed to reel through its shaft by means of roller table and pulling roller of pulling device; reel is provided with drum, hold-down rollers and end guides; roller for measurement of planeness is closed in reel shaft turned inside guide strip. Moving roller used for measurement of planeness has working position at which hot strip passes around roller used for measurement of planeness retaining approximately constant wrapping angle α and lowered position; reel shaft is provided with swivel guide strip closing the roller used for measurement of planeness.
EFFECT: enhanced economical efficiency; enhanced protection of roller in lowered position.
15 cl, 9 dwg
SUBSTANCE: invention relates to flatness measurement technique and deviation determination at flat surfaces with different square area and length, in particular for testing, installation and marking-off plates made of cast iron or stone. Invention can be used in different areas of engineering. Effect is reached due to emission of horizontal collimated laser beam by measurement instrument with stationary installed emitting device; receiver contains optical target sign with cross and vernier installed at vertical measurement scale with feature of motion in vertical plane. In the beginning real horizontal auxiliary plane is created by laser beam turning; level of this plane is fixed against readings of linear scale and vernier received at receiver adjustment against optical axis of emitter by means of alignment of optical target cross with central point of collimated laser beam. Readings of linear scale and vernier received during such alignment are accepted as zero mark for further setting and measurement. Then moving receiver without realignment to at least two outermost points located at work surface of plate and aligning cross of receiver's optical target sign with central point of emitter's collimated laser beam by means of vertical regulation of plate level in each of these points work surface of plate is set in parallel to horizon and to auxiliary plane and measurements of flatness deviation are made in received system of two mutually aligned real parallel surfaces by means of plate sections movement into leveling points of receiver only and determination of vertical deviation for cross of target sign to one or another side from auxiliary surface level against linear scale and vernier of receiver.
EFFECT: setting of real horizontal auxiliary plane, accurate setting of basic plane in parallel to auxiliary plane and horizon and obtainment of mutually aligned system to make adjustments and measurements based on these two planes really parallel to each other.
SUBSTANCE: running surface wrap and inhomogeneity detector includes sensor designed as fibre-optic measuring probe with radiating and receiving light guides and electronic module. Fibre-optic measuring probe represents two beams of radiating and receiving light guides by randomised optical scheme covered with the third beam of receiving light guides thus ensuring coaxial optical scheme, with working beam ends lying in one plane. Working beam ends are movable and fixed relative to the controlled surface. Additionally receiving light guides of beams are connected through optoelectronic converters to the adder with output connected to the indicator, while radiating light guides of beam are connected to pulse generator.
EFFECT: higher detection accuracy of various wraps and inhomogeneities of controlled surface.
FIELD: physics; measurement.
SUBSTANCE: invention is related to instrumentation and may be used for contactless control of goods with external thread. Device contains movable carriage equipped with electric drive of travel and linear shift detector, support fixed on movable carriage, optical-mechanical unit equipped with electric drive of rotation around longitudinal axis, detector of turn angle and two optoelectronic heads, every of which is formed from optically conjugated source and receiver of light radiation that are installed on different sides from threaded section of item under control. Besides, device contains personal computer (PC), inlets of which are connected to outlets of light radiation receivers, linear shift detector and rotation angle detector, and outlets - to electric drives of shift and rotation. Optical-mechanical unit is arranged in the form of spindle, shaft of which is installed in bearings on support and is equipped with vertical shift mechanism. Spindle head is arranged in the form of two C-shaped holders of optoelectronic heads installed on faceplate on different sides from longitudinal axis of item under control and is equipped with mechanism for interbeam gap adjustment. At that mechanism for spindle shaft vertical displacement is arranged in the form of jack, and mechanism for adjustment of interbeam gap of spindle head represents adjustment shaft with sections of the right and left thread, which are installed in corresponding threaded openings of optoelectronic head holders. Spindle shaft is rigidly fixed to faceplate, and movable carriage is provided on mechanism for spindle shaft vertical displacement. Besides, holders of optoelectronic heads are equipped with guides, between which faceplate is installed, and optical-mechanical unit is equipped with n pairs of optoelectronic heads, where n is integer number and n>1.
EFFECT: expansion of controlled pipe diameters range and higher accuracy of control results.
3 cl, 8 dwg
SUBSTANCE: present invention pertains to the method of determining parameters of an anisotropic structure on angular dependence of reflected monochromatic radiation. The method is distinguished by that, the chosen structure is in form of trench structures with nanometer and submicrometer dimensions of elements. The wave length of the analysing radiation is more than 10-40 times the typical dimensions of the elements of the structure. The analysing radiation in form of a divergent beam is focused on the analysed area of the sample. The intensity of the radiation reflected simultaneously at different angles is recorded. The intensity reflects the angular dependency of the intensity of reflected radiation in the range of angles of incidents used. From this the geometrical parameters of the structure and/or refractive and absorption indices of the material of the trench structure are determined.
EFFECT: wider range of geometrical parameters measured using optical methods.
3 cl, 2 dwg
FIELD: inspection technology.
SUBSTANCE: device can be used for contact-free inspection of items having internal or external thread. Device has base 1 for placing items to be inspected, inspected item's fixing unit 3 provided with internal thread placed onto base 2, first coordinate table provided with longitudinal shift drive and longitudinal shift detector, first electro-optic head 17 placed onto first coordinate table and made of narrow light beam source (for example, laser with optical system), multiple element photoreceiver (for example, linear photoreceiver) and objective. Objective is mounted for provision of triangular optical connection of multiple element photoreceiver with narrow optical light source through corresponding surface of item 3. Device also has personal computer. Inputs of PC are connected with outputs of multiple element photoreceiver and of longitudinal shift detector. Output of PC is connected with longitudinal shift drive. Fixing unit 11 of item to be controlled, provided with external thread, is made in form of two-coned rest-centralizer disposed onto first coordinate table; one of cones is made for removal. Second U-shaped coordinate table is disposed onto base 1; table is provided with drive and lateral shift detector. Second electro-optic head is mounted onto second coordinate table at both sides from item 11. Unit 3 for fixing item is made in form of removable ring-shaped clamp (sleeve) provided with drive of rotation about longitudinal axis and with angular shift detector. First coordinate table is disposed onto base 1.
EFFECT: higher universality of device; ability of inspection as internal and external thread; simplified design.
2 cl, 5 dwg
FIELD: measuring technique.
SUBSTANCE: traverse gear comprises table, movable bridge, four pickups of linear movements along the X, Y1, Y2, and Z coordinates, and pickup of contacting with the probe mounted for permitting movements along the Z coordinate. Each pickup of the linear movements has measuring grid, recording head with carriage provided with indicating grid, and guiding member. The guiding member for all pickups of linear movements is made of two mutually perpendicular planes that are rigidly interconnected. One of the planes of the guiding member is a plane of the measuring grid with marks, and the second plane of the guiding member is made of a glass substrate. The pickup of contacting is made of a pickup of linear movements. The pickup of linear movements along the Z coordinate and the pickup of contacting have the common measuring grid and guiding member. The recording head of the contacting pickup is secured to the measuring grid of the pickup of linear movements along the Z coordinate. The probe is rigidly connected with the carriage of the contacting pickup. The carriage of the contacting pickup bears on the stop when it is in a bottom position. The stop is made of a ball secured to the area perpendicular to the face of the guiding member of the pickup of linear movements along the Z coordinate. The movable bridge is made of a glass channel.
EFFECT: enhanced precision and reduced weight.
FIELD: the invention refers to measuring technique.
SUBSTANCE: an arrangement for definition of roughness of a surface has a laser, in-series located along the laser radiation a half-transmitting mirror installed under an angle of 450 to the optical axle of the arrangement and a photo receiver electrically connected with a measuring block. The arrangement has a spheroconic system, a diaphragm rigidly fixed on the photo receiver, a unit of displacement of the photo receiver along the axle of the arrangement. At that the optical spheroconic system is located between the half-transmitting mirror and the diaphragm on the optical axle of the arrangement.
EFFECT: increases accuracy and reliability of definition of roughness of a surface.
2 cl, 2 dwg
FIELD: testing equipment.
SUBSTANCE: device has cylindrical case with illumination system disposed inside case. Illumination system has incandescent lamp and toroid lens, scale mesh and viewing system's objective. TV system is also introduced into the device. TV system has CCC-array disposed in focal plane of viewing system's objective and video-control unit. Device also has collimator lens disposed in front of objective of viewing system at axis of objective, which axis coincides with longitudinal axis of case. Semi-transparent mirror is mounted in front of collimator lens at its optical axis at angle of 45 degrees to lens. Device also has two semiconductor microscopic lasers. There are cylindrical lenses in front of microscopic lasers.
EFFECT: widened technical abilities.
FIELD: investigating or analyzing materials by the use of optical means.
SUBSTANCE: device comprises endoscope of side vision with measuring scale that is secured in the central flange provided with circular scale. The flange is set in the bushing at the outlet face of the space for permitting rotation of the flange together with the endoscope whose lens is mounted at the center of the space. The axis of sighting is positioned in the zone of ring weld joint that connects hemispheres of the space. The device is additionally provided with flexible passage for lightening internal surface of the space by flat laser beam under various angles. The passage for laser illumination is composed of semiconducting micro-laser mounted at the axis of gradient lens that is mounted at the outlet face of the light guide coincident with the back focus, second gradient lens mounted at the outlet face of the light guide, cylindrical lens, spherical lens, and flat mirror.
EFFECT: expanded functional capabilities.
FIELD: measuring technique.
SUBSTANCE: device has measuring unit which has prod, platform with through opening where measuring unit is installed. Prod is capable of touching surface to be measured and of moving at plane being perpendicular to measured surface and along direction of measurement. Platform is provided with three supports for installation. As measuring unit the linear shift detector is used, which detector has light source, illuminating two diffraction gratings. One of gratings is measuring, being tightly connected with prod, and the other one is additional grating. Detector also has photoreceivers. Supports are made of materials having low temperature expansion coefficient. Supports provide three-point installation of platform onto surface; they are disposed in vertexes of triangle in such a way that one catheter of triangle is parallel to one side of platform.
EFFECT: improved precision of measurement; reduced limitations in size of surface to be measured; accelerated measuring process; widened working temperature range.
FIELD: laser control technologies.
SUBSTANCE: method includes sweep of light beam to straight line with providing for projection of this beam on surface of rolled strip, video capture of projection area of current beam on portion of controlled surface and point of nearby edge of rolled strip, projection area is separated on given number of ranges and for each range received image is separated on components, forming respectively line of edge points of beam light projection, being portion of measurement area, line of brightest points inside light beam projection range and line of edge points of beam projection, quitting measurement area, to determine their coordinates along rolling strip surface, coordinates of lines of brightest points and edge points within light beam projection are straightened, and value of total coordinate is determined, from which with consideration of coordinates of points of lines of brightest points within light beam projection, by geometric interpretation, total parameter of rolled strip shape SARK(i,j) is determined.
EFFECT: higher trustworthiness and efficiency.