CN111397531B - Single laser displacement sensor railway vehicle wheel and tread profile measuring method - Google Patents
Single laser displacement sensor railway vehicle wheel and tread profile measuring method Download PDFInfo
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- CN111397531B CN111397531B CN202010248529.0A CN202010248529A CN111397531B CN 111397531 B CN111397531 B CN 111397531B CN 202010248529 A CN202010248529 A CN 202010248529A CN 111397531 B CN111397531 B CN 111397531B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M17/00—Testing of vehicles
- G01M17/08—Railway vehicles
- G01M17/10—Suspensions, axles or wheels
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Abstract
The method for measuring the wheel and tread profile of the railway vehicle with the single laser displacement sensor comprises a measuring device, wherein the measuring device comprises a position control system and a data analysis system, the position control system ensures the accurate positioning of the measuring position of the laser sensor, and the data analysis system is used for processing the measuring data output by the laser displacement sensor; separating the laser measuring head stroke signal and the Z axis of the machine tool into independent measuring units, and splicing the measuring units in parallel according to the data interface rule by adopting a distributed measuring modular structure; the measuring method comprises the steps of measuring the wheel profile appearance, measuring the equivalent taper of the wheel tread, and evaluating and managing the vehicle running performance by the wheel appearance; the invention is beneficial to simplifying the structure of the measuring device and improving the accuracy of measuring and positioning and the measuring precision.
Description
Technical Field
The invention belongs to the technical field of on-line detection and measurement of geometric shapes and parameters of wheels of railway vehicles, and particularly relates to a method for measuring the wheel and tread profile of a railway vehicle by using a single laser displacement sensor.
Background
The geometric profile of the wheels and tread profiles of a rail vehicle is an important factor affecting high-speed operation of the rail vehicle. Under the condition of long-term running of the wheel tread of the rail vehicle, the problem of wheel contour deformation caused by abrasion generally exists in the field of rail vehicles, and the problem is difficult to thoroughly solve in the field of railway transportation at present. And the recovery of the geometric profile of the wheel and the tread profile is mainly ensured by a turning process, so that the topography measurement of the wheel and the tread profile plays an important role as an essential link in the wheel geometric shape and parameter online detection and measurement process. The measurement mode used on site at present mainly depends on off-line or portable special equipment, the detection and measurement efficiency is low, and meanwhile, due to the inconvenience of measurement operation, the accuracy of wheel and tread profile geometric profile measurement is difficult to guarantee.
Aiming at the requirements of on-line detection and measurement of the geometric shape and parameters of the wheel of the railway vehicle, the problems of on-line turning and on-machine measurement of the tread appearance of the wheel, the measurement of the profile shapes of the wheel and the tread is realized by combining special equipment such as a wheel set processing machine (a wheel drop processing center, a non-wheel drop processing machine), a wheel set measuring machine (an on-rail measuring machine, a wheel shape measuring center) and the like with less sensor number and simplified measuring structure, and meanwhile, the integrated measurement of the non-circularity of the wheel profile and the equivalent taper of the tread is realized on the wheel set processing machine or the wheel set measuring machine.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a method for measuring the wheel profile and the tread profile of a railway vehicle by using a single laser displacement sensor, which is beneficial to simplifying the structure of a measuring device and improving the accuracy of measurement and positioning and the measurement precision.
In order to achieve the above functions, the technical scheme adopted by the invention is as follows:
the method for measuring the wheel and tread profile of the railway vehicle with the single laser displacement sensor comprises a measuring device, wherein the measuring device comprises a position control system and a data analysis system, the position control system ensures the accurate positioning of the measuring position of the laser sensor, and the data analysis system is used for processing the measuring data output by the laser displacement sensor; separating the laser measuring head stroke signal and the Z axis of the machine tool into independent measuring units, and splicing the measuring units in parallel according to the data interface rule by adopting a distributed measuring modular structure;
the measuring method comprises the steps of measuring the wheel profile appearance, measuring the equivalent taper of the wheel tread, and evaluating and managing the vehicle running performance by the wheel appearance.
The measurement of the wheel profile morphology comprises the following steps:
the laser displacement sensor S is parallel to one axial direction of the measuring coordinate system, the laser displacement sensor moves from one end of the Y-direction guide rail to the other end at a constant speed to scan the wheel contour circular arc, the laser displacement sensor is calibrated to move from a point 0 to a point L, and the output signal of the laser sensor is S in the moving processiWherein i is the number of sampling points; meanwhile, the signal output by the Y-direction guide rail linear grating is li，0≤liLess than or equal to L; measuring point coordinate P of wheel contour formed by two signalsi(li，si)；
Using measured point coordinates Pi(li，si) The data is fitted with a wheel profile curve to obtain the absolute value P 'of tangent vector of the fitted curve at each measuring point'iAnd max (P'i) And min (P'i)；max(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as max(s)i)，min(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as min(s)i) The difference b between the two is expressed as:
bi＝max(si)-min(si)
the wheel radius R is calculated by the formula:
rotation of the wheel by a set angle to obtain a function R related to the radial movement of the wheeljThe expression is as follows:
Rj＝Rj(θj)
output signal s of laser displacement sensorjThe wheel runout signal is:
and then, carrying out noise elimination and smooth filtering processing on the data output by the laser displacement sensor, and finally transmitting the data output by the laser displacement sensor to a data analysis system.
The measurement of the equivalent taper of the wheel tread comprises the following steps:
the laser displacement sensor starts to measure the tread profile of the wheel along the Z-direction guide rail from the wheel rim reference surface, the measurement of the tread profile and the wheel rim appearance is completed, the width of the tread profile and the wheel rim profile is H, and the output signal of the laser displacement sensor in the moving process is HiWherein i is the number of sampling points; meanwhile, the signal output by the Z-direction guide rail linear grating is ei，0≤eiH is less than or equal to H; measuring point coordinate Q of tread and rim contour formed by two signalsi(ei，hi)；
Taking the tread contact line as the origin of coordinates of the section, carrying out error separation and pretreatment on the measured data, calculating a QR value from the processed data, calculating equivalent taper of the tread according to Kingel,
in the formula, lambda is the wavelength of the motion trail of the wheel set; e is the distance between the contact spots of the left wheel track and the right wheel track, namely the span; r0The rolling circle radius of the wheel when the wheel set is in the centering position; gamma rayeThe angle of the taper of the wheel tread is; tan gammaeThe equivalent taper of the wheel tread.
The evaluation and management of the wheel morphology to the vehicle running performance comprises the following steps: by measuring data QiComparing the measured profile with the standard tread profile to obtain the deviation of the measured profile and the standard profile and obtain the abrasion loss of the wheel rim; meanwhile, the signals output by the laser displacement sensor can also be used for tread modification and judgment of the abrasion degree of the tread.
The dispersion measurement module comprises a laser displacement sensor which is fixed on a measurement base with an orthogonal structure, so that the measurement base has a fixed Y-Z coordinate system or an X-Z coordinate system, and if the measurement space structure is restricted, the Z coordinate system is replaced by a Z axis or a single motion axis of a machine tool or a measuring machine.
The invention has the beneficial effects that:
1. the measuring device used by the measuring method has the advantages of simple and reliable structure, small number of sensors, high measuring precision and the like, can be used for on-line measurement and maintenance of the wheel morphology of the rail vehicle, and can also be used for performance evaluation of the wheel morphology of the vehicle; compared with other measuring methods, the method can be directly applied to on-machine and on-line measurement of machine tools, wheel shape measuring machines and the like, and can provide adaptability of on-machine application.
2. The measuring method can simplify the measuring complexity and is easier to be applied to various engineering practices.
Drawings
FIG. 1 is a schematic diagram of a dispersion measurement module of the present invention.
Fig. 2 is a schematic diagram of the present invention for measuring a radial profile parameter of a wheel.
FIG. 3 is a schematic view of the present invention measuring the parameters of the wheel axial tread profile.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings. The method is described by specifically combining a wheel-set turning machine tool, and the method for measuring the wheel profile and the tread profile of the railway vehicle with the single laser displacement sensor reduces the structural difficulty of the measuring device on the machine tool and the measuring machine and can ensure that a more accurate measuring result is obtained.
The method for measuring the wheel and tread profile of the railway vehicle with the single laser displacement sensor comprises a measuring device, wherein the measuring device comprises a position control system and a data analysis system, the position control system ensures the accurate positioning of the measuring position of the laser sensor, and the data analysis system is used for processing the measuring data output by the laser displacement sensor; the influence of the self vibration of the machine tool or the measuring machine on the position measuring signal in the online measuring process is considered, the laser measuring head stroke signal and the Z axis of the machine tool are separated into independent measuring units, the online measuring precision of the measuring device is improved, the measuring device adopts a distributed measuring modular structure and is spliced in parallel according to the data interface rule, the complexity of multi-unit measurement is reduced, the expansion is facilitated, the two units of data analysis and the measuring device are enabled to be independent, the transmission of measuring data and the upper-layer analysis of the data are facilitated, and the real-time performance of online measurement and the expansibility of the data analysis are improved.
Referring to fig. 1, in the distributed measurement module of this embodiment, a laser displacement sensor is fixed on a measurement base having an orthogonal structure, so that the measurement base has a fixed Y-Z coordinate system or X-Z coordinate system, if the Z coordinate system is replaced by a Z axis or a single motion axis of a machine tool or a measuring machine due to the restriction of a measurement space structure, it should be ensured that the resolution measurement of the selected laser displacement sensor is much smaller than the measurement accuracy specified by the UIC-519 standard, and meanwhile, the deviation between the installation position of the laser displacement sensor and each motion axis is smaller than the measurement accuracy specified by the UIC-519 standard, so that the central measurement position of the laser displacement sensor is basically coincident with the axis motion central position; according to practical application, the resolution of the laser displacement sensor is 5 μm, the frequency response is 500Hz, the linearity is less than 0.05%, and the highest sampling frequency of data acquisition is 2 kHz.
The method for measuring the wheel and tread profile of the railway vehicle by using the single laser displacement sensor comprises the following steps:
1) mounting a laser displacement sensor on a measuring base, and calibrating the position of the laser displacement sensor;
2) carrying out position calibration on the laser displacement sensor, and determining a position coefficient of the laser displacement sensor;
3) adjusting the measuring position, and keeping the verticality and parallelism of the measuring position and the measuring coordinate in a good state;
4) connecting a control system and a data analysis system;
5) the control system drives the measuring base to move, and the laser displacement sensor returns to the zero position of the coordinate;
6) the laser displacement sensor moves from Y to one end of the guide rail to the other end at a constant speed to scan the wheel contour circular arc, and is calibrated to move from a point 0 to a point L, wherein L/2 is positioned at the middle point of the measured circular arc, and the laser displacement sensor measures the radial contour parameters of the wheel as shown in figure 2; the output signal of the laser displacement sensor in the moving process is siWherein i is the number of sampling points; meanwhile, the signal output by the Y-direction guide rail linear grating is li，0≤liLess than or equal to L; measuring point coordinate P of wheel contour formed by two signalsi(li，si) Then calculating wheel parameters and storing the measured data;
using measured point coordinates Pi(li，si) The data is fitted with a wheel profile curve to obtain the absolute value P 'of tangent vector of the fitted curve at each measuring point'iAnd max (P'i) And min (P'i)；max(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as max(s)i)，min(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as min(s)i) The difference b between the two is expressed as:
bi＝max(si)-min(si)
the wheel radius R is calculated by the formula:
rotation of the wheel by a set angle to obtain a function R related to the radial movement of the wheeljThe expression is as follows:
Rj＝Rj(θj)
output signal s of laser displacement sensorjThe wheel runout signal is:
7) the laser displacement sensor moves to the radial lowest position of the wheel, the tread profile of the wheel is measured along the Z-direction guide rail, the measurement of the tread profile and the wheel rim appearance is completed, the width of the tread and the wheel rim profile is H, the laser displacement sensor measures the wheel axial tread profile parameter, as shown in figure 3, the output signal of the laser sensor in the moving process is HiWherein i is the number of sampling points; meanwhile, the signal output by the Z-direction guide rail linear grating is ei，0≤eiH is less than or equal to H; measuring point coordinate Q of tread and rim contour formed by two signalsi(ei，hi) (ii) a Then calculating the outline of the tread and storing the measured data;
taking the tread contact line as the origin of coordinates of the section, carrying out error separation and pretreatment on the measured data, calculating a QR value from the processed data, calculating equivalent taper of the tread according to Kingel,
in the formula, lambda is the wavelength of the motion trail of the wheel set; e is the distance between the contact spots of the left wheel track and the right wheel track, namely the span; r0The rolling circle radius of the wheel when the wheel set is in the centering position; gamma rayeThe angle of the taper of the wheel tread is; tan gammaeThe equivalent taper of the wheel tread;
by measuring data QiComparing the measured profile with the standard tread profile to obtain the deviation of the measured profile and the standard profile and obtain the abrasion loss of the wheel rim; meanwhile, the signal output by the laser displacement sensor can also be used for tread modification and judgment of the abrasion degree of the tread;
8) after the measurement in the two directions is finished, the control system controls the laser displacement sensor to return to a zero position;
9) and analyzing and processing the acquired measurement signals, storing the signals of the axial position and the radial position of the wheel, and outputting measurement and analysis results.
Claims (1)
1. A single laser displacement sensor rail vehicle wheel and tread contour measuring method is characterized in that: the device comprises a measuring device, wherein the measuring device comprises a position control system and a data analysis system, the position control system ensures the accurate positioning of the measuring position of the laser displacement sensor, and the data analysis system is used for processing the measuring data output by the laser displacement sensor; separating a laser displacement sensor stroke signal and a machine tool Z axis into independent measuring units, and splicing the measuring units in parallel by adopting a dispersion measuring module according to a data interface rule;
the measuring method comprises the steps of measuring the wheel profile appearance, measuring the equivalent taper of the wheel tread, and evaluating and managing the vehicle running performance by the wheel appearance;
the measurement of the wheel profile morphology comprises the following steps:
the laser displacement sensor S is parallel to one axial direction of the measuring coordinate system, and the laser displacement sensor moves from one end of the Y-direction guide rail to the other end at a constant speed to scan the wheel contour circular arc and is calibrated from a point 0Moving to the L point, wherein the output signal of the laser displacement sensor is s in the moving processiWherein i is the number of sampling points; meanwhile, the signal output by the Y-direction guide rail linear grating is li，0≤liLess than or equal to L; measuring point coordinate P of wheel contour formed by two signalsi(li，si)；
Using measured point coordinates Pi(li，si) The data is fitted with a wheel profile curve to obtain the absolute value P 'of tangent vector of the fitted curve at each measuring point'iAnd max (P'i) And min (P'i)；max(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as max(s)i)，min(P’i) The output value of the laser displacement sensor corresponding to the measuring point is marked as min(s)i) The difference b between the two is expressed as:
bi＝max(si)-min(si)
the wheel radius R is calculated by the formula:
rotation of the wheel by a set angle to obtain a function R related to the radial movement of the wheeljThe expression is as follows:
Rj＝Rj(θj)
output signal s of laser displacement sensorjThe wheel runout signal is:
then, denoising and smoothing filtering processing are carried out on the data output by the laser displacement sensor, and finally the data output by the laser displacement sensor is transmitted to a data analysis system;
the measurement of the equivalent taper of the wheel tread comprises the following steps:
the laser displacement sensor starts to be arranged along from the wheel rim reference surfaceMeasuring the tread profile of the wheel along the Z-direction guide rail to finish the measurement of the tread profile and the wheel rim profile, wherein the width of the tread profile and the wheel rim profile is H, and the output signal of the laser displacement sensor in the moving process is HiWherein i is the number of sampling points; meanwhile, the signal output by the Z-direction guide rail linear grating is ei，0≤eiH is less than or equal to H; measuring point coordinate Q of tread and rim contour formed by two signalsi(ei，hi)；
Taking the tread contact line as the origin of coordinates of the section, carrying out error separation and pretreatment on the measured data, calculating a QR value from the processed data, calculating equivalent taper of the tread according to Kingel,
in the formula, lambda is the wavelength of the motion trail of the wheel set; e is the distance between the contact spots of the left wheel track and the right wheel track, namely the span; r0The rolling circle radius of the wheel when the wheel set is in the centering position; gamma rayeThe angle of the taper of the wheel tread is; tan gammaeThe equivalent taper of the wheel tread;
by measuring data QiComparing the measured profile with the standard tread profile to obtain the deviation of the measured profile and the standard profile and obtain the abrasion loss of the wheel rim; meanwhile, the signal output by the laser displacement sensor can also be used for tread modification and judgment of the abrasion degree of the tread;
the dispersion measurement module comprises a laser displacement sensor which is fixed on a measurement base with an orthogonal structure, so that the measurement base has a fixed Y-Z coordinate system or an X-Z coordinate system, and if the measurement space structure is restricted, the Z coordinate system is replaced by a Z axis or a single motion axis of a machine tool or a measuring machine.
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| CN112817317A (en) * | 2021-01-04 | 2021-05-18 | 湖南长院悦诚装备有限公司 | Automatic tracking method and system of intelligent track laying vehicle |
| CN114112448B (en) * | 2021-11-24 | 2024-02-09 | 中车长春轨道客车股份有限公司 | F-rail-based test device and test method for dynamic limit of magnetic levitation vehicle |
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| CN102607426A (en) * | 2012-03-26 | 2012-07-25 | 西南交通大学 | Wheel profile laser measurement device |
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|---|---|---|---|---|
| JPH08122043A (en) * | 1994-10-26 | 1996-05-17 | Banzai:Kk | Measuring apparatus for tire-tread residual amount |
| CN2557381Y (en) * | 2002-07-31 | 2003-06-25 | 广州市奥特控制工程有限公司 | Dynamic detector for train wheel pair size |
| CN2715134Y (en) * | 2004-07-27 | 2005-08-03 | 北京航天计量测试技术研究所 | Wheel pair automatic measuring device |
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