Platform gauge measurement error evaluation method

Abstract

The invention discloses a platform gauge measurement error evaluation method, which comprises the following steps of: measuring parameter values of each gauge size of a platform by using a measurement trolley; substituting the parameter values obtained in the step 1 into a corresponding limit size formula, and calculating the numerical value of the corresponding limit size; moving the measuring trolley, carrying out repeated measurement for multiple times at a given advancing unit step length, and recording data; the method comprises the following steps: establishing a measurement model, calculating uncertainty of each component of the measurement model, calculating total synthesis standard uncertainty uci, calculating expansion uncertainty U, comparing the value of the calculated U with the half-width value of the maximum allowable error interval of the corresponding limit size, and if the value of the calculated U is smaller than the half-width value, determining that the limit size is smaller than the maximum allowable error interval of the limit size, and if the value of the calculated U is smaller than the half-width value, determining that the limit size is smaller than the maximum allowable error interval of the limit size. And if so, the measured gauge size parameter can be judged to be qualified. The method of the steps can evaluate the measurement of the related parameters of the measurement gauge size of the platform, thereby ensuring the accuracy and reliability of the measurement.

Description

Technical Field

[0001] The invention relates to the technical field of station platform clearance measurement, and in particular to a platform clearance measurement error assessment method. Background Art

[0002] In the process of railway transportation, the platform limit mainly refers to the fixed distance between the rail and the platform. There is a certain distance between the edge of the station platform and the center line of the station track to prevent the train from contacting the platform when running on a straight line or curve, so as to ensure the safe passage of the train. In order to ensure the safety of trains when entering the station, the limit detection is carried out at least once a quarter. When there is a change that affects the limit (such as construction, platform deformation and settlement, etc.), it should be measured at any time, and violations should be found and handled in time to ensure the safety of trains.

[0003] At present, railway building construction departments mostly use handheld tools to measure various parameters of platform limits, but the measurement efficiency is low, and fixed-point measurements can only be performed on individual sections, and measurement errors are easily caused by human factors. The existing technology also uses a measuring trolley to perform static measurements on various parameters of platform limits, but due to factors such as changes in ambient temperature, the sensor readings are also prone to errors. How to judge whether the relevant parameters of platform limit size are measured accurately, the existing technology lacks corresponding methods for evaluation. Summary of the invention

[0004] In view of the above shortcomings, the present invention proposes a platform clearance measurement error evaluation method, which can evaluate the relevant parameters of the platform measurement clearance size, thereby ensuring the accuracy and reliability of the measurement.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme:

[0006] A platform clearance measurement error evaluation method, comprising:

[0007] Step 1: Use the measuring trolley to measure the parameter values ​​of the platform's limit dimensions;

[0008] Step 2: Substitute the parameter value obtained in step 1 into the corresponding limit dimension formula, and calculate the value of the corresponding limit dimension;

[0009] Step 3: Move the measuring vehicle, perform repeated measurements at a given unit step length, and record the data;

[0010] Step 4: Establish a measurement model, calculate the uncertainty of each component of the measurement model, and calculate the total combined standard uncertainty u ci , and calculate the expanded uncertainty U,

[0011] U=u ci×k, where k is the inclusion factor and i is the size number;

[0012] Step 5: Compare the value of U calculated in step 4 with the half-width value of the maximum allowable error interval of the corresponding limit dimension. If the calculated value of U is smaller than the half-width value, it can be determined that the measured limit dimension parameters are qualified.

[0013] The platform limit measurement error assessment method according to the embodiment of the present invention has at least the following beneficial effects: by measuring the parameter value of each limit dimension, then by establishing a measurement model of the corresponding limit dimension, and calculating the components of the uncertainty of each limit dimension, the expanded uncertainty of the corresponding limit dimension is finally calculated, and by comparing the expanded uncertainty with the half-width value of the maximum allowable error interval of the limit dimension, it is helpful to evaluate whether the corresponding measurement value is qualified, thereby ensuring the accuracy and reliability of the limit dimension measurement, and facilitating the formation of a standardized assessment process for the limit dimension measurement of the platform.

[0014] Furthermore, the measuring trolley comprises running wheels and a crossbeam, the running wheels are used to roll in contact with the track, two ends of the crossbeam are provided with displacement sensors and measuring wheels respectively, the measuring wheels are in contact with the inner wall of the track, and the displacement sensors are used to obtain the distance l1 between the end point of the crossbeam and the contact point;

[0015] The limit size formula in step 2 is used to calculate the track gauge L1.

[0016] L1=l3+2×l1, where l3 is the length of the beam;

[0017] u in step 3 ci Including the combined standard uncertainty u of the calculated track gauge c1 ,

[0018]

[0019] Among them, c1 to c7 are sensitivity coefficients, u 11 The uncertainty introduced by the repeatability or measurement resolution of the track gauge measurement, u 12 is the uncertainty introduced by the measurement indication error of the displacement sensor, u 13 The uncertainty introduced by the effective height deviation between the contact point and the lowest generatrix of the running wheel, u 14 is the uncertainty introduced by the flatness of the running wheel, u 15 The uncertainty introduced by the wear of the measuring wheel, u 16 The uncertainty introduced by the runout of the working surface of the measuring wheel to its own axis, u 17 The uncertainty is introduced by the difference in expansion coefficient between the rail sleepers of the track and the measuring structure of the measuring trolley.

[0020] Furthermore, the uncertainty u introduced by the repeatability of the track gauge measurement is calculated based on the type A analysis. a , Calculate the uncertainty u introduced by the track gauge measurement resolution based on Class B analysis b , then u 11 =max[u a ,u b ];

[0021] Calculate u a The steps include: measuring n sets of experimental data and recording the data values ​​L i , and calculate the mean value of the data The experimental standard deviation s is calculated by the Bessel formula. i (L),u a =s i (L), as follows:

[0022]

[0023] Calculate u b The steps include: Where a is the half-width of the allowable error of the measurement calculation accuracy, and k is the coverage factor.

[0024] Furthermore, based on the Class B analysis, u 12 to u 17 , as follows:

[0025] Among them, i is the serial number of each uncertainty, a i is the half-width value of the allowable error of the corresponding serial number measurement calculation accuracy, and k is the coverage factor.

[0026] Furthermore, the measuring trolley further comprises a vertical rod, on which two laser distance measuring modules are arranged at intervals, the laser distance measuring modules and the measuring wheel are located in the same vertical plane, and the laser distance measuring modules are used to measure the distance l4 from the laser starting point to the platform;

[0027] The limit dimension formula in step 2 also includes calculating the limit lateral dimension L2,

[0028] Wherein, l5 is the distance between the laser starting point and the contact point between the measuring wheel and the track;

[0029] u in step 3 ci It also includes the combined standard uncertainty u of the calculated limit transverse dimension c3 ,

[0030]

[0031] Among them, c1 to c5 are sensitivity coefficients, u 31 The uncertainty introduced by the repeatability or measurement resolution of the limit lateral dimension measurement, u 32 is the uncertainty introduced by the measurement indication error of the laser ranging module, u 33 is the uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 34 The uncertainty introduced by the track gauge measurement, u 35 Uncertainty introduced for the verticality of the vertical rod.

[0032] Furthermore, the measuring vehicle further comprises an inclination sensor, and the inclination sensor is used to obtain an angle α between the top surface of the actual track and the horizontal plane;

[0033] The limit dimension formula of step 2 includes the theoretical calculated value H of the track superelevation,

[0034] H = 1505 × sin (α);

[0035] u in step 3 ci Including the extremely high combined standard uncertainty u of the calculated orbit c2 ,

[0036]

[0037] Among them, c1 to c4 are sensitivity coefficients, u 21 The maximum value of uncertainty introduced by ultra-high measurement repeatability and measurement resolution, u 22 is the uncertainty introduced by the measurement indication error of the inclination sensor, u 23 is the uncertainty introduced by the flatness of the running wheel, u 24 The standard uncertainty introduced by the difference in expansion coefficient between the rail sleeper of the track and the superelevation measurement structure of the measuring trolley rail.

[0038] Furthermore, the measuring trolley further comprises a vertical rod, on which two laser distance measuring modules are movably arranged at intervals, the laser distance measuring modules and the measuring wheel are located on the same vertical plane, and the laser distance measuring modules are used to measure the distance l4 from the laser starting point to the platform. In the step 1, the laser module measures the distance to the edge of the platform once per unit moving step, records relevant data, and determines whether the laser just hits the top surface of the platform based on the data;

[0039] The limit dimension formula in step 2 also includes calculating the limit vertical dimension L3,

[0040] L3=l6+l7, wherein l6 is the travel distance of the laser module, and l7 is the vertical height of the laser to the track surface.

[0041] Furthermore, if the track surface is level or the inner rail is superelevated, when the reading of the laser ranging module is 0 mm or greater than 2000 mm, it is determined that the laser just hits the top surface of the platform;

[0042] If the outer rail of the track is superelevated, a calculation value T is introduced to determine whether the laser point just hits the top surface of the platform. When the value of T is greater than the threshold value 10, it is determined that the laser just hits the top surface of the platform, as shown in the following formula:

[0043] Wherein, β2 is the current reading of the laser ranging module, β1 is the last reading of the laser ranging module, and α is the unit moving step of the laser ranging module.

[0044] Furthermore, the laser ranging module is connected to a slide module for driving it to move in a vertical direction, and the slide module includes a driving motor;

[0045] u in step 3 ci It also includes the calculation of the uncertainty of the vertical dimension u c4 ,

[0046]

[0047] Among them, c1 to c5 are sensitivity coefficients, u 41 The uncertainty introduced by the repeatability and / or measurement resolution of the vertical dimension measurement of the platform clearance, u 42 is the uncertainty introduced by the indication error of the drive motor, u 43 is the uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 44 is the uncertainty introduced by the verticality of the vertical rod, u 44 The uncertainty introduced by the difference in expansion coefficient between the platform and the vertical rod.

[0048] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0050] Figure 1 It is a structural schematic diagram of a platform without superelevation phenomenon in a platform limit measurement error assessment method of the present invention;

[0051] Figure 2 for Figure 1Schematic diagram of the structure with superelevation on the middle platform.

[0052] In the figure: platform 100, track 200. DETAILED DESCRIPTION

[0053] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "inside", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0055] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If the terms "first" or "second" are described, they are only used for descriptive purposes and cannot be understood to indicate or imply relative importance.

[0056] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] See also Figure 1 and Figure 2 , a platform clearance measurement error evaluation method, comprising:

[0058] Step 1: Use a measuring vehicle to measure the parameter values ​​of each limit dimension of the platform 100;

[0059] Step 2: Substitute the parameter values ​​obtained in step 1 into the corresponding limit dimension formula and calculate the value of the corresponding limit dimension;

[0060] Step 3: Move the measuring vehicle, perform repeated measurements at a given unit step length, and record the data;

[0061] Step 4: Establish a measurement model, calculate the uncertainty of each component of the measurement model, and calculate the total combined standard uncertainty u ci , and calculate the expanded uncertainty U,

[0062] U=u ci ×k, where k is the inclusion factor and i is the serial number of each limit dimension;

[0063] Step 5: Compare the value of U calculated in step 4 with the half-width value of the maximum allowable error interval of the corresponding limit dimension. If the calculated value of U is less than the half-width value, it can be judged that the measured limit dimension parameters are qualified.

[0064] The platform limit measurement error assessment method of the above steps measures the parameter value of each limit dimension, then establishes a measurement model for the corresponding limit dimension, and calculates the components of the uncertainty of each limit dimension, and finally calculates the expanded uncertainty of the corresponding limit dimension. By comparing the expanded uncertainty with the half-width value of the maximum allowable error interval of the limit dimension, it is helpful to evaluate whether the corresponding measurement value is qualified, thereby ensuring the accuracy and reliability of the limit dimension measurement, and is conducive to forming a standardized assessment process for the limit dimension measurement of platform 100.

[0065] Furthermore, the measuring trolley includes running wheels and a crossbeam, the running wheels are used to roll in contact with the track 200, and displacement sensors and measuring wheels are respectively provided at both ends of the crossbeam, the measuring wheels are in contact with the inner wall of the track 200, and the displacement sensor is used to obtain the distance l1 between the end point of the crossbeam and the contact point;

[0066] The limit dimension formula in step 2 calculates the track gauge L1 of track 200,

[0067] L1=l3+2×l1, where l3 is the length of the beam;

[0068] u in step 3 c i includes the combined standard uncertainty u of the calculated track gauge c1 ,

[0069]

[0070] Among them, c1 to c7 are sensitivity coefficients, u 11 The uncertainty introduced by the repeatability or measurement resolution of the track gauge measurement, u 12 The uncertainty introduced by the measurement indication error of the displacement sensor, u 13 The uncertainty introduced by the effective height deviation between the contact point and the lowest generatrix of the running wheel, u 14 The uncertainty introduced by the flatness of the running wheel, u 15The uncertainty introduced by the wear of the measuring wheel, u 16 The uncertainty introduced by measuring the runout of the working surface of the wheel relative to its own axis, u 17 The uncertainty introduced by the difference in expansion coefficient between the sleepers of track 200 and the measuring structure of the measuring trolley.

[0071] Specifically, the structure of the measuring trolley involved in this application can be found in publication number CN 216206049 U, which discloses a platform building clearance laser measuring instrument. Among them, the rolling contact between the running wheels and the track 200 is conducive to improving the smoothness of the movement of the measuring trolley. When establishing a track gauge measurement model, considering u 11 to u 17 The deviations involved in the corresponding situations fully consider the errors caused by the relevant components, and thus better evaluate the correctness and reliability of the numerical value of the track gauge measurement. Among them, the displacement sensor is a prior art and will not be described in detail.

[0072] Furthermore, the uncertainty u introduced by the repeatability of the track gauge measurement is calculated based on the type A analysis. a , Calculate the uncertainty u introduced by the track gauge measurement resolution based on Class B analysis b , then u 11 =max[u a ,u b ];

[0073] Calculate u a The steps include: measuring n sets of experimental data and recording the data values ​​L i , and calculate the mean value of the data The experimental standard deviation s is calculated by the Bessel formula. i (L),u a =s i (L), as follows:

[0074]

[0075] Calculate u b The steps include: Where a is the half-width of the allowable error of the measurement calculation accuracy, and k is the coverage factor.

[0076] Furthermore, based on the Class B analysis, u 12 to u 17 , as follows:

[0077] Among them, i is the serial number of each uncertainty, a i is the half-width value of the allowable error of the corresponding serial number measurement calculation accuracy, and k is the coverage factor.

[0078] Specifically, in the uncertainty analysis of track gauge measurement, the measuring trolley is used to measure the track gauge 10 times under repeatability conditions, and the following table data is obtained:

[0079] n(number of times) 1 2 3 4 5 6 7 8 9 10 <![CDATA[L1(mm)]]> 1435.0 1435.1 1435.0 1435.0 1435.1 1435.0 1435.0 1435.1 1435.1 1435.0

[0080] Calculate u a :Then substitute the data into s i (L), we get the experimental standard deviation of track gauge s1(L) = 0.01 mm, then u a =s1(L)=0.0516mm.

[0081] Calculate u b :Since the measurement resolution of the measuring car is 0.1, then a=0.05mm, assuming uniform distribution, including factor From the corresponding formula we can know: Then u a Greater than u b , so the uncertainty introduced by the resolution is negligible, then u 11 =u a =0.0516mm.

[0082] Calculate u 12 :Since the maximum indication error of the displacement sensor of the measuring trolley is ±0.05mm, then a=0.05mm, and there are 2 displacement sensors, assuming that they obey uniform distribution, including factor From the corresponding formula we can get

[0083] Calculate u 13 :Since the effective height of the gauge measurement point from the lowest busbar of the running wheel is 16mm±0.20mm, and the maximum allowable error is ±0.20mm, then a=0.05mm, assuming uniform distribution, including factor From the corresponding formula we can get

[0084] Calculate u 14 :Since the working busbars of each running wheel should be in the same plane, the flatness should not be greater than 0.2mm, assuming uniform distribution, including factors From the corresponding formula we can get

[0085] Calculate u 15 :Since the diameter change of the measuring wheel within the allowable life mileage should not exceed 0.20mm, and there are two measuring wheels on the measuring cart, it is assumed that it obeys uniform distribution, including factor From the corresponding formula we can get

[0086] Calculate u 16 :Since the runout of the working surface of the measuring wheel to its own rotation axis should not be greater than 0.10mm, and there are two measuring wheels on the measuring cart, it is assumed that it obeys uniform distribution, including factors From the corresponding formula we can get

[0087] Calculate u 17 :The expansion coefficient of the sleeper of track 200 is α2=11.5×10 -6 / ℃, the gauge measuring structure of the measuring trolley is made of 304 stainless steel, and its corresponding expansion coefficient is α1=17.2×10 -6 / ℃, in actual measurement, there is a certain temperature difference between the sleeper and the gauge, and it falls anywhere in the estimated range (-3~3)℃ with equal probability, that is, the half width a is 1435×(17.2-11.5)×10 -6 ×3=0.0245mm, assuming triangular distribution, including factor From the corresponding formula we get

[0088] Calculate u c1 : Among them, c1 to c7 take the value of 1, and the final calculation is u c1 =0.1986mm.

[0089] Calculate the expanded uncertainty of track gauge: U = u ci ×k, where k is 2, and U is calculated to be 0.1986×2=0.3971mm.

[0090] Calculation conclusion: Since the maximum allowable error of the track gauge of the measuring trolley is ±0.5mm, the expanded uncertainty of the track gauge measurement of the limit trolley should not be greater than the half-width value of the maximum allowable error interval, that is, 0.5mm. The track gauge measurement U=0.3971mm of the measuring trolley is less than 0.5mm, which meets the measurement requirements.

[0091] See also Figure 1 and Figure 2 , further, the measuring trolley also includes a vertical rod, on which two laser distance measuring modules are arranged at intervals, the laser distance measuring modules and the measuring wheel are located in the same vertical plane, and the laser distance measuring modules are used to measure the distance l4 from the laser starting point to the platform 100;

[0092] The limit dimension formula in step 2 also includes the calculation of the limit lateral dimension L2,

[0093] Where l5 is the distance between the laser starting point and the contact point between the measuring wheel and the track 200;

[0094] u in step 3 ci also includes the combined standard uncertainty u of the calculated limit lateral dimension c3 ,

[0095]

[0096] Among them, c1 to c5 are sensitivity coefficients, u 31 The uncertainty introduced by the repeatability and / or measurement resolution of the limit transverse dimension measurement, u 32 The uncertainty introduced by the measurement indication error of the laser ranging module, u 33 The uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 34 The uncertainty introduced by the track gauge measurement, u 35 Uncertainty introduced for the verticality of the vertical rod.

[0097] Specifically, the measurement model of the bounded lateral dimension considers u 31 to u 35 The deviations involved in the corresponding situations fully consider the errors caused by the relevant components, and thus better evaluate the correctness of the measured values ​​of the limit lateral dimensions. Among them, the laser ranging module is a prior art and will not be described in detail.

[0098] When conducting uncertainty analysis on limit lateral dimension measurement, the specific calculation process is analogous to the calculation and analysis steps of track gauge. First, the track gauge is measured 10 times under repeatable conditions using a measuring trolley, and the following table data is obtained.

[0099] n(number of times) 1 2 3 4 5 6 7 8 9 10 <![CDATA[L2(mm)]]> 1800.0 1800.1 1800.0 1800.0 1800.0 1800.1 1800.0 1800.1 1800.1 1800.0

[0100] Uncertainty u introduced by repeatability of measurement of lateral dimension of calculation limit a1 :Then substitute the data into s i (L), the experimental standard deviation of the limit lateral dimension is s2(L) = 0.0882 mm, then u a1 =s2(L)=0.0882mm.

[0101] Uncertainty u introduced by the measurement resolution of the lateral dimension of the calculated limit b1 :Since the measurement resolution of the measuring car is 0.1, then a=0.05mm, assuming uniform distribution, including factor From the corresponding formula we can know: Because u a1 Greater than u b1 , so the uncertainty introduced by the resolution is negligible, then u 31 =u a1 =0.0882mm.

[0102] Calculate u 32:Since the maximum indication error of the laser ranging module is ±1mm, it is assumed to obey uniform distribution, including factor From the corresponding formula we can get

[0103] Calculate u 33 :Since the verticality between the laser module and the vertical rod is no more than 0.05mm, it is assumed to obey uniform distribution, including factor From the corresponding formula we can get

[0104] Calculate u 34 :Since the expanded uncertainty of track gauge measurement is U = 0.3971 mm, the uncertainty introduced by track gauge measurement is u 34 =0.3971 / 2=0.1986mm.

[0105] Calculate u 35 :Since the verticality of the vertical rod of the limit trolley is no more than 0.05mm, it is assumed to obey uniform distribution, including factor From the corresponding formula we can get

[0106] Calculate u c3 : Among them, c1 to c5 take the value of 1, and the final calculation is u c2 =0.6109mm.

[0107] Expanded uncertainty of the calculated limit transverse dimension: U = u ci ×k, where k is 2, and U is calculated to be 0.6109×2=1.2218mm.

[0108] Calculation conclusion: Since the maximum allowable error of the measuring trolley's limit lateral dimension is -3~0mm, the expanded uncertainty of the measuring trolley's measurement of the limit lateral dimension should not be greater than the half-width value of the maximum allowable error interval, that is, 1.5mm. The gauge measurement U=1.2218mm of the measuring trolley is less than 1.5mm, which meets the measurement requirements.

[0109] Furthermore, the measuring trolley further includes an inclination sensor, which is used to obtain an angle α between the top surface of the actual track 200 and the horizontal plane;

[0110] The limit dimension formula in step 2 includes the theoretical calculated superelevation value H of track 200,

[0111] H = 1505 × sin (α);

[0112] u in step 3 ci Including the calculation of the ultra-high combined standard uncertainty u of the track 200 c2 ,

[0113]

[0114] Among them, c1 to c4 are sensitivity coefficients, u 21 The uncertainty introduced by the ultra-high measurement repeatability or measurement resolution, u 22 The uncertainty introduced by the measurement indication error of the inclination sensor, u 23 The uncertainty introduced by the flatness of the running wheel, u 24 The standard uncertainty introduced by the difference in expansion coefficient between the sleepers of track 200 and the superelevation measurement structure of the measuring trolley rail.

[0115] Specifically, the Track 200 superelevation measurement model considers u 21 to u 24 The deviation involved fully considers the errors caused by the relevant components, and thus better evaluates the correctness of the numerical value of the track gauge measurement. Among them, the laser distance measurement module is a prior art and will not be described in detail.

[0116] When conducting uncertainty analysis on superelevation measurement of track 200, the specific calculation process is analogous to the calculation and analysis steps of track gauge. First, the measuring trolley is used to measure the track gauge 10 times under repeatable conditions, and the following table data is obtained.

[0117] n(number of times) 1 2 3 4 5 6 7 8 9 10 H(mm) 49.9 50.0 49.9 50.0 49.9 50.0 49.9 50.0 50.0 50.0

[0118] Calculate the uncertainty u introduced by ultra-high measurement repeatability a2 :Then substitute the data into s i (L), the experimental standard deviation of the super-high size is s3(L) = 0.0516 mm, then u a2 =s3(L)=0.0516mm.

[0119] Calculation of uncertainty u introduced by the repeatability of ultra-high-size measurement resolution b2 :Since the measurement resolution of the measuring car is 0.1, then a=0.05mm, assuming uniform distribution, including factor From the corresponding formula we can know: Because u a2 Greater than u b2 , so the uncertainty introduced by the resolution is negligible, then u 21 =u a2 =0.0516mm.

[0120] Calculate u 22 :Since the maximum indication error of the laser ranging module is ±0.003°, the half width is 1505×sin(0.003 / 180×π)=0.0788mm, assuming uniform distribution, the inclusion factor From the corresponding formula we can get

[0121] Calculate u 23 :Since the working busbars of each running wheel should be in the same plane, its flatness should not be greater than 0.2mm. Assuming that it obeys uniform distribution, including factors From the corresponding formula we can get

[0122] Calculate u 24 :Since the expansion coefficient of the sleeper of track 200 is α2=11.5×10 -6 / ℃, the ultra-high measurement structure of the measuring trolley is made of 304 stainless steel, and its corresponding expansion coefficient α1=17.2×10 -6 / ℃, in actual measurement, there is a certain temperature difference between the sleeper and the gauge, and it falls anywhere in the estimated range (-3~3)℃ with equal probability, that is, the half width a is 100×(17.2-11.5)×10 -6 ×3=0.0017mm, assuming triangular distribution, including factor From the corresponding formula we get

[0123] Calculate u c2 : Among them, c1 to c4 take the value of 1, and the final calculation is u c2 =0.0869mm.

[0124] Calculate the ultra-high expanded uncertainty: U = u ci ×k, where k is 2, and U is calculated to be 0.0869×2=0.1738mm.

[0125] Calculation conclusion: Since the maximum allowable error of the superelevation measurement of the measuring trolley is ±1mm, the expanded uncertainty of the superelevation measurement of the measuring trolley should not be greater than the half-width value of the maximum allowable error interval, that is, 1mm. The track gauge measurement U=0.1738mm of the measuring trolley is less than 1mm, which meets the measurement requirements.

[0126] See also Figure 1 and Figure 2 , further, the measuring trolley also includes a vertical rod, on which two laser distance measuring modules are movably arranged at intervals, the laser distance measuring modules and the measuring wheel are located on the same vertical plane, and the laser distance measuring modules are used to measure the distance l4 from the laser starting point to the platform 100. In step 1, the laser module measures the distance to the edge of the platform 100 once per unit moving step, records relevant data, and determines whether the laser just hits the top surface of the platform 100 according to the data;

[0127] The limit dimension formula in step 2 also includes the calculation of the limit vertical dimension L3,

[0128] L3=l6+l7, wherein l6 is the travel distance of the laser module, and l7 is the vertical height of the laser to the track surface of the track 200.

[0129] Furthermore, if the track surface of the track 200 is horizontal or the inner rail is superelevated, when the reading of the laser ranging module is 0 mm or greater than 2000 mm, it is determined that the laser just hits the top surface of the platform 100;

[0130] If the outer rail of the track 200 is superelevated, a calculation value T is introduced to determine whether the laser point just hits the top surface of the platform 100. When the value of T is greater than the threshold value 10, it is determined that the laser just hits the top surface of the platform 100, as shown in the following formula:

[0131] Among them, β2 is the current reading of the laser ranging module, β1 is the previous reading of the laser ranging module, and α is the unit moving step of the laser ranging module.

[0132] Furthermore, the laser ranging module is connected to a slide module for driving it to move in a vertical direction, and the slide module includes a driving motor;

[0133] u in step 3 ci It also includes the calculation of the uncertainty of the vertical dimension u c4 ,

[0134]

[0135] Among them, c1 to c5 are sensitivity coefficients, u 41 The uncertainty introduced by the repeatability or measurement resolution of the limit vertical dimension measurement, u 42 is the uncertainty introduced by the indication error of the drive motor, u 43 The uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 44 The uncertainty introduced by the verticality of the vertical rod, u 44 The uncertainty introduced by the difference in expansion coefficient between the platform 100 and the vertical rod.

[0136] Specifically, the measurement model of the vertical dimension of the limit considers u 41 to u 45 The deviations involved fully consider the errors caused by related components, and thus better evaluate the correctness of the measured values ​​of the vertical dimension of the limit. Among them, the laser ranging module and the slide module are existing technologies and will not be described in detail.

[0137] When conducting uncertainty analysis on the limit vertical dimension measurement, the specific calculation process is similar to the calculation and analysis steps of the track gauge. First, the measuring trolley is used to measure the parameters 10 times under repeatable conditions, and the following table data is obtained.

[0138]

[0139] Uncertainty u introduced by repeatability of vertical dimension measurement of calculation limit a3 :Then substitute the data into s i (L), the experimental standard deviation of the limit vertical dimension is s4(L) = 0.0483mm, then u a3 =s4(L)=0.0483mm.

[0140] Uncertainty u introduced by the measurement resolution of the vertical dimension of the calculated limit b2 :Since the measurement resolution of the measuring car is 0.1, then a=0.05mm, assuming uniform distribution, including factor From the corresponding formula we can know: Because u a2 Greater than u b2 , so the uncertainty introduced by the resolution is negligible, then u 41 =u a2 =0.0483mm.

[0141] Calculate u 42 :Since the maximum indication error of the drive motor is ±0.05°, its half-width formula is: Among them, Y is the calculated value of the moving distance of the laser ranging module, n is the rotation angle of the drive motor, and R is the radius of the drive gear of the slide module. The calculated value is Y = 0.0262 mm. Assuming that it obeys uniform distribution, the inclusion factor From the corresponding formula we can get

[0142]

[0143] Calculate u 43 :It can be seen that the verticality between the laser module and the vertical rod is no more than 0.05mm. Assuming that it obeys uniform distribution, it is assumed that it obeys uniform distribution, including factors From the corresponding formula we can get

[0144] Calculate u 44 :It can be seen that the verticality of the vertical rod of the measuring trolley is no more than 0.05mm. Assuming that it obeys uniform distribution, it is assumed that it obeys uniform distribution, including factors From the corresponding formula we can get

[0145] Calculate u 45:Since the expansion coefficient of the sleeper of track 200 is α2=11.5×10 -6 / ℃, the vertical rod is made of aluminum alloy, and its corresponding expansion coefficient is α1=22.6×10 -6 / ℃, in actual measurement, there is a certain temperature difference between the sleeper and the gauge, and it falls anywhere in the estimated range (-3~3)℃ with equal probability, that is, the half width a is 1350×(22.6-11.5)×10 -6 ×3=0.045mm, assuming triangular distribution, including factor From the corresponding formula we get

[0146] Calculate u c4 : Among them, c1 to c5 take the value of 1, and the final calculation is u c4 =0.0576mm.

[0147] Calculate the ultra-high expanded uncertainty: U = u ci ×k, where k is 2, and U is calculated to be 0.0576×2=0.1152mm.

[0148] Calculation conclusion: Since the maximum allowable error of the limit vertical dimension measured by the measuring trolley is 2~0mm, the expanded uncertainty of the limit vertical dimension measured by the measuring trolley should not be greater than the half-width value of the maximum allowable error interval, that is, 1mm. If the limit dimension measurement U=0.1152mm of the measuring trolley is less than 1mm, the measurement requirements are met.

[0149] Through the above steps, the limit dimensions of the platform (including gauge, superelevation, limit lateral dimensions and limit vertical dimensions) can be correctly evaluated, which is conducive to improving the accuracy and reliability of the measurement data, thereby forming a standardized evaluation process for the limit dimension measurement of the platform.

[0150] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0151] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for evaluating platform clearance measurement error, characterized in that: include: Step 1: Using a measuring trolley to measure various parameter values ​​of various limiting dimensions of the platform (100); Step 2: Substitute the parameter value obtained in step 1 into the corresponding limit dimension formula, and calculate the value of the corresponding limit dimension; Step 3: Move the measuring vehicle, perform repeated measurements at a given unit step length, and record the data; Step 4: Establish a measurement model, calculate the uncertainty of each component of the measurement model, and calculate the total combined standard uncertainty u ci , and calculate the expanded uncertainty U, U=u ci ×k, where k is the inclusion factor and i is the serial number of each limit dimension; Step 5: Compare the value of U calculated in step 4 with the half-width value of the maximum allowable error interval of the corresponding limit dimension. If the calculated value of U is smaller than the half-width value, it can be determined that the measured limit dimension parameters are qualified.

2. A platform clearance measurement error evaluation method according to claim 1, characterized in that: include: The measuring trolley comprises running wheels and a crossbeam, the running wheels are used to roll in contact with the track (200), two ends of the crossbeam are respectively provided with a displacement sensor and a measuring wheel, the measuring wheel is in contact with the inner wall of the track (200), and the displacement sensor is used to obtain a distance l1 between an end point of the crossbeam and a contact point; The limit size formula in step 2 is used to calculate the track gauge L1. L1=l3+2×l1, where l3 is the length of the beam; u in step 3 ci Including the combined standard uncertainty u of the calculated track gauge c1 , Among them, c1 to c7 are sensitivity coefficients, u 11 The uncertainty introduced by the repeatability or measurement resolution of the track gauge measurement, u 12 is the uncertainty introduced by the measurement indication error of the displacement sensor, u 13 is the uncertainty introduced by the effective height deviation between the contact point and the lowest generatrix of the running wheel, u 14 is the uncertainty introduced by the flatness of the running wheel, u 15 The uncertainty introduced by the wear of the measuring wheel, u 16 The uncertainty introduced by the runout of the working surface of the measuring wheel to its own axis, u 17 The uncertainty is introduced by the difference in expansion coefficient between the sleepers of the track (200) and the measuring structural parts of the measuring trolley.

3. A platform clearance measurement error evaluation method according to claim 2, characterized in that: include: Uncertainty u introduced by repeatability calculation of track gauge measurement based on type A analysis a , Calculate the uncertainty u introduced by the track gauge measurement resolution based on Class B analysis b , then u 11 =max[u a ,u b ]; Calculate u a The steps include: measuring n sets of experimental data and recording the data values ​​L i , and calculate the mean value of the data The experimental standard deviation s is calculated by the Bessel formula. i (L),u a =s i (L), as follows: Calculate u b The steps include: Where a is the half-width of the allowable error of the measurement calculation accuracy, and k is the coverage factor.

4. A platform clearance measurement error evaluation method according to claim 2, characterized in that: include: Calculate u based on Class B analysis 12 to u 17 , as follows: Among them, i is the serial number of each uncertainty, a i is the half-width value of the allowable error of the corresponding serial number measurement calculation accuracy, and k is the coverage factor.

5. A platform clearance measurement error evaluation method according to claim 2, characterized in that: include: The measuring trolley also includes a vertical rod, on which two laser distance measuring modules are arranged at intervals, the laser distance measuring modules and the measuring wheel are located on the same vertical plane, and the laser distance measuring modules are used to measure the distance l4 from the laser starting point to the platform (100); The limit dimension formula in step 2 also includes calculating the limit lateral dimension L2, Wherein, l5 is the distance between the laser starting point and the contact point between the measuring wheel and the track (200); u in step 3 ci It also includes the combined standard uncertainty u of the calculated limit transverse dimension c3 , Among them, c1 to c5 are sensitivity coefficients, u 31 The uncertainty introduced by the repeatability or measurement resolution of the limit lateral dimension measurement, u 32 is the uncertainty introduced by the measurement indication error of the laser ranging module, u 33 is the uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 34 The uncertainty introduced by the track gauge measurement, u 35 Uncertainty introduced for the verticality of the vertical rod.

6. A platform clearance measurement error evaluation method according to claim 2, characterized in that: include: The measuring vehicle further comprises an inclination sensor, wherein the inclination sensor is used to obtain an angle α between the top surface of the actual track (200) and the horizontal plane; The limiting dimension formula of step 2 includes the theoretical calculated value H of the superelevation of the track (200), H = 1505 × sin (α); u in step 3 ci Including the ultra-high combined standard uncertainty u of the calculated orbit (200) c2 , Among them, c1 to c4 are sensitivity coefficients, u 21 The uncertainty introduced by the ultra-high measurement repeatability or measurement resolution, u 22 is the uncertainty introduced by the measurement indication error of the inclination sensor, u 23 is the uncertainty introduced by the flatness of the running wheel, u 24 The standard uncertainty introduced by the difference in expansion coefficient between the sleeper of the track (200) and the superelevation measurement structural member of the measuring trolley rail.

7. A platform clearance measurement error evaluation method according to claim 1, characterized in that: include: The measuring trolley further comprises a vertical rod, on which two laser distance measuring modules are movably arranged at intervals, the laser distance measuring modules and the measuring wheel being located on the same vertical plane, the laser distance measuring modules being used to measure the distance l4 from the laser starting point to the platform (100), and in step 1, the laser module performs distance measurement on the edge of the platform (100) once per unit moving step, records relevant data, and determines whether the laser just hits the top surface of the platform (100) based on the data; The limit dimension formula in step 2 also includes calculating the limit vertical dimension L3, L3=l6+l7, wherein l6 is the travel distance of the laser module, and l7 is the vertical height of the laser to the track surface.

8. A platform clearance measurement error evaluation method according to claim 7, characterized in that: include: If the track surface of the track (200) is horizontal or the inner track is superelevated, and the reading of the laser distance measurement module is 0 mm or greater than 2000 mm, it is determined that the laser just hits the top surface of the platform (100); If the outer rail of the track (200) is superelevated, a calculation value T is introduced to determine whether the laser point just hits the top surface of the platform (100). When the value of T is greater than a threshold value of 10, it is determined that the laser just hits the top surface of the platform (100), as shown in the following formula: Wherein, β2 is the current reading of the laser ranging module, β1 is the last reading of the laser ranging module, and α is the unit moving step of the laser ranging module.

9. A platform clearance measurement error evaluation method according to claim 7, characterized in that: include: The laser ranging module is connected to a slide module for driving it to move in a vertical direction, and the slide module includes a driving motor; u in step 3 ci It also includes the calculation of the uncertainty of the vertical dimension u c4 , Among them, c1 to c5 are sensitivity coefficients, u 41 The uncertainty introduced by the repeatability or measurement resolution of the limit vertical dimension measurement, u 42 is the uncertainty introduced by the indication error of the drive motor, u 43 is the uncertainty introduced by the verticality of the laser ranging module and the vertical rod, u 44 is the uncertainty introduced by the verticality of the vertical rod, u 44 The uncertainty introduced by the difference in expansion coefficient between the platform (100) and the vertical rod.

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