CN106184284A - Railway wheelset diameter automatic measurement method and system based on the scanning of line laser multi-section - Google Patents

Abstract

The invention provides a kind of Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section, comprise the following steps: (1) obtains the discrete point set of the tread wheel rim on Train Wheel different radii direction；(2) described discrete point set is fitted to integrity profile curve respectively；(3) solve and obtain organizing tread radius more；(4) first filter out the tread radius that the relatively large Laser feedback sharpness value of N group is corresponding, then from N group tread radius, filter out the tread radius that the bigger Laser feedback intensity level of M group is corresponding；(5) tread radius corresponding for Laser feedback intensity level bigger for M group is taken arithmetic mean and be worth to average tread radius.The Railway wheelset diameter automatic measurement method and system based on the scanning of line laser multi-section that the present invention provides, its certainty of measurement is high.

Description

Based on line laser multi-section scanning Railway wheelset diameter automatic measurement method and System

Technical field

The present invention relates to a kind of Railway wheelset diameter automatic measurement method and system based on the scanning of line laser multi-section, Particularly relate to a kind of method and system measuring Railway wheelset diameter by choosing laser signal-noise ratio optimum.

Background technology

Railway wheelset periphery is made up of with tread two function curved surface wheel rim, and tread contacts with rail and realizes Inhaul operation, It is provided commonly for guiding with wheel rim.Therefore, wheel all can produce abrasion, only to the surface portion contacted with rail generation on periphery The circular arc on wheel rim top is the part not contacted with rail, there are not abrasion, and is in operation and is always maintained at stable dimensioning Very little.The diameter of wheel rim is the size that Train Wheel is critically important, and prior art is to use Train Wheel footpath chi to Railway wheelset by artificial Diameter is measured or is detected by Railway wheelset physical dimension on-line measurement system, and the certainty of measurement in wheel footpath all exists 0.5mm。

Summary of the invention

Based on above not enough, the technical problem to be solved in the present invention is to provide a kind of row based on the scanning of line laser multi-section Wheel is to diameter automatic measurement method and system, and its certainty of measurement is high.

In order to solve above technical problem, present invention employs techniques below scheme:

A kind of Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section, comprises the following steps:

(1) discrete point set of the tread wheel rim on acquisition Train Wheel different radii direction；

(2) described discrete point set is fitted to integrity profile curve respectively；

(3) solve and obtain organizing tread radius more；

(4) the tread radius that the relatively large Laser feedback sharpness value of N group is corresponding is first filtered out, then from N group tread radius In filter out the tread radius that the bigger Laser feedback intensity level of M group is corresponding；

(5) tread radius corresponding for Laser feedback intensity level bigger for M group is taken arithmetic mean and is worth to average tread half Footpath.

The discrete point set of the tread wheel rim on described acquisition Train Wheel different radii direction includes:

(11) coordinate of the tread wheel rim on acquisition Train Wheel different radii direction；

(12) described coordinate is fused into discrete point set.

The coordinate of the tread wheel rim on described acquisition Train Wheel different radii direction includes:

It is respectively provided with laser displacement sensor near the tread of Train Wheel and the position of wheel rim in orbit, enters from Train Wheel Entering laser displacement sensor effective range and stop to leaving laser displacement sensor effective range, two laser displacements pass Sensor synchronizes to obtain the own coordinate system coordinate of the tread wheel rim on Train Wheel different radii direction respectively；

Described own coordinate system Coordinate Conversion is become middle coordinate system coordinate.

Described middle coordinate system coordinate is become to include described own coordinate system Coordinate Conversion:

Set up own coordinate and be tied to the transformational relation of middle coordinate system；

It is middle coordinate system coordinate according to described transformational relation by own coordinate system Coordinate Conversion.

Described described discrete point set fitted to integrity profile curve respectively include:

Discrete point sectional is fitted to sectional curve；

Described subsection curve drafting is become integrity profile curve.

Including: discrete point set acquisition module, contour curve fitting module, contour curve choose module and radius solves mould Block, radius screening module and average tread radius solve module, wherein,

Discrete point set acquisition module, for obtaining the discrete point set of the tread wheel rim on Train Wheel different radii direction；

Contour curve fitting module, for fitting to integrity profile curve respectively by described discrete point set；

Contour curve chooses module, is used for the integrity profile curve selecting number of effective points most；

Radius solves module, is used for solving and obtains tread radius；

Radius screening module, for first filtering out the tread radius that the relatively large Laser feedback sharpness value of N group is corresponding, then The tread radius that the relatively large Laser feedback intensity level of M group is corresponding is filtered out from N group tread radius；

Average tread radius solves module, for tread radius corresponding for Laser feedback intensity level bigger for M group is taken calculation Number meansigma methods obtains average tread radius.

Described contour curve is chosen module and is included coordinate acquiring unit, coordinate integrated unit, wherein,

Coordinate acquiring unit, for obtaining the coordinate of the tread wheel rim on Train Wheel different radii direction；

Coordinate integrated unit, is fused into discrete point set by described coordinate.

Described coordinate acquiring unit includes two laser displacement sensors and coordinate transformation unit,

Laser displacement sensor, is separately positioned on the inner side and outer side of described Train Wheel, and described laser displacement sensor divides Tong Bu not obtain the own coordinate system coordinate of tread wheel rim on Train Wheel different radii direction；

Coordinate transformation unit, becomes middle coordinate system coordinate by described own coordinate system Coordinate Conversion.

Described coordinate transformation unit includes,

Measurement model subelement, is tied to the transformational relation of middle coordinate system for setting up own coordinate；

Conversion subelement, for being middle coordinate system coordinate according to described transformational relation by own coordinate system Coordinate Conversion.

Described contour curve fitting module includes:

Subsection curve drafting unit, for fitting to sectional curve by discrete point sectional；

Contour curve fitting unit, for becoming integrity profile curve by described subsection curve drafting.

Using above technical scheme, the present invention achieves techniques below effect:

The Railway wheelset diameter automatic measurement method and system based on the scanning of line laser multi-section that the present invention provides, its The certainty of measurement that can reach is taken turns online higher than existing train and physical dimension measurement technology and general maintenance wheel footpath is measured skill The precision of art, and simple in construction is easy for installation.

Accompanying drawing explanation

Fig. 1 is the flow chart of the Railway wheelset diameter automatic measurement method that the present invention scans based on line laser multi-section；

Laser displacement in the Railway wheelset diameter automatic measurement method that Fig. 2 is the present invention to be scanned based on line laser multi-section Sensor position relative with Train Wheel top view；

Laser displacement in the Railway wheelset diameter automatic measurement method that Fig. 3 is the present invention to be scanned based on line laser multi-section Sensor measurement scope schematic diagram；

Laser displacement in the Railway wheelset diameter automatic measurement method that Fig. 4 is the present invention to be scanned based on line laser multi-section The perspective view of sensor；

Fig. 5 a and 5b is respectively the Railway wheelset diameter automatic measurement method that the present invention scans based on line laser multi-section Laser displacement sensor A and B be Coordinate Conversion schematic diagram；

After the Railway wheelset diameter automatic measurement method that Fig. 6 is the present invention to be scanned based on line laser multi-section merges The discrete point set schematic diagram of the profile of tread and wheel rim；

By discrete point in the Railway wheelset diameter automatic measurement method that Fig. 7 is the present invention to be scanned based on line laser multi-section The integrity profile curve that collection matching is formed；

Radius measurement in the Railway wheelset diameter automatic measurement method that Fig. 8 is the present invention to be scanned based on line laser multi-section Geometry location illustraton of model；

Fig. 9 is the composition structure of the Railway wheelset diameter automatic measuring system that the present invention scans based on line laser multi-section Schematic diagram.

Detailed description of the invention

As Figure 1-Figure 5, the Railway wheelset diameter automatic measurement method that the present invention scans based on line laser multi-section Including with

Lower step:

S101: the discrete point set of the tread wheel rim on acquisition Train Wheel different radii direction；

Concrete, as in figure 2 it is shown, be respectively provided with laser displacement near the tread of Train Wheel and the position of wheel rim in orbit Sensor, wherein, the laser displacement sensor being numbered A is arranged in orbit near the position of wheel rim, is numbered the laser position of B Displacement sensor is arranged in orbit near the position of tread, and laser displacement sensor A and laser displacement sensor B together decides on Test surface is 45 ° with the inclination angle of track horizontal plane, it is also possible to for other angle.Fig. 3 is the projection of laser displacement sensor A and B Schematic diagram, laser displacement sensor A and B synchronizes the own coordinate system coordinate of fetching portion tread and wheel rim respectively, from Train Wheel The effective range entering laser displacement sensor A and B is stopped to the effective range leaving laser displacement sensor A and B, Two laser displacement sensors synchronize to obtain the own coordinate system coordinate of the tread wheel rim on Train Wheel different radii direction respectively.

Laser displacement sensor based on laser triangulation principle, internal optical system by laser diode and CCD line Property sensing element composition, the laser that lasing light emitter is launched forms a laser band at tread and wheel rim, and its reflection light is at an angle Reflex to CCD linear response element, after the integrated circuit of sensor processes optical displacement data, obtain tread profile coordinate points. Measurement value sensor is displayed by X-Y datagram, and the most each point of measuring can export two values, and a value is in measuring Distance X of heart line, a value is distance Y from sensor lasing light emitter, and in Fig. 3, region C is having of laser displacement sensor A or B Effect measurement scope, wherein La is the least effective dose (LED) journey of horizontal X, and Le is the maximal effective dose journey of horizontal X, Lm be longitudinal Y Little useful range, Ln is the maximal effective dose journey of longitudinal Y.

Except transmission, each measures in addition to the two-dimensional coordinate of sampled point laser displacement sensor, and also transmission Laser feedback is at CCD On intensity level and sharpness value.Intensity level can be used for judging that the laser-bounce of this sampling is the most reliable, and intensity level height represents sharp Luminous reflectance reception good, the acutance detection of CCD can be used for evaluating the situation that affects of the interference light of laser sampling environment, and sharpness value is high Representing that interference light impact is little, sampled data credibility is higher.

Owing to sensor is installed on track both sides, the lateral displacement caused between the trip between wheel track, real-time full profile in addition Curve cannot overlap naturally with static criteria profile.Further, due to the installation site of two laser displacement sensors and horizontal plane And track all has a certain degree, the curve that the own coordinate system coordinate recorded is formed will necessarily produce distortion, therefore need to be to former The own coordinate system coordinate begun is corrected.As shown in figure 5a and 5b, the rectification to own coordinate system coordinate is rotated by coordinate Realize, rotated by coordinate and described own coordinate system Coordinate Conversion is become middle coordinate system coordinate.Concrete main by two steps Suddenly complete, first, set up own coordinate and be tied to the transformational relation model of middle coordinate system；Will be own further according to described transformational relation Coordinate system Coordinate Conversion is middle coordinate system coordinate.

Transformational relation model is as follows:

$\left\{\begin{array}{c}{u_n}^{\left(3\right)}=\sqrt{{x_n}^{{\left(3\right)}^2}+{y_n}^{{\left(3\right)}^2}}\sin (\mathrm{\θ}+{\mathrm{\β}}_3)={x_n}^{\left(3\right)}{\mathrm{cos\β}}_3+{y_n}^{\left(3\right)}{\mathrm{sin\β}}_3\\ {v_n}^{\left(3\right)}=\sqrt{{x_n}^{{\left(3\right)}^2}+{y_n}^{{\left(3\right)}^2}}\cos (\mathrm{\θ}+{\mathrm{\β}}_3)={y_n}^{\left(3\right)}{\mathrm{cos\β}}_3-{x_n}^{\left(3\right)}{\mathrm{sin\β}}_3\end{array}\right.$

$\left\{\begin{array}{c}{u_n}^{\left(4\right)}=\sqrt{{x_n}^{{\left(4\right)}^2}+{y_n}^{{\left(4\right)}^2}}\sin ({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_4)={x_n}^{\left(4\right)}{\mathrm{cos\β}}_2-{y_n}^{\left(4\right)}{\mathrm{sin\β}}_2\\ {v_n}^{\left(4\right)}=\sqrt{{x_n}^{{\left(4\right)}^2}+{y_n}^{{\left(4\right)}^2}}\cos ({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_4)={y_n}^{\left(4\right)}{\mathrm{cos\β}}_2+{x_n}^{\left(4\right)}{\mathrm{sin\β}}_2\end{array}\right.$

In formula, (x_n ⁽³⁾,y_n ⁽³⁾) it is the sensing point own coordinate system x in sensors A⁽³⁾o⁽³⁾y⁽³⁾On coordinate, (x_n ⁽⁴⁾, y_n ⁽⁴⁾) it is the sensing point own coordinate system x at sensor B⁽⁴⁾o⁽⁴⁾y⁽⁴⁾On coordinate, θ is sensing point and the y of sensors A⁽³⁾Axle Angle, θ ＇ is sensing point and the y of sensor 4⁽⁴⁾The angle of axle, (u_n ⁽³⁾,v_n ⁽³⁾) it is that the sensing point of sensor 3 is in middle coordinate It is u⁽³⁾o⁽³⁾v⁽³⁾Interior coordinate figure, (u_n ⁽⁴⁾,v_n ⁽⁴⁾) it is that the sensing point of sensor 4 is in middle coordinate system u⁽⁴⁾o⁽⁴⁾v⁽⁴⁾Interior seat Scale value.The sensing point detected by laser displacement sensor A and B obtains after the coordinate of own coordinate system is according to above-mentioned model conversion Sensing point is at the coordinate of middle coordinate system.

All can only detect the coordinate of the profile of part tread and wheel rim due to sensors A and B, therefore need will swash further The sensing point of Optical displacement sensor A and B merges at the coordinate of middle coordinate system, to obtain the profile of whole tread and wheel rim Discrete point set.Namely the sensing point of laser displacement sensor A and B is all transformed into benchmark seat at the coordinate of middle coordinate system In mark system.The fusion of coordinate is realized by coordinate Fusion Model.

Coordinate Fusion Model is as follows:

u_n=u_n ⁽³⁾ u_n=u_n ⁽⁴⁾+Δu

v_n=v_n ⁽⁴⁾ v_n=v_n ⁽⁴⁾+Δv

(u in formula_n,v_n) it is that the sensing point of laser displacement sensor A and B is fused at benchmark at the coordinate of middle coordinate system Coordinate after coordinate system, u Δ is that the initial point of the middle coordinate system of laser displacement sensor B exists relative to the initial point of the frame of reference The axial skew of U, v Δ be the initial point of the middle coordinate system of laser displacement sensor B relative to the initial point of the frame of reference at V Axial skew.Frame of reference initial point overlaps with the middle coordinate system initial point of sensors A, therefore the middle coordinate of sensors A The initial point of system is 0 relative to the side-play amount of the initial point of the frame of reference.Tread after fusion and the discrete point set of the profile of wheel rim As shown in Figure 6.

S102: described discrete point set is fitted to integrity profile curve respectively；

Specifically, first discrete point sectional is fitted to sectional curve；Again described subsection curve drafting is become integrity profile Curve.

Curve shown in Fig. 7 is the integrity profile curve formed by discrete point set matching, and during due to Wheel Rail Contact, Train Wheel is leaned on There is not abrasion and deformation in nearly track one side end face and rail level, therefore on the integrity profile curve recorded, respective column wheel is near rail The linear feature of side, road endface position is the most obvious, this end face straight line is set to the first datum line l of wheel, from wheel rim end face The point of 70mm is set to tread point a, and wheel footpath is defined as a radius r for a place circle, and the summit of wheel rim is set to n point, n point place circle Radius is R.Point after coordinate merges is discrete point, therefore some a, n are the most just included in.Accordingly, it would be desirable to after merging Discrete point set matching obtains the integrity profile curve of tread and wheel rim, and then obtains the coordinate figure of corresponding point a on curve, n.According to The coordinate figure of some a, n can calculate radius r, can be specifically described further after circular.Owing to tread contour is taken turns Wide complexity, it is difficult to a curve matching whole tread profile determined, therefore first a range of discrete point is carried out Piecewise fitting becomes sectional curve；Described subsection curve drafting is become integrity profile curve again, thus improves datum mark coordinate figure and carry The degree of accuracy taken.

S103: solve and obtain tread radius；

Fig. 8 is radius measurement geometry location illustraton of model, obtains some a, a n according to the integrity profile curve that number of effective points is most and exists Accurate coordinates value in coordinate system uov, such that it is able to draw corresponding n point L1 value, the i.e. v coordinate of n point, and the L2 value of a point, i.e. The v coordinate of a point.

Precise radius R of definition wheel rim top n point circumference, precision 0.01mm, owing to this circle diameter is in running Abrasion change will not occur, therefore can be as stable high precision reference, i.e. R for it is known that utilize data host data base to store Xuan is repaiied the sized data of processing by corresponding wheel.Take turns during by measured zone, make wheel that wheel rim to be climbed up wheel rim and measure supporting track, Order wheel height same to wheel rim circumference bottom position and sensor measurement zero, forms such as the geometry location model of Fig. 7, passes through R, L1, L2, such that it is able to extrapolate the value of the radius r of a point.Calculate derivation as follows:

$H1=\frac{\sqrt{2}}{2}L1$

$H2=\frac{\sqrt{2}}{2}L2$

r²=(R-H2)²+S2²

$S2=S1-\frac{\sqrt{2}}{2}(L1-L2)$

S1²=R²-(R-H1)²

$S{1}^2=R^2-{(R-\frac{\sqrt{2}}{2}L1)}^2$

$r^2={(R-\frac{\sqrt{2}}{2}L2)}^2+{(S1-\frac{\sqrt{2}}{2}(L1-L2\left)\right)}^2$

$r^2={(R-\frac{\sqrt{2}}{2}L2)}^2+{(\sqrt{R^2-{(R-\frac{\sqrt{2}}{2}L1)}^2}-\frac{\sqrt{2}}{2}(L1-L2\left)\right)}^2$

S104: first filter out the tread radius that the bigger Laser feedback sharpness value of N group is corresponding, then filter out M group from which The tread radius that bigger Laser feedback intensity level is corresponding；

S105: tread radius corresponding for Laser feedback intensity level bigger for M group is averaged and obtains average tread radius.

In the present embodiment, take turns entering laser scanning overlay area until wheel tread leaves and reaches sensor and effectively measure Only, sensor will obtain the radius value ri of ai point, totally 30 groups of data in a series of rolling circumference to range position.Sensor simultaneously Also can feed back each group of Laser Measurement feedback intensity value corresponding to sampled data and sharpness value, to Laser feedback sharpness value from greatly to Little arrange, filter out corresponding ri, the i.e. N=15 of sharpness value coming front 15, then these 15 groups of data are pressed intensity level from greatly Arranging to little, therefrom screening comes corresponding ri, the i.e. M=10 of Laser feedback intensity level of front 10, the 10 groups of ri that will obtain Do arithmetic average and calculate r, thus reduce random error, improve the measuring precision and stability.

This technology by for the self diagnosis identification of two-dimensional laser displacement sensor data, screening feedback intensity value and What sharpness value was more excellent measure signal, for taking turns the survey calculation in footpath, is effectively increased the reliability of measurement.

Fig. 9 provides a kind of Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section, including: from Scatterplot collection acquisition module 201, contour curve fitting module 202, contour curve choose module 203 and radius solves module 204, Wherein,

Discrete point set acquisition module 201, for obtaining the discrete point set of the tread wheel rim on Train Wheel different radii direction；

Contour curve fitting module 202, for fitting to integrity profile curve respectively by described discrete point set；

Contour curve chooses module 203, for selecting the integrity profile curve of flange height value minimum；

Radius solves module 204, is used for solving and obtains tread radius；

Radius screening module 205, for filtering out the tread radius that the bigger Laser feedback sharpness value of N group is corresponding, then from Wherein filter out the tread radius that the bigger Laser feedback intensity level of M group is corresponding；

Average tread radius solves module 206, for being taken by tread radius corresponding for Laser feedback intensity level bigger for M group Meansigma methods obtains average tread radius.

Further, discrete point set acquisition module 201 includes coordinate acquiring unit, coordinate integrated unit, wherein,

Coordinate acquiring unit, for obtaining the coordinate of the tread wheel rim on Train Wheel different radii direction；

Coordinate integrated unit, is fused into discrete point set by described coordinate.

Further, coordinate acquiring unit includes two laser displacement sensors and coordinate transformation unit,

Laser displacement sensor, is separately positioned on the inner side and outer side of described Train Wheel, and described laser displacement sensor divides Tong Bu not obtain the own coordinate system coordinate of tread wheel rim on Train Wheel different radii direction；

Coordinate transformation unit, becomes middle coordinate system coordinate by described own coordinate system Coordinate Conversion.

Further, coordinate transformation unit includes,

Measurement model subelement, is tied to the transformational relation of middle coordinate system for setting up own coordinate；

Conversion subelement, for being middle coordinate system coordinate according to described transformational relation by own coordinate system Coordinate Conversion.

Further, contour curve fitting module 202 includes:

Subsection curve drafting unit, for fitting to sectional curve by discrete point sectional；

Contour curve fitting unit, for becoming integrity profile curve by described subsection curve drafting.

The Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section that the present invention provides can reach Certainty of measurement take turns the essence that physical dimension measurements technology and general maintenance are taken turns footpath measurement technology online higher than existing train Degree, and simple in construction is easy for installation.

Finally it is noted that these are only the preferred embodiments of the present invention, it is not limited to the present invention, although Being described in detail the present invention with reference to embodiment, for a person skilled in the art, it still can be to aforementioned Technical scheme described in each embodiment is modified, or wherein portion of techniques feature carries out equivalent, but all Within the spirit and principles in the present invention, any modification, equivalent substitution and improvement etc. made, should be included in the protection of the present invention Within the scope of.

Claims (10)

1. one kind based on line laser multi-section scanning Railway wheelset diameter automatic measurement method, it is characterised in that: include with Lower step:

(1) discrete point set of the tread wheel rim on acquisition Train Wheel different radii direction；

(2) described discrete point set is fitted to integrity profile curve respectively；

(3) solve and obtain organizing tread radius more；

(4) first filter out the tread radius that the relatively large Laser feedback sharpness value of N group is corresponding, then sieve from N group tread radius Select the tread radius that the relatively large Laser feedback intensity level of M group is corresponding；

(5) tread radius corresponding for Laser feedback intensity level bigger for M group is taken arithmetic mean and be worth to average tread radius.

Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section the most according to claim 1, its Being characterised by, the discrete point set of the tread wheel rim on described acquisition Train Wheel different radii direction includes:

(11) coordinate of the tread wheel rim on acquisition Train Wheel different radii direction；

(12) described coordinate is fused into discrete point set.

Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section the most according to claim 2, its It is characterised by,

The coordinate of the tread wheel rim on described acquisition Train Wheel different radii direction includes:

It is respectively provided with laser displacement sensor near the tread of Train Wheel and the position of wheel rim in orbit, enters from Train Wheel and swash Optical displacement sensor effective range is stopped to leaving laser displacement sensor effective range, two laser displacement sensors Synchronize to obtain the own coordinate system coordinate of the tread wheel rim on Train Wheel different radii direction respectively；

Described own coordinate system Coordinate Conversion is become middle coordinate system coordinate.

Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section the most according to claim 3, its It is characterised by, described becomes middle coordinate system coordinate to include described own coordinate system Coordinate Conversion:

Set up own coordinate and be tied to the transformational relation of middle coordinate system；

It is middle coordinate system coordinate according to described transformational relation by own coordinate system Coordinate Conversion.

Railway wheelset diameter automatic measurement method based on the scanning of line laser multi-section the most according to claim 1, its It is characterised by, described described discrete point set is fitted to integrity profile curve respectively include:

Discrete point sectional is fitted to sectional curve；

Described subsection curve drafting is become integrity profile curve.

6. a Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section, it is characterised in that including: from Scatterplot collection acquisition module, contour curve fitting module, contour curve choose module and radius solves module, radius screening module Module is solved with average tread radius, wherein,

Discrete point set acquisition module, for obtaining the discrete point set of the tread wheel rim on Train Wheel different radii direction；

Contour curve fitting module, for fitting to integrity profile curve respectively by described discrete point set；

Contour curve chooses module, is used for the integrity profile curve selecting number of effective points most；

Radius solves module, is used for solving and obtains tread radius；

Radius screening module, filters out the tread radius that the relatively large Laser feedback sharpness value of N group is corresponding for first, then from N Group tread radius filters out the tread radius that the relatively large Laser feedback intensity level of M group is corresponding；

Average tread radius solves module, for tread radius corresponding for Laser feedback intensity level bigger for M group is taken count flat All it is worth to average tread radius.

Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section the most according to claim 6, its Being characterised by, described discrete point set acquisition module includes coordinate acquiring unit, coordinate integrated unit, wherein,

Coordinate acquiring unit, for obtaining the coordinate of the tread wheel rim on Train Wheel different radii direction；

Coordinate integrated unit, is fused into discrete point set by described coordinate.

Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section the most according to claim 7, its It is characterised by,

Described coordinate acquiring unit includes two laser displacement sensors and coordinate transformation unit,

Laser displacement sensor, is separately positioned on the inner side and outer side of described Train Wheel, and described laser displacement sensor is same respectively Step obtains the own coordinate system coordinate of the tread wheel rim on Train Wheel different radii direction；

Coordinate transformation unit, becomes middle coordinate system coordinate by described own coordinate system Coordinate Conversion.

Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section the most according to claim 8, its Being characterised by, described coordinate transformation unit includes,

Measurement model subelement, is tied to the transformational relation of middle coordinate system for setting up own coordinate；

Conversion subelement, for being middle coordinate system coordinate according to described transformational relation by own coordinate system Coordinate Conversion.

Railway wheelset diameter automatic measuring system based on the scanning of line laser multi-section the most according to claim 6, its Being characterised by, described contour curve fitting module includes:

Subsection curve drafting unit, for fitting to sectional curve by discrete point sectional；

Contour curve fitting unit, for becoming integrity profile curve by described subsection curve drafting.