CN104228875B - Method and device for online detection of size of city rail train wheel set - Google Patents

Abstract

The invention discloses a method and device for online detection of the size of a city rail train wheel set. A system is mainly comprises two 2D laser displacement sensors arranged along a train rail in a mirror symmetric mode, and two laser bijection switches arranged on the two sides of the same rail in a certain geometrical relation. The 2D laser displacement sensors detect and obtain tread contour lines, and the two laser bijection switches detect the wheel passing speed. The rim height and the rim thickness are worked out by extracting the tread contour lines of wheels passing through a detection system according to the geometrical relation. The coordinates of the lowest rim points of the detected tread contour lines of the wheels at different moments are extracted, the coordinates at the different moments are restored to coordinate values at the same moment on the condition that the speed is given, so that the circle where the top points of the rims of the wheels are located is fitted out, the two times of the height of the rims is subtracted from the diameter of the circle of the top points of the rims, and thus the diameters of the wheels are obtained. The method and device for online detection of the size of the city rail train wheel set are low in cost, simple in operation and high in non-contact type measurement precision.

Description

A kind of municipal rail train wheelset profile online test method and device

Technical field

The invention belongs to traffic safety field of engineering technology, particularly a kind of municipal rail train wheelset profile online test method And device.

Background technology

Along with urban rail transit in China fast-developing and a plurality of circuit open operation, the safety of train on-line operation Problem also becomes increasingly conspicuous.Wheel, to being to ensure that train operation on rail and turning to, bears whole quiet, the dynamic loading of vehicle, is Parts particularly important in train traveling system.Therefore, take turns to situation be directly connected to running quality and the safety of train, to it The monitoring in real time of dimensional parameters is the important measures ensureing railcar safety.

For the online measuring technique of wheelset profile, method in early days is to use to survey based on ccd image measurement technology Amount, but the system structure of the method layout is complex and vibrated, environmental effect is big.Along with the development of sensor technology, swash Ligh-ranging has obtained increasingly being widely applied, and the most domestic wheelset profile is measured and all introduced based on laser ranging and shooting The wheelset profile detection method of technology.But, during wheelset profile detects, technological difficulties are to be difficult to accurately quickly obtain wheel To relevant parameter, as high in wheel rim, wheel rim is thick and wheel is to diameter.

Summary of the invention

It is an object of the invention to provide a kind of municipal rail train wheelset profile on-line checking side simple and effective, the most reliable Method and device, use non-contact measurement, and detection speed is fast, easy and simple to handle.

The technical solution realizing the object of the invention is: a kind of municipal rail train wheelset profile online test method, including Following steps:

Step 1, lays sensor: the first laser-correlation switch switchs along train direction of advance successively with the second laser-correlation It is installed on the both sides of same track, and the first laser-correlation switch is parallel with the second laser-correlation switch, peace between the two Dress distance is L₁；Two groups of laser displacement sensors become symmetric mode to be installed on same track both sides, and train depends on along direction of advance Secondary through the first laser-correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch and laser Displacement transducer mounting distance is L₂；Outside track, the Relative vertical distance with inner side laser displacement sensor with track is respectively L₃、L₄, outside track, the angle with inner side laser displacement sensor Yu plumb line is respectively β₁、β₂, with inner side laser outside track Displacement transducer is respectively α with the vertical equity wire clamp angle of direction along ng a path₁、α₂；

Step 2, packet: after two groups of laser displacement sensors sensing point coordinate of detecting wheel output simultaneously, by data Data point is grouped in the array of synchronization by the difference pressing output time；

Step 3, coordinate transform, data fusion: two groups of laser displacement sensors are same by coordinate transform and coordinate translation The output point in one moment is fused on the same coordinate system, and the point after fusion is the discrete point on tread contour line；

Step 4, extracts wheel rim apex coordinate: after merging, the discrete point on synchronization tread contour line is according to coordinate figure Size extract the coordinate points that ordinate value is minimum, this point coordinates is this moment wheel rim apex coordinate；

Step 5, obtains wheel rim height, wheel rim thickness: ask for often according to the discrete point that step 3 processes on the tread contour line obtained Individual moment wheel rim is high, wheel rim is thick, and to its, wheel rim thickness high as this wheel rim of averaging；

Step 6, match point space-time reduces: the wheel rim apex coordinate that obtains the most in the same time is rotated by coordinate and time space-variant Change in the wheel rim apex circle being fused to synchronization；

Step 7, least square fitting circle: one group of wheel rim apex coordinate after conversion is passed through least square fitting Becoming a circle to solve wheel rim apex circle diameter, this diameter deducts the wheel rim height of twice and is the diameter of this wheel.

A kind of municipal rail train wheelset profile on-line measuring device, opens with the second laser-correlation including the first laser-correlation switch Closing and two groups of laser displacement sensors, two of which laser-correlation switch is by discharger and receives device composition, and two are swashed The discharger of light correlation switch is mounted on the same side of same track, and the reception device of two laser-correlation switches is respectively mounted Opposite side in this track；Two laser-correlation switches are mounted on support, at the bottom of track with two groups of laser displacement sensors The fixture in portion is fixed；First laser-correlation switch is installed on same with the second laser-correlation switch successively along train direction of advance The both sides of track, and the first laser-correlation switch is parallel with the second laser-correlation switch, mounting distance between the two is L₁；Two Group laser displacement sensor becomes symmetric mode to be installed on same track both sides, and train sequentially passes through the first laser along direction of advance Correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch is installed with laser displacement sensor Distance is L₂；With the Relative vertical distance respectively L of inner side laser displacement sensor and track outside track₃、L₄, outside track It is respectively β with the angle of inner side laser displacement sensor Yu plumb line₁、β₂, with inner side laser displacement sensor and edge outside track The vertical equity wire clamp angle of orbital direction is respectively α₁、α₂。

Compared with prior art, its remarkable advantage is the present invention: (1) low cost, it is only necessary to two groups of laser displacement sensors The detection of the wheelset profiles such as, wheel rim thickness high to wheel rim and wheel footpath can be realized；(2) wheel is automatically obtained by laser displacement sensor By continuous output coordinate during detecting system, processed by respective algorithms, it is thus achieved that the relevant wheelset profile of institute's measuring car wheel, operation Simply；(3) there is the advantages such as on line non contact measurement, provide a kind of effective solution for realizing wheelset profile on-line measurement Scheme.

Accompanying drawing explanation

Fig. 1 is the algorithm flow chart of the online acquisition methods of wheelset profile in the present invention.

Fig. 2 is the implantation of device figure of wheelset profile on-line measuring device in the present invention.

Fig. 3 is the sensor scheme of installation of wheel tread detection in the present invention.

Fig. 4 is the wheel rim summit schematic diagram detected the most in the same time.

Fig. 5 is the tread data point after coordinate transform, data fusion.

Detailed description of the invention

The present invention is based on laser sensor detecting system, by laser displacement sensor draw the most in the same time wheel rim high, Wheel rim thickness and the apex coordinate of wheel rim.Merged by the change commanders difference of wheel rim the most in the same time of the timely space-variant of space coordinate transformation In a coordinate system.These differences are become circle by least square fitting and draws wheel diameter.

Below in conjunction with the accompanying drawings and the present invention is described in further detail by specific embodiment.

In conjunction with Fig. 1, the acquisition methods of municipal rail train wheel tread contour line of the present invention and device, comprise the following steps:

Step 1, lays sensor: the first laser-correlation switch switchs along train direction of advance successively with the second laser-correlation It is installed on the both sides of same track, and the first laser-correlation switch is parallel with the second laser-correlation switch, peace between the two Dress distance is L₁；Two groups of laser displacement sensors become symmetric mode to be installed on same track both sides, and train depends on along direction of advance Secondary through the first laser-correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch and laser Displacement transducer mounting distance is L₂；Outside track, the Relative vertical distance with inner side laser displacement sensor with track is respectively L₃、L₄, outside track, the angle with inner side laser displacement sensor Yu plumb line is respectively β₁、β₂, with inner side laser outside track Displacement transducer is respectively α with the vertical equity wire clamp angle of direction along ng a path₁、α₂；

Step 2, packet: after two groups of laser displacement sensors sensing point coordinate of detecting wheel output simultaneously, by data Data point is grouped in the array of synchronization by the difference pressing output time；Detecting wheel output sensing point coordinate is to swash Light emission direction is y-axis, and being perpendicular to Laser emission direction is x-axis, and lasing light emitter is zero.

Step 3, coordinate transform, data fusion: two groups of laser displacement sensors are same by coordinate transform and coordinate translation The output point in one moment is fused on the same coordinate system, and the point after fusion is the discrete point on tread contour line；Sensor number According to obtaining and data fusion, specific as follows:

To the two-dimensional coordinate value (x of 2D laser displacement sensor output outside track_n ⁽¹⁾,y_n ⁽¹⁾) carry out according to below equation Coordinate transform (u_n ⁽¹⁾,v_n ⁽¹⁾):

${u_n}^{\left(1\right)}=\sqrt{{x_n}^{{\left(1\right)}^2}+{y_n}^{{\left(1\right)}^2}}\sin (\mathrm{\θ}+{\mathrm{\β}}_1)={x_n}^{\left(1\right)}\cos {\mathrm{\β}}_1+{y_n}^{\left(1\right)}\sin {\mathrm{\β}}_1$

${v_n}^{\left(1\right)}=\sqrt{{x_n}^{{\left(1\right)}^2}+{y_n}^{{\left(1\right)}^2}}\cos (\mathrm{\θ}+{\mathrm{\β}}_1)={y_n}^{\left(1\right)}\cos {\mathrm{\β}}_1-{x_n}^{\left(1\right)}\sin {\mathrm{\β}}_1$

To the two-dimensional coordinate value (x of 2D laser displacement sensor output inside track_n ⁽²⁾,y_n ⁽²⁾) carry out according to below equation Coordinate transform (u_n ⁽²⁾,v_n ⁽²⁾):

${u_n}^{\left(2\right)}=\sqrt{{x_n}^{{\left(2\right)}^2}+{y_n}^{{\left(2\right)}^2}}\sin ({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_2)={x_n}^{\left(2\right)}\cos {\mathrm{\β}}_2-{y_n}^{\left(2\right)}\sin {\mathrm{\β}}_2$

${u_n}^{\left(2\right)}=\sqrt{{x_n}^{{\left(2\right)}^2}+{y_n}^{{\left(2\right)}^2}}\sin ({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_2)={y_n}^{\left(2\right)}\cos {\mathrm{\β}}_2-{x_n}^{\left(2\right)}\sin {\mathrm{\β}}_2$

Wherein, θ is (x_n ⁽¹⁾,y_n ⁽¹⁾) with the angle of original coordinate system vertical coordinate, θ ' be (x_n ⁽²⁾,y_n ⁽²⁾) and original coordinates It is the angle of vertical coordinate, β₁For outer sensors and the angle of plumb line, β₂For the angle of inner sensors Yu plumb line, (u_n ⁽¹⁾,v_n ⁽¹⁾)、(u_n ⁽²⁾,v_n ⁽²⁾) it is the coordinate figure in coordinate system after original coordinates converts；

According to below equation, two groups of data after coordinate transform are merged:

u_n ⁽⁰⁾=u_n ⁽¹⁾+a u_n ⁽⁰⁾=u_n ⁽²⁾

v_n ⁽⁰⁾=v_n ⁽¹⁾+b v_n ⁽⁰⁾=v_n ⁽²⁾

Wherein (a, b) be outer sensors original coordinates initial point inner sensors convert after coordinate system in coordinate Value, (u_n ⁽⁰⁾,v_n ⁽⁰⁾) it is these 2 coordinate figures in merging coordinate system.

Step 4, extracts wheel rim apex coordinate: after merging, the discrete point on synchronization tread contour line is according to coordinate figure Size extract the coordinate points that ordinate value is minimum, this point coordinates is this moment wheel rim apex coordinate；

Step 5, obtains wheel rim height, wheel rim thickness: ask for often according to the discrete point that step 3 processes on the tread contour line obtained Individual moment wheel rim is high, wheel rim is thick, and to its, wheel rim thickness high as this wheel rim of averaging；

Step 6, match point space-time reduces: the wheel rim apex coordinate that obtains the most in the same time is rotated by coordinate and time space-variant Change in the wheel rim apex circle being fused to synchronization；Described match point space-time reduces, and detailed process is as follows:

(6.1) t is set₁、t₂、…、t_nFor wheel n moment in 2D laser sensor effective scope of detection, a₁、 a₂、…、a_i、…、a_nFor the wheel rim vertex position extracted in corresponding time step 4, and set a₁、a₂、…、a_i、…、a_nCoordinate is respectively For (x₁,y₁)、(x₂,y₂)、…、(x_i,y_i)、…(x_n,y_n)；

(6.2) vertical coordinate that n is put is carried out coordinate rotation, then coordinate rotates such as following formula:

y′_i=y_iCos (90 ° of-α)=y_i·sinα

In formula, α is sensor and horizontal setting angle；

(6.3) abscissa that n is put is carried out space-time reduction, it is assumed that a₁Coordinate be (0, y₁), then coordinate transform formula is such as Following formula:

x′_i=v (t_i-t₁)-|y₁-y_i|·cotα

X ' in formula_iFor t_iTime wheel rim summit through space-time reduce after abscissa, v is determined by following formula:

$v=\frac{L_1}{T_1-T_2}$

L in formula₁It is the mounting distance of two laser-correlation switches, T₁、T₂Be respectively wheel by first laser-correlation switch with The moment of switching signal is triggered during the second laser-correlation switch；

The point a ' in synchronization wheel rim apex circle after can drawing coordinate transform with up conversion₁、a′₂、…、a′_i、…、 a′_nCoordinate figure is (x '₁,y′₁), (x '₂,y′₂)、…、(x′_i,y′_i)…、(x′_n,y′_n)。

Step 7, least square fitting circle: one group of wheel rim apex coordinate after conversion is passed through least square fitting Becoming a circle to solve wheel rim apex circle diameter, this diameter deducts the wheel rim height of twice and is the diameter of this wheel.Least square Method fits to justify and draw wheel diameter, and detailed process is as follows:

Point coordinates (x ' is measured according in wheel rim apex circle n_i,y′_i) it is fitted circle, use method of least square, formula is such as Under:

$D=\sqrt{a^2+b^2+4\frac{\mathrm{\Σ}(x_i^{\′2}+x_i^{\′2})+\mathrm{a\Σ}{x}_i^{\′}+\mathrm{b\Σ}{y}_i^{\′}}{n}},i=\mathrm{1,2}...n$

In formula, a is the center of circle abscissa x after matching₀-2 times i.e. a=-2x₀, b is the center of circle vertical coordinate y after matching₀- 2 times i.e. b=-2y₀, and

$a=\frac{\mathrm{HD}-\mathrm{EG}}{\mathrm{CG}-D^2}$

$b=\frac{\mathrm{HC}-\mathrm{ED}}{D^2-\mathrm{GC}}$

In formula, C, D, E, G, H are intermediate parameters, as follows:

$\left.\begin{array}{c}C=\mathrm{n\Σ}{x}_i^{\′2}-\mathrm{\Σ}{x}_i^{\′}\mathrm{\Σ}{x}_i^{\′}\\ D=\mathrm{n\Σ}{x}_i^{\′}{y}_i^{\′}-\mathrm{\Σ}{x}_i^{\′}\mathrm{\Σ}{y}_i^{\′}\\ E=\mathrm{n\Σ}{x}_i^{\′3}+\mathrm{n\Σ}{x}_i^{\′}{y}_i^{\′2}-\mathrm{\Σ}(x_i^{\′2}+y_i^{\′2})\mathrm{\Σ}{x}_i^{\′}\\ G=\mathrm{n\Σ}{y}_i^{\′2}-\mathrm{\Σ}{y}_i^{\′}\mathrm{\Σ}{y}_i^{\′}\\ H=\mathrm{n\Σ}{x}_i^{\′2}{y}_i^{\′}+\mathrm{n\Σ}{y}_i^{\′3}-\mathrm{\Σ}(x_i^{\′2}+y_i^{\′2})\mathrm{\Σ}{y}_i^{\′}\end{array}\right\}i=\mathrm{1,2}...n$

The wheel rim height that the diameter solved deducts twice is the diameter of wheel.

In conjunction with Fig. 2～4, municipal rail train wheelset profile on-line measuring device of the present invention, including the first laser-correlation switch with Second laser-correlation switch and two groups of laser displacement sensors, two of which laser-correlation switch is by discharger and receives dress Putting composition, the discharger of two laser-correlation switches is mounted on the same side of same track, two laser-correlation switches Receive device and be mounted on the opposite side of this track；Two laser-correlation switches are mounted on propping up with two groups of laser displacement sensors On frame, fix the fixture of rail base；First laser-correlation switch depends on along train direction of advance with the second laser-correlation switch The secondary both sides being installed on same track, and the first laser-correlation switch is parallel, between the two with the second laser-correlation switch Mounting distance is L₁；Two groups of laser displacement sensors become symmetric mode to be installed on same track both sides, and train is along direction of advance Sequentially passing through the first laser-correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch is with sharp Optical displacement sensor mounting distance is L₂；Outside track, the Relative vertical distance with inner side laser displacement sensor with track is distinguished For L₃、L₄, outside track, the angle with inner side laser displacement sensor Yu plumb line is respectively β₁、β₂, swash with inner side outside track Optical displacement sensor is respectively α with the vertical equity wire clamp angle of direction along ng a path₁、α₂。

Described laser displacement sensor uses 2D laser displacement sensor based on principle of triangulation.Described first swashs It is mounted opposite distance L between light correlation switch and the second laser-correlation switch₁In the range of 100mm～400mm, and with track Relative vertical distance is in the range of 100mm～450mm, and the second laser-correlation switchs and laser displacement sensor mounting distance L₂For In the range of 0mm～100mm, with Relative vertical distance L of inner side laser displacement sensor Yu track outside track₃、L₄Scope equal For 100mm～450mm, with the angle β of inner side laser displacement sensor Yu plumb line outside track₁、β₂Scope be 25 °～ 65 °, with the vertical equity line angle α of inner side laser displacement sensor Yu direction along ng a path outside track₁、α₂Scope be 15 ° ～65 °.

Below in conjunction with specific embodiment, the present invention is described in further detail.

Embodiment 1

In conjunction with Fig. 2～4, two laser-correlation switches are mounted side by side along track both sides, and mounting distance between the two is L₁ For 200mm.Two groups of laser displacement sensors are installed on track both sides, then β with plumb line angle at 45 °₁、β₂It it is 45 °, and along track The vertical equity line angle at 45 ° in direction is installed, then α₁、α₂Being 45 °, the sampling interval of laser sensor is 33ms.

First the triggered time difference recording laser-correlation switch 1 and laser-correlation switch 1 is 132ms, and will detect Data point be the most temporally grouped, wheel pass through detecting system, sensor exports 6 groups of (t altogether₁, t₂..., t₆) valid data, Sensing point coordinate figure in each moment is carried out as the following formula coordinate transform:

u_n ⁽¹⁾==x_n ⁽¹⁾cos45°+y_n ⁽¹⁾sin45° u_n ⁽²⁾==x_n ⁽²⁾cos45°-y_n ⁽²⁾sin45°

v_n ⁽¹⁾==y_n ⁽¹⁾cos45°-x_n ⁽¹⁾sin45° v_n ⁽²⁾=y_n ⁽²⁾cos45°+x_n ⁽²⁾sin45°

Fig. 5 is wherein t₄Fusion after tread data point, according to merge after tread data point and tread profile geometry It is thick that relation calculates the wheel rim height collection wheel rim after each time data merges, and result is as shown in the table:

After merging, the discrete point on synchronization tread contour line extracts ordinate value according to the size of coordinate figure Little coordinate points, this point coordinates is this moment wheel rim apex coordinate, and result is as shown in the table:

The vertical coordinate extracted is carried out Rotating Transition of Coordinate:

y′_i=y_i·sin45°

The abscissa of 6 points is carried out space-time reduction, in conjunction with Fig. 4, it is assumed that a₁Coordinate be (0, y₁), then coordinate transform is public Formula such as following formula:

x′_i=v (t_i-t₁)-|y₁-y_i|·cot45°

Wherein t₁=0ms, t_i=(i-1) × 33ms.Triggered time T according to laser-correlation switch₁, T₂And two laser pair Penetrate the mounting distance L of switch₁, can obtain speed v is:

V=200/132=1.515m/s

Then the abscissa of these 6 points is:

Thus, by least square fitting circle, the coordinate of 6 points can be tried to achieve diameter D is 849.88mm, then wheel is straight Footpath is:

D_final=D-2 × 27.75=794.38mm

Therefore the wheel rim thickness of this wheel is 28.13mm, a height of 27.75mm of wheel rim, and wheel footpath is 794.38mm, surveys according to artificial The actual wheel rim thickness measuring this wheel is 28.2mm, a height of 27.9mm of wheel rim, and wheel footpath is 794.5mm, it is seen that the method meets scene Actual measurement requirement.

Claims (8)

1. a municipal rail train wheelset profile online test method, it is characterised in that comprise the following steps:

Step 1, lays sensor: the first laser-correlation switch is installed along train direction of advance successively with the second laser-correlation switch In the both sides of same track, and the first laser-correlation switch is parallel with the second laser-correlation switch, locating distance between the two From for L₁；Two groups of laser displacement sensors become symmetric mode to be installed on same track both sides, and train is along direction of advance successively warp Cross the first laser-correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch and laser displacement Sensor mounting distance is L₂；With the Relative vertical distance respectively L of inner side laser displacement sensor and track outside track₃、 L₄, outside track, the angle with inner side laser displacement sensor Yu plumb line is respectively β₁、β₂, with laser position, inner side outside track Displacement sensor is respectively α with the vertical equity wire clamp angle of direction along ng a path₁、α₂；

Step 2, packet: after two groups of laser displacement sensors sensing point coordinate of detecting wheel output simultaneously, data point is pressed Data point is grouped in the array of synchronization by the difference of output time；

Step 3, coordinate transform, data fusion: by coordinate transform and coordinate translation by two groups of laser displacement sensors with for the moment The output point carved is fused on the same coordinate system, and the point after fusion is the discrete point on tread contour line；

Step 4, extracts wheel rim apex coordinate: big according to coordinate figure of the discrete point on synchronization tread contour line after merging The little coordinate points extracting ordinate value minimum, this point coordinates is this moment wheel rim apex coordinate；

Step 5, obtains wheel rim height, wheel rim thickness: when asking for each according to the discrete point on the tread contour line that step 3 process obtains Carve wheel rim height, wheel rim thickness, and to its, wheel rim thickness high as this wheel rim of averaging；

Step 6, match point space-time reduces: rotated by coordinate by the wheel rim apex coordinate obtained the most in the same time and space-time transformation is melted Close in the wheel rim apex circle of synchronization；

Step 7, least square fitting circle: one group of wheel rim apex coordinate after conversion is become by least square fitting Individual circle solves wheel rim apex circle diameter, and this diameter deducts the wheel rim height of twice and is the diameter of this wheel.

Municipal rail train wheelset profile online test method the most according to claim 1, it is characterised in that described in step 1 Laser displacement sensor uses 2D laser displacement sensor based on principle of triangulation.

Municipal rail train wheelset profile online test method the most according to claim 1, it is characterised in that described in step 2 Detecting wheel output sensing point coordinate is with Laser emission direction as y-axis, and being perpendicular to Laser emission direction is x-axis, and lasing light emitter is Zero.

Municipal rail train wheelset profile online test method the most according to claim 1, it is characterised in that sit described in step 3 Mark conversion, the specifically comprising the following steps that of data fusion

To the two-dimensional coordinate value (x of laser displacement sensor output outside track_n ⁽¹⁾,y_n ⁽¹⁾) carry out coordinate change according to below equation Change (u_n ⁽¹⁾,v_n ⁽¹⁾):

${u_n}^{\left(1\right)}=\sqrt{{x_n}^{{\left(1\right)}^2}+{y_n}^{{\left(1\right)}^2}}sin(\mathrm{\θ}+{\mathrm{\β}}_1)={x_n}^{\left(1\right)}{\mathrm{cos\β}}_1+{y_n}^{\left(1\right)}{\mathrm{sin\β}}_1$

${v_n}^{\left(1\right)}=\sqrt{{x_n}^{{\left(1\right)}^2}+{y_n}^{{\left(1\right)}^2}}\cos (\mathrm{\θ}+{\mathrm{\β}}_1)={y_n}^{\left(1\right)}{\mathrm{cos\β}}_1-{x_n}^{\left(1\right)}{\mathrm{sin\β}}_1$

To the two-dimensional coordinate value (x of laser displacement sensor output inside track_n ⁽²⁾,y_n ⁽²⁾) carry out coordinate change according to below equation Change (u_n ⁽²⁾,v_n ⁽²⁾):

${u_n}^{\left(2\right)}=\sqrt{{x_n}^{{\left(2\right)}^2}+{y_n}^{{\left(2\right)}^2}}sin({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_2)={x_n}^{\left(2\right)}{\mathrm{cos\β}}_2-{y_n}^{\left(2\right)}{\mathrm{sin\β}}_2$

${v_n}^{\left(2\right)}=\sqrt{{x_n}^{{\left(2\right)}^2}+{y_n}^{{\left(2\right)}^2}}\cos ({\mathrm{\θ}}^{\′}-{\mathrm{\β}}_2)={y_n}^{\left(2\right)}{\mathrm{cos\β}}_2+{x_n}^{\left(2\right)}{\mathrm{sin\β}}_2$

Wherein, θ is (x_n ⁽¹⁾,y_n ⁽¹⁾) with the angle of original coordinate system vertical coordinate, θ ' be (x_n ⁽²⁾,y_n ⁽²⁾) seat vertical with original coordinate system Target angle, β₁For outer sensors and the angle of plumb line, β₂For the angle of inner sensors Yu plumb line, (u_n ⁽¹⁾,v_n ⁽¹⁾)、(u_n ⁽²⁾,v_n ⁽²⁾) it is the coordinate figure in coordinate system after original coordinates converts；

According to below equation, two groups of data after coordinate transform are merged:

u_n ⁽⁰⁾=u_n ⁽¹⁾+a u_n ⁽⁰⁾=u_n ⁽²⁾

v_n ⁽⁰⁾=v_n ⁽¹⁾+b v_n ⁽⁰⁾=v_n ⁽²⁾

Wherein (a, b) be outer sensors original coordinates initial point inner sensors convert after coordinate system in coordinate figure, (u_n ⁽⁰⁾,v_n ⁽⁰⁾) it is these 2 coordinate figures in merging coordinate system.

Municipal rail train wheelset profile online test method the most according to claim 1, it is characterised in that described in step 6 Match point space-time reduces, and detailed process is as follows:

(6.1) t is set₁、t₂、…、t_nFor wheel n moment in 2D laser sensor effective scope of detection, a₁、a₂、…、 a_i、…、a_nFor the wheel rim vertex position extracted in corresponding time step 4, and set a₁、a₂、…、a_i、…、a_nCoordinate is respectively (x₁, y₁)、(x₂,y₂)、…、(x_i,y_i)、…(x_n,y_n)；

(6.2) vertical coordinate that n is put is carried out coordinate rotation, then coordinate rotates such as following formula:

y′_i=y_iCos (90 ° of-α)=y_i·sinα

In formula, α is sensor and horizontal setting angle；

(6.3) abscissa that n is put is carried out space-time reduction, it is assumed that a₁Coordinate be (0, y₁), then coordinate transform formula is as follows Formula:

x′_i=v (t_i-t₁)-|y₁-y_i|·cotα

X ' in formula_iFor t_iTime wheel rim summit through space-time reduce after abscissa, v is determined by following formula:

$v=\frac{L_1}{T_1-T_2}$

L in formula₁It is the mounting distance of two laser-correlation switches, T₁、T₂It is respectively wheel by the first laser-correlation switch with second The moment of switching signal is triggered during laser-correlation switch；

The point a ' in synchronization wheel rim apex circle after can drawing coordinate transform with up conversion₁、a′₂、…、a′_i、…、a′_nCoordinate Value is (x '₁,y′₁), (x '₂,y′₂)、…、(x′_i,y′_i)…、(x′_n,y′_n)。

Municipal rail train wheelset profile online test method the most according to claim 1, it is characterised in that described in step 7 Least square fitting becomes circle and draws wheel diameter, and detailed process is as follows:

Point coordinates (x ' is measured according in wheel rim apex circle n_i,y′_i) it is fitted circle, use method of least square, formula is as follows:

$D=\sqrt{a^2+b^2+4\frac{\mathrm{\Σ}(x_i^{\′2}+y_i^{\′2})+{\mathrm{a\Σx}}_i^{\′}+{\mathrm{b\Σy}}_i^{\′}}{n}},i=1,2...n$

In formula, a is the center of circle abscissa x after matching₀-2 times i.e. a=-2x₀, b is the center of circle vertical coordinate y after matching₀-2 times I.e. b=-2y₀, and

$a=\frac{HD-EG}{CG-D^2}$

$b=\frac{HC-ED}{D^2-GC}$

In formula, C, D, E, G, H are intermediate parameters, as follows:

$\left.\begin{array}{c}C={\mathrm{n\Σx}}_i^{\′2}-{\mathrm{\Σx}}_i^{\′}{\mathrm{\Σx}}_i^{\′}\\ D={\mathrm{n\Σx}}_i^{\′}{y}_i^{\′}-{\mathrm{\Σx}}_i^{\′}{\mathrm{\Σy}}_i^{\′}\\ E={\mathrm{n\Σx}}_i^{\′3}+{\mathrm{n\Σx}}_i^{\′}{y}_i^{\′2}-\mathrm{\Σ}\left(x_i^{\′2}+y_i^{\′2}\right){\mathrm{\Σx}}_i^{\′}\\ G={\mathrm{n\Σy}}_i^{\′2}-{\mathrm{\Σy}}_i^{\′}{\mathrm{\Σy}}_i^{\′}\\ H={\mathrm{n\Σx}}_i^{\′2}{y}_i^{\′}+{\mathrm{n\Σy}}_i^{\′3}-\mathrm{\Σ}\left(x_i^{\′2}+y_i^{\′2}\right){\mathrm{\Σy}}_i^{\′}\end{array}\right\},i=1,2...n$

The wheel rim height that the diameter solved deducts twice is the diameter of wheel.

7. a municipal rail train wheelset profile on-line measuring device, including two groups of laser displacement sensors, two groups of laser displacements pass Sensor is mounted on support, the fixture of rail base fix, and two groups of laser displacement sensors become symmetric mode to be installed on together Article one, track both sides, with the Relative vertical distance respectively L of inner side laser displacement sensor and track outside track₃、L₄, track Outside is respectively β with the angle of inner side laser displacement sensor with plumb line₁、β₂, with inner side laser displacement sensor outside track It is respectively α with the vertical equity wire clamp angle of direction along ng a path₁、α₂, it is characterised in that also include that the first laser-correlation switch is with the Dual-laser correlation switchs, and two of which laser-correlation switch is by discharger and receives device composition, and two laser-correlations are opened The discharger closed is mounted on the same side of same track, and the reception device of two laser-correlation switches is mounted on this track Opposite side；Two laser-correlation switches are mounted on support, the fixture of rail base fix；First laser-correlation switch The both sides being installed on same track along train direction of advance successively, and the first laser-correlation switch is switched with the second laser-correlation Parallel with the second laser-correlation switch, mounting distance between the two is L₁；Train sequentially passes through the first laser along direction of advance Correlation switch, the second laser-correlation switch, laser displacement sensor, the second laser-correlation switch is installed with laser displacement sensor Distance is L₂。

Municipal rail train wheelset profile on-line measuring device the most according to claim 7, it is characterised in that described first laser It is mounted opposite distance L between correlation switch and the second laser-correlation switch₁In the range of 100mm～400mm, and with the phase of track To vertical dimension in the range of 100mm～450mm, the second laser-correlation switch and laser displacement sensor mounting distance L₂For In the range of 0mm～100mm, with Relative vertical distance L of inner side laser displacement sensor Yu track outside track₃、L₄Scope equal For 100mm～450mm, with the angle β of inner side laser displacement sensor Yu plumb line outside track₁、β₂Scope be 25 °～ 65 °, with the vertical equity line angle α of inner side laser displacement sensor Yu direction along ng a path outside track₁、α₂Scope be 15 ° ～65 °.