CN104590314A - Device and method for measuring diameter of urban rail vehicle wheel based on multiple sensors - Google Patents

Abstract

The invention discloses a device and a method for measuring diameter of an urban rail vehicle wheel based on multiple sensors. The measuring device consists of a laser displacement sensor, a speed measuring sensor and a vortex sensor which are arranged along the direction of a steel rail, wherein the speed measuring sensor is used for detecting the speed of the wheel passing through a wheel diameter measuring device, the vortex sensor is used for positioning a wheel center to the part just above the sensor, the laser displacement sensor is used for measuring the distance between a wheel pedal surface and the laser sensor, a two-dimensional right-angle coordinate system is established to perform time and space reduction on the output points of the laser sensor at different times into a wheel circle, the diameter of the wheel is calculated by the reduction points at different times and the positioning point of the vortex sensor, and finally the diameter at different time is subject to error filtering and equalizing, so as to obtain the final diameter of the wheel. The device has the advantages that the online non-contact type measuring is realized; the speed is high, the accuracy is high, the structure is simple, and the like.

Description

A kind of wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors and method

Technical field

The present invention relates to rolling stock detection technique field, particularly a kind of wheel diameter of urban rail vehicle detecting device based on multiple sensors and method.

Background technology

In city rail traffic system, wheel is the important step affecting safe operation, particularly after train speed-raising, requires higher to the profile physical dimension of wheel.Taking turns device is ensure the operation of rolling stock on rail and turn to, and bearing whole quiet, the live load from rolling stock, is extremely important parts in locomotive walking structure.The defect such as wearing and tearing, scratch, stripping, crackle on wheel tread surface and nearly surface is the big factors jeopardizing traffic safety.Owing to running under high speed, refitting, conditions of high density, the wearing and tearing of train wheel are more and more serious, greatly affect safety and the service life of locomotive and orbital facilities.Therefore, train wheel uses state great on transportation safety impact, often carries out detection to train wheel important parameter and seems very necessary.

Whether run by train, the domestic and international measurement for rail wheels geometric parameters at present mainly contains Static Detection and detection of dynamic.Static Detection is carried out at vehicle non-operating state, although the method precision is higher, detection efficiency is very low.Detection of dynamic is carried out under the running state of vehicle, and be characterized in that accuracy of detection is high, detection speed fast, it is high to detect degree of automation, and do not take car cycle, just implement more difficult, technical risk is higher.

Early stage domestic general employing is measured based on CCD measurement image measurement technique, but the method exists system architecture complicated layout, and poor anti jamming capability.Along with the development of sensor technology, laser displacement sensor is more and more extensive to the application on diameter measurement at wheel.In wheel diameter measurement process, how technical barrier makes measurement mechanism as far as possible simple, survey precision and measurement speed of response improves.

Summary of the invention

The object of the present invention is to provide high, the fireballing wheel diameter of urban rail vehicle detecting device based on multiple sensors of a kind of survey precision and method, adopt non-contact measurement, cost is low, be easy to operation.

The technical solution realizing the object of the invention is: a kind of wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors, along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors to be all fixed on track and to be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α.

Based on a wheel diameter of urban rail vehicle method of measurement for multiple sensors, step is as follows:

Step 1, sensor is set: along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors are on same straight line and be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α, works as L ₂when being less than 100mm, wheel is the speed that speed sensor records by the speed of checking system;

Step 2, sets up two-dimensional coordinate system: set up two-dimensional coordinate system in the plane at the wheel circumference carrying out diameter measurement, and with laser displacement sensor position for origin, wheel working direction is x-axis negative direction, and direction is straight up y-axis positive dirction;

Step 3, the output valve of measurement of vehicle speed v and laser displacement sensor: record t ₁the output l of moment laser displacement sensor ₁, and record the probe value v of tachogenerator; When wheel continues to move forward, laser displacement sensor has continuously distance value l _iexport, i=1,2,3,4

Step 4, coordinate points space-time reduces: carry out space-time reduction to the coordinate on each moment wheel rim summit that laser displacement sensor effectively exports, and incites somebody to action not coordinate points in the same time and is reduced to t ₁time to be engraved on wheel residing position, and obtain the coordinate of this point in step 2 in built system of axes;

Step 5, asks for each moment wheel diameter: show that coordinate a little calculates each moment wheel diameter according to eddy current sensor locating point and step 4;

Step 6, ask for final wheel diameter: adopt 1.5 σ criterions to remove gross error to the diameter value in each moment that step 5 is tried to achieve, adopt linear function to carry out least square fitting on a timeline to residual diameter value and draw fit equation, calculate the ordinate value of not fit equation in the same time, and carry out equalization process, thus obtain final wheel diameter.

Compared with prior art, its remarkable advantage is in the present invention: (1) is based on multiple sensors and adopt non-contact measurement, achieves the online high-acruracy survey to train; (2) automatically obtain wheel points coordinate by laser sensor, tachogenerator records vehicle gait of march automatically, and by respective algorithms processing data, obtains institute's measuring car wheel diameter instantly, and method is simple, be easy to operation; (3) there is the advantage that detection speed is fast, cost is low.

Accompanying drawing explanation

Fig. 1 is the diagram of circuit of the wheel diameter of urban rail vehicle method of measurement that the present invention is based on multiple sensors.

Fig. 2 is the sensor scheme of installation of the wheel diameter of urban rail vehicle measurement mechanism that the present invention is based on multiple sensors.

Fig. 3 is the wheel rim summit schematic diagram do not detected in the same time in the present invention.

Fig. 4 is diameter value distributed points and the fitting a straight line figure thereof of different significant instant in the present invention.

Detailed description of the invention

Below in conjunction with drawings and the specific embodiments, the present invention is described in further detail.

Composition graphs 1 ~ 3, the present invention is based on the wheel diameter of urban rail vehicle measurement mechanism of multiple sensors, along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors to be all fixed on track and to be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α.

Between the Laser emission direction of described laser displacement sensor and track, the scope of angle α is 15 ~ 65 °, and the sampling interval of laser displacement sensor is 25 ~ 40ms.

Distance L between described tachogenerator and eddy current sensor ₂be 10 ~ 100mm, particularly 450mm; Distance L between laser displacement sensor and eddy current sensor ₁be 440 ~ 460mm, particularly 80mm; Now wheel is the speed that tachogenerator records by the speed of checking system.

As shown in Figure 1, the present invention is based on the wheel diameter of urban rail vehicle method of measurement of multiple sensors, step is as follows:

Step 1, sensor is set: composition graphs 2, along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors are on same straight line and be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α, works as L ₂when being less than 100mm, wheel is the speed that speed sensor records by the speed of checking system; Described laser displacement sensor adopts the laser displacement sensor based on principle of triangulation, and laser displacement sensor is for measuring the distance between wheel tread basic point and laser displacement sensor.

Step 2, sets up two-dimensional coordinate system: set up two-dimensional coordinate system in the plane at the wheel circumference carrying out diameter measurement, and with laser displacement sensor position for origin, wheel working direction is x-axis negative direction, and direction is straight up y-axis positive dirction;

Step 3, the output valve of measurement of vehicle speed v and laser displacement sensor: record t ₁the output l of moment laser displacement sensor ₁, and record the probe value v of tachogenerator; When wheel continues to move forward, laser displacement sensor has continuously distance value l _iexport, i=1,2,3,4 Extract wherein t ₂the output valve l in moment ₂;

Step 4, coordinate points space-time reduces: carry out space-time reduction to the coordinate on each moment wheel rim summit that laser displacement sensor effectively exports, and incites somebody to action not coordinate points in the same time and is reduced to t ₁time to be engraved on wheel residing position, and obtain the coordinate of this point in step 2 in built system of axes; Concrete grammar is as follows:

(4.1) t is established ₁, t ₂..., t _i..., t _nfor n the moment of wheel in laser displacement sensor effective scope of detection, a ₁, a ₂..., a _i..., a _nfor the wheel rim vertex position extracted in corresponding time step 4, and establish a ₁, a ₂..., a _i..., a _ncoordinate after conversion is respectively (x ₁, y ₁), (x ₂, y ₂) ..., (x _i, y _i) ... (x _n, y _n);

(4.2) formula of coordinate transforming is as follows:

x _i＝l _i·cosα+vΔt _i

y _i＝l _i·sinα

In formula: v is the vehicle speed of advance that tachogenerator records; x _ifor the abscissa value after coordinate transforming; y _ifor the ordinate value after coordinate transforming; Δ t _ifor corresponding t _imoment and t ₁the time difference in moment:

Δt _i＝t _i-t ₁。

Step 5, asks for each moment wheel diameter: show that coordinate a little calculates each moment wheel diameter according to eddy current sensor locating point and step 4; Eddy current sensor is for the lowest point of positioning car wheel rim apex circle in vertical.Describedly ask for each moment wheel diameter, detailed process is as follows:

Get t successively ₁, t ₂..., t _i..., t _npoint (the x of moment after space-time reduction ₁, y ₁), (x ₂, y ₂) ..., (x _i, y _i) ... (x _n, y _n), and the distance L of eddy current sensor locating point and eddy current sensor and laser sensor ₁, ask for wheel diameter and draw a series of diameter value;

If central coordinate of circle is (L ₁, R), then have round equation as follows:

(L ₁-x _i) ²+(R-y _i) ²＝R ²

Arrange:

$R=\frac{{L_1}^2-{2L}_1{l}_i\cos \mathrm{\α}+{l_i}^2-{2L}_{1}v{\mathrm{\Δt}}_i\cos \mathrm{\α}+v^2{{\mathrm{\Δt}}_i}^2}{{2l}_i\sin \mathrm{\α}}$

D＝2R

In formula, R is the radius value of institute's measuring car wheel, and D is the diameter value of institute's measuring car wheel, L ₁for the mounting distance between eddy current sensor and laser sensor, α is the angle between laser rays and track, and v is train running speed, l _ifor the output valve of i moment laser displacement sensor, Δ t _ifor corresponding t _imoment and t ₁the time difference in moment.

Step 6, ask for final wheel diameter: adopt 1.5 σ criterions to remove gross error to the diameter value in each moment that step 5 is tried to achieve, adopt linear function to carry out least square fitting on a timeline to residual diameter value and draw fit equation, calculate the ordinate value of not fit equation in the same time, and carry out equalization process, thus obtain final wheel diameter.Concrete grammar is as follows:

(6.1) adopt 1.5 σ criterions to remove the gross error of this series of diameter value, formula is as follows:

$\left|V_b\right|=|D_i-\stackrel{\‾}{D}|>1.5\mathrm{\σ}$

In formula, V _bfor the residual error of bad value; D _ifor the diameter value adopting different moment point to obtain; it is the center line average values of the whole observed readings comprising bad value; σ is the standard deviation measuring row, replaces with estimated valve s;

Diameter value result of calculation being greater than 1.5 σ is all removed, and draws a series of diameter data after removing gross error;

(6.2) remaining diameter value after removal gross error is arranged in chronological order, with a straight line y=kt+b by least square fitting, and obtain fitting a straight line equation;

(6.3) after calculating removal gross error, excess time puts the ordinate value of corresponding fit equation, and averaged, represent wheel diameter with this, diameter formula is:

$D=\stackrel{\‾}{y}$

In formula: for the center line average values of the corresponding equation of straight line ordinate of some excess time after removal gross error.

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

Embodiment 1

Composition graphs 2, laser displacement sensor and track angle at 45 ° are installed on by track, then α is 45 °, and the sampling interval of laser displacement sensor is 20ms, the mounting distance L of laser displacement sensor and eddy current sensor ₁for 500mm, the mounting distance L of eddy current sensor and speed sensor ₂for 80mm.

First the observed reading recording speed sensor is 1.51m/s, and is temporally divided into groups by the distance value detected, and wheel is by checking system, and sensor exports 6 groups of (t altogether ₁, t ₂..., t ₆) valid data, as shown in the table.

The probe value in each moment is carried out space-time transformation by following formula:

x _i＝l _i·cosα+vΔt _i

y _i＝l _i·sinα

Coordinate after conversion is as shown in the table:

Each moment wheel diameter is asked for as shown in the table according to the coordinate after conversion:

Adopted by each moment diameter value of trying to achieve 1.5 σ criterions to remove gross error, can t be obtained ₃the diameter value in moment is gross error, the diameter value in other moment is carried out least square fitting, as shown in Figure 4.

Ask for the functional value of each significant instant according to the equation of straight line simulated, and do equalization process, obtaining final diameter is:

D＝838.4360mm

On-the-spot by manual measurement, the wheel rim apex circle diameter of this wheel is 838.6mm, and this system can meet on-the-spot Surveying Actual Precision requirement as can be seen here.

Claims (10)

1. the wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors, it is characterized in that, along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors to be all fixed on track and to be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α.

2. the wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors according to claim 1, it is characterized in that, between the Laser emission direction of described laser displacement sensor and track, the scope of angle α is 15 ~ 65 °, and the sampling interval of laser displacement sensor is 25 ~ 40ms.

3. the wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors according to claim 1, is characterized in that, the distance L between described tachogenerator and eddy current sensor ₂be 10 ~ 100mm, the distance L between laser displacement sensor and eddy current sensor ₁be 440 ~ 460mm, now wheel is the speed that tachogenerator records by the speed of checking system.

4. the wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors according to claim 3, is characterized in that, the distance L between described laser displacement sensor and eddy current sensor ₁for 450mm, the distance L between eddy current sensor and speed sensor ₂for 80mm.

5., based on a wheel diameter of urban rail vehicle method of measurement for multiple sensors, it is characterized in that, step is as follows:

Step 1, sensor is set: along vehicle forward direction, a tachogenerator, an eddy current sensor and a laser displacement sensor is set gradually outside track, three sensors are on same straight line and be parallel to track bearing of trend, and the distance wherein between tachogenerator and eddy current sensor is L ₂, the distance between eddy current sensor and laser displacement sensor is L ₁, the Laser emission direction of laser displacement sensor and the angle of train working direction are 180 ° of-α, and the angle namely between the Laser emission direction of laser displacement sensor and track is α, works as L ₂when being less than 100mm, wheel is the speed that speed sensor records by the speed of checking system;

Step 2, sets up two-dimensional coordinate system: set up two-dimensional coordinate system in the plane at the wheel circumference carrying out diameter measurement, and with laser displacement sensor position for origin, wheel working direction is x-axis negative direction, and direction is straight up y-axis positive dirction;

Step 3, the output valve of measurement of vehicle speed v and laser displacement sensor: record t ₁the output l of moment laser displacement sensor ₁, and record the probe value v of tachogenerator; When wheel continues to move forward, laser displacement sensor has continuously distance value l _iexport, i=1,2,3,4

Step 4, coordinate points space-time reduces: carry out space-time reduction to the coordinate on each moment wheel rim summit that laser displacement sensor effectively exports, and incites somebody to action not coordinate points in the same time and is reduced to t ₁time to be engraved on wheel residing position, and obtain the coordinate of this point in step 2 in built system of axes;

Step 5, asks for each moment wheel diameter: show that coordinate a little calculates each moment wheel diameter according to eddy current sensor locating point and step 4;

Step 6, ask for final wheel diameter: adopt 1.5 σ criterions to remove gross error to the diameter value in each moment that step 5 is tried to achieve, adopt linear function to carry out least square fitting on a timeline to residual diameter value and draw fit equation, calculate the ordinate value of not fit equation in the same time, and carry out equalization process, thus obtain final wheel diameter.

6. the wheel diameter of urban rail vehicle method of measurement based on multiple sensors according to claim 5, it is characterized in that, laser displacement sensor described in step 1 adopts the laser displacement sensor based on principle of triangulation, and laser displacement sensor is for measuring the distance between wheel tread basic point and laser displacement sensor.

7. the wheel diameter of urban rail vehicle method of measurement based on multiple sensors according to claim 5, is characterized in that, coordinate points space-time reduction described in step 4, and concrete grammar is as follows:

(4.1) t is established ₁, t ₂..., t _i..., t _nfor n the moment of wheel in laser displacement sensor effective scope of detection, a ₁, a ₂..., a _i..., a _nfor the wheel rim vertex position extracted in corresponding time step 4, and establish a ₁, a ₂..., a _i..., a _ncoordinate after conversion is respectively (x ₁, y ₁), (x ₂, y ₂) ..., (x _i, y _i) ... (x _n, y _n);

(4.2) formula of coordinate transforming is as follows:

x _i＝l _i·cosα+vΔt _i

y _i＝l _i·sinα

In formula: v is the vehicle speed of advance that tachogenerator records; x _ifor the abscissa value after coordinate transforming; y _ifor the ordinate value after coordinate transforming; Δ t _ifor corresponding t _imoment and t ₁the time difference in moment:

Δt _i＝t _i-t ₁。

8. the wheel diameter of urban rail vehicle method of measurement based on multiple sensors according to claim 5, is characterized in that, the eddy current sensor described in step 5 is for the lowest point of positioning car wheel rim apex circle in vertical.

9., according to a kind of wheel diameter of urban rail vehicle measurement mechanism based on multiple sensors shown in claim 1 and method, it is characterized in that, ask for each moment wheel diameter described in step 5, detailed process is as follows:

Get t successively ₁, t ₂..., t _i..., t _npoint (the x of moment after space-time reduction ₁, y ₁), (x ₂, y ₂) ..., (x _i, y _i) ... (x _n, y _n), and the distance L of eddy current sensor locating point and eddy current sensor and laser sensor ₁, ask for wheel diameter and draw a series of diameter value;

If central coordinate of circle is (L ₁, R), then have round equation as follows:

(L ₁-x _i) ²+(R-y _i) ²＝R ²

Arrange:

$R=\frac{{L_1}^2-2L_1{l}_i\cos \mathrm{\α}+{l_i}^2-2L_1\mathrm{v\Δ}{t}_i+2l_i\mathrm{v\Δ}{t}_i\cos \mathrm{\α}+v^2\mathrm{\Δ}{t_i}^2}{2l_i\sin \mathrm{\α}}$

D＝2R

In formula, R is the radius value of institute's measuring car wheel, and D is the diameter value of institute's measuring car wheel, L ₁for the mounting distance between eddy current sensor and laser sensor, α is the angle between laser rays and track, and v is train running speed, l _ifor the output valve of i moment laser displacement sensor, Δ t _ifor corresponding t _imoment and t ₁the time difference in moment.

10. the wheel diameter of urban rail vehicle method of measurement based on multiple sensors according to claim 5, it is characterized in that, it is characterized in that, ask for final wheel diameter described in step 6, concrete grammar is as follows:

(6.1) adopt 1.5 σ criterions to remove the gross error of this series of diameter value, formula is as follows:

$\left|V_b\right|=|D_i-\stackrel{\‾}{D}|>1.5\mathrm{\σ}$

In formula, V _bfor the residual error of bad value; D _ifor the diameter value adopting different moment point to obtain; it is the center line average values of the whole observed readings comprising bad value; σ is the standard deviation measuring row, replaces with estimated valve s;

Diameter value result of calculation being greater than 1.5 σ is all removed, and draws a series of diameter data after removing gross error;

(6.2) remaining diameter value after removal gross error is arranged in chronological order, with a straight line y=kt+b by least square fitting, and obtain fitting a straight line equation;

(6.3) after calculating removal gross error, excess time puts the ordinate value of corresponding fit equation, and averaged, represent wheel diameter with this, diameter formula is:

$D=\stackrel{\‾}{y}$

In formula: for the center line average values of the corresponding equation of straight line ordinate of some excess time after removal gross error.