# The correction method of the passed distance sensor

(57) Abstract:

The invention relates to the field of monitoring and forecasting the state of the railroad tracks. On the basis of the digital filter to produce integration changes the geographical coordinates and the velocity of the object, obtained by processing information received from a satellite navigation system and channels of navigation and orientation, and odometer. Next, get an updated assessment of the accuracy of the odometer, which adjust the nominal value of its step. Depending on the mode of motion of an object change the transfer function of the digital filter in accordance with the model of sensor errors sailed distance. The invention provides correction encoder, the error of which is not dependent on the mode and conditions of movement of the object. 3 C.p. f-crystals.

Use: for the control and forecast the state of the railroad tracks. The inventive method is that the measured changes in the geographical coordinates and the velocity of the object during the movement with the help of satellite navigation systems, as well as with the help of navigation and orientation, and odometer. Based on the obtained information, use the position of the object, is the integration (fusion) of these systems. The result of revised estimates of the error odometer, which adjust the nominal value of its step.

The invention relates to the control of the state Railways. The known method odometer correction for changes in geographic coordinates [1, 2], produced by the testimony of the satellite navigation system (SNS). At the same time as the system for measuring the angular position of the track relative to the horizon and course angle is used strapdown inertial navigation system and a position sensor (PSD) of the car body relative to the track.

At each i-th step (when developing the odometer signal) determine the increment of geographical coordinates with consideration of pitch angles_{i}and of course TO_{i}track

where l is the price of one division of the odometer. Further divided into intervals, each of which contains n odometer. The spacing (n) is chosen according to some criterion. In particular, since the signals odometer usually postoptimal SNA. The total increment of geographical coordinates on the k-th interval is found by summing:

SNA produces spherical geographic coordinates: geodetic latitude (the angle between the equator and the normal to the surface of the spheroid),geodetic longitude and altitude h above sea level (Referenz-ellipsoid). The relationship between geocentric coordinates and produced SNA coordinates, and h is determined by the ratios:

where e is the eccentricity of the ellipsoid, a and b are the semiaxes of the ellipsoid (ellipsoid of Hayford a=6378388 m; b=6356909 m).

Increment geocentric coordinates on the testimony of the SNA at the k-th interval, the corresponding calculated using formulas (1), determined with reference to (3)

They transformed the DER="0">

where A(_{k-1},_{k-1}) is the transition matrix of the geocentric coordinate system to geographic topocentric.

Errors, , measurement increment coordinate odometer are formed in accordance with the expression (1). Their constituents are systematic dl_{s}and random dl_{r}error odometer, as well as the systematic and random error d_{s}d_{r}, dK_{s}and dK_{r}measurements of the angles of pitch and of course the track. These angles are produced by the measuring range of the car, which includes beans. Error , and

where indicated dl=dl_{s}+dl_{r}, dK=dK_{s}+dK_{r}.

Thus, to assess the accuracy of the odometer, the state vector of the filter (for example, the optimal Kalman filter (OFC)) are in the form

where d’, d’, d’ - errors in the determination of the increments geographical coordinates according to the SNA;introduced in the state vector X, since d’, d’, d’ are described by differential equations of 2nd order.

Taking into account (5) the measurement equation, which can be the difference increments geographical coordinates determined by the odometer and SNA, prinimaya

Further develop assessment systematic dl_{s}and random dl_{r}error odometer, which is used for correction.

The known method odometer correction for changes geographical coordinates generated by the testimony of the satellite navigation system (SNS). At the same time as the system for measuring the angular position of the track relative to the horizon and course angle is used analytical girovertikal truncated composition (AGBUS) [3] and SDP body of the carriage relative to the track.

On the basis of measurements of increments of coordinates on the testimony of the SNA’_{k},’_{k},’_{k}(4) evaluate changes and course angle to the track and change the absolute value of the projection of the displacement vector measurement truck to the plane of the horizon L’_{k}for iteration

According to the odometer, AGUUS and get PSD estimate of the change course angleK_{k}and the increment of the horizontal component of the path

where i is the number of pulse odometer during the iteration; V_{i}the speed odometer; b_{i}- centripetal acceleration; n - number of pulses odometer, received during the iteration;_{P}- the current value of the longitudinal angle of slope of the track, produced by the testimony of AGUAS (_{i}and PSD, which determines the angle of the truck relative to the car body in its diametral plane (_{DP})

As elements of the vector of measurements OFC are the differences:

1) assessments of changes in the exchange rate is k(8);

2) projections of the vector of displacements on the axis AboutGSK_{k}(2) and’_{k}(4);

3) increments the horizontal components of the path(10) and(9)

The state vector in this case will be of the form

where dL_{ml}- accuracy determination of passed distance on the odometer; dW_{x}, dW_{y}, dW_{z}- errors in the readings of accelerometers included in AGUAS; dl_{DP1}dl_{DP}dl_{DP}dl_{DP}- errors in the readings of the position sensors PSD; d’_{r}d’_{r}d’_{r}- errors in the determination of changes of coordinates Catolica by varying the expressions (12), determining based integrated parameters from the error sensing elements (13), write a matrix of dimension N

where the nonzero elements are defined by the expression

when

L_{ODK}- the value of the increment of distance traveled on the odometer for the k-th iteration;the average values of the accelerations on the readings of accelerometers and incline railway (5.16) on the k-th iteration;

T_{k}the time characterizing the duration of the k-th iteration.

Then hold the odometer correction

The known method odometer correction [2] the speed of movement. This is done by integrating (aggregation) on the speed of the object obtained by the odometer and the strapdown inertial navigation system (beans), integrated satellite navigation system.

The divergence angles of pitch of the truck and body and the angle of the path determined by the longitudinal irregularities and fluctuations in the body on springs. Given the large base body (10 m) and the relatively small size of the asperities can be considered as average values of these angles are the same. If evaluations on two pillars, speed - vertical V_{GBR}and horizontal V_{Year}K) during the transition to the correction velocity is excluded from consideration. In this case, the odometer determined

where the angleproduced Ann. Varying expressions (15), we obtain equation errors

When integrating odometer and beans velocity vector of the parameters are based on the equations of errors (16), as follows

whereV_{INCH}and_{V}- the horizontal and vertical components of the error rate produced by the beans.

The matrix of the measurements in this case takes the form

and increment the path is calculated in accordance with formula.

Comparing the values of the velocities produced by the odometer with the appropriate indications Binns V_{H}and(10). Then the adjusted value of the increment of the path is determined in accordance with a ratio of

The disadvantage of the above methods is the relatively low accuracy, depending on the mode of motion of the object.

The objective of the invention is to develop a versatile method for correcting encoder, an error which does not depend on the mode and conditions of movement of the object.

To solve the problem in the correction method of the sensor sailed distance is implemented identification of the coefficients of the model error.

Model errors odometer, i.e. determine the sailed distance S, are in the form

whereS_{0}error initial exhibition; m0,0005 0,005...is the coefficient of sliding; m_{1}, m_{2}and m_{3}the coefficients of the dependence of the error on the velocity, acceleration and motion on curved track sections, radius R; V_{ML}- speed Dvizheniye measuring wheelsets during movement; S_{c}- error due to the unevenness of the path and vibrations of the car on the track,_{ml}- random instrumental error.

Identification of the coefficients in the model (19) is implemented on the basis of extreme-correlation method [4]. As the analyzed parameters are the measurement results and course angle during the passage of a single section of railway track "there" and "back". Using the reference point, the curved sections of the path.

In the estimated magnitude of the mismatch limit coordinates of the paths of the two passages

where k is the number of the curved section; K_{1,2}- the value of the course angle of the analyzed part of the way in the passages "there" and "back"; S waypoint coordinate; - increment track coordinates at which to evaluate the value of J_{k}.

Comparative analysis of the value of J changes with the characteristics of motion (speed, acceleration) and the magnitude of the curvature of the path in the plan allows you to determine the model coefficients (19). For ; _{3}=175 m; m*=0,03.

Thus, the proposed method allows to identify the model of sensor errors eaten path, which is used for correction of his testimony, and may also be involved in the damping sulanowski fluctuations scheme similar to the scheme damping inertial velocity from the log.

Sources of information

1. Inertial methods and means of determining motion parameters of interest: a textbook for courses “Design and construction of devices URA” and “Inertial navigation systems and management /C. I. Kupalov, A. C. Mochalov, A. M. Bronfin; Etu. SPb., 2000, 84.

2. A. M. Bronfin, A. C. Mochalov, M Rachel, I., Simister. The study integrated navigation system on the track.//A collection of articles and reports “Integrated inertial-satellite navigation system”. - SPb.: SSC RF-CSRI “Elektropribor”, 2001, S. 181-197.

3. Bronfin A. M., Gupalo C. I., A. Mochalov Century Integrated navigation system on the railway track on the basis of analytical girovertikal truncated structure// proceedings of the Etu "LETI", No. 1, 2002, S. 10-13.

4. Topisaw C. A., I. B. Wygant. Identification of strains of railway track using the.1. - S. 195.

1. The correction method of the sensor passed distance, namely, that on the basis of the digital filter to produce integration changes the geographical coordinates and the velocity of the object, obtained by processing information received from a satellite navigation system and channel navigation and orientation and odometer, then get an updated assessment of the accuracy of the odometer, which adjust the nominal value of its step, characterized in that depending on the mode of motion of an object change the transfer function of the digital filter in accordance with the model of sensor errors sailed distance

whereS_{0}error initial exhibition;

m0,0005÷0,005 - slip value;

l - intercept odometer;

m_{1}, m_{2}and m_{3}the coefficients of the dependence of the error on the velocity, acceleration and motion on curved track sections, radius R;

V_{ML}the speed odometer;

m* - factor, the nature of the AI;

S_{C}- error due to the unevenness of the path and vibrations of the carriage on the track;

_{ML}- random instrumental error.

2. The method according to p. 1, characterized in that as navigation and orientation using strapdown inertial navigation system.

3. The method according to p. 1, characterized in that as navigation and orientation using analytical girovertikal truncated structure.

4. The method according to p. 1, characterized in that the integration produced by the velocity of the object obtained by the odometer and the strapdown inertial navigation system, integrated satellite navigation system.

**Same patents:**

FIELD: railway transport; permanent way facilities.

SUBSTANCE: invention is designed for checking parameters of track. Proposed track gauge contains housing, device for measuring gauge width with movable and fixed stops to thrust against rail heads, rail level measuring device and device to measure ordinates and grooves of switches. Including vernier with stop to thrust against head of move-off rail or counterrail and interacting with digital indicators on gauge housing. Vernier is provided with additional stop to thrust against non-worn-out part of rail head. Rail side wear detector interacting with vernier is installed on gauge housing.

EFFECT: enlarged operating capabilities of track gauge, reduced errors in measurement.

2 cl, 3 dwg