Odometer parameter online calibration method and storage medium

Abstract

The invention relates to the technical field of measurement, in particular to a speedometer parameter online calibration method and a storage medium. The calibration method comprises the steps that the position of a carrier in a first mileage serves as a starting point, the position of the carrier in a second mileage serves as a terminal point, and the second mileage is the mileage that the carrier travels again on the basis of the first mileage; acquiring first position information of the carrier at the starting point; acquiring second position information of the carrier at the terminal point; acquiring a first speedometer parameter of the carrier according to the first position information and the second position information; acquiring a second odometer parameter of the carrier according to a preset odometer parameter of the carrier and the first odometer parameter; according to the fact that the variable quantity between the second odometer parameter and the preset odometer parameter is within the preset range, the target odometer parameter of the carrier is obtained. The method is simple and easy to implement, and the accuracy of the parameter calibration result of the speedometer is improved through the method.

Description

Technical Field

[0001] The present invention relates to the field of measurement technology, and in particular to an odometer parameter online calibration method and a storage medium. Background Art

[0002] The positioning and orientation system, which is composed of inertial navigation, satellite navigation, odometer and altimeter, realizes navigation and positioning through multi-information fusion. In order to ensure the high-precision attitude, speed and position output of the positioning and orientation equipment, the odometer parameters (scale factor error, heading installation deflection, pitch installation deflection) calibration must be completed before use. At present, the commonly used positioning and orientation system odometer parameter calibration methods include landmark point (high-precision position benchmark, landmark point) calibration method and filter calibration method. For landmark point calibration: high-precision position benchmark is expensive, and landmark points are at risk of being occupied; for filter calibration method: complex filter model needs to be established, and the calibration effect is not ideal when the model is inaccurate and the external information is inaccurate, and certain carrier maneuvers are required.

[0003] There are two existing odometer calibration technologies. One is to use the dead reckoning method to calculate the carrier position after the positioning and orientation system completes the initial alignment. After the carrier travels a certain distance to reach the specified position, the odometer parameter calibration is completed by using a high-precision position reference or the position value of the landmark point at the specified position and a related calculation method. This method has the problems of high cost, time-consuming disassembly and assembly of the position reference system, and the influence of the surrounding environment on the position of the landmark. The other is to establish a filtering calibration model related to the odometer parameters, and realize the odometer parameter calibration by introducing external information and using filtering technology. This method has the problems of inaccurate filtering model establishment, inaccurate external information and long parameter adjustment cycle. Summary of the invention

[0004] To solve at least one problem in the background technology, the present invention provides an odometer parameter online calibration method and a storage medium.

[0005] According to a first aspect of the present invention, the present invention provides an odometer parameter online calibration method, comprising the following steps:

[0006] Taking the position of the carrier in the first mile as the starting point, and the position of the carrier in the second mile as the end point, the second mile is the mileage traveled by the carrier on the basis of the first mileage;

[0007] Acquire first position information of the carrier at the starting point, the first position information including a first satellite navigation output position of the starting point, a first dead reckoning position, and a first travel distance of the starting point relative to a first starting point among the starting points;

[0008] Acquire second position information of the carrier at the destination, the second position information including a second satellite navigation output position of the destination, a second dead reckoning position, and a second travel distance of the destination relative to the first of the starting points;

[0009] Acquire a first odometer parameter of the carrier according to the first location information and the second location information;

[0010] Acquire a second odometer parameter of the carrier according to the preset odometer parameter of the carrier and the first odometer parameter;

[0011] According to the variation between the second odometer parameter and the preset odometer parameter being within a preset range, a target odometer parameter of the carrier is obtained.

[0012] According to one embodiment of the present invention, the carrier has i starting points in the first mileage, where i is a natural number, i≥1;

[0013] The carrier has j destinations in the second mileage, where j is a natural number, j≥i;

[0014] The mileages in the i starting points are not consistent;

[0015] The mileages in the j said end points are not consistent.

[0016] According to one embodiment of the present invention, among the i starting points, the distance between adjacent starting points is C1;

[0017] Among the j endpoints, the distance between adjacent endpoints is C2;

[0018] Where C1 and C2 are natural numbers, C1>0, C2>0;

[0019] The C2 is consistent with or inconsistent with the C1.

[0020] According to one embodiment of the present invention, the first end point in the second mileage is obtained according to the carrier traveling a further mileage C3 relative to the last starting point in the first mileage;

[0021] According to the mileage traveled by the carrier relative to the first terminal, obtaining other terminal points among the j terminal points;

[0022] Wherein C3 is a natural number, C3>C1, and C3>C2.

[0023] According to one embodiment of the present invention, the satellite navigation output position includes a first longitude, a first latitude and a first altitude; and the dead reckoning position includes a second longitude, a second latitude and a second altitude.

[0024] According to one embodiment of the present invention, a true displacement vector, a dead reckoning displacement vector, a driving mileage, and an elevation error of the endpoint are obtained according to the first satellite navigation output position, the first dead reckoning position, a first driving distance of the starting point relative to a first one of the starting points, the second satellite navigation output position, the second dead reckoning position, and a second driving distance of the endpoint relative to the first one of the starting points;

[0025] The first odometer parameter is obtained according to the real displacement vector, the dead reckoning displacement vector, the mileage and the elevation error; the first odometer parameter includes a scale factor error, a heading installation deflection error and a pitch installation deflection error.

[0026] According to one embodiment of the present invention, the preset odometer parameters include a preset scale factor, a preset heading installation deflection angle, and a preset pitch installation deflection angle;

[0027] Acquire a second odometer parameter according to the scale factor error, the heading installation deflection error, the pitch installation deflection error, the preset scale factor, the preset heading installation deflection, and the preset pitch installation deflection;

[0028] The second odometer parameters include a dead reckoning scale factor, a dead reckoning heading installation angle, and a dead reckoning pitch installation angle.

[0029] According to an embodiment of the present invention, the variation between the second odometer parameter and the preset odometer parameter being less than a preset range comprises:

[0030] A change between the calculated scaling factor in the second odometer parameter and the preset scaling factor in the preset odometer parameter is less than a preset range.

[0031] According to one embodiment of the present invention, after the change between the second odometer parameter and the preset odometer parameter is within a preset range, when there are i starting points and i>1, where i is a natural number, the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the end point are obtained, and the i second odometer parameters are accumulated and averaged to obtain the target odometer parameters.

[0032] According to one embodiment of the present invention, when there are i starting points and j end points, and i>1 and j>1, where i and j are natural numbers, the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the j end points are respectively obtained, and the i second odometer parameters of the j end points are accumulated and averaged to obtain the target odometer parameters.

[0033] According to one embodiment of the present invention, the second odometer parameter is accumulated and averaged, including:

[0034] Accumulating calibration results of the estimated scaling factors to obtain a target scaling factor in the target odometer parameter;

[0035] Accumulate the calibration results of the calculated heading installation deflection angle to obtain the target heading installation deflection angle in the target odometer parameter;

[0036] The calculated pitch installation deflection angle is calibrated and accumulated to obtain the target pitch installation deflection angle in the target odometer parameter.

[0037] According to a second aspect of the present invention, the present invention provides a storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above method when executed by a processor.

[0038] The present invention has the following beneficial effects:

[0039] The present invention realizes stable and reliable online calibration of odometer parameters by designing a reasonable starting point and end point of the carrier, adopting a preset range judgment and statistical calculation method, and can automatically update and store the latest calibration results, avoiding the problem that the calibration scheme needs marker points or the filtering method needs carrier maneuvering, and avoiding the problem of inaccurate model and inaccurate external information. Through the odometer parameter calibration method of the present invention, the calibration method is simple and easy to implement, which can not only improve the accuracy of the calibration result, but also improve the work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A flow chart of the online calibration method of odometer parameters of the present invention is shown;

[0041] Figure 2 A schematic diagram of the online calibration path of the odometer parameters of the present invention is shown. DETAILED DESCRIPTION

[0042] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, rather than implying any limitation on the scope of the present disclosure.

[0043] As used herein, the term "including" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "based at least in part on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0044] This embodiment discloses an online calibration method for odometer parameters. Figure 1 As shown, the following steps are included:

[0045] Taking the position of the carrier in the first mile as the starting point, and the position of the carrier in the second mile as the end point, the second mile is the mileage traveled by the carrier on the basis of the first mileage;

[0046] Acquire first position information of the carrier at the starting point, the first position information including a first satellite navigation output position of the starting point, a first dead reckoning position, and a first travel distance of the starting point relative to a first starting point among the starting points;

[0047] Acquire second position information of the carrier at the destination, the second position information including a second satellite navigation output position of the destination, a second dead reckoning position, and a second travel distance of the destination relative to the first of the starting points;

[0048] Acquire a first odometer parameter of the carrier according to the first location information and the second location information;

[0049] Acquire a second odometer parameter of the carrier according to the preset odometer parameter of the carrier and the first odometer parameter;

[0050] According to the variation between the second odometer parameter and the preset odometer parameter being within a preset range, a target odometer parameter of the carrier is obtained.

[0051] In this embodiment, the method of obtaining position information does not require an external position reference or landmark point, and the odometer parameters of the positioning and orientation system are fully autonomously calibrated. The satellite navigation is a satellite receiver, and the position information provided by the satellite receiver does not have an absolute high-precision requirement, thereby improving work efficiency. By using a method in which the change between the second odometer parameter and the preset odometer parameter is within a preset range, unreasonable calibration results can be automatically eliminated to improve the accuracy of the calibration results. Through the odometer parameter calibration method of the present invention, the calibration method is simple and easy to implement, which can not only improve the accuracy of the calibration results, but also improve work efficiency.

[0052] In some embodiments, the preset odometer parameters in the carrier are updated to the obtained target odometer parameters, and the odometer parameters are automatically updated and stored, and applied in actual engineering. The method of this embodiment can automatically update and store the latest calibration results, avoiding the problem that the calibration scheme requires landmark points or the filtering method requires carrier maneuvers, and avoiding inaccurate models and inaccurate external information.

[0053] According to one embodiment of the present invention, the carrier has i starting points in the first mileage, where i is a natural number, i≥1;

[0054] The carrier has j destinations in the second mileage, where j is a natural number, j≥i;

[0055] The mileages in the i starting points are not consistent;

[0056] The mileages in the j said end points are not consistent.

[0057] In this embodiment, the carrier has i starting points in the first mileage, that is, the carrier stops i times in the first mileage, and the position where the carrier stops each time in the first mileage is taken as the starting point, then the carrier has i starting points. The carrier has j end points in the second mileage, that is, the carrier stops j times in the second mileage, and the position where the carrier stops each time in the second mileage is taken as the end point, then the carrier has j end points. This embodiment makes full use of the existing equipment of the positioning and orientation system, and realizes stable and reliable online calibration of odometer parameters by designing reasonable starting points and end points, and adopting preset range judgment and statistical calculation methods.

[0058] In some embodiments, i≥3, j≥5, so as to ensure the accuracy of the calibration result.

[0059] Preferably, if Figure 2 As shown in the figure, i = 3, j = 5. In this way, the calibration time is reduced and the work efficiency is improved while ensuring the accuracy of the calibration result.

[0060] In some embodiments, when there are i starting points in the first mileage and j end points in the second mileage, each starting point has first position information, each end point has second position information, the first driving distance of each starting point is the driving distance of the starting point relative to the first starting point, and the second driving distance of each end point is the driving distance of the end point relative to the first starting point.

[0061] According to an embodiment of the present invention, among the i starting points, the distance between adjacent starting points is C1; among the j end points, the distance between adjacent end points is C2;

[0062] Where C1 and C2 are natural numbers, C1>0, C2>0;

[0063] The C2 is consistent with or inconsistent with the C1.

[0064] In this embodiment, when i=3, there are 3 starting points. According to the vehicle during the driving process, the 3 starting points are recorded as the first starting point, the second starting point and the third starting point in sequence. Then the distance between the first starting point and the second starting point is C1, the distance between the second starting point and the third starting point is C1, and the distance between the first starting point and the third starting point is 2C1. The distance between adjacent end points is the same as the above-mentioned analysis of the starting point. The sum of C2 of all starting points is the first mileage. Specifically, the position of the third starting point is the last position reached by the vehicle in the first mileage.

[0065] In some embodiments, C1 is 10-50 m and C2 is 10-50 m.

[0066] According to one embodiment of the present invention, the first end point in the second mileage is obtained according to the carrier traveling a further mileage C3 relative to the last starting point in the first mileage;

[0067] According to the mileage traveled by the carrier relative to the first terminal, obtaining other terminal points among the j terminal points;

[0068] Wherein C3 is a natural number, C3>C1, and C3>C2.

[0069] In this embodiment, when there are 3 starting points and 5 end points, the distance between the third starting point and the first end point is C3, that is, the position reached by the carrier after traveling C3 distance from the third starting point as the starting point is the first end point. The position reached by the carrier after traveling C2 distance based on the first end point is the second starting point, and so on to obtain the remaining end points among the j end points, and the sum of C3 and C2 of all the end points is the second mileage.

[0070] According to one embodiment of the present invention, the satellite navigation output position includes a first longitude, a first latitude and a first altitude; and the dead reckoning position includes a second longitude, a second latitude and a second altitude.

[0071] In this embodiment, the satellite navigation output position and the dead reckoning position only require longitude, latitude and altitude information, so that the accuracy of the odometer parameter calibration result is improved while reducing the difficulty of obtaining the information source.

[0072] Specifically, the first satellite output position is:

[0073] ;

[0074] Where P WQi is the output position of the first satellite, λ WQ , L WQ 、h WQ They represent the longitude, latitude and altitude of the starting point output by the satellite navigation (satellite receiver) at time T, respectively. Then λ WQi , L WQi 、h WQi They represent the longitude, latitude and altitude of the i-th starting point output by the satellite navigation at time T, specifically (i=1,2,3).

[0075] in, ;

[0076] The calculation method of the first satellite output position is as follows:

[0077] ;

[0078] In the formula, , , They represent the longitude, latitude and altitude output of the satellite navigation at time t, Qi is the i-th starting point, that is, , , They represent the longitude, latitude and altitude of the i-th starting point output by the satellite navigation, specifically (i=1,2,3).

[0079] The first dead reckoning position is:

[0080] ;

[0081] Where P DQi is the first dead reckoning position, λ DQ , L DQ 、h DQ Respectively represent the longitude, latitude and altitude of the starting point at time T, then λ DQi , L DQi 、hDQi They represent the longitude, latitude and altitude of the i-th starting point at time T, specifically (i=1,2,3).

[0082] The first driving distance is: ;

[0083] In the formula, △S Qi is the driving distance of the i-th starting point, specifically (i=1,2,3).

[0084] The second satellite output position is:

[0085] ;

[0086] Where P WZj is the output position of the second satellite guide, λ WZ , L WZ 、h WZ They are respectively represented by the longitude, latitude and altitude of the destination output by the satellite navigation (satellite receiver) at time T, then λ WZj , L WZj 、h WZj They represent the longitude, latitude and altitude of the jth endpoint output by the satellite navigation at time T, specifically (j=1,2,3,4,5).

[0087] The calculation method of the second satellite guide output position is the same as the calculation method of the first satellite guide output position;

[0088] The calculation method of the second satellite output position is as follows:

[0089] .

[0090] In the formula, , , They represent the longitude, latitude and altitude output of the satellite navigation (satellite receiver) at time t, and Zj is the jth end point, that is, , , They represent the longitude, latitude and altitude of the jth endpoint output by the satellite navigation. Specifically (j=1,2,3,4,5).

[0091] The second dead reckoning position is:

[0092] ;

[0093] Where P DZj is the second dead reckoning position, λ DZ , L DZ 、h DZRespectively represent the longitude, latitude and altitude of the end point at time T, then λ DZj , L DZj 、h DZj They represent the longitude, latitude and altitude of the j-th endpoint at time T, specifically (j=1,2,3,4,5).

[0094] The second driving distance is: ;

[0095] In the formula, △S Zj is the driving distance to the jth destination, specifically (j=1,2,3,4,5).

[0096] According to one embodiment of the present invention, a true displacement vector, a dead reckoning displacement vector, a driving mileage, and an elevation error of the endpoint are obtained according to the first satellite navigation output position, the first dead reckoning position, a first driving distance of the starting point relative to a first one of the starting points, the second satellite navigation output position, the second dead reckoning position, and a second driving distance of the endpoint relative to the first one of the starting points;

[0097] acquiring the first odometer parameter according to the real displacement vector, the dead reckoning displacement vector, the mileage, and the elevation error;

[0098] The first odometer parameters include a scale factor error, a heading installation angle error, and a pitch installation angle error.

[0099] In this embodiment, the online calculation of the first odometer parameter of the carrier at the end point is realized by the following formula;

[0100] The actual displacement vector of the carrier at the end point is calculated as follows:

[0101] ;

[0102] The dead reckoning displacement vector of the vehicle at the endpoint is calculated as follows:

[0103] ;

[0104] The mileage of the carrier at the destination is calculated as follows:

[0105] ;

[0106] The elevation error of the carrier at the end point is calculated as follows:

[0107] ;

[0108] In the formula, is the altitude of the jth dead reckoning endpoint, Output the height of the j-th endpoint for the satellite navigation.

[0109] The scale factor error of the first odometer is calculated as follows:

[0110] ;

[0111] The calculation method of the heading installation deflection error of the first odometer is as follows:

[0112] ;

[0113] Where Z is the vector With vector The third component after the cross product.

[0114] The pitch installation deflection error of the first odometer is calculated as follows:

[0115] .

[0116] In the above formula (i=1,2,3; j=1,2,3,4,5).

[0117] Through the above formula, three sets of calibration results at the end point (first odometer parameters) can be calculated: , They are scale factor error, heading installation angle error and pitch installation angle error, respectively.

[0118] The second odometer parameter is accumulated and averaged, including:

[0119] Accumulating calibration results and counting results of the estimated scaling factor to obtain a target scaling factor in the target odometer parameter;

[0120] Accumulate the calibration results and the counting results of the calculated heading installation deflection angle to obtain the target heading installation deflection angle in the target odometer parameter;

[0121] The calculated pitch installation deflection angle is calibrated and counted to obtain a target pitch installation deflection angle in the target odometer parameter.

[0122] According to one embodiment of the present invention, the preset odometer parameters include a preset scale factor, a preset heading installation deflection angle, and a preset pitch installation deflection angle;

[0123] Acquire a second odometer parameter according to the scale factor error, the heading installation deflection error, the pitch installation deflection error, the preset scale factor, the preset heading installation deflection, and the preset pitch installation deflection;

[0124] The second odometer parameters include a dead reckoning scale factor, a dead reckoning heading installation angle, and a dead reckoning pitch installation angle.

[0125] In this embodiment, the calculation formulas for the scale factor, the heading installation deflection angle, and the pitch installation deflection angle are:

[0126] ;

[0127] In the formula, , , Respectively represent the scale factor, heading installation deflection angle, and pitch installation deflection angle of the preset odometer parameters; , , They respectively represent the latest calibration results of the scale factor, heading installation deflection angle, and pitch installation deflection angle of the j-th end point relative to the ith starting point.

[0128] According to an embodiment of the present invention, the variation between the second odometer parameter and the preset odometer parameter being less than a preset range comprises:

[0129] A change between the calculated scaling factor in the second odometer parameter and the preset scaling factor in the preset odometer parameter is less than a preset range.

[0130] In this embodiment, since the changes in the heading installation deflection angle and the pitch installation deflection angle in the odometer parameters are relatively small, the odometer scale factor changes significantly, so the second odometer scale factor parameter obtained by calculation is Preset odometer parameters and preset scaling factors Comparisons are made using the following formula:

[0131] ;

[0132] Where ρ is the preset range, and the value range of ρ is 0.003~0.005.

[0133] If the change between the scaling factor in the second odometer parameter and the preset scaling factor in the preset odometer parameter is less than the preset range ρ, the calibration result of the second odometer parameter is considered to be credible, thereby realizing automatic screening of the calibration result.

[0134] According to one embodiment of the present invention, after the change between the second odometer parameter and the preset odometer parameter is within a preset range, when there are i starting points and i>1, where i is a natural number, the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the end point are obtained, and the i second odometer parameters are accumulated and averaged to obtain the target odometer parameters.

[0135] In this embodiment, by obtaining the second odometer parameters that the carrier has when it is at the end point relative to the i starting points, the accuracy of the odometer parameter calibration result is further improved.

[0136] According to one embodiment of the present invention, when there are i starting points and j end points, and i>1 and j>1, where i and j are natural numbers, the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the j end points are respectively obtained, and the i second odometer parameters of the j end points are accumulated and averaged to obtain the target odometer parameters.

[0137] In this embodiment, specifically, one end point has i second odometer parameters, and j end points respectively obtain i second odometer parameters of each end point. By respectively obtaining the second odometer parameters that the carrier has when it is located at the j end points relative to the i starting points, the accuracy of the odometer parameter calibration result is further improved.

[0138] According to one embodiment of the present invention, the second odometer parameter is accumulated and averaged, including:

[0139] Accumulating calibration results of the estimated scaling factors to obtain a target scaling factor in the target odometer parameter;

[0140] Accumulate the calibration results of the calculated heading installation deflection angle to obtain the target heading installation deflection angle in the target odometer parameter;

[0141] The calculated pitch installation deflection angle is calibrated and accumulated to obtain the target pitch installation deflection angle in the target odometer parameter.

[0142] In this embodiment, the second odometer parameter calibration results are accumulated, and the final target odometer parameter calibration result is determined by the following formula:

[0143] ;

[0144] In the formula, They are the target scaling factor, target heading installation deflection angle, and target pitch installation deflection angle of the target odometer parameters, respectively (i=1,2,3; j=1,2,3,4,5).

[0145] The preset odometer parameters are then updated to the target odometer parameters, thereby realizing online calibration and automatic update storage of the odometer parameters for alignment and navigation by the positioning and orientation system.

[0146] According to one embodiment of the present invention, a storage medium stores a computer program, which implements the steps of the above method when executed by a processor.

[0147] This article gives the following explanation:

[0148] 1. Principle of odometer dead reckoning:

[0149] The odometer measures the wheel rotation output sampling period Mileage increment of vehicles ,in, is the number of pulses output per cycle of the odometer, is the odometer scale factor. Define the vehicle coordinate system m, and the mileage increment of the odometer output per cycle is:

[0150] ;

[0151] In the formula, Representation Matrix The transpose of .

[0152] There is an installation relationship between the inertial navigation and the odometer, and there is a pitch installation angle between the m system and the j system. , Rolling installation angle and azimuth installation angle . Define the m system relative to the j system when the head Positive, right-leaning Positive, when turning right is positive, then the transformation matrix from j system to m system It can be expressed as:

[0153] ;

[0154] In the formula, the symbol express , express .

[0155] The mileage increment of the odometer output in the j system is:

[0156] ;

[0157] In the formula, Represents the component of mileage increment in the j system.

[0158] Furthermore, the n-series mileage increment can be obtained:

[0159] ;

[0160] In the formula, Represents the components of the mileage increment in the n system, including the east component , north component and the celestial component ; Represents the transformation matrix from system j to system n at time t-1.

[0161] The position update algorithm for dead reckoning can be obtained:

[0162] ;

[0163] ;

[0164] ;

[0165] In the formula, , Respectively represent the longitude at time t-1 and time t; , Respectively represent the latitude at time t-1 and time t; , Respectively represent the height at time t-1 and time t; and They represent the meridian radius and the meridian radius of the earth respectively.

[0166] 2. Dead reckoning error analysis:

[0167] Ignoring small errors, the position increment error of each cycle of dead reckoning can be obtained :

[0168] ;

[0169] In the formula, , It can be considered basically unchanged. It can also be approximated to a constant value within a certain period of time. Integrating it gives the position error model:

[0170] ;

[0171] In the formula, is the position error generated during driving; is the total displacement of the vehicle, is the total mileage of the vehicle.

[0172] In the formula, displacement represents the displacement vector between the starting and ending positions, and the mileage Indicates the length of the route traveled.

[0173] Projecting the above formula in the horizontal direction, we can get:

[0174] ;

[0175] In the formula, for The horizontal component of ; for The horizontal component of .

[0176] Projecting the above formula in the height direction, we can get:

[0177] ;

[0178] In the formula, is the elevation error of the starting and ending positions of the vehicle. Very small, so The resulting height error is very small.

[0179] Example 1

[0180] The online calibration path of odometer parameters is as follows: Figure 2 As shown, the calibration scheme of this embodiment includes 3 starting points and 5 end points. Figure 2 In, L Q12 , L Q23 , L Z12 , L Z23 , L Z34 , L Z45 The range is 10m~50m; L QZ The range is 5km~10km; the 3 starting points and 5 end points are selected in open and unobstructed locations. By obtaining the reference position, dead reckoning position and driving distance of these 8 points, the corresponding calculation method and data selection scheme are used to obtain the online calibration results of the odometer parameters.

[0181] 1. The specific implementation scheme for online calibration of odometer parameters is as follows:

[0182] 1.1 The positioning and orientation system is powered on and initialized at starting point 1, and the initial alignment begins;

[0183] 1.2 At starting point 1, record the satellite receiver (satellite navigation) T QZ The average position output in seconds , and use this position as the starting position for dead reckoning , record the distance from starting point 1 to starting point 1 ;in, The calculation is as follows:

[0184] ;

[0185] In the formula, , , They represent the longitude, latitude and altitude output of the satellite receiver at time t respectively.

[0186] 1.3 After completing the initial alignment at starting point 1, the vehicle travels a distance L Q12 Arrive at starting point 2 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from starting point 2 to starting point 1 ;

[0187] 1.4 The vehicle travels a distance L Q23 Arrive at starting point 3 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from starting point 3 to starting point 1 ;

[0188] 1.5 The vehicle travels a distance L QZ Arrived at the end point 1, record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from the end point 1 to the starting point 1 ;

[0189] 1.6 At end point 1, use the parameters at end point 1 ( , , ) and the parameters of starting point 1 ( , , ), parameters of starting point 2 ( , , ) and the parameters of starting point 3 ( , , ). The first odometer parameter of the carrier at the end point 1 is calculated online using the following formula:

[0190] True displacement vector:

[0191] ;

[0192] Dead Reckoning Displacement Vector:

[0193] ;

[0194] Mileage:

[0195] ;

[0196] Elevation error:

[0197] ;

[0198] In the formula, is the altitude of the jth dead reckoning endpoint, Output the height of the j-th endpoint for the satellite navigation.

[0199] Scale factor error of the first odometer:

[0200] ;

[0201] The heading installation deflection error of the first odometer:

[0202] ;

[0203] The pitch installation deflection error of the first odometer:

[0204] ;

[0205] In the above formula, , By using the above formula, three sets of calibration results at end point 1 can be calculated: When i=1, it is the first set of calibration results at end point 1; when i=2, it is the second set of calibration results at end point 1; when i=3, it is the third set of calibration results at end point 1. They are the scale factor error of end point 1, the heading installation deflection error, and the pitch installation deflection error.

[0206] 1.7 The vehicle travels a distance L Z12 Arrive at the end point 2 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from the end point 2 to the start point 1 ;

[0207] Same as step 1.6, three sets of calibration results at end point 2 can be calculated .

[0208] 1.8 The vehicle travels a distance L Z23 Arrive at the end point 3 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from the end point 3 to the starting point 1 ;

[0209] Same as step 1.6, three sets of calibration results at end point 3 can be calculated .

[0210] 1.9 The vehicle travels a distance L Z34 Arrive at the end point 4 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from the end point 4 to the starting point 1 ;

[0211] Same as step 1.6, three sets of calibration results at end point 4 can be calculated .

[0212] 1.10 The vehicle travels a distance L Z45 Arrive at the end point 5 and record the satellite receiver T here QZ The average position output in seconds (Calculation method is the same as ), dead reckoning position and the distance from the end point 5 to the starting point 1 ;

[0213] Same as step 1.6, three sets of calibration results at end point 5 can be calculated .

[0214] Among them, T QZ It is 30, which means recording the average position output of the satellite receiver within 30 seconds.

[0215] In this article, starting points 1 / 2 / 3 are equivalent to the first / second / third starting points, and end points 1 / 2 / 3 / 4 / 5 are equivalent to the first / second / third / fourth / fifth end points. They just express the same concept in different ways.

[0216] 1.11 After obtaining 15 sets of calibration results for the above five endpoints, data screening can be performed.

[0217] 2. Odometer parameter online calibration data processing

[0218] 2.1 Parameter calculation

[0219] After obtaining the above 3 starting points and 15 groups of endpoint calibration results, the estimated scaling factor, estimated heading installation deflection angle, and estimated pitch installation deflection angle of the second odometer parameters are calculated by the following formula:

[0220] ;

[0221] In the formula, , , They respectively represent the preset scale factor, preset heading installation deflection angle, and preset pitch installation deflection angle of the original storage (preset odometer parameters); , , It represents the latest calibration results of the estimated scale factor, estimated heading installation deflection angle, and estimated pitch installation deflection angle of the j-th end point relative to the i-th starting point.

[0222] 2.2 Parameter screening and calibration result determination

[0223] In the actual positioning and orientation system, since the changes in the heading and pitch installation deflection angles are relatively small, the odometer scale factor changes significantly, so the 15 sets of calculations are Preset scaling factor with original stored value Comparisons are made using the following formula:

[0224] ;

[0225] Where ρ is the preset range, and the value range of ρ is 0.003~0.005.

[0226] If the difference between the calculated scale factor and the preset scale factor is less than or equal to the set threshold (preset range) ρ, the calibration results of this set of odometer parameters are considered credible. If the difference between the calculated scale factor and the preset scale factor is greater than the set threshold ρ, the calibration results of this set are considered unreliable.

[0227] The unreliable odometer parameter calibration results are eliminated, and the remaining reliable odometer parameter calibration results are selected to accumulate the calibration results to obtain the final target odometer parameter calibration results. The final target odometer parameter calibration results are determined by the following formula:

[0228] ;

[0229] In the formula, They are target scale factor, target heading installation deflection angle, and target pitch installation deflection angle, respectively (i=1,2,3; j=1,2,3,4,5).

[0230] Alternatively, the unreliable calibration results are recalibrated until the calibration results are reliable, and the calibration results of all groups are accumulated to obtain the final target odometer parameter calibration results.

[0231] 2.3 Parameter Storage

[0232] After obtaining the final calibration result through step 2.2, the original stored value Update to target odometer parameters , thereby completing the online calibration and automatic update storage of the odometer parameters for the positioning and orientation system to perform alignment and navigation.

[0233] Example 2

[0234] This example provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in the above-mentioned embodiment 1 are implemented.

[0235] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present disclosure, and in actual applications, various changes may be made thereto in form and detail without departing from the scope of the present disclosure.

Claims

1. An online calibration method for odometer parameters, characterized in that: The steps include: Taking the position of the carrier in the first mile as the starting point, and the position of the carrier in the second mile as the end point, the second mile is the mileage traveled by the carrier on the basis of the first mileage; Acquire first position information of the carrier at the starting point, the first position information including a first satellite navigation output position of the starting point, a first dead reckoning position, and a first travel distance of the starting point relative to a first starting point among the starting points; Acquire second position information of the carrier at the destination, the second position information including a second satellite navigation output position of the destination, a second dead reckoning position, and a second travel distance of the destination relative to the first of the starting points; Acquire a first odometer parameter of the carrier according to the first location information and the second location information; Acquire a second odometer parameter of the carrier according to the preset odometer parameter of the carrier and the first odometer parameter; According to the variation between the second odometer parameter and the preset odometer parameter being within a preset range, a target odometer parameter of the carrier is obtained.

2. The method for online calibration of odometer parameters according to claim 1, characterized in that: The carrier has i starting points in the first mileage, where i is a natural number, i≥1; The carrier has j destinations in the second mileage, where j is a natural number, j≥i; The mileages in the i starting points are not consistent; The mileages in the j said end points are not consistent.

3. The method for online calibration of odometer parameters according to claim 2, characterized in that: Among the i starting points, the distance between adjacent starting points is C1; among the j end points, the distance between adjacent end points is C2; Where C1 and C2 are natural numbers, C1>0, C2>0; The C2 is consistent with or inconsistent with the C1.

4. The method for online calibration of odometer parameters according to claim 3, characterized in that: According to the distance traveled by the carrier relative to the last starting point in the first mileage being C3, a first end point in the second mileage is obtained; According to the mileage traveled by the carrier relative to the first terminal, obtaining other terminal points among the j terminal points; Wherein C3 is a natural number, C3>C1, and C3>C2.

5. The method for online calibration of odometer parameters according to claim 1, characterized in that: The satellite navigation output position includes a first longitude, a first latitude and a first altitude; the dead reckoning position includes a second longitude, a second latitude and a second altitude.

6. The method for online calibration of odometer parameters according to claim 5, characterized in that: acquiring a true displacement vector, a dead reckoning displacement vector, a driving mileage, and an elevation error of the endpoint according to the first satellite navigation output position, the first dead reckoning position, a first driving distance of the starting point relative to a first one of the starting points, the second satellite navigation output position, the second dead reckoning position, and a second driving distance of the endpoint relative to the first one of the starting points; acquiring the first odometer parameter according to the real displacement vector, the dead reckoning displacement vector, the mileage, and the elevation error; The first odometer parameters include a scale factor error, a heading installation angle error, and a pitch installation angle error.

7. The method for online calibration of odometer parameters according to claim 6, characterized in that: The preset odometer parameters include a preset scale factor, a preset heading installation deflection angle, and a preset pitch installation deflection angle; Acquire a second odometer parameter according to the scale factor error, the heading installation deflection error, the pitch installation deflection error, the preset scale factor, the preset heading installation deflection, and the preset pitch installation deflection; The second odometer parameters include a dead reckoning scale factor, a dead reckoning heading installation angle, and a dead reckoning pitch installation angle.

8. The method for online calibration of odometer parameters according to claim 7, characterized in that: The variation between the second odometer parameter and the preset odometer parameter being less than a preset range includes: A change between the calculated scaling factor in the second odometer parameter and the preset scaling factor in the preset odometer parameter is less than a preset range.

9. The method for online calibration of odometer parameters according to claim 1, characterized in that: After the change between the second odometer parameter and the preset odometer parameter is within a preset range, when there are i starting points and i>1, where i is a natural number, obtain the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the end point, accumulate and average the i second odometer parameters, and obtain the target odometer parameter.

10. The method for online calibration of odometer parameters according to claim 1, characterized in that: After the change between the second odometer parameter and the preset odometer parameter is within a preset range, when there are i starting points and j end points, and i>1 and j>1, where i and j are natural numbers, the second odometer parameters of the carrier relative to the i starting points when the carrier is located at the j end points are respectively obtained, and the i second odometer parameters of the j end points are respectively added and averaged to obtain the target odometer parameters.

11. The method for online calibration of odometer parameters according to claim 9 or 10, characterized in that: The second odometer parameter is accumulated and averaged, including: According to the second odometer parameters including a dead reckoning scale factor, a dead reckoning heading installation angle and a dead reckoning pitch installation angle; Accumulating calibration results of the estimated scaling factors to obtain a target scaling factor in the target odometer parameter; Accumulate the calibration results of the calculated heading installation deflection angle to obtain the target heading installation deflection angle in the target odometer parameter; The calculated pitch installation deflection angle is calibrated and accumulated to obtain the target pitch installation deflection angle in the target odometer parameter.

12. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 11 are implemented.

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