A method and device for correcting corner measurement error

Abstract

The application provides a kind of corner measurement error correction method and device, in the application, after obtaining the initial value of the corner measured by corner sensor, the initial value of the corner is corrected based on the corner correction rule, and the corner correction value is obtained.Because the corner correction rule includes the parameter value of the pre-determined corner correction parameter, the parameter value of the corner correction parameter is the minimum candidate value of the measurement error, which is filtered out from the candidate value of the corner correction parameter based on the corresponding relationship between the historical left and right corner measurement values and the left and right corner measurement theoretical values determined in advance based on the corner spatial geometric relationship of the current vehicle, that is, when filtering the parameter value of the corner correction parameter, the corner spatial geometric relationship of the current vehicle is considered, and the selected parameter value is more consistent with the current vehicle condition, so that the accuracy of the selected parameter value is higher, and the accuracy of the corner correction based on the parameter value is higher.

Description

Technical Field

[0001] This invention relates to the field of angle measurement, and more specifically, to a method and apparatus for correcting angle measurement errors. Background Technology

[0002] Vehicle steering angle sensors are typically installed on one side of the steering axle. When using steering angle sensors to measure steering angle, a parallelogram-shaped mounting bracket structure is generally used. In this case, the rotation angle of the steering angle sensor is equal to the rotation angle of the wheel kingpin. Thus, by measuring the rotation angle of the steering angle sensor, the rotation angle of the wheel kingpin can be determined, thereby realizing the wheel steering angle measurement.

[0003] However, in existing angle measurement solutions, due to quality control issues at the factory and long-term use, the mounting bracket may deform, causing the rotation angle of the angle sensor and the rotation angle of the wheel kingpin to no longer conform to the ideal parallelogram relationship. That is, the angle value measured by the angle sensor is no longer equal to the kingpin rotation angle. This results in a difference between the angle measured by the sensor and the actual wheel angle, leading to low accuracy in angle measurement. Summary of the Invention

[0004] In view of this, the present invention provides a method and apparatus for correcting the angle measurement error, so as to solve the problem of low accuracy in angle measurement.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for correcting angle measurement errors includes:

[0007] The initial value of the turning angle is obtained from the measurement of the turning angle sensor; the turning angle sensor includes a left turning angle sensor and a right turning angle sensor installed on the vehicle where the turning angle sensor is located; the initial value of the turning angle includes the initial value of the left turning angle and the initial value of the right turning angle;

[0008] Obtain the corner correction rule, which is a mapping relationship between the initial corner value and the corner correction value. The corner correction rule includes the parameter values ​​of the predetermined corner correction parameter. The parameter values ​​of the corner correction parameter are selected from the candidate values ​​of the corner correction parameter based on the correspondence between the historical left and right corner measurement values ​​and the theoretical values ​​of the left and right corner measurement determined in advance based on the corner spatial geometry of the current vehicle, and the candidate value with the smallest measurement error.

[0009] The initial angle value is corrected using the aforementioned angle correction rule to obtain the angle correction value.

[0010] Optionally, the process of determining the parameter value of the angle correction parameter includes:

[0011] Obtain the correspondence between the theoretical values ​​of the left and right turning angles, which are pre-determined based on the current vehicle's turning angle spatial geometry.

[0012] Determine candidate values ​​for the angle correction parameter;

[0013] Obtain historical left and right corner measurement values; the historical left and right corner measurement values ​​include historical left corner measurement values ​​and historical right corner measurement values ​​corresponding to the historical left corner measurement values;

[0014] Based on the correspondence between the historical left and right turning angle measurements and the theoretical left and right turning angle measurements, an iterative optimization operation is performed on the candidate values ​​of the turning angle correction parameter to obtain the candidate values ​​of the turning angle correction parameter with the smallest measurement error, and these candidate values ​​are used as the parameter values ​​of the turning angle correction parameter.

[0015] Optionally, determining candidate values ​​for the angle correction parameter includes:

[0016] Obtain the theoretical values ​​of the steering angle correction parameters; the steering angle correction parameters include the parameters of the left and right sensor mounting brackets and the steering trapezoidal parameters;

[0017] Based on the installation accuracy of the left and right sensor mounting brackets and the steering trapezoid, the parameter traversal range of the steering angle correction parameters is determined.

[0018] Determine candidate values ​​for the theoretical value within the range of the parameter traversal.

[0019] Optionally, obtain historical left and right corner measurements, including:

[0020] Obtain multiple sets of historical left-turn angle measurements, and obtain the historical right-turn angle measurements corresponding to each set of historical left-turn angle measurements.

[0021] Optionally, based on the correspondence between the historical left and right turning angle measurements and the theoretical left and right turning angle measurements, an iterative optimization operation is performed on the candidate values ​​of the turning angle correction parameter to obtain the candidate values ​​of the turning angle correction parameter with the minimum measurement error, including:

[0022] For the candidate values ​​of the turning angle correction parameter, the estimated value of the historical right turning angle corresponding to the historical left turning angle measurement value is calculated based on the correspondence between the historical left turning angle measurement value and the theoretical values ​​of the left and right turning angle measurements.

[0023] Calculate the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value;

[0024] The historical right-turn angle estimates with the smallest measurement error are selected, and candidate values ​​for the angle correction parameters corresponding to the selected historical right-turn angle estimates are determined.

[0025] Optionally, based on the correspondence between the historical left-turn angle measurement values ​​and the theoretical values ​​of the left and right turn angle measurements, the estimated historical right-turn angle value corresponding to the historical left-turn angle measurement value is calculated, including:

[0026] A calculation formula is used to obtain the estimated historical right turn value corresponding to the historical left turn angle measurement value. The calculation formula includes the correspondence between the historical left turn angle measurement value, the angle correction parameter, and the historical right turn angle measurement value.

[0027] Optionally, the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value is calculated, including:

[0028] Calculate the difference between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value;

[0029] Calculate the sum of squares or the sum of absolute values ​​of the differences, wherein the sum of squares or the sum of absolute values ​​of the differences is taken as the measurement error.

[0030] Optionally, the initial angle value is corrected using the angle correction rule to obtain the angle correction value, including:

[0031] Obtain the angle correction formula and substitute the initial angle value into the angle correction formula to obtain the angle correction value.

[0032] Optionally, the corner correction formula includes a left corner correction formula and a right corner correction formula; the left corner correction formula is:

[0033] θ′ left =g l (θ left ,ALl1,ALl2,ALl3,ALl4,ALθ L );

[0034] Among them, g l Represents the function, θ' letf θ is the left turn angle correction value. left The initial values ​​for the left turn angle are ALl1, ALl2, ALl3, ALl4, and ALθ. L These are the parameters for corner correction;

[0035] The formula for correcting the right turn angle is:

[0036] θ′ right =g R (θ right , ARl1, ARl2, ARl3, ARl4, ARθ L )

[0037] Among them, g RRepresents the function, θ' right θ is the right turn correction value. right The initial values ​​for the right turn angle are: ARl1, ARl2, ARl3, ARl4, ARθ. L These are the parameters for corner correction.

[0038] A device for correcting angle measurement errors, comprising:

[0039] An initial value acquisition module is used to acquire the initial angle value measured by the angle sensor; the angle sensor includes a left angle sensor and a right angle sensor installed on the vehicle where the angle sensor is located; the initial angle value includes the initial left angle and the initial right angle.

[0040] The rule acquisition module is used to acquire the corner correction rule, which is a mapping relationship between the initial corner value and the corner correction value. The corner correction rule includes the parameter values ​​of the pre-determined corner correction parameters. The parameter values ​​of the corner correction parameters are selected from the candidate values ​​of the corner correction parameters based on the correspondence between the historical left and right corner measurement values ​​and the theoretical left and right corner measurement values ​​determined in advance based on the corner spatial geometry of the current vehicle, and the candidate value with the smallest measurement error.

[0041] The corner correction module is used to correct the initial corner value using the corner correction rule to obtain the corner correction value.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] This invention provides a method and apparatus for correcting steering angle measurement errors. In this invention, after obtaining the initial steering angle value measured by the steering angle sensor, the initial steering angle value is corrected based on a steering angle correction rule to obtain a corrected steering angle value. Since the steering angle correction rule includes predetermined steering angle correction parameter values, these parameter values ​​are selected from candidate values ​​based on the correspondence between historical left and right steering angle measurements and theoretical left and right steering angle measurements determined in advance based on the current vehicle's steering angle spatial geometry. In other words, when selecting the steering angle correction parameter values, the current vehicle's steering angle spatial geometry is considered, and the selected parameter values ​​better match the current vehicle condition, resulting in higher accuracy. Therefore, the accuracy of steering angle correction based on these parameter values ​​is also higher. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of an ideal angle measurement provided in an embodiment of the present invention;

[0046] Figure 2 A schematic diagram of angle measurement considering the influence of installation errors provided in an embodiment of the present invention;

[0047] Figure 3 A flowchart illustrating a method for correcting angle measurement errors provided in an embodiment of the present invention;

[0048] Figure 4 A flowchart illustrating the process of determining the parameter values ​​of the rotation correction parameters provided in this embodiment of the invention;

[0049] Figure 5 A simplified quadrilateral diagram of the axle structure and sensor bracket structure provided in the embodiments of the present invention;

[0050] Figure 6 A simplified overall measurement structure plan view provided for an embodiment of the present invention;

[0051] Figure 7 This is a schematic diagram of a device for correcting angle measurement errors provided in an embodiment of the present invention. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] Vehicle steering angle sensors are typically installed on one side of the steering axle (e.g., the steering angle sensor is usually installed on one side of the axle, such as the left side, and the measured value of the steering angle sensor is the wheel steering angle). When using the steering angle sensor to measure the steering angle, a parallelogram-shaped mounting bracket structure is generally used. In this case, the rotation angle of the steering angle sensor is equal to the rotation angle of the wheel kingpin. Thus, by measuring the rotation angle of the steering angle sensor, the rotation angle of the wheel kingpin is determined, thereby realizing the wheel steering angle measurement.

[0054] However, in existing angle measurement solutions, due to quality control issues at the factory and long-term use, the mounting bracket may deform, causing the rotation angle of the angle sensor and the rotation angle of the wheel kingpin to no longer conform to the ideal parallelogram relationship. That is, the angle value measured by the angle sensor is no longer equal to the kingpin rotation angle. This results in a difference between the angle measured by the sensor and the actual wheel angle, leading to low accuracy in angle measurement.

[0055] To address this issue, this invention provides a method and apparatus for correcting steering angle measurement errors. In this invention, after acquiring the initial steering angle value measured by the steering angle sensor, the initial steering angle value is corrected based on a steering angle correction rule to obtain a corrected steering angle value. Since the steering angle correction rule includes predetermined steering angle correction parameter values, these values ​​are selected from candidate values ​​based on the correspondence between historical left and right steering angle measurements and theoretical left and right steering angle values ​​determined in advance based on the current vehicle's steering angle spatial geometry. This means that the selection of steering angle correction parameter values ​​considers the current vehicle's steering angle spatial geometry, resulting in a more accurate selection that better reflects the current vehicle condition. Consequently, the accuracy of the selected parameter values ​​is higher, leading to higher accuracy when correcting steering angles based on these parameter values.

[0056] Based on the above, this invention provides a method for correcting steering angle measurement errors, used for vehicle steering angle correction. In practical applications, compared to installing steering angle sensors on only one side, this invention installs steering angle sensors on both the left and right wheels, such as steering angle encoders, axle height sensors, and other sensing elements capable of measuring rotation angles, allowing for simultaneous and accurate measurement of the steering angles of both wheels.

[0057] like Figure 1 As shown, 1 and 2 represent the left and right wheels, and 3 and 4 represent the steering angle sensors installed on the left and right sides, i.e., the left and right steering angle sensors. Ideal sensor installation ensures that the kingpin and sensor nodes form an ideal parallelogram, with a 1:1 ratio between opposite sides' swing angles. This means that, ignoring the kingpin's inclination angle, the steering angle sensor's measurement value matches the kingpin's rotation angle, achieving accurate steering angle measurement.

[0058] However, in practical applications, due to installation errors or long-term use, the quadrilateral formed by the sensor mounting nodes may twist and shift to some extent, causing deformation of the ideal parallelogram. This results in the swing angle of opposite sides (i.e., the rotation angle value measured by the angle sensor and the rotation angle of the kingpin; the rotation angle of the left kingpin is referenced). Figure 1In the left-side measuring quadrilateral, the rotation angle of the vertical line connected to the sensor quadrilateral node connected to the left wheel (similar to the right-side kingpin rotation angle) no longer satisfies a 1:1 ratio. That is, when the kingpin inclination angle is ignored, the sensor reading is not equal to the kingpin rotation angle, introducing an error at the measurement end. See details... Figure 2 .

[0059] To address the problem of angle measurement error, one embodiment of the present invention provides a method for correcting angle measurement error, referring to... Figure 3 It can include:

[0060] S11. Obtain the initial value of the rotation angle measured by the rotation angle sensor.

[0061] The corner sensors include a left corner sensor and a right corner sensor installed on the vehicle where the corner sensors are located; the initial corner values ​​include an initial left corner value and an initial right corner value.

[0062] When corner measurement correction is required, the initial corner value measured by the corner sensor is obtained.

[0063] S12, Obtain the corner correction rules.

[0064] The angle correction rule is a mapping relationship between the initial angle value and the angle correction value.

[0065] The cornering correction rule includes predetermined cornering correction parameter values. The cornering correction parameter values ​​are selected from the candidate values ​​of the cornering correction parameter based on the correspondence between historical left and right cornering measurement values ​​and theoretical left and right cornering measurement values ​​determined in advance based on the cornering spatial geometry of the current vehicle, and the candidate value with the smallest measurement error.

[0066] In this embodiment, the angle correction parameter value can be determined offline, and the angle correction parameter value can be updated every certain period of time.

[0067] S13. Using the aforementioned angle correction rule, the initial angle value is corrected to obtain the angle correction value.

[0068] Specifically, after obtaining the corner correction rule, the initial corner value can be corrected using the corner correction rule to obtain the corner correction value.

[0069] In this embodiment, after obtaining the initial angle value measured by the angle sensor, the initial angle value is corrected based on the angle correction rule to obtain the angle correction value. Since the angle correction rule includes the parameter values ​​of the predetermined angle correction parameters, the parameter values ​​of the angle correction parameters are selected from the candidate values ​​of the angle correction parameters based on the correspondence between historical left and right angle measurement values ​​and the theoretical values ​​of left and right angle measurement determined in advance based on the current vehicle's angle spatial geometry. That is, when selecting the parameter values ​​of the angle correction parameters, the current vehicle's angle spatial geometry is considered, and the selected parameter values ​​are more consistent with the current vehicle conditions, thus making the accuracy of the selected parameter values ​​higher. Therefore, the accuracy of angle correction based on these parameter values ​​is higher.

[0070] The above embodiments mentioned the parameter values ​​required for angle correction. The process of determining these parameter values ​​will now be described. (Refer to...) Figure 4 The process of determining the values ​​of the angle correction parameters includes:

[0071] S21. Obtain the correspondence between the theoretical values ​​of the left and right turning angles, which are pre-determined based on the current vehicle's turning angle spatial geometry.

[0072] Specifically, refer to Figure 2 The spatial geometric relationships between the steering trapezoid, the left-side measuring quadrilateral, and the right-side measuring quadrilateral jointly determine the correspondence between the measurement values ​​of the left and right steering angle sensors. That is, when the mechanical structure of the axle and the sensor mounting structure are determined, the correspondence between the left and right measurement values ​​is uniquely determined.

[0073] Through spatial or simplified geometric relationships, the theoretical functional relationship between the measured values ​​on the left and right can be obtained:

[0074] θ R -θ R0 =f(θ) L -θ L0 )

[0075] in:

[0076] θ L0 This represents the zero-position error of the left-side sensor, which is the actual rotation angle measurement value of the left-side rotation angle sensor when the wheel is aligned.

[0077] θ R0 This represents the zero-position error of the right-side sensor, which is the actual rotation angle measurement value of the right-side rotation angle sensor when the wheel is aligned.

[0078] f is a function related to the mechanical structure and spatial geometry.

[0079] f can be solved based on spatial solid geometry relationships. Optionally, the function can be appropriately simplified by ignoring the kingpin inclination angle and the spatial interlacing relationship between the axle and the bracket, thus simplifying the spatial solid geometry problem into a plane geometry problem. For example... Figure 5 As shown, for any quadrilateral, the side lengths and one interior angle can uniquely determine a convex quadrilateral. The relationship between opposite sides and angles of a quadrilateral, i.e., the relationship between the left side angle (∠G'AG) and the right side angle (∠F'EF), can be represented by the side lengths and one interior angle. The axle structure and sensor bracket structure can be simplified as follows: Figure 5 The quadrilateral AEFG is shown. In quadrilateral AEFG, vertices A and E are fixed, and AG and EF can be rotated around vertices A and E respectively. The correspondence between ∠G'AG and ∠F'EF is as follows:

[0080] Let AE=l1, EF=l2, FG=l3, GA=l4, ∠GAE=θ L ∠FEA=θ R ∠G'AG=Δθ L ∠F'EF=Δθ R Then we have:

[0081]

[0082] in:

[0083]

[0084] Figure 6 The simplified overall measurement structure plan is shown in the diagram. In the diagram, quadrilateral ABCD represents the turning trapezoid, quadrilateral AEFG represents the left-side measurement quadrilateral, and quadrilateral HBJI represents the right-side measurement quadrilateral. Through the above angle transfer relationships, the theoretical values ​​of the left and right turning angle measurements can be obtained.

[0085] Let AE=ALl1, EF=ALl2, FG=ALl3, GA=ALl4, ∠GAE=ALθ L ∠FEA=ALθ R ;

[0086] AB=Bl1, BC=Bl2, CD=Bl3, DA=Bl4, ∠DAB=Bθ L ∠CBA=Bθ R ;

[0087] HB=ARl1, BJ=ARl2, JI=ARl3, IH=ARl4, ∠IHB=ARθ L ∠JBH=ARθ R ;

[0088] The swing angle ΔALθ of AG LThe swing angle of EF is ΔALθ R The swing angle of AD is ΔBθ L The swing angle of BC is ΔBθ R The swing angle of HI is ΔBθ R The swing angle of BJ is ΔARθ R .

[0089] Based on geometric relationships, we can obtain:

[0090] Formula 1:

[0091]

[0092] Formula 2:

[0093]

[0094] Formula 3:

[0095]

[0096] Formula 4:

[0097]

[0098] Formula 5:

[0099]

[0100] Formula 6:

[0101]

[0102] Point A of the left sensor bracket is fixed to the left wheel kingpin. The change in ∠GAE (the swing angle of AG) is ΔALθ. L Equal to the change in ∠DAB (the angle of AD's swing) ΔBθ L ,have to:

[0103] Formula 7:

[0104] ΔALθ L =ΔBθ L

[0105] Point B of the right-side sensor bracket is fixed to the right wheel kingpin. The change in ∠JBH (the swing angle of JB) is ΔARθ. R Equal to the change in ∠CBA (the angle of CB's swing) ΔBθ R ,have to:

[0106] Formula 8:

[0107] ΔARθ R =ΔBθ R

[0108] Combining equations 1 to 8, we can obtain the following equation (1):

[0109] ΔARθ L =f(ΔALθ) R ,ALl1,ALl2,ALl3,ALl4,Alθ L ,Bl1,Bl2,Bl3,Bl4,Bθ L ,ARl1,ARl2,ARl3,ARl4,ARθ L Equation (1) represents the correspondence between the theoretical values ​​of the left and right turning angle measurements. Where ΔARθ L The theoretical value for the right turn angle is ΔALθ. R The left turn angle is the theoretical value measured; the other parameters are turn angle correction parameters.

[0110] S22. Determine the candidate values ​​for the angle correction parameter.

[0111] In practical applications, step S22 may include:

[0112] 1) Obtain the theoretical value of the angle correction parameter.

[0113] The angle correction parameters include the parameters of the left and right sensor mounting brackets and the steering trapezoidal parameters.

[0114] The parameters for the left and right sensor mounting brackets include:

[0115] ALl1,ALl2,ALl3,ALl4,ALθ L ,ALl1,ARl2,ARl3,ARl4,ARθ L .

[0116] Steering trapezoidal parameters include: Bl1, Bl2, Bl3, Bl4, Bθ L .

[0117] In practical applications, Bl1, Bl2, Bl3, Bl4, and Bθ can be determined based on the steering axle structural drawings. L The theoretical values ​​are determined based on the sensor mounting bracket design drawings, specifically ALl1, ALl2, ALl3, ALl4, and ALθ. L ,ARl1,ARl2,ARl3,ARl4,ARθ L The theoretical value.

[0118] 2) Based on the installation accuracy of the left and right sensor mounting brackets and the steering trapezoid, determine the parameter traversal range of the steering angle correction parameters.

[0119] Specifically, during the installation of the left and right sensor mounting brackets and the steering trapezoidal mounting process, there is a certain installation accuracy, such as ±1. The installation accuracy can be different for different steering angle correction parameters. Therefore, the parameter traversal range of the steering angle correction parameters can be determined based on the installation accuracy. For example, if the installation accuracy is ±1, the parameter traversal range of the steering angle correction parameters is within the range of the theoretical value ±1, that is, the parameter traversal range is (theoretical value - 1) - (theoretical value + 1).

[0120] 3) Determine the candidate values ​​of the theoretical value within the range of the parameter traversal.

[0121] Specifically, after determining the theoretical value and the parameter traversal range, several values ​​can be selected within the parameter traversal range as candidate values.

[0122] It should be noted that since there are multiple corner correction parameters, multiple corner correction parameter sets can be determined based on the candidate values ​​of each corner correction parameter. Each corner correction parameter set includes one value of each corner correction parameter.

[0123] S23. Obtain historical left and right corner measurement values.

[0124] Specifically, multiple sets of historical left-turn angle measurements are obtained, as well as the corresponding historical right-turn angle measurements for each set of historical left-turn angle measurements.

[0125] The historical left and right turn angle measurements include the historical left turn angle measurement value {θ}. L1 ,θ L2 ,……θ Ln} and the historical right turn measurement value {θ} corresponding to the historical left turn measurement value. R1 ,θ R2 ,……θ Rn}

[0126] Historical left and right corner measurements can be obtained offline, such as obtaining left and right corner measurements for one month in the past.

[0127] S24. Based on the correspondence between the historical left and right angle measurement values ​​and the theoretical values ​​of the left and right angle measurement, perform an iterative optimization operation on the candidate values ​​of the angle correction parameter to obtain the candidate values ​​of the angle correction parameter with the smallest measurement error, and use them as the parameter values ​​of the angle correction parameter.

[0128] Specifically, in the above embodiments, multiple sets of corner correction parameters are obtained, and the optimal set of corner correction parameters needs to be selected from them.

[0129] In practical applications, step S24 may include:

[0130] 1) For the candidate values ​​of the turning angle correction parameter, calculate the estimated value of the historical right turning angle corresponding to the historical left turning angle measurement value based on the correspondence between the historical left turning angle measurement value and the theoretical values ​​of the left and right turning angle measurements.

[0131] Specifically, the calculation formula for obtaining the historical right turn angle estimate corresponding to the historical left turn angle measurement value is obtained. The calculation formula includes the correspondence between the historical left turn angle measurement value, the turn angle correction parameter, and the historical right turn angle measurement value.

[0132] In practical applications, due to installation errors, the sensor measurements may have a small initial value when the wheel is aligned. Let's assume the initial measurement value of the left steering angle sensor is θ. L0 The initial measurement value of the right-side angle sensor is θ. R0 During actual rotation, the readings of the left and right rotation angle sensors are θ and θ, respectively. L θ R Then: the initial value of the right turn angle is ΔARθ' L =θ R -θ R0 Initial value of left turn angle ΔALθ′ R =θ L -θ L0 Therefore, according to equation (1) above, the estimated value of the measured right-side corner sensor is... It can be represented by the left-side angle sensor reading (measured value of the left-side angle sensor), the sensor zero-position error, and the structural geometry:

[0133]

[0134] Using this formula, for each set of candidate values ​​for the corner correction parameters, the estimated value of the historical right corner corresponding to the historical left corner measurement can be calculated.

[0135] It should be noted that this embodiment does not require specific installation location or fixing method for the sensor. When the installation location changes, the above theoretical formula needs to be modified accordingly based on the actual installation geometry.

[0136] 2) Calculate the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value.

[0137] In practical applications, the difference between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value can be calculated. Then, the sum of squares of the differences is calculated to obtain the measurement error. n is the number of angle measurements, and the sum of the squares obtained is the measurement error.

[0138] In addition to calculating the sum of squares, the sum of absolute values ​​of the differences can also be calculated, and the sum of absolute values ​​of the differences can be used as the measurement error.

[0139] 3) Select the historical right-turn angle estimate with the smallest measurement error, and determine the candidate values ​​of the angle correction parameter corresponding to the selected historical right-turn angle estimate.

[0140] When the geometric parameters perfectly match the spatial relationship, the error is zero. Since the kingpin inclination angle is ignored during the calculation, and the sensor measurements have some noise, the error is not absolutely zero. However, the smaller the error, the closer the parameters in equation (1) are to the actual installation dimensions. Therefore, n sets of measurements ({θ...) are taken. R1 ,θ R2 ,……θ Rn}, {θ L1 ,θ L2 ,……θ Ln When a certain set of parameters: (

[0142] θ L0 ,ALl1,ALl2,ALl3,ALl4,ALθ L ,Bl1,Bl2,Bl3,Bl4,Bθ L ,ARl1,ARl2,ARl3,ARl4,ARθ L ,θR0)

[0143] make The minimum value of this set of parameters can characterize the actual installation size and position, which is also the candidate value of the optimal corner correction parameter. This candidate value of the corner correction parameter can be used as the parameter value of the corner correction parameter.

[0144] Based on this embodiment, step S13 may include:

[0145] Obtain the angle correction formula and substitute the initial angle value into the angle correction formula to obtain the angle correction value.

[0146] Specifically, the parameter values ​​for the angle correction parameters are determined through this embodiment, namely the lengths of the four sides of the left sensor bracket and the left bottom corners ALl1, ALl2, ALl3, ALl4, and ALθ. L The lengths of the four sides of the right-side sensor bracket and the left bottom corners ARl1, ARl2, ARl3, ARl4, and ALθ L The corner correction rules can be determined as follows:

[0147] The corner correction formula includes a left corner correction formula and a right corner correction formula; the left corner correction formula is:

[0148] θ′ left =gl (θ left ,ALl1,All2,ARl3,All4,ALθ L )

[0149] Among them, g l Represents the function, θ' left θ is the left turn angle correction value. left The initial values ​​for the left turn angle are ALl1, ALl2, ALl3, ALl4, and ALθ. L These are the parameters for corner correction;

[0150] The formula for correcting the right turn angle is:

[0151] θ′ right =g R (θ right , ARl1, ARl2, ARl3, ARl4, ARθ L )

[0152] Among them, g R Represents the function, θ' right θ is the right turn correction value. right The initial values ​​for the right turn angle are: ARl1, ARl2, ARl3, ARl4, ARθ. L These are the parameters for corner correction.

[0153] In practical applications, different steering trapezoid correction rules exist. For example, a steering angle correction rule can be specifically expressed as follows:

[0154] Where, θ' left =ΔALθ L θ left =ΔALθ′ R ,θ' right =ΔARθ R θ right =ΔARθ′ L Left turn correction rules:

[0155]

[0156] in:

[0157]

[0158] Right turn correction rules:

[0159]

[0160] in:

[0161]

[0162] Therefore, after obtaining the initial value of the turning angle, the left and right turning angles can be corrected according to the above formula to obtain the turning angle correction value.

[0163] In this embodiment, the zero-point calibration of the sensors can be achieved by measuring the values ​​of the left and right wheel angle sensors, and an effective conversion relationship between the measured angle and the actual angle can be obtained. Compared with the existing technology that requires a professional four-wheel alignment machine for zero-point calibration at the factory (the vehicle undergoes four-wheel alignment at the factory to determine the actual wheel zero-point position, and the value of the angle sensor at this time is read as the zero-point offset, which is corrected by mechanical zero-point adjustment or software correction; four-wheel alignment requires a professional four-wheel alignment machine and cannot achieve flexible correction of the angle measurement value throughout the entire operating life of the vehicle), in this embodiment, after obtaining the actual parameters, Bl4 represents the actual length of the tie rod, and Bθ L Bθ represents the left bottom angle of the turning trapezoid. L Representing the right bottom angle of the steering trapezoid, the theoretical bottom angle for zero toe-in design is known to be Bθ. L0 Bθ R0 Then the current left anterior bundle α L =Bθ L0 -Bθ L The current right anterior alpha R =Bθ R0 -Bθ R Adjusting the length of the tie rod Bl4 to make the left and right toe angles consistent with the designed toe angles achieves four-wheel alignment. No professional instruments are required, and the vehicle can be periodically aligned and the steering angle can be measured and corrected.

[0164] Optionally, based on the above-described embodiment of the method for correcting angle measurement errors, another embodiment of the present invention provides a device for correcting angle measurement errors, referring to... Figure 7 It can include:

[0165] The initial value acquisition module 11 is used to acquire the initial angle value measured by the angle sensor; the angle sensor includes a left angle sensor and a right angle sensor installed on the vehicle where the angle sensor is located; the initial angle value includes the initial left angle and the initial right angle.

[0166] The rule acquisition module 12 is used to acquire the corner correction rule, which is a mapping relationship between the initial corner value and the corner correction value. The corner correction rule includes the parameter values ​​of the predetermined corner correction parameter. The parameter values ​​of the corner correction parameter are selected from the candidate values ​​of the corner correction parameter based on the correspondence between the historical left and right corner measurement values ​​and the theoretical values ​​of the left and right corner measurement determined in advance based on the corner spatial geometry of the current vehicle, and the candidate value with the smallest measurement error.

[0167] The corner correction module 13 is used to correct the initial corner value using the corner correction rule to obtain the corner correction value.

[0168] Furthermore, it also includes a parameter determination module, including:

[0169] The relationship acquisition submodule is used to acquire the correspondence between the theoretical values ​​of the left and right turning angle measurements, which are pre-determined based on the current vehicle's turning angle spatial geometry.

[0170] The candidate value determination submodule is used to determine the candidate values ​​of the angle correction parameter;

[0171] The measurement value acquisition submodule is used to acquire historical left and right corner measurement values; the historical left and right corner measurement values ​​include historical left corner measurement values ​​and historical right corner measurement values ​​corresponding to the historical left corner measurement values;

[0172] The parameter value determination submodule is used to perform an iterative optimization operation on the candidate values ​​of the angle correction parameter based on the correspondence between the historical left and right angle measurement values ​​and the theoretical values ​​of the left and right angle measurement, so as to obtain the candidate value of the angle correction parameter with the smallest measurement error, and use it as the parameter value of the angle correction parameter.

[0173] Furthermore, the candidate value determination submodule is specifically used for:

[0174] The theoretical value of the steering angle correction parameter is obtained. The steering angle correction parameter includes the left and right sensor mounting bracket parameters and the steering trapezoidal parameter. Based on the installation accuracy of the left and right sensor mounting brackets and the steering trapezoidal parameter, the parameter traversal range of the steering angle correction parameter is determined, and the candidate value of the theoretical value within the parameter traversal range is determined.

[0175] Furthermore, the measurement value acquisition submodule is specifically used for:

[0176] Obtain multiple sets of historical left-turn angle measurements, and obtain the historical right-turn angle measurements corresponding to each set of historical left-turn angle measurements.

[0177] Furthermore, the parameter value determination submodule is specifically used for:

[0178] For the candidate values ​​of the turning angle correction parameter, the estimated value of the historical right turning angle corresponding to the historical left turning angle measurement value is calculated based on the correspondence between the historical left turning angle measurement value and the theoretical values ​​of the left and right turning angle measurements.

[0179] Calculate the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value;

[0180] The historical right-turn angle estimates with the smallest measurement error are selected, and candidate values ​​for the angle correction parameters corresponding to the selected historical right-turn angle estimates are determined.

[0181] Furthermore, the parameter value determination submodule, when calculating the estimated historical right turn angle corresponding to the historical left turn angle measurement value based on the correspondence between the historical left turn angle measurement value and the theoretical values ​​of the left and right turn angle measurements, is specifically used for:

[0182] A calculation formula is used to obtain the estimated historical right turn value corresponding to the historical left turn angle measurement value. The calculation formula includes the correspondence between the historical left turn angle measurement value, the angle correction parameter, and the historical right turn angle measurement value.

[0183] Furthermore, when the parameter value determination submodule calculates the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value, it is specifically used for:

[0184] Calculate the difference between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value, and calculate the sum of squares or the sum of absolute values ​​of the differences, wherein the sum of squares or the sum of absolute values ​​of the differences are used as the measurement error.

[0185] Furthermore, the corner correction module 13 is specifically used for:

[0186] Obtain the angle correction formula and substitute the initial angle value into the angle correction formula to obtain the angle correction value.

[0187] Furthermore, the turning angle correction formula includes a left turning angle correction formula and a right turning angle correction formula; the left turning angle correction formula is:

[0188] θ′ left =g l (θ left ,ALl1,ALl2,ALl3,ALl4,ALθ L );

[0189] Among them, g l Represents the function, θ' left θ is the left turn angle correction value. left The initial values ​​for the left turn angle are ALl1, ALl2, ALl3, ALl4, and ALθ. L These are the parameters for corner correction;

[0190] The formula for correcting the right turn angle is:

[0191] θ′ right =g R (θ right , ARl1, ARl2, ARL3, ARl4, ARθ L )

[0192] Among them, g RRepresents the function, θ' right θ is the right turn correction value. right The initial values ​​for the right turn angle are: ARl1, ARl2, ARl3, ARl4, ARθ. L These are the parameters for corner correction.

[0193] In this embodiment, after obtaining the initial angle value measured by the angle sensor, the initial angle value is corrected based on the angle correction rule to obtain the angle correction value. Since the angle correction rule includes the parameter values ​​of the predetermined angle correction parameters, the parameter values ​​of the angle correction parameters are selected from the candidate values ​​of the angle correction parameters based on the correspondence between historical left and right angle measurement values ​​and the theoretical values ​​of left and right angle measurement determined in advance based on the current vehicle's angle spatial geometry. That is, when selecting the parameter values ​​of the angle correction parameters, the current vehicle's angle spatial geometry is considered, and the selected parameter values ​​are more consistent with the current vehicle conditions, thus making the accuracy of the selected parameter values ​​higher. Therefore, the accuracy of angle correction based on these parameter values ​​is higher.

[0194] It should be noted that the working process of each module and sub-module in this embodiment is described in the corresponding descriptions in the above embodiments, and will not be repeated here.

[0195] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for correcting angle measurement errors, characterized in that, include: The initial value of the turning angle is obtained from the measurement of the turning angle sensor; the turning angle sensor includes a left turning angle sensor and a right turning angle sensor installed on the vehicle where the turning angle sensor is located; the initial value of the turning angle includes the initial value of the left turning angle and the initial value of the right turning angle; Obtain the corner correction rule, which is a mapping relationship between the initial corner value and the corner correction value. The corner correction rule includes the parameter values ​​of the predetermined corner correction parameters. The parameter values ​​of the corner correction parameters are selected from the candidate values ​​of the corner correction parameters based on the correspondence between the historical left and right corner measurement values ​​and the theoretical left and right corner measurement values ​​determined in advance based on the corner spatial geometry of the current vehicle, and the candidate value with the smallest measurement error. The initial angle value is corrected using the aforementioned angle correction rule to obtain the angle correction value; The process of determining the parameter value of the rotation angle correction parameter includes: Obtain the correspondence between the theoretical values ​​of the left and right turning angles, which are pre-determined based on the current vehicle's turning angle spatial geometry. Obtain the theoretical values ​​of the steering angle correction parameters; the steering angle correction parameters include the parameters of the left and right sensor mounting brackets and the steering trapezoidal parameters; Based on the installation accuracy of the left and right sensor mounting brackets and the steering trapezoid, the parameter traversal range of the steering angle correction parameters is determined. Determine candidate values ​​for the theoretical value within the range of the parameter traversal; Obtain historical left and right corner measurement values; the historical left and right corner measurement values ​​include historical left corner measurement values ​​and historical right corner measurement values ​​corresponding to the historical left corner measurement values; Based on the correspondence between the historical left and right turning angle measurements and the theoretical left and right turning angle measurements, an iterative optimization operation is performed on the candidate values ​​of the turning angle correction parameter to obtain the candidate values ​​of the turning angle correction parameter with the smallest measurement error, and these candidate values ​​are used as the parameter values ​​of the turning angle correction parameter.

2. The correction method according to claim 1, characterized in that, Obtain historical left and right corner measurements, including: Obtain multiple sets of historical left-turn angle measurements, and obtain the historical right-turn angle measurements corresponding to each set of historical left-turn angle measurements.

3. The correction method according to claim 1, characterized in that, Based on the correspondence between the historical left and right turning angle measurements and the theoretical left and right turning angle measurements, an iterative optimization operation is performed on the candidate values ​​of the turning angle correction parameter to obtain the candidate values ​​of the turning angle correction parameter with the minimum measurement error, including: For the candidate values ​​of the turning angle correction parameter, the estimated value of the historical right turning angle corresponding to the historical left turning angle measurement value is calculated based on the correspondence between the historical left turning angle measurement value and the theoretical values ​​of the left and right turning angle measurements. Calculate the measurement error between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value; The historical right-turn angle estimates with the smallest measurement error are selected, and candidate values ​​for the angle correction parameters corresponding to the selected historical right-turn angle estimates are determined.

4. The correction method according to claim 3, characterized in that, Based on the correspondence between the historical left-turn angle measurements and the theoretical values ​​of the left and right turn angle measurements, the estimated historical right-turn angle corresponding to the historical left-turn angle measurements is calculated, including: A calculation formula is used to obtain the estimated historical right turn value corresponding to the historical left turn angle measurement value. The calculation formula includes the correspondence between the historical left turn angle measurement value, the angle correction parameter, and the historical right turn angle measurement value.

5. The correction method according to claim 3, characterized in that, The measurement error between the historical right turn measurement and the historical right turn estimate corresponding to the historical left turn measurement is calculated, including: Calculate the difference between the historical right turn measurement value and the historical right turn estimate corresponding to the historical left turn measurement value; Calculate the sum of squares or the sum of absolute values ​​of the differences, wherein the sum of squares or the sum of absolute values ​​of the differences is taken as the measurement error.

6. The correction method according to claim 1, characterized in that, Using the aforementioned angle correction rule, the initial angle value is corrected to obtain the angle correction value, including: Obtain the angle correction formula and substitute the initial angle value into the angle correction formula to obtain the angle correction value.

7. The correction method according to claim 6, characterized in that, The corner correction formula includes a left corner correction formula and a right corner correction formula; the left corner correction formula is: ； in, Represents a function, This is the left turn correction value. This is the initial value for the left turn. These are the parameters for corner correction; The formula for correcting the right turn angle is: in, Represents a function, This is the right turn correction value. This is the initial value for the right turn; These are the parameters for corner correction.

8. A device for correcting angle measurement errors, characterized in that, include: An initial value acquisition module is used to acquire the initial angle value measured by the angle sensor; the angle sensor includes a left angle sensor and a right angle sensor installed on the vehicle where the angle sensor is located; the initial angle value includes the initial left angle and the initial right angle. The rule acquisition module is used to acquire the corner correction rule, which is a mapping relationship between the initial corner value and the corner correction value. The corner correction rule includes the parameter values ​​of the pre-determined corner correction parameters. The parameter values ​​of the corner correction parameters are selected from the candidate values ​​of the corner correction parameters based on the correspondence between historical left and right corner measurement values ​​and the theoretical values ​​of left and right corner measurement determined in advance based on the corner spatial geometry of the current vehicle, and the candidate value with the smallest measurement error. Angle correction module is used to correct the initial angle value using the angle correction rule to obtain the angle correction value; The parameter determination module includes: The relationship acquisition submodule is used to acquire the correspondence between the theoretical values ​​of the left and right turning angle measurements, which are pre-determined based on the current vehicle's turning angle spatial geometry. The candidate value determination submodule is used to obtain the theoretical value of the steering angle correction parameter, which includes the left and right sensor mounting bracket parameters and the steering trapezoidal parameters. Based on the installation accuracy of the left and right sensor mounting brackets and the steering trapezoidal parameters, the parameter traversal range of the steering angle correction parameter is determined, and the candidate value of the theoretical value within the parameter traversal range is determined. The measurement value acquisition submodule is used to acquire historical left and right corner measurement values; the historical left and right corner measurement values ​​include historical left corner measurement values ​​and historical right corner measurement values ​​corresponding to the historical left corner measurement values; The parameter value determination submodule is used to perform an iterative optimization operation on the candidate values ​​of the angle correction parameter based on the correspondence between the historical left and right angle measurement values ​​and the theoretical values ​​of the left and right angle measurement, so as to obtain the candidate value of the angle correction parameter with the smallest measurement error, and use it as the parameter value of the angle correction parameter.

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