Calibration method and device of wheel type odometer and storage medium

Abstract

The invention discloses a wheel type speedometer calibration method and device and a storage medium, and the wheel type speedometer calibration method comprises the steps: controlling a mobile device to run along a preset path, and obtaining a rotation angle sensed by a scene sensor and a rotation angle sensed by a wheel type speedometer recorded in a current driving stage, resolving to obtain the steering wheel zero offset corresponding to the wheel type odometer in the current driving stage; acquiring a motion offset sensed by a scene sensor and a motion offset sensed by a wheel type odometer, which are recorded in a driving stage when the steering wheel zero offset is smaller than a preset zero offset threshold value, and acquiring an external parameter rotation matrix between the wheel type odometer and the scene sensor; according to the method, the steering wheel radius corresponding to the wheel type speedometer is calculated by combining the obtained motion offset sensed by the scene sensor, the motion offset sensed by the wheel type speedometer and the external parameter rotation matrix, and the more accurate steering wheel radius is calculated by using the sensed data recorded after the steering wheel zero offset is stable, so that the calibration accuracy of the wheel type speedometer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of mobile robot calibration, and in particular to a calibration method, device and storage medium for a wheel odometer. Background Art

[0002] For high-precision robots (such as automated guided vehicles or unmanned guided vehicles), steering wheel calibration is a very important part. Among them, steering wheel parameter calibration is one of the important factors affecting robot movement and terminal accuracy. For high-precision robots, the higher the working accuracy requirements, the higher the requirements for steering wheel parameter calibration accuracy.

[0003] In traditional calibration methods, calibration operations are usually completed manually, and actual parameter values ​​are obtained through visual observation and measurement. However, calibration based solely on visual observation is prone to large measurement errors and low calibration efficiency, making it difficult to meet the needs of high-precision control scenarios. Summary of the invention

[0004] In order to solve the above technical problems, the present application at least provides a calibration method, device and storage medium for a wheel odometer.

[0005] The first aspect of the present application provides a calibration method for a wheel odometer, in which a mobile device is deployed with a wheel odometer and a scene sensor for collecting scene spatial information, the method comprising: controlling the mobile device to travel along a preset path, and obtaining a rotation angle sensed by the scene sensor and a rotation angle sensed by the wheel odometer recorded in a current driving stage; wherein the preset path is composed of straight road sections corresponding to a plurality of driving stages respectively; taking the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer as a constraint condition, solving to obtain a steering wheel zero bias corresponding to the wheel odometer in the current driving stage; obtaining a motion offset sensed by the scene sensor and a motion offset sensed by the wheel odometer recorded in a driving stage in which the steering wheel zero bias is less than a preset zero bias threshold, and obtaining an extrinsic rotation matrix between the wheel odometer and the scene sensor; combining the obtained motion offset sensed by the scene sensor, the acquired motion offset sensed by the wheel odometer, and the extrinsic rotation matrix, solving to obtain a steering wheel radius corresponding to the wheel odometer.

[0006] In one embodiment, before obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage when the steering wheel zero deviation is less than the preset zero deviation threshold, the method also includes: if it is detected that the steering wheel zero deviation in the current driving stage is less than the preset zero deviation threshold, the number of consecutive cumulative stages is increased by one; if it is detected that the steering wheel zero deviation in the current driving stage is not less than the preset zero deviation threshold, the number of consecutive cumulative stages is set to zero; in response to the number of consecutive cumulative stages being greater than or equal to the preset number threshold, the step of obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage when the steering wheel zero deviation is less than the preset zero deviation threshold is executed.

[0007] In one embodiment, if it is detected that the steering wheel zero deviation in the current driving stage is less than a preset zero deviation threshold, the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the current driving stage are also cached in the candidate data set; if it is detected that the steering wheel zero deviation in the current driving stage is not less than the preset zero deviation threshold, the candidate data set is also cleared; in response to the number of consecutive accumulated stages being greater than or equal to the preset number threshold, the step of obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero deviation is less than the preset zero deviation threshold is executed, including: obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in each driving stage in the candidate data set.

[0008] In one embodiment, the motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the extrinsic parameter rotation matrix are combined to obtain the steering wheel radius corresponding to the wheel odometer, including: combining the motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the extrinsic parameter rotation matrix obtained in each driving stage to respectively obtain the steering wheel radius corresponding to each driving stage; calculating the average value of the steering wheel radius corresponding to each driving stage to obtain the steering wheel radius corresponding to the wheel odometer.

[0009] In one embodiment, the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the extrinsic parameter rotation matrix are combined to calculate the steering wheel radius corresponding to the wheel odometer, including: taking the product of the motion offset perceived by the scene sensor and the extrinsic parameter rotation matrix and the motion offset perceived by the wheel odometer as a constraint condition to calculate the steering wheel radius corresponding to the wheel odometer.

[0010] In one embodiment, the method also includes: obtaining the steering wheel zero bias calculated in the previous driving stage; based on the steering wheel zero bias calculated in the previous driving stage, calculating the zero bias compensation value corresponding to the current driving stage; and using the zero bias compensation value to control the driving of the mobile device in the current driving stage.

[0011] In one embodiment, the method also includes: if it is detected that the steering wheel zero bias in the current driving stage is less than a preset zero bias threshold, the number of consecutive cumulative stages is increased by one; if it is detected that the steering wheel zero bias in the current driving stage is not less than the preset zero bias threshold, the number of consecutive cumulative stages is set to zero; in response to the number of consecutive cumulative stages being greater than or equal to the preset number threshold, the current zero bias compensation value is used as the steering wheel zero bias calibration value.

[0012] In one embodiment, the scene sensor includes a laser sensor; obtaining the rotation angle perceived by the scene sensor recorded in the current driving stage, including: obtaining point cloud data collected by the laser sensor at the start time of driving and the point cloud data collected at the end time of driving in the current driving stage; matching the point cloud data collected at the start time of driving with the point cloud data collected at the end time of driving to obtain the rotation angle perceived by the laser sensor.

[0013] According to a second aspect of the present application, there is provided a calibration device for a wheel odometer, the device comprising: an angle acquisition module, used to control a mobile device to travel along a preset path, and to obtain the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer recorded in the current driving stage; wherein the preset path is composed of straight road sections corresponding to a plurality of driving stages; a zero bias solution module, used to solve the steering wheel zero bias corresponding to the wheel odometer in the current driving stage with the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer being equal as a constraint condition; an offset acquisition module, used to obtain the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero bias is less than a preset zero bias threshold, and to obtain an external parameter rotation matrix between the wheel odometer and the scene sensor; a steering wheel radius solution module, used to solve the steering wheel radius corresponding to the wheel odometer by combining the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the external parameter rotation matrix.

[0014] A third aspect of the present application provides a mobile device, including a memory and a processor, wherein the processor is used to execute program instructions stored in the memory to implement the calibration method of the wheel odometer.

[0015] A fourth aspect of the present application provides a computer-readable storage medium having program instructions stored thereon, which implement the calibration method of the above-mentioned wheel odometer when the program instructions are executed by a processor.

[0016] The above scheme controls the mobile device to travel along a preset path, and obtains the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer recorded in the current driving stage; takes the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer to be equal as a constraint condition, and solves to obtain the steering wheel zero bias corresponding to the wheel odometer in the current driving stage; obtains the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero bias is less than the preset zero bias threshold, and obtains the external parameter rotation matrix between the wheel odometer and the scene sensor to filter and obtain the perception data recorded after the steering wheel zero bias is stabilized; combines the obtained motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the external parameter rotation matrix to solve and obtain the steering wheel radius corresponding to the wheel odometer, and uses the perception data recorded after the steering wheel zero bias is stabilized to solve and obtain a more accurate steering wheel radius, thereby improving the accuracy of the wheel odometer calibration.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings herein are incorporated into the specification and constitute a part of the specification. These drawings illustrate embodiments consistent with the present application and are used together with the specification to illustrate the technical solution of the present application.

[0019] Figure 1 It is a schematic diagram of an implementation environment of a solution provided by an embodiment of the present application;

[0020] Figure 2 is a flow chart of a calibration method of a wheel odometer shown in an exemplary embodiment of the present application;

[0021] Figure 3 is a schematic diagram of a preset path shown in an exemplary embodiment of the present application;

[0022] Figure 4 is a schematic diagram of the movement of a single steering wheel shown in an exemplary embodiment of the present application;

[0023] Figure 5 is a block diagram of a calibration device for a wheel odometer shown in an exemplary embodiment of the present application;

[0024] Figure 6 is a structural schematic diagram of a mobile device shown in an exemplary embodiment of the present application;

[0025] Figure 7 It is a schematic diagram of the structure of a computer-readable storage medium shown in an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0026] The scheme of the embodiment of the present application is described in detail below in conjunction with the drawings of the specification.

[0027] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures, interfaces, and technologies are provided to facilitate a thorough understanding of the present application.

[0028] The term "and / or" in this article is only an association information describing the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the previous and next associated objects are in an "or" relationship. In addition, "many" in this article means two or more than two. In addition, the term "at least one" in this article means any combination of at least two of any one or more of a plurality of, for example, including at least one of A, B, and C, can mean including any one or more elements selected from the set consisting of A, B, and C.

[0029] The following is an explanation of the calibration method of the wheel odometer provided in the embodiment of the present application.

[0030] Please refer to Figure 1 , which shows a schematic diagram of a solution implementation environment provided by an embodiment of the present application. The solution implementation environment may include a mobile device 110 and a server 120, and the mobile device 110 and the server 120 are connected to each other for communication.

[0031] The mobile device 110 may be an automatic guided vehicle, an unmanned transport vehicle, a sweeping robot, etc., but is not limited thereto.

[0032] Server 120 can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers. It can also be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (CDN), as well as big data and artificial intelligence platforms.

[0033] In one example, the server 120 sends an instruction to the mobile device 110 to travel along a preset path, and obtains data sensed by the scene sensors and the wheel odometer recorded during the driving phase of the mobile device 110 to solve the steering wheel zero bias, and selects the data sensed by the scene sensors and the wheel odometer for solving the steering wheel radius according to the steering wheel zero bias, and then solves the steering wheel radius. Of course, the server 120 can transmit the steering wheel zero bias and the steering wheel radius back to the mobile device 110 for calibration.

[0034] In one example, a related application for parameter calibration is installed and run in the mobile device 110, through which the mobile device 110 is controlled to travel along a preset path, and data sensed by the scene sensor and data sensed by the wheel odometer recorded during the driving phase of the mobile device 110 are obtained to solve the steering wheel zero bias, and the data sensed by the scene sensor and data sensed by the wheel odometer are selected for solving the steering wheel radius according to the steering wheel zero bias, so as to solve the steering wheel radius.

[0035] In the calibration method of the wheel odometer provided in the embodiment of the present application, the execution entity of each step can be the mobile device 110, such as the relevant application for parameter calibration installed and running in the mobile device 110, or the server 120, or the mobile device 110 and the server 120 interact and cooperate to execute, that is, part of the steps of the method are executed by the mobile device 110 and the other steps are executed by the server 120.

[0036] See also Figure 2 , Figure 2 FIG. 1 is a flow chart of a calibration method of a wheel odometer shown in an exemplary embodiment of the present application. The calibration method of the wheel odometer can be applied to Figure 1 It should be understood that the method can also be applied to other exemplary implementation environments and be specifically executed by devices in other implementation environments, and this embodiment does not limit the implementation environment to which the method is applicable.

[0037] like Figure 2 As shown, the calibration method of the wheel odometer includes at least steps S210 to S240, which are described in detail as follows:

[0038] Step S210: Control the mobile device to travel along a preset path, and obtain the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer recorded in the current driving stage; wherein the preset path is composed of straight road sections corresponding to multiple driving stages.

[0039] The mobile device is equipped with a wheel odometer and a scene sensor for collecting scene spatial information. The wheel odometer mainly calculates the distance and direction angle of the steering wheel relative to the ground based on the change in the pulse of the photoelectric encoder within the sampling period; the scene sensor is used to collect scene spatial information, including but not limited to visual sensors, laser sensors, etc.

[0040] The mobile device is controlled to travel along a preset path. The travel speed of the mobile device can be an open-loop speed. Open-loop speed control is a motor control method in which the output of the control system does not depend on any feedback signal from the system.

[0041] The preset route is composed of straight road sections corresponding to a plurality of driving phases, that is, one driving phase corresponds to one straight road section.

[0042] For example, see Figure 3 , Figure 3 A schematic diagram of a preset path is shown in an exemplary embodiment of the present application, such as Figure 3 As shown, the mobile device is controlled to travel back and forth in a straight line between position A and position B, and then one driving stage can be driving from position A to position B or from position B to position A, and the preset path is the path of the mobile device traveling back and forth in a straight line between position A and position B.

[0043] For another example, the preset path may also be a straight path, and one driving phase corresponds to a straight line segment in the straight path.

[0044] The rotation angle of the mobile device sensed by the scene sensor and the rotation angle of the mobile device sensed by the wheel odometer recorded in the current driving stage are obtained when the mobile device is driving along the preset path.

[0045] For a wheel odometer, the change in the recorded direction angle is directly obtained to obtain the rotation angle.

[0046] For the scene sensor, the rotation angle perceived by the scene sensor is obtained by comparing and matching the scene spatial information collected by the scene sensor.

[0047] Taking a scene sensor including a laser sensor as an example, obtaining the rotation angle perceived by the scene sensor recorded in the current driving stage includes: obtaining point cloud data collected by the laser sensor at the start time of driving and the point cloud data collected at the end time of driving in the current driving stage; matching the point cloud data collected at the start time of driving with the point cloud data collected at the end time of driving to obtain the rotation angle perceived by the laser sensor.

[0048] By matching the point cloud data collected at the start of driving with the point cloud data collected at the end of driving, the posture change of the mobile device perceived by the laser sensor is obtained, and then the rotation angle of the mobile device perceived by the scene sensor is obtained.

[0049] Optionally, if the scene sensor includes a visual sensor, the posture change of the mobile device perceived by the visual sensor is obtained by matching the scene image at the start time of driving and the scene image at the end time of driving acquired by the visual sensor, and then the rotation angle of the mobile device perceived by the visual sensor is obtained.

[0050] Optionally, if the scene sensor includes a laser sensor and a visual sensor, a weighted summation may be performed on the rotation angles respectively sensed by the laser sensor and the visual sensor to obtain a final rotation angle sensed by the scene sensor.

[0051] Optionally, the scene sensor can not only calculate the rotation angle of the mobile device based on the scene spatial information (such as point cloud data or image data) collected at the start and end of driving, but also collect scene spatial information once at a preset interval during driving to obtain scene spatial information at multiple moments (including the start and end of driving), match the scene spatial information between adjacent moments to obtain the rotation angle of the mobile device corresponding to the adjacent moments, perform outlier judgment on the rotation angle calculated at each adjacent moment, filter out abnormal rotation angles, and then accumulate the rotation angles after abnormal data filtering to obtain the rotation angle perceived by the scene sensor in the current driving stage.

[0052] Step S220: Taking the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer as a constraint condition, the steering wheel zero bias corresponding to the wheel odometer in the current driving stage is calculated.

[0053] The rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer are taken as constraints to obtain the steering wheel zero bias corresponding to the wheel odometer in the current driving stage.

[0054] For example, see Single Steering Wheel. Figure 4 , Figure 4 FIG. 1 is a schematic diagram of the movement of a single steering wheel shown as an exemplary embodiment of the present application. Figure 4 As shown, the mobile device includes a steering wheel A and two driven wheels B and C. The mobile device defines the angle of the steering wheel A deviating from the front as the steering wheel zero deviation angle θ, and the vertical distance between the steering wheel A and the connecting line of the two driven wheels B and C is the vehicle wheelbase b. Then, the conversion formulas of the moving speed v and angular velocity w of the mobile device and the steering wheel encoding data corresponding to the wheel odometer are as follows:

[0055] v = r·n·cos(θ wheel +θ) Formula 1

[0056] w=r·n·sin(θ wheel +θ) / bFormula 2

[0057] Among them, r is the radius of the steering wheel, n is the steering wheel speed, θ wheel is the steering wheel angle, θ is the steering wheel zero offset for zero offset compensation, and b is the wheelbase (using the structural default value).

[0058] And, according to the hand-eye calibration constraints between the wheel odometer and the scene sensor, we get:

[0059]

[0060] Among them, A is the position increment matrix of the wheel odometer within a period of time, B is the position increment matrix of the scene sensor within the same period of time, X is the external parameter matrix between the wheel odometer and the scene sensor; R A , R X , R B are the rotation matrices corresponding to the wheel odometer, extrinsic matrix, and scene sensor respectively; t A ,t X ,t B They are the wheel odometer, extrinsic matrix, and translation matrix corresponding to the scene sensor.

[0061] According to formula 3, we can get:

[0062] R A ·R X =R X ·R B Formula 4

[0063] R A ·t X +t A =R X ·t B +t X Formula 5

[0064] Among them, Formula 4 is the rotation constraint between the wheel odometer and the scene sensor, and Formula 5 is the translation constraint between the wheel odometer and the scene sensor.

[0065] Based on the above principle, and with the constraint that the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer are equal, we get:

[0066]

[0067] Among them, θ S is the rotation angle perceived by the scene sensor; θ O is the rotation angle sensed by the wheel odometer; i and j are the starting time and the ending time of the current driving phase respectively; w k is time t k Angular velocity of the inner wheel odometer; n k is time t k Steering wheel speed of the inner wheel odometer; θ k is time t k The steering wheel angle of the inboard wheel odometer.

[0068] Then, the steering wheel zero bias corresponding to the wheel odometer in the current driving stage is expressed as the following formula:

[0069]

[0070] Among them, Δθ is the steering wheel zero bias in the current driving stage.

[0071] It should be noted that the steering wheel radius r used in the above formula 7 is the default value of the structure.

[0072] In addition, the above formula for solving the steering wheel zero bias is only an exemplary description, and the specific steps for solving the steering wheel zero bias can be flexibly adjusted according to the actual application scenario, and this application does not limit this.

[0073] Step S230: obtaining the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded during the driving phase when the steering wheel zero bias is less than a preset zero bias threshold, and obtaining the extrinsic rotation matrix between the wheel odometer and the scene sensor.

[0074] Among them, the preset zero bias threshold can be a value pre-set based on experience, such as the preset zero bias threshold is 0.1 degree. The preset zero bias threshold can also be flexibly determined based on the type of mobile device, the type of working scenario of the mobile device, the size parameters of the steering wheel, etc. This application does not make any mutual reference to this.

[0075] The motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded in the driving phase when the steering wheel zero offset is less than a preset zero offset threshold are obtained, wherein the motion offset refers to the position movement of the mobile device.

[0076] In addition, an extrinsic rotation matrix between the wheel odometer and the scene sensor is obtained, where the extrinsic rotation matrix is ​​a rotation matrix in the extrinsic matrix between the wheel odometer and the scene sensor.

[0077] Step S240: The obtained motion offset sensed by the scene sensor, the motion offset sensed by the wheel odometer, and the external parameter rotation matrix are combined to calculate the steering wheel radius corresponding to the wheel odometer.

[0078] Exemplarily, the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the extrinsic parameter rotation matrix are combined to calculate the steering wheel radius corresponding to the wheel odometer, including: taking the product of the motion offset perceived by the scene sensor and the extrinsic parameter rotation matrix and the motion offset perceived by the wheel odometer as the constraint condition, to calculate the steering wheel radius corresponding to the wheel odometer.

[0079] Specifically, based on the translation constraint between the wheel odometer and the scene sensor corresponding to Formula 5, we can obtain:

[0080] t o =(R O-I)·t X +R X ·t S Formula 8

[0081] Among them, t O is the motion offset perceived by the wheel odometer in the current driving stage; t S is the motion offset perceived by the scene sensor in the current driving stage; R O is the rotation matrix perceived by the wheel odometer in the current driving stage; I is the unit matrix; t X is the extrinsic translation matrix between the scene sensor and the wheel odometer, that is, the translation matrix in the extrinsic matrix; R X It is the extrinsic rotation matrix between the scene sensor and the wheel odometer, that is, the rotation matrix in the extrinsic matrix.

[0082] Since the data for calculating the steering wheel radius is obtained only when the steering wheel zero bias is judged to be in a stable convergence state, R O The difference between and I is infinitely close to zero, then Formula 8 can be simplified to:

[0083] t O =R X ·t S Formula 9

[0084] Expanding formula 9 yields:

[0085]

[0086] Among them, θ X is the external parameter angle of the scene sensor in the rotation matrix, and its value is generally 0; t sx is the longitudinal offset perceived by the scene sensor in the current driving stage; t sy It is the lateral offset sensed by the scene sensor in the current driving stage.

[0087] Alternatively, if θ X The value is 0, the mobile device moves in a straight line, and the scene sensor and the mobile device are connected by a rigid body. Therefore, the lateral offset t sy The value of is infinitely close to zero, then the longitudinal offset t in formula 10 sx The solution formula can be simplified to:

[0088]

[0089] The final radius of the steering wheel is:

[0090]

[0091] The steering wheel radius is calculated by solving formula 12 obtained through the above reasoning.

[0092] It should be noted that the above formula for calculating the steering wheel radius is only an example description, and the formula for calculating the steering wheel radius can be flexibly adjusted according to the actual application scenario, and this application does not limit this.

[0093] Next, some embodiments of the present application are described in detail.

[0094] In some embodiments, the method further includes: obtaining the steering wheel zero bias calculated in the previous driving stage; calculating the zero bias compensation value corresponding to the current driving stage based on the steering wheel zero bias calculated in the previous driving stage; and controlling the driving of the mobile device using the zero bias compensation value in the current driving stage.

[0095] Since the current steering wheel zero bias may not have converged yet, the zero bias compensation can be performed for the current driving stage according to the steering wheel zero bias calculated in the previous driving stage.

[0096] Specifically, if the zero bias compensation value used in the previous driving stage is θ (whose initial value can be 0), and the steering wheel zero bias calculated in the previous driving stage is Δθ, then the zero bias compensation value used in the current driving stage is θ=θ+Δθ, and the zero bias compensation value is used to control the driving of the mobile device in the current driving stage.

[0097] By continuously adjusting the zero bias compensation value, the mobile device is controlled to travel in a straight line, so as to gradually reduce the steering wheel zero bias that can be detected in the subsequent driving stage to Δθ.

[0098] In some embodiments, the method also includes: if it is detected that the steering wheel zero bias in the current driving stage is less than a preset zero bias threshold, the number of consecutive cumulative stages is increased by one; if it is detected that the steering wheel zero bias in the current driving stage is not less than the preset zero bias threshold, the number of consecutive cumulative stages is set to zero; in response to the number of consecutive cumulative stages being greater than or equal to the preset number threshold, the current zero bias compensation value is used as the steering wheel zero bias calibration value.

[0099] The preset number threshold can be a value pre-set based on experience, or a value flexibly calculated based on actual conditions. For example, the preset number threshold is flexibly set according to the type of mobile device, the type of working scenario of the mobile device, the size parameters of the steering wheel, etc.; for another example, the difference between the zero bias of the steering wheel in each driving stage is calculated to obtain the zero bias convergence speed of the steering wheel, and the preset number threshold is set based on the zero bias convergence speed of the steering wheel to adapt to different steering wheel installation scenarios and improve the accuracy of the steering wheel zero bias calibration.

[0100] For example, if the preset number threshold is 3, and if the steering wheel zero bias is detected to be less than the preset zero bias threshold of 0.1 degree during three consecutive driving stages, the current zero bias compensation value is used as the steering wheel zero bias calibration value.

[0101] Of course, in addition to determining whether the number of consecutive cumulative stages is greater than or equal to the preset number threshold, the number of driving stages in which the steering wheel zero deviation is less than the preset zero deviation threshold within the preset number of driving stages can also be counted to detect whether the number is greater than or equal to the preset number threshold. This application does not limit this.

[0102] Through the above embodiment, the steering wheel zero bias calibration is achieved.

[0103] The relevant data for calculating the steering wheel radius can be obtained after completing the steering wheel zero bias calibration, or the relevant data for calculating the steering wheel radius can be obtained during the steering wheel zero bias calibration process. This application does not limit this.

[0104] For example, if it is detected that the steering wheel zero deviation in the current driving stage is less than a preset zero deviation threshold, the number of continuous accumulation stages is increased by one; if it is detected that the steering wheel zero deviation in the current driving stage is not less than the preset zero deviation threshold, the number of continuous accumulation stages is reset to zero; in response to the number of continuous accumulation stages being greater than or equal to the preset number threshold, the step of obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero deviation is less than the preset zero deviation threshold is executed.

[0105] Exemplarily, if it is detected that the steering wheel zero deviation in the current driving stage is less than a preset zero deviation threshold, the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the current driving stage are also cached in the candidate data set; if it is detected that the steering wheel zero deviation in the current driving stage is not less than the preset zero deviation threshold, the candidate data set is also cleared; in response to the number of consecutive accumulated stages being greater than or equal to the preset number threshold, the step of obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero deviation is less than the preset zero deviation threshold is executed, including: obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in each driving stage in the candidate data set.

[0106] Through the above embodiment, after determining that the steering wheel zero bias has converged, relevant data that meets the steering wheel radius calculation requirements in the process of correcting the steering wheel zero bias is directly obtained, thereby improving data utilization and improving odometer calibration efficiency.

[0107] It should be noted that the data obtained for solving the steering wheel radius may include the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer in a single driving stage, and may also include the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer in multiple driving stages.

[0108] Exemplarily, the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer of all driving stages associated with the continuous cumulative number of stages in the process of correcting the steering wheel zero bias are used as reference data for solving the steering wheel radius, and the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the external parameter rotation matrix are combined to solve the steering wheel radius corresponding to the wheel odometer, including: combining the motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the external parameter rotation matrix obtained in each driving stage, respectively solving the steering wheel radius corresponding to each driving stage; calculating the average value of the steering wheel radius corresponding to each driving stage, to obtain the steering wheel radius corresponding to the wheel odometer.

[0109] By comprehensively considering the steering wheel radii calculated in multiple driving stages, the average value of the steering wheel radii calculated in each driving stage is used as the final steering wheel radius of the wheel odometer, which can improve the accuracy of the calculated steering wheel radius.

[0110] The calibration method of the wheel odometer provided in the present application controls the mobile device to travel along a preset path, and obtains the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer recorded in the current driving stage; takes the rotation angle perceived by the scene sensor and the rotation angle perceived by the wheel odometer to be equal as a constraint condition, and solves to obtain the steering wheel zero bias corresponding to the wheel odometer in the current driving stage; obtains the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage where the steering wheel zero bias is less than a preset zero bias threshold, and obtains the extrinsic parameter rotation matrix between the wheel odometer and the scene sensor to filter out the perception data recorded after the steering wheel zero bias is stabilized; combines the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the extrinsic parameter rotation matrix to solve to obtain the steering wheel radius corresponding to the wheel odometer, and uses the perception data recorded after the steering wheel zero bias is stabilized to solve to obtain a more accurate steering wheel radius, thereby improving the accuracy of the wheel odometer calibration.

[0111] Figure 5 FIG. 1 is a block diagram of a calibration device for a wheel odometer according to an exemplary embodiment of the present application. Figure 5 As shown, the exemplary wheel odometer calibration device 500 includes: an angle acquisition module 510, a zero bias solution module 520, an offset acquisition module 530 and a steering wheel radius solution module 540. Specifically:

[0112] Angle acquisition module 510, used to control the mobile device to travel along a preset path, and to obtain the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer recorded in the current driving stage; wherein the preset path is composed of straight road segments corresponding to a plurality of driving stages respectively;

[0113] The zero bias solving module 520 is used to solve the steering wheel zero bias corresponding to the wheel odometer in the current driving stage with the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer being equal as a constraint condition;

[0114] The offset acquisition module 530 is used to acquire the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded in the driving stage when the steering wheel zero offset is less than a preset zero offset threshold, and to acquire the external parameter rotation matrix between the wheel odometer and the scene sensor;

[0115] The steering wheel radius calculation module 540 is used to calculate the steering wheel radius corresponding to the wheel odometer by combining the acquired motion offset perceived by the scene sensor, the motion offset perceived by the wheel odometer, and the external parameter rotation matrix.

[0116] It should be noted that the calibration device of the wheel odometer provided in the above embodiment and the calibration method of the wheel odometer provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment, and will not be repeated here. In practical applications, the calibration device of the wheel odometer provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0117] See also Figure 6 , Figure 6 1 is a schematic diagram of the structure of an embodiment of a mobile device of the present application. The mobile device 110 includes a memory 111 and a processor 112, and the processor 112 is used to execute program instructions stored in the memory 111 to implement the steps in any of the above-mentioned wheel odometer calibration method embodiments. In a specific implementation scenario, the mobile device 110 may include but is not limited to: a microcomputer, a server, and in addition, the mobile device 110 may also include a laptop computer, a tablet computer and other mobile devices, which are not limited here.

[0118] Specifically, the processor 112 is used to control itself and the memory 111 to implement the steps in any of the above-mentioned wheel odometer calibration method embodiments. The processor 112 can also be called a central processing unit (CPU). The processor 112 may be an integrated circuit chip with signal processing capabilities. The processor 112 can also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. In addition, the processor 112 can be implemented by an integrated circuit chip.

[0119] See also Figure 7 , Figure 7 The computer-readable storage medium 700 stores program instructions 710 that can be executed by a processor, and the program instructions 710 are used to implement the steps in any of the above-mentioned wheel odometer calibration method embodiments.

[0120] In some embodiments, the functions or modules included in the device provided by the embodiments of the present disclosure can be used to execute the method described in the above method embodiments. The specific implementation can refer to the description of the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0121] The above description of various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other, and for the sake of brevity, they will not be repeated herein.

[0122] In the several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device implementation described above is only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation, such as units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0123] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit. If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (processor) to perform all or part of the steps of each implementation method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), disk or optical disk and other media that can store program code.

Claims

1. A calibration method for a wheel odometer, characterized in that: A wheel odometer and a scene sensor for collecting scene spatial information are deployed in the mobile device, and the method includes: Controlling the mobile device to travel along a preset path, and obtaining the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer recorded in the current driving stage; wherein the preset path is composed of straight road sections corresponding to a plurality of driving stages respectively; Taking the rotation angle sensed by the scene sensor and the rotation angle sensed by the wheel odometer as a constraint condition, solving and obtaining the steering wheel zero bias corresponding to the wheel odometer in the current driving stage; Obtaining the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded during the driving phase in which the steering wheel zero bias is less than a preset zero bias threshold, and obtaining an external parameter rotation matrix between the wheel odometer and the scene sensor; The obtained motion offset sensed by the scene sensor, the motion offset sensed by the wheel odometer, and the external parameter rotation matrix are combined to calculate the steering wheel radius corresponding to the wheel odometer.

2. The method according to claim 1, characterized in that Before obtaining the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded during the driving phase in which the steering wheel zero bias is less than a preset zero bias threshold, the method further includes: If it is detected that the steering wheel zero deviation in the current driving stage is less than the preset zero deviation threshold, the number of consecutive accumulation stages is increased by one; If it is detected that the steering wheel zero bias in the current driving stage is not less than the preset zero bias threshold, the number of consecutive accumulated stages is set to zero; In response to the number of consecutive accumulated stages being greater than or equal to a preset number threshold, the step of obtaining the motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in the driving stage in which the steering wheel zero bias is less than the preset zero bias threshold is performed.

3. The method according to claim 2, characterized in that If it is detected that the steering wheel zero offset in the current driving stage is less than a preset zero offset threshold, the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded in the current driving stage are also cached in the candidate data set; If it is detected that the steering wheel zero bias in the current driving stage is not less than the preset zero bias threshold, the candidate data set is also cleared; In response to the number of consecutive accumulation stages being greater than or equal to a preset number threshold, the step of obtaining the motion offset sensed by the scene sensor and the motion offset sensed by the wheel odometer recorded in the driving stage in which the steering wheel zero bias is less than a preset zero bias threshold comprises: The motion offset perceived by the scene sensor and the motion offset perceived by the wheel odometer recorded in each driving stage in the candidate data set are obtained.

4. The method according to claim 3, characterized in that The combining the acquired motion offset sensed by the scene sensor, the motion offset sensed by the wheel odometer, and the external parameter rotation matrix to calculate the steering wheel radius corresponding to the wheel odometer includes: The steering wheel radius corresponding to each driving stage is calculated by combining the motion offset sensed by the scene sensor, the motion offset sensed by the wheel odometer, and the external parameter rotation matrix obtained in each driving stage; The average value of the steering wheel radius corresponding to each driving stage is calculated to obtain the steering wheel radius corresponding to the wheel odometer.

5. The method according to claim 1, characterized in that The combining the acquired motion offset sensed by the scene sensor, the motion offset sensed by the wheel odometer, and the external parameter rotation matrix to calculate the steering wheel radius corresponding to the wheel odometer includes: The steering wheel radius corresponding to the wheel odometer is obtained by solving the constraint condition that the product of the motion offset sensed by the scene sensor and the extrinsic rotation matrix is ​​equal to the motion offset sensed by the wheel odometer.

6. The method according to claim 1, characterized in that The method further comprises: Obtain the steering wheel zero bias calculated in the previous driving stage; Based on the steering wheel zero bias calculated in the previous driving stage, a zero bias compensation value corresponding to the current driving stage is calculated; The mobile device is controlled to travel using the zero bias compensation value during the current travel phase.

7. The method according to claim 6, characterized in that The method further comprises: If it is detected that the steering wheel zero deviation in the current driving stage is less than the preset zero deviation threshold, the number of consecutive accumulation stages is increased by one; If it is detected that the steering wheel zero bias in the current driving stage is not less than the preset zero bias threshold, the number of consecutive accumulated stages is set to zero; In response to the number of consecutive accumulation stages being greater than or equal to a preset number threshold, the current zero bias compensation value is used as the steering wheel zero bias calibration value.

8. The method according to claim 1, characterized in that The scene sensor includes a laser sensor; obtaining the rotation angle sensed by the scene sensor recorded in the current driving stage includes: Acquire point cloud data collected by the laser sensor at the start time of driving and point cloud data collected at the end time of driving in the current driving stage; The point cloud data collected at the start time of the driving and the point cloud data collected at the end time of the driving are matched to obtain the rotation angle sensed by the laser sensor.

9. A mobile device, characterized in that: The mobile device comprises a memory and a processor, wherein the processor is configured to execute program instructions stored in the memory to implement the steps in the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program instructions, and the program instructions can be executed by a processor to implement the steps in the method according to any one of claims 1 to 8.

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