Acceleration sensor signal correction method and computer storage medium

Abstract

The invention discloses an acceleration sensor signal correction method which comprises the following steps: acquiring continuous altitude information of a road within a preset distance in front of a vehicle, judging whether a continuous straight road section exists or not based on the continuous altitude information, and activating an acceleration calibration mode if the continuous straight road section exists; a vehicle driving system is controlled, so that the vehicle is sequentially stabilized at at least two different target vehicle speed points on the straight road section; at each stable target vehicle speed point, acceleration measurement values output by the IMU are collected, and an average value is taken as a deviation value of the acceleration; and substituting the deviation value into an IMU sensor correction table, and carrying out acceleration sensor signal correction. Zero extra hardware cost correction is realized by using natural characteristics of a driving road, the limitation of a traditional static calibration method is overcome, and the problem of signal distortion caused by zero drift of an acceleration sensor in a dynamic driving environment is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automotive electronic control technology, and particularly relates to a method for correcting IMU (inertial measurement unit) acceleration sensor signals in real time based on road elevation information. BACKGROUND

[0002] Traditional acceleration sensor correction needs to be manually calibrated on a water platform, which has problems such as low efficiency, complex environment construction, and insufficient dynamic accuracy due to static condition limitations. Existing technologies cannot realize real-time error compensation during vehicle driving. SUMMARY

[0003] In view of the technical defects and technical disadvantages in the prior art, the embodiments of the present application provide an acceleration sensor signal correction method and a computer storage medium to overcome the above problems or at least partially solve the above problems, and the specific solutions are as follows:

[0004] As a first aspect of the present application, an acceleration sensor signal correction method is provided, comprising:

[0005] Obtaining continuous elevation information of a road within a predetermined distance in front of the vehicle, determining whether there is a continuous straight road section based on the continuous elevation information, and activating an acceleration calibration mode if there is; controlling the vehicle driving system to make the vehicle stabilize at at least two different target speed points on the straight road section in turn; collecting acceleration measurement values output by the IMU at each stable target speed point;

[0006] Calculating the average value of all collected acceleration measurement values as the bias value of acceleration, substituting the bias value into the IMU sensor correction table, and correcting the acceleration sensor signal.

[0007] Further, the continuous elevation information is obtained in the following manner:

[0008] Obtaining road elevation data within a predetermined distance in front of the vehicle through a vehicle-mounted GPS map system; discretely sampling the road in front at fixed intervals to obtain a series of discrete elevation values; storing the discrete elevation values in order as an ordered array A, where each element of the array A corresponds to the elevation value of a sampling point, and the actual distance between adjacent sampling points is equal.

[0009] Further, the ordered array is transmitted to a control unit through a vehicle bus system, and a slope calculation process is performed in the control unit, which includes: calculating slope parameters based on adjacent elevation values in the ordered array; each slope parameter represents the slope characteristics of the road section between adjacent sampling points; generating a slope array corresponding to the elevation array, where each element of the slope array reflects the elevation change rate of a specific road section.

[0010] Further, the determination of the continuous straight section needs to satisfy the following conditions simultaneously: (a) slope stability: there are continuous multiple sampling points in the slope array, and the absolute values of all slope values of the multiple sampling points do not exceed a first slope threshold value (in theory, the absolute value of the slope value should be close to 0 to represent a straight section, therefore, the first slope threshold value should be as close to 0 as possible); (b) continuous length: the number of the continuous multiple sampling points is determined according to the product of the current vehicle speed and a fixed time threshold value, divided by the sampling point interval.

[0011] Further, in the acceleration calibration process:

[0012] The slope value corresponding to the current vehicle position is monitored in real time;

[0013] When the absolute value of the current slope exceeds the slope threshold value or the slope change rate exceeds the change rate threshold value, the calibration is immediately terminated and the collected data is cleared;

[0014] A differentiated recovery strategy is executed according to the calibration termination timing, and a minimum retry interval is triggered.

[0015] Further, the target vehicle speed points include a basic vehicle speed and at least one incremental vehicle speed, the incremental vehicle speed being a fixed speed increment, at each target vehicle speed point, the absolute value of the actual acceleration of the vehicle does not exceed an acceleration threshold value, and lasts for a predetermined stable time, the actual acceleration is calculated by dividing the driving torque of the vehicle by the mass of the vehicle, minus the combined force of the rolling resistance and the air resistance, the coefficients of the rolling resistance and the air resistance are calibrated through a standard coasting resistance test.

[0016] Further, the standard coasting resistance test is realized by the following steps:

[0017] Coasting at idle on a horizontal test road, starting from a set starting vehicle speed to collect vehicle speed decay data;

[0018] Establish a differential equation of the relationship between the vehicle speed decay rate and the vehicle speed; after discretizing the continuous equation, the least squares method is used to fit and solve the optimal solution of the resistance coefficient;

[0019] When the goodness of fit exceeds a predetermined value, it is determined that the calibration is valid.

[0020] Further, the vehicle driving system is a permanent magnet synchronous motor, and the torque balance control is realized by:

[0021] Calculating the required torque based on the driving resistance;

[0022] Setting the q-axis current command to the quotient of the required torque and the motor torque constant through the field-oriented control algorithm;

[0023] When the deviation between the actual output torque of the motor and the required torque does not exceed the torque threshold, and the absolute value of the vehicle acceleration does not exceed the acceleration threshold for a predetermined time, the equilibrium point is determined to be reached.

[0024] Furthermore, after completing the calibration, closed-loop verification is performed, including:

[0025] Acceleration data were recollected under the same road conditions and vehicle speeds.

[0026] Calculate the mean and standard deviation of the collected data;

[0027] The correction is considered valid when the mean and standard deviation do not exceed the corresponding predetermined bias tolerance and predetermined noise tolerance, respectively.

[0028] If the calibration is ineffective, the previous parameters will be restored, a diagnostic fault code will be triggered, and subsequent automatic calibration will be disabled.

[0029] As a second aspect of the present invention, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a computer, the computer program causes the computer to perform the acceleration sensor signal correction method as described in any of the preceding claims.

[0030] The present invention has the following beneficial effects:

[0031] 1. Dynamic real-time performance: It achieves zero additional hardware cost correction by utilizing the natural features of the driving road, overcoming the limitations of traditional static calibration methods.

[0032] 2. Improved accuracy: Multi-speed point calibration reduces acceleration deviation compensation error to within ±0.02g.

[0033] 3. Enhanced safety: The slope change monitoring mechanism avoids control failures caused by miscalibration. Attached Figure Description

[0034] Figure 1 This is a flowchart illustrating an acceleration sensor signal correction method provided in an embodiment of the present invention. Detailed Implementation

[0035] 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 a part of the present invention, and not all of the 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.

[0036] For a better understanding of the technical solutions of the present application, the exemplary embodiments of the present application are described below in conjunction with the drawings, which include various details of the embodiments of the present application to help understanding, and should be considered as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, for the sake of clarity and conciseness, the description below omits the description of well-known functions and structures.

[0037] In the case of no conflict, each embodiment of the present application and each feature in the embodiments can be combined with each other.

[0038] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0039] The terms used herein are only used to describe specific embodiments, and are not intended to limit the present application. As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms "comprise" and / or "consist of", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The terms "connected" or "coupled" and / or similar terms are not limited to a physical or mechanical connection, but can include an electrical connection, whether direct or indirect.

[0040] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present application, and will not be interpreted in an overly formal or overly literal sense unless expressly so defined herein.

[0041] In the technical solutions of the present application, the collection, storage, use, processing, transmission, provision and disclosure of user personal information comply with relevant laws and regulations, and do not violate public order and good customs. The use of user data in the technical solutions complies with relevant national laws and regulations (for example, "Information Security Technology Personal Information Security Specification" and the like). For example, appropriate measures are taken for personal information access control; restrictions are given for the display of personal information; the use purpose of personal information does not exceed the direct or reasonably related range; the use of personal information eliminates the explicit identity pointing and avoids precise positioning to a specific individual.

[0042] To solve at least one of the problems in the related art, the application provides an acceleration sensor signal correction method. Figure 1 A flowchart of an acceleration sensor signal correction method provided by the embodiment of the application is shown in the figure, and the method comprises the following steps:

[0043] Continuous elevation information of a road within a predetermined distance in front of a vehicle is acquired, and it is determined whether there is a continuous straight road section based on the continuous elevation information, and if there is, an acceleration calibration mode is activated; a vehicle driving system is controlled to make the vehicle stably stay at at least two different target speed points on the straight road section; and acceleration measurement values output by an IMU are collected at each stable target speed point.

[0044] An average value of all the collected acceleration measurement values is calculated as a bias value of acceleration, the bias value is substituted into an IMU sensor correction table, and acceleration sensor signal correction is performed.

[0045] The application acquires continuous elevation information of a road in front by a GPS map, discretizes the road into an ordered array (with a fixed sampling point interval), calculates a slope array to determine a straight road section (with a slope close to zero), controls the vehicle to stably stay at at least two target speed points on the straight road section, collects IMU acceleration measurement values to take an average as a bias value, and writes the bias value into an IMU correction table to realize dynamic signal correction.

[0046] The application uses natural road characteristics to replace a water platform calibration, breaks through the environmental limitation (a special device is needed) of traditional static calibration, and realizes zero hardware cost. Zero point drift can be compensated in real time during driving, and the signal distortion problem caused by temperature change and vibration in the traditional method is solved (the existing technology only supports pre-delivery calibration).

[0047] In some embodiments, the continuous elevation information is acquired in the following manner:

[0048] Road elevation data within a predetermined distance in front of a vehicle is acquired by a vehicle-mounted GPS map system; the road in front is discretized and sampled at a fixed interval to obtain a series of discrete elevation values; and the discrete elevation values are stored as an ordered array A in the order of sampling points, wherein each element of the array A corresponds to an elevation value of a sampling point, and the actual distance between adjacent sampling points is equal.

[0049] In some embodiments, the ordered array is transmitted to a control unit through a vehicle bus system, and a slope calculation process is performed in the control unit, which comprises the following steps: slope parameters are calculated based on adjacent elevation values in the ordered array; each slope parameter represents the slope characteristics of a road section between adjacent sampling points; a slope array corresponding to the elevation array is generated, wherein each element of the slope array reflects the elevation change rate of a specific road section.

[0050] Taking the discrete sampling at 20m intervals of 2km road as an example, the continuous elevation information is obtained in the following way:

[0051] The elevation data of the road ahead is received by the vehicle-mounted GPS map system, wherein:

[0052] The data collection range covers the road 2km ahead of the vehicle;

[0053] The elevation data is discretely sampled at a preset road sampling interval;

[0054] The discrete sampling results are stored as an ordered array A, satisfying the relationship A=[H1, H2,..., HM]

[0055] Where Hk represents the elevation value at 20×(k-1) meters from the current position of the vehicle (k=1, 2,..., M), and M is the total number of sampling points.

[0056] The slope calculation process is performed in the control unit ECU, which includes: generating a slope array R based on array A, where each element R[k] of the slope array is calculated by the following difference formula: R[k]=(A[k+1]-A[k]) / ΔL, (k=1, 2,..., M-1); where:

[0057] k is the index number of the slope array element;

[0058] ΔL is the preset road sampling interval;

[0059] M is the total number of elements in array A;

[0060] R[k] represents the slope value of the road segment from ΔL×(k-1) meters to ΔL×k meters from the current position of the vehicle.

[0061] In the above embodiment, the discrete processing avoids the jump interference of GPS original data (the existing technology directly uses GPS slope data which is easily affected by signal fluctuations), and the ordered array structure optimizes the real-time calculation performance, meeting the real-time requirements of the vehicle control system.

[0062] In some embodiments, the determination of the continuous straight road segment must satisfy the following conditions: (a) Slope stability: there are a plurality of continuous sampling points in the slope array, and the absolute values of all slope values of the plurality of sampling points do not exceed a first slope threshold value (the threshold value tends to zero); (b) Continuous length: the number of continuous sampling points is determined according to the product of the current vehicle speed and a fixed time threshold value divided by the sampling point interval.

[0063] In the above embodiment, since the first slope threshold value is as close to 0 as possible, in theory, the absolute value of the slope value should be close to 0 to represent a straight road section, that is, the absolute values of the slope values of a plurality of consecutive sampling points in the slope array are close to 0. Taking the case where the slope value is equal to 0 as an example, when it is identified that the front slope is R[N]=0, counting is started, and the number of counts X=the current vehicle speed*1min / 60*1000 / 20 is determined. If R is 0 from N to X, the acceleration updating correction calculation is started, otherwise the current acceleration value is maintained.

[0064] In the above embodiment, the minimum length requirement of the straight road section is adjusted according to the vehicle speed (the existing technology uses a fixed distance, which is easy to cause calibration failure due to changes in vehicle speed), and the slope stability and length are verified to avoid interference of short-time pseudo-straight road sections (such as bridge joints).

[0065] In some embodiments, during the acceleration calibration process:

[0066] The slope value corresponding to the current vehicle position is monitored in real time;

[0067] When the absolute value of the current slope exceeds the slope threshold value or the slope change rate exceeds the change rate threshold value, the calibration is immediately terminated and the collected data is cleared;

[0068] A differentiated recovery strategy is executed according to the calibration termination timing, and a minimum retry interval timing is triggered.

[0069] In the above embodiment, the absolute value of the slope and the change rate are monitored in real time, and when the threshold value is exceeded, the calibration is immediately terminated and the data is cleared, the minimum retry interval timing is triggered, the frequent invalid attempts are prevented, the error calibration caused by sudden slope is avoided (the traditional method has no real-time interruption mechanism and may output dangerous compensation values), and the system redundant calculation is reduced through the differentiated recovery strategy.

[0070] In some embodiments, the target vehicle speed points include a basic vehicle speed and at least one incremental vehicle speed, the incremental vehicle speed is a fixed speed increment, at each target vehicle speed point, the absolute value of the actual acceleration of the vehicle does not exceed the acceleration threshold value, and the actual acceleration is maintained for a predetermined stable time, the actual acceleration is calculated by dividing the resultant force of the driving torque of the vehicle minus the rolling resistance and air resistance by the mass of the vehicle, and the coefficients of the rolling resistance and air resistance are calibrated through standard sliding resistance test.

[0071] For example, a basic target vehicle speed Vb and an incremental vehicle speed ΔV are defined to generate a target vehicle speed sequence: {Vt}={Vb,Vb+ΔV,Vb+2ΔV, }, assuming that ΔV=5.0±0.5 km / h and the number of sequence elements n≥2. At each target vehicle speed point Vt, the following conditions are met: maxt ∈[t0,t0+T]∣a actual (t)∣≤ε a Optionally, ε a =0.01 m / s2, T=3 seconds; a actual is calculated in real time by the vehicle dynamics model:

[0072]

[0073] wherein a actual (t) is the actual acceleration time-domain function, t is the time variable, t0 is the starting time of the steady state, T is the duration of the steady state, ε a is the upper limit of the acceleration allowable error, which is the threshold value for determining whether the vehicle is in a "zero acceleration equilibrium state", max t is the maximum function, which extracts the peak value of the absolute value of the acceleration in the time interval [t_0, t_0+T] to ensure that the steady state condition is met throughout the journey, m is the mass of the vehicle, F w is the rolling resistance, F w is the air resistance, and F j is the total driving force of the driving wheels (unit: N), which is converted from the driving torque T j : F j =T j / r w , r w is the wheel radius, the rolling resistance static friction component coefficient A (unit: m / s²), the rolling resistance speed-related component coefficient B (unit: ), and the air resistance coefficient C (unit: kg / m) are obtained by standard coasting resistance test calibration.

[0074] The standard coasting resistance test calibration is achieved by the following steps:

[0075] Coasting with the transmission in neutral on a horizontal test road, starting at a speed higher than the set starting speed to collect speed decay data;

[0076] Establish a differential equation of the speed decay rate and speed relationship. After discretizing the continuous equation, the least squares method is used to fit and solve the optimal solution of the resistance coefficient;

[0077] When the goodness of fit exceeds the predetermined value, the calibration is determined to be valid.

[0078] In the above embodiments, the resistance coefficient is fitted by actual measurement to eliminate the error of the theoretical model (existing technology uses fixed parameter table and ignores changes such as tire wear), and the goodness of fit threshold is used to ensure the validity of the calibration (to avoid invalid data polluting the system).

[0079] In some embodiments, the vehicle drive system is a permanent magnet synchronous motor, and the torque balance control is performed by:

[0080] calculating a demand torque based on the driving resistance;

[0081] setting a q-axis current command by a magnetic field oriented control algorithm as a quotient of the demand torque and a motor torque constant;

[0082] determining that a balance point is reached when a deviation between an actual output torque of the motor and the demand torque does not exceed a torque threshold, and an absolute value of a vehicle acceleration does not exceed an acceleration threshold for a predetermined time.

[0083] In some embodiments, performing closed-loop verification after the correction is completed includes:

[0084] recording acceleration data under the same road section and vehicle speed condition;

[0085] calculating a mean value and a standard deviation of the recorded data;

[0086] determining that the correction is valid when the mean value and the standard deviation do not exceed a predetermined bias tolerance and a predetermined noise tolerance, respectively;

[0087] if the correction is not valid, restoring previous parameters, triggering a diagnostic fault code, and disabling subsequent automatic calibration.

[0088] In the above embodiments, data is recorded under the same road section / vehicle speed condition, a mean value (bias tolerance) and a standard deviation (noise tolerance) are calculated, and if the values exceed the thresholds, old parameters are restored, a fault code is triggered, and automatic calibration is disabled, so that invalid correction is automatically rolled back, system safety is ensured (existing technologies lack closed-loop verification), and sensor aging or abnormal interference is identified through standard deviation monitoring.

[0089] The embodiments of the present application also provide a computer readable storage medium, characterized in that the computer readable storage medium stores a computer program, and the computer program is executed by a computer to make the computer execute the acceleration sensor signal correction method according to any one of the above embodiments.

[0090] Those of ordinary skill in the art will realize and understand that all or some of the steps in the methods disclosed above and the functional modules / units in the systems and devices can be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementation, the division between the functional modules / units referred to in the above description does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be performed by several physical components in cooperation. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on computer readable storage media, which can include computer storage media (or non-transitory media) and communication media (or transitory media).

[0091] As is well known to those of ordinary skill in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable program instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM), static random access memory (SRAM), flash memory or other memory technology, portable compact disc read only memory (CD-ROM), digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by a computer. Further, it is well known to those of ordinary skill in the art that communication media typically embodies computer readable program instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. As a result, the foregoing description of computer storage media, along with communication media, applies to and fully integrates software and / or programs such as program modules, program data, and / or computer readable program instructions.

[0092] Computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing / processing device.

[0093] Computer readable program instructions for carrying out operations of the present application can be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate array (FPGA), or programmable logic array (PLA) can execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present application.

[0094] The computer program product described herein can be embodied in a specific manner by hardware, software, or a combination thereof. In an optional embodiment, the computer program product is embodied as a computer storage medium. In another optional embodiment, the computer program product is embodied as a software product, such as a software development kit (SDK), and the like.

[0095] The computer program product described herein can be embodied in a specific manner by hardware, software, or a combination thereof. In an optional embodiment, the computer program product is embodied as a computer storage medium. In another optional embodiment, the computer program product is embodied as a software product, such as a software development kit (SDK), and the like.

[0096] These computer readable program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer readable program instructions can also be stored in a computer readable storage medium that can include a non-transitory computer readable storage medium that can be a computer- readable storage medium having no data storage cycles that change state. The instructions can be executed by one or more processors of a computer, to cause a series of operational steps to be performed on the computer to produce a computer-implemented process. The instructions can also cause one or more processors of a computer or other programmable data processing apparatus to

[0097] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable data processing apparatus, or other device implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0098] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable data processing apparatus, or other device implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0099] Example embodiments have been disclosed herein and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that features, characteristics or aspects described in relation to one embodiment can be applied to other embodiments, unless otherwise clearly claimed. Accordingly, it will be understood by those skilled in the art that various changes in form and details can be made without departing from the scope of the present application as set forth in the appended claims.

[0100] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An acceleration sensor signal correction method characterized by, The method comprises the following steps: Obtaining continuous elevation information of a road within a predetermined distance in front of the vehicle, determining whether there is a continuous flat road section based on the continuous elevation information, and activating an acceleration calibration mode if there is a continuous flat road section; Controlling the vehicle driving system to make the vehicle stabilize at at least two different target speed points on the flat road section in turn; 2. The acceleration sensor signal correction method according to claim 1, characterized by, Collecting acceleration measurement values output by the IMU at each stable target speed point; Calculating the average value of all collected acceleration measurement values as the bias value of acceleration, and substituting the bias value into the IMU sensor correction table to correct the acceleration sensor signal.

3. The acceleration sensor signal correction method according to claim 1, characterized by, The continuous elevation information is obtained in the following way:

4. The acceleration sensor signal correction method according to claim 3, characterized by, Obtaining road elevation data within a predetermined distance in front of the vehicle through a vehicle-mounted GPS map system; Discretely sampling the front road at fixed intervals to obtain a series of discrete elevation values; 5. The acceleration sensor signal correction method according to claim 4, characterized by, Storing the discrete elevation values in order as an ordered array A, where each element of the array A corresponds to the elevation value of a sampling point, and the actual distance between adjacent sampling points is equal. The ordered array is transmitted to the control unit through the vehicle bus system, and the slope calculation process is performed in the control unit, which includes: Calculating the slope parameter based on the adjacent elevation values in the ordered array; Each slope parameter represents the slope characteristics of the road section between adjacent sampling points; 6. The acceleration sensor signal correction method according to claim 1, characterized by, Generating a slope array corresponding to the elevation array, where each element of the slope array reflects the elevation change rate of a specific road section.

7. The acceleration sensor signal correction method according to claim 6, characterized by, The determination of the continuous flat road section needs to meet the following conditions at the same time: (a) Slope stability: the absolute values of the slope values of a plurality of continuous sampling points in the slope array are all less than a first slope threshold value; (b) Continuous length: the number of the plurality of continuous sampling points is determined according to the product of the current vehicle speed and a fixed time threshold value, divided by the sampling point interval. In the acceleration calibration process: Real-time monitoring of the slope value corresponding to the current vehicle position; 8. The acceleration sensor signal correction method according to claim 1, characterized by, When the absolute value of the current slope exceeds the slope threshold value or the slope change rate exceeds the change rate threshold value, the calibration is immediately terminated and the collected data is cleared; According to the calibration termination time, a differentiated recovery strategy is executed, and a minimum retry interval is triggered. The target speed points include a basic speed and at least one incremental speed, the incremental speed being a fixed speed increment, at each target speed point, the absolute value of the actual acceleration of the vehicle is required to be less than an acceleration threshold value, and the actual acceleration is calculated by dividing the rolling resistance and air resistance by the vehicle mass, the coefficients of the rolling resistance and air resistance are calibrated through a standard coasting resistance test. The standard coasting resistance test is realized by the following steps: Coasting on a horizontal test road from a speed higher than a set starting speed to collect speed decay data; Establishing a differential equation of the relationship between the speed decay rate and the speed; Discretizing the continuous equation and solving the optimal solution of the resistance coefficient by least squares method; When the goodness of fit exceeds a predetermined value, the calibration is determined to be valid. The vehicle driving system is a permanent magnet synchronous motor, and the torque balance control is realized by: Calculating the required torque based on the driving resistance; The q-axis current command is set to the quotient of the demanded torque and a motor torque constant by a field-oriented control algorithm; When the deviation between the actual output torque of the motor and the demanded torque does not exceed a torque threshold, and the absolute value of the vehicle acceleration does not exceed an acceleration threshold for a predetermined time, it is determined that the balance point is reached.

9. The acceleration sensor signal correction method according to claim 1, characterized by, The closed-loop verification after correction includes: Re-acquiring acceleration data under the same road section and vehicle speed conditions; Calculating the average and standard deviation of the acquired data; When the average and standard deviation do not exceed the corresponding predetermined bias tolerance and predetermined noise tolerance, respectively, it is determined that the correction is valid; If the correction is invalid, the previous parameters are restored, a diagnostic fault code is triggered, and subsequent automatic calibration is disabled.

10. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by a computer to make the computer execute the acceleration sensor signal correction method according to any one of claims 1 to 9.

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