Vehicle acceleration and gradient signal separation method, electronic equipment and vehicle

Abstract

The invention discloses a vehicle acceleration and gradient signal separation method, electronic equipment and a vehicle. The method comprises the steps of calculating vehicle speed according to actual working conditions and wheel speed signals of a vehicle; based on the vehicle speed, a five-point difference method is adopted to calculate the wheel acceleration; and according to the motion state of the vehicle and the wheel acceleration, carrying out signal separation on an acceleration signal detected by an acceleration sensor to obtain the actual acceleration and gradient of the vehicle. According to the method, the signal coupling error is remarkably reduced through working condition wheel speed processing and Kalman filtering. A five-point difference method is adopted to improve the acceleration calculation precision and adapt to dynamic working condition changes. Meanwhile, the low-pass filtering and delay compensation design is added, noise is effectively restrained, and the real-time performance is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicles, and in particular relates to a method for separating vehicle acceleration and slope signals, an electronic device, and a vehicle. Background Art

[0002] In existing vehicle dynamics control, there's a coupling problem between acceleration and slope signals. Traditional methods rely primarily on a single sensor or simple filtering algorithms to separate the signals, but these methods suffer from the following issues: 1) Signal coupling error: The vertical components of both vehicle acceleration and slope affect the acceleration sensor output, preventing direct separation. 2) Poor adaptability to dynamic operating conditions: Wheel speed signal noise and delay characteristics vary under different operating conditions (acceleration, braking, and constant speed). Traditional methods fail to address these conditions separately, resulting in reduced accuracy. 3) Sensor noise and delay: Wheel speed signals introduce noise due to tire slip and road surface unevenness, and acceleration sensor response delays, impacting real-time performance. Summary of the Invention

[0003] An object of the present invention is to provide a method for separating vehicle acceleration and slope signals, an electronic device, and a vehicle, which can solve the above-mentioned technical problems in the prior art.

[0004] According to a first aspect of the present invention, a method for separating vehicle acceleration and slope signals is provided, comprising:

[0005] Calculate vehicle speed based on actual vehicle operating conditions and wheel speed signals;

[0006] Calculating wheel acceleration based on the vehicle speed using a five-point difference method;

[0007] According to the motion state of the vehicle and the wheel acceleration, the acceleration signal detected by the acceleration sensor is separated to obtain the actual acceleration and slope of the vehicle.

[0008] Optionally, the calculating the wheel acceleration based on the vehicle speed using a five-point difference method includes:

[0009] Calculate the wheel acceleration using the following formula:

[0010] ;

[0011] in, is the wheel acceleration, is the time step, Indicates the current moment, is the vehicle speed, for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the vehicle at the moment.

[0012] Optionally, the performing signal separation on the acceleration signal detected by the acceleration sensor according to the motion state of the vehicle and the wheel acceleration to obtain the actual acceleration and slope of the vehicle includes:

[0013] When the vehicle is moving, constructing a state equation and an observation equation of the vehicle according to the wheel acceleration;

[0014] Based on the state equation of the vehicle and the observation equation, performing signal separation on the acceleration signal detected by the acceleration sensor through Kalman filtering to obtain the actual acceleration and slope of the vehicle;

[0015] When the vehicle is stationary, the actual acceleration of the vehicle is determined to be zero, and the slope is calculated based on the acceleration signal detected by the acceleration sensor.

[0016] Optionally, the state equation of the vehicle is:

[0017] ;

[0018] in, is the actual acceleration of the vehicle, is the wheel acceleration, is the acceleration due to gravity, is the slope angle, for The slope angle at the moment, for The slope angle at the moment, and is the process noise.

[0019] Optionally, the observation equation is:

[0020] ;

[0021] in, is the observation vector, is the acceleration detected by the acceleration sensor, is the wheel acceleration, is the actual acceleration of the vehicle, is the acceleration due to gravity, is the slope angle, is the observation noise.

[0022] Optionally, the method further includes:

[0023] Introducing a first-order delay model into the observation equation to correct the acceleration sensor signal delay;

[0024] ;

[0025] in, is the observation vector, is the delayed observation vector, is the delay time, is a complex frequency domain variable.

[0026] Optionally, calculating the vehicle speed according to the actual operating condition of the vehicle and the wheel speed signal includes:

[0027] Under acceleration conditions, the average of the non-driving wheel speeds is taken as the vehicle speed;

[0028] Under braking conditions, the maximum value of the average of the front wheel speed and the average of the rear wheel speed is taken as the vehicle speed;

[0029] Under other working conditions, the average of the wheel speeds of all wheels is taken as the vehicle speed.

[0030] Optionally, the method further includes: performing low-pass filtering on the vehicle speed signal using a second-order Butterworth filter, where the second-order Butterworth filter is expressed as follows:

[0031] ;

[0032] in, is the transfer function of the filter, is the cutoff frequency, is a complex frequency domain variable.

[0033] According to a second aspect of the present invention, an electronic device is provided, comprising a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the steps of a method for separating vehicle acceleration and slope signals as described in the first aspect of the present invention are implemented.

[0034] According to a third aspect of the present invention, a vehicle is provided, comprising the electronic device according to the second aspect of the present invention.

[0035] The present invention significantly reduces signal coupling errors through wheel speed processing based on operating conditions and Kalman filtering. It also employs a five-point differential method to improve acceleration calculation accuracy and adapt to dynamic operating conditions. Furthermore, low-pass filtering and delay compensation are incorporated to effectively suppress noise and improve real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The figure is a flow chart of a method for separating vehicle acceleration and slope signals in an embodiment of the present invention.

[0037] Figure 2Schematic diagram of a method for separating vehicle acceleration and slope signals in an embodiment of the present invention.

[0038] Figure 3 4 is a flow chart of vehicle speed calculation in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention.

[0040] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0041] Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0042] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0043] In the present description, references to features referred to as "first" or "second" may explicitly or implicitly include one or more of these features. In the present description, unless otherwise specified, "plurality" means two or more. Furthermore, the term "and / or" in this specification refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0044] like Figure 1 As shown, this embodiment introduces a method for separating vehicle acceleration and slope signals, including steps 1100-1300.

[0045] Step 1100: Calculate the vehicle speed based on the actual vehicle operating conditions and wheel speed signals.

[0046] There are many operating conditions when a vehicle is actually running, such as acceleration condition, braking condition, etc. In the present invention, different methods are used to calculate the vehicle speed under different operating conditions to improve the accuracy of the calculation results.

[0047] The wheel speed signal is collected by the vehicle's wheel speed sensor. The vehicle in the present invention is a four-wheel passenger car, each wheel is equipped with a corresponding wheel speed sensor, and the wheel speed sensor signal includes the wheel speed signals of the four wheels, such as Figure 2 As shown, they are the wheel speed signal V_lf of the left front wheel, the wheel speed signal V_rf of the right front wheel, the wheel speed signal V_lr of the left rear wheel, and the wheel speed signal V_rr of the right rear wheel.

[0048] Step 1200: Calculate the wheel acceleration based on the vehicle speed using a five-point difference method.

[0049] The five-point differential method uses vehicle speeds at multiple different times to calculate acceleration through symmetrical differences. This significantly reduces noise interference and improves accuracy.

[0050] Specifically, the wheel acceleration is calculated according to the following formula:

[0051] ;

[0052] in, is the wheel acceleration, is the time step, Indicates the current moment, For vehicle speed. for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the vehicle at the moment.

[0053] Step 1300: Based on the vehicle's motion state and the wheel acceleration, perform signal separation on the acceleration signal detected by the acceleration sensor to obtain the actual acceleration and slope of the vehicle.

[0054] Usually, vehicles are equipped with an inertial measurement unit (IMU). The IMU contains an accelerometer and a gyroscope. The acceleration it measures includes the actual acceleration and slope components used to reflect the actual movement changes of the vehicle. In order to ensure the accuracy of vehicle control, the actual acceleration and slope need to be separated. Figure 2 As shown, A_x is the acceleration sensor signal.

[0055] In this embodiment, step 1300 includes steps 1310-1330.

[0056] Step 1310: When the vehicle is moving, construct the vehicle's state equation and observation equation based on the wheel acceleration.

[0057] The state equation of the vehicle is:

[0058] ;

[0059] in, is the actual acceleration of the vehicle, is the wheel acceleration, is the acceleration due to gravity, is the slope angle, for The slope angle at the moment, for The slope angle at the moment, and is the process noise.

[0060] The vehicle's state equation is used to describe the vehicle's state changes. In the state equation, the relationship between the vehicle's actual acceleration and the calculated wheel acceleration and slope angle is reflected.

[0061] The observation equation is:

[0062] ;

[0063] in, is the observation vector, is the acceleration detected by the acceleration sensor, is the wheel acceleration, is the actual acceleration of the vehicle, is the acceleration due to gravity, is the slope angle, is the observation noise.

[0064] Step 1320: Based on the state equation of the vehicle and the observation equation, the acceleration signal detected by the acceleration sensor is separated by Kalman filtering to obtain the actual acceleration and slope of the vehicle.

[0065] The Kalman filter is an efficient recursive state estimation algorithm that achieves optimal estimation of the state of a dynamic system by fusing a system model with noisy observation data. During signal separation using the Kalman filter, the vehicle's state equation describes the dynamic changes in the vehicle's state and predicts the state at the next moment based on the physical model. The observation equation links sensor measurements with state variables, providing indirect observation of the state and addressing signal coupling issues.

[0066] is the observation matrix, which expresses how the acceleration sensor signal mixes the actual acceleration of the vehicle and the slope. The component of the acceleration due to gravity along the slope Superposition is performed and the observation noise is introduced to obtain the acceleration detected by the acceleration sensor. Wheel acceleration Only with the actual acceleration of the vehicle Correlation can provide independent information for signal decoupling. Through two independent observations, the Kalman filter can estimate the actual acceleration of the vehicle. and slope angle .

[0067] Step 1330: When the vehicle is stationary, determine that the actual acceleration of the vehicle is zero, and calculate the slope based on the acceleration signal detected by the acceleration sensor.

[0068] When the wheel speed is zero, the vehicle is confirmed to be stationary. When the vehicle is stationary, if the vehicle is on a horizontal surface, the actual acceleration of the vehicle If the vehicle is on a slope, the acceleration detected by the acceleration sensor is zero. is the acceleration due to gravity The slope can be calculated by taking the component along the slope surface.

[0069] The slope percentage is calculated according to the following formula:

[0070] ;

[0071] in, is the slope percentage.

[0072] In this embodiment, the method further includes: introducing a first-order delay model into the observation equation to correct the acceleration sensor signal delay.

[0073] ;

[0074] in, is the observation vector, is the delayed observation vector, is the delay time, is a complex frequency domain variable.

[0075] Accelerometer signals may experience delays due to various factors, such as CAN (Controller Area Network) bus transmission and IMU signal processing. The first-order delay model is used to describe the time lag effects of signal transmission or processing. Its core function is to quantify and compensate for signal delays to improve the accuracy of state estimation and control. By properly utilizing the first-order delay model, the real-time performance of state estimation and the robustness of control systems in vehicle dynamics systems can be significantly improved.

[0076] In this embodiment, step 1100 includes steps 1110-1130.

[0077] Step 1110: Under the acceleration condition, the average value of the wheel speeds of the non-driving wheels is used as the vehicle speed.

[0078] If the vehicle's driving wheels are the rear wheels, then the average of the two front wheel speeds is used as the vehicle speed. The speed calculation formula is as follows:

[0079] ;

[0080] in, is the speed of the left front wheel, is the speed of the right front wheel, For vehicle speed.

[0081] If the driving wheels of the vehicle are the front wheels, then the average of the wheel speeds of the two rear wheels is used as the vehicle speed. The vehicle speed calculation formula is as follows:

[0082] ;

[0083] in, is the speed of the left rear wheel, is the speed of the right rear wheel.

[0084] When the vehicle is accelerating, the average of the non-driving wheel speeds is used as the vehicle speed to avoid driving wheel slip interference and improve the accuracy of vehicle speed calculation.

[0085] Step 1120: Under braking conditions, the maximum value of the average value of the front wheel speed and the average value of the rear wheel speed is taken as the vehicle speed.

[0086] When the vehicle is in braking condition, the speed is calculated as follows:

[0087] ;

[0088] Calculate the average front wheel speed and the average rear wheel speed, then compare them. If the average front wheel speed is greater than the average rear wheel speed, use the average front wheel speed as the vehicle speed. If the average front wheel speed is less than the average rear wheel speed, use the average rear wheel speed as the vehicle speed.

[0089] Step 1130: Under other working conditions, the average of the wheel speeds of all wheels is used as the vehicle speed.

[0090] When the vehicle is in other working conditions, such as a constant speed condition, the speed calculation formula is as follows:

[0091] ;

[0092] The vehicle in the present invention is a four-wheel vehicle, so the vehicle speed under other working conditions is the average value of the wheel speeds of the four wheels.

[0093] In this embodiment, the method further includes: performing low-pass filtering on the vehicle speed signal using a second-order Butterworth filter. The second-order Butterworth filter is represented as follows:

[0094] ;

[0095] in, is the transfer function of the filter, is the cutoff frequency, is a complex frequency domain variable.

[0096] like Figure 3 As shown in the figure, during the speed calculation process, the vehicle state is first determined to determine the actual working condition of the vehicle. Then, the corresponding method is selected to calculate the speed according to the actual working condition of the vehicle, and then a second-order Butterworth filter is used for low-pass filtering. In actual applications, the cutoff frequency is selected according to the dynamic characteristics of the vehicle. For example, the cutoff frequency It can be 2Hz to suppress high frequency noise.

[0097] This invention significantly reduces signal coupling errors through condition-specific wheel speed processing and Kalman filtering. It also employs a five-point differential method to improve acceleration calculation accuracy and adapt to dynamic operating conditions. Low-pass filtering and delay compensation are also incorporated to effectively suppress noise and improve real-time performance.

[0098] This embodiment introduces an electronic device, including a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the program or instructions are executed by the processor, the steps of a method for separating vehicle acceleration and slope signals as described in any embodiment of the present invention are implemented.

[0099] This embodiment introduces a vehicle, including an electronic device described in the above embodiment of the present invention.

[0100] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention.

[0101] Those skilled in the art will appreciate that the modules and algorithm steps described in conjunction with the embodiments disclosed herein can be implemented using electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0102] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and equipment can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0103] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules 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, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0104] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of these modules may be selected according to actual needs to achieve the objectives of the embodiments of the present invention.

[0105] In addition, each functional module in the embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0106] If the functions are implemented in the form of software modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0107] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

[0108] It should be understood that the size of the serial numbers of the steps in the content of the invention and the embodiments of the present invention does not absolutely mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention. The foregoing description of the implementation of the present disclosure has been given for the purpose of example and description. The foregoing description is not exhaustive and is not intended to limit the present disclosure to the exact form disclosed. Various variations and modifications may exist based on the above teachings, or various variations and modifications may be obtained from the practice of the present disclosure. These embodiments are selected and described in order to illustrate the principles of the present disclosure and its practical application, so that those skilled in the art can utilize the present disclosure in various embodiments and various modifications suitable for the specific purpose conceived.

Claims

1. A method for separating vehicle acceleration and slope signals, characterized in that: include: Calculate vehicle speed based on actual vehicle operating conditions and wheel speed signals; Calculating wheel acceleration based on the vehicle speed using a five-point difference method; According to the motion state of the vehicle and the wheel acceleration, the acceleration signal detected by the acceleration sensor is separated to obtain the actual acceleration and slope of the vehicle.

2. The method according to claim 1, characterized in that The calculating of the wheel acceleration based on the vehicle speed using a five-point difference method includes: Calculate the wheel acceleration using the following formula: ； in, is the wheel acceleration, is the time step, Indicates the current moment, is the vehicle speed, for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the car at the moment, for The speed of the vehicle at the moment.

3. The method according to claim 1, characterized in that The step of performing signal separation on the acceleration signal detected by the acceleration sensor according to the vehicle's motion state and the wheel acceleration to obtain the actual acceleration and slope of the vehicle includes: When the vehicle is moving, constructing a state equation and an observation equation of the vehicle according to the wheel acceleration; Based on the state equation of the vehicle and the observation equation, performing signal separation on the acceleration signal detected by the acceleration sensor through Kalman filtering to obtain the actual acceleration and slope of the vehicle; When the vehicle is stationary, the actual acceleration of the vehicle is determined to be zero, and the slope is calculated based on the acceleration signal detected by the acceleration sensor.

4. The method according to claim 3, characterized in that The state equation of the vehicle is: ； in, is the actual acceleration of the vehicle, is the wheel acceleration, is the acceleration due to gravity, is the slope angle, for The slope angle at the moment, for The slope angle at the moment, and is the process noise.

5. The method according to claim 3, characterized in that The observation equation is: ； in, is the observation vector, is the acceleration detected by the acceleration sensor, is the wheel acceleration, is the actual acceleration of the vehicle, is the acceleration due to gravity, is the slope angle, is the observation noise.

6. The method according to claim 5, characterized in that The method further comprises: Introducing a first-order delay model into the observation equation to correct the acceleration sensor signal delay; ； in, is the observation vector, is the delayed observation vector, is the delay time, is a complex frequency domain variable.

7. The method according to claim 1, characterized in that The calculating of the vehicle speed according to the actual working condition of the vehicle and the wheel speed signal includes: Under acceleration conditions, the average of the non-driving wheel speeds is taken as the vehicle speed; Under braking conditions, the maximum value of the average of the front wheel speed and the average of the rear wheel speed is taken as the vehicle speed; Under other working conditions, the average of the wheel speeds of all wheels is taken as the vehicle speed.

8. The method according to claim 7, characterized in that The method further includes: performing low-pass filtering on the vehicle speed signal using a second-order Butterworth filter, wherein the second-order Butterworth filter is represented as follows: ； in, is the transfer function of the filter, is the cutoff frequency, is a complex frequency domain variable.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of a method for separating vehicle acceleration and slope signals as described in any one of claims 1 to 8 are implemented.

10. A vehicle, characterized in that: An electronic device comprising the electronic device described in claim 9.

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