Lateral acceleration control methods, computer systems and software products
By monitoring and controlling the vehicle's lateral acceleration, recording angle limits, and setting fixed angles, the problem of asymmetric lateral acceleration during vehicle cornering is solved, improving vehicle stability and safety and meeting regulatory requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2024-12-27
- Publication Date
- 2026-06-30
Smart Images
Figure CN122300477A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of vehicle control. More specifically, this application relates to a lateral acceleration control method aimed at improving vehicle driving stability and improving left-right symmetry when reaching maximum lateral acceleration. This application further relates to a computer system and a computer program product. Background Technology
[0002] Vehicles typically undergo a series of tests before being released to the market to meet regulatory and technical specifications. Lateral acceleration is one of the regulatory focuses. During testing and driving, differences may exist between the lateral acceleration when turning left and right. Such differences in lateral acceleration can be caused by zero-position deviations in the Electric Powered Steering (EPS) system. In EPS systems, due to a certain range of calibration error, the recorded driving angle when the vehicle is traveling straight may not necessarily be zero degrees, but may deviate by 0.1 to 2 degrees; for example, the recorded driving angle may be 1 degree or -1 degree. There is an ongoing need in the field for control of vehicle lateral acceleration, with the aim of reducing the difference between left and right lateral acceleration to meet regulatory requirements. Summary of the Invention
[0003] One objective of this application is to provide a lateral acceleration control method that provides smooth vehicle driving and cornering capabilities. Another objective of this application is to provide a computer system, a computer-readable storage medium, and a computer program product to implement the aforementioned lateral acceleration control method.
[0004] The objective of this application is achieved through the following technical solution: A lateral acceleration control method includes the following steps: Obtain the vehicle's lateral acceleration; Monitor whether the lateral acceleration exceeds a predetermined threshold; When the lateral acceleration is greater than a predetermined threshold, the vehicle's angle limit value is acquired and recorded based on the lateral acceleration. When the lateral acceleration is greater than the predetermined threshold for a predetermined time, the maximum angle is set to a fixed value in the controller.
[0005] A computer system includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-described lateral acceleration control method.
[0006] A computer program product includes a computer program that, when executed by a processor, implements the steps of the above-described lateral acceleration control method. Attached Figure Description
[0007] The present application will be further described in detail below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will appreciate that these drawings are drawn for the purpose of explaining the preferred embodiments only and therefore should not be construed as limiting the scope of the present application. Furthermore, unless specifically indicated, the drawings are intended only to conceptually represent the composition or structure of the described objects and may contain exaggerated representations. The drawings are also not necessarily drawn to scale.
[0008] Figure 1 This is a flowchart of one embodiment of the lateral acceleration control method of this application.
[0009] Figure 2 This is a flowchart of another embodiment of the lateral acceleration control method of this application. Detailed Implementation
[0010] Preferred embodiments of this application will now be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary and should not be construed as limiting the scope of protection of this application.
[0011] First, it should be noted that the directional terms such as top, bottom, upward, and downward mentioned in this article are defined relative to the directions shown in the various accompanying figures. These directions are relative concepts and will therefore vary depending on their location and state. Therefore, these or other directional terms should not be construed as restrictive.
[0012] Furthermore, it should be noted that any single technical feature described or implied in the embodiments herein, or any single technical feature shown or implied in the accompanying drawings, can be further combined to obtain other embodiments not directly mentioned herein.
[0013] It should be noted that in different figures, the same reference numerals indicate the same or substantially the same steps.
[0014] Figure 1 and Figure 2 Different embodiments of the lateral acceleration control method of this application are shown. According to one embodiment, the lateral acceleration control method of this application includes the following steps: acquiring the lateral acceleration of the vehicle; monitoring whether the lateral acceleration is greater than a predetermined threshold; when the lateral acceleration is greater than the predetermined threshold, acquiring and recording an angle limit value of the vehicle based on the lateral acceleration; and when the lateral acceleration is greater than the predetermined threshold and has lasted for a predetermined time, setting a maximum angle to a fixed value in the controller. In one embodiment, the angle limit value of the vehicle is further acquired after acquiring the lateral acceleration of the vehicle.
[0015] In one embodiment, the lateral acceleration control method of this application can be used for R79 regulatory testing of a vehicle. However, it should be understood that the lateral acceleration control method of this application can also be used for the daily operation control of a vehicle, and is therefore not limited to implementation in regulatory testing. R79 regulation refers to UN / ECE R79, the United Nations / Economic Commission for Europe R79 standard, which addresses various technical specifications for vehicle steering systems.
[0016] At step 100, the process begins according to an embodiment of the lateral acceleration control method of this application. It is readily understood that, although... Figure 1 and Figure 2 An embodiment of the lateral acceleration control method of this application is illustrated in a linear manner; however, the actual lateral acceleration control method may operate cyclically or in a closed loop. That is, an embodiment of the lateral acceleration control method of this application may operate continuously, for example, during vehicle operation or testing.
[0017] At step 200, the lateral acceleration of the vehicle is acquired. In one embodiment, the lateral acceleration can be acquired by an acceleration sensor on the vehicle. In another embodiment, the lateral acceleration can be calculated from the sensing results of a gyroscope on the vehicle. The raw lateral acceleration signal may include glitches or sudden, abrupt changes. Therefore, some degree of preprocessing of the raw signal is an option. In one embodiment, the lateral acceleration signal can be processed by a first-order low-pass filter to eliminate glitches in the lateral acceleration signal. In one embodiment, the first-order low-pass filter can be implemented by circuit elements, such as a combination of resistors and capacitors. In another embodiment, the first-order low-pass filter can be implemented in software, for example, by signal processing. Techniques for implementing first-order low-pass filters in software are known and will not be elaborated upon herein.
[0018] At step 300, the vehicle's angle limit value is obtained based on the vehicle's lateral acceleration. In one embodiment, the vehicle's angle limit value is obtained by looking up a table based on the vehicle's lateral acceleration. The table mentioned above can be a series of data stored in the vehicle's memory, which may be calibrated through testing before the vehicle leaves the factory and stored in the vehicle's memory in the form of a table. In one embodiment, the table can be a 16-axis speed interpolation table. In one embodiment, an initial angle limit is obtained by looking up the table.
[0019] At step 400, the lateral acceleration of the vehicle is monitored. Specifically, monitoring the lateral acceleration includes checking whether the vehicle's lateral acceleration exceeds a predetermined threshold and whether the time during which the vehicle's lateral acceleration exceeds the predetermined threshold exceeds a predetermined time. In one embodiment, the predetermined threshold can be determined according to regulations or standards used for vehicle testing. In one embodiment, the predetermined threshold can be determined according to the requirements of Regulation R79. For example, section 5.6.2.1.3 of Regulation R79 Version 5 specifies a maximum and minimum value for a specific maximum lateral acceleration for M1 and N1 category vehicles. In one embodiment, a value between the aforementioned maximum and minimum values can be set as the predetermined threshold. For example, the maximum value of the specific maximum lateral acceleration, the minimum value of the specific maximum lateral acceleration, or a value between the aforementioned maximum and minimum values, such as an average value, can be selected. The predetermined time can be any suitable time length. In one embodiment, the predetermined time can be between two and four frames, such as three frames. A frame refers to the time interval between the acceleration sensor sending sensing results, such as 10 milliseconds. In one embodiment, the predetermined time can be the time length from receiving two to four sensing results from the acceleration sensor, such as the time length for receiving three sensing results. In one embodiment, the predetermined time can be set to the CAN message period or a fixed time length, such as 30 milliseconds. Setting a predetermined time can effectively filter signal glitches and reduce the occurrence of misjudgments. It is readily understood that the lateral acceleration control method described in this application can be executed on a vehicle with a CAN (Controller Area Network) bus, and therefore, a vehicle with a CAN bus can provide CAN messages to report and monitor the vehicle status in real time. The CAN message can have a predetermined message period, for example, a CAN message is sent once every 30 milliseconds. The CAN message can contain several nodes, such as the EPS (Electric Power Steering) node mentioned below.
[0020] After the judgment at step 400, two different paths are executed. Figure 1 The path marked N on the left represents the case where the judgment at step 400 is "No". That is, the lateral acceleration is not greater than the predetermined threshold, or the time when the lateral acceleration is greater than the predetermined threshold does not last for the predetermined time. Figure 1 The path marked Y on the right represents the case where the judgment at step 400 is "yes". That is, the lateral acceleration is greater than a predetermined threshold, and the time during which the lateral acceleration is greater than the predetermined threshold continues to exceed a predetermined time.
[0021] At step 500, in the controller, the vehicle's angle limit value is set to a fixed value or a fixed number. In one embodiment, the angle limit value can be one of the following: the steering wheel angle from the EPS node in a CAN message received within a predetermined time period; the first of multiple angle limit values / real-time vehicle angles recorded within a predetermined time period; the last of multiple angle limit values / real-time vehicle angles recorded within a predetermined time period; the average of multiple angle limit values / real-time vehicle angles recorded within a predetermined time period; the maximum of multiple angle limit values / real-time vehicle angles recorded within a predetermined time period; or the minimum of multiple angle limit values / real-time vehicle angles recorded within a predetermined time period. In one embodiment, the vehicle's real-time angle in frames within the predetermined time period can be recorded and set as the angle limit value. In one embodiment, the controller can be a controller in an onboard camera. In one embodiment, the controller can be a controller in an onboard radar. In one embodiment, the controller can be another controller on the vehicle.
[0022] At step 600, the lateral acceleration control method according to one embodiment of this application ends. It is readily understood that one embodiment of the lateral acceleration control method of this application can operate cyclically, in a closed loop, or periodically to continuously monitor the vehicle's status.
[0023] Figure 2 Another embodiment of the lateral acceleration control method of this application is shown. Steps 100, 200, and 600 are substantially the same as described above. In step 700, it is monitored whether the lateral acceleration is greater than a predetermined threshold and whether the vehicle deviates from the lane.
[0024] Figure 2 The path marked N on the left represents the case where the judgment at step 700 is "No". That is, the lateral acceleration did not exceed the predetermined threshold, or the vehicle did not deviate from the lane. Figure 2 The path marked Y on the right represents the case where the judgment at step 700 is "yes". That is, the lateral acceleration is greater than the predetermined threshold and the vehicle deviates from the lane.
[0025] At step 800, suppression is applied to the Lane Keeping Assist (LKA) system and / or Traffic Jam Assist (TJA) system. In one embodiment, the lane keeping system is preferentially restricted at relatively low vehicle speeds. In one embodiment, a relatively low vehicle speed may be below 60 km / h. In one embodiment, a relatively high vehicle speed may be above 60 km / h. Restricting the aforementioned systems can effectively reduce undesirable changes in lateral acceleration, thereby improving system stability. In one embodiment, the controller described at step 500 is also the controller performing the lane keeping and / or traffic jam assist functions.
[0026] The technical solution presented in this application has the advantages of simplicity, reliability, ease of implementation, and convenient use. It can effectively reduce abnormal lateral acceleration in vehicles, thereby improving driving safety. The technical solution of this application can well meet the requirements of vehicle regulations or standards, such as the requirements of the R79 regulation. The vehicle no longer requires additional four-wheel calibration and zero-position calibration, thus reducing overall costs.
[0027] This application also relates to a computer system including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the lateral acceleration control method described above. In one embodiment, the processor may be a vehicle control unit. In one embodiment, the memory may be a memory located in the vehicle.
[0028] This application also relates to a computer program product, including a computer program, wherein when executed by a processor, the computer program implements the steps of the above-described lateral acceleration control method. In one embodiment, the processor may be a vehicle control unit.
[0029] This specification discloses the present application with reference to the accompanying drawings, and also enables those skilled in the art to implement the application, including making and using any device or system, selecting suitable materials, and using any combination method. The scope of this application is defined by the claimed technical solution, but includes other instances that would occur to those skilled in the art. Such other instances shall be considered to fall within the scope of protection defined by the claimed technical solution, provided that they include structural elements that are not different from the literal language of the claimed technical solution, or that they include equivalent structural elements that are not substantially different from the literal language of the claimed technical solution.
Claims
1. A transverse acceleration control method characterized by, Includes the following steps: Obtain the vehicle's lateral acceleration; Monitor whether the lateral acceleration is greater than a predetermined threshold; When the lateral acceleration is greater than the predetermined threshold, the angle limit value of the vehicle is obtained and recorded based on the lateral acceleration, and when the lateral acceleration is greater than the predetermined threshold for a predetermined time, the maximum angle is set to a fixed value in the controller.
2. The lateral acceleration control method according to claim 1, characterized by, The lateral acceleration is obtained by an accelerometer or gyroscope, and the lateral acceleration signal is processed by a first-order low-pass filter.
3. The lateral acceleration control method according to claim 1, characterized by, The angle limit value is obtained by looking up a table configured to represent the relationship between the vehicle's lateral acceleration and the vehicle's angle limit value, and is calibrated before leaving the factory.
4. The lateral acceleration control method according to claim 1, characterized in that, The predetermined threshold is determined based on the maximum and minimum values of a specific maximum lateral acceleration value as specified in Regulation R79.
5. The lateral acceleration control method according to claim 1, characterized in that, The predetermined time is set to one of the following: two to four frames, where a frame is the time interval between the accelerometer sending the sensing results; the time required to receive two to four sensing results from the accelerometer; or the CAN message period.
6. The lateral acceleration control method according to claim 5, characterized in that, The fixed value is set to one of the following: the steering wheel angle sent from the EPS node in the CAN message received within the predetermined time, the first of multiple angle limit values / real-time vehicle angles recorded within the predetermined time, the last of multiple angle limit values / real-time vehicle angles recorded within the predetermined time, the average of multiple angle limit values / real-time vehicle angles recorded within the predetermined time, the maximum of multiple angle limit values / real-time vehicle angles recorded within the predetermined time, and the minimum of multiple angle limit values / real-time vehicle angles recorded within the predetermined time.
7. The lateral acceleration control method according to any one of claims 1-6, characterized in that, Includes the following steps: When the lateral acceleration exceeds the predetermined threshold and the vehicle deviates from its lane, suppression is applied to the lane keeping system and / or traffic jam assist system.
8. The lateral acceleration control method according to any one of claims 1-6, characterized in that, The lateral acceleration control method is a closed loop and operates continuously in a cyclical manner.
9. A computer system comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the lateral acceleration control method according to any one of claims 1-8.
10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the lateral acceleration control method according to any one of claims 1-8.