Method and device for determining yawing moment, electronic equipment and storage medium

Abstract

The invention discloses a yaw moment determination method and device, electronic equipment and a storage medium, and relates to the technical field of vehicle control, the method pre-constructs a numerical relationship among a virtual steering transmission ratio, a steering wheel angle and an additional yaw moment, and uses the virtual steering transmission ratio to closely associate the steering wheel angle with the additional yaw moment, so as to determine the yaw moment. Therefore, the steering wheel flexibility degree currently required by the vehicle is introduced into the determination of the yawing moment, that is, the additional yawing moment needing to be actively applied when the vehicle performs steering response to a certain steering wheel rotation angle in the target steering mode is determined by utilizing the numerical relationship among the virtual steering transmission ratio, the steering wheel rotation angle and the additional yawing moment. In this way, the actual yawing motion of the vehicle under the action of the additional yawing moment corresponds to the flexibility of the steering wheel, and the maneuverability and stability of the whole vehicle are improved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a method, device, electronic equipment and storage medium for determining a yaw moment. Background Art

[0002] At present, the common way to calculate the yaw moment is to construct the required yaw rate target, and use the yaw rate target and the constructed control model to calculate the required yaw moment, that is, the additional yaw moment applied to the vehicle. However, there is a nonlinear relationship between the yaw rate and the steering wheel angle, and it is even affected by many other variables. Therefore, when adjusting the yaw moment by analyzing the yaw rate, the change in the yaw moment can only be roughly reflected in the steering wheel sensitivity, resulting in low maneuverability and stability of the vehicle. Summary of the invention

[0003] The embodiments of the present invention provide a method, device, electronic device and storage medium for determining a yaw moment, so as to solve the problem that the change of the yaw moment can only be roughly reflected in the sensitivity of the steering wheel, resulting in low maneuverability and stability of the whole vehicle.

[0004] A method for determining a yaw moment, the method comprising: Obtaining a steering wheel angle of a vehicle, and obtaining a virtual steering transmission ratio required by the vehicle in a target steering mode; Determine the additional yaw moment corresponding to the virtual steering transmission ratio and the steering wheel angle by using a preset conversion relationship; using the additional yaw moment as a yaw moment compensated when the vehicle performs steering in response to the steering wheel angle in the target steering mode; The preset conversion relationship includes a numerical relationship between a virtual steering gear ratio, a steering wheel angle and an additional yaw moment.

[0005] In one embodiment, the target steering mode includes an adaptive mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Get vehicle status; According to the vehicle state, the actual steering gear ratio of the vehicle is adaptively adjusted to determine the virtual steering gear ratio required by the vehicle in the adaptive mode.

[0006] In one embodiment, the target steering mode includes a custom mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Obtain the steering sensitivity selected by the user in the custom mode; The virtual steering transmission ratio corresponding to the steering sensitivity is used as the virtual steering transmission ratio required by the vehicle in the custom mode.

[0007] In one embodiment, the target steering mode includes a custom mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Obtain the steering sensitivity selected by the user in the custom mode; Get vehicle status; According to the vehicle state, the virtual steering transmission ratio corresponding to the steering sensitivity is adaptively adjusted to determine the virtual steering transmission ratio required by the vehicle in the custom mode.

[0008] In one embodiment, a preset state quantity is used to characterize the vehicle state; The preset state quantity includes at least one of the following: vehicle speed, yaw angular velocity, lateral acceleration, and maximum adhesion coefficient.

[0009] In one embodiment, after determining the additional yaw moment corresponding to the virtual steering transmission ratio and the steering wheel angle by using a preset conversion relationship, the method further includes: The determined additional yaw moment is corrected by using a pre-calibrated additional yaw moment implementation error to obtain a final additional yaw moment, wherein the additional yaw moment implementation error is a difference between a theoretical value and a measured value of the additional yaw moment.

[0010] In one embodiment, the numerical relationship is determined in the following manner: Determine an equation between a wheel angle change and an additional yaw moment simulation applied to the vehicle model, wherein the wheel angle change is a wheel angle change of a wheel corresponding to the steering wheel before and after the additional yaw moment simulation is applied when the vehicle model reaches a fixed yaw angular velocity; The virtual steering gear ratio is characterized by the ratio between the target steering angle and the steering wheel angle, so as to extract the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment simulation from the equation, wherein the target steering angle is the steering angle of the wheel corresponding to the steering wheel before the additional yaw moment simulation is applied.

[0011] A device for determining a yaw moment, the device comprising: an acquisition module, used to acquire a steering wheel angle of a vehicle, and to acquire a virtual steering gear ratio required by the vehicle in a target steering mode; a determination module, used to determine an additional yaw moment corresponding to both the virtual steering gear ratio and the steering wheel angle by using a preset conversion relationship; using the additional yaw moment as the yaw moment compensated when the vehicle implements steering in response to the steering wheel angle in the target steering mode; the preset conversion relationship comprises a numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment.

[0012] In one embodiment, the target steering mode includes an adaptive mode, and the acquisition module is used to: acquire a vehicle state; and adaptively adjust an actual steering transmission ratio of the vehicle according to the vehicle state to determine a virtual steering transmission ratio required by the vehicle in the adaptive mode.

[0013] In one embodiment, the target steering mode includes a custom mode, and the acquisition module is used to: obtain the steering sensitivity selected by the user in the custom mode; and use the virtual steering transmission ratio corresponding to the steering sensitivity as the virtual steering transmission ratio required by the vehicle in the custom mode.

[0014] In one embodiment, the target steering mode includes a custom mode, and the acquisition module is used to: obtain the steering sensitivity selected by the user in the custom mode; obtain the vehicle state; and adaptively adjust the virtual steering transmission ratio corresponding to the steering sensitivity according to the vehicle state to determine the virtual steering transmission ratio required for the vehicle in the custom mode.

[0015] In one embodiment, a preset state quantity is used to characterize the vehicle state; the preset state quantity includes at least one of the following: vehicle speed, yaw angular velocity, lateral acceleration, and maximum adhesion coefficient.

[0016] In one embodiment, the determination module is further used to: use a pre-calibrated additional yaw moment implementation error to correct the determined additional yaw moment to obtain a final additional yaw moment, and the additional yaw moment implementation error is the difference between a theoretical value and a measured value of the additional yaw moment.

[0017] In one embodiment, the device is also used to determine the numerical relationship in the following manner: determine an equation between the wheel angle change and the additional yaw moment simulation applied to the vehicle model, the wheel angle change being the angle change of the wheel corresponding to the steering wheel before and after the additional yaw moment simulation is applied when the vehicle model reaches a fixed yaw angular velocity; use the ratio between the target angle and the steering wheel angle to characterize the virtual steering transmission ratio, so as to extract the numerical relationship between the virtual steering transmission ratio, the steering wheel angle, and the additional yaw moment simulation from the equation, the target angle being the angle of the wheel corresponding to the steering wheel before the additional yaw moment simulation is applied.

[0018] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the method for determining the yaw moment described in any one of the above embodiments when executing the computer program.

[0019] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for determining the yaw moment described in any one of the above embodiments is implemented.

[0020] The above-mentioned method, device, electronic device and storage medium for determining the yaw moment, the change of the steering gear ratio of the vehicle will directly affect the sensitivity of the steering wheel. The present invention proposes a virtual steering gear ratio, which uses the virtual steering gear ratio to introduce the steering wheel flexibility required by the vehicle into the determination of the yaw moment, that is, the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment is used to determine the yaw moment that needs to be actively added when the vehicle responds to a certain steering wheel angle in the target steering mode. In this way, the actual yaw motion of the vehicle under the action of the additional yaw moment is closely related to the steering wheel flexibility, thereby improving the maneuverability and stability of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0022] Figure 1 is a flow chart of a method for determining yaw moment in one embodiment of the present invention; Figure 2 is another flow chart of a method for determining a yaw moment in one embodiment of the present invention; Figure 3is another flow chart of a method for determining a yaw moment in one embodiment of the present invention; Figure 4 is a schematic diagram of a slider bar used when a user selects steering sensitivity in a custom mode in one embodiment of the present invention; Figure 5 is another flow chart of a method for determining a yaw moment in one embodiment of the present invention; Figure 6 is another flow chart of a method for determining a yaw moment in one embodiment of the present invention; Figure 7 is a comparative schematic diagram of a yaw angular velocity variation curve in one embodiment of the present invention; Figure 8 is a schematic block diagram of a device for determining a yaw moment in one embodiment of the present invention; Fig. 9 is a schematic block diagram of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, but does not exclude the presence or addition of one or more other features, integers, steps, operations and / or groups thereof.

[0025] It should also be understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0026] References to "one embodiment" or "some embodiments" etc. described in the present specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appearing in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0027] It is important to understand that during vehicle driving, especially when turning or encountering external disturbances such as lateral wind, the vehicle will generate lateral forces and moments, causing the vehicle body to roll, thereby generating the original yaw moment. However, in some cases, such as when the vehicle is understeering or oversteering, driving on slippery or low-adhesion roads, driving at high speeds or avoiding obstacles in an emergency, in order to maintain the stability and safety of the vehicle, it is necessary to actively apply an additional yaw moment to the vehicle.

[0028] This additional yaw moment is achieved by adjusting the driving force or braking force of the wheels. It will superimpose an additional torque on the original yaw moment of the vehicle to change the yaw rate and driving trajectory of the vehicle. For example, when the vehicle is understeering, braking force will be applied to the inner wheel or driving force will be applied to the outer wheel to generate an additional yaw moment in the same direction as the original yaw direction of the vehicle; when the vehicle is oversteering, the opposite measures will be taken to generate an additional yaw moment in the opposite direction of the original yaw direction of the vehicle.

[0029] It should be noted that the method for determining the yaw moment provided in the embodiment of the present invention can be applied to intelligent driving vehicles, for example, it can be applied to vehicles in the form of single-axis distributed drive or four-wheel independent drive, and is used to determine the value of the additional yaw moment that needs to be actively applied to the vehicle. The yaw response characteristics of the vehicle are changed by applying the additional yaw moment. When the vehicle is turning, the additional yaw moment actively applied to the vehicle is adjusted to a value that matches the current steering mode, the steering wheel angle and the additional yaw moment are closely related, and the change in the steering wheel sensitivity is closely related to the change in the yaw motion trajectory, thereby improving the maneuverability and stability of the vehicle.

[0030] Figure 1 is a flow chart of a method for determining yaw moment in one embodiment of the present invention.

[0031] like Figure 1 As shown, the method for determining the yaw moment provided by the present invention may include the following steps: S101, obtaining a steering wheel angle of a vehicle, and obtaining a virtual steering transmission ratio required by the vehicle in a target steering mode.

[0032] The steering wheel angle of a vehicle can be understood as the angle at which the steering wheel rotates in real time while the vehicle is driving.

[0033] In this embodiment, each steering mode may correspond to a plurality of steering styles. It can be understood that there are a plurality of selectable steering styles in each steering mode, and each steering style may correspond to a virtual steering transmission ratio. For example, the steering styles may include steady, sensitive, and the like.

[0034] When the vehicle achieves the same yaw motion, the virtual steering transmission ratio corresponding to the sensitive steering style is greater than the virtual steering transmission ratio corresponding to the steady steering style; correspondingly, the steering wheel angle under the sensitive steering style is smaller than the steering wheel angle under the steady steering style.

[0035] The steering mode may understand the selection / switching method of the steering style. For example, the steering mode may include a custom mode and / or an adaptive mode. The steering mode or steering sensitivity of the vehicle may be customized by the user or the vehicle may adaptively select the vehicle.

[0036] In practice, the vehicle's steering system has an actual steering ratio. The steering ratio refers to the proportional relationship between the steering angle of the steering wheel and the steering angle of the wheels. Specifically, when the steering wheel turns a certain angle, the wheels will also turn a certain angle accordingly. The ratio between these two angles is the steering ratio.

[0037] This embodiment proposes a virtual steering transmission ratio, introduces the steering wheel angle into the determination of the yaw moment, and closely associates the steering wheel angle with the yaw moment.

[0038] For a certain steering wheel angle, the steering wheel angle is converted into front wheel angle A through the actual steering transmission ratio, and is converted into front wheel angle B through the virtual steering transmission ratio. When the virtual steering transmission ratio and the actual steering transmission ratio are different, the front wheel angles corresponding to the same steering wheel angle are not the same. In order to compensate for the difference in front wheel angles, additional yaw torque needs to be applied to the vehicle to improve the understeer problem caused by the front wheel angle A not reaching the front wheel angle B, or to improve the oversteer problem caused by the front wheel angle A being greater than the front wheel angle B.

[0039] In this way, when the user operates the steering wheel to turn the same angle, under the sensitive steering style, the virtual steering transmission is relatively large, and the understeering of the vehicle under the actual steering transmission ratio can be compensated by applying an additional yaw torque in the same direction as the original yaw direction of the vehicle to the vehicle; under the steady steering style, the virtual steering transmission is relatively small, and the oversteering of the vehicle under the actual steering transmission ratio can be improved by applying an additional yaw torque in the opposite direction to the original yaw direction of the vehicle to the vehicle.

[0040] S102, using a preset conversion relationship, determining an additional yaw moment corresponding to the virtual steering gear ratio and the steering wheel angle; using the additional yaw moment as the yaw moment compensated when the vehicle responds to the steering wheel angle to turn in the target steering mode; the preset conversion relationship includes a numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment.

[0041] The present embodiment pre-constructs the conversion relationship of various parameters, which may include but is not limited to the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment. The numerical relationship can be expressed by an equation with the virtual steering gear ratio, the steering wheel angle and the additional yaw moment as variables.

[0042] Alternatively, the numerical relationship may also be directly expressed in the form of a numerical table. For example, the corresponding relationship between different virtual steering transmission ratios, different steering wheel angles and different additional yaw moments may be directly pre-calibrated and stored.

[0043] In this embodiment, the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment is used to determine the additional yaw moment corresponding to the virtual steering gear ratio required by the vehicle and the steering wheel angle of the vehicle. When the vehicle controls the vehicle body to perform steering in response to the steering wheel angle in the target steering mode, the value of the additional yaw moment is used as the yaw moment for active compensation, or is understood as the additional yaw moment actively applied by the vehicle.

[0044] The method for determining the yaw moment proposed in this embodiment pre-constructs the numerical relationship between the virtual steering transmission ratio, the steering wheel angle, and the additional yaw moment, and closely associates the steering wheel angle and the additional yaw moment by using the virtual steering transmission ratio, thereby introducing the steering wheel flexibility currently required by the vehicle into the determination of the yaw moment, that is, using the numerical relationship between the virtual steering transmission ratio, the steering wheel angle, and the additional yaw moment, the additional yaw moment that needs to be actively applied when the vehicle makes a steering response to a certain steering wheel angle in the target steering mode is determined. In this way, the actual yaw motion of the vehicle under the action of the additional yaw moment is matched with the steering wheel flexibility, thereby improving the maneuverability and stability of the whole vehicle.

[0045] Based on the above embodiment, the user can select a target steering mode from a variety of steering modes as needed. If the target steering mode includes an adaptive mode, Figure 2 As shown, in the above step S101, "obtaining the virtual steering transmission ratio required by the vehicle in the target steering mode" may include the following steps: S201, obtaining vehicle status; S202: Adaptively adjust the actual steering transmission ratio of the vehicle according to the vehicle state to determine a virtual steering transmission ratio required by the vehicle in the adaptive mode.

[0046] In this embodiment, the vehicle status may include the vehicle driving status, the road conditions on which the vehicle is driving, etc., which is not limited in this application.

[0047] For example, the vehicle subsystems / operating conditions that need to be paid attention to during the vehicle steering process can be pre-set as the vehicle state that this embodiment pays attention to. The vehicle state is used to determine whether the vehicle needs to ensure steering stability when steering in the current state, or whether the steering sensitivity can be appropriately increased.

[0048] For example, to ensure stability, the transmission ratio can be adjusted in the direction of decreasing, that is, the determined virtual steering transmission ratio is smaller than the actual steering transmission ratio of the vehicle; if sensitivity is to be improved, the transmission ratio can be adjusted in the direction of increasing, that is, the determined virtual steering transmission ratio is larger than the actual steering transmission ratio of the vehicle.

[0049] After determining the adjustment direction according to the vehicle state, the numerical value can be reduced or superimposed on the basis of the actual steering transmission ratio according to the preset step size to obtain a virtual steering transmission ratio; or the vehicle state can be quantified into a numerical value, and the pre-constructed correspondence between the vehicle state and the adjustment coefficient can be used to determine the adjustment coefficient corresponding to the current vehicle state.

[0050] It should be noted that there are other ways to adaptively adjust the actual steering transmission ratio of the vehicle according to the vehicle state, and this application does not limit it.

[0051] In this embodiment, based on the actual steering transmission ratio, the value of the actual steering transmission ratio is adaptively adjusted according to the change of the vehicle state, and the adjusted value is used as the virtual steering transmission ratio, so that the vehicle can adaptively determine the virtual steering transmission ratio currently required by the vehicle in combination with the vehicle state during driving, and adaptively adjust the steering style that fits the current vehicle state for the driver, that is, adaptively adjust the steering sensitivity of the steering wheel.

[0052] For example, at high speeds, reducing steering sensitivity can ensure driving safety; in narrow streets, parking lots, or road conditions that require frequent turning, increasing steering sensitivity can make the vehicle more flexible, easier for the driver to control, and reduce the risk of collision.

[0053] Therefore, this embodiment can apply the adaptive switching of steering styles to various scenarios by changing the content included in the vehicle state, thereby improving the overall performance of the vehicle and enhancing the user experience.

[0054] Based on the above embodiment, in addition to the above Figure 2 The method for obtaining the virtual steering transmission ratio shown in FIG. 1 can also be used to obtain the virtual steering transmission ratio in the following manner.

[0055] like Figure 3 As shown, if the target steering mode includes a custom mode, then the step S101 of "obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode" may include the following steps: S301, obtaining the steering sensitivity selected by the user in the custom mode; S302: Using the virtual steering transmission ratio corresponding to the steering sensitivity as the virtual steering transmission ratio required by the vehicle in the custom mode.

[0056] In custom mode, users such as the driver or passengers can independently select the steering sensitivity of the steering wheel. The steering sensitivity here is equivalent to the steering style mentioned above, and different steering styles correspond to different steering sensitivities.

[0057] For example, the vehicle computer interaction system displays Figure 4 The slider shown in the figure has one end corresponding to the minimum virtual steering gear ratio, the lowest steering sensitivity, and the most stable steering style; while the other end of the slider corresponds to the maximum virtual steering gear ratio, the highest steering sensitivity, and the most flexible steering style. The driver can manually move the slider on the slider through the vehicle-computer interaction system to select the desired steering sensitivity between the highest steering sensitivity and the lowest steering sensitivity.

[0058] It should be noted that the user may select steering sensitivity in various ways, including voice input, terminal selection, etc., which are not limited in this application.

[0059] In this embodiment, a mapping relationship between steering sensitivity and virtual steering gear ratio may be constructed in advance. After the steering sensitivity selected by the user is determined, the virtual steering gear ratio corresponding to the steering sensitivity selected by the user is used as the virtual steering gear ratio required by the vehicle in the above step S101.

[0060] This implementation provides a way for users to customize steering sensitivity. The virtual steering gear ratio corresponding to the steering sensitivity selected by the user is used as the virtual steering gear ratio referenced by the vehicle when determining the additional yaw moment, so that the yaw response characteristics of the vehicle when turning can accurately fit the steering style desired by the user.

[0061] Based on the above embodiment, in addition to Figure 2 and Figure 3 In addition to the method for obtaining the virtual steering transmission ratio shown, the virtual steering transmission ratio can also be obtained by the following method.

[0062] like Figure 5 As shown, the above step S101 of "obtaining the virtual steering transmission ratio required by the vehicle in the target steering mode" may include the following steps: S501, obtaining the steering sensitivity selected by the user in the custom mode; S502, obtaining vehicle status; S503: Adaptively adjust the virtual steering transmission ratio corresponding to the steering sensitivity according to the vehicle state to determine the virtual steering transmission ratio required by the vehicle in the custom mode.

[0063] In this embodiment, the specific implementation of step S501 can refer to the description of step S301, and the specific implementation of step S502 can refer to the description of step S201, which will not be repeated here.

[0064] After determining the steering sensitivity selected by the user, this embodiment can further adaptively adjust the virtual steering transmission ratio corresponding to the steering sensitivity. The method of adjusting the virtual steering transmission ratio can refer to the description of the method of adjusting the actual steering transmission ratio in the above step S202, which will not be repeated here.

[0065] In this embodiment, the virtual steering transmission ratio required by the user is corrected in combination with the actual vehicle state, so as to prevent the referenced virtual steering transmission ratio from not matching the vehicle state when the additional yaw moment is determined, thereby affecting driving safety.

[0066] For example, the maximum virtual steering gear ratio that the vehicle can provide can be determined according to the vehicle state, and if the virtual steering gear ratio required by the user is greater than the maximum virtual steering gear ratio, the virtual steering gear ratio is used as the virtual steering gear ratio required by the vehicle in the custom mode. Alternatively, the virtual steering gear ratio required by the user can be reduced or increased according to the vehicle state.

[0067] In this embodiment, based on the virtual steering transmission ratio required by the user, further adaptive adjustment is performed according to the vehicle state, so that the virtual steering transmission ratio finally determined can take into account the steering sensitivity desired by the user and can adapt to the vehicle state.

[0068] Based on the above embodiment, the "vehicle state" in each of the above steps can be represented by a preset state quantity. The preset state quantity may include but is not limited to at least one of the following: vehicle speed, yaw rate, lateral acceleration, maximum adhesion coefficient, etc.

[0069] For example, when the virtual steering gear ratio corresponding to the actual steering gear ratio / steering sensitivity is adaptively adjusted according to the vehicle state, if the vehicle speed is too high, the adjustment direction is determined to be reduced, and if the vehicle speed is below a certain limit, the adjustment direction is determined to be increased. Alternatively, if the maximum adhesion coefficient is greater than a certain limit, the adjustment direction is determined to be increased, and if the maximum adhesion coefficient is less than a certain limit, the adjustment direction is determined to be reduced.

[0070] For another example, when the vehicle speed is too high, the lateral acceleration is too large, and the maximum adhesion coefficient is low, it is not suitable to set a virtual steering transmission ratio that is too small. If the virtual steering transmission ratio set by the user or adaptively calculated is too small, it is necessary to appropriately increase the virtual steering transmission ratio to ensure that the vehicle has sufficient stability.

[0071] Vehicle speed, yaw angular velocity, lateral acceleration and maximum adhesion coefficient are important parameters that affect steering safety when the vehicle is turning. This embodiment uses these preset state quantities to characterize the vehicle state, which facilitates quantification of the relationship between the vehicle state and the virtual steering transmission ratio, so as to more accurately and meticulously determine the appropriate virtual steering transmission ratio for the vehicle state.

[0072] On the basis of the above embodiment, in the above step S102, after "using a preset conversion relationship to determine the additional yaw moment corresponding to the virtual steering gear ratio and the steering wheel angle", the following steps may also be included: The determined additional yaw moment is corrected by using a pre-calibrated additional yaw moment implementation error to obtain a final additional yaw moment, wherein the additional yaw moment implementation error is a difference between a theoretical value and a measured value of the additional yaw moment.

[0073] In practice, there is a certain error between the theoretical value of the additional yaw moment determined by the processing unit and the additional yaw moment actually applied to the vehicle. The magnitude of the error will vary depending on the vehicle model.

[0074] In this embodiment, for a certain vehicle type, the difference between the theoretical value and the measured value of the additional yaw moment may be pre-calibrated as the additional yaw moment implementation error.

[0075] After the additional yaw moment is determined in the above embodiment, the error is corrected using the additional yaw moment to obtain the final additional yaw moment, which is applied to the vehicle, so that the additional yaw moment actually applied to the vehicle reaches the additional yaw moment actually required by the vehicle.

[0076] When the final additional yaw moment is applied, the final additional yaw moment is converted into a change in output torque of each motor, and superimposed with the current motor drive torque calculated according to the accelerator pedal position to obtain a target torque that each motor needs to execute.

[0077] Based on the above embodiments, Figure 6 As shown, the present invention can determine the numerical relationship in the following manner: S601, determining an equation between a wheel angle change and an additional yaw moment simulation applied to the vehicle model, wherein the wheel angle change is a wheel angle change of a wheel corresponding to a steering wheel before and after the additional yaw moment simulation is applied when the vehicle model reaches a fixed yaw angular velocity; S602, using the ratio between the target angle and the steering wheel angle to characterize the virtual steering gear ratio, so as to extract the numerical relationship between the virtual steering gear ratio, the steering wheel angle, and the additional yaw moment simulation from the equation, wherein the target angle is the angle of the wheel corresponding to the steering wheel before the additional yaw moment simulation is applied.

[0078] The steering wheel angle in step S602 may be: after the additional yaw moment simulation is applied to the vehicle model, the steering wheel angle when the vehicle model reaches a fixed yaw angular velocity.

[0079] Based on the single-track two-degree-of-freedom vehicle model, the following analysis can be carried out: When the vehicle model reaches the same yaw rate, the change in the front wheel angle before and after the additional yaw moment simulation is applied to the vehicle model. The front wheel can be used as the wheel corresponding to the steering wheel mentioned above, and rotates as the steering wheel turns.

[0080] After analysis, the following equation can be extracted: in, It is the front wheel turning angle when the vehicle model reaches a fixed yaw angular velocity after the vehicle model applies the additional yaw moment simulation; is the front wheel turning angle required for the vehicle model to reach the above-mentioned fixed yaw angular velocity before applying the additional yaw moment simulation to the vehicle model; is the wheelbase of the vehicle model; is the additional yaw moment analog; , are the sideslip stiffness of the front and rear axles of the vehicle model respectively.

[0081] by Represents the actual steering gear ratio of the vehicle model; Indicates that the vehicle model has a front wheel turning angle of When the steering wheel angle is When the front wheel angle reaches Required virtual steering ratio ; Then the above equation can be written as: Then, for a given virtual steering gear ratio, the yaw moment value that needs to be added to the original vehicle can be calculated using this equation: The present invention starts from the operation of the steering wheel and, according to the derivation of the vehicle dynamics equation, the difference in the front wheel turning angle required to achieve a certain yaw angular velocity when there is an additional yaw moment and when there is no additional yaw moment. With the help of the definition of a virtual steering transmission ratio, the different front wheel turning angles corresponding to the presence or absence of the additional yaw moment are converted into the same steering wheel input, thereby obtaining a method for calculating the required additional yaw moment for a given virtual steering transmission ratio.

[0082] Figure 7 It is the simulation effect based on the multi-body model of the whole vehicle, Figure 7 It is the simulation result obtained when the virtual steering gear ratio is fixed.

[0083] By setting the virtual steering ratio, the yaw motion of the original vehicle can be made close to the yaw motion effect brought by the desired steering ratio by adding yaw torque. It is even possible to simulate the effect of changing the steering ratio of the original vehicle by dynamically changing the virtual steering ratio.

[0084] For example, Figure 7 , the solid line at the bottom of the image is the curve of the yaw rate changing with time when the steering gear ratio of the original vehicle is 15.6, the solid line at the top of the image is the curve of the yaw rate changing with time when the expected steering gear ratio is 13, and the dotted line at the top of the image is the curve of the yaw rate changing with time when the additional yaw torque is applied on the basis of the original vehicle with the virtual steering gear ratio determined as 13 according to the method for determining the yaw moment of the present invention.

[0085] The present invention can provide users with a stepless and adjustable steering style experience without changing the actual steering transmission ratio of the existing steering system by means of a virtual steering transmission ratio. By using the relationship between the additional yaw moment and the virtual steering transmission ratio provided by the present invention, the required additional yaw moment value can be directly calculated according to the virtual steering transmission ratio, which simplifies the calculation process and enables the effect of the additional yaw moment to be associated with the steering style of the whole vehicle through the steering transmission ratio. By adaptively calculating and correcting the virtual steering transmission ratio, the compatibility of the steering control system with different scenarios can be improved, and the maneuverability and stability of the vehicle can be improved.

[0086] It should be understood that the order of execution of the steps in the above embodiment does not necessarily 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 embodiment of the present invention.

[0087] In one embodiment, a device for determining a yaw moment is provided, such as Figure 8 As shown, the device 800 includes an acquisition module 801 and a determination module 802 .

[0088] An acquisition module 801 is used to acquire a steering wheel angle of a vehicle and a virtual steering gear ratio required by the vehicle in a target steering mode; The determination module 802 is used to determine the additional yaw moment corresponding to the virtual steering gear ratio and the steering wheel angle by using a preset conversion relationship; and use the additional yaw moment as the yaw moment compensated when the vehicle responds to the steering wheel angle to implement steering in the target steering mode; the preset conversion relationship includes the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment.

[0089] In one embodiment, the target steering mode includes an adaptive mode, and the acquisition module is used to: Get vehicle status; According to the vehicle state, the actual steering gear ratio of the vehicle is adaptively adjusted to determine the virtual steering gear ratio required by the vehicle in the adaptive mode.

[0090] In one embodiment, the target steering mode includes a custom mode, and the acquisition module is used to: Obtain the steering sensitivity selected by the user in the custom mode; The virtual steering transmission ratio corresponding to the steering sensitivity is used as the virtual steering transmission ratio required by the vehicle in the custom mode.

[0091] In one embodiment, the target steering mode includes a custom mode, and the acquisition module is used to: Obtain the steering sensitivity selected by the user in the custom mode; Get vehicle status; According to the vehicle state, the virtual steering transmission ratio corresponding to the steering sensitivity is adaptively adjusted to determine the virtual steering transmission ratio required by the vehicle in the custom mode.

[0092] In one embodiment, a preset state quantity is used to characterize the vehicle state; The preset state quantity includes at least one of the following: vehicle speed, yaw angular velocity, lateral acceleration, and maximum adhesion coefficient.

[0093] In one embodiment, the determining module is further used to: The determined additional yaw moment is corrected by using a pre-calibrated additional yaw moment implementation error to obtain a final additional yaw moment, wherein the additional yaw moment implementation error is a difference between a theoretical value and a measured value of the additional yaw moment.

[0094] In one embodiment, the device is further configured to determine the numerical relationship in the following manner: Determine an equation between a wheel angle change and an additional yaw moment simulation applied to the vehicle model, wherein the wheel angle change is a wheel angle change of a wheel corresponding to the steering wheel before and after the additional yaw moment simulation is applied when the vehicle model reaches a fixed yaw angular velocity; The virtual steering gear ratio is characterized by the ratio between the target steering angle and the steering wheel angle, so as to extract the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment simulation from the equation, wherein the target steering angle is the steering angle of the wheel corresponding to the steering wheel before the additional yaw moment simulation is applied. In summary, the device pre-constructs the numerical relationship between the virtual steering transmission ratio, the steering wheel angle, and the additional yaw moment, and uses the virtual steering transmission ratio to closely associate the steering wheel angle with the additional yaw moment, thereby introducing the steering wheel flexibility currently required by the vehicle into the determination of the yaw moment, that is, using the numerical relationship between the virtual steering transmission ratio, the steering wheel angle, and the additional yaw moment, the additional yaw moment that needs to be actively applied when the vehicle responds to a certain steering wheel angle in the target steering mode is determined. In this way, the actual yaw motion of the vehicle under the action of the additional yaw moment is matched with the steering wheel flexibility, thereby improving the maneuverability and stability of the entire vehicle. In one embodiment, an electronic device is provided, such as Fig. 9 As shown, the electronic device 900 includes a memory 901, a processor 902, and a computer program stored in the memory 901 and executable on the processor 902. When the processor 902 executes the computer program, the method for determining the yaw moment in any of the above embodiments is implemented. Alternatively, when the processor executes the computer program, the functions of each module / unit in the embodiment of the device for determining the yaw moment are implemented. To avoid repetition, they are not described here.

[0095] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the method for determining the yaw moment in any of the above embodiments is implemented. Alternatively, when the computer program is executed by a processor, the functions of each module / unit in the embodiment of the device for determining the yaw moment are implemented, and to avoid repetition, they are not described here.

[0096] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0097] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0098] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for determining a yaw moment, characterized in that: The method comprises: Obtaining a steering wheel angle of a vehicle, and obtaining a virtual steering transmission ratio required by the vehicle in a target steering mode; Determine the additional yaw moment corresponding to the virtual steering transmission ratio and the steering wheel angle by using a preset conversion relationship; using the additional yaw moment as a yaw moment compensated when the vehicle performs steering in response to the steering wheel angle in the target steering mode; The preset conversion relationship includes a numerical relationship between a virtual steering gear ratio, a steering wheel angle and an additional yaw moment.

2. The method according to claim 1, characterized in that The target steering mode includes an adaptive mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Get vehicle status; According to the vehicle state, the actual steering gear ratio of the vehicle is adaptively adjusted to determine the virtual steering gear ratio required by the vehicle in the adaptive mode.

3. The method according to claim 1, characterized in that The target steering mode includes a custom mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Obtain the steering sensitivity selected by the user in the custom mode; The virtual steering transmission ratio corresponding to the steering sensitivity is used as the virtual steering transmission ratio required by the vehicle in the custom mode.

4. The method according to claim 1, characterized in that The target steering mode includes a custom mode, and obtaining a virtual steering transmission ratio required by the vehicle in the target steering mode includes: Obtain the steering sensitivity selected by the user in the custom mode; Get vehicle status; According to the vehicle state, the virtual steering transmission ratio corresponding to the steering sensitivity is adaptively adjusted to determine the virtual steering transmission ratio required by the vehicle in the custom mode.

5. The method according to claim 2 or 4, characterized in that Using a preset state quantity to characterize the vehicle state; The preset state quantity includes at least one of the following: vehicle speed, yaw angular velocity, lateral acceleration, and maximum adhesion coefficient.

6. The method according to any one of claims 1 to 4, characterized in that: After determining the additional yaw moment corresponding to the virtual steering transmission ratio and the steering wheel angle by using the preset conversion relationship, the method further includes: The determined additional yaw moment is corrected by using a pre-calibrated additional yaw moment implementation error to obtain a final additional yaw moment, wherein the additional yaw moment implementation error is a difference between a theoretical value and a measured value of the additional yaw moment.

7. The method according to any one of claims 1 to 4, characterized in that: The numerical relationship is determined by: Determine an equation between a wheel angle change and an additional yaw moment simulation applied to the vehicle model, wherein the wheel angle change is a wheel angle change of a wheel corresponding to the steering wheel before and after the additional yaw moment simulation is applied when the vehicle model reaches a fixed yaw angular velocity; The virtual steering gear ratio is characterized by the ratio between the target steering angle and the steering wheel angle, so as to extract the numerical relationship between the virtual steering gear ratio, the steering wheel angle and the additional yaw moment simulation from the equation, wherein the target steering angle is the steering angle of the wheel corresponding to the steering wheel before the additional yaw moment simulation is applied.

8. A device for determining a yaw moment, characterized in that: The device comprises: An acquisition module, used for acquiring a steering wheel angle of a vehicle and acquiring a virtual steering transmission ratio required by the vehicle in a target steering mode; A determination module, configured to determine an additional yaw moment corresponding to the virtual steering transmission ratio and the steering wheel angle by using a preset conversion relationship; using the additional yaw moment as a yaw moment compensated when the vehicle performs steering in response to the steering wheel angle in the target steering mode; The preset conversion relationship includes a numerical relationship between a virtual steering gear ratio, a steering wheel angle and an additional yaw moment.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for determining the yaw moment according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for determining the yaw moment according to any one of claims 1 to 7 is implemented.

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