Method for determining adhesion coefficient, device, vehicle, medium, and program product

Abstract

The present disclosure provides a method, apparatus, vehicle, medium, and program product for determining an adhesion coefficient. The method comprises the steps of: obtaining tire information for each tire of a vehicle—tire information including the tire longitudinal force, tire lateral force, and tire vertical load of the tire—; determining a first adhesion coefficient of the vehicle based on the tire information of each tire; determining a gain coefficient based on the first adhesion coefficient and the tire information of each tire; determining a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle; and determining a target adhesion coefficient of the vehicle based on the first adhesion coefficient and the second adhesion coefficient. The method of the embodiments of the present application improves the accuracy of determining the target adhesion coefficient of the vehicle, thereby ensuring that the target adhesion coefficient of the vehicle matches actual conditions, thereby improving the anti-slip control performance of the vehicle and enhancing the safety of the occupants.

Description

Technology Field

[0001] The embodiments of the present application relate to the field of vehicle technology, and in particular to a method for determining an attachment coefficient, an apparatus, a vehicle, a medium, and a program product.

[0002] The present application claims priority to a Chinese patent application filed with the Chinese Patent Office on March 15, 2024, with application number 202410301423.0 and titled “Method, apparatus, vehicle, medium and program product for determining attachment coefficient,” the entire contents of which are incorporated by reference into the present application. Background Technology

[0003] The vehicle's adhesion coefficient plays an important role in the vehicle's performance of longitudinal drive anti-slip control. The problem to be solved

[0004] The following is an overview of the subject matter described in detail in this specification. This overview is not intended to limit the scope of protection of the claims.

[0005] Embodiments of the present application provide a method, apparatus, vehicle, medium, and program product for determining an adhesion coefficient. By increasing the accuracy of determining the adhesion coefficient and improving the degree of agreement between the adhesion coefficient and the actual conditions of the vehicle, the anti-slip control performance of the vehicle is improved, and the safety of the occupants is enhanced. means of solving the problem

[0006] In a first aspect, an embodiment of the present application provides a method for determining an adhesion coefficient, said method for determining an adhesion coefficient is applied to a vehicle, said method, said method,

[0007] Step of acquiring tire information for each tire of a vehicle - tire information includes the tire longitudinal force, tire lateral force, and tire vertical load - ;

[0008] A step of determining a first adhesion coefficient of a vehicle based on tire information of each tire;

[0009] A step of determining a gain coefficient based on a first adhesion coefficient and tire information of each tire;

[0010] A step of determining a second attachment coefficient based on a gain coefficient and the acceleration of the vehicle; and

[0011] It includes the step of determining a target attachment coefficient of a vehicle based on a first attachment coefficient and a second attachment coefficient.

[0012] In one implementation form, the step of determining a first adhesion coefficient of a vehicle based on tire information of each tire is,

[0013] For any one tire, a step of determining the adhesion coefficient of the tire based on the tire information of the tire; and

[0014] It includes the step of determining a first adhesion coefficient based on the adhesion coefficient of each tire.

[0015] In one embodiment, the step of determining a first adhesion coefficient based on the adhesion coefficient of each tire is,

[0016] A step to determine whether the vehicle has activated the stability control system;

[0017] When activated, a step of calculating a first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force and the tire lateral force corresponding to each tire; and

[0018] If not activated, the method includes the step of determining the turning state of the vehicle and determining a first adhesion coefficient based on the turning state and the adhesion coefficient of each tire.

[0019] In one embodiment, the step of calculating a first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force and the tire lateral force corresponding to each tire, is:

[0020] A step of determining the sum of the adhesion coefficients of each tire as the total adhesion coefficient;

[0021] A step of determining a target force in the horizontal plane of the vehicle based on the tire longitudinal force and tire lateral force corresponding to each tire; and

[0022] It includes the step of determining the ratio of the total adhesion coefficient to the target force as the first adhesion coefficient.

[0023] In one embodiment, the step of determining a first adhesion coefficient based on the turning state and the adhesion coefficient of each tire is,

[0024] When the turning state is a left turn state, a step of determining the maximum value among the attachment coefficient of the right front tire and the attachment coefficient of the right rear tire as the first attachment coefficient; and

[0025] When the turning state is a right turn or a straight state, the step of determining the maximum value among the attachment coefficient of the left front tire and the attachment coefficient of the left rear tire as the first attachment coefficient is included.

[0026] In one implementation form, the step of determining a gain coefficient based on a first adhesion coefficient and tire information of each tire is,

[0027] A step of determining the total tire attachment coefficient of the vehicle based on the tire information of each tire;

[0028] Step of determining the third attachment coefficient by multiplying the first attachment coefficient and a preset quantity - the preset quantity is the number of tires included in the vehicle - ; and

[0029] It includes a step of determining the ratio of the third adhesion coefficient to the total tire adhesion coefficient as the gain coefficient.

[0030] In one embodiment, acceleration includes longitudinal acceleration, lateral acceleration and gravitational acceleration; and the step of determining a second attachment coefficient based on a gain coefficient and the acceleration of the vehicle,

[0031] A step of determining a fourth attachment coefficient based on longitudinal acceleration, lateral acceleration and gravitational acceleration; and

[0032] It includes the step of determining the product of the gain coefficient and the fourth attachment coefficient as the second attachment coefficient.

[0033] In one embodiment, the step of determining the target attachment coefficient of the vehicle based on the first attachment coefficient and the second attachment coefficient is,

[0034] A step of determining a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on vehicle information and / or a second attachment coefficient of a vehicle - the vehicle information includes at least one of actual yaw angle, tire slip ratio, and longitudinal vehicle speed - ; and

[0035] It includes the step of determining a target attachment coefficient based on a first attachment coefficient, a second attachment coefficient, a first weight, and a second weight.

[0036] In a second aspect, an embodiment of the present application provides an apparatus for determining an adhesion coefficient, and said apparatus for determining an adhesion coefficient,

[0037] Acquisition module for acquiring tire information for each tire of a vehicle - tire information includes tire longitudinal force, tire lateral force, and tire vertical load - ;

[0038] It includes a processing module that determines a first adhesion coefficient of a vehicle based on tire information of each tire;

[0039] The processing module is also intended to determine a gain coefficient based on the first attachment coefficient and tire information of each tire;

[0040] The processing module is also intended to determine a second attachment coefficient based on the gain coefficient and the acceleration of the vehicle;

[0041] The processing module is also intended to determine the target attachment coefficient of the vehicle based on the first attachment coefficient and the second attachment coefficient.

[0042] In one implementation form, the processing module specifically,

[0043] For any single tire, determine the tire adhesion coefficient based on the tire information;

[0044] The first adhesion coefficient is determined based on the adhesion coefficient of each tire.

[0045] In one implementation form, the processing module specifically,

[0046] Determine whether the vehicle has activated the stability control system;

[0047] When activated, a first adhesion coefficient is calculated based on the adhesion coefficient of each tire, the tire longitudinal force and the tire lateral force corresponding to each tire;

[0048] If not activated, the turning state of the vehicle is determined, and the first adhesion coefficient is determined based on the turning state and the adhesion coefficient of each tire.

[0049] In one implementation form, the processing module specifically,

[0050] Determine the sum of the adhesion coefficients of each tire as the total adhesion coefficient;

[0051] Determining the target force in the horizontal plane of the vehicle based on the tire longitudinal force and tire lateral force corresponding to each tire;

[0052] The ratio of the total adhesion coefficient to the target force is determined as the first adhesion coefficient.

[0053] In one implementation form, the processing module specifically,

[0054] When the turning state is a left turn state, the maximum value among the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire is determined as the first adhesion coefficient;

[0055] When the turning state is a right turn or a straight state, the maximum value between the adhesion coefficient of the left front tire and the adhesion coefficient of the left rear tire is determined as the first adhesion coefficient.

[0056] In one implementation form, the processing module specifically,

[0057] Determine the total tire attachment coefficient of the vehicle based on the tire information of each tire;

[0058] The product of the first attachment coefficient and a preset quantity is determined as the third attachment coefficient, and the preset quantity is the number of tires included in the vehicle;

[0059] The ratio of the third adhesion coefficient to the total tire adhesion coefficient is determined as the gain coefficient.

[0060] In one implementation, acceleration includes longitudinal acceleration, lateral acceleration, and gravitational acceleration; and the processing module specifically,

[0061] A fourth attachment coefficient is determined based on longitudinal acceleration, lateral acceleration, and gravitational acceleration;

[0062] The product of the gain coefficient and the fourth attachment coefficient is determined as the second attachment coefficient.

[0063] In one implementation form, the processing module specifically,

[0064] Determining a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on vehicle information and / or a second attachment coefficient, wherein the vehicle information includes at least one of an actual yaw angle, a tire slip ratio, and a longitudinal vehicle speed;

[0065] The target attachment coefficient is determined based on the first attachment coefficient, the second attachment coefficient, the first weight, and the second weight.

[0066] In a third aspect, an embodiment of the present application provides a vehicle, and said vehicle,

[0067] Includes a processor and memory connected to communicate with the processor;

[0068] Memory is configured to store computer execution instructions;

[0069] The processor is configured to execute computer execution instructions stored in memory to implement the method for determining the attachment coefficient of the first embodiment.

[0070] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein a computer-readable storage medium stores a computer execution instruction, and the computer execution instruction is configured to implement the method for determining an attachment coefficient of the first aspect when executed by a processor.

[0071] In a fifth aspect, an embodiment of the present application provides a computer program product, the computer program product includes a computer program, and the computer program implements the method for determining an attachment coefficient of the first aspect when executed by a processor. Effects of the invention

[0072] Embodiments of the present application provide a method, apparatus, vehicle, medium, and program product for determining an adhesion coefficient. In the method, the vehicle acquires tire information for each tire of the vehicle, and the tire information includes the tire longitudinal force, tire lateral force, and tire vertical load of the tire. The vehicle determines a first adhesion coefficient of the vehicle based on the tire information of each tire. The vehicle determines a gain coefficient based on the first adhesion coefficient and the tire information of each tire, and determines a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle. The vehicle determines a target adhesion coefficient of the vehicle based on the first adhesion coefficient and the second adhesion coefficient. The method of the embodiment of the present application improves the accuracy of determining the adhesion coefficient and enhances the degree of agreement between the adhesion coefficient and the actual conditions of the vehicle, thereby improving the anti-slip control performance of the vehicle and enhancing the safety of the occupants.

[0073] After reading the attached drawings and detailed description, other embodiments can be understood. Brief explanation of the drawing

[0074] In the description below, the drawings are some embodiments of the present application, and it is obvious to those skilled in the art that other drawings can be obtained based on these drawings without creative effort. FIG. 1 is a schematic diagram of an application scenario to which an embodiment of the present application is applied. FIG. 2 is a flowchart of Example 1 of the method for determining the adhesion coefficient provided in the embodiment of the present application. FIG. 3 is a flowchart of Example 2 of the method for determining the adhesion coefficient provided in the embodiment of the present application. FIG. 4 is a flowchart of Example 3 of the method for determining the adhesion coefficient provided in the embodiment of the present application. FIG. 5 is a schematic diagram of the structure of an attachment coefficient determination device provided in an embodiment of the present application. FIG. 6 is a structural diagram of a vehicle provided in an embodiment of the present application. Specific details for implementing the invention

[0075] The described embodiments are only some of the embodiments of this application, not all of them. All other embodiments derived by a person skilled in the art based on the embodiments of this application and in accordance with the examples are all within the scope of protection of this application.

[0076] In the specification, claims, and drawings of this application, terms “first,” “second,” “third,” “fourth,” etc. (if present) are not used to describe a specific order or sequence, but are used to distinguish similar objects. It should be understood that the data used in this application may be compatible where appropriate, so that the embodiments of this application described herein may be practiced in an order other than that shown or described herein. Furthermore, the terms “include” and “have” and any variations are intended to encompass non-exclusive inclusions, and, for example, a process, method, system, product, or apparatus comprising a series of steps or units is not limited to the steps or units explicitly listed, but may include other steps or units not explicitly listed or unique to such process, method, product, or apparatus.

[0077] The vehicle's adhesion coefficient plays a crucial role in the vehicle's performance of longitudinal drive anti-slip control. In related technologies, the vehicle generally directly estimates the adhesion coefficient based on the ratio of longitudinal driving force to vertical load, and performs anti-slip control on the vehicle based on the estimated adhesion coefficient.

[0078] However, the method of directly estimating the adhesion coefficient based on the ratio of longitudinal driving force to vertical load may result in discrepancies between the estimated adhesion coefficient and the actual vehicle conditions; consequently, this leads to inaccurate anti-slip control of the vehicle, which can affect the safety of the occupants.

[0079] Taking these points into consideration, an embodiment of the present application provides a method for determining an adhesion coefficient, wherein the method determines a first adhesion coefficient of a vehicle based on tire information of each tire (tire longitudinal force, tire lateral force, and tire vertical load), determines a gain coefficient based on the first adhesion coefficient and the tire information of each tire, and can determine a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle. After determining the first adhesion coefficient and the second adhesion coefficient, the vehicle determines a target adhesion coefficient of the vehicle by fusing the first adhesion coefficient and the second adhesion coefficient. Through the above method, the accuracy of determining the adhesion coefficient can be increased, thereby improving the degree of correspondence between the adhesion coefficient and the actual conditions of the vehicle, and thereby improving the anti-slip control performance of the vehicle.

[0080] The principles and features of the embodiments of the present application are described below with reference to the attached drawings. The described embodiments are intended only to explain the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

[0081] FIG. 1 is a schematic diagram of an application scenario to which an embodiment of the present application is applied. The application scenario includes a vehicle (10), and the vehicle (10) includes a plurality of tires. For example, FIG. 1 illustrates four tires, each being a left front tire (101), a right front tire (102), a left rear tire (103), and a right rear tire (104).

[0082] An example is given in which the vehicle (10) includes a left front tire (101), a right front tire (102), a left rear tire (103), and a right rear tire (104).

[0083] The vehicle (10) obtains tire information of the left front tire (101), tire information of the right front tire (102), tire information of the left rear tire (103), and tire information of the right rear tire (104). Here, the tire information includes the tire longitudinal force, tire lateral force, and tire vertical load.

[0084] The vehicle (10) determines a first attachment coefficient of the vehicle (10) based on tire information of the left front tire (101), tire information of the right front tire (102), tire information of the left rear tire (103), and tire information of the right rear tire (104).

[0085] The vehicle (10) determines a gain coefficient based on the first attachment coefficient, tire information of the left front tire (101), tire information of the right front tire (102), tire information of the left rear tire (103), and tire information of the right rear tire (104).

[0086] The vehicle (10) determines a second attachment coefficient based on the gain coefficient and the acceleration of the vehicle.

[0087] The vehicle (10) determines the target attachment coefficient of the vehicle (10) based on the first attachment coefficient and the second attachment coefficient.

[0088] The technical solution of the present application is described in detail below through specific embodiments. The following specific embodiments may be combined with one another, and identical or similar concepts or processes may be omitted from repeated descriptions in some embodiments.

[0089] FIG. 2 is a flowchart of Example 1 of the method for determining an adhesion coefficient provided in an embodiment of the present application. Referring to FIG. 2, the method specifically comprises the following steps:

[0090] Step (S201): Obtain tire information for each tire of the vehicle.

[0091] In this embodiment, the vehicle can acquire tire information for each tire of the vehicle, and the tire information includes the tire longitudinal force, tire lateral force, and tire vertical load.

[0092] Step (S202): Determine the first adhesion coefficient of the vehicle based on the tire information of each tire.

[0093] In this embodiment, the vehicle can determine the first adhesion coefficient of the vehicle based on the tire information of each tire.

[0094] Specifically, for any one tire, the vehicle can determine the adhesion coefficient of the tire based on the tire information of the tire.

[0095] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). The vehicle can determine the adhesion coefficient of the corresponding tire based on the tire information based on the formula below.

[0096]

[0097] Here, MueUtilWhl(k) represents the tire adhesion coefficient. Fx_N(k) represents the tire longitudinal force, Fy_N(k) represents the tire lateral force, and Fz_N(k) represents the tire vertical load. k=1 represents the left front tire, k=2 represents the right front tire, k=3 represents the left rear tire, and k=4 represents the right rear tire.

[0098] After calculating the adhesion coefficient of each vehicle, the vehicle can determine the first adhesion coefficient based on the adhesion coefficient of each tire.

[0099] Step (S203): Determine the gain coefficient based on the first adhesion coefficient and the tire information of each tire.

[0100] In this embodiment, the vehicle can determine a gain coefficient based on a first attachment coefficient and tire information of each tire.

[0101] Specifically, the vehicle can determine the total tire adhesion coefficient of the vehicle based on the tire information of each tire (tire longitudinal force, tire lateral force, and tire vertical load).

[0102] The vehicle can determine the third attachment coefficient by multiplying the first attachment coefficient by a preset quantity. Here, the preset quantity is the number of tires included in the vehicle.

[0103] The vehicle determines the ratio of the third adhesion coefficient to the total tire adhesion coefficient as the gain coefficient.

[0104] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). The vehicle can determine a gain coefficient based on the first attachment coefficient and tire information of each tire based on the formula below.

[0105]

[0106] Here, Gain represents the gain factor. Fx_N(k) represents the tire longitudinal force, Fy_N(k) represents the tire lateral force, and Fz_N(k) represents the tire vertical load. k=1 represents the left front tire, k=2 represents the right front tire, k=3 represents the left rear tire, and k=4 represents the right rear tire. MueUtilFromTqMdl represents the first adhesion factor.

[0107] Step (S204): Determine the second attachment coefficient based on the gain coefficient and the acceleration of the vehicle.

[0108] In this embodiment, the vehicle can determine a second attachment coefficient based on a gain coefficient and the acceleration of the vehicle. Here, the acceleration includes longitudinal acceleration, lateral acceleration, and gravitational acceleration.

[0109] Specifically, the vehicle can determine a fourth attachment coefficient based on longitudinal acceleration, lateral acceleration, and gravitational acceleration. The vehicle can determine the product of the gain coefficient and the fourth attachment coefficient as the second attachment coefficient.

[0110] The vehicle can determine the second attachment coefficient based on the formula below.

[0111]

[0112] Here, MueUtilWhlIMU represents the second adhesion coefficient.

[0113] Gain represents the gain coefficient.

[0114] a x represents longitudinal acceleration, and a y represents lateral acceleration. a x and a y It should be noted that this is detected by an inertial measurement unit (IMU) motion sensor.

[0115] represents the fourth adhesion coefficient.

[0116] Step (S205): Determine the target attachment coefficient of the vehicle based on the first attachment coefficient and the second attachment coefficient.

[0117] In this embodiment, after determining a first attachment coefficient and a second attachment coefficient, the vehicle can determine a target coefficient of the vehicle based on the first attachment coefficient and the second attachment coefficient.

[0118] In one implementation, the vehicle may determine the vehicle's target coefficient as the sum of the product of a first attachment coefficient and a preset first weight and the product of a second attachment coefficient and a preset second weight.

[0119] In one embodiment, the vehicle may determine a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on the acquired vehicle information and / or a second attachment coefficient. The vehicle may determine a target attachment coefficient based on the first attachment coefficient, the second attachment coefficient, the first weight, and the second weight.

[0120] Beneficial effects of the present embodiment: In the present embodiment, the vehicle determines a first adhesion coefficient based on tire information (tire longitudinal force, tire lateral force, and tire vertical load) of each tire, determines a gain coefficient based on the first adhesion coefficient and the tire information of each tire, and can determine a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle. After determining the first adhesion coefficient and the second adhesion coefficient, the vehicle determines a target adhesion coefficient of the vehicle by fusing the first adhesion coefficient and the second adhesion coefficient. Through the above method, the accuracy of determining the adhesion coefficient can be increased, thereby improving the degree of correspondence between the adhesion coefficient and the actual situation of the vehicle, and thereby improving the anti-slip control performance of the vehicle.

[0121] Hereinafter, the process of determining the first adhesion coefficient of the vehicle based on the tire information of each tire through Method Example 2 is described in detail.

[0122] FIG. 3 is a flowchart of Example 2 of the method for determining an adhesion coefficient provided in an embodiment of the present application. Referring to FIG. 3, the method specifically comprises the following steps:

[0123] Step (S301): For any one tire, the adhesion coefficient of the tire is determined based on the tire information of the tire.

[0124] In this embodiment, for any one tire, the vehicle can determine the adhesion coefficient of the tire based on the tire information of the tire.

[0125] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). The vehicle can determine the adhesion coefficient of the corresponding tire based on the tire information according to the formula below.

[0126]

[0127] Here, MueUtilWhl(k) represents the tire adhesion coefficient. Fx_N(k) represents the tire longitudinal force, Fy_N(k) represents the tire lateral force, and Fz_N(k) represents the tire vertical load. k=1 represents the left front tire, k=2 represents the right front tire, k=3 represents the left rear tire, and k=4 represents the right rear tire.

[0128] Step (S302): Determines whether the vehicle has activated the stability control system.

[0129] In this embodiment, the vehicle can determine whether the vehicle has activated the stability control system.

[0130] If activated, execute step (S303);

[0131] If not activated, execute step (S304).

[0132] In one implementation, the vehicle determines that the stability control system is activated when the braking flag of one tire (wheel) is set and the braking torque of the tire (wheel) is recognized to be greater than 0.

[0133] In one implementation, the vehicle determines that the stability control system is activated when the control flag of the anti-lock braking system (ABS) of one tire (wheel) is set and the braking torque of the tire (wheel) is recognized as being greater than 0.

[0134] In one implementation, the vehicle determines that the stability control system is activated when one tire (wheel) corresponds to the identifier of the tire (wheel) during the lifting torque request, and the slip ratio of the tire (wheel) is recognized as being greater than 0.

[0135] Step (S303): Calculate the first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force and the tire lateral force corresponding to each tire.

[0136] In this embodiment, when it is determined that the vehicle has activated the stability control system, the vehicle calculates a first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force corresponding to each tire, and the tire lateral force.

[0137] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). The vehicle can calculate a first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force and tire lateral force corresponding to each tire, based on the formula below.

[0138]

[0139] Here, MueUtilFromTqMdl represents the first attachment coefficient.

[0140] Fx_N(k) represents the tire longitudinal force, Fy_N(k) represents the tire lateral force, and Fz_N(k) represents the tire vertical load.

[0141] k=1 represents the left front tire, k=2 represents the right front tire, k=3 represents the left rear tire, and k=4 represents the right rear tire.

[0142] represents the adhesion coefficient of a single tire.

[0143] Step (S304): Determine the turning state of the vehicle, and determine the first adhesion coefficient based on the turning state and the adhesion coefficient of each tire.

[0144] In this embodiment, the vehicle determines the turning state of the vehicle when it is determined that the vehicle has not activated the stability control system. Here, the turning state includes a left-turn state, a right-turn state, and a straight state.

[0145] The vehicle can determine a first adhesion coefficient based on the turning state and the adhesion coefficient of each tire.

[0146] Specifically, when the turning state is a left turn, the maximum value between the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire is determined as the first adhesion coefficient.

[0147] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). Based on the formula below, the vehicle can determine the maximum value between the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire as the first adhesion coefficient.

[0148]

[0149] Here, MueUtilFromTqMdl represents the first adhesion coefficient. MueUtilWhl (2) represents the adhesion coefficient of the right front tire. MueUtilWhl (4) represents the adhesion coefficient of the right rear tire.

[0150] When the turning state is a right turn or a straight state, the maximum value between the adhesion coefficient of the left front tire and the adhesion coefficient of the left rear tire is determined as the first adhesion coefficient.

[0151] For example, let us consider a case where a vehicle has four tires (left front tire, right front tire, left rear tire, and right rear tire). Based on the formula below, the vehicle can determine the maximum value between the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire as the first adhesion coefficient.

[0152]

[0153] Here, MueUtilFromTqMdl represents the first adhesion coefficient. MueUtilWhl (1) represents the adhesion coefficient of the left front tire. MueUtilWhl (3) represents the adhesion coefficient of the left rear tire.

[0154] Beneficial effects of the present embodiment: In the present embodiment, when it is determined that the vehicle has activated the stability control system, the vehicle can calculate a first adhesion coefficient based on the adhesion coefficient of each tire, the tire longitudinal force corresponding to each tire, and the tire lateral force. When it is determined that the vehicle has not activated the stability control system, the vehicle can determine the turning state of the vehicle and determine the first adhesion coefficient based on the turning state and the adhesion coefficient of each tire. By recognizing whether the vehicle has activated the stability control system as described above, the first adhesion coefficient is determined in an appropriate manner, thereby improving the accuracy of determining the first adhesion coefficient, and thereby improving the accuracy of determining the target adhesion coefficient of the vehicle based on the first adhesion coefficient.

[0155] Hereinafter, the process of determining the target attachment coefficient of a vehicle based on the first attachment coefficient and the second attachment coefficient through Method Example 3 is described in detail.

[0156] FIG. 4 is a flowchart of Example 3 of the method for determining the adhesion coefficient provided in an embodiment of the present application. Referring to FIG. 4, the method specifically comprises the following steps:

[0157] Step (S401): Based on the vehicle information of the vehicle and / or the second attachment coefficient, the first weight of the first attachment coefficient and the second weight of the second attachment coefficient are determined.

[0158] In this embodiment, the vehicle may determine a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on vehicle information and / or a second attachment coefficient. Here, the vehicle information includes at least one of an actual yaw angle, a tire slip ratio, and a longitudinal vehicle speed.

[0159] For example, a case is given in which a vehicle determines a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on the actual yaw angle, tire slip ratio, longitudinal vehicle speed, and a second attachment coefficient.

[0160] The vehicle can determine the error between the actual yaw angle and the reference value based on the actual yaw angle, and determine the first correction weighting coefficient by querying a table stored in the vehicle based on the error between the actual yaw angle and the reference value.

[0161] The vehicle can determine the variance of the rate of change of the tire slip ratio based on the tire slip ratio, and determine a second correction weighting coefficient by querying a table stored in the vehicle based on the variance of the rate of change of the tire slip ratio.

[0162] The vehicle can determine the third correction weighting coefficient by querying a table stored in the vehicle based on the second attachment coefficient.

[0163] The vehicle can determine the fourth correction weighting coefficient by querying a table stored in the vehicle based on the longitudinal vehicle speed.

[0164] The vehicle can determine the first weight based on the first correction weight coefficient, the second correction weight coefficient, the third correction weight coefficient, and the fourth correction weight coefficient based on the formula below.

[0165]

[0166] Here, λ1 represents the first weight. Factor1 represents the first correction weight coefficient. Factor2 represents the second correction weight coefficient. Factor3 represents the third correction weight coefficient. Factor4 represents the fourth correction weight coefficient.

[0167] After determining the first weight, the vehicle can determine the second weight based on the formula below.

[0168]

[0169] Here, λ1 represents the first weight. λ2 represents the first weight.

[0170] Step (S402): Determine the target attachment coefficient based on the first attachment coefficient, the second attachment coefficient, the first weight, and the second weight.

[0171] In this embodiment, the vehicle can determine a target attachment coefficient based on a first attachment coefficient, a second attachment coefficient, a first weight, and a second weight.

[0172] Specifically, the vehicle can determine the target attachment coefficient based on the following formula.

[0173]

[0174] Here, λ1 represents the first weight. λ2 represents the first weight. MueUtilFromTqMdl represents the first attachment coefficient. MueUtilWhlIMU represents the second attachment coefficient.

[0175] Beneficial effects of the present embodiment: The vehicle determines a first weight and a second weight based on vehicle information and / or a second attachment coefficient, and furthermore, can appropriately fuse the first attachment coefficient and the second attachment coefficient based on the first weight and the second weight, thereby increasing the accuracy of determining the target attachment coefficient of the vehicle and improving the degree of agreement between the target attachment coefficient and the actual vehicle situation, and thereby improving the control effect of the vehicle.

[0176] The following is an apparatus embodiment of the present application and may be used to implement a method embodiment of the present application. For details not disclosed in the apparatus embodiment of the present application, refer to the method embodiment of the present application.

[0177] FIG. 5 is a schematic diagram of the structure of an attachment coefficient determination device provided in an embodiment of the present application. As shown in FIG. 5, the attachment coefficient determination device (50) includes an acquisition module (51) and a processing module (52).

[0178] Here, the acquisition module (51) acquires tire information for each tire of the vehicle, and the tire information includes the tire longitudinal force, tire lateral force, and tire vertical load of the tire;

[0179] The processing module (52) determines the first attachment coefficient of the vehicle based on the tire information of each tire;

[0180] The processing module (52) also determines a gain coefficient based on the first attachment coefficient and tire information of each tire;

[0181] The processing module (52) also determines a second attachment coefficient based on the gain coefficient and the acceleration of the vehicle;

[0182] The processing module (52) also determines the target attachment coefficient of the vehicle based on the first attachment coefficient and the second attachment coefficient.

[0183] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0184] In one implementation form, the processing module (52) specifically,

[0185] For any single tire, determine the tire adhesion coefficient based on the tire information;

[0186] The first adhesion coefficient is determined based on the adhesion coefficient of each tire.

[0187] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution shown in the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0188] In one implementation form, the processing module (52) specifically,

[0189] Determine whether the vehicle has activated the stability control system;

[0190] When activated, a first adhesion coefficient is calculated based on the adhesion coefficient of each tire, the tire longitudinal force and the tire lateral force corresponding to each tire;

[0191] If not activated, the turning state of the vehicle is determined, and the first adhesion coefficient is determined based on the turning state and the adhesion coefficient of each tire.

[0192] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0193] In one implementation form, the processing module (52) specifically,

[0194] Determine the sum of the adhesion coefficients of each tire as the total adhesion coefficient;

[0195] Determining the target force in the horizontal plane of the vehicle based on the tire longitudinal force and tire lateral force corresponding to each tire;

[0196] The ratio of the total adhesion coefficient to the target force is determined as the first adhesion coefficient.

[0197] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0198] In one implementation form, the processing module (52) specifically,

[0199] When the turning state is a left turn state, the maximum value among the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire is determined as the first adhesion coefficient;

[0200] When the turning state is a right turn or a straight state, the maximum value between the adhesion coefficient of the left front tire and the adhesion coefficient of the left rear tire is determined as the first adhesion coefficient.

[0201] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0202] In one implementation form, the processing module (52) specifically,

[0203] Determine the total tire attachment coefficient of the vehicle based on the tire information of each tire;

[0204] The product of the first attachment coefficient and a preset quantity is determined as the third attachment coefficient, and the preset quantity is the number of tires included in the vehicle;

[0205] The ratio of the third adhesion coefficient to the total tire adhesion coefficient is determined as the gain coefficient.

[0206] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0207] In one embodiment, acceleration includes longitudinal acceleration, lateral acceleration and gravitational acceleration; and the processing module (52) specifically,

[0208] A fourth attachment coefficient is determined based on longitudinal acceleration, lateral acceleration, and gravitational acceleration;

[0209] The product of the gain coefficient and the fourth attachment coefficient is determined as the second attachment coefficient.

[0210] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0211] In one implementation form, the processing module (52) specifically,

[0212] Determining a first weight of a first attachment coefficient and a second weight of a second attachment coefficient based on vehicle information and / or a second attachment coefficient, wherein the vehicle information includes at least one of an actual yaw angle, a tire slip ratio, and a longitudinal vehicle speed;

[0213] The target attachment coefficient is determined based on the first attachment coefficient, the second attachment coefficient, the first weight, and the second weight.

[0214] The device for determining the attachment coefficient provided in the embodiment of the present application can implement the technical solution according to the method embodiment, and since the implementation principle and beneficial effects are similar, they are not described repeatedly here.

[0215] FIG. 6 is a structural diagram of a vehicle provided in an embodiment of the present application. As shown in FIG. 6, the vehicle (60) includes a processor (61) and a memory (62). Here, the processor (61) is connected to the memory (62) for communication, and the memory (62) is configured to store computer execution commands; the processor (61) is configured to execute the technical method of any one of the aforementioned method embodiments by executing the computer execution commands stored in the memory (62).

[0216] Optionally, the memory (62) may be independent or integrated with the processor (61). Optionally, if the memory (62) is a separate component from the processor (61), the vehicle (60) may also include a bus for connecting the components.

[0217] The above vehicle is intended to implement the technical plan of any one of the aforementioned method embodiments, and since its implementation principles and technical effects are similar, they are not described repeatedly here.

[0218] Embodiments of the present application also provide a computer-readable storage medium, wherein computer-readable storage medium stores computer execution instructions, and the computer execution instructions are configured to implement the technical solution provided in any one of the aforementioned method embodiments when executed by a processor.

[0219] Embodiments of the present application also provide a computer program product, said computer program product includes a computer program, and the computer program is configured to implement the technical solution provided in the aforementioned method embodiment when executed by a processor.

[0220] A person skilled in the art will understand that all or part of the steps of the above method may be completed by instructing the relevant hardware (processor) through a program. The aforementioned program may be stored on a computer-readable storage medium, for example, read-only memory, a magnetic disk, or an optical disk. Optionally, all or part of the steps of the above-described embodiment may be implemented using one or more integrated circuits. Correspondingly, each module / unit of the above-described embodiment may be implemented in the form of hardware, for example, by implementing its corresponding function through an integrated circuit, or it may be implemented in the form of a software function module, or it may be implemented by executing a program / instruction stored in memory through a processor, for example. The present application is not limited to any specific combination of hardware and software.

[0221] Finally, each of the above embodiments is used only to illustrate the technical solution of the present application and is not a limitation thereon; although the embodiments of the present application have been described in detail with reference to the aforementioned embodiments, a person skilled in the art may modify the technical solution described in each of the aforementioned embodiments or replace some or all of the technical features with equivalents; and it should be understood that such modification or replacement does not cause the essence of the technical solution to depart from the scope of the technical solution of each embodiment of the present application.

Claims

Claim 1 A method for determining an adhesion coefficient, applied to a vehicle, comprising: a step of obtaining tire information of each tire of the vehicle—the tire information including the tire longitudinal force, tire lateral force, and tire vertical load of the tire—; a step of determining a first adhesion coefficient of the vehicle based on the tire information of each tire; a step of determining a gain coefficient based on the first adhesion coefficient and the tire information of each tire; a step of determining a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle; and a step of determining a target adhesion coefficient of the vehicle based on the first adhesion coefficient and the second adhesion coefficient. Claim 2 A determination method according to claim 1, wherein for any one tire, the adhesion coefficient of the tire is determined based on the tire information of the tire; and the first adhesion coefficient is determined based on the adhesion coefficient of each tire. Claim 3 A method for determining, wherein, in paragraph 2, the vehicle determines whether the stability control system is activated; if activated, the first adhesion coefficient is calculated based on the adhesion coefficient of each tire, the tire longitudinal force corresponding to each tire, and the tire lateral force; and if not activated, the turning state of the vehicle is determined, and the first adhesion coefficient is determined based on the turning state and the adhesion coefficient of each tire. Claim 4 A method for determining, wherein, in paragraph 3, the sum of the adhesion coefficients of each tire is determined as the total adhesion coefficient; a target force in the horizontal plane of the vehicle is determined based on the tire longitudinal force and tire lateral force corresponding to each tire; and the ratio of the total adhesion coefficient to the target force is determined as the first adhesion coefficient. Claim 5 A method for determining, wherein, in the case of the turning state being a left turn state, the maximum value among the adhesion coefficient of the right front tire and the adhesion coefficient of the right rear tire is determined as the first adhesion coefficient; and in the case of the turning state being a right turn state or a straight state, the maximum value among the adhesion coefficient of the left front tire and the adhesion coefficient of the left rear tire is determined as the first adhesion coefficient. Claim 6 A method for determining, wherein in any one of claims 1 to 5, the total tire attachment coefficient of the vehicle is determined based on tire information of each tire; the product of the first attachment coefficient and a preset quantity is determined as the third attachment coefficient, wherein the preset quantity is the number of tires included in the vehicle; and the ratio of the third attachment coefficient to the total tire attachment coefficient is determined as the gain coefficient. Claim 7 A determination method according to any one of claims 1 to 6, wherein the acceleration includes longitudinal acceleration, lateral acceleration and gravitational acceleration; a fourth attachment coefficient is determined based on the longitudinal acceleration, the lateral acceleration and the gravitational acceleration; and the product of the gain coefficient and the fourth attachment coefficient is determined as the second attachment coefficient. Claim 8 A method for determining, wherein, in any one of claims 1 to 7, a first weight of the first attachment coefficient and a second weight of the second attachment coefficient are determined based on vehicle information of the vehicle and / or the second attachment coefficient, wherein the vehicle information includes at least one of actual yaw angle, tire slip rate and longitudinal vehicle speed; and a target attachment coefficient is determined based on the first attachment coefficient, the second attachment coefficient, the first weight and the second weight. Claim 9 A device for determining an adhesion coefficient, comprising: an acquisition module for acquiring tire information of each tire of a vehicle, wherein the tire information includes the tire longitudinal force, tire lateral force, and tire vertical load of the tire; a processing module for determining a first adhesion coefficient of the vehicle based on the tire information of each tire; wherein the processing module also determines a gain coefficient based on the first adhesion coefficient and the tire information of each tire; wherein the processing module also determines a second adhesion coefficient based on the gain coefficient and the acceleration of the vehicle; and wherein the processing module also determines a target adhesion coefficient of the vehicle based on the first adhesion coefficient and the second adhesion coefficient. Claim 10 A vehicle comprising a processor and a memory connected to communicate with said processor; said memory configured to store computer execution commands; and said processor configured to execute computer execution commands stored in said memory to implement a method for determining an attachment coefficient according to any one of claims 1 to 8. Claim 11 A computer-readable storage medium, wherein the computer-readable storage medium stores a computer execution command, and the computer execution command is configured to implement a method for determining an attachment coefficient according to any one of claims 1 to 8 when executed by a processor. Claim 12 A computer program product comprising a computer program, wherein the computer program implements a method for determining an attachment coefficient according to any one of claims 1 to 8 when executed by a processor.

Images