Integrated tire longitudinal and lateral force estimation method

Abstract

A method for estimating a lateral force includes receiving vehicle data. The vehicle includes a plurality of tires. The method further includes using the bicycle model to determine a first lateral force at each of the plurality of tires of the vehicle; using the dual track model to determine a second lateral force at each of the plurality of tires of the vehicle; fusing a first lateral force determined using the bicycle model with a second lateral force determined using the dual track model to determine a third lateral force at each of the plurality of tires of the vehicle; and controlling an actuator of the vehicle using the third lateral force at each of the plurality of tires of the vehicle.

Description

Technical Field

[0001] The present disclosure relates to methods and systems for integrated tire longitudinal and lateral force estimation. Background Art

[0002] This introduction generally presents the context of the present disclosure. To the extent described in this introduction, the work of the presently named inventors and aspects of the description that may not constitute prior art at the time of filing are neither expressly nor impliedly admitted to be prior art to the present disclosure.

[0003] Most motor vehicles include tires. These tires exert longitudinal and lateral forces that affect the vehicle dynamics. The control of some vehicle actuators may depend on the longitudinal and lateral forces of the tires. It is therefore desirable to estimate the longitudinal and lateral forces of the tires. The longitudinal tire forces are not considered when estimating the lateral tire forces. When the longitudinal tire forces differ significantly between the corners or each side of the vehicle (which may occur due to torque vectoring, road conditions, or lateral load transfer), the simplified bicycle model cannot accurately estimate the lateral tire forces. Summary of the invention

[0004] In order to accurately estimate the lateral tire forces, the present disclosure describes a more comprehensive lateral dynamics model to incorporate the effects of the longitudinal tire forces. The presently disclosed method uses multiple criteria to detect conditions when the longitudinal tire forces are inaccurate and when the external yaw moment is significant. A significant external yaw moment is one that is generated by the difference in longitudinal forces on each side / corner. The presently disclosed method also includes fusion logic that creates a smooth transition between the two methods (i.e., the simplified bicycle model and the dual-track integrated lateral force estimation model).

[0005] In one aspect of the present disclosure, a method for estimating lateral tire forces includes receiving data of a vehicle. The vehicle includes a plurality of tires. The method includes determining a first lateral force at each of the plurality of tires of the vehicle using a bicycle model; determining a second lateral force at each of the plurality of tires of the vehicle using a double-track model; and fusing the first lateral force determined using the bicycle model and the second lateral force determined using the double-track model to determine a third lateral force at each of the plurality of tires of the vehicle. The method also includes controlling an actuator of the vehicle using the third lateral force at each of the plurality of tires of the vehicle.

[0006] The vehicle data includes a plurality of wheel slips at each of a plurality of tires of the vehicle. In other aspects of the present disclosure, the method may further include determining a maximum wheel slip among the plurality of wheel slips at each of a plurality of tires of the vehicle; determining an absolute value of the maximum wheel slip; and comparing the absolute value of the maximum wheel slip with a predetermined wheel slip threshold to determine whether the absolute value of the maximum wheel slip is less than the predetermined wheel slip threshold. The vehicle data includes a vehicle speed. The method may further include comparing the vehicle speed of the vehicle with a predetermined speed threshold to determine whether the vehicle speed of the vehicle is greater than the predetermined speed threshold. The vehicle data includes a yaw moment generated by a longitudinal force at each of a plurality of tires of the vehicle. The method may further include comparing the yaw moment generated by a longitudinal force at each of a plurality of tires of the vehicle with a predetermined moment threshold to determine whether the yaw moment generated by a longitudinal force at each of a plurality of tires of the vehicle is greater than the predetermined moment threshold. A first lateral force at each of a plurality of tires of the vehicle and a second lateral force at each of a plurality of tires of the vehicle are determined only in response to determining that: (a) an absolute value of a maximum wheel slip is less than a wheel slip threshold, (b) a vehicle speed of the vehicle is greater than a predetermined speed threshold, and (c) a yaw moment generated by the longitudinal force at each of the plurality of tires of the vehicle is greater than a predetermined moment threshold. The second lateral force at each of the plurality of tires of the vehicle includes a concentrated lateral force in a front axle of the vehicle, and the dual track model uses the following, among others:

[0007]

[0008]

[0009] in:

[0010] F yf is the concentrated lateral force on the front axle of the vehicle;

[0011] m is the mass of the vehicle;

[0012] a y is the lateral acceleration of the vehicle;

[0013] is the yaw acceleration of the vehicle;

[0014] L r is the distance from the rear axle to the vehicle’s center of gravity;

[0015] I zz is the yaw moment of inertia of the vehicle;

[0016] is the yaw moment generated by the longitudinal tire force on the vehicle;

[0017] i refers to the left or right tire of the vehicle;

[0018] j refers to the front or rear axle of the vehicle;

[0019] is the tire longitudinal force at bridge j and tire i;

[0020] F xf is the concentrated longitudinal force on the front axle of the vehicle;

[0021] δ f is the front wheel steering angle on the road; and

[0022] L f is the distance from the front axle to the vehicle's center of gravity;

[0023] F yr is the concentrated lateral force in the rear axle of the vehicle;

[0024] F xr is the concentrated longitudinal force on the rear axle of the vehicle; and

[0025] δ r is the rear wheel steering angle on the road.

[0026] Fusing the first lateral force determined using the bicycle model and the second lateral force determined using the dual track model includes using a low pass filter having a first convergence rate for a falling edge, a second convergence rate for a rising edge, and the first convergence rate being different from the second convergence rate.

[0027] The present disclosure describes a system for estimating lateral force. The system includes a sensor, an actuator, and a controller in communication with the sensor and the actuator. The controller is programmed to perform the above method. The present disclosure also describes a vehicle, which includes a vehicle body, a sensor, an actuator, and a controller in communication with the sensor and the actuator. The controller is programmed to perform the above method.

[0028] Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter.It should be understood that the detailed description and specific examples are intended for illustration purposes only and are not intended to limit the scope of the present disclosure.

[0029] The above features and advantages of the systems and methods disclosed herein and other features and advantages are apparent from the detailed description of exemplary embodiments of the systems and methods disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present disclosure will be more fully understood based on the following detailed description and accompanying drawings, in which:

[0031] Figure 1is a schematic side view of a vehicle including a system for lateral force estimation; and

[0032] Figure 2 is a flow chart of a method for lateral force estimation. DETAILED DESCRIPTION

[0033] Reference will now be made in detail to several examples of the present disclosure, which are illustrated in the accompanying drawings. Whenever possible, the same or similar reference numerals are used in the drawings and the description to refer to the same or similar components or steps.

[0034] refer to Figure 1 , the vehicle 10 includes (or is in communication with) a control system 11. Although the system 11 is shown as being internal to the vehicle 10, it is contemplated that the system 11 may be external to the vehicle 10. As a non-limiting example, the system 11 may be in wireless communication with the vehicle 10. Although the vehicle 10 is shown as a coupe, it is contemplated that the vehicle 10 may be another type of vehicle, such as a light truck, a sedan, a sport utility vehicle (SUV), a recreational vehicle (RV), etc. The system 11 may be used to accurately estimate tire lateral forces.

[0035] In addition, the vehicle 10 includes a vehicle controller 34 and one or more sensors 40 in communication with the vehicle controller 34. The sensor 40 collects information and generates sensor data indicating the collected information. As non-limiting examples, the sensor 40 may include a global navigation satellite system (GNSS) transceiver or receiver, an inertial measurement unit (IMU), a yaw rate sensor, a ride height sensor, a speed sensor, a lidar, an ultrasonic sensor, and a camera, etc. The GNSS transceiver or receiver is configured to detect the position of the vehicle 10 in the world. The speed sensor is configured to detect the speed of the vehicle 10. The yaw rate sensor is configured to determine the direction of the vehicle 10. The camera may have a field of view large enough to capture images in front, behind, and to the sides of the vehicle 10. The ride height sensor is configured to measure the ride height of the vehicle 10. The ultrasonic sensor may detect static and / or dynamic objects.

[0036] The vehicle controller 34 is programmed to receive sensor data from the sensor 40 and includes at least one processor 44 and a non-transitory computer-readable storage device or medium 46. The processor 44 can be a custom processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor of several processors associated with the vehicle controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), a macroprocessor, a combination thereof, or generally a device for executing instructions. The computer-readable storage device or medium 46 can include volatile and non-volatile storage in, for example, read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables when the processor 44 is powered off. The computer-readable storage device or medium of the vehicle controller 34 can be implemented using a plurality of storage devices, such as PROM (programmable read-only memory), EPROM (electrical PROM), EEPROM (electrically erasable PROM), flash memory, or other electrical, magnetic, optical, or combination storage devices capable of storing data (some of which represent executable instructions used by the vehicle controller 34 when controlling the vehicle 10).

[0037] The instructions may include one or more separate programs, each of which includes an ordered list of executable instructions for implementing logical functions. When executed by the processor 44, the instructions receive and process signals from the camera, execute logic, calculations, methods and / or algorithms for automatically controlling components of the vehicle 10, and generate control signals to actuators (e.g., the first aerodynamic actuator 41 and / or the second aerodynamic actuator 42) to automatically control components of the vehicle 10 based on the logic, calculations, methods and / or algorithms. Although Figure 1 1, but the system 11 may include multiple controllers 34 that communicate via a suitable communication medium or combination of communication media and cooperate to process sensor signals, execute logic, calculations, methods and / or algorithms, and generate control signals to automatically control features of the system 11. In various embodiments, one or more instructions of the vehicle controller 34 are included in the system 11. The non-transitory computer readable storage device or medium 46 includes instructions that, when executed by one or more processors, cause the processor 44 to perform the method 100 ( Figure 2 ) of machine-readable instructions (e.g., Figure 2 shown).

[0038] The vehicle 10 also includes one or more vehicle actuators 47 that control one or more vehicle features, such as, but not limited to, a propulsion system, a transmission system, a steering system, and a braking system. In various embodiments, the vehicle features may also include interior and / or exterior vehicle features, such as, but not limited to, doors, trunks, and cabin features, such as air, music, lighting, etc. As non-limiting examples, the vehicle actuator 47 may be an electronic limited slip differential (eLSD), an electronic all-wheel drive (eAWD) system. The vehicle actuator 47 communicates with the vehicle controller 34. Therefore, the vehicle controller 34 is programmed to control the operation of the vehicle actuator 47.

[0039] The vehicle 10 includes a body 12, a first or rear axle 14, and a second or front axle 16. The front axle 16 and the rear axle 14 are coupled to the body 12. In addition, each of the front axle 16 and the rear axle 14 is configured to rotate relative to the body 12. The vehicle 10 also includes one or more first or front tires 20 coupled to the front axle 16 and one or more second or rear tires 18 coupled to the rear axle 14. As a non-limiting example, the vehicle 10 may include two front tires 20 (e.g., a left front tire and a right front tire) and two rear tires 18 (e.g., a left rear tire and a right rear tire).

[0040] The vehicle 10 may include a first aerodynamic actuator or a rear aerodynamic actuator 41 and a second aerodynamic actuator or a front aerodynamic actuator 42 that communicate with the vehicle controller 34, respectively. The first aerodynamic actuator 41 includes a first aerodynamic body 48, and the second aerodynamic actuator 42 is considered a vehicle actuator 47 and includes a second aerodynamic body 50. Each of the first aerodynamic body 48 and the second aerodynamic body 50 may be configured as an airfoil-shaped airflow deflector. In the present disclosure, the term "airfoil-shaped" is defined as having the shape of a wing, that is, an airfoil having an airfoil shape defined by a streamlined cross-sectional shape that generates lift for flight or propulsion through a fluid. The term "airflow deflector" refers to an aerodynamic device that is capable of disrupting the movement of air over the vehicle 10 when the vehicle 10 is in motion, thereby reducing the drag of the vehicle 10 and / or causing aerodynamic downforce. The term "downforce" refers to a component of force perpendicular to the relative direction of motion of the vehicle 10 (i.e., in the longitudinal direction) toward the road surface 13. For example, the airflow deflector can diffuse the air by increasing the amount of turbulence flowing through it. The first aerodynamic actuator 41 is closer to the rear axle 14 than the front axle 16 to control the rear downforce 43 at or near the rear axle 14. The second aerodynamic actuator 42 is closer to the front axle 16 than the rear axle 14 to control the front downforce 45 at or near the front axle 16. The rear downforce 43 and the front downforce 45 can be determined using sensor data from the sensor 40 (e.g., a ride height sensor).

[0041] The first aerodynamic actuator 41 includes a support 52 directly coupled to the vehicle body 12 and one or more first pivots 54 (e.g., pivot pins, pivot mechanisms, etc.) that pivotally couple the first aerodynamic body 48 to the vehicle body 12. Thus, the first aerodynamic body 48 is movable (e.g., pivotable) relative to the vehicle body 12. The first aerodynamic actuator 41 includes a first motor 56 (or another suitable machine) that communicates with the vehicle controller 34 and is coupled to the first aerodynamic body 48 via the first pivot 54. The vehicle controller 34 is therefore programmed to drive the first motor 56 to move the first aerodynamic body 48 relative to the vehicle body 12.

[0042] The second aerodynamic actuator 42 is coupled to the vehicle body 12 and includes one or more second pivots 58 (e.g., pivot pins, pivot mechanisms, etc.) that pivotally connect the second aerodynamic body 50 to the vehicle body 12. Thus, the second aerodynamic body 50 is movable (e.g., pivotable) relative to the vehicle body 12. The second aerodynamic actuator 42 includes a second motor 60 (or another suitable machine) that communicates with the vehicle controller 34 and is coupled to the second aerodynamic body 50 via the second pivot 58. The vehicle controller 34 is therefore programmed to drive the second motor 60 to move the second aerodynamic body 50 relative to the vehicle body 12.

[0043] The vehicle 10 includes a user interface 23 that communicates with a vehicle controller 34. The user interface 23 can be, for example, a touch screen in a dashboard, and can include, but is not limited to, an alarm, such as one or more speakers that provide audible sounds, tactile feedback in a vehicle seat or other object, one or more displays, one or more microphones, one or more lights, and / or other devices suitable for providing notifications. The user interface 23 is in electronic communication with the vehicle controller 34 and is configured to receive input from a hearing-impaired vehicle occupant 25 (e.g., a vehicle user or a vehicle passenger). For example, the user interface 23 can include a touch screen and / or a button configured to receive input from a vehicle occupant. Therefore, the vehicle controller 34 is configured to receive input from a vehicle occupant via the user interface 23 and provide output (e.g., audible, tactile, and / or visible notifications) to the vehicle occupant.

[0044] Figure 2 is a flow chart of a method 100 for estimating tire longitudinal and lateral forces. In other methods, the effect of longitudinal tire forces on the lateral and yaw dynamics of the vehicle is ignored. Method 100 is a comprehensive estimation method that incorporates the effect of longitudinal forces into the estimation of lateral forces. When the yaw moment generated by the difference at each corner or each side of the vehicle 10 is significant, the effect of longitudinal tire forces on the lateral tire force estimates should not be ignored. As a result, by taking into account the longitudinal tire forces, especially in edge cases of well-behaved vehicles, a more accurate estimate of lateral tire forces is obtained.

[0045] In one aspect of the present disclosure, the method 100 begins at box 102. At box 102, the vehicle controller 34 receives vehicle data. At least some of the vehicle data may be obtained directly or indirectly from the sensors 40. As non-limiting examples, the vehicle data includes vehicle lateral acceleration, vehicle yaw acceleration, front wheel steering angle on the road, rear wheel steering angle on the road, mass of the vehicle 10, location of the vehicle center of gravity 62, distance L from the rear axle 14 to the center of gravity 62, and vehicle lateral acceleration. r , the distance L from the front axle 16 to the center of gravity 62 f , the vehicle speed of the vehicle 10 , the wheel slip at each tire (ie, the front tires 20 and the rear tires 18 ), and the yaw moment generated by the longitudinal force at each tire (ie, the front tires 20 and the rear tires 18 ) of the vehicle 10 . The method 100 then continues to block 104 .

[0046] At box 104, the vehicle controller 34 determines whether three conditions (i.e., criteria) are met (i.e., a detection law). The detection law is used to decide when to use the longitudinal tire forces in the lateral tire force estimation. This portion of the method 100 (i.e., box 104) ensures that the longitudinal forces are only used when: 1) they are accurately estimated, and 2) their impact on the lateral and yaw dynamics is significant enough that they should not be ignored. Therefore, the method 100 always avoids using the longitudinal tire forces in the lateral tire force estimation. The longitudinal tire forces are only used in the lateral tire force estimation when the three conditions are met. If one or more of the three conditions are not met, the method 100 proceeds to box 106. At box 106, the method 100 ends and the longitudinal tire forces are not considered when estimating the lateral tire forces of the vehicle 10. If all three of the above conditions are met, the method 100 proceeds to box 108.

[0047] The first condition is that the absolute value of the maximum wheel slip among all wheel slips at each tire (i.e., the front tires 20 and the rear tires 18) is less than a predetermined wheel slip threshold. To determine whether the first condition is met, the vehicle controller 34 determines the maximum wheel slip among the wheel slips of all tires (i.e., the front tires 20 and the rear tires 18) of the vehicle 10. The vehicle controller 34 then determines the absolute value of the maximum wheel slip. Next, the vehicle controller 34 compares the absolute value of the maximum wheel slip with the predetermined wheel slip threshold to determine whether the absolute value of the maximum wheel slip is less than the predetermined wheel slip threshold. If the absolute value of the maximum wheel slip is less than the predetermined wheel slip threshold, the first condition is met.

[0048] The second condition is that the speed of the vehicle is greater than a predetermined speed threshold. To determine whether the second condition is met, the vehicle controller 34 compares the speed of the vehicle 10 with the predetermined speed threshold to determine whether the speed of the vehicle 10 is greater than the predetermined speed threshold. If the speed of the vehicle 10 is greater than the predetermined speed threshold, the second condition is met.

[0049] The third condition is that the yaw moment generated by the longitudinal force at each tire of the vehicle 10 (i.e., the front tires 20 and the rear tires 18) is greater than a predetermined moment threshold. The yaw moment generated by the longitudinal force at each tire of the vehicle 10 (i.e., the front tires 20 and the rear tires 18) can be determined using the following equation:

[0050]

[0051] in:

[0052] is the yaw moment generated by the tire longitudinal force on the vehicle 10;

[0053] F xf is the concentrated longitudinal force in the front axle 16;

[0054] δ F is the front wheel steering angle on the road;

[0055] L f is the distance from the front axle 16 to the center of gravity 62 of the vehicle 10;

[0056] F xr is the concentrated longitudinal force in the rear axle 14;

[0057] δ R is the rear wheel steering angle on the road;

[0058] L r is the distance from the rear axle 18 to the center of gravity 62 of the vehicle 10 ;

[0059] is the longitudinal force on the right front tire;

[0060] is the longitudinal force on the left front tire;

[0061] L w is the axle track (eg, the distance between the wheel hub flanges on the rear axle 14);

[0062] is the longitudinal force on the right rear tire;

[0063] is the longitudinal force on the left rear tire;

[0064] As described above, it may be useful to determine the yaw moment generated by the longitudinal forces at each tire. Therefore, the vehicle controller 34 may determine the longitudinal tire forces using the following equation:

[0065]

[0066] in:

[0067] i can be left or right to refer to the right or left tire;

[0068] j can be front or rear to refer to the front or rear tires;

[0069] is the longitudinal tire force at tire i (left or right) and j (front or rear);

[0070] η ij is the input observer gain for each wheel speed at each tire i (left or right) and j (front or rear);

[0071] R ij is the effective radius of the tires i (left or right) and j (front or rear);

[0072] is the observer gain for each wheel speed at tire i (left or right) and j (front or rear);

[0073] ω ij is the wheel speed of each tire i (left or right) and j (front or rear); and

[0074] is the observer state at tires i (left or right) and j (front or rear) for each wheel speed.

[0075] At box 104, the vehicle controller 34 determines whether all conditions (i.e., the first condition, the second condition, and the third condition as described above) are met. If one or more conditions are not met, the method 100 proceeds to box 106 and the method 100 ends. If all three conditions are met, the method 100 continues to box 108.

[0076] At box 108, the vehicle controller 34 determines (e.g., estimates) the lateral tire force at each tire (e.g., the front tire 20 and the rear tire 18) of the vehicle 10 using a simplified bicycle model. The lateral tire force determined using the simplified bicycle model may be referred to as a first lateral force. The following equation may be used to determine the lateral tire force:

[0077]

[0078]

[0079] in:

[0080] m is the mass of the vehicle 10;

[0081] a y is the lateral acceleration of the vehicle 10;

[0082] δ F is the front wheel steering angle on the road;

[0083] δ R is the rear wheel steering angle on the road;

[0084] L r is the distance from the rear axle 14 to the center of gravity 62 of the vehicle 10;

[0085] L f is the distance from the front axle 16 to the center of gravity 62 of the vehicle 10;

[0086] I zz is the yaw moment of inertia of the vehicle 10;

[0087] is the yaw acceleration of the vehicle 10;

[0088] Fyf is the concentrated lateral force in the front axle 16; and

[0089] F yr is the concentrated lateral force in the rear axle 14 .

[0090] The vehicle controller 34 also executes block 110. Block 110 may be executed before, after, or simultaneously with block 108.

[0091] At box 110, the vehicle controller 34 determines a dual-track integrated lateral force estimation model (i.e., dual-track model) to determine (e.g., estimate) lateral tire forces at each tire (e.g., front tire 20 and rear tire 18) of the vehicle 10. The lateral tire forces determined using the dual-track model may be referred to as second lateral forces. The following equation may be used to determine the lateral tire forces:

[0092]

[0093]

[0094] in:

[0095] is the yaw moment generated by the difference in tire longitudinal force between the left and right sides of the vehicle 10;

[0096] F yf is the concentrated lateral force in the front axle 16 of the vehicle 10;

[0097] F yr is the concentrated lateral force in the rear axle 14 of the vehicle 10;

[0098] m is the mass of the vehicle;

[0099] a y is the lateral acceleration of the vehicle;

[0100] is the yaw acceleration of the vehicle;

[0101] I zz is the yaw moment of inertia of the vehicle 10;

[0102] is the yaw moment generated by the longitudinal tire force on the vehicle;

[0103] i refers to the left tire or the right tire of the vehicle 10;

[0104] j refers to the front axle or rear axle of the vehicle 10;

[0105] is the tire longitudinal force at bridge j and tire i;

[0106] F xfis the concentrated longitudinal force in the front axle of the vehicle 10;

[0107] δ f is the front wheel steering angle on the road;

[0108] δ R is the rear wheel steering angle on the road;

[0109] L r is the distance from the rear axle 14 to the center of gravity 62 of the vehicle 10 ; and

[0110] L f is the distance from the front axle 16 to the center of gravity 62 of the vehicle 10 .

[0111] After executing frame 108 and frame 110, method 100 proceeds to frame 112. In frame 112, vehicle controller 34 fuses the lateral tire force determined using simplified bicycle model (i.e., first lateral force) and the lateral tire force determined using dual track model (i.e., second lateral force) to determine the third lateral force at each of the plurality of tires of vehicle 10. The third lateral force is more accurate than the first lateral force and the second lateral force previously determined. Vehicle controller 34 may use a fusion algorithm to fuse the lateral tire force determined using simplified bicycle model (i.e., first lateral force) and the lateral tire force determined using dual track model (i.e., second lateral force). The fusion algorithm may include a low pass filter to smooth the transition between the two methods. The first low pass filter has a first convergence rate for reducing edges and a second convergence rate for lifting edges, wherein the first convergence rate is different from the second convergence rate. After using the low pass filter, the fusion algorithm may further include multiplying the lateral tire force determined using the dual track model (i.e., the second lateral force) by a predetermined factor and then adding the lateral tire force determined using the simplified bicycle model (i.e., the first lateral force) to the multiplied result to determine a third lateral force at each of the plurality of tires of the vehicle 10. The method 100 then proceeds to block 114.

[0112] At box 114, the vehicle controller 34 uses the third lateral force at each of the plurality of tires of the vehicle 10 to control one or more actuators. For example, the third lateral force can be used in feedback and feedforward control systems that use tire force estimates. More accurate tire force estimates will affect the performance of these control systems. The third lateral force can also be used to control eLSD and / or eAWD systems.

[0113] Although exemplary embodiments are described above, these embodiments are not intended to describe all possible forms covered by the claims. The words used in the specification are descriptive rather than restrictive words, and it should be understood that various changes can be made without departing from the spirit and scope of the present disclosure. As mentioned above, the features of the various embodiments can be combined to form other embodiments of the currently disclosed system and method, which may not be explicitly described or shown. Although various embodiments may have been described as providing advantages or being preferred in terms of one or more desired characteristics relative to other embodiments or prior art implementations, it is recognized by those of ordinary skill in the art that one or more features or characteristics can be compromised to achieve the desired overall system properties, depending on the specific application and implementation. These properties may include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, maintainability, weight, manufacturability, ease of assembly, etc. Therefore, for one or more features, embodiments described as being less than ideal for other embodiments or prior art implementations are not outside the scope of the present disclosure, and may be desirable for specific applications.

[0114] The drawings are in simplified form and are not to exact scale. Directional terms, such as top, bottom, left, right, upper, above, below, rear, and front, may be used with respect to the drawings for convenience and clarity only. These and similar directional terms should not be construed to limit the scope of the present disclosure in any way.

[0115] Embodiments of the present disclosure are described herein. However, it should be understood that the disclosed embodiments are merely examples, and other embodiments may take various and alternative forms. The drawings are not necessarily to scale, and some features may be magnified or minimized to show the details of a particular component. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but only as a representative basis for teaching those skilled in the art to adopt the currently disclosed system and method in various ways. As will be understood by those of ordinary skill in the art, the various features shown and described with reference to any one of the drawings may be combined with the features shown in one or more other drawings to produce embodiments that are not explicitly shown or described. The combination of features shown provides representative embodiments of typical applications. However, various combinations and modifications of features consistent with the teachings of the present disclosure may be required for specific applications or implementations.

[0116] Embodiments of the present disclosure may be described herein in terms of functional and / or logical block components and various processing steps. It should be understood that such block components may be implemented by hardware, software, and / or firmware components configured to perform a number of specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which may perform various functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that embodiments of the present disclosure may be implemented in conjunction with a plurality of systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0117] For the sake of brevity, technologies related to signal processing, data fusion, signaling, control, and other functional aspects of the system (as well as the various operating components of the system) may not be described in detail herein. In addition, the connecting lines shown in the various figures contained herein are intended to represent example functional relationships and / or physical connections between the various elements. It should be noted that alternative or additional functional relationships or physical connections may exist in the embodiments of the present disclosure.

[0118] This specification is merely illustrative in nature and is in no way intended to limit the present disclosure and its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent after studying the drawings, the specification and the appended claims.

Claims

1. A method for estimating lateral force, comprising: receiving vehicle data of a vehicle, wherein the vehicle includes a plurality of tires; determining a first lateral force at each of a plurality of tires of the vehicle using a bicycle model; determining a second lateral force at each of a plurality of tires of the vehicle using a dual track model; fusing a first lateral force determined using the bicycle model and a second lateral force determined using the dual track model to determine a third lateral force at each of a plurality of tires of the vehicle; and An actuator of the vehicle is controlled using a third lateral force at each of a plurality of tires of the vehicle.

2. The method according to claim 1, wherein: The vehicle data includes a plurality of wheel slips at each of a plurality of tires of the vehicle, and the method further includes: determining a maximum wheel slip among the plurality of wheel slips at each of a plurality of tires of the vehicle; determining an absolute value of the maximum wheel slip; and The absolute value of the maximum wheel slip is compared with a predetermined wheel slip threshold to determine whether the absolute value of the maximum wheel slip is less than the predetermined wheel slip threshold.

3. The method according to claim 2, wherein: The vehicle data includes a speed of the vehicle, and the method further includes: The vehicle speed is compared with a predetermined speed threshold to determine whether the vehicle speed is greater than the predetermined speed threshold.

4. The method according to claim 3, wherein: The vehicle data includes a yaw moment generated by a longitudinal force at each of a plurality of tires of the vehicle, and the method further includes: The yaw moment generated by the longitudinal force at each of the plurality of tires of the vehicle is compared to a predetermined moment threshold to determine whether the yaw moment generated by the longitudinal force at each of the plurality of tires of the vehicle is greater than the predetermined moment threshold.

5. The method according to claim 4, wherein: The first lateral force at each of the plurality of tires of the vehicle and the second lateral force at each of the plurality of tires of the vehicle are determined only in response to determining that: (a) the absolute value of the maximum wheel slip is less than the wheel slip threshold, (b) the vehicle speed is greater than the predetermined speed threshold, and (c) the yaw moment generated by the longitudinal force at each of the plurality of tires of the vehicle is greater than the predetermined moment threshold.

6. The method according to claim 5, wherein: The second lateral force at each of the plurality of tires of the vehicle includes a concentrated lateral force in a front axle of the vehicle, and the dual track model uses the following equation: in: F yf is the concentrated lateral force in the front axle of the vehicle; m is the mass of the vehicle; a y is the lateral acceleration of the vehicle; is the yaw acceleration of the vehicle; L r is the distance from the rear axle to the center of gravity of the vehicle; I zz is the yaw moment of inertia of the vehicle; is the yaw moment generated by the longitudinal tire force on the vehicle; i refers to the left or right tire of the vehicle; j refers to the front axle or rear axle of the vehicle; is the tire longitudinal force at bridge j and tire i; F xf is the concentrated longitudinal force on the front axle of the vehicle; δ f is the front wheel steering angle on the road; and L f is the distance from the front axle to the center of gravity of the vehicle.

7. The method according to claim 6, wherein: The second lateral force at each of the plurality of tires of the vehicle includes a concentrated lateral force in a rear axle of the vehicle, and the dual track model uses the following equation: in: F yr is the concentrated lateral force in the rear axle of the vehicle; m is the mass of the vehicle; a y is the lateral acceleration of the vehicle; is the yaw acceleration of the vehicle; L r is the distance from the rear axle to the center of gravity of the vehicle; I zz is the yaw moment of inertia of the vehicle; is the yaw moment generated by the longitudinal tire force on the vehicle; i refers to the left or right tire of the vehicle; j refers to the front axle or rear axle of the vehicle; is the tire longitudinal force at the bridge j and the tire i; F xr is the concentrated longitudinal force on the rear axle of the vehicle; δ r is the rear wheel steering angle on the road; and L f is the distance from the front axle to the center of gravity of the vehicle.

8. The method according to claim 7, wherein: Fusing the first lateral force determined using the bicycle model and the second lateral force determined using the dual track model includes using a low pass filter.

9. The method according to claim 8, wherein: The low pass filter has a first convergence rate for falling edges, the low pass filter has a second convergence rate for rising edges, and the first convergence rate is different from the second convergence rate.

10. A system for estimating lateral force, comprising: Multiple sensors; Actuator; as well as a controller in communication with the plurality of sensors and the actuator, wherein the controller is programmed to: receiving vehicle data from a sensor of a vehicle, wherein the vehicle includes a plurality of tires; determining a first lateral force at each of a plurality of tires of the vehicle using a bicycle model, determining a second lateral force at each of a plurality of tires of the vehicle using a dual track model; fusing a first lateral force determined using the bicycle model and a second lateral force determined using the dual track model to determine a third lateral force at each of a plurality of tires of the vehicle; and The actuator is controlled using the third lateral force at each of a plurality of tires of the vehicle.

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