Vehicle motion management system and vehicle motion support system

Abstract

To improve controllability of a control system during low speed operation.SOLUTION: The present disclosure relates to a vehicle motion management system and a motion support system for a vehicle. The vehicle motion management system and the motion support system are arranged to control operation of at least one actuator configured to apply a torque to at least one wheel of the vehicle. The vehicle motion management system is configured to transmit a control signal indicative of a desired torque and a wheel speed limit to the motion support system, so that the motion support system is, based on the received signal, configured to transmit an actuator signal to the actuator in order that the actuator generates an operating torque on the at least one wheel without exceeding an actuator rotational speed limit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This disclosure relates to a vehicle motion management system and a motion assistance system for a vehicle. This disclosure also relates to methods and control signals that can be operated by the vehicle motion management system and the motion assistance system for a vehicle. This disclosure is applicable to electric propulsion vehicles. While this disclosure primarily targets truck-type vehicles that use electromechanical propulsion, it is also applicable to other types of vehicles. [Background technology]

[0002] In the vehicle sector, particularly in the area of ​​small, medium, and heavy-duty vehicles commonly referred to as trucks, continuous development is underway regarding various vehicle control functions. These control functions, in particular, are intended to improve vehicle drivability, driver comfort, and safety while driving.

[0003] For example, a system for improving the overall stability of a vehicle is described in WO2017 / 215751. In particular, WO2017 / 215751 describes a wheel controller comprising a vehicle wheel function module arranged to communicate with a tire model generator. The vehicle wheel function module is arranged to determine longitudinal wheel force values ​​based on calculated wheel slip values. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] WO2017 / 215751 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The system described in WO2017 / 215751 offers significant advantages, for example, in terms of the dynamic control of the entire vehicle. However, WO2017 / 215751 still requires further improvement because, under relatively low, i.e., near-zero wheel speed driving conditions, it introduces inconsistencies when calculating wheel slip due to the low wheel speed. In other words, it is desirable to improve the controllability of the control system, at least during low-speed driving.

[0006] Therefore, the purpose of this disclosure is to overcome, at least partially, the aforementioned shortcomings. [Means for solving the problem]

[0007] According to a first aspect, a vehicle motion management system for a vehicle is provided, which is connectable to a motion support system to transmit control signals, and the vehicle motion management system is configured to determine a desired torque for driving the vehicle in the current vehicle driving conditions; determine a wheel slip limit for at least one wheel of the vehicle; determine a wheel speed limit for at least one wheel of the vehicle based on at least the wheel slip limit; and send control signals to the motion support system indicating the desired torque and wheel speed limits.

[0008] The vehicle motion management system and motion assistance system are vehicle control systems, and each control system is arranged to perform various control functions for controlling the driving of the vehicle, particularly for controlling wheel motion. The vehicle motion management system is preferably configured to receive and determine wheel parameters at a high level, i.e., the vehicle motion management system determines desired torque and wheel slip limits in a more generalized manner, while the motion assistance system is arranged as a lower-level control system to translate the parameters received from the vehicle motion management system into appropriate parameters for actuators. The motion assistance system takes into account the current drivetrain state before forwarding actuator signals to the actuators. The current drivetrain state may be related to, for example, the current state of the vehicle transmission, the gear position of the vehicle transmission, or the transmission clutch engagement state.

[0009] The desired torque can be obtained, for example, from the driver of a vehicle who is pressing the accelerator pedal and / or the brake pedal. The desired torque can also be received from a system that autonomously controls the vehicle's propulsion, or from an advanced driver-assistance system (ADAS).

[0010] The wheel slip limit should be interpreted as the maximum allowable wheel slip of at least one wheel during operation. Wheel slip is the amount of relative longitudinal motion, or "slip," between a vehicle's wheel and its contact surface. Wheel slip can be determined as a relationship between the longitudinal velocity of the wheel and the rotational velocity of the wheel, taking the wheel radius into account. Therefore, the wheel speed limit is based on the wheel velocity relative to the road surface as viewed in a wheel-based coordinate system. According to one exemplary embodiment, a vehicle motion management system can be configured to determine the current wheel rotational velocity and the current longitudinal wheel velocity for at least one of the vehicle's wheels, and to determine the wheel slip for at least one wheel based on this current wheel rotational velocity and current longitudinal wheel velocity.

[0011] This disclosure is based on the insight that the calculation of the wheel slip limit can be performed by a higher-level vehicle motion management system by sending a control signal indicating a desired torque in combination with the wheel speed limit to the motion assistance system. When calculating wheel slip, the denominator of the wheel slip calculation formula consists of the rotational speed of the wheel. Therefore, when the vehicle is operating at low speeds, the denominator is close to zero or approaches zero, which can cause errors when calculating wheel slip. Thus, performing the wheel slip calculation in a higher-level vehicle motion management system is advantageous because it avoids potential inconsistencies in wheel slip calculations performed by a separate motion assistance system. This results in improved wheel slip consistency.

[0012] Furthermore, sending control signals to the motion support system indicating desired torque and wheel speed limits is particularly advantageous when driving a vehicle using electromechanics, because the electromechanics can control speed and torque. In contrast to slip control, speed control can also be easily achieved, for example, with service brakes. This is because rotational speed is the output commonly used in tire torque balance systems and does not involve any of the nonlinearities present in the wheel slip calculation formulas.

[0013] According to one exemplary embodiment, the wheel speed limit can further be based on a desired torque. This means that the desired torque, i.e., the torque requirement, is used to calculate the slip limit used when calculating the wheel speed limit.

[0014] According to one exemplary embodiment, the wheel speed limits may include an upper wheel speed limit and a lower wheel speed limit. The vehicle motion management system may further be configured to transmit the upper wheel speed limit to the motion support system when at least the desired torque is greater than zero, and to transmit the lower wheel speed limit to the motion support system when at least the desired torque is less than zero.

[0015] One advantage is that different wheel speed limits can be used in response to vehicle acceleration or vehicle deceleration.

[0016] According to an exemplary embodiment, the vehicle motion management system can further determine an offset wheel speed parameter, obtain a signal indicating the wheel speed of the vehicle, and determine a wheel slip limit based on the offset wheel speed parameter when the wheel speed is less than a threshold vehicle speed limit.

[0017] The offset wheel speed parameter is advantageously used when the wheel speed is relatively low, such as close to zero. As described above, since the wheel slip limit is the denominator of the wheel slip calculation formula, it may be difficult to calculate correctly at low speeds. Therefore, setting the offset wheel speed parameter advantageously improves this potential inconsistency. The offset wheel speed parameter can be an upper offset wheel speed parameter and a lower offset wheel speed parameter, where the upper offset wheel speed parameter is higher than the current vehicle speed and the lower offset wheel speed parameter is lower than the current vehicle speed. The offset wheel speed parameter can be obtained by mapping the offset wheel speed parameter to a desired torque using a tire model.

[0018] According to an exemplary embodiment, the wheel slip limit can be within a predetermined wheel slip range. This prevents the vehicle's wheels from being subjected to overly severe or overly low wheel slip.

[0019] According to an exemplary embodiment, the vehicle motion management system can further be configured to obtain a signal indicating the current accelerator pedal position of the vehicle and determine a desired torque based on the current accelerator pedal position. However, according to an exemplary embodiment, the desired torque can alternatively be determined based on a signal received from the autonomous vehicle driving system. According to another alternative shown above, the vehicle motion management system can be configured to obtain a signal indicating the brake pedal position for determining the desired torque or from the so-called retarder stalk position of the vehicle's retarder. Thus, the vehicle motion management system can be arranged in an autonomously controlled vehicle as well as in a driver-controlled vehicle.

[0020] According to an exemplary embodiment, the vehicle motion management system can further be configured to determine a wheel friction level between at least one wheel and the road surface and determine the current vehicle driving state based on the determined wheel friction level. Other alternatives for determining the current vehicle driving state, such as the current vehicle weight, i.e., the weight of the loaded vehicle, and the road topology on which the vehicle is currently being driven, can also be used as input parameters when determining the current vehicle driving state, either as an alternative or in combination with the wheel friction level.

[0021] According to a second embodiment, a vehicle motion assistance system is provided, which is connectable to the aforementioned vehicle motion management system and at least one actuator configured to apply torque to at least one wheel of the vehicle, the motion assistance system being configured to receive a control signal from the vehicle motion management system, the control signal indicating a desired torque for driving the vehicle in the current vehicle driving state and a wheel speed limit for at least one wheel of the vehicle, the motion assistance system being further configured to determine the current vehicle drive system state of the vehicle, and to determine an operating torque and an actuator rotation speed limit based on the current vehicle drive system state, the desired torque and wheel speed limit; and to send an actuator signal to the actuator so that the actuator generates an operating torque to at least one wheel without exceeding the actuator rotation speed limit.

[0022] The current drivetrain state should be interpreted as the current operating mode of the drivetrain, particularly the drivetrain's transmission. According to one exemplary embodiment, the current vehicle drivetrain state may be one of the following: the current vehicle transmission state, the gear position of the vehicle transmission, or the transmission clutch engagement state. Thus, as previously shown, the motion assistance system is positioned as a subordinate control system configured to translate parameters received from the vehicle motion management system into appropriate parameters for the actuators, taking the current drivetrain state into account.

[0023] According to one exemplary embodiment, the motion support system may be a distributed motion support system that can be connected to a wheel-specific actuator configured to control a single wheel of a vehicle.

[0024] Using a distributed motion assistance system enables rapid response to dedicated actuators connected to it, thereby improving the vehicle's driving propulsion and braking performance. The distributed motion assistance system can be connected to a separate vehicle motion management system or to a central vehicle motion management system, which in turn connects to multiple distributed motion assistance systems.

[0025] Further features and effects of the second embodiment are broadly similar to those described above in relation to the first embodiment. The first and second embodiments thus provide a vehicle control system comprising a vehicle motion management system defined by any one embodiment of the first embodiment and a motion support system defined by any one embodiment of the second embodiment.

[0026] According to a third aspect, a method is provided for controlling an actuator of a vehicle, the actuator configured to apply torque to at least one wheel of the vehicle, the method comprising: determining a desired torque for driving the vehicle in the current vehicle driving conditions; determining a wheel slip limit for at least one wheel of the vehicle; determining a wheel speed limit for at least one wheel of the vehicle based on at least the wheel slip limits; determining an operating torque and an actuator rotational speed limit based on the desired torque, the wheel speed limit and the current vehicle drivetrain conditions; and controlling the actuator to generate an operating torque on at least one wheel without exceeding the actuator's rotational speed limit.

[0027] The features and effects of the third embodiment are broadly similar to those described above in relation to the first and second embodiments. Therefore, the features described above in relation to the vehicle motion management system and motion support system apply to the method described for the third embodiment.

[0028] According to a fourth aspect, a control signal is provided that represents a command to be executed by the motion support system, the control signal includes a torque component that enables the motion support system to determine an operating torque and a wheel speed limit component that represents wheel speed limit data, which, when executed by the motion support system, causes the motion support system to generate an actuator signal corresponding to the operating torque according to an actuator rotation speed limit, which can be determined based on the wheel speed limit component taking into account the current state of the vehicle drivetrain.

[0029] According to the fifth aspect, a computer program is provided, which includes program code means for performing the steps of the third aspect when the program is executed on a computer.

[0030] According to the sixth aspect, a computer-readable medium is provided that holds a computer program which includes a program means for performing the steps of the third aspect when the program means is executed on a computer.

[0031] The features and effects of the fourth, fifth, and sixth embodiments are broadly similar to those described above in relation to the first and second embodiments.

[0032] Further features and advantages will become apparent upon consideration of the attached claims and the following description. Those skilled in the art will understand that, without departing from the scope of this disclosure, different features can be combined to create embodiments other than those described below.

[0033] The foregoing, as well as any additional purposes, features, and benefits, will be better understood by the following descriptive and non-limiting detailed description of exemplary embodiments. [Brief explanation of the drawing]

[0034] [Figure 1] This is a side view showing an exemplary embodiment of a vehicle in the form of a truck. [Figure 2] This is a schematic diagram of a vehicle motion management system and motion support system according to an exemplary embodiment. [Figure 3] This graph shows an exemplary embodiment of a model illustrating the relationship between wheel slip and tire force. [Figure 4] This is a flowchart illustrating a method for controlling the actuator of the vehicle shown in Figure 1, according to one exemplary embodiment. [Modes for carrying out the invention]

[0035] Next, the present disclosure will be described more fully below with reference to the accompanying drawings illustrating exemplary embodiments. However, since the present disclosure can be embodied in many different forms, it should not be construed as being limited to the embodiments described herein, but rather these embodiments are presented for thoroughness and completeness. The same reference letters refer to the same elements throughout the specification.

[0036] Referring particularly to Figure 1, a vehicle 100 in the form of a truck is shown. This vehicle has a plurality of wheels 102, each wheel 102 having its own actuator 104. In the embodiment shown in Figure 1, an actuator is illustrated for each wheel 102, but it will be readily apparent that, for example, a pair of wheels 102 can be arranged without such actuators 104. Furthermore, it is preferable that the actuators 104 are actuators for controlling each wheel propulsion device, such as an electromachine 106 arranged to impart tire force to the wheels of the vehicle 100, as shown in Figure 3 and further described below. Thus, such an electromachine can be adapted to generate propulsion torque and can also be arranged in a regenerative braking mode to charge the vehicle 100's battery (not shown) or other energy storage system. The electromachine can also generate braking torque without storing energy. For example, excess energy from the electromachine during braking can be dissipated using a brake resistor or the like.

[0037] Furthermore, each actuator 104 is connected to a corresponding motion support system 300, which is configured to control the operation of the actuator 104. The motion support system 300 is preferably a distributed motion support system 300, but a centralized embodiment is also possible. It should be understood that some parts of the motion support system are remote from the vehicle and cannot implement processing circuits, such as on a remote server accessible from the vehicle via a wireless link. Furthermore, each motion support system 300 is connected to the vehicle motion management system 200 of the vehicle 100 via a data bus communication configuration 114, etc. This allows control signals to be transmitted between the vehicle motion management system 200 and the motion support systems 300. The vehicle motion management system 200 and the motion support systems 300 will be described in more detail below with reference to Figure 2.

[0038] The vehicle motion management system 200 and motion support system 300 may include a microprocessor, microcontroller, programmable digital signal processor, or other programmable device. The system may further or alternatively include application-specific integrated circuits, programmable gate arrays or programmable array logic, programmable logic devices, or digital signal processors. If the system includes programmable devices such as the microprocessor, microcontroller, or programmable digital signal processor described above, the processor may further include computer executable code that controls the operation of the programmable device.

[0039] Referring to Figure 2, Figure 2 is a schematic diagram of a vehicle motion management system 200 and motion support system 300 according to an exemplary embodiment. That is, the vehicle motion management system 200 and motion support system 300 form part of the vehicle motion system 500.

[0040] The entire vehicle control system can be implemented in one or more vehicle unit computers (VUCs). The VUCs can be configured to perform vehicle control methods organized according to a hierarchical functional architecture, in which case some functions may be included in the higher-level traffic condition management (TSM) domain, and some other functions may be included in the lower-level vehicle motion management (VMM) domain.

[0041] Figure 2 schematically illustrates the functionality for controlling one or more wheels by several exemplary motion assistance devices (MSDs), such as friction brakes and propulsion devices. Friction brakes and propulsion devices are examples of wheel torque generating devices, sometimes called actuators, which can be controlled by one or more motion assistance device control units. This control is based on measurement data obtained, for example, from wheel speed sensors, other vehicle state sensors such as radar sensors and lidar sensors, and vision-based sensors such as camera sensors and infrared detectors. Other exemplary torque-generating motion assistance devices that can be controlled according to the principles discussed herein include engine retarders and power steering devices. One MSD control unit may be configured to control one or more actuators. For example, it is not uncommon for one MSD control unit to be configured to control both wheels on a given axle.

[0042] The TSM function plans driving operations for a planned period of, for example, 10 seconds. This time frame corresponds, for example, to the time required for the vehicle to pass through a curve. The vehicle operations planned and executed by the TSM can be associated with acceleration profiles and curvature profiles that describe the desired vehicle speed and turning for a given operation. The TSM then assigns the desired acceleration profile a to the VMM function, which distributes forces to safely and robustly meet the requirements from the TSM. req and curvature profile c req They will continue to demand it.

[0043] Acceleration and curvature profiles can also be obtained from the driver of a large vehicle via conventional control input devices such as the steering wheel, accelerator pedal, and brake pedal.

[0044] The VMM function operates for a planning period of approximately 1 second, and the acceleration profile a req and curvature profile c req The VMM continuously converts this into control commands to control vehicle motion functions driven by separate MSDs of vehicle 100, which report their functions to the VMM, and these control commands are used as constraints in vehicle control. The VMM function estimates the vehicle state or motion. That is, the VMM function continuously determines the vehicle state, including the position, velocity, acceleration, and coupling angle of different units in the vehicle combination, through monitoring operations using various sensors located in vehicle 100, which are not always but often connected to the MSDs.

[0045] The results of the motion estimation, i.e., the estimated vehicle state, can be input to the force generation module, which then generates the requested acceleration profile a req and curvature profile c req To make vehicle 100 move accordingly, the total forces required for different vehicle units are determined. The required total force vectors are input into an MSD adjustment function that assigns wheel forces and adjusts other MSDs such as steering and suspension. Then, each adjusted MSD together provides the desired lateral force Fy and longitudinal force Fx, as well as the required moment Mz, to the vehicle unit to obtain the desired motion of the vehicle combination.

[0046] By determining vehicle unit motion using a global positioning system, vision-based sensors, wheel speed sensors, radar sensors, lidar sensors, etc., and transforming this vehicle unit motion into a local coordinate system of a given wheel (for example, with respect to longitudinal and lateral velocity components), it becomes possible to accurately estimate wheel slip by comparing the vehicle unit motion in the wheel reference coordinate system with data obtained from wheel speed sensors positioned coupled to the wheel.

[0047] The tire model discussed below in more detail in relation to Figure 3 is the desired longitudinal tire force Fx i It can be used to convert between and wheel slip. Wheel slip is related to the difference in speed between the wheel rotation speed and the ground, which will be discussed in detail below. Wheel speed is the rotational speed of the wheel, given, for example, in revolutions per minute (rpm), or in angular velocity converted to radians per second (rad / s) or degrees per second (deg / s).

[0048] In this specification, a tire model is a wheel behavior model that describes the wheel forces acting in the longitudinal (rolling direction) and / or lateral (directions perpendicular to the longitudinal direction) as a function of wheel slip. In "Tyre and vehicle dynamics," Elsevier Ltd., 2012, ISBN 978-0-08-097016-5, Hans Pacejka discusses the fundamentals of the tire model. For example, see Chapter 7, which discusses the relationship between wheel slip and longitudinal forces.

[0049] In summary, the VMM function manages both force generation and MSD adjustment. That is, the VMM function determines how much force is required of the vehicle unit to fulfill the requirements from the TSM function, for example, to accelerate the vehicle according to the required acceleration profile as requested by the TSM, and / or to generate motion of a specific curvature by the vehicle as further requested by the TSM. This force may include, for example, the yaw moment Mz, the longitudinal force Fx, the lateral force Fy, and different types of torque to be applied to separate wheels.

[0050] The VMM is positioned as a higher-level control system, and the MSD is positioned as a lower-level control system. Therefore, the higher-level VMM 200 is positioned to determine various parameters in the vehicle / wheel domain, i.e., based on the overall state of the vehicle, such as vehicle speed, as will be discussed below. On the other hand, the lower-level MSD 300 is positioned to determine parameters specific to the actuators connected to the wheels. Therefore, the lower-level MSD converts the signals received from the higher-level VMM into the actuator domain, taking into account, for example, gear ratio and drivetrain inertia.

[0051] In a non-limiting example, the vehicle motion management system 200 comprises a torque module 202, a wheel slip module 204, and a friction module 206. The vehicle motion management system 200 is further arranged to receive vehicle operation signals 502 containing data that can be operated by the vehicle motion management system 200 and its various modules 202, 204, and 206. The vehicle operation signals 502 supplied to the vehicle motion management system 200 may include data in the form of signals indicating, for example, the vehicle's current environment, current traffic conditions, and vehicle weight parameters such as whether the vehicle is loaded, unloaded, or partially loaded. The vehicle motion management system 200 may also receive other signals indicating specific vehicle conditions, such as the current vehicle driving state, as will be discussed below. The torque module 202, the wheel slip module 204, and the friction module 206 are configured to transmit communication signals between themselves. That is, these separate modules are configured to communicate with each other as will be revealed in the following disclosure. It will be readily apparent that the torque module 202, the wheel slip module 204, and the friction module 206 are illustrated as separate components for illustrative purposes only. The vehicle motion management system 200 can also, of course, easily incorporate various control functions that perform the functions described below.

[0052] Next, the functional operation of the vehicle motion management system 200 will be described. In particular, the vehicle motion management system 200 is configured to receive input signals containing information related to the current vehicle driving state. The current vehicle driving state may include, for example, the wheel friction level between the vehicle's wheels and the road surface, or the vehicle's current weight, i.e., whether the vehicle is loaded, unloaded, or partially loaded, or data indicating the topology of the road on which the vehicle is currently driving. Thus, various driving states can be received by the vehicle motion management system 200 as individual components, or as a component using all different driving states as a whole. Different driving states of the vehicle can be determined using appropriate sensors and transmitted to the vehicle motion management system 200.

[0053] As described above, the vehicle motion management system 200 further comprises a friction module 206. According to one exemplary embodiment, the vehicle motion management system 200 is configured to use the friction module 206 to determine the wheel friction level between at least one wheel and the road surface. Based on the determined wheel friction level, the vehicle motion management system 200 can determine the current vehicle driving state.

[0054] The torque module 202 is adapted to determine the desired torque for driving the vehicle in the current vehicle driving conditions. This allows the vehicle motion management system 200, in the aforementioned higher-level vehicle motion management system 200, to determine the torque requirements for properly controlling the vehicle 100 in the current driving conditions.

[0055] The desired torque can be determined, for example, based on the current position of the accelerator pedal, the position of the brake pedal, or based on signals received from the autonomous vehicle driving system.

[0056] The wheel slip module 204 is arranged to determine the wheel slip limit of at least one wheel 102 of the vehicle 100. That is, the maximum allowable wheel slip of the vehicle is determined, and the wheels of the vehicle are not allowed to exceed such a wheel slip limit. The wheel slip can be determined, for example, as a non-limiting example, based on the following formula (Equation 1).

[0057]

Equation

[0058] The wheel slip limit can be determined, for example, using the model 350 discussed below in relation to FIG. 3. Thereby, the vehicle motion management system 200 can convert the force demand into a slip demand, whereby the slip limit is set based on the slip demand. According to another example, the slip limit can be set as a fixed value independently of the force demand. The slip limit can also be based on a signal indicating the current friction level between the road surface and the tire surface.

[0059] <( Based on the wheel slip limit, the wheel slip module 204 is configured to determine the wheel speed limit of at least one wheel. Thereby, the vehicle motion management system 200 performs the calculation of the wheel slip limit and the calculation of the wheel speed limit. According to a non-limiting example, the wheel speed limit value ω w,sl can be determined based on the following formula (Equation 2).

[0060]

Equation

[0061] When the wheel speed is relatively low, i.e., close to zero, the vehicle motion management system 200 can be configured to determine wheel slip based on the offset wheel speed parameter, thereby allowing the offset wheel speed limit to be calculated according to the non-restrictive equation (3). ω w,ol =V x,w / Rw+max(|λ lim |k ol ,ω w,ol,max )sgn(λ) (3) Here, ω w,ol This is the wheel speed limit calculated from the speed offset limit, k ol,ω and ω ol,max These are the gain and maximum speed offset parameters used to convert the slip limit to the offset limit. sgn(λ) is a signum function that is equal to 1 during acceleration and equal to -1 during deceleration.

[0062] Furthermore, the wheel speed limit may include an upper wheel speed limit and a lower wheel speed limit. The upper wheel speed limit is used during acceleration, i.e., propulsion, and the lower wheel speed limit is used during deceleration, i.e., braking. The upper wheel speed limit is used when the wheel slip limit is positive and the desired torque is greater than zero, i.e., during acceleration, and the lower wheel speed limit is used when the wheel slip limit is negative and the desired torque is less than zero, i.e., during deceleration. The wheel slip limit is also within a predetermined range defined by the following equation. -1<λ lim <1

[0063] The characteristics of wheel slip with respect to longitudinal and lateral tire forces are shown in Figure 3. Specifically, Figure 3 shows Model 350, which represents the relationship between the calculated longitudinal wheel slip and the estimated longitudinal tire force, and Model 450, which represents the relationship between the maximum available lateral tire force for a given longitudinal wheel slip. Model 450 can also represent the lateral tire force obtained for a given longitudinal wheel slip for a given lateral slip angle of the tire. The longitudinal axis 340 represents the tire force generated between the road surface supporting the wheel 102 and the wheel, and the lateral axis 330 represents the longitudinal wheel slip of the wheel 102 as defined above by Equation (Equation 1).

[0064] Referring again to Figure 2, once the wheel speed limit and the desired torque are determined, the vehicle motion management system 200 sends a control signal 550 to the motion support system 300, which indicates the desired torque and wheel speed limit.

[0065] The motion support system 300 comprises a drivetrain state module 302 and an actuator torque module 304. As previously mentioned in relation to the vehicle motion management system 200, the drivetrain state module 302 and the actuator torque module 304 are shown simply as separate components for illustrative purposes. The motion support system 300 can also, of course, easily incorporate various control functions that perform the functions described below.

[0066] As described above, the motion support system 300 receives a control signal 550 from the vehicle motion management system 200. The drivetrain state module 302 determines the current drivetrain state of the vehicle 100. The current drivetrain state may relate to, for example, the current vehicle transmission state, the gear position of the vehicle transmission, the transmission clutch operation state, etc.

[0067] The actuator torque module 304 is configured to determine the actuator's intrinsic torque, that is, to convert the desired torque data from the vehicle motion management system 200 into data relevant to the actuator 104. Specifically, the actuator torque module 304 determines the operating torque based on the desired torque received from the vehicle motion management system 200, and also based on the current drivetrain state of the vehicle 100.

[0068] The actuator torque module 304 also determines the actuator rotation speed limit of actuator 104. The actuator rotation speed limit is based on the wheel speed limit received from the vehicle motion management system 200. The actuator rotation speed limit can also be based on the current drivetrain state. Thus, the motion support system 300 converts the wheel speed limit received from the vehicle motion management system 200 into a wheel-specific wheel rotation speed limit.

[0069] Subsequently, the motion support system 300 sends an actuator control signal 590 to the actuator 104, generating operating torque on the wheel 102 without exceeding the actuator rotation speed limit.

[0070] Refer to Figure 4 for a summary. This figure shows a flowchart of a method for controlling an actuator 104 of a vehicle 100 according to an exemplary embodiment. While the vehicle 100 is in operation, a desired torque for driving the vehicle 100 in the current vehicle driving state is determined (S1). As previously stated, the desired torque can be determined based on an input signal from the accelerator pedal of the vehicle 100, or an input signal from an autonomous vehicle driving system, or an input signal from any advanced driver assistance system (ADAS) implemented in the vehicle 100. The current vehicle driving state may include data indicating the wheel friction level between the vehicle's wheels and the road surface, the current weight of the vehicle, the topology of the road on which the vehicle is currently driving, etc., as previously stated.

[0071] Furthermore, the wheel slip limit is determined (S2), and based on the determined wheel slip limit, the wheel speed limit for at least one wheel 102 is determined (S3). Based on the desired torque, wheel speed limit, and current vehicle drivetrain state, the operating torque and allowable actuator rotational speed range can be determined (S4). This determines the actuator-specific parameters.

[0072] Finally, the actuator is controlled to generate an operating torque for at least one wheel 102 without exceeding the actuator rotation speed limit (S5). In this way, as long as the actuator rotation speed is kept within the permissible range, the operating torque can be generated by torque control.

[0073] It should be understood that this disclosure is not limited to the embodiments described above and illustrated. Rather, those skilled in the art will understand that many changes and modifications may be made within the scope of the appended claims. [Explanation of symbols]

[0074] 100...vehicles 102...Wheel 104… Actuator 106… Electrical machinery 114...Data bus communication configuration 200... Vehicle motion management system 202... Torque module 204...Wheel slip module 206… Friction Module 300... Exercise support system 302…Drive System Status Module 304…Actuator Torque Module 330... Horizontal axis 340…Vertical axis 350... Model 450... Model 500... Vehicle motion system 502... Vehicle operation signal 550... Control signal 590... Actuator control signal

Claims

1. A vehicle motion management system (200) for vehicles, It can be connected to a motor support system (300) to transmit control signals. To determine the desired torque for driving the vehicle under its current operating conditions, Determining the wheel slip limit for at least one wheel of the vehicle, Determining a wheel speed limit for at least one wheel of the vehicle based on at least the wheel slip limit and the desired torque, wherein the wheel speed limit includes an upper wheel speed limit and a lower wheel speed limit. Sending a control signal indicating the desired torque, When the desired torque is greater than zero, the upper wheel speed limit is transmitted to the motion support system. When the desired torque is less than zero, the lower wheel speed limit is transmitted to the motion support system. A vehicle motion management system (200) configured to perform the following.

2. Determining the offset wheel speed parameter, wherein the offset wheel speed parameter is the speed offset limit, To acquire a signal indicating the wheel speed of the aforementioned vehicle, When the wheel speed is less than the threshold vehicle speed limit, the wheel slip limit is determined based on the offset wheel speed parameter, A vehicle motion management system (200) according to claim 1, further configured to perform the following.

3. To determine the current wheel rotation speed and the current longitudinal wheel speed for at least one of the wheels of the vehicle, Based on the current wheel rotation speed and the current longitudinal wheel speed, the wheel slip of at least one wheel is determined. A vehicle motion management system (200) according to any one of claim 1 or 2, further configured to perform the following:

4. The vehicle motion management system (200) according to any one of claims 1 to 3, wherein the wheel slip limit is within a predetermined range of wheel slip.

5. To acquire a signal indicating the current accelerator pedal position of the vehicle's accelerator pedal, The desired torque is determined based on the current accelerator pedal position, A vehicle motion management system (200) according to any one of claims 1 to 4, further configured to perform the following:

6. A vehicle motion management system (200) according to any one of claims 1 to 4, wherein the desired torque is determined based on a signal received from an autonomous vehicle driving system.

7. Determining the wheel friction level between at least one wheel and the road surface, Based on the wheel friction level determined above, the current vehicle operating state is determined, A vehicle motion management system (200) according to any one of claims 1 to 6, further configured to perform the following:

8. A vehicle motion support system (300), It is connectable to a vehicle motion management system (200) and at least one actuator (104) configured to apply torque to at least one wheel of the vehicle. Receiving a control signal from a vehicle motion management system (200), wherein the control signal indicates a desired torque for driving the vehicle in the current vehicle driving state and a wheel speed limit for at least one wheel of the vehicle, and the wheel speed limit includes an upper wheel speed limit received from the vehicle motion management system when the desired torque is greater than zero and a lower wheel speed limit received from the vehicle motion management system when the desired torque is less than zero. To determine the current state of the vehicle's drivetrain, Based on the current vehicle drivetrain state, the desired torque, and the wheel speed limit, the operating torque and actuator rotational speed limit are determined. To ensure that the actuator generates the operating torque for at least one wheel without exceeding the actuator rotation speed limit, an actuator signal is sent to the actuator (104), An exercise support system (300) configured to perform the following.

9. The motion support system (300) according to claim 8, wherein the current vehicle drivetrain state is one of the current vehicle transmission state, the gear position of the vehicle transmission, or the transmission clutch operating state.

10. A distributed motion support system (300) according to any one of claims 8 or 9, which can be connected to a wheel-specific actuator configured to control a single wheel of the vehicle.

11. A method for controlling an actuator for a vehicle, The actuator is configured to apply torque to at least one wheel (102) of the vehicle. Step (S1) of determining a desired torque for driving the vehicle in the current vehicle driving conditions, Step (S2) of determining the wheel slip limit for at least one wheel of the vehicle, A step (S3) of determining a wheel speed limit for at least one wheel of the vehicle based on at least the wheel slip limit and the desired torque, wherein the wheel speed limit includes an upper wheel speed limit determined when the desired torque is greater than zero and a lower wheel speed limit determined when the desired torque is less than zero, Step (S4) of determining the operating torque and actuator rotational speed limit based on the desired torque, the wheel speed limit, and the current state of the vehicle drive system, Step (S5) of controlling the actuator to generate the operating torque on at least one of the wheels without exceeding the rotational speed limit of the actuator, Methods that include...

12. A computer program comprising program code means for performing the steps described in claim 11 when executed on a computer.

13. A computer-readable medium holding a computer program which includes programming means for performing the steps described in claim 11 when executed on a computer.

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