Vehicle driving assistance methods and driving assistance units

Abstract

Embodiments of the present invention provide a vehicle driving assistance method and a driving assistance unit. The driving assistance unit includes: a first detection module configured to detect whether each wheel is a stable wheel or an unstable wheel based on the slip ratio of each wheel, to obtain a first detection result; a second detection module configured to detect whether the suspension of each wheel is in a compressed state or a stretched state based on the suspension travel of each wheel, and to detect the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle, to obtain a second detection result; and a decision module configured to determine a driving assistance strategy based on the first detection result and the second detection result.

Description

Technical Field

[0001] This invention generally relates to the technical field of vehicle driving assistance. Specifically, this invention relates to a driving assistance method and a driving assistance unit for a vehicle. Background Technology

[0002] When vehicles travel on challenging terrains such as snow or rocks, their mobility is limited. This is particularly pronounced in electric vehicles, as their motors can generate significant driving torque at low speeds, easily causing the wheels to lose traction and slip. One solution to this challenge is to rely on the driver's skill to navigate the terrain, which undoubtedly places high demands on the driver's control and reduces the vehicle's ease of use. Another solution, for vehicles equipped with multiple control modes suitable for different road conditions, involves the driver manually switching to the appropriate mode. However, this not only increases the driver's workload but may also cause delays in control due to the time required for mode switching. Summary of the Invention

[0003] In this context, the present invention aims to provide a vehicle driving assistance solution that provides an adaptive control scheme by detecting wheel stability and the tension or compression of the wheel suspension, thereby automatically executing a control strategy adapted to the current road conditions.

[0004] According to one embodiment of the present invention, a driving assistance unit for a vehicle is provided, comprising: a first detection module configured to detect whether each wheel is a stable wheel or an unstable wheel based on the slip ratio of each wheel, to obtain a first detection result; a second detection module configured to detect whether the suspension of each wheel is in a compressed state or a stretched state based on the suspension travel of each wheel, and to detect the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle, to obtain a second detection result; and a decision module configured to determine a driving assistance strategy based on the first detection result and the second detection result; wherein, in the first detection result, all four wheels are unstable. If the first detection result is that all four wheels are unstable and the second detection result is that the acceleration difference is greater than a first threshold value, then the driving assistance strategy is a first driving assistance strategy; and if the first detection result is that at least one wheel is stable and the second detection result is that at least one wheel is in a state of tension or compression, or if the first detection result is that at least one wheel is stable and the second detection result is that the acceleration difference is greater than a first threshold value, then the driving assistance strategy is a second driving assistance strategy.

[0005] According to another aspect of the present invention, a vehicle is provided, including a driving assistance unit according to an embodiment of the present invention.

[0006] According to another embodiment of the present invention, a driving assistance method for a vehicle is provided, comprising: detecting whether each wheel is a stable wheel or an unstable wheel based on the wheel speed or slip ratio of each wheel to obtain a first detection result; detecting whether the suspension of each wheel is in a compression state or a tension state based on the suspension travel of each wheel, and detecting the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle to obtain a second detection result; determining a driving assistance strategy based on the first detection result and the second detection result; wherein, if the first detection result is that all four wheels are unstable wheels and the second detection result is that at least one wheel suspension is in a compression state or a tension state; or, if the first detection result is that all four wheels are unstable wheels and the second detection result is that the acceleration difference is greater than a first threshold value of acceleration difference, the driving assistance strategy is a first driving assistance strategy; and if the first detection result is that there is at least one stable wheel and the second detection result is that at least one wheel suspension is in a tension state or a compression state; or, if the first detection result is that there is at least one stable wheel and the second detection result is that the acceleration difference is greater than a first threshold value of acceleration difference, the driving assistance strategy is a second driving assistance strategy.

[0007] According to another aspect of the present invention, a computer program product is provided, comprising computer-executable instructions that, when executed, cause one or more processors to perform a driving assistance method according to an embodiment of the present invention. Attached Figure Description

[0008] The technical solution of the present invention will become clearer from the following detailed description taken in conjunction with the accompanying drawings. It is to be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0009] Figure 1 This is a schematic block diagram of a driving assistance system according to an embodiment of the present invention, including a driving assistance unit according to an embodiment of the present invention.

[0010] Figure 2 A flowchart of a driving assistance method according to an embodiment of the present invention. Detailed Implementation

[0011] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0012] Figure 1A driving assistance system 100 (referred to as "system 100" in some places below) according to an embodiment of the present invention is shown, which includes a sensor unit 10, a driving assistance unit 20 and an execution unit 30.

[0013] The sensor unit 10 is used to provide information related to the vehicle's driving status. This information includes, for example, vehicle speed (e.g., speed in the direction of travel), wheel speeds and accelerations of each wheel, slip ratios of each wheel, suspension travel of each wheel, steering wheel angle, etc.

[0014] Vehicle driving status information can be obtained directly from sensor measurements or calculated from those measurements. For example, steering wheel angle can be directly obtained from steering wheel angle sensor measurements. Wheel slip ratio can be obtained by calculating the ratio of the difference between the vehicle speed and wheel speed measured by sensors to the vehicle speed.

[0015] In one embodiment, the sensor unit 10 may include sensors for sensing parameters such as vehicle speed, wheel speed, and steering wheel angle, and may also include sensors for receiving information data from outside the vehicle, such as receiving information related to the vehicle's driving status from an edge cloud or cloud server via V2X communication.

[0016] The driving assistance unit 20 is communicatively connected to the sensor unit 10 to acquire information related to the vehicle's driving status. Based on the acquired information, the driving assistance unit 20 detects the stability status of each wheel and the compression or extension status of the suspension at each wheel, and decides on appropriate driving assistance strategies based on the detection results. Furthermore, the driving assistance unit 20 can also determine the road surface type based on the detection results and formulate driving assistance strategies adapted to the road surface type, thereby providing a rapid and accurate response to the current road conditions.

[0017] In embodiments of the present invention, a "stable wheel" refers to a wheel that maintains normal rotation without slipping; an "unstable wheel" refers to a wheel that slips during rotation.

[0018] In embodiments of the present invention, "wheel suspension in a compressed state" means that, compared to when the vehicle is stationary on a level road surface, the wheel suspension travel is shortened and maintained in this shortened state for a predetermined duration; that is, the wheel suspension is compressed for more than the predetermined duration. "Wheel suspension in a stretched state" means that, compared to when the vehicle is stationary on a level road surface, the wheel suspension travel is increased and maintained in this increased state for a predetermined duration; that is, the suspension is stretched for more than the predetermined duration. Here, the predetermined duration is predetermined, for example, determined to be greater than the duration during which the wheel suspension travel changes when the vehicle experiences a brief fluctuation while driving over an uneven road surface such as a pothole. Thus, according to embodiments of the present invention, the change in wheel suspension travel can be distinguished from the brief fluctuations experienced under bumpy road conditions.

[0019] In one embodiment, the driving assistance unit 20 includes a first detection module 21, a second detection module 22, a recognition module 23, and a decision module 24. It is understood that the naming of these modules is functional and not intended to limit their implementation or physical location. For example, these modules may be implemented on the same chip or circuit, or on different chips or circuits. Furthermore, some or all of these modules may be combined into one module, or further divided into multiple sub-modules.

[0020] The driver assistance unit 20 and its various modules can be implemented in hardware, software, or a combination of both. For the hardware implementation, it can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), data signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic units designed to perform their functions, or combinations thereof. For the software implementation, it can be implemented using microcode, program code, or code segments, and can also be stored in a machine-readable storage medium such as a storage component.

[0021] In one embodiment, the driver assistance unit 20 may be located in the vehicle's electronic control unit (ECU), or in the vehicle's body control unit (VCU), or in the vehicle's domain controller.

[0022] In one embodiment, some of the modules of the driving assistance unit 20 are located in one ECU of the vehicle, while other modules are located in another ECU or VCU of the vehicle.

[0023] In one embodiment, the driving assistance unit 20 is implemented including a memory and a processor. The memory contains instructions that, when executed by the processor, cause the processor to perform a driving assistance method according to an embodiment of the present invention.

[0024] The execution unit 30 is communicatively connected to the driving assistance unit 20 and is used to execute the driving assistance strategies decided by the driving assistance unit 20. The execution unit 30 may include, for example, a vehicle brake actuator for executing braking control decided by the driving assistance unit 20. The execution unit 30 may also include, for example, a vehicle drive actuator for executing drive control decided by the driving assistance unit 20. The execution unit 30 may also include, for example, an ECU or VCU electrically connected to the driving assistance unit 20 for executing the control scheme decided by the driving assistance unit 20, such as adjusting the response characteristics of the drive torque.

[0025] Figure 2 This is a flowchart of a vehicle driving assistance method 200 according to an embodiment of the present invention. Method 200 can be executed by the aforementioned system 100 or the aforementioned driving assistance unit 20. The specific implementation of method 200 will be described below using the driving assistance unit 20 executing method 200 as an example.

[0026] See Figure 2 In box 202, the first detection module 21 detects whether each wheel is a stable wheel or an unstable wheel based on the slip ratio of each wheel, so as to obtain the first detection result.

[0027] In one embodiment, the first detection module 21 acquires the slip ratio of each wheel from the sensor unit 10 and compares the slip ratio of each wheel with a slip ratio threshold. If the slip ratio of a wheel is greater than the slip ratio threshold, the wheel is identified as an unstable wheel, i.e., an unstable wheel is detected. If the slip ratio of a wheel is less than or equal to the slip ratio threshold, the wheel is identified as a stable wheel, i.e., a stable wheel is detected. Thus, a first detection result is obtained, including whether each wheel is a stable or unstable wheel. According to an embodiment of the present invention, the slip ratio threshold is predetermined and can be adjusted according to the real-time vehicle speed and the wheel's lateral and longitudinal adhesion characteristics. The present invention does not limit the specific value of the slip ratio threshold and its adjustment amount.

[0028] In block 204, the second detection module 22 detects whether the suspension of each wheel is in a compressed or extended state based on the suspension travel of each wheel, and detects the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle to obtain a second detection result. In general, the second detection module 22 performs two aspects of detection: one is the change in wheel suspension travel; the other is the vehicle's acceleration resistance. Specific embodiments of these two aspects of detection are described below.

[0029] In one embodiment, the second detection module 22 acquires the suspension travel of each wheel from the sensor unit 10 and compares the suspension travel of each wheel with a reference suspension travel. The reference suspension travel refers to the wheel suspension travel when the vehicle is parked on a level surface. If a wheel's suspension travel is less than the reference suspension travel, it is determined that the wheel's suspension is in a compressed state. If a wheel's suspension travel is greater than the reference suspension travel, it is determined that the wheel's suspension is in a stretched state. This yields a detection result that indicates whether each wheel's suspension is in a compressed or stretched state.

[0030] In one embodiment, the second detection module 22 compares the acceleration difference between the vehicle's actual acceleration and the calculated acceleration with a first threshold value for the acceleration difference to obtain a detection result that includes whether the acceleration difference is greater than the first threshold value. The vehicle's actual acceleration can be measured by the sensor unit 10. The vehicle's calculated acceleration is the theoretical acceleration calculated based on the vehicle's driving force and mass; for example, the vehicle should have acceleration calculated using a model. When the vehicle's actual acceleration is less than the calculated acceleration and the difference between them is greater than the acceleration threshold value, it means that the vehicle is at risk of acceleration being hindered.

[0031] In box 206, decision module 23 determines a driving assistance strategy based on the first detection result and the second detection result.

[0032] Specifically, when the first detection result is that all four wheels are unstable (i.e., all four wheels are slipping), and the second detection result is that at least one wheel suspension is in a compressed or stretched state (i.e., the suspension travel of one, two, three, or four wheel suspensions has changed relative to the suspension travel of the reference wheel, shortening or increasing); or when the first detection result is that all four wheels are unstable and the second detection result is that the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle is greater than a first threshold value for acceleration difference, the decision module 23 determines to execute the first driving assistance strategy.

[0033] If the first detection result is that at least one of the four wheels is a stabilizing wheel (i.e., the number of stabilizing wheels can be one, two, three, or four), and the second detection result is that at least one wheel suspension is in a stretched or compressed state (i.e., the suspension travel of at least one wheel has changed, shortened or increased, relative to the reference suspension travel); or if the first detection result is that at least one of the four wheels is a stabilizing wheel and the second detection result is that the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle is greater than a first threshold of acceleration difference, the decision module 23 determines to execute the second driving assistance strategy.

[0034] The first driver assistance strategy is described in detail below. The first driver assistance strategy includes one or more of the following. In other words, according to the first driver assistance strategy, any one or more of the following strategies can be executed, and when multiple strategies are executed, their execution order is not restricted.

[0035] (1) Reduce the ratio of the vehicle’s driving torque or driving force to the throttle opening; reduce the torque loading slope; and apply braking to the unstable wheel to limit the slippage of the unstable wheel.

[0036] "Reducing the ratio of vehicle driving torque or driving force to throttle opening" refers to modifying the ratio (i.e., the established correspondence or mapping) between throttle opening and vehicle driving torque or driving force so that the driving torque or driving force corresponding to the same throttle opening is reduced. For example, reducing the driving torque or driving force corresponding to each throttle opening by 10-20% means that at the same throttle opening, the driving torque or driving force will be adjusted to 80%-90% of its original level. Based on this operation, when the driver presses the accelerator pedal or the driving assistance system issues an accelerator command, the increase in driving torque or driving force will be reduced relative to their established mapping relationship.

[0037] "Reducing the torque loading slope" refers to slowing down the rate of torque increase relative to time or steering angle. By reducing the torque loading slope, the increase in torque within the same steering angle or time interval will be reduced, thus slowing the rate of torque increase. Based on this control, the vehicle's power output can be made smoother. This adjustment is particularly meaningful for electric vehicles because electric vehicle motors have the characteristic of instantaneous high torque output. By reducing the torque loading slope, this problem can be effectively solved, thereby ensuring vehicle safety and stability while responding to the driver's accelerator pedal input or the acceleration requests of the driving assistance system.

[0038] "Applying braking to the unstable wheel" includes applying braking force and / or applying a reverse driving force to the unstable wheel to suppress slippage of the unstable wheel. In one embodiment, braking is applied to the unstable wheel such that the amount of slippage of the unstable wheel is limited to a first predetermined range.

[0039] (2) When the wheel speed or acceleration of any wheel is greater than the corresponding threshold, brake is applied to the wheel so that the amount of slippage of the wheel is limited to a second predetermined range.

[0040] In one embodiment, when the wheel speed of any wheel exceeds a wheel speed threshold, braking force and / or reverse driving force are applied to that wheel to limit the wheel slippage within a second predetermined range. According to embodiments of the invention, the wheel speed threshold is predetermined and can be adjusted based on real-time vehicle speed and the wheel's lateral and longitudinal adhesion characteristics. The invention does not limit the specific values ​​of the wheel speed threshold or its adjustment amount.

[0041] In another embodiment, when the acceleration of any wheel exceeds a wheel acceleration threshold, braking force and / or reverse driving force are applied to that wheel to limit the wheel slippage within a second predetermined range. According to embodiments of the invention, the wheel acceleration threshold is predetermined and can be adjusted based on the actual wheel-end drive signal magnitude and wheel speed. The invention does not limit the specific value of the wheel acceleration threshold or its adjustment amount.

[0042] According to embodiments of the present invention, the first and second predetermined ranges for limiting the amount of vehicle slippage can be the same or different. Both ranges can be calculated based on real-vehicle test results and / or models. Moreover, these two ranges can be adjusted according to the needs of the vehicle user so that the vehicle behavior meets the user's expectations.

[0043] (3) When the vehicle is traveling uphill, the driving force of the vehicle is limited to be equal to or slightly greater than the component of the vehicle's weight along the direction parallel to the slope. "Slightly greater than" can be 100% to 110% of the component of the vehicle's weight along the direction parallel to the slope, or the sum of the component of the vehicle's weight along the direction parallel to the slope and a small redundancy. Based on this control, the drive wheels can have sufficient power to climb the slope and avoid excessive slippage (e.g., wheel spin) caused by excessive driving force.

[0044] (4) If the requested steering wheel angle is greater than a steering angle threshold, reduce the driving torque or driving force on the steering wheels. The steering wheel angle request can be issued by the driver (e.g., driver driving mode) or by a driver assistance system (e.g., automatic driving mode). Based on this operation, the lateral force (lateral grip of the tires) can be increased by reducing the longitudinal force (forward thrust) on the drive wheels, thereby ensuring that the vehicle's steering response can meet (match) the requested steering wheel angle.

[0045] (5) When the actual acceleration of the vehicle is less than the calculated acceleration and the difference between them is greater than the second threshold for acceleration difference, and the vehicle speed is less than the vehicle speed threshold, the decision module 24 predicts that the vehicle is experiencing acceleration obstruction or is about to experience acceleration obstruction. Here, the definition and implementation of calculated acceleration are the same as those described above, so the above description also applies here. The second threshold for acceleration difference is greater than the first threshold for acceleration difference described above, which means that the deviation between the actual acceleration and the calculated acceleration is greater than that in the case where the first threshold for acceleration difference is used. This situation means that a large driving force has been applied to the vehicle, but the vehicle speed is still very low. According to an embodiment of the present invention, both the second threshold for acceleration difference and the vehicle speed threshold are predetermined. Furthermore, these two thresholds are jointly determined through real vehicle testing and / or model calculation to jointly describe the conditions for predicting vehicle obstruction.

[0046] If a risk of traffic obstruction is anticipated, a warning can be issued to the driver via the vehicle's human-machine interface (not shown). The advantage of this approach is that by analyzing vehicle behavior, the risk of obstruction can be predicted and the driver alerted, allowing them to take appropriate action before the obstruction occurs.

[0047] If a risk of traffic obstruction is anticipated, the following strategy can be implemented: Control the vehicle to a stop, reverse a short distance, and then proceed through the current road segment at a controlled speed. The controlled speed and reversing distance can be determined as follows: Record the moment the vehicle stops, the first speed V1 at that position in the previous cycle, and the second speed V2 after reversing and then moving forward to reach that position. This second speed V2 is determined to be equal to the sum of the first speed V1 and a predetermined speed offset V_Off. Then, based on the second speed V2 and the road surface friction coefficient, calculate the minimum distance required to ensure the vehicle reaches the second speed V2 when reaching that position; this distance is taken as the reversing distance.

[0048] (6) When the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle is greater than a first threshold value for acceleration difference and the vehicle speed is greater than a vehicle speed threshold value (e.g., in a high-speed driving state), the slip ratio threshold value is adjusted in the direction of increase, for example, by increasing the slip ratio threshold value by a first slip ratio adjustment amount. According to an embodiment of the present invention, the first slip ratio adjustment amount can be predetermined and can be adjusted according to the real-time vehicle speed and the lateral and longitudinal adhesion characteristics of the wheel. The present invention does not limit the specific value of the first slip ratio adjustment amount. Through such adjustment, a larger amount of wheel slippage can be allowed within a certain range.

[0049] The second driver assistance strategy is described below. The second driver assistance strategy includes one or more of the following. In other words, according to the second driver assistance strategy, any one or more of the following strategies can be executed, and when multiple strategies are executed, their execution order is not restricted.

[0050] (1) Increase the ratio of the vehicle’s driving torque or driving force to the throttle opening and apply braking to the unstable wheel.

[0051] "Increasing the ratio of vehicle driving torque or driving force to throttle opening" refers to modifying the ratio (i.e., the established correspondence or mapping relationship) between throttle opening and vehicle driving torque or driving force so that the driving torque or driving force corresponding to the same throttle opening increases. For example, increasing the driving torque or driving force corresponding to each throttle opening by 10-20% means that at the same throttle opening, the driving torque or driving force will be adjusted to 110%-120% of the original level. Based on this operation, when the driver presses the accelerator pedal or the driving assistance system issues an accelerator command, the increase in driving torque or driving force will increase relative to their established mapping relationship.

[0052] "Applying braking force to the unstable wheel" includes applying braking force and / or applying reverse driving force to the unstable wheel to suppress wheel slippage. In one embodiment, braking is applied to the unstable wheel so that the amount of wheel slippage is limited to a third predetermined range. According to embodiments of the invention, this third predetermined range may be the same as or different from the first predetermined range described above. Similarly, the third predetermined range is calculated based on real vehicle test results and / or models, and can be adjusted according to the needs of the vehicle user to ensure that the vehicle behavior meets the user's expectations.

[0053] (2) When the difference between the actual driving torque and the target driving torque of the vehicle or the difference between the actual driving force and the target driving force is greater than the corresponding difference threshold, the unstable wheel is braked according to the predetermined correspondence between the driving torque or driving force and the braking force, for example, the braking force and / or reverse driving force are applied to the unstable wheel.

[0054] (3) If the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle is greater than a first threshold value for acceleration difference, the slip ratio threshold is adjusted in the direction of increase, for example, by increasing the slip ratio threshold by a second slip ratio adjustment amount. Similarly, the second slip ratio adjustment amount can be predetermined and can be adjusted according to the real-time vehicle speed and the lateral and longitudinal adhesion characteristics of the wheel. The present invention does not limit the specific value of the second slip ratio adjustment amount. Through such adjustment, a larger amount of wheel slippage can be allowed within a certain range. The second slip ratio adjustment amount can be equal to the first slip ratio adjustment amount, or the two slip ratio adjustment amounts can be unequal.

[0055] If the difference between the vehicle's actual driving torque and the target driving torque exceeds a torque difference threshold (e.g., the actual driving torque is too high relative to the target driving torque) or the difference between the actual driving force and the target driving force exceeds a driving force difference threshold (e.g., the actual driving force is too high relative to the target driving force), it means that the vehicle's actual driving performance / behavior does not closely follow the set target. In this situation, feedforward braking is used to address the problem in order to prevent tire damage due to excessive wheel slippage.

[0056] In one embodiment, a coordinate system is constructed to describe the predetermined relationship between driving torque (or driving force) and braking force, where the horizontal axis represents the magnitude of driving force or driving torque, and the vertical axis represents the magnitude of braking force. A curve is plotted on this coordinate system, representing the functional relationship (correspondence) between driving torque or driving force and the required braking force.

[0057] Furthermore, according to an embodiment of the present invention, after obtaining the first and second detection results, method 200 may proceed to block 208. In block 208, the identification module 23 identifies whether the type of road surface on which the vehicle is traveling is a first type or a second type based on the first and second detection results. Next, method 200 proceeds to block 210. In block 210, the decision module 24 determines whether to implement a first driving assistance strategy or a second driving assistance strategy based on the identified road surface type.

[0058] According to this embodiment, the road surface type is first identified based on a first detection result characterizing the response of wheel stability to road surface conditions and a second detection result characterizing the response of wheel suspension travel changes and vehicle acceleration resistance to road surface conditions. Then, the first or second driving assistance strategy is determined based on the identified road surface type.

[0059] Specifically, if the first detection result indicates that all four wheels are unstable, and the second detection result indicates that at least one wheel suspension is in a compressed or stretched state; or if the first detection result indicates that all four wheels are unstable, and the second detection result indicates that the acceleration difference between the vehicle's actual acceleration and calculated acceleration is greater than a first threshold value for acceleration difference, the identification result is that the type of road surface the vehicle is traveling on is Type 1. For Type 1 road surfaces, the decision module determines to execute a first driving assistance strategy. Type 1 road surfaces are soft road surfaces that will produce vertical deflection under vehicle load and may reduce vehicle passability. Type 1 road surfaces include, for example, deep snow or mud / sand roads.

[0060] If, in the first detection result, at least one of the four wheels is a stabilizing wheel, and in the second detection result, at least one wheel's suspension is under tension or compression; or, if in the first detection result, at least one of the four wheels is a stabilizing wheel, and in the second detection result, the difference between the vehicle's actual acceleration and its calculated acceleration is greater than a first threshold value for the acceleration difference, the road surface type is identified as Type II. For Type II road surfaces, the decision module determines to execute a second driving assistance strategy. Type II road surfaces are uneven, hard surfaces that may reduce vehicle passability. For example, a rocky road surface is a Type II road surface.

[0061] In embodiments of the present invention, a vehicle refers to a four-wheeled vehicle, that is, a vehicle comprising a left front wheel and a right front wheel coupled to the front axle of the vehicle, and a left rear wheel and a right rear wheel coupled to the rear axle of the vehicle.

[0062] In embodiments of the present invention, various thresholds or predetermined values ​​are employed. These thresholds are predetermined, for example, based on real-vehicle test results and / or models. The present invention does not limit their specific values. Moreover, these thresholds can also be customized for vehicle users (e.g., OEMs or vehicle drivers) based on their preferences, thereby ensuring that the vehicle's steering style meets the user's preferences. It should be understood that the customized thresholds to meet the user's preferences are determined while fully ensuring vehicle driving safety. Therefore, these customized thresholds should be understood as meeting the user's preferences to a certain extent without sacrificing vehicle safety.

[0063] According to embodiments of the present invention, a vehicle is also provided, which includes the aforementioned driving assistance unit. Therefore, the vehicle according to embodiments of the present invention possesses the aforementioned features and advantages.

[0064] According to an embodiment of the present invention, a machine-readable storage medium is also provided, which stores executable instructions that, when executed, cause one or more processors to perform the driving assistance method 200 as described above.

[0065] According to an embodiment of the present invention, a computer program product is also provided, which includes computer-executable instructions that, when executed, cause one or more processors to perform the driving assistance method 200 as described above.

[0066] It should be noted that all operations in the methods described above are merely exemplary, and this disclosure is not limited to any operation in the methods or the order of such operations, but should cover all other equivalent transformations under the same or similar concept.

[0067] It should be noted that a processor can be any combination of one or more of the following: a suitable central processing unit, CPU, multiprocessor, microcontroller, digital signal processor, DSP, application-specific integrated circuit, etc., capable of executing software instructions of a computer program stored in memory. Therefore, memory can be considered part of or constituting part of a computer program product. The processor can be configured to execute the computer program stored therein to cause the controller to perform the required steps.

[0068] It should be noted that software should be broadly considered as representing instructions, instruction sets, code, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, running threads, procedures, functions, etc. Software may reside on a computer-readable medium. Computer-readable media may include, for example, memory, which may be, for example, magnetic storage devices (e.g., hard disks, floppy disks, magnetic stripes), optical disks, smart cards, flash memory devices, random access memory (RAM), read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), registers, or removable disks. Although memory is shown as separate from the processor in several aspects set forth in this disclosure, memory may also reside within the processor (e.g., in caches or registers).

[0069] The above description is provided to enable any person skilled in the art to implement the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Therefore, the claims are not intended to be limited to the aspects shown herein. All structural and functional equivalents of the elements of the various aspects described herein, as known or forthcoming to those skilled in the art, are expressly incorporated herein by reference and are intended to be covered by the claims.

Claims

1. A driving assistance unit for a vehicle, comprising: The first detection module is configured to detect whether each wheel is a stable wheel or an unstable wheel based on the slip ratio of each wheel, so as to obtain the first detection result; The second detection module is configured to detect whether the suspension of each wheel is in a compressed or extended state based on the suspension travel of each wheel, and to detect the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle, so as to obtain the second detection result. as well as The decision-making module is configured to determine the driving assistance strategy based on the first detection result and the second detection result; Wherein, if the first detection result is that all four wheels are unstable and the second detection result is that at least one wheel suspension is in a compressed or stretched state; or if the first detection result is that all four wheels are unstable and the second detection result is that the acceleration difference is greater than a first threshold value, the driving assistance strategy is the first driving assistance strategy; and If the first detection result indicates that there is at least one stabilizing wheel and the second detection result indicates that at least one wheel suspension is in a stretched or compressed state; or if the first detection result indicates that there is at least one stabilizing wheel and the second detection result indicates that the acceleration difference is greater than a first threshold value of the acceleration difference, then the driving assistance strategy is the second driving assistance strategy.

2. The driving assistance unit as described in claim 1 further includes a recognition module configured to identify whether the road surface on which the vehicle is traveling is a first type of road surface or a second type of road surface based on the first and second detection results; wherein, The first test result is that all four wheels are unstable wheels and the second test result is that at least one wheel suspension is in a compressed or stretched state. Alternatively, if the first detection result is that all four wheels are unstable wheels and the second detection result is that the acceleration difference is greater than the first threshold of acceleration difference, the identification result is that the road surface on which the vehicle is driving is the first type of road surface, and the decision module determines the first driving assistance strategy. The first test result is that there is at least one stabilizing wheel and the second test result is that at least one wheel suspension is in a state of tension or compression; Alternatively, if the first detection result is that there is at least one stable wheel and the second detection result is that the acceleration difference is greater than the first threshold of acceleration difference, the identification result is that the road surface on which the vehicle is driving is the second type of road surface, and the decision module determines the second driving assistance strategy.

3. The driving assistance unit as described in claim 2, wherein, The first type of road surface is a soft road surface that will exhibit vertical deflection under vehicle loads and may reduce vehicle passability; and The second type of road surface is an uneven, hard surface that may reduce vehicle passability.

4. The driving assistance unit as described in claim 3, wherein, The first type of road surface is snow or muddy / sandy, and the second type of road surface is rocky.

5. The driving assistance unit as claimed in claim 1, wherein, The first detection module is configured as follows: When the slip ratio of a wheel exceeds a slip ratio threshold, the wheel is identified as an unstable wheel; and A wheel is identified as a stable wheel when its slip ratio is less than or equal to the slip ratio threshold.

6. The driving assistance unit as claimed in claim 1, wherein, The second detection module is configured as follows: When the suspension travel of a wheel is less than the suspension travel of a reference wheel and remains in this state for a predetermined duration, the wheel suspension is determined to be in a compressed state; and When the suspension travel of a wheel exceeds the suspension travel of the reference wheel and remains in this state for a predetermined duration, the wheel suspension is determined to be in a stretched state. The reference suspension travel refers to the wheel suspension travel when the vehicle is parked on a level surface.

7. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: - Reduce the ratio of the vehicle's driving torque or driving force to the throttle opening; - Reduce the torque loading slope; - Apply braking force to the unstable wheel so that the slippage of the unstable wheel is limited to a first predetermined range.

8. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: When the wheel speed or acceleration of any wheel exceeds a corresponding threshold, braking is applied to that wheel so that the amount of slippage of that wheel is limited to a second predetermined range.

9. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: When the vehicle is traveling uphill, the driving force of the vehicle is determined to be equal to or slightly greater than the component of the vehicle's weight along the direction parallel to the slope.

10. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: If the requested steering wheel angle is greater than the steering angle threshold, the driving torque or driving force on the steering wheel is reduced by a predetermined ratio.

11. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: If the difference between the vehicle's actual acceleration and the calculated acceleration is greater than the second threshold for acceleration difference and the vehicle speed is less than the vehicle speed threshold, execute one or both of the following strategies: - Anticipate the risk of vehicle obstruction and send a message to the driver warning of the risk; -Bring the vehicle to a complete stop, reverse a short distance, and then proceed through the current road section at a controlled speed. Wherein, the second threshold of acceleration difference is greater than the first threshold of acceleration difference.

12. The driving assistance unit as claimed in claim 1, wherein, First-level driver assistance strategies include: If the acceleration difference is greater than the first threshold for acceleration difference and the vehicle speed is greater than the vehicle speed threshold, the wheel slip ratio threshold is increased.

13. The driving assistance unit as claimed in claim 1, wherein, The second driver assistance strategy includes: Increase the ratio of the vehicle's driving torque or driving force to the throttle opening, and apply braking to the unstable wheel so that the slippage of the unstable wheel is limited to a first predetermined range.

14. The driving assistance unit as claimed in claim 1, wherein, The second driver assistance strategy includes: If the difference between the vehicle's actual driving torque and the target driving torque is greater than the torque difference threshold, or the difference between the actual driving force and the target driving force is greater than the driving force difference threshold, braking is applied to the unstable wheel according to the predetermined correspondence between the driving torque or driving force and the braking force.

15. The driving assistance unit as claimed in claim 1, wherein, The second driver assistance strategy includes: If the acceleration difference is greater than the first threshold value of the acceleration difference, the wheel slip ratio threshold value is increased.

16. A vehicle comprising a driving assistance unit as claimed in any one of claims 1-15.

17. A driving assistance method for a vehicle, comprising: The system detects whether each wheel is stable or unstable based on its wheel speed or slip ratio, in order to obtain the first detection result. The system detects whether the suspension of each wheel is in a compressed or extended state based on the suspension travel of each wheel, and detects the acceleration difference between the actual acceleration and the calculated acceleration of the vehicle to obtain a second detection result. The driving assistance strategy is determined based on the first and second test results; Wherein, if the first detection result is that all four wheels are unstable and the second detection result is that at least one wheel suspension is in a compressed or stretched state; or if the first detection result is that all four wheels are unstable and the second detection result is that the acceleration difference is greater than a first threshold value, the driving assistance strategy is the first driving assistance strategy; and If the first detection result indicates that there is at least one stabilizing wheel and the second detection result indicates that at least one wheel suspension is in a stretched or compressed state; or if the first detection result indicates that there is at least one stabilizing wheel and the second detection result indicates that the acceleration difference is greater than a first threshold value of the acceleration difference, then the driving assistance strategy is the second driving assistance strategy.

18. A computer program product comprising computer-executable instructions that, when executed, cause one or more processors to perform the driving assistance method of claim 17.

Images