Vehicle posture adjustment system and method for assisting automatic emergency braking

Abstract

The present invention discloses a vehicle posture adjustment system and method for assisting automatic emergency braking, comprising the following steps: obtaining collision information and obtaining an estimated collision time based on the collision information; selecting a safety strategy; obtaining an ideal collision posture based on the collision information and the safety strategy; and achieving an ideal motion state based on the estimated collision time and the ideal collision state. While the automatic emergency braking system is applying full braking, the present invention determines the ideal collision posture based on the selected safety strategy and the actual conditions between the vehicle and the collision object. The system then adjusts the vehicle's posture by manipulating the vehicle's steering system, colliding with the preceding vehicle in the safest possible posture, thereby enhancing protection for vehicle occupants.

Description

Technical Field

[0001] The present invention belongs to the field of safe driving, and in particular relates to a vehicle posture adjustment system and method for assisting automatic emergency braking. Background Art

[0002] With the development of intelligent driving technology today, some simple assisted driving functions have reached a relatively mature stage. For example, AEB has almost become a standard system for new car models.

[0003] Although the AEB system can perform timely and effective braking when two vehicles are about to collide, thus avoiding traffic accidents, for situations where collisions are urgent and unavoidable, the simple braking provided by AEB is still insufficient to protect the lives of people in the car.

[0004] According to relevant statistics, over 30% of traffic accidents occur in relatively small-angle collisions. Furthermore, during a collision, drivers, driven by a subconscious tendency to avoid risk, often manipulate the steering wheel to minimize the collision contact area. However, these maneuvers often increase the risk of injury to occupants. This is due to two reasons: First, current vehicle structural design and optimization prioritize protection against full frontal collisions, with the front anti-collision beam assembly and cabin longitudinal beams serving as primary load-bearing components. Small overlap or small-angle collisions are more likely to avoid these structures. Second, small-angle and small-overlap collisions can easily cause lateral swaying and other movements in the vehicle, and the placement of airbags and other features often provides less lateral protection than frontal protection. Crash results from the US SAE and IIHS, China C-NCAP, and China Insurance Research Institute (CIRI) consistently show that injuries to occupants in small- and medium-overlap and small-angle collisions are often greater than those in full-overlap head-on collisions.

[0005] How to reduce the damage caused by the vehicle's posture during a collision? Currently, there is no proper solution for the AEB system alone. Summary of the Invention

[0006] The purpose of the present invention is to provide a vehicle posture adjustment system and method for assisting automatic emergency braking to solve the problems existing in the above-mentioned prior art.

[0007] To achieve the above object, the present invention provides a vehicle posture adjustment method for assisting automatic emergency braking, comprising:

[0008] Obtain collision information, and obtain an estimated collision time based on the collision information; select a safety strategy; obtain an ideal collision posture based on the collision information and the safety strategy; and achieve an ideal motion state based on the estimated collision time and the ideal collision state.

[0009] Optionally, the collision information includes the position of the collision object, the speed of the collision object, the posture of the collision object, the collision position, the collision posture and the collision size.

[0010] Optionally, the safety strategy includes a full vehicle safety strategy and a specific position safety strategy, wherein a 100% overlapping frontal collision strategy is used as the full vehicle safety strategy, and a strategy of maximizing the distance between a specific position and the collision position is used as the specific position safety strategy.

[0011] Optionally, the process of obtaining the ideal collision posture includes: obtaining the ideal posture angle and ideal offset based on the selected safety strategy and collision information, obtaining the current speed of the car, and obtaining the ideal yaw angular velocity based on the ideal posture angle, ideal offset, current speed and the expected collision time.

[0012] The present invention also provides a vehicle posture adjustment system for assisting automatic emergency braking, which is characterized by comprising:

[0013] Perception module, decision module, control module;

[0014] The perception module is used to perceive the environment and detect collision targets;

[0015] The decision module is used to determine the ideal motion state of the vehicle;

[0016] The control module controls the vehicle steering system based on the ideal motion state of the vehicle to achieve the ideal motion state.

[0017] Optionally, the perception module obtains environmental information based on a perception system sensor, wherein the environmental information includes a position of the car relative to the collision object, a speed of the collision object, and a posture of the collision object.

[0018] Optionally, prediction information is calculated and acquired based on the environmental information, wherein the prediction information includes a collision position, a collision posture, and a collision size.

[0019] Optionally, the decision module obtains a collision target based on a safety strategy, and obtains an ideal collision state based on the collision target, the environmental information and the prediction information, wherein the safety strategy includes a full-vehicle safety strategy and a specific location safety strategy.

[0020] The technical effects of the present invention are:

[0021] While the automatic emergency braking system is applying full braking, it determines the ideal collision posture based on the selected safety strategy and the actual conditions of the car and the collision object, and adjusts the car's posture by manipulating the car's steering system to ensure that the ideal posture is achieved or close to it when a collision occurs, thereby improving the protection of the driver and passengers in the car. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0023] Figure 1 Schematic diagram of the structure of a vehicle posture adjustment system for assisting automatic emergency braking in an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a specific application of a system in an embodiment of the present invention;

[0025] Figure 3 Schematic diagram of the decision-making strategy in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0028] Example 1

[0029] This embodiment discloses an auxiliary posture adjustment technology based on AEB, which reduces the damage caused by the collision to the occupants of the vehicle by adjusting the posture of the rear vehicle when it collides with the front vehicle, and can realize the function of prioritizing the protection of occupants in specific positions during the collision.

[0030] The AEB system generally operates in two phases: warning and braking. Braking is further divided into two stages: partial braking and full braking. Partial braking means the likelihood of a collision is minimal and can be avoided simply by reducing vehicle speed. Full braking, on the other hand, means the likelihood of a collision is high or even unavoidable, requiring full braking to avoid or mitigate the impact and protect occupants as much as possible.

[0031] From the perspective of objectively reducing collision risk, adopting a reasonable collision angle and coverage is beneficial. From the perspective of subjectively protecting specific occupants (such as children, VIPs, etc.), the vehicle should also be positioned appropriately for collisions. This invention aims to automatically control the vehicle's steering system during the AEB full braking phase, thereby adjusting the vehicle's posture and improving collision safety for occupants.

[0032] This embodiment provides a vehicle posture adjustment method for assisting automatic emergency braking, including: obtaining collision information, and obtaining an estimated collision time based on the collision information; selecting a safety strategy; obtaining an ideal collision posture based on the collision information and the safety strategy; and achieving an ideal motion state based on the estimated collision time and the ideal collision state.

[0033] Optionally, the collision information includes the position of the collision object, the speed of the collision object, the posture of the collision object, the collision position, the collision posture, and the collision size.

[0034] Optionally, the safety strategy includes a full vehicle safety strategy and a specific location safety strategy, wherein a strategy of 100% overlapping frontal collision is used as the full vehicle safety strategy, and a strategy of maximizing the distance from the collision position at a specific location is used as the specific location safety strategy.

[0035] Optionally, the process of obtaining the ideal collision posture includes: obtaining the ideal posture angle and ideal offset based on the selected safety strategy and collision information, obtaining the current speed of the vehicle, and obtaining the ideal yaw angular velocity based on the ideal posture angle, ideal offset, current speed and expected collision time.

[0036] This embodiment further provides a vehicle posture adjustment system for assisting automatic emergency braking, which is characterized by comprising:

[0037] Perception module, decision module, control module;

[0038] The perception module is used to perceive the environment and detect collision targets;

[0039] The decision module is used to determine the ideal motion state of the vehicle;

[0040] The control module controls the vehicle steering system based on the ideal motion state of the vehicle to achieve the ideal motion state.

[0041] Optionally, the perception module obtains environmental information based on the perception system sensor, wherein the environmental information includes the position of the car relative to the collision object, the speed of the collision object, and the posture of the collision object.

[0042] Optionally, prediction information is obtained based on environmental information calculation, where the prediction information includes collision position, collision posture, and collision size.

[0043] Optionally, the decision module obtains a collision target based on a safety strategy, and obtains an ideal collision state based on the collision target, environmental information, and prediction information. The safety strategy includes a full-vehicle safety strategy and a specific location safety strategy.

[0044] Example 2

[0045] like Figure 1-3As shown, this embodiment provides a vehicle posture adjustment system and method for assisting automatic emergency braking, including:

[0046] The system consists of three parts: perception module, decision module and control module. Figure 1 shown.

[0047] The perception module not only senses the relative position and speed of the vehicle to the object that is about to collide, but also needs to provide the size and posture of the collision plane to realize the function of this system. The present invention recommends using laser scanning radar as the perception system sensor.

[0048] The decision-making module employs two strategies: The first is designed to improve the overall vehicle collision safety. Standardized automotive crash tests show that full-coverage head-on collisions are safer than small-coverage head-on collisions and small-angle collisions. Therefore, this strategy compares the position, size, and posture of the intended contact planes of the collision targets to determine the ideal collision posture for the vehicle, aiming for a 100% full-coverage head-on collision. The second strategy aims to improve the collision safety of a specific location within the vehicle (such as the passenger seat or the left or right rear seat). The ideal collision posture is determined by maximizing the distance between that location and the impact point during a collision.

[0049] like Figure 3 As shown in the figure, according to the two different decision strategies, the corresponding ideal attitude angle θ and ideal offset L can be estimated respectively. At the same time, the current vehicle speed V and the collision time t determined by the AEB system are obtained from the system. TTD , the vehicle's yaw rate r can be calculated using the following formula. Since the control time is very short, the smaller the yaw rate, the easier it is to achieve. Therefore, within the range of the Bernoulli coefficient, the minimum yaw rate is selected as the target motion.

[0050]

[0051] in:

[0052] r is the ideal yaw rate; θ is the longitudinal angle increment of the ideal attitude of the vehicle; L is the lateral distance increment of the ideal position of the vehicle; V is the current speed of the vehicle; t TTD is the collision time of AEB decision; p is the binary optimization Bernoulli coefficient.

[0053] The control module compares the time to collision (TTC) determined by the AEB system with the ideal collision posture of the vehicle output by the decision module, determines the steering wheel angle, speed and steering torque, and submits them to the vehicle's power steering system (EPS) for execution.

[0054] The vehicle lateral dynamics transfer function can be identified through vehicle standard field test data:

[0055]

[0056] in:

[0057] δ SW - steering wheel angle;

[0058] G ay ——Yaw angular velocity steady-state gain;

[0059] T ny1 , T ny2 , T dy1 , T dy2 ,…——time constant.

[0060] According to the above formula, the ideal yaw angular velocity corresponding to the steering wheel angle can be obtained for vehicle steering system control.

[0061] The above description is merely a preferred embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for adjusting the vehicle posture to assist automatic emergency braking, characterized in that: The following steps are involved: Obtain collision information, and obtain an estimated collision time based on the collision information; Select safety strategy; obtain ideal collision posture based on collision information and safety strategy; Achieve an ideal motion state based on the expected collision time and the ideal collision state; The collision information includes the position of the collision object, the speed of the collision object, the posture of the collision object, the collision position, the collision posture and the collision size; The safety strategy includes a full vehicle safety strategy and a specific position safety strategy, wherein the full vehicle safety strategy is a strategy of 100% overlap frontal collision, and the specific position safety strategy is a strategy of maximizing the distance from the collision position. The process of obtaining the ideal collision posture includes: obtaining an ideal posture angle and an ideal offset based on the selected safety strategy and collision information, obtaining a current vehicle speed, and obtaining an ideal yaw rate based on the ideal posture angle, the ideal offset, the current vehicle speed, and the estimated collision time; The calculation formula is as follows: Among them, r is the ideal yaw rate, θ is the longitudinal angle increment of the ideal attitude of the vehicle, L is the lateral distance increment of the ideal position of the vehicle, V is the current speed of the vehicle, t TTD is the collision time of AEB decision, p is the binary optimization Bernoulli coefficient; The vehicle posture adjustment method for assisting automatic emergency braking automatically controls the vehicle steering system during the full braking phase of the automatic emergency braking system to adjust the vehicle posture and improve the collision safety of the vehicle occupants. The vehicle posture adjustment method for assisting automatic emergency braking compares the collision time determined by the automatic emergency braking system with the ideal collision posture, determines the steering wheel angle, speed and steering torque, and submits them to the vehicle power steering system for execution.

2. A vehicle posture adjustment system for assisting automatic emergency braking that implements the vehicle posture adjustment method for assisting automatic emergency braking according to claim 1, characterized in that: include: Perception module, decision module, control module; The perception module is used to perceive the environment and detect collision targets; The decision module is used to determine the ideal motion state of the vehicle; The control module controls the vehicle steering system based on the ideal motion state of the vehicle to achieve the ideal motion state.

3. The vehicle posture adjustment system for assisting automatic emergency braking according to claim 2, characterized in that: The perception module acquires environmental information based on a perception system sensor, wherein the environmental information includes a position of the vehicle relative to a collision object, a speed of the collision object, and a posture of the collision object.

4. The vehicle posture adjustment system for assisting automatic emergency braking according to claim 3, characterized in that: Prediction information is calculated and acquired based on the environmental information, wherein the prediction information includes a collision position, a collision posture, a collision size, and a collision time.

5. The vehicle posture adjustment system for assisting automatic emergency braking according to claim 4, characterized in that: The decision module obtains a collision target based on a safety strategy, and obtains an ideal collision state based on the collision target, the environmental information, and the prediction information. The safety strategy includes a full-vehicle safety strategy and a specific location safety strategy.

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