Vehicle body descent speed calculation method and system, vehicle pedestrian protection system and method

Abstract

The present invention discloses a vehicle body descent speed calculation method and system, and a vehicle pedestrian protection system and method, comprising: obtaining a vertical component of the relative speed based on the horizontal distance from the leg collision point to the head collision point when a pedestrian collides with a vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative speed of the pedestrian and the vehicle at the time of collision; determining the vehicle body descent speed based on the vertical component; starting the vehicle's automatic deflation system to deflate the vehicle at the vehicle body descent speed; the present invention utilizes the active inflation and deflation system configured in the vehicle to reduce the body height and tire stiffness, thereby improving pedestrian protection performance while taking into account the vehicle design stiffness; compared with other high-cost solutions such as installing cushioning airbags and utilizing active engine covers, the present invention has the advantages of no additional cost and high integration.

Description

Technical Field

[0001] The present invention belongs to the technical field of pedestrian protection, and in particular relates to a vehicle body descent speed calculation method and system, and a vehicle pedestrian protection system and method. Background Art

[0002] The current vehicle pedestrian protection test requires that test points be marked on the hood, fenders, A-pillars, front windshield, etc., and then a human head model is used to impact each test point at a certain speed. The pedestrian protection performance is evaluated by obtaining the acceleration of the head. The pedestrian protection performance score will affect the vehicle's vehicle safety rating.

[0003] To meet pedestrian protection performance requirements, test points generally require limited stiffness and sufficient deformation space below the test points. Due to vehicle structure and styling, areas such as the hood latch, hood hinges, and A-pillars typically have relatively high stiffness, resulting in low test scores in these areas, which can pose significant head damage to pedestrians. This presents a current challenge in vehicle optimization. Summary of the Invention

[0004] In order to strike a balance between vehicle stiffness and vehicle safety rating, the present invention proposes a vehicle body descent speed calculation method and system, and a vehicle pedestrian protection system and method.

[0005] A vehicle body descent speed calculation system for achieving one of the objectives of the present invention comprises:

[0006] Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of collision; that is, the vertical downward component of the relative velocity perpendicular to the horizontal plane;

[0007] Vehicle body descending speed calculation unit: used to determine the descending speed of the vehicle body according to the vertical component of the relative speed.

[0008] Furthermore, in the vertical velocity calculation unit, the method for calculating the vertical component velocity of the relative velocity includes:

[0009] Obtaining, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when performing a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius;

[0010] Draw a tangent line of the circular motion through the head collision point, and draw a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle;

[0011] According to the included angle and the relative speed between the pedestrian and the vehicle at the time of collision, the vertical component of the relative speed is obtained.

[0012] Furthermore, the calculation method of the rotation angle includes:

[0013] θ=arcsin(L / H1)

[0014] Where: L and H1 are the horizontal distance from the pedestrian's leg impact point to the head impact point and the distance the pedestrian fits within the front envelope of the vehicle body, respectively.

[0015] Furthermore, the method for calculating the vertical component of the relative velocity includes:

[0016] V 头下 =V 头 ×cos(90°-θ)

[0017] V 头下 Indicates the vertical component of the relative velocity between the pedestrian and the vehicle at the time of collision;

[0018] V 头 Indicates the relative speed between the pedestrian and the vehicle at the time of collision;

[0019] θ represents the rotation angle.

[0020] Furthermore, the method for determining the descending speed of the vehicle body according to the vertical component velocity of the relative speed includes: the product of the vertical component velocity and a set weight is the descending speed of the vehicle body.

[0021] A method for calculating the vehicle body descent speed to achieve the second objective of the present invention includes:

[0022] The vertical component of the relative velocity is obtained based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision;

[0023] The descending speed of the vehicle body is determined according to the vertical component of the relative speed.

[0024] A vehicle pedestrian protection system for achieving the third objective of the present invention includes:

[0025] Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity, i.e., the vertical downward component perpendicular to the horizontal plane, based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision;

[0026] A vehicle body descending speed calculation unit is used to determine the descending speed of the vehicle body according to the vertical component of the relative speed;

[0027] Vehicle deflation unit: used to start the vehicle's automatic deflation system to deflate the vehicle at a speed at which the vehicle body descends.

[0028] The technical effect of the above system is: by deflating the vehicle, the vehicle body is lowered, which reduces the stiffness of the vehicle at the impact point, mitigates the collision contact impact, and has a good protective effect on pedestrians in the posture of hitting the vehicle head; experimental data confirms that through the simulation of the impact by the human head model, the use of the method described in the present invention can reduce the damage value from 1500 to 1400.

[0029] In the above system, a collision sensor is installed on the front bumper to sense the moment of collision of pedestrians; the height of pedestrians is obtained through an image collector, such as a camera, lidar, etc.

[0030] In the above system, the vertical speed calculation unit includes:

[0031] A first angle calculation unit is configured to calculate, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when the pedestrian makes a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius;

[0032] A second angle calculation unit is used to draw a tangent line of the circular motion through the head collision point and a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle;

[0033] A vertical component velocity calculation unit is used to obtain the vertical component velocity of the relative velocity according to the angle and the relative velocity between the pedestrian and the vehicle at the time of collision.

[0034] The product of the vertical component velocity and the set weight is the vehicle's descent speed, and the set weight is a positive number less than 1. The technical effect of this step is that when the vertical component velocity is significantly greater than the vehicle's descent speed, or when the vehicle's descent speed is significantly greater than the vertical component velocity, there will be no protective or buffering effect. Therefore, it is necessary to set a weight such that the vertical component velocity is slightly less than the vehicle's descent speed, thereby providing a reasonable buffer for pedestrians.

[0035] Furthermore, the set weight is a positive number less than 1, preferably in the range of [0.4, 0.6].

[0036] Furthermore, the method for calculating the rotation angle includes:

[0037] θ=arcsin(L / H1)

[0038] Where: L and H1 are the horizontal distance from the pedestrian's leg impact point to the head impact point and the distance the pedestrian fits within the front envelope of the vehicle body, respectively.

[0039] Furthermore, it also includes a vehicle speed judgment unit for judging the vehicle speed, which is used to judge whether the vehicle speed is within a set range; when the vehicle speed is within the set range, the vehicle is triggered to start the vehicle pedestrian protection system.

[0040] A vehicle pedestrian protection method for achieving the fourth objective of the present invention includes:

[0041] The vertical component of the relative velocity is obtained based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision; that is, the vertical downward component of the relative velocity perpendicular to the horizontal plane;

[0042] determining the descending speed of the vehicle body according to the vertical component velocity;

[0043] The automatic deflation system of the vehicle is started to deflate the vehicle at a speed at which the vehicle body descends.

[0044] Furthermore, the method for obtaining the vertical component of the relative velocity includes:

[0045] Obtaining, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when performing a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius;

[0046] Draw a tangent line of the circular motion through the head collision point, and draw a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle;

[0047] According to the angle and the relative speed between the pedestrian and the vehicle at the time of collision, the vertical component of the relative speed is obtained; the product of the vertical component of the speed and the set weight is the speed at which the vehicle body descends.

[0048] Furthermore, it also includes a vehicle speed judgment unit, which is used to judge whether the vehicle speed is within a set range. When the vehicle speed is within the set range, the vehicle is triggered to start the vehicle pedestrian protection method.

[0049] The beneficial effects of the present invention include:

[0050] 1. By accurately measuring and calculating key parameters during the collision process, the vehicle's descent speed at the moment of collision is effectively calculated, providing a score for subsequent vehicle safety performance evaluations;

[0051] 2. The present invention utilizes the vehicle's active inflation and deflation system to reduce body height and tire stiffness, thereby improving pedestrian protection while maintaining vehicle design stiffness. Compared with other high-cost solutions such as installing cushioning airbags and utilizing active engine covers, the present invention has the advantages of no additional cost and high integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a schematic flow chart of an embodiment of the method of the present invention;

[0053] Figure 2 This is one of the schematic diagrams of a vehicle colliding with a pedestrian;

[0054] Figure 3 This is the second diagram of a vehicle colliding with a pedestrian;

[0055] Figure 4 It is a schematic diagram of pedestrian protection without active deflation protection and with active deflation protection. DETAILED DESCRIPTION

[0056] The following detailed description is intended to explain the technical solutions of the present invention claims, so that those skilled in the art can understand the present claims. The scope of protection of the present invention is not limited to the specific implementation structures described below. Any implementation schemes created by those skilled in the art that incorporate the technical solutions of the present invention claims but differ from the following detailed descriptions are also within the scope of protection of the present invention.

[0057] In this invention, the automatic vehicle inflation and deflation technology primarily refers to the Central Inflation and Deflator (CIDC) system and the Central Tire Inflation System (CTIS). When a pedestrian collision is detected, the vehicle's automatic deflation system deflates the front wheels, rapidly reducing tire pressure and lowering the vehicle's height along with the pedestrian's head, creating a cushioning effect. Simultaneously, the tire's stiffness decreases, causing the pedestrian to impact the vehicle with a greater downward displacement. This ensures that the collision detection point meets pedestrian protection requirements and enhances vehicle safety.

[0058] Example 1

[0059] A vehicle pedestrian protection system, comprising:

[0060] Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of collision;

[0061] A vehicle body descending speed calculation unit is used to determine the descending speed of the vehicle body according to the vertical component of the relative speed;

[0062] Vehicle deflation unit: used to start the vehicle's automatic deflation system to deflate the vehicle at a speed at which the vehicle body descends.

[0063] like Figure 2 The figure shows a vehicle colliding with a pedestrian. The vehicle is equipped with a recognition system (including ADAS, etc.), and a collision sensor on the front bumper can actively identify pedestrians, their height, and whether they have collided with the vehicle. When a pedestrian is detected in front, the pedestrian's height H is obtained, and the collision points between the pedestrian's feet and the vehicle and the pedestrian's head are determined based on the vehicle's height. These are all existing technologies and will not be described in detail here.

[0064] The height from the foot impact point to the head impact point is H1;

[0065] Based on the vehicle's characteristics (shape and size), the horizontal distance from the leg impact point to the head impact point is known as L; L = the distance detected by the camera (pedestrian height - leg impact point) that fits within the front envelope of the vehicle body, with the head impact point located at the end of this fitting distance.

[0066] In the above system, the vertical speed calculation unit includes:

[0067] A first angle calculation unit is configured to calculate, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle θ of the pedestrian when the pedestrian makes a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius, i.e., sinθ=L / H1; θ=arcsin(L / H1);

[0068] The second angle calculation unit is used to make a tangent line of the circular motion through the head collision point and a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle, such as Figure 3 As shown, the head collision point is point A in the diagram, the tangent line is straight line L1 in the diagram, and the vertical line is straight line L2 perpendicular to the horizontal plane in the diagram;

[0069] A vertical component velocity calculation unit is used to obtain the vertical component velocity of the relative velocity according to the angle and the relative velocity between the pedestrian and the vehicle at the time of collision.

[0070] Furthermore, when the pedestrian's head collides with the vehicle, the relative speed between the pedestrian and the vehicle is V 头 , the vertical component of the relative velocity is V 头下 =V 头 ×cos(90°-θ).

[0071] V 车下 The speed at which the vehicle body lowers when the air is released.

[0072] When the pedestrian's downward velocity V 头下 Much greater than the speed V at which the vehicle body descends when the air is deflated 车下 When the vehicle is deflated, the speed at which the vehicle body descends is V 车下 Much greater than the vertical component of the relative velocity V of the pedestrian and the vehicle that collided with it 头下 When V 车下 =(0.4~0.6)×V 头下 When V 车下 V 头下 When the head collision is 0.4 to 0.6 times of the vehicle's acceleration, a better head protection effect can be achieved. The head collision with active deflation protection has a larger buffer space and buffer time, thereby reducing the pedestrian's head collision acceleration, such as Figure 4 As shown, the left picture is a schematic diagram without active deflation protection. Compared with the pedestrian protection schematic diagram with active deflation protection in the right picture, the head collision with active deflation protection has a larger buffer space and buffer time, thereby reducing the pedestrian's head collision acceleration.

[0073] In some embodiments, a vehicle speed determination unit is further included to determine whether the vehicle speed is within a set range. When the vehicle speed is within the set range, the vehicle is triggered to activate the vehicle pedestrian protection method. Because the deflation protection will not have a significant effect when the vehicle speed is too fast (for example, over 60 km / h) or too slow (for example, less than 20 km / h), in this embodiment, the vehicle pedestrian protection method or system is triggered when the vehicle speed is between 20 km / h and 60 km / h.

[0074] At the same time, by obtaining the vehicle's location, it can be determined whether it is in an area with pedestrians, such as village roads, urban roads, etc. By obtaining the vehicle's location, it can be determined whether the vehicle is in an area with pedestrians (communities, streets, villages) or an area without pedestrians (highways, closed roads, wild roads, etc.).

[0075] Because a vehicle's tire pressure is generally high and the tire rubber has certain damping properties, it's impossible to lower the vehicle immediately upon activation of the deflation system. Therefore, when the pedestrian's foot impacts the vehicle at time t0, the vehicle control system activates the automatic deflation system to reduce tire pressure. By the time the pedestrian's head impacts at time t1, the vehicle body has already reached a certain downward speed and the tires have been reduced in stiffness, thus lessening the impact of the pedestrian's collision.

[0076] Example 2

[0077] A vehicle pedestrian protection method, comprising:

[0078] like Figure 2As shown, according to the horizontal distance L from the leg collision point to the head collision point when the pedestrian collides with the vehicle, the distance H1 that the pedestrian fits within the front envelope of the vehicle body, and the relative speed V between the pedestrian and the vehicle at the time of collision, 头 Get the vertical component velocity V of the relative velocity 头下 ;

[0079] According to the vertical component velocity V 头下 Determine the speed V at which the vehicle body descends 车下 ;

[0080] Start the vehicle's automatic deflation system to lower the vehicle at the speed V 车下 Deflate the vehicle.

[0081] In some embodiments, the vertical component velocity V of the relative velocity is obtained 车下 Methods such as Figure 2 Shown, including:

[0082] According to the horizontal distance L and the distance H1 of the pedestrian adhered to the front of the vehicle body, the rotation angle θ of the pedestrian when performing a circular motion toward the vehicle with the leg collision point as the center, the vertical direction as the starting point, and the distance H1 of the pedestrian adhered to the front of the vehicle body as the radius is obtained;

[0083] like Figure 3 As shown, a tangent line L1 of the circular motion is drawn through the head collision point A, and a vertical line L2 is drawn through the head collision point A; the angle between the vertical line L2 and the tangent line L1 is obtained according to the rotation angle θ; the angle is 90°-θ;

[0084] According to the angle, the relative speed between the pedestrian and the vehicle at the time of collision, the vertical component velocity V of the relative speed is obtained. 头下 ;

[0085] The product of the vertical component velocity and the set weight is the descending speed of the vehicle body.

[0086] In some embodiments, the method for calculating the rotation angle includes:

[0087] θ=arcsin(L / H1)

[0088] Where: L and H1 are the horizontal distance from the pedestrian's leg impact point to the head impact point and the distance the pedestrian fits within the front envelope of the vehicle body, respectively.

[0089] In some embodiments, the vertical component of the relative velocity V 头下 The calculation methods include: V 头下 =V 头 ×cos(90°-θ).

[0090] In some embodiments, the vehicle body descends at a speed V 车下 The calculation methods include: V 车下 =V 头下 ×α; α is the set weight.

[0091] When the vertical velocity V 头下 Much greater than the speed V at which the vehicle body descends when the air is deflated 车下 When the vehicle is deflated, the speed at which the vehicle body descends is V 车下 Much larger than the pedestrian's downward velocity V 头下 When , it will not play a protective and buffering role, so the weight α is set to a positive number less than 1, and the preferred range is [0.4, 0.6].

[0092] In some embodiments, the vehicle speed is also judged. When the vehicle speed is within a set range, the vehicle is triggered to start the vehicle pedestrian protection method to maximize the effect of this method. Because when the vehicle speed is too fast or too slow, the deflation protection will not produce obvious effect. In this embodiment, the set range is [20km / h, 60km / h].

[0093] Example 3

[0094] A vehicle body descent speed calculation system, comprising:

[0095] Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of collision;

[0096] Vehicle body descending speed calculation unit: used to determine the descending speed of the vehicle body according to the vertical component of the relative speed.

[0097] In some embodiments, the vertical velocity calculation unit includes:

[0098] A first angle calculation unit is configured to calculate, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when the pedestrian makes a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius;

[0099] A second angle calculation unit is used to draw a tangent line of the circular motion through the head collision point and a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle;

[0100] A vertical component velocity calculation unit is used to obtain the vertical component velocity of the relative velocity according to the angle and the relative velocity between the pedestrian and the vehicle at the time of collision.

[0101] In some embodiments, the method for calculating the rotation angle includes:

[0102] θ=arcsin(L / H1)

[0103] Where: L and H1 are the horizontal distance from the pedestrian's leg impact point to the head impact point and the distance the pedestrian fits within the front envelope of the vehicle body, respectively.

[0104] In some embodiments, the method for calculating the vertical component of the relative velocity includes:

[0105] V 头下 =V 头 ×cos(90°-θ)

[0106] V 头下 Indicates the vertical component of the relative velocity between the pedestrian and the vehicle at the time of collision;

[0107] V 头 Indicates the relative speed between the pedestrian and the vehicle at the time of collision;

[0108] θ represents the rotation angle.

[0109] In some embodiments, the product of the vertical component velocity and the set weight is the descending speed of the vehicle body.

[0110] Example 4

[0111] A method for calculating a vehicle body descent speed, comprising:

[0112] The vertical component of the relative velocity is obtained based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision;

[0113] The descending speed of the vehicle body is determined according to the vertical component of the relative speed.

[0114] Example 5

[0115] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program. The computer program includes program instructions. When the program instructions are executed by a processor, the steps of the method of the present invention are implemented, which will not be described in detail here.

[0116] The computer-readable storage medium may be the data transmission device provided in any of the aforementioned embodiments or an internal storage unit of a computer device, such as a hard disk or memory of the computer device. The computer-readable storage medium may also be an external storage device of the computer device, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc., provided on the computer device.

[0117] Furthermore, the computer-readable storage medium may include both an internal storage unit of the computer device and an external storage device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium may also be used to temporarily store data to be output or that has been output.

[0118] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0119] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0120] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0121] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0122] Example 6

[0123] A computer program product includes a computer program / instruction, which implements any step of the vehicle pedestrian protection method when executed by a processor.

[0124] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A vehicle body descent speed calculation system, characterized in that: include: Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of collision; Vehicle body descending speed calculation unit: used to determine the descending speed of the vehicle body according to the vertical component of the relative speed.

2. A method for calculating the vehicle body descent speed, characterized in that: include: The vertical component of the relative velocity is obtained based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision; The descending speed of the vehicle body is determined according to the vertical component of the relative speed.

3. A vehicle pedestrian protection system, characterized in that: include: Vertical velocity calculation unit: used to calculate the vertical component of the relative velocity based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of collision; A vehicle body descending speed calculation unit is used to determine the descending speed of the vehicle body according to the vertical component of the relative speed; Vehicle deflation unit: used to start the vehicle's automatic deflation system to deflate the vehicle at a speed at which the vehicle body descends.

4. The vehicle pedestrian protection system according to claim 3, characterized in that: The vertical velocity calculation unit includes: A first angle calculation unit is configured to calculate, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when the pedestrian makes a circular motion from the upright face toward the vehicle body with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius; A second angle calculation unit is used to draw a tangent line of the circular motion through the head collision point and a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle; A vertical component velocity calculation unit is used to obtain the vertical component velocity of the relative velocity according to the angle and the relative velocity between the pedestrian and the vehicle at the time of collision.

5. The vehicle pedestrian protection system according to claim 4, characterized in that: The calculation method of the rotation angle includes: θ=arcsin(L / H1) Where: L and H1 are the horizontal distance from the pedestrian's leg impact point to the head impact point and the distance the pedestrian fits within the front envelope of the vehicle body, respectively.

6. The vehicle pedestrian protection system according to claim 4, characterized in that: The method for calculating the vertical component of the relative velocity includes: V 头下 =V 头 ×cos(90°- θ) V 头下 Indicates the vertical component of the relative velocity between the pedestrian and the vehicle at the time of collision; V 头 Indicates the relative speed between the pedestrian and the vehicle at the time of collision; θ represents the rotation angle.

7. The vehicle pedestrian protection system according to any one of claims 3 to 6, characterized in that: The product of the vertical component velocity and the set weight is the descending speed of the vehicle body.

8. The vehicle pedestrian protection system according to claim 3, wherein: It also includes a vehicle speed judgment unit for judging whether the vehicle speed is within a set range; when the vehicle speed is within the set range, the vehicle is triggered to start the vehicle pedestrian protection system.

9. A vehicle pedestrian protection method, characterized in that: include: The vertical component of the relative velocity is obtained based on the horizontal distance from the pedestrian's leg impact point to the head impact point when the pedestrian collides with the vehicle, the distance the pedestrian fits within the front envelope of the vehicle body, and the relative velocity between the pedestrian and the vehicle at the time of the collision; determining the descending speed of the vehicle body according to the vertical component velocity; The automatic deflation system of the vehicle is started to deflate the vehicle at a speed at which the vehicle body descends.

10. The vehicle pedestrian protection method according to claim 9, characterized in that: The method for obtaining the vertical component of the relative velocity includes: Obtaining, based on the horizontal distance and the distance the pedestrian fits within the front envelope of the vehicle body, a rotation angle of the pedestrian when performing a circular motion from an upright position toward the vehicle, with the leg collision point as the center and the distance the pedestrian fits within the front envelope of the vehicle body as the radius; Draw a tangent line of the circular motion through the head collision point, and draw a vertical line through the head collision point; and obtain the angle between the vertical line and the tangent line according to the rotation angle; According to the included angle and the relative speed between the pedestrian and the vehicle at the time of collision, the vertical component of the relative speed is obtained.

11. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the vehicle pedestrian protection method according to any one of claims 9 to 10 are implemented.

12. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, any step of the vehicle pedestrian protection method described in claims 9 to 10 is implemented.

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