CN109591754B - Method for protecting human-ground collision damage in human-ground collision accident - Google Patents

Method for protecting human-ground collision damage in human-ground collision accident Download PDF

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CN109591754B
CN109591754B CN201910010617.4A CN201910010617A CN109591754B CN 109591754 B CN109591754 B CN 109591754B CN 201910010617 A CN201910010617 A CN 201910010617A CN 109591754 B CN109591754 B CN 109591754B
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vehicle
human body
human
chest
ground
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CN109591754A (en
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邹铁方
何枫林
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Changsha University of Science and Technology
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60RVEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R21/00Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
    • B60R21/34Protecting non-occupants of a vehicle, e.g. pedestrians
    • B60R21/36Protecting non-occupants of a vehicle, e.g. pedestrians using airbags
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60RVEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R21/00Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
    • B60R21/34Protecting non-occupants of a vehicle, e.g. pedestrians
    • B60R21/38Protecting non-occupants of a vehicle, e.g. pedestrians using means for lifting bonnets

Abstract

Aiming at the existing research results, the human-ground collision injury is protected only by preventing the separation of a human body and a vehicle, and the human-ground collision injury is protected while the human body is allowed to fall to the ground by moving the vehicle and assisting with a vehicle-mounted safety device, wherein the vehicle-mounted safety device comprises a liftable engine cover and an air bag installed in a front bumper. After the accident happens, the vehicle is kept to be completely braked until t1 moment when the head of the human body collides with the vehicle for the first time; then controlling the speed of the vehicle to enable the rear edge of the vehicle engine cover and the chest of the human body to keep a certain distance d in the vehicle running direction and move forwards together; after t1, after the chest of the human body is detected to be in contact with the engine cover, adjusting the inclination angle of the engine cover according to the posture of the human body and starting to completely brake the vehicle again; and when the human body is detected to be about to fall to the ground, the external safety air bag is detonated and the vehicle is kept to be completely braked until the vehicle is static. The invention realizes the protection of the collision and the damage to the ground from three levels of vehicle body energy absorption, landing posture change and safety air bag energy absorption.

Description

Method for protecting human-ground collision damage in human-ground collision accident
Technical Field
The invention relates to the field of pedestrian protection, in particular to a method for protecting human-ground collision damage in a human-ground collision accident.
Background
Intellectualization has become a development trend of future technologies. For future automobiles, whether the automobiles are automatically driven or intelligent automobiles, the automobiles are provided with a large number of sensors to sense the environment outside the automobile so as to drive the automobile safely, comfortably and efficiently. However, considering the complexity of traffic, it is difficult to consider that the traffic accident of the future automobile never occurs at present under the cognitive level. In all accident types, the accident caused by the collision of the person and the vehicle is closely related to the trip of each person and is the fatal injury of the weak person caused by the strong person, and the accident naturally becomes the focus of attention. Therefore, how to reduce the human body injury in the accidents becomes a research hotspot.
Human injury in a vehicle occupant collision event results from a first impact with the vehicle followed by a second impact with the ground. Many studies have shown that while vehicle impacts are generally more severe, the damage caused by ground impacts is by no means negligible, especially at low speeds. Research shows that the total injury of the human body can be reduced 2/3 if the damage caused by the ground impact can be avoided at the time of less than 40 km/h. Human injury protection has therefore become a focus of research in recent years.
However, most of the researches concern the damage mechanism of the human body, and people find that the collision speed, the pedestrian speed, the gait, the height, the final landing posture and the vertical landing speed have obvious influence on the collision damage of the human body through the researches, but the researches on the specific human body damage protection method are few. Solutions for protecting the ground from injury are found in only a few documents, one of which is to prevent the ground from falling by arranging an air bag at the vehicle head, as in patent CN 107690399 a, "a pedestrian safety protection method and apparatus for vehicles"; in the second place, the hood is covered with a viscous liquid to stick the body to the ground, as disclosed in U.S. Pat. No. 4, 9,340,178, 1, "ADHESIVE VEHICLE FRONT FOR MITITITION OF SECONDARY PEDESTRAN IMPACT". The starting point of the schemes is that the human body cannot fall to the ground after the human body and the vehicle collide. At present, the better understood solution is that the human body finally needs to leave the vehicle and fall to the ground after the collision happens, and after all, the human body is in worry with the fast running automobile.
It is noted that the human landing posture, which can be changed by a moving vehicle, has been found to be significantly related to human collision injuries. Considering that the automobile has enough capacity to monitor the motion posture of the human body in real time in the future, the injury caused by human collision can be better protected by moving the automobile and assisting with vehicle-mounted safety equipment.
Disclosure of Invention
Aiming at the existing research results, the invention provides the method for protecting the human-ground collision damage by only preventing the separation of the human body and the vehicle, and provides the method for protecting the human-ground collision damage while allowing the human body to fall on the ground by moving the vehicle and assisting with a vehicle-mounted safety device, wherein the vehicle-mounted safety device comprises a liftable engine cover and an air bag arranged in a front bumper, and the implementation steps of the invention are as follows:
s1: after the accident happens, the vehicle is kept in a complete braking state until t1 moment when the head of the human body collides with the vehicle for the first time;
s2: after t1, controlling the speed of the vehicle to make the rear edge of the engine cover of the vehicle keep a certain distance d with the chest of the human body in the driving direction of the vehicle and move forwards together;
s3: after t1, after the chest of the human body is detected to be in contact with the engine cover, adjusting the inclination angle of the engine cover according to the posture of the human body and starting to completely brake the vehicle again;
s4: and when the human body is detected to be about to fall to the ground, the external safety air bag is detonated, and the full braking condition is kept until the vehicle is static.
When a vehicle accident occurs, the invention requires that the vehicle maintain a full braking condition until time t1 when the first impact of the pedestrian's head with the vehicle is detected; then, the rear edge of a vehicle engine cover and the chest of a human body keep a certain distance d in the vehicle running direction by controlling the running speed of the vehicle and move forwards together; t1, when the chest of the human body is detected to be contacted with the engine cover, adjusting the inclination angle of the engine cover according to the posture of the human body and starting to completely brake the vehicle again so as to ensure that the human body is separated from the vehicle body at a proper angle and slides to the ground; and when the human body is detected to be about to fall to the ground, the safety air bag outside the vehicle is detonated, and the full braking condition is kept until the vehicle is static, so that the human collision injury is prevented.
Preferably, t1 in step S1 is the time when the head of the human body collides with the vehicle for the first time. The vehicle is kept to be completely braked before the time t1, so that the impact speed of the head of the human body and the vehicle can be ensured to be unchanged, and the human body damage caused by the impact of the vehicle body is ensured not to be changed in the whole control process.
Preferably, in step S2, too large a distance d may make the hood inaccessible to a dropped person. And too small, especially negative d can make the human body fall windshield or even the roof go, and people's car interaction time overlength this moment not only can increase the human risk of injury of vehicle, and more importantly human body can obtain more kinetic energy from the automobile body to increase the speed of striking with ground, and then increase the damage risk that ground caused. To this end, d will be determined by the following rule: when the vehicle speed is lower than 25km/h, the distance d between the rear edge of the vehicle engine hood and the human body is the distance from the chest of the human body to the rear edge of the engine hood at the moment t 1; when the vehicle speed is higher than 25km/h and lower than 35km/h, d is the distance between the chest of the human body and the rear edge of the engine hood is reduced by 0.2 meter at the time of t 1; when the vehicle speed is higher than 35km/h, the distance from the chest of the human body to the rear edge of the engine hood is reduced by 0.4 m at the time of t 1; all calculations were replaced by 0 if the resulting value was negative. The distance calculation method can ensure that the vehicle is not accelerated or is accelerated as little as possible in the control process, and the vehicle is only decelerated or driven at a constant speed.
Preferably, the vehicle speed in step S2 is calculated by the following method:
assuming that the distance between the rear edge of the engine cover of the vehicle and the chest position of the human body at a certain time is d0, the running speed of the chest of the human body detected by the vehicle in the x direction is v20, and the distance is required to be adjusted to d within the delta t time, the running speed v of the vehicle within the delta t time is d
Figure GDA0002902371540000031
Preferably, the chest-hood contact is used as a judgment index in step S3, so that the acceleration of the vehicle, the increase of the kinetic energy of the human body and the increase of the human collision speed in the low-speed collision accident to reach the constraint condition of the distance d in step S2 can be further avoided. Under the low-speed impact, when the distance between the rear edge of the engine hood and the chest of the human body is larger than d, the chest of the human body is already contacted with the engine hood, the step S2 is not required to be continued, the step S3 can be directly started, and further the situation that the human body obtains more kinetic energy from the vehicle body due to the fact that the vehicle is accelerated is avoided.
Preferably, if the chest-head direction of the human body is consistent with the advancing direction of the vehicle in step S3, it indicates that the human body will land on the ground first if the vehicle is braked, so that the front edge of the engine cover needs to be lifted to make the inclination angle of the engine cover 0 °, and then the vehicle is completely braked to separate the human body from the vehicle, and the human body falls to the ground in a horizontal throwing manner. Since the human body is thrown horizontally after leaving the vehicle, the human body moves in a free falling body without initial speed in the vertical direction, which can obviously reduce the landing speed of the human body in the vertical direction. While studies have shown that human impact damage is significantly related to vertical impact velocity, a reduction in vertical velocity can reduce damage.
Preferably, if the chest-head direction of the human body is opposite to the driving direction of the vehicle, it indicates that the lower limbs, buttocks, etc. of the human body land before the head in this case in step S3. At this time, the inclination angle of the engine hood does not need to be changed, and the vehicle can be completely braked to separate people from the vehicle, so that the human body can sit on the ground in a sliding posture. Because the human body freely slides along the engine hood when finally leaving the vehicle, the human body can be seated to the ground in a posture similar to a sitting posture, and the collision energy can be absorbed by the lower limbs, the buttocks and other parts of the human body, so that the collision damage of the human body can be obviously reduced when the human body falls to the ground.
Preferably, the detection of the human body falling to the ground in step S4 indicates a time when the height of one of the head, chest or buttocks of the human body is lower than the height of the front edge of the hood. The air bag is ignited at this time, so that the air bag can be prevented from impacting a human body, and the situation that the air bag is ignited too early to hinder the movement of the vehicle can be avoided.
Preferably, in step S4, the external airbag is installed in the front bumper of the vehicle, the squib is connected to the center console of the vehicle, and the airbag has the same width as the vehicle, the same height as the lower edge of the front bumper, and the length of 1.5 m.
Compared with the prior art, the technical scheme of the invention has the beneficial effects that: the vehicle is moved to make the vehicle contact with a human body before falling to the ground so as to absorb part of the energy of falling of the human body, meanwhile, the inclination angle of an engine cover is changed so as to change the falling posture of the human body, further reduce the risk of collision damage of the human ground, and finally, the vehicle-mounted safety airbag cushions the first contact of the human ground, so that the protection of the collision damage of the human ground is realized from three layers of vehicle body energy absorption, falling posture change and safety airbag energy absorption.
Drawings
FIG. 1 is a flow chart of the method of the invention.
Figure 2 is a front view of the airbag after detonation.
Figure 3 is a side view of the airbag after detonation.
Fig. 4 is a schematic view of the movement process of the vehicle and human body after an accident in embodiment 1.
Wherein corresponding reference numerals in the figures are: 1-vehicle front bumper, 2-safety airbag, 3-width of safety airbag after detonation, 4-height of safety airbag after detonation, and 5-length of safety airbag after detonation.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent;
the technical solution of the invention is further explained with reference to the drawings and the embodiments.
Example 1
As shown in fig. 4, which is a schematic diagram of the movement process of the vehicle and the human body after the accident, at time t0, after the collision accident occurs, the vehicle is completely braked until time t1 when the head of the human body collides with the vehicle for the first time; then the human body is thrown out, and the vehicle keeps driving forwards together with the human body at a distance d; when t2, the chest-head direction of the human body is detected to be consistent with the vehicle motion method after the chest of the human body is detected to be contacted with the engine cover, so that the front edge of the engine cover is lifted to enable the inclination angle to be 0; the detection of the imminent falling of the body to the ground at time t4 detonates the airbag and then brakes fully until the vehicle is stationary.
As shown in figures 2 and 3, the front view and the side view of the airbag after detonation are respectively shown, the width of the airbag after detonation is the same as that of a vehicle, the height of the airbag is the same as that of the lower edge of a bumper, and the length of the airbag after detonation is 1.5 meters.
As shown in FIG. 1, the invention provides a method for protecting a human-ground collision injury in a human-ground collision accident, which is realized by the following steps:
s1: after the accident occurs, the vehicle is kept in a full braking state until the t1 moment when the head of the human body collides with the vehicle for the first time.
S2: after time t1, the vehicle speed is controlled so that the rear edge of the vehicle hood and the chest of the human body keep a certain distance d in the vehicle driving direction and move forward together.
The method for calculating the value of the distance d between the rear edge of the vehicle engine cover and the human body comprises the following steps: when the vehicle speed is lower than 25km/h, the value d is the distance from the chest of the human body to the rear edge of the engine hood at the time t 1; when the vehicle speed is higher than 25km/h and lower than 35km/h, the distance from the chest of the human body to the rear edge of the engine hood is reduced by 0.2 m at the time t 1; when the vehicle speed is higher than 35km/h, the distance from the chest of the human body to the rear edge of the engine hood is reduced by 0.4 m at the time of t 1; all calculations were replaced by 0 if the resulting value was negative.
The vehicle speed is obtained by calculating the following method: assuming that the distance between the rear edge of the engine cover of the vehicle and the chest position of the human body at a certain time is d0, the running speed of the chest of the human body detected by the vehicle in the x direction is v20, and the distance is required to be adjusted to d within the delta t time, the running speed v of the vehicle within the delta t time is d
Figure GDA0002902371540000051
S3: and after the chest of the human body is detected to be contacted with the engine cover, the inclination angle of the engine cover is adjusted according to the posture of the human body, and the vehicle starts to be completely braked again.
In this embodiment, at time t2, the chest of the human body contacts the engine cover, and the chest-head direction of the human body is detected to be consistent with the vehicle running direction, which indicates that the head of the human body collides with the ground first, so that the human body is thrown out horizontally by adjusting the inclination angle of the engine cover to 0 °.
S4: and when the human body is detected to be about to fall to the ground, the external safety air bag is detonated, and the full braking condition is kept until the vehicle is static.
At time t4, the airbag is detonated when the person's head is below the hood leading height, and then full braking is maintained until time t5 when the vehicle is stationary.
The invention provides a method for protecting ground collision damage in a vehicle-to-ground collision accident, which comprises the steps of moving a vehicle to enable the vehicle to be in contact with a human body before falling to the ground so as to absorb part of falling energy of the human body, changing the falling posture of the human body by changing the inclination angle of an engine cover so as to further reduce the risk of ground collision damage, and finally buffering the ground first contact through a vehicle-mounted safety airbag so as to realize the protection of the ground collision damage from three layers of vehicle body energy absorption, falling posture change and safety airbag energy absorption.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the described invention shall be included in the protection scope of the claims of the invention.

Claims (6)

1. A method of protecting a human-to-ground collision injury in a human-to-ground collision accident, characterized by: the vehicle is moved and assisted by vehicle-mounted safety equipment, so that a human body is allowed to fall on the ground and the human body is protected from collision and damage, the vehicle-mounted safety equipment comprises a liftable engine cover and an air bag arranged in a front bumper, and the specific implementation steps are as follows:
s1: after the accident happens, the vehicle is kept in a complete braking state until t1 moment when the head of the human body collides with the vehicle for the first time;
s2: after t1, controlling the speed of the vehicle to make the rear edge of the engine cover of the vehicle keep a certain distance d with the chest of the human body in the driving direction of the vehicle and move forwards together;
s3: after t1, after the chest of the human body is detected to be in contact with the engine cover, adjusting the inclination angle of the engine cover according to the posture of the human body and starting to completely brake the vehicle again;
s4: and when the human body is detected to be about to fall to the ground, the external safety air bag is detonated, and the full braking condition is kept until the vehicle is static.
2. A method of protecting a human impact injury in the event of a human impact event according to claim 1 wherein: in step S2, d is determined by the following rule:
when the vehicle speed is lower than 25km/h, d is the distance from the chest of the human body to the rear edge of the engine hood at the time of t 1; when the vehicle speed is higher than 25km/h and lower than 35km/h, d is the distance between the chest of the human body and the rear edge of the engine hood is reduced by 0.2 meter at the time of t 1; when the vehicle speed is higher than 35km/h, the distance from the chest of the human body to the rear edge of the engine hood is reduced by 0.4 m at the time of t 1; all calculations were replaced by 0 if the resulting value was negative.
3. A method of protecting a human impact injury in the event of a human impact event according to claim 1 wherein: the vehicle running speed in step S2 is obtained by calculation as follows:
assuming that the distance between the rear edge of the engine cover of the vehicle and the chest of the human body at a certain moment in the vehicle driving direction is d0, the running speed of the chest of the human body detected by the vehicle in the vehicle driving direction is v20, and the distance is required to be adjusted to d within the delta t time, the running speed v of the vehicle within the delta t time is d
Figure FDA0002900219870000011
4. A method of protecting a human impact injury in the event of a human impact event according to claim 1 wherein: the method for adjusting the inclination angle of the engine cover according to the posture of the human body in the step S3 is as follows:
if the chest-head direction of the human body is consistent with the advancing direction of the vehicle, the front edge of the engine cover is lifted to enable the inclination angle of the engine cover to be 0 degree; if the chest-head direction is opposite to the vehicle travel direction, the hood inclination is not changed.
5. A method of protecting a human impact injury in the event of a human impact event according to claim 1 wherein: step S4 detects that the person is about to fall to the ground at the time when the height of one of the head, chest or buttocks of the person is lower than the height of the front edge of the hood.
6. A method of protecting a human impact injury in the event of a human impact event according to claim 1 wherein: and S4, installing the external safety air bag in the front bumper of the vehicle, connecting the detonating device with the central console of the vehicle, wherein the width of the air bag is the same as that of the vehicle, the height of the air bag is the same as that of the lower edge of the front bumper, and the length of the air bag is 1.5 m.
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CN111572491A (en) * 2020-05-01 2020-08-25 东风汽车集团有限公司 Active hood system based on scene control
CN112572378B (en) * 2020-12-14 2022-01-28 长沙理工大学 Intelligent vehicle motion control method for protecting human-ground collision damage
CN112550526A (en) * 2020-12-21 2021-03-26 长沙理工大学 Intelligent vehicle head design method for protecting human-ground collision damage
CN112918424B (en) * 2021-03-01 2022-06-07 长沙理工大学 Air bag for reducing human-ground collision damage in ultra-low speed accident of intelligent automobile
CN112918470B (en) * 2021-03-01 2022-03-04 长沙理工大学 Intelligent automatic emergency braking method for protecting pedestrians

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CN101382376B (en) * 2007-09-05 2010-04-21 上海中集冷藏箱有限公司 Bottom side beam installation for refrigerating box
CN104228754B (en) * 2014-09-04 2019-10-29 浙江吉利控股集团有限公司 The control method and control system of the hood of vehicle
JP2018043735A (en) * 2016-09-16 2018-03-22 いすゞ自動車株式会社 Pedestrian protection device for vehicle
KR101996416B1 (en) * 2016-12-30 2019-10-01 현대자동차주식회사 Method and apparatus for pedestrian collision mitigation
JP2018150019A (en) * 2017-03-15 2018-09-27 本田技研工業株式会社 Airbag device

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