CN116001678A - Pedestrian protection system for carrying out man-machine interaction outside vehicle based on intelligent projection - Google Patents
Pedestrian protection system for carrying out man-machine interaction outside vehicle based on intelligent projection Download PDFInfo
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- CN116001678A CN116001678A CN202310185677.6A CN202310185677A CN116001678A CN 116001678 A CN116001678 A CN 116001678A CN 202310185677 A CN202310185677 A CN 202310185677A CN 116001678 A CN116001678 A CN 116001678A
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Abstract
Aiming at the problem that the existing pedestrian protection system does not consider pedestrian protection in a blind area, the pedestrian protection system for carrying out man-machine interaction outside a vehicle based on intelligent projection is provided, and comprises an identification center, a control center, projection equipment and early warning display equipment; the recognition center is responsible for acquiring the surrounding environment information of the vehicle and detecting the motion state of a person or object in front, the control center is responsible for calculating a projection area according to the vehicle information and a calculation program, judging when to trigger the projection equipment or emergency braking, the projection equipment is responsible for projecting a warning sign to the ground according to the calculated projection area, and the early warning display equipment is responsible for displaying the projection area and the recognized pedestrian position on a cab display. Compared with the prior art, the invention has the beneficial effects that: the pedestrian is close to the dangerous vehicle in the warning blind area in a mode of projecting the vehicle to the front ground, so that the pedestrian can primarily grasp the general direction of the vehicle, avoid in time, and accordingly the pedestrian passing through the blind area can be protected to the greatest extent.
Description
Technical Field
The invention relates to the technical field of vehicle safety, in particular to a pedestrian protection system for carrying out man-machine interaction outside a vehicle based on intelligent projection, which comprises a pedestrian protection method and a pedestrian protection device.
Background
At present, the promotion of economic level and the growth of traffic field all let the car play the important role in people's daily life, along with the vigorous development and the promotion of keeping quantity of car, people also pay more attention to driving safety.
Particularly in a complex traffic environment, a parked vehicle, building or other object at the front road side shields the visual field of a driver, and if a pedestrian suddenly "gets out" from a blind area at this time, the vehicle is not braked as soon as possible, so that traffic accidents are easily caused. According to incomplete statistics, traffic accidents in blind areas account for 41.1% of total accidents, and traffic safety in the blind areas is extremely poor, so that safety of drivers and pedestrians is threatened. The reason for this is mainly that the driver's visual field is blocked, the position and speed of the pedestrian in the blind area are difficult to grasp, the driver is late when the pedestrian is found, the driver is not aware of the driving state of the surrounding vehicles when part of the pedestrians pass through the road, the driver's visual field is also blocked, and the position and driving state of the vehicle are difficult to grasp.
Most of the existing pedestrian protection systems only carry out braking control on vehicles or warn pedestrians in advance through warning modes such as whistling and lamplight, but when the vehicles and pedestrians are in blind area environments, the simple modes such as whistling and lamplight can not effectively solve the problems, and if the pedestrians or the vehicles can notice the motion state of the other side in the blind area, the accident avoidance rate can be greatly improved.
Disclosure of Invention
Aiming at the problem that the existing achievements do not consider the pedestrian protection of the man-machine interaction outside the vehicle in the blind area, the invention provides a pedestrian protection system for the man-machine interaction outside the vehicle based on intelligent projection, which comprises the following components:
the recognition center is used for acquiring surrounding environment information of the vehicle, detecting whether pedestrians suddenly appear in the blind area in real time after the vehicle enters the blind area, and monitoring the motion state of the people or objects;
the control center is connected with the identification center and is used for calculating a projection range according to the vehicle information and a stored computer program so as to warn pedestrians passing through a road in a blind area and judge when to trigger projection equipment and when to trigger automatic emergency braking;
the projection equipment is connected with the control center and is used for projecting a warning sign on the ground in front of the vehicle;
the early warning display device is connected with the identification center and the control center and is used for displaying the projection position, the projection area and the position of the identified person or object in the cab;
the pedestrian protection method for carrying out man-machine interaction outside the vehicle based on intelligent projection comprises the following steps:
s1: the method comprises the steps that an identification center acquires surrounding environment information of a vehicle, when the condition that the vehicle enters a blind area environment is monitored, a control center acquires driving information of the vehicle, calculates a projection area to be projected in the current driving environment and triggers projection equipment;
s2: the projection equipment adjusts the projection area according to the calculation result of the control center, and projects a rectangular projection warning sign with a certain length and width to the front ground through the light source lamp, the baffle plate and the optical lens projection device to warn pedestrians passing through the road in the blind area;
s3: the recognition center continues to monitor the front driving environment, and when pedestrians or other moving objects appear in the red dangerous projection range, the control center triggers the automatic emergency braking system of the vehicle to completely brake the vehicle to avoid collision.
Optionally, the recognition center includes a recognition module and a detection module, where the recognition module includes a monocular camera, a binocular camera, a millimeter wave radar and a laser radar, and is used for recognizing a surrounding environment in a vehicle driving process, the detection module is used for detecting a position of a person or an object in the environment, and sending a detection result to the control center and the early warning display device control center, and determining whether to trigger the projection device and the automatic emergency braking system according to the detection result, where the early warning display device displays the detected position of the person or object on a display of the cab.
Optionally, the control center includes a calculation module, a vehicle information acquisition module and a memory, where the calculation module determines whether to trigger the projection device or emergency brake, and calculates an area to be projected according to information acquired by the vehicle information acquisition module, where the vehicle information acquisition module includes vehicle body information acquisition and motion information acquisition, the vehicle body information includes a vehicle size, the motion information includes a vehicle speed and an acceleration, and the memory is a computer readable storage medium on which computer program instructions are stored and can be directly called by the calculation module.
Optionally, the projection device is a CRT (Cathode Ray tube), DLP (Digital Light Processing, digital light processing technology), LCOS (Liquid Crystal On Silicon ) projection device or a laser projection device, and the projection range is adjusted according to an instruction sent from the control center, and then the projection is performed on the ground.
Alternatively, the projection device is mounted on the front side of the vehicle with the center of the two illumination lamps being offset downward.
Optionally, the early warning display device includes set up in the display of vehicle driver's cabin, show that projection area and the position of people or thing that detection module detected of projection device include the size of people or thing, for direction and the distance of vehicle, make things convenient for the driver to control the overall situation.
Optionally, the calculation method for calculating the projection area stored in the memory includes:
the projection width is:
D＝2D v
the projection length is as follows:
L＝vt rp +d v +C
wherein D is v Is the width of the vehicle body; v is the current speed of the vehicle; t is t rp Is pedestrian reaction time; d, d v The driving distance of the vehicle under the maximum braking; c is the psychological safety braking distance of pedestrians, and the distance is 3-5m; t is t lag The braking time of the braking system; a, a v Taking 0.8g for the maximum deceleration of the vehicle;
the pedestrian reaction time comprises pedestrian perception time, pedestrian reading time and pedestrian decision time, the pedestrian perception time is 0.57s, the pedestrian reading time is 0.3s, the pedestrian decision time is 0.2s, the pedestrian psychological safety braking distance refers to the distance between the vehicle and the pedestrian after the vehicle is completely stopped, so that the pedestrian can feel safe and comfortable psychologically, the braking time of the braking system is assumed to be ready after the vehicle enters a blind area, and therefore the braking time of the braking system is ignored.
Alternatively, the blind area environment refers to an environment in which the driver's view is partially blocked and the traffic condition cannot be completely seen, for example, the vehicle is normally running in a lane, and since other vehicles are parked on the left or right lanes, the driver's view is blocked, so that the driver cannot see whether a pedestrian is passing through a road on the left or right sidewalk, or a building beside the road blocks the driver's view, so that the driver cannot see the other vehicle or pedestrian.
Alternatively, the projection shape is rectangular and the projection angle is 45 °.
Optionally, the projection pattern includes a red area and a blue area, so that pedestrians can know the distance of the vehicle conveniently, if the pedestrians can pass through the blue projection area quickly, dangerous vehicles can be avoided safely, the red projection area is an unavoidable collision area, and at the moment, pedestrians are required to be reminded of being unable to break into the red area;
when the projection length (from the vehicle running direction) is smaller than the vehicle maximum braking running distance and the safety distance, namely 0.ltoreq.L.ltoreq.d v When +C, a red projection area is used for projecting a red pattern, and when the projection length is longer than the maximum distance of the vehicle under brakingAnd a safety distance but less than the total length, i.e. d v +C≤L≤vt rp +d v In +C, a blue pattern is projected as a blue projection area.
Optionally, the projected indicia projected by the projection device comprises a graphic, symbol, text, or projection covering the hazard zone.
Optionally, the memory stores vehicle body information, including data information such as length, width, height, quality, wheelbase, etc. of the vehicle, so that the vehicle body information of the vehicle information acquisition module can acquire data, and further calculate the projection area.
Optionally, the motion information of the vehicle information acquisition module is acquired, the vehicle motion state information is acquired by a vehicle speed sensor, a brake pressure sensor and a brake system detector, and required data is sent to the calculation module for the calculation module to calculate the projection area.
Compared with the prior art, the technical scheme of the invention has the beneficial effects that: can be through the projection to the ground projection of certain distance after the vehicle is driven into the blind area to warn to be about to cross the road or have dangerous vehicle to be close to in the pedestrian blind area of crossing the road, make the pedestrian can preliminary grasp the approximate position that the vehicle is located, in time dodge, can furthest protect the pedestrian who passes in the blind area according to this.
Drawings
FIG. 1 is a system block diagram of the present invention;
FIG. 2 is a schematic diagram of the present invention;
wherein, corresponding reference numerals are as follows: 10-blue area projected, 20-red area projected, 30-projection angle.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the present patent;
the following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Fig. 1 is a block diagram of a pedestrian protection system for off-board man-machine interaction based on intelligent projection according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of a pedestrian protection system for performing man-machine interaction outside a vehicle based on intelligent projection according to an embodiment of the invention.
As shown in fig. 1, the pedestrian protection system for performing man-machine interaction outside a vehicle based on intelligent projection in the embodiment of the invention comprises an identification center 01, a control center 02, a projection device 03 and an early warning display device 04. The recognition center 01 is used for acquiring surrounding environment information of a vehicle, detecting whether a pedestrian suddenly appears in a blind area in real time after the vehicle enters the blind area, and monitoring the motion state of the person or object; the control center 02 is connected with the recognition center 01 and is used for calculating a projection range according to the vehicle information and a stored computer program so as to warn pedestrians passing through a road in a dead zone and judge when to trigger projection equipment and when to trigger automatic emergency braking; the projection device 03 is connected with the control center 02 and is used for projecting warning signs on the ground in front of the vehicle; the early warning display device 04 is connected with the identification center 01 and the control center 02 and is used for displaying the projection position, the projection area and the position of the identified person or object in the cab.
In one embodiment of the present invention, the control center 02 includes a calculation module that determines whether to trigger the projection device or emergency braking and calculates an area to be projected based on information acquired by the vehicle information acquisition module, the vehicle information acquisition module including vehicle body information acquisition and motion information acquisition, the vehicle body information including vehicle size, the motion information including vehicle speed, acceleration, and a memory that is a computer-readable storage medium on which computer program instructions are stored and on which vehicle body information including data information of length, width, height, mass, wheelbase of the vehicle is stored.
In one embodiment of the present invention, the projection device 03 is installed at the center of two illumination headlamps at the front side of the vehicle and is a CRT (Cathode Ray tube), DLP (Digital Light Processing, digital light processing technology), LCOS (Liquid Crystal On Silicon ) projection device or a laser projection device, and the projection range is adjusted according to the instruction sent from the control center and then projected onto the ground.
In one embodiment of the invention, the warning display device 04 includes a display disposed in the vehicle cab, and the projection area of the display projection device and the position of the person or object detected by the detection module include the size of the person or object, the direction and distance relative to the vehicle.
In one embodiment of the invention, the motion information of the vehicle information acquisition module is acquired, and the vehicle motion state information is acquired by a vehicle speed sensor, a brake pressure sensor and a brake system detector.
In one embodiment of the invention, the projected logo projected by the projection device 03 comprises a graphic, symbol, text or projection covering the hazard zone.
For a certain vehicle loaded with the pedestrian protection system for performing man-machine interaction outside the vehicle based on intelligent projection, entering a blind area environment in a certain running process, the system protects pedestrians by the following modes:
s1: when the recognition center monitors that the vehicle enters a blind zone, a vehicle information acquisition module of the control center acquires vehicle driving information, including the size of the vehicle body, the speed and the acceleration, sends the information to a calculation module, calculates a projection area required to be projected under the current driving environment according to a computer program stored in a memory, triggers projection equipment, and the calculation program in the memory is that
The projection width is:
D＝2D v
the projection length is as follows:
L＝vt rp +d v +C
wherein D is v Is the width of the vehicle body; v is the current speed of the vehicle; t is t rp The pedestrian reaction time comprises pedestrian perception time, pedestrian reading time and pedestrian decision time, wherein the pedestrian perception time is 0.57s, the pedestrian reading time is 0.3s, and the pedestrian decision time is 0.2s; d, d v The driving distance of the vehicle under the maximum braking; c is the psychological safety braking distance of pedestrians, and the distance is 3-5m; t is t lag As the braking time of the braking system, it is assumed that the braking system is ready after the vehicle enters the blind area, and therefore the braking time of the braking system is ignored; a, a v For the maximum deceleration of the vehicle, 0.8g was taken.
S2: the projection equipment adjusts the projection area according to the calculation result, and projects a rectangular projection warning sign with a certain length and width to the ground through a light source lamp, a baffle plate and an optical lens projection device to warn pedestrians passing through a road in a blind area, wherein the projection angle 30 is 45 degrees, the projection pattern comprises a red area 20 and a blue area 10, and when the projection length (from the running direction of the vehicle) is smaller than the maximum braking running distance and the safety distance of the vehicle, namely, L is more than or equal to 0 and less than or equal to d v In +C, a red projection area is projected with a red pattern, and when the projection length is longer than the maximum distance and the safe distance of the vehicle under braking but shorter than the total length, i.e. d v +C≤L≤vt rp +d v In +C, a blue pattern is projected as a blue projection area.
S3: when the recognition center monitors that pedestrians or other moving objects appear in the red dangerous projection range, the control center triggers an automatic emergency braking system of the vehicle to completely brake the vehicle to avoid collision.
According to the pedestrian protection system for performing man-machine interaction outside the vehicle based on intelligent projection, which is provided by the embodiment of the invention, the surrounding environment information of the vehicle is acquired in real time through the identification center, and whether pedestrians appear in a front dangerous area is detected; calculating a projection range and projection time by a control center according to the acquired vehicle information and a stored computer program, warning pedestrians passing through a road in a blind area, and judging when to trigger projection equipment and when to trigger emergency braking; and projecting a warning sign to the ground in the blind area through the projection equipment, and displaying the projection position, the projection area, the recognized position, the recognized direction and the recognized size of the pedestrian on a cab display through the early warning display equipment. Therefore, after the vehicle enters the blind area, the projection of a certain distance is projected to the ground so as to warn that dangerous vehicles approach to the road or are approaching to the pedestrian blind area on the road, so that the pedestrian can primarily grasp the general direction of the vehicle, avoid in time, and the pedestrian passing through the blind area can be protected to the greatest extent.
It should be apparent that the foregoing examples of the invention are provided merely for the purpose of clearly illustrating the invention and are not intended to limit the embodiments of the invention, and that other variations or modifications may be made in the various forms as would occur to those skilled in the art based on the teachings herein. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.
Claims (7)
1. Pedestrian protection system based on intelligent projection carries out man-machine interaction outside car, characterized by comprising:
the recognition center is used for acquiring surrounding environment information of the vehicle, detecting whether pedestrians appear in the blind area in real time after the vehicle enters the blind area, and monitoring the motion state of the people or objects;
the control center is connected with the identification center and is used for calculating a projection range according to the vehicle information and a stored computer program so as to warn pedestrians passing through a road in a blind area and judge when to trigger projection equipment and when to trigger emergency braking;
the projection equipment is connected with the control center and is used for projecting a warning sign on the ground in front of the vehicle;
the early warning display device is connected with the identification center and the control center and is used for displaying the projection position, the projection area and the position of the identified person or object in the cab;
the pedestrian protection method for carrying out man-machine interaction outside the vehicle based on intelligent projection comprises the following steps:
s1: the method comprises the steps that an identification center acquires surrounding environment information of a vehicle, when the condition that the vehicle enters a blind area environment is monitored, a control center acquires driving information of the vehicle, calculates a projection area to be projected in the current driving environment and triggers projection equipment;
s2: the projection equipment adjusts the projection area according to the calculation result of the control center, and projects a rectangular projection warning sign with a certain length and width to the front ground through the light source lamp, the baffle plate and the optical lens projection device to warn pedestrians passing through the road in the blind area;
s3: the recognition center continues to monitor the front driving environment, and when pedestrians or other moving objects appear in the red dangerous projection range, the control center triggers the automatic emergency braking system of the vehicle to completely brake the vehicle to avoid collision.
2. The pedestrian protection system for performing man-machine interaction outside a vehicle based on intelligent projection according to claim 1, wherein the recognition center comprises a recognition module and a detection module, the recognition module comprises a monocular camera, a binocular camera, a millimeter wave radar and a laser radar and is used for recognizing surrounding environment in the running process of the vehicle, and the detection module is used for detecting the position of people or objects in the environment and sending detection results to the control center and the early warning display device.
3. The pedestrian protection system for off-vehicle human-computer interaction based on intelligent projection of claim 1, wherein the control center comprises a calculation module, a vehicle information acquisition module and a memory, wherein the calculation module determines whether to trigger the projection device or the automatic emergency braking system, and calculates an area to be projected according to information acquired by the vehicle information acquisition module, the vehicle information acquisition module comprises a vehicle body information acquisition and a motion information acquisition, the vehicle body information comprises a vehicle size, the motion information comprises a vehicle speed and an acceleration, and the memory is a computer-readable storage medium on which computer program instructions are stored.
4. The pedestrian protection system for performing man-machine interaction outside a vehicle based on intelligent projection according to claim 1, wherein the projection device is CRT, DLP, LCOS projection device or laser projection device, and the motion information of the vehicle information acquisition module is acquired by a vehicle speed sensor, a brake pressure sensor and a brake system detector.
5. The pedestrian protection system for off-board human-computer interaction based on intelligent projection of claim 1, wherein the early warning display device comprises a display arranged in a cab of the vehicle, and the projection area of the display projection device and the position of the person or object detected by the detection module comprise the size of the person or object, the direction and the distance relative to the vehicle.
6. The pedestrian protection system for performing man-machine interaction outside a vehicle based on intelligent projection according to claim 1, wherein the calculation method for calculating the projection area stored in the memory is as follows:
the projection width is:
D＝2D v
the projection length is as follows:
L＝vt rp +d v +C
wherein D is v Is the width of the vehicle body; v is the current speed of the vehicle; t is t rp Is pedestrian reaction time; d, d v The driving distance of the vehicle under the maximum braking; c is the psychological safety braking distance of pedestrians, and the distance is 3-5m; t is t lag The braking time of the braking system; a, a v Taking 0.8g for the maximum deceleration of the vehicle;
the pedestrian reaction time comprises pedestrian perception time, pedestrian reading time and pedestrian decision time, wherein the pedestrian perception time is 0.57s, the pedestrian reading time is 0.3s, and the pedestrian decision time is 0.2s.
7. The pedestrian protection system for off-vehicle human-computer interaction based on intelligent projection of claim 1, wherein the projected pattern comprises a red area and a blue area:
when the projection length (from the vehicle running direction) is smaller than the vehicle maximum braking running distance and the safety distance, namely 0.ltoreq.L.ltoreq.d v In +C, a red projection area is projected with a red pattern, and when the projection length is longer than the maximum distance and the safe distance of the vehicle under braking but shorter than the total length, i.e. d v +C≤L≤vt rp +d v In +C, a blue pattern is projected as a blue projection area.
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| CN202310185677.6A CN116001678A (en) | 2023-03-01 | 2023-03-01 | Pedestrian protection system for carrying out man-machine interaction outside vehicle based on intelligent projection |
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| CN202310185677.6A CN116001678A (en) | 2023-03-01 | 2023-03-01 | Pedestrian protection system for carrying out man-machine interaction outside vehicle based on intelligent projection |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117644815A (en) * | 2024-01-29 | 2024-03-05 | 深圳市欧冶半导体有限公司 | Blind zone alarming method, device, equipment and system based on intelligent car lamp system |
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2023
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117644815A (en) * | 2024-01-29 | 2024-03-05 | 深圳市欧冶半导体有限公司 | Blind zone alarming method, device, equipment and system based on intelligent car lamp system |
| CN117644815B (en) * | 2024-01-29 | 2024-04-02 | 深圳市欧冶半导体有限公司 | Blind zone alarming method, device, equipment and system based on intelligent car lamp system |
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