Tunnel safety prompting system and method based on real-time vehicle speed

Abstract

The invention provides a tunnel safety prompting system and method based on real-time vehicle speed, and belongs to the technical field of driving safety guidance. The tunnel safety prompting system comprises a vehicle speed information prompting screen arranged outside a tunnel entrance, a first group of vehicle speed detection equipment arranged on a detection support outside the tunnel entrance, and a second group of vehicle speed detection equipment arranged on a detection support outside the tunnel entrance; the vehicle sensors are arranged on the two sides of a road between the outside of the tunnel entrance and the tunnel entrance in a partitioned mode, the second set of vehicle speed detection devices are arranged at a plurality of positions inside and outside the tunnel respectively, the lane changing acousto-optic warning indicator is arranged on the outer wall of the tunnel, and the second vehicle information processor is arranged on the wall of the tunnel entrance; the first vehicle information processor is arranged on a tunnel entrance wall body; according to the invention, acousto-optic guidance can be carried out on vehicles which do not change lanes in time, the speed difference between the vehicles can be reduced by carrying out optimal speed prompt on the vehicles entering the tunnel in advance, meanwhile, the driving influence caused by a black hole effect when the vehicles enter the tunnel is reduced, and traffic accidents are effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of driving safety guidance, and in particular to a tunnel safety prompting system and method based on real-time vehicle speed. Background Art

[0002] With the continuous improvement of my country's infrastructure, the mileage of expressways is increasing. For mountain expressways, due to the limitations of terrain and other conditions, as well as the continuous improvement and development of construction methods, the proportion of tunnels is increasing. According to surveys, tunnels account for up to 50% of some expressways. Due to the particularity of tunnels, they often become frequent sections of expressway traffic accidents. Once they occur, the difficulty of rescue and the consequences are far greater than those of ordinary sections. According to a survey of a mountain expressway in my country, rear-end collisions are the main form of traffic accidents in tunnel sections, accounting for as high as 65%. The second largest cause is collisions with guardrails, central isolation barriers, and tunnel walls, accounting for about 14%.

[0003] Most drivers will experience severe glare when entering or exiting highway tunnels due to the large changes in brightness inside and outside the tunnel. The glare will cause the driver to slow down when entering or exiting the tunnel. If the following vehicle does not react in time, it will cause a rear-end collision in the tunnel, posing a safety hazard. At present, most of the ways to reduce glare in my country are to set up a dimming shed outside the tunnel or adjust the brightness of the lights inside the tunnel. However, this method requires too much initial investment and consumes a lot of energy. In addition, the method of adjusting the dimming shed or the brightness of the lights inside the tunnel in real time with sunlight is relatively complicated and cannot be fully applied to all tunnels. At the same time, due to the complex mountainous terrain of some tunnels, it is impossible to achieve a good road connection and transition at the entrance of the tunnel. Vehicles may collide or scratch the tunnel wall due to failure to change lanes in time.

[0004] At present, most domestic research has started from the aspect of speed change, in order to solve the traffic accidents caused by the changes in light inside and outside the tunnel and the special linear design. However, most studies on the exploration of reasonable speed in tunnels still remain at the static speed limit. This result will firstly lead to increased driving difficulties for drivers due to different speed limit requirements, and secondly, it cannot adapt to the changes in the difference in internal and external light caused by the changes in sunlight with seasons or a day. Summary of the invention

[0005] The purpose of the present invention is to provide a tunnel safety prompt system and method based on real-time vehicle speed to overcome the problems existing in the prior art. The present invention can calculate the optimal entry speed of vehicles entering the tunnel in real time, and dynamically display the optimal entry speed through a vehicle speed information prompt screen, so as to reduce the speed difference of each vehicle, reduce the large front and rear acceleration of the vehicle, and reduce the occurrence of traffic accidents such as rear-end collisions in the tunnel. It can also enable vehicles to receive timely reminders when they fail to change lanes, so that the deceleration effect caused by the tunnel glare effect when the vehicles entering the tunnel entrance are driving at this speed is minimized, and the speed is consistent with the traffic speed in the tunnel, thereby ensuring driving safety and improving driving comfort.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A tunnel safety prompt system based on real-time vehicle speed, comprising: The vehicle speed information prompt screen set outside the tunnel entrance is used to prompt the optimal speed for entering the tunnel; A first set of vehicle speed detection equipment is arranged on a detection bracket outside the tunnel entrance, and is used to detect the speed information of vehicles that fail to change lanes in time and transmit it to a first vehicle information processor; the first vehicle information processor is arranged on the wall of the tunnel entrance, and is used to calculate the minimum lane change distance and the minimum braking distance; The vehicle sensors are arranged in sections on both sides of the road between the outside of the tunnel entrance and the tunnel entrance, and are used to receive the minimum lane change distance and the minimum braking distance transmitted by the first vehicle information processor; A second group of vehicle speed detection devices are respectively arranged at several positions inside and outside the tunnel, for obtaining vehicle speed information and transmitting it to a second vehicle information processor; the second vehicle information processor is arranged on the wall of the tunnel entrance, for calculating the vehicle flow speed and the optimal speed for entering the tunnel; The lane change sound and light warning device installed on the outer wall of the tunnel is used to warn the target vehicle to change lanes or emergency brake; The vehicle speed information prompt screen, the first set of vehicle speed detection equipment, the vehicle sensor, the second set of vehicle speed detection equipment, the lane change sound and light warning device, the second vehicle information processor and the first vehicle information processor are all equipped with wireless transmission equipment; Furthermore, the vehicle speed information prompt screen is arranged 250 m outside the tunnel entrance; the first set of vehicle speed detection equipment is arranged on a detection bracket 150 m outside the tunnel entrance; the vehicle sensors are arranged in sections on both sides of the road between 150 m outside the tunnel entrance and the tunnel entrance; Furthermore, the vehicle speed information prompt screen is a variable information prompt screen, which automatically updates the optimal entry speed of vehicles entering the tunnel under the current sunlight conditions every 10 minutes; Furthermore, the content of the vehicle speed information prompt screen is a lane-by-lane vehicle speed prompt; Furthermore, the second group of vehicle speed detection devices are respectively arranged at four positions inside and outside the tunnel, specifically: the first vehicle speed detection device is arranged 50 m outside the tunnel entrance, the second vehicle speed detection device is arranged at the tunnel entrance, the third vehicle speed detection device is arranged 100 m inside the tunnel entrance, and the fourth vehicle speed detection device is arranged at the tunnel exit.

[0007] A tunnel safety prompt method based on real-time vehicle speed, based on the above-mentioned tunnel safety prompt system based on real-time vehicle speed, comprises the following steps: (1) The second vehicle speed detection device obtains vehicle speed information and transmits the vehicle speed information to the second vehicle information processor. The second vehicle information processor calculates the vehicle flow speed and the optimal tunnel entry speed and transmits the optimal tunnel entry speed to the vehicle speed information prompt screen. The vehicle speed information prompt screen receives the optimal tunnel entry speed and displays it. (2) the first group of vehicle speed detection devices detects the speed information of the vehicle that fails to change lanes in time, and transmits the speed information of the vehicle that fails to change lanes in time to the first vehicle information processor; (3) the first vehicle information processor calculates a minimum lane change distance and a minimum braking distance, and transmits the minimum lane change distance and the minimum braking distance to a vehicle sensor; (4) If the vehicle sensor senses that the target vehicle has not changed lanes within the minimum lane change distance, the vehicle sensor transmits a warning command to the lane change sound and light warning device, and then execute (5); If the vehicle sensor senses that the target vehicle changes lanes within the minimum lane change distance, execute (2) again; (5) The lane change sound and light warning device receives the warning command and issues a warning; Furthermore, the optimal entry speed in (1) is a value obtained by weighting 50% of the vehicle speed detected by the second group of vehicle speed detection equipment; Furthermore, the specific formula for calculating the minimum lane change distance in (3) is as follows: S min = + + ; Where: is the visual recognition distance, that is, the distance the driver travels from seeing the light warning to understanding that there is a tunnel ahead and needs to change lanes. The calculation formula is: ; is the reaction distance, that is, the distance the driver turns on the turn signal and starts turning. The calculation formula is: ; is the distance traveled by the vehicle after entering the target lane, and the calculation formula is: ; In the formula, is the speed of the target vehicle; The time it takes for the driver to see the light warning and understand that there is a tunnel ahead and that he needs to change lanes. The time required for the driver to turn on the turn signal and start turning; is the lane change time of the target vehicle; is the running speed of the target vehicle when turning; Furthermore, the specific formula for calculating the minimum braking distance in (3) is as follows: L= + ; Where: The distance from hearing the warning to understanding that there is a tunnel wall ahead and the driver must stop the car in time is calculated as follows: ; is the braking deceleration distance, that is, the distance the vehicle decelerates from its original speed to a stop. The calculation formula is: ; In the formula, is the speed of the target vehicle; The time from hearing the warning sound to realizing that there is a tunnel wall ahead and the vehicle must stop in time; a To assume constant acceleration; Furthermore, the above (5) is specifically: The lane change sound and light warning device receives the warning instruction and issues a bright light warning of "please change lanes"; If the target vehicle still does not change lanes after receiving the bright light warning, when the target vehicle reaches the minimum braking distance, the lane change sound and light warning device will repeat the sound warning of "Please emergency brake immediately"; If the target vehicle changes lanes after receiving the bright light warning, execute (2) again.

[0008] The above technical solution has the following advantages or beneficial effects: The present invention provides a tunnel safety prompt system based on real-time vehicle speed. The optimal speed for entering the tunnel is displayed in real time through a vehicle speed information prompt screen. The driver can adjust the speed in advance to avoid accidents caused by speed mismatch when entering the tunnel; the first group of vehicle speed detection equipment can detect the speed information of vehicles that have not changed lanes in time, and calculate the minimum lane change distance and the minimum braking distance through the first vehicle information processor, and convey them to the driver through the vehicle sensor, which helps them make safe driving decisions in time; the lane change sound and light warning device can warn the target vehicle to change lanes or emergency brake when necessary, further reducing the risk of accidents; the system encourages the driver to enter the tunnel at the optimal speed through real-time monitoring and prompting. Tunnels help reduce traffic congestion in tunnels and improve overall traffic flow. Timely lane change prompts and warnings also help reduce traffic interruptions caused by improper lane changes or emergency braking. Drivers can receive timely and accurate safety prompts during driving, which helps improve their driving experience and confidence. The system's wireless transmission equipment ensures the real-time and accuracy of information, allowing drivers to respond more quickly and accurately, thereby reducing the occurrence of traffic accidents such as rear-end collisions in tunnels, and minimizing the deceleration effect caused by the tunnel glare effect when vehicles entering the entrance travel at this speed, and keeping consistent with the traffic speed in the tunnel, thereby ensuring driving safety and improving driving comfort.

[0009] Furthermore, the speed information prompt screen is set 250 meters outside the tunnel entrance, which provides drivers with enough time and distance to adjust the speed to adapt to the tunnel environment they are about to enter. Early warning helps reduce traffic accidents caused by sudden changes in speed or traffic conditions. According to surveys, traffic accidents generally begin to increase 250 meters from the tunnel entrance. Vehicles entering the tunnel begin to decelerate at a large acceleration at 150 meters. Therefore, the speed information prompt screen is set 250 meters outside the tunnel entrance, which provides drivers with enough time and distance to adjust the speed to adapt to the tunnel environment they are about to enter. Early warning helps reduce traffic accidents caused by sudden changes in speed or traffic conditions. According to surveys, traffic accidents generally begin to increase 250 meters from the tunnel entrance. Vehicles entering the tunnel begin to decelerate at a large acceleration at 150 meters. The first set of vehicle speed detection equipment is set 150 meters outside the tunnel entrance, which can not only capture the speed information of vehicles about to enter the tunnel, but also ensure that there is enough time for data processing and decision-making before the vehicle approaches the tunnel entrance. The system can promptly detect vehicles with abnormal speed or vehicles that fail to change lanes in time, and issue prompts to the driver through vehicle sensors or other warning devices; the vehicle sensors are divided and set on both sides of the road between 150 meters outside the tunnel entrance and the tunnel entrance, which can more accurately monitor the driving status and position of the vehicle, so that the system can provide more accurate prompts and warnings according to the actual situation of the vehicle, further improving the safety of tunnel driving; the above layout design not only improves the monitoring and early warning capabilities of the system, but also optimizes the process of information processing and transmission. The collaborative work between various devices enables the system to collect, process and transmit information more efficiently, thereby realizing real-time monitoring and management of tunnel traffic conditions.

[0010] Furthermore, starting from the change in vehicle speed itself, by obtaining the deceleration situation of the moving vehicle when entering and exiting the tunnel, it indirectly reflects the influence of the glare effect caused by external sunlight and light inside the tunnel, thereby providing the best tunnel driving speed recommendation for vehicles that have not entered the tunnel.

[0011] Furthermore, the variable information prompt screen can correspond to each lane, and provide the best vehicle entry speed for the fast lane and the driving lane at the same time, prompting the best tunnel entry speed matching the lane, ensuring that the information received by the driver is always the most accurate and most in line with the current environmental conditions, thereby improving driving safety and comfort. The best speed prompt for each lane can also provide a more refined and reasonable driving speed for traffic in different lanes, avoiding the impact of excessive speed differences between different lanes; by updating the best entry speed in real time, the system can help the driver adjust the speed before entering the tunnel to adapt to the light changes and possible visual obstructions in the tunnel, helping to reduce traffic accidents caused by speed mismatch or unclear vision.

[0012] Furthermore, lane-by-lane speed warnings can guide drivers to choose the appropriate speed according to their lanes, helping to reduce speed differences between lanes, thereby improving the stability and efficiency of traffic flow; in the limited space of a tunnel, it can effectively reduce lane changes and traffic conflicts caused by speed mismatches; by clarifying the speed limits of each lane, drivers can more clearly understand the driving rules in the tunnel and avoid traffic accidents such as rear-end collisions and scratches caused by improper speed. Especially near the tunnel entrance, lane-by-lane speed warnings can help drivers adjust their speed in advance to adapt to light changes and road conditions in the tunnel.

[0013] Furthermore, by setting up multiple speed detection devices inside and outside the tunnel, the system can comprehensively monitor the entire driving process of the vehicle from approaching the tunnel to leaving the tunnel. Comprehensive monitoring helps to promptly discover speed anomalies or potential safety hazards, so that timely measures can be taken to avoid accidents; the location selection of each speed detection device enables the system to obtain the speed information of the vehicle at different stages, and precise control helps to ensure that the vehicle travels at a safe and stable speed in the tunnel.

[0014] The present invention also provides a tunnel safety prompt method based on real-time vehicle speed, wherein the vehicle speed information is obtained in real time through the second group of vehicle speed detection equipment, and the traffic speed and the optimal speed for entering the tunnel are calculated. The vehicle speed information prompt screen can timely display the optimal speed for entering the tunnel to the driver, helping them to make reasonable driving decisions. The real-time dynamic prompt helps to reduce traffic accidents caused by speed mismatch or speeding, and significantly improves the safety of tunnel driving; the first group of vehicle speed detection equipment can detect the speed information of vehicles that have not changed lanes in time, and calculate the minimum lane change distance and the minimum braking distance through the first vehicle information processor. When the vehicle sensor senses that the target vehicle has not changed lanes within the minimum lane change distance, the lane change sound and light alarm will issue a warning in time to remind the driver to take emergency measures. The intelligent early warning mechanism helps to prevent traffic accidents caused by improper lane changes; the method helps the driver to drive more confidently by providing real-time and accurate vehicle speed and lane change prompts. At the same time, the use of the sound and light alarm also makes the warning information more intuitive and easy to understand, thereby enhancing the driver's driving experience.

[0015] Furthermore, by calculating 50% of the vehicle speed of the traffic flow and weighting it to obtain the optimal entry speed, this method can ensure that most vehicles can enter the tunnel at a relatively consistent speed, reducing the safety hazards caused by speed differences, and helping to reduce the risk of traffic accidents such as rear-end collisions and scratches caused by speed mismatch; the setting of the optimal entry speed takes into account the overall speed distribution of the traffic flow, which helps to form a stable and orderly traffic flow. When vehicles enter the tunnel at a speed close to the optimal entry speed, it can reduce lane changes and emergency braking caused by speed differences, thereby improving the traffic efficiency and safety of the tunnel.

[0016] Furthermore, by accurately calculating the minimum lane change distance, the method can ensure that the driver completes the lane change operation within a sufficiently safe distance, which helps to reduce traffic accidents caused by improper lane changes and improve the safety of tunnel driving; the parameters in the formula (such as recognition time, reaction time, lane change time, etc.) are all based on actual driving experience and data settings, which can reflect the driver's reaction and operation ability in a real driving environment, and help enhance the driver's adaptability to the tunnel lane change environment.

[0017] Furthermore, by accurately calculating the minimum braking distance, it can ensure that the driver has enough time and distance to slow down and stop after hearing the sound warning to avoid collision with the tunnel wall, which helps to significantly improve safety in emergency braking situations; the hearing recognition distance part of the formula takes into account the time from the driver hearing the sound warning to understanding that there is a tunnel wall ahead and must stop in time. It is set based on actual driving experience and data, which helps to optimize the driver's reaction time and improve the ability to respond in emergency situations.

[0018] Furthermore, by first issuing a bright light warning of "please change lanes" and then repeating the voice warning of "please brake immediately" when necessary, it can ensure that the driver receives warning information on multiple perception channels. The bright light warning can quickly attract the driver's attention, and the voice warning can further emphasize the severity of the emergency, thereby significantly improving the warning effect; when the driver sees the bright light warning, there will be a certain amount of time to assess the situation and respond. If the driver fails to change lanes in time, when the vehicle reaches the minimum braking distance, the voice warning will remind them again to take emergency braking measures, which can enhance the driver's emergency response capabilities in emergency situations and reduce the occurrence of traffic accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a tunnel safety prompt system based on real-time vehicle speed according to the present invention; Figure 2 A schematic flow chart of a tunnel safety prompt method based on real-time vehicle speed according to the present invention; In the figure, 1-vehicle speed information prompt screen; 2-first group of vehicle speed detection equipment; 3-vehicle sensor; 4-second group of vehicle speed detection equipment; 4-1-first vehicle speed detection equipment; 4-2-second vehicle speed detection equipment; 4-3-third vehicle speed detection equipment; 4-4-fourth vehicle speed detection equipment; 5-lane change sound and light warning device; 6-second vehicle information processor; 7-first vehicle information processor. DETAILED DESCRIPTION

[0020] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it. In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention. It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] Embodiment 1: like Figure 1 As shown, the present invention provides a tunnel safety prompt system based on real-time vehicle speed, comprising: The vehicle speed information prompt screen 1 is set at 250 m outside the tunnel entrance, which is used to prompt the optimal speed for entering the tunnel. According to investigations, traffic accidents generally begin to increase 250 m away from the tunnel entrance, and vehicles entering the tunnel begin to decelerate at a large acceleration at 150 m. Therefore, prompting at 250 m can enable drivers to prepare for deceleration in advance, achieve a smoother and safer deceleration process, and avoid rear-end collisions caused by excessive acceleration changes; the first group of vehicle speed detection equipment 2 is set on the detection bracket 150 m outside the tunnel entrance, which is used to detect the speed information of vehicles that fail to change lanes in time and transmit it to the first vehicle information processor 7; the partition is set at 150 m outside the tunnel entrance m to the tunnel entrance, are used to detect whether the vehicle has not changed lanes safely and timely during this distance, and receive the minimum lane change distance and the minimum braking distance from the first vehicle information processor 7; a second group of vehicle speed detection devices 4 are respectively arranged at 4 positions inside and outside the tunnel, each group has 2 radar speed meters, which are used to measure the speed of vehicles in each lane, obtain vehicle speed information and transmit it to the second vehicle information processor 6, specifically: the first vehicle speed detection device 4-1 is arranged 50 m outside the tunnel entrance, and is arranged by a gantry type; the second vehicle speed detection device 4-2 is arranged at the tunnel entrance, and is arranged by an attachment type; the third vehicle speed detection device 4-3 is arranged 100 m inside the tunnel entrance, and is arranged by an attachment type; the fourth vehicle speed detection device 4-4 is arranged at the tunnel exit, and is arranged by an attachment type; the vehicle speeds of the four positions where the vehicle speed detection is arranged are generally different, and the second vehicle information processor 6 calculates 10 The 50% speed of the traffic flow at four different positions within 1 minute is used as the representative speed of the four speed measurement points. The speeds of the four speed measurement points are weighted and assigned to obtain the optimal vehicle speed for entering the tunnel. The speed at 50 m away from the tunnel entrance accounts for 30%, the speed at the tunnel entrance accounts for 30%, the speed at 100 m away from the entrance in the tunnel accounts for 20%, and the speed at the tunnel exit accounts for 20%; the lane change sound and light alarm 5 set on the outer wall of the tunnel is used to warn the target vehicle to change lanes or emergency brake; the second vehicle information processor 6 set on the wall of the tunnel entrance is used to receive the four second groups of speed detection devices 4 and calculate the traffic speed to obtain the real-time optimal vehicle speed for entering the tunnel, and transmit the information to the speed information prompt screen 1. The speed information prompt screen 1 dynamically displays the optimal entry speed to reduce the speed difference of each vehicle and reduce the large front and rear acceleration of the vehicle, thereby reducing the occurrence of traffic accidents such as rear-end collisions in the tunnel; the first vehicle information processor 7 set on the wall of the tunnel entrance is used to receive real-time information from the vehicle speed detection device and calculate the minimum lane change distance and the minimum braking distance;The vehicle speed information prompt screen 1, the first set of vehicle speed detection equipment 2, the vehicle sensor 3, the second set of vehicle speed detection equipment 4, the lane change sound and light warning device 5, the second vehicle information processor 6 and the first vehicle information processor 7 are all equipped with wireless transmission equipment for timely transmission of corresponding information; Preferably, the vehicle speed information prompt screen 1 is a variable information prompt screen, which automatically updates the optimal entry speed of vehicles entering the tunnel under the current sunlight every 10 minutes, so that vehicles 250 meters away from the tunnel entrance can predict the tunnel driving conditions in advance and prepare for deceleration in advance, reduce speed differences, and smoothly transition the black hole effect caused by the particularity of the tunnel, thereby ensuring driving safety; Preferably, the vehicle speed information prompt screen 1 is composed of LED lights. According to the real-time changes of the vehicle speed information of the road section, the speed value of the vehicle speed information prompt screen 1 is adjusted accordingly. Considering the complexity of the tunnel section, the variable vehicle speed information prompt screen 1 adjusts the speed value in real time, which is more conducive to solving the problems of tunnel discreteness and excessive front and rear speed difference; Preferably, the vehicle speed information prompt screen 1 is a lane-by-lane vehicle speed prompt, capable of providing an optimal vehicle speed prompt; Preferably, the vehicle speed information prompt screen 1 is a gantry-type variable information prompt screen, which can correspond to each lane, and provide the best vehicle entering the tunnel speed for the fast lane and the driving lane at the same time, and prompt the best tunnel entering speed that matches the lane. Different lanes in general highways have different driving speed requirements. Providing the best speed prompt for each lane can provide a more refined and reasonable driving speed for traffic in different lanes, avoiding the impact of excessive speed differences between different lanes.

[0022] Embodiment 2: like Figure 2 As shown, the present invention provides a tunnel safety prompt method based on real-time vehicle speed, based on the above-mentioned tunnel safety prompt system based on real-time vehicle speed, comprising the following steps: (1) The second vehicle speed detection device 4 obtains vehicle speed information and transmits the vehicle speed information to the second vehicle information processor 6. The second vehicle information processor 6 calculates the vehicle flow speed and the optimal tunnel entry speed and transmits the optimal tunnel entry speed to the vehicle speed information prompt screen 1. The vehicle speed information prompt screen 1 receives the optimal tunnel entry speed and displays it dynamically, thereby reducing the speed difference between each vehicle and the large front and rear acceleration of the vehicle, thereby reducing the occurrence of traffic accidents such as rear-end collisions in the tunnel; (2) The first vehicle speed detection device 2 detects the speed information of the vehicle that fails to change lanes in time, and transmits the speed information of the vehicle that fails to change lanes in time to the first vehicle information processor 7; (3) The first vehicle information processor 7 calculates the minimum lane change distance and the minimum braking distance, and transmits the minimum lane change distance and the minimum braking distance to the vehicle sensor 3; The specific formula for calculating the minimum lane change distance is as follows: S min = + + ; Where: is the visual recognition distance, that is, the distance the driver travels from seeing the light warning to understanding that there is a tunnel ahead and needs to change lanes. The calculation formula is: ; is the reaction distance, that is, the distance the driver turns on the turn signal and starts turning. The calculation formula is: ; is the distance traveled by the vehicle after entering the target lane, and the calculation formula is: ; In the formula, is the speed of the target vehicle; The visual recognition time from when the driver sees the light warning to when he understands that there is a tunnel ahead and needs to change lanes is 2.5 s. The time required for the driver to turn on the turn signal and start turning is 0.5 s; is the lane-changing time of the target vehicle, which is 3.0 s; is the running speed of the target vehicle when turning.

[0023] The specific formula for calculating the minimum braking distance is as follows: L= + ; Where: The distance from hearing the warning to understanding that there is a tunnel wall ahead and the driver must stop the car in time is calculated as follows: ; is the braking deceleration distance, that is, the distance the vehicle decelerates from its original speed to a stop. The calculation formula is: ; In the formula, is the speed of the target vehicle; The time from hearing the warning sound to understanding that there is a tunnel wall ahead and the vehicle must stop in time is 2.5 s. a To assume constant acceleration, take -8.5 ; (4) If the vehicle sensor 3 senses that the target vehicle has not changed lanes within the minimum lane change distance, the vehicle sensor 3 transmits a warning instruction to the lane change sound and light warning device 5, and then executes (5); If the vehicle sensor 3 senses that the target vehicle changes lanes within the minimum lane change distance, then (2) is executed again; (5) The lane change sound and light warning device 5 receives the warning instruction and issues a bright light warning of "please change lanes"; If the target vehicle still does not change lanes after receiving the light warning, when the target vehicle reaches the minimum braking distance, the lane change sound and light warning device 5 repeats the sound warning of "please brake immediately"; If the target vehicle changes lanes after receiving the bright light warning, execute (2) again; Preferably, the optimal entry speed is a value obtained by weighting and assigning 50% of the vehicle speed detected by the second group of vehicle speed detection equipment 4; Preferably, the lane change sound and light warning device 5 is composed of an LED lamp, which lights up red when an alarm is required and is normally closed.

[0024] After the present invention is implemented, the following effects can be produced: The complex terrain in the mountainous areas of my country makes it impossible to ensure the smoothness and safety of the highway lines during construction. Therefore, the lines at the entrances of some highway tunnels are dead-end roads. Under such lines, if there is fog, darkness or other poor lighting conditions, it is difficult for drivers to identify the road and they may fail to change lanes in time, resulting in scratches or even crashing into the tunnel wall. The tunnel safety prompt system for real-time speed detection provided by the present invention starts with the speed of the target vehicle itself, calculates the limit lane change distance and the limit braking distance, and has two levels of light prompts for lane change and sound prompts for emergency braking, which provides double protection for solving such traffic accidents. , which will effectively reduce the occurrence of such traffic accidents; at present, due to the particularity of tunnel driving and the variability of the black hole effect brought about by different sunlight, vehicles entering the tunnel are prone to rear-end collisions at the tunnel entrance due to excessive deceleration; the present invention starts with the real-time speed of vehicles entering the tunnel, and indirectly reflects the changes in the black hole effect of the tunnel. Through the variable speed information prompt screen 1, the real-time speed prompt is given to the vehicles about to enter the tunnel in different lanes, so that the vehicles enter the deceleration state in advance, and the traffic in each lane enters a relatively stable speed state, reducing the speed difference between vehicles, thereby effectively reducing the occurrence of rear-end collisions.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A tunnel safety prompt system based on real-time vehicle speed, characterized in that: include: A vehicle speed information prompting screen (1) provided outside the tunnel entrance is used to prompt the optimal speed for entering the tunnel; A first set of vehicle speed detection equipment (2) arranged on a detection bracket outside a tunnel entrance is used to detect speed information of vehicles that fail to change lanes in time and transmit the information to a first vehicle information processor (7); the first vehicle information processor (7) is arranged on a wall at the tunnel entrance and is used to calculate a minimum lane change distance and a minimum braking distance; The vehicle sensors (3) are arranged in sections on both sides of the road between the outside of the tunnel entrance and the tunnel entrance, and are used to receive the minimum lane change distance and the minimum braking distance transmitted by the first vehicle information processor (7); A second group of vehicle speed detection devices (4) are respectively arranged at a plurality of positions inside and outside the tunnel, and are used to obtain vehicle speed information and transmit it to a second vehicle information processor (6); the second vehicle information processor (6) is arranged on the wall of the tunnel entrance, and is used to calculate the vehicle flow speed and the optimal tunnel entry speed; A lane change sound and light warning device (5) arranged on the outer wall of the tunnel, used to warn the target vehicle to change lanes or emergency brake; The vehicle speed information prompt screen (1), the first set of vehicle speed detection equipment (2), the vehicle sensor (3), the second set of vehicle speed detection equipment (4), the lane change sound and light warning device (5), the second vehicle information processor (6) and the first vehicle information processor (7) are all equipped with wireless transmission equipment.

2. The tunnel safety prompt system based on real-time vehicle speed according to claim 1, characterized in that: The vehicle speed information prompt screen (1) is arranged 250 m outside the tunnel entrance; the first set of vehicle speed detection equipment (2) is arranged on a detection bracket 150 m outside the tunnel entrance; and the vehicle sensors (3) are arranged in sections on both sides of the road between 150 m outside the tunnel entrance and the tunnel entrance.

3. The tunnel safety prompt system based on real-time vehicle speed according to claim 1, characterized in that: The vehicle speed information prompt screen (1) is a variable information prompt screen, which automatically updates the optimal entry speed of vehicles entering the tunnel under the current sunlight conditions every 10 minutes.

4. A tunnel safety prompt system based on real-time vehicle speed according to claim 1, characterized in that: The content of the vehicle speed information prompt screen (1) is the lane-by-lane vehicle speed prompt.

5. The tunnel safety prompt system based on real-time vehicle speed according to claim 1, characterized in that: The second group of vehicle speed detection devices (4) are respectively arranged at four locations inside and outside the tunnel, specifically: the first vehicle speed detection device (4-1) is arranged 50 m outside the tunnel entrance, the second vehicle speed detection device (4-2) is arranged at the tunnel entrance, the third vehicle speed detection device (4-3) is arranged 100 m inside the tunnel entrance, and the fourth vehicle speed detection device (4-4) is arranged at the tunnel exit.

6. A tunnel safety prompt method based on real-time vehicle speed, based on a tunnel safety prompt system based on real-time vehicle speed according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, the second vehicle speed detection device (4) obtains vehicle speed information and transmits the vehicle speed information to the second vehicle information processor (6), the second vehicle information processor (6) calculates the vehicle flow speed and the optimal tunnel entry speed, and transmits the optimal tunnel entry speed to the vehicle speed information prompt screen (1), and the vehicle speed information prompt screen (1) receives the optimal tunnel entry speed and displays it; S2, the first group of vehicle speed detection devices (2) detects the speed information of the vehicle that fails to change lanes in time, and transmits the speed information of the vehicle that fails to change lanes in time to the first vehicle information processor (7); S3, the first vehicle information processor (7) calculates a minimum lane change distance and a minimum braking distance, and transmits the minimum lane change distance and the minimum braking distance to the vehicle sensor (3); S4, if the vehicle sensor (3) senses that the target vehicle has not changed lanes within the minimum lane change distance, the vehicle sensor (3) transmits a warning instruction to the lane change sound and light warning device (5), and then S5 is executed; If the vehicle sensor (3) senses that the target vehicle changes lanes within the minimum lane change distance, S2 is executed again; S5, the lane change sound and light warning device (5) receives the warning instruction and issues a warning.

7. A tunnel safety prompt method based on real-time vehicle speed according to claim 6, characterized in that: The optimal entry speed in S1 is a value obtained by weighting 50% of the vehicle speed detected by the second group of vehicle speed detection equipment (4) to obtain a value.

8. The tunnel safety prompt method based on real-time vehicle speed according to claim 6, characterized in that: The specific formula for calculating the minimum lane change distance in S3 is as follows: S min = + + ； Where: is the visual recognition distance, that is, the distance the driver travels from seeing the light warning to understanding that there is a tunnel ahead and needs to change lanes. The calculation formula is: ； is the reaction distance, that is, the distance the driver turns on the turn signal and starts turning. The calculation formula is: ； is the distance traveled by the vehicle after entering the target lane, and the calculation formula is: ； In the formula, is the speed of the target vehicle; The time it takes for the driver to see the light warning and understand that there is a tunnel ahead and that he needs to change lanes. The time required for the driver to turn on the turn signal and start turning; is the lane change time of the target vehicle; is the running speed of the target vehicle when turning.

9. The tunnel safety prompt method based on real-time vehicle speed according to claim 6, characterized in that: The specific formula for calculating the minimum braking distance in S3 is as follows: L= + ； Where: The distance from hearing the warning to understanding that there is a tunnel wall ahead and the driver must stop the car in time is calculated as follows: ； is the braking deceleration distance, that is, the distance the vehicle decelerates from its original speed to a stop. The calculation formula is: ； In the formula, is the speed of the target vehicle; The time from hearing the warning sound to realizing that there is a tunnel wall ahead and the vehicle must stop in time; a Assume constant acceleration.

10. The tunnel safety prompt method based on real-time vehicle speed according to claim 6, characterized in that: The S5 is specifically: The lane change sound and light warning device (5) receives the warning instruction and issues a bright light warning of "please change lanes"; If the target vehicle still does not change lanes after receiving the light warning, when the target vehicle reaches the minimum braking distance, the lane change sound and light warning device (5) repeats the sound warning of "Please brake immediately"; If the target vehicle changes lanes after receiving the bright light warning, S2 is executed again.

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