Rainfall intensity-based divided lane speed limit early warning indication method and system

Abstract

The invention discloses a divided-lane speed-limiting early warning indication method based on rainfall intensity. The method comprises the following steps: collecting monitored rainfall in a red line domain of a speed-limiting road and calculating the rainfall intensity; calculating the road surface water film thickness of each lane based on the rainfall intensity value; calculating the safety critical vehicle speed of each lane based on the road surface water film thickness of each lane; and issuing a speed limit value of each lane based on the safety critical vehicle speed of each lane and an originally set speed limit value of the road, and issuing a corresponding lane warning mark based on the water film thickness of each lane. The invention further discloses a divided lane speed limiting early warning indication system based on the rainfall intensity. The system comprises a rainfall monitoring module, a critical vehicle speed calculation module and a judgment display module. Different speed limit information is issued for different lanes according to rainfall conditions in real time, the problems that rainfall weather factors are neglected in existing speed limit management and road speed limit is set to be a fixed value according to road grades are solved, and the safety and toughness of a road to cope with different rainfall weather are improved.

Description

Technical Field

[0001] This invention relates to the field of traffic early warning and control technology, and to a lane-specific speed limit warning indication method based on rainfall intensity, as well as a lane-specific speed limit warning indication system based on rainfall intensity. Background Technology

[0002] During highway operations, it was found that the accident rate is significantly higher in rainy weather compared to sunny weather, and both the accident rate and severity are affected by rainfall intensity and amount. The reason is that when rainfall intensity reaches a certain level, rainwater runoff on the road surface easily forms a water film. This film separates the tires from the road surface during driving, reducing tire adhesion and causing hydroplaning, which can lead to skidding and rollover accidents, affecting driving safety. Extensive meteorological data indicates that global warming continues, and extreme rainfall events are occurring frequently; therefore, improving road safety in rainy weather is an urgent problem that highway construction and operation must address.

[0003] Excessive speed is a major cause of hydroplaning on highways in rainy weather. High speeds prevent tires from effectively dispersing the water film from the road surface, significantly reducing the contact area between the vehicle and the road, ultimately leading to a complete loss of traction. Therefore, limiting vehicle speeds on highways in rainy conditions is an effective way to improve safety.

[0004] The design and operation speeds of existing highways do not comprehensively consider the impact of rainfall intensity and road surface water accumulation on driving safety, thus failing to adjust them according to weather conditions. Furthermore, highway speed limits are set as fixed values ​​based on road grade, and adjustments are made only along longitudinal road sections without differentiation by lane location. According to runoff theory, the thickness of the water film varies across different lanes, resulting in varying risks of hydroplaning when a uniform speed limit is applied. In conclusion, current speed limit measures are ineffective in reducing the safety risks of driving on highways in severe rainy weather. Summary of the Invention

[0005] In view of the prior art, the present invention provides a lane-specific speed limit warning indication method based on rainfall intensity, and also provides a lane-specific speed limit warning indication system based on rainfall intensity. To achieve the above objectives, the technical solution adopted by the present invention is as follows: A lane-specific speed limit warning method based on rainfall intensity includes the following steps: Step 1: Collect monitoring rainfall data and calculate rainfall intensity for the red line area of ​​the speed-limited highway; Step 2: Calculate the surface water film thickness for each lane based on the rainfall intensity value; Step 3: Calculate the safe critical speed for each lane based on the road surface water film thickness of each lane; Step 4: Based on the safe critical speed of each lane and the original speed limit value set by the highway, publish the speed limit value of each lane, and at the same time, publish the corresponding lane warning signs based on the thickness of the water film on the road surface of each lane.

[0006] The surface water film thickness of each lane is calculated based on the following formula: ; in, For the first Road surface water film thickness, For the number of lanes, It is half the width of the road. The road has a longitudinal slope. For the cross slope of the road, This refers to the intensity of rainfall.

[0007] The safe critical speed for each lane is calculated based on the following formula: ; in, For the first The safe critical speed for a lane For the first The thickness of the water film on the road surface of the lane.

[0008] The process of publishing speed limit values ​​for each lane based on the safe critical speed of each lane and the original speed limit value set by the highway includes the following steps: When the critical speed limit of a lane is greater than the speed limit set on the highway, the speed limit value for that lane is the speed limit set on the highway. When the critical speed limit of a lane is less than or equal to the speed limit set on the highway, the hundreds and tens digits of the speed limit value for that lane are the same as the hundreds and tens digits of the critical speed limit. When the units digit of the critical speed limit is 0 to 4, the units digit of the speed limit value for that lane is adjusted to 0. When the units digit of the critical speed limit is 5 to 9, the units digit of the speed limit value for that lane is adjusted to 5.

[0009] The process of issuing corresponding lane warning signs based on the water film thickness of each lane includes the following steps: When the water film thickness of a lane is less than or equal to 2.5 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in green text indicating "low risk". When the water film thickness of a lane is greater than 2.5 mm but less than or equal to 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in yellow text indicating "medium risk". When the water film thickness of a lane is greater than 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in red text indicating "high risk".

[0010] A lane-specific speed limit warning system based on rainfall intensity includes the following modules: Rainfall monitoring module: used to collect the monitored rainfall in the red line area of ​​the speed-limited highway and calculate the rainfall intensity, and send the rainfall and rainfall intensity to the critical speed calculation module; Critical speed calculation module: Calculates the surface water film thickness for each lane based on rainfall intensity, calculates the safe critical speed for each lane based on the surface water film thickness, and sends the result to the judgment and display module. The thickness of the surface water film for each lane is calculated based on the following formula: ; in, For the first Road surface water film thickness, For the number of lanes, It is half the width of the road. The road has a longitudinal slope. For the cross slope of the road, Rainfall intensity, The safe critical speed for each lane is calculated based on the following formula: ;in, For the first The safe critical speed for a lane For the first The thickness of the water film on the road surface of the lane; The judgment and display module: Based on the safe critical speed of each lane and the original speed limit value set by the highway, it publishes the lane speed limit value for each lane, and at the same time, it publishes the corresponding lane warning signs based on the road surface water film thickness for each lane. When the critical speed limit for a lane is greater than the highway's set speed limit, the published speed limit for that lane is the highway's set speed limit; when the critical speed limit for a lane is less than or equal to the highway's set speed limit, the speed limit for that lane is adjusted based on the critical speed limit for that lane. The adjustment of the speed limit value corresponding to a lane based on the lane's corresponding safe critical speed value includes the following steps: the hundreds and tens digits of the published speed limit value for the lane are the same as the hundreds and tens digits of the lane's safe critical speed; when the units digit of the lane's safe critical speed is 0-4, the units digit of the published speed limit value for the lane is adjusted to 0; when the units digit of the lane's safe critical speed is 5-9, the units digit of the published speed limit value for the lane is adjusted to 5. When the water film thickness of a lane is less than or equal to 2.5 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in green text indicating "low risk". When the water film thickness of a lane is greater than 2.5 mm but less than or equal to 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in yellow text indicating "medium risk". When the water film thickness of a lane is greater than 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in red text indicating "high risk".

[0011] A computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the above-described method for lane-specific speed limit warning based on rainfall intensity.

[0012] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method for lane-specific speed limit warning based on rainfall intensity.

[0013] A computer program product includes a computer program that, when executed by a processor, implements the steps of the above-described method for lane-specific speed limit warning based on rainfall intensity.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention monitors the rainfall intensity in the road area in real time and calculates the surface water film thickness of each lane based on the rainfall intensity and road alignment data (half-width of the road surface, longitudinal slope and cross slope of the road); and calculates the safe critical speed of each lane based on the surface water film thickness of each lane, thereby realizing lane-specific speed limit warning.

[0015] 2. The display module determines the speed limit values ​​for each lane and the corresponding lane warning signs for each lane, and then sends these values ​​to drivers on the road to provide speed limit reminders and warnings.

[0016] 3. This invention proposes corresponding speed limits for different lanes in real time based on rainfall conditions, overcoming the problems of existing speed limit management ignoring rainfall weather factors and setting fixed values ​​for highway speed limits based on road grade. This improves the safety resilience of highways in response to different rainfall weather conditions and enhances driving safety in rainy weather. Attached Figure Description

[0017] Figure 1 This is a flowchart of a lane-specific speed limit warning method based on rainfall intensity; Figure 2 This is a schematic diagram of a lane-specific speed limit warning system based on rainfall intensity. Detailed Implementation

[0018] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to implementation examples. It should be understood that the implementation examples described herein are for illustration and explanation only and are not intended to limit the present invention.

[0019] Example 1: like Figure 1 and Figure 2 As shown, a lane-specific speed limit warning method based on rainfall intensity includes the following steps: Step 1: Collect monitoring rainfall data and calculate rainfall intensity for the red line area of ​​the speed-limited highway; Within the red line area of ​​the speed-limited highway, rainfall is collected and monitored in real time, and rainfall intensity is calculated. In this embodiment, the monitoring and calculation frequency is 10 minutes per instance. Monitoring rainfall and calculating rainfall intensity is existing technology and will not be described in detail.

[0020] Step 2: Calculate the surface water film thickness for each lane based on rainfall intensity; The thickness of the surface water film for each lane is calculated based on the following formula: ; in, For the first Road surface water film thickness (mm). For the number of lanes, The width of half the road surface (m) The longitudinal slope of the road (%) The cross slope of the road (%) Rainfall intensity (mm / h).

[0021] Data on half-width road surface, longitudinal slope, and cross slope are obtained from the construction or operation unit based on the monitoring location.

[0022] when At that time, the first lane is the lane on the top side of the cross slope of half of the road surface. The second lane is the lane adjacent to the first lane along the road's cross slope, and so on. The maximum value is the total number of lanes on half of the road surface.

[0023] Step 3: Calculate the safe critical speed for each lane based on the road surface water film thickness of each lane; The safe critical speed for each lane is calculated based on the following formula: ;in, For the first The safe critical speed for a lane The unit is km / h.

[0024] Step 4: Based on the safe critical speed of each lane and the original speed limit value set by the highway, publish the speed limit value of each lane, and at the same time, publish the corresponding lane warning signs based on the thickness of the water film on the road surface of each lane. When publishing speed limits for each lane, it is necessary to compare the critical safe speed of each lane with the original speed limit set for the highway. When the critical safe speed of a lane is greater than the original speed limit set for the highway, the published speed limit for that lane is the original speed limit set for the highway; when the critical safe speed of a lane is less than or equal to the original speed limit set for the highway, the speed limit for that lane is adjusted based on the critical safe speed of that lane.

[0025] Specifically, when adjusting the speed limit for a lane based on its corresponding critical safety speed, the hundreds and tens digits of the published speed limit are the same as the hundreds and tens digits of the lane's critical safety speed. When the units digit of the lane's critical safety speed is 0-4, the units digit of the published speed limit is adjusted to 0; when the units digit of the lane's critical safety speed is 5-9, the units digit of the published speed limit is adjusted to 5. These adjustments ensure that the published speed limit for each lane is less than or equal to the corresponding lane's critical safety speed, thus reducing the occurrence of accidents.

[0026] like Figure 2 As shown, displaying the corresponding lane warning sign below each lane's speed limit while publishing the speed limit values ​​enhances visual alertness and reduces the risk of speeding for drivers.

[0027] Preferably, when the water film thickness of the lane is less than or equal to 2.5 mm, a corresponding lane warning sign is displayed below the speed limit value of the corresponding lane, and the lane warning sign is displayed in green text as "low risk"; when the water film thickness of the lane is greater than 2.5 mm and less than or equal to 4 mm, a corresponding lane warning sign is displayed below the speed limit value of the corresponding lane, and the lane warning sign is displayed in yellow text as "medium risk"; when the water film thickness of the lane is greater than 4 mm, a corresponding lane warning sign is displayed below the speed limit value of the corresponding lane, and the lane warning sign is displayed in red text as "high risk".

[0028] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods.

[0029] Example 2: In this embodiment, a lane-specific speed limit warning system based on rainfall intensity is also provided, including: Rainfall monitoring module: Used to collect the monitored rainfall in the red line area of ​​the speed-limited highway and calculate the rainfall intensity, and send the rainfall and rainfall intensity to the critical speed calculation module.

[0030] Critical speed calculation module: Calculates the surface water film thickness of each lane based on the rainfall intensity, calculates the safe critical speed of each lane based on the surface water film thickness of each lane, and sends it to the judgment and display module; The thickness of the surface water film for each lane is calculated based on the following formula: ; in, For the first Road surface water film thickness (mm). For the number of lanes, The width of half the road surface (m) The longitudinal slope of the road (%) The cross slope of the road (%) Rainfall intensity (mm / h).

[0031] The safe critical speed for each lane is calculated based on the following formula: ;in, For the first The safe critical speed (km / h) for a lane. For the first Thickness of water film on road surface (mm).

[0032] Judgment and display module: Based on the safe critical speed of each lane and the original speed limit value set by the highway, it publishes the speed limit value of each lane, and at the same time, it publishes the corresponding lane warning sign based on the thickness of the water film on the road surface of each lane. When the critical speed limit of a lane is greater than the speed limit set on the highway, the speed limit value for that lane is the speed limit set on the highway. When the critical speed limit of a lane is less than or equal to the speed limit set on the highway, the speed limit value for that lane is adjusted based on the critical speed limit value for that lane.

[0033] Adjusting the speed limit value corresponding to a lane based on the lane's corresponding safe critical speed value includes the following steps: the hundreds and tens digits of the published speed limit value for the lane are the same as the hundreds and tens digits of the lane's safe critical speed. When the units digit of the lane's safe critical speed is 0 to 4, the units digit of the published speed limit value for the lane is adjusted to 0; when the units digit of the lane's safe critical speed is 5 to 9, the units digit of the published speed limit value for the lane is adjusted to 5.

[0034] When the water film thickness of a lane is less than or equal to 2.5 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in green text indicating "low risk". When the water film thickness of a lane is greater than 2.5 mm but less than or equal to 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in yellow text indicating "medium risk". When the water film thickness of a lane is greater than 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in red text indicating "high risk".

[0035] Example 3: The following example, taking a 200m section of an accident-prone area on a two-way eight-lane highway, will be used to further illustrate the lane-specific speed limit warning system described in Example 2.

[0036] The rainfall monitoring module is installed on the outside of the hard shoulder guardrail of the highway; The critical speed calculation module is installed on the gantry in the middle of the road; The judgment and display module is also set on the gantry in the middle of the road. The judgment and display module publishes the speed limit value of each lane and the corresponding lane warning sign for each lane. Each lane corresponds to one judgment and display module, or all lanes in the same direction can share one judgment and display module. When sharing one judgment and display module, the judgment and display module has 4 display columns, and the display columns are set one-to-one with the lanes.

[0037] The rainfall monitoring module collects and monitors rainfall and calculates the rainfall intensity as 45 mm / h.

[0038] The surface water film thickness of each lane calculated by the critical speed calculation module is shown in Table 1. When calculating the surface water film thickness of each lane, the half-width of the road is 20m, the longitudinal slope of the road is 0.3%, and the cross slope of the road is 1.5%.

[0039] Table 1. Surface water film thickness for each lane The critical speeds for each lane calculated by the critical speed calculation module are shown in Table 2.

[0040] Table 2 Safety Critical Speed ​​Table for Each Lane The speed limit values ​​corresponding to the lanes displayed by the judgment module are shown in Table 3. The speed limit value set for the highway is 100km / h.

[0041] Table 3 Speed ​​Limit Values ​​for Each Lane The lane warning signs corresponding to each lane displayed by the module are shown in Table 4.

[0042] Table 4. Lane Warning Signs for Each Lane The judgment and display module publishes the lane speed limit values ​​for each lane to drivers on the road. Drivers can reduce the risk of vehicle accidents by limiting their speed, while lane warning signs indicate the risk situation and remind drivers to drive cautiously.

[0043] Example 4: In this embodiment, a computer device is also provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0044] Example 5: In this embodiment, a computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the steps in the above-described method embodiments.

[0045] Example 6: In this embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0046] It should be noted that the embodiments described in this invention are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for lane-specific speed limit warning indication based on rainfall intensity, characterized in that, Includes the following steps: Step 1: Collect monitoring rainfall data and calculate rainfall intensity for the red line area of ​​the speed-limited highway; Step 2: Calculate the surface water film thickness for each lane based on the rainfall intensity value; Step 3: Calculate the safe critical speed for each lane based on the road surface water film thickness of each lane; Step 4: Based on the safe critical speed of each lane and the original speed limit value set by the highway, publish the speed limit value of each lane, and at the same time, publish the corresponding lane warning signs based on the thickness of the water film on the road surface of each lane.

2. The method for lane-specific speed limit warning based on rainfall intensity according to claim 1, characterized in that, The surface water film thickness of each lane is calculated based on the following formula: ； in, For the first Road surface water film thickness, For the number of lanes, It is half the width of the road. The road has a longitudinal slope. For the cross slope of the road, This refers to the intensity of rainfall.

3. The method for lane-specific speed limit warning indication based on rainfall intensity according to claim 2, characterized in that, The safe critical speed for each lane is calculated based on the following formula: ； in, For the first The safe critical speed for a lane For the first The thickness of the water film on the road surface of the lane.

4. The method for lane-specific speed limit warning based on rainfall intensity according to claim 3, characterized in that, The process of publishing speed limit values ​​for each lane based on the safe critical speed of each lane and the original speed limit value set by the highway includes the following steps: When the critical speed limit of a lane is greater than the speed limit set on the highway, the speed limit value for that lane is the speed limit set on the highway. When the critical speed limit of a lane is less than or equal to the speed limit set on the highway, the hundreds and tens digits of the speed limit value for that lane are the same as the hundreds and tens digits of the critical speed limit. When the units digit of the critical speed limit is 0 to 4, the units digit of the speed limit value for that lane is adjusted to 0. When the units digit of the critical speed limit is 5 to 9, the units digit of the speed limit value for that lane is adjusted to 5.

5. The method for lane-specific speed limit warning indication based on rainfall intensity according to claim 3, characterized in that, The process of issuing corresponding lane warning signs based on the water film thickness of each lane includes the following steps: When the water film thickness of a lane is less than or equal to 2.5 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in green text indicating "low risk". When the water film thickness of a lane is greater than 2.5 mm but less than or equal to 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in yellow text indicating "medium risk". When the water film thickness of a lane is greater than 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in red text indicating "high risk".

6. A lane-specific speed limit warning and indication system based on rainfall intensity, characterized in that, Includes the following modules: Rainfall monitoring module: used to collect the monitored rainfall in the red line area of ​​the speed-limited highway and calculate the rainfall intensity, and send the rainfall and rainfall intensity to the critical speed calculation module; Critical speed calculation module: Calculates the surface water film thickness for each lane based on rainfall intensity, calculates the safe critical speed for each lane based on the surface water film thickness, and sends the result to the judgment and display module. The thickness of the surface water film for each lane is calculated based on the following formula: ； in, For the first Road surface water film thickness, For the number of lanes, It is half the width of the road. The road has a longitudinal slope. For the cross slope of the road, Rainfall intensity, The safe critical speed for each lane is calculated based on the following formula: ;in, For the first The safe critical speed for a lane For the first The thickness of the water film on the road surface of the lane; The judgment and display module: Based on the safe critical speed of each lane and the original speed limit value set by the highway, it publishes the lane speed limit value for each lane, and at the same time, it publishes the corresponding lane warning signs based on the road surface water film thickness for each lane. When the critical speed limit for a lane is greater than the highway's set speed limit, the published speed limit for that lane is the highway's set speed limit; when the critical speed limit for a lane is less than or equal to the highway's set speed limit, the speed limit for that lane is adjusted based on the critical speed limit for that lane. Adjusting the speed limit for a lane based on its corresponding safe critical speed value involves the following steps: The hundreds and tens digits of the published speed limit for the lane are the same as the hundreds and tens digits of the lane's safe critical speed. When the units digit of the lane's safe critical speed is 0-4, the units digit of the published speed limit for the lane is adjusted to 0; when the units digit of the lane's safe critical speed is 5-9, the units digit of the published speed limit for the lane is adjusted to 5. When the water film thickness of a lane is less than or equal to 2.5 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in green text indicating "low risk". When the water film thickness of a lane is greater than 2.5 mm but less than or equal to 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in yellow text indicating "medium risk". When the water film thickness of a lane is greater than 4 mm, a corresponding lane warning sign will be displayed below the speed limit value for that lane, and the lane warning sign will be displayed in red text indicating "high risk".

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the lane-specific speed limit warning indication method based on rainfall intensity as described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the lane-specific speed limit warning indication method based on rainfall intensity as described in any one of claims 1 to 5.

9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the lane-specific speed limit warning indication method based on rainfall intensity as described in any one of claims 1 to 5.

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