Vehicle-mounted tunnel lighting quality evaluation method

Abstract

According to the vehicle-mounted tunnel illumination quality evaluation method provided by the invention, the to-be-detected tunnel does not need to be stopped, the brightness value in the to-be-detected tunnel can be accurately estimated, and the brightness value is corrected based on the solid particulate matters in the air, so that the final brightness uniformity is determined; therefore, the illumination quality of the tunnel to be tested can be accurately evaluated, accurate operation and maintenance measures can be taken, and the operation safety of the tunnel is ensured.

Description

Technical Field

[0001] The invention relates to a tunnel lighting quality assessment method, and in particular to a vehicle-mounted tunnel lighting quality assessment method. Background Art

[0002] Tunnel lighting quality is one of the key factors for safe tunnel operation, which requires real-time evaluation and maintenance of tunnel lighting quality.

[0003] In the prior art, there are two main ways to evaluate lighting quality: the first is to measure the road illuminance on site and then convert it into road brightness according to an empirical formula. This method has the following problems: ① It requires traffic interruption, which affects the normal operation of highway tunnels and poses a great safety risk; ② The conversion relationship between illuminance and brightness is uncertain, which leads to overestimation and underestimation of the tunnel road brightness, and thus the true brightness of the tunnel road cannot be correctly grasped; ③ It is impossible to detect the brightness of areas such as tunnel walls and ceilings; ④ It is necessary to measure the grid points on the road one by one, which is slow, time-consuming and costly. The second is to use an imaging luminance meter to directly measure the brightness. This method has the following defects: ① Because the imaging luminance meter must be stationary during the measurement process and the imaging speed is slow, like the mode of converting illuminance to brightness, it also requires traffic interruption, which affects the normal operation of highway tunnels; ② The operation steps of the imaging luminance meter are complicated and need to be used in conjunction with a computer program at the measurement site, and the measurement efficiency is low.

[0004] Therefore, in order to solve the above technical problems, it is urgent to propose a new technical means. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a vehicle-mounted tunnel lighting quality assessment method, which does not require the tunnel to be tested to be shut down, and can accurately estimate the brightness value in the tunnel to be tested, and correct the brightness value based on solid particles in the air, so as to determine the final brightness uniformity, thereby being able to accurately assess the lighting quality of the tunnel to be tested, which is conducive to making accurate operation and maintenance measures to ensure the safe operation of the tunnel.

[0006] The present invention provides a vehicle-mounted tunnel lighting quality assessment method, comprising the following steps:

[0007] S1. In a laboratory environment, control the standard light source to work according to the set lighting brightness in the simulated tunnel, and record the concentration and density information of solid particles in the air under the current experimental environment;

[0008] S2. Use an imaging luminance meter to detect the luminance value of each monitoring point on the road surface in the simulated tunnel;

[0009] S3. Using a camera to set a speed in the simulated tunnel and obtain image information of each monitoring point on the road surface in the simulated tunnel;

[0010] S4. extracting the gray value of the simulated tunnel image;

[0011] S5. Repeat steps S2-S4 n times, and fit the brightness value and gray value to form a brightness-gray curve: Li = f(r i ); where: Li represents brightness, r i represents the gray value of the image, and f(·) represents the functional relationship between brightness and gray;

[0012] S6. A camera is installed on the measuring vehicle, and the measuring vehicle is moved in the tunnel to be measured at a set speed. The camera obtains image information of the road surface of the tunnel to be measured, and records the concentration and density information of air particles in the tunnel to be measured;

[0013] S7. Extract the gray value in the road surface image of the tunnel to be tested, and substitute the gray value into the brightness-grayscale curve to obtain the brightness value of the tunnel to be tested, and correct the brightness value based on the concentration and density of solid particles in the air;

[0014] S8. Determine the lighting quality of the tunnel to be tested based on the corrected brightness value.

[0015] Further, in step S8, judging the lighting quality of the tunnel to be measured based on the corrected brightness value specifically includes:

[0016] Determine the average value Li of the corrected brightness value ea :

[0017] Li' j Represents the corrected value of the brightness value after calculation of the jth image;

[0018] Calculate brightness uniformity UN:

[0019]

[0020] Among them: Li max Indicates the corrected maximum brightness value, Li min Indicates the corrected minimum brightness value;

[0021] The lighting quality of the tunnel to be tested is evaluated based on the brightness uniformity.

[0022] Furthermore, the brightness value is corrected based on the concentration and density of solid particles in the air, specifically including:

[0023] Determine the ratio of the concentration and density of solid particles in the air in the tunnel to be tested to the concentration and density of solid particles in the air in the laboratory environment:

[0024]

[0025] Where: k 1 Indicates the ratio of the concentration of solid particles in the air, k 2 Indicates the ratio of the density of solid particles in the air, C tar is the concentration of solid particles in the air of the tunnel to be tested, C bas Represents the concentration of solid particles in laboratory environment, r tar represents the density of solid particles in the air in the tunnel to be tested, r bas Indicates the concentration of solid particles in the air under laboratory conditions;

[0026] When k 1 Greater than or equal to the set threshold Y 1 or k 2 Greater than or equal to the set threshold Y 2 When , the detection data of the current tunnel to be tested is abandoned;

[0027] When k 1 <Y 1 And k 2 <Y 2 , the brightness value is revised by the following formula:

[0028] Among them, Li j represents the brightness value calculated from the grayscale value of the jth image before correction, δ 1 is the influencing factor of solid particle concentration, δ 2 is the influencing factor of solid particle density.

[0029] Furthermore, the set speed in step S3 and step S6 is the design vehicle speed of the tunnel to be tested.

[0030] Furthermore, the models and pixels of the cameras in the laboratory environment and the tunnel to be tested are the same.

[0031] Furthermore, the side wall reflection coefficients of the simulated tunnel and the tunnel to be tested are the same.

[0032] The beneficial effects of the present invention are as follows: through the present invention, there is no need to shut down the tunnel to be tested, and the brightness value in the tunnel to be tested can be accurately estimated, and the brightness value can be corrected based on the solid particles in the air to determine the final brightness uniformity, so that the lighting quality of the tunnel to be tested can be accurately evaluated, which is conducive to making accurate operation and maintenance measures to ensure the safe operation of the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0034] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below:

[0036] The present invention provides a vehicle-mounted tunnel lighting quality assessment method, comprising the following steps:

[0037] S1. In a laboratory environment, control the standard light source to work according to the set lighting brightness in the simulated tunnel, and record the concentration and density information of solid particles in the air under the current experimental environment;

[0038] S2. Use an imaging luminance meter to detect the luminance value of each monitoring point on the road surface in the simulated tunnel;

[0039] S3. Using a camera to set a speed in the simulated tunnel and obtain image information of each monitoring point on the road surface in the simulated tunnel;

[0040] S4. extracting the gray value of the simulated tunnel image;

[0041] S5. Repeat steps S2-S4 n times, and fit the brightness value and gray value to form a brightness-gray curve: Li = f(r i ); where: Li represents brightness, r i represents the gray value of the image, and f(·) represents the functional relationship between brightness and gray. Curve fitting is implemented using existing software, such as MATLAB software, which will not be described in detail here.

[0042] S6. A camera is installed on the measuring vehicle, and the measuring vehicle is moved in the tunnel to be measured at a set speed. The camera obtains image information of the road surface of the tunnel to be measured, and records the concentration and density information of air particles in the tunnel to be measured;

[0043] S7. Extract the gray value in the road surface image of the tunnel to be tested, and substitute the gray value into the brightness-grayscale curve to obtain the brightness value of the tunnel to be tested, and correct the brightness value based on the concentration and density of solid particles in the air;

[0044] S8. The lighting quality of the tunnel to be tested is judged based on the corrected brightness value. Through the above method, the tunnel to be tested does not need to be shut down, and the brightness value in the tunnel to be tested can be accurately estimated, and the brightness value is corrected based on the solid particles in the air to determine the final brightness uniformity, so that the lighting quality of the tunnel to be tested can be accurately evaluated, which is conducive to making accurate operation and maintenance measures to ensure the safe operation of the tunnel.

[0045] In this embodiment, in step S8, judging the lighting quality of the tunnel to be measured based on the corrected brightness value specifically includes:

[0046] Determine the average value Li of the corrected brightness value ea :

[0047] Li' j Represents the corrected value of the brightness value after calculation of the jth image;

[0048] Calculate brightness uniformity UN:

[0049]

[0050] Among them: Li max Indicates the corrected maximum brightness value, Li min Indicates the corrected minimum brightness value;

[0051] The lighting quality of the tunnel to be tested is evaluated according to the brightness uniformity, wherein the closer the brightness uniformity is to 1, the better the uniformity. For example, the brightness uniformity is divided into 3 levels. When the brightness uniformity is greater than the first threshold, it is the first level, indicating that the current lighting quality is good and no corresponding measures are required. When the brightness uniformity is greater than or equal to the second threshold and less than or equal to the first threshold, it is the second level, and the lighting fixtures need to be cleaned. When the brightness uniformity is less than the second threshold, it is the third level, indicating that the lamps need to be replaced and maintained, such as replacing the lamps at the monitoring points where the brightness value is less than the set value.

[0052] In this embodiment, the brightness value is corrected based on the concentration and density of solid particles in the air, specifically including:

[0053] Determine the ratio of the concentration and density of solid particles in the air in the tunnel to be tested to the concentration and density of solid particles in the air in the laboratory environment:

[0054]

[0055] Where: k 1 Indicates the ratio of the concentration of solid particles in the air, k 2 Indicates the ratio of the density of solid particles in the air, C tar is the concentration of solid particles in the air of the tunnel to be tested, C bas Represents the concentration of solid particles in laboratory environment, r tar represents the density of solid particles in the air in the tunnel to be tested, r bas Indicates the concentration of solid particles in the air under laboratory conditions;

[0056] When k 1 Greater than or equal to the set threshold Y1 or k 2 Greater than or equal to the set threshold Y 2 When , the detection data of the current tunnel to be tested is abandoned;

[0057] When k 1 <Y 1 And k 2 <Y 2 , the brightness value is revised by the following formula:

[0058] Among them, Li j represents the brightness value calculated from the grayscale value of the jth image before correction, δ 1 is the influencing factor of solid particle concentration, δ 2 is the influencing factor of solid particle density; in fact, the concentration of air particles in the laboratory environment is smaller than the concentration of solid particles in the actual tunnel to be tested. If it is directly calculated and determined, the brightness value in the tunnel to be tested is smaller than the actual value, thus affecting the evaluation result. In the above, the influence of the concentration and density of solid particles in the air on tunnel lighting is taken into account, so that the final evaluation result can be accurately determined. The concentration and density of solid particles are measured by existing particle concentration sensors and particle density sensors.

[0059] In this embodiment, the set speed in step S3 and step S6 is the design vehicle speed of the tunnel to be tested. In this way, the accuracy of the final result can be ensured.

[0060] In this embodiment, the models and pixels of the cameras in the laboratory environment and the tunnel to be tested are the same. In this way, the accuracy of the final result can be ensured.

[0061] In this embodiment, the side wall reflection coefficients of the simulated tunnel and the tunnel to be tested are the same, which can ensure the accuracy of the final result.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A vehicle-mounted tunnel lighting quality assessment method, characterized in that: The following steps are involved: S1. In a laboratory environment, control the standard light source to work according to the set lighting brightness in a simulated tunnel, and record the concentration and density information of solid particles in the air under the current experimental environment; S2. Use an imaging luminance meter to detect the luminance value of each monitoring point on the road surface in the simulated tunnel; S3. Using a camera to set a speed in the simulated tunnel and obtain image information of each monitoring point on the road surface in the simulated tunnel; S4. Extracting the gray value of the simulated tunnel image; S5. Repeat steps S2-S4 n times, and fit the brightness value and gray value to form a brightness-gray curve: Li = f(r i ); where: Li represents brightness, r i represents the gray value of the image, and f(·) represents the functional relationship between brightness and gray; S6. A camera is installed on the measuring vehicle, and the measuring vehicle is moved in the tunnel to be measured at a set speed. The camera obtains image information of the road surface of the tunnel to be measured, and records the concentration and density information of air particles in the tunnel to be measured; S7. Extract the gray value in the road surface image of the tunnel to be tested, and substitute the gray value into the brightness-grayscale curve to obtain the brightness value of the tunnel to be tested, and correct the brightness value based on the concentration and density of solid particles in the air; S8. Determine the lighting quality of the tunnel to be tested based on the corrected brightness value.

2. The vehicle-mounted tunnel lighting quality assessment method according to claim 1, characterized in that: In step S8, judging the lighting quality of the tunnel to be measured based on the corrected brightness value specifically includes: Determine the average value Li of the corrected brightness value ea : Li' j Represents the corrected value of the brightness value after calculation of the jth image; Calculate brightness uniformity UN: Among them: Li max Indicates the corrected maximum brightness value, Li min Indicates the corrected minimum brightness value; The lighting quality of the tunnel to be tested is evaluated based on the brightness uniformity.

3. The vehicle-mounted tunnel lighting quality assessment method according to claim 1, characterized in that: The brightness value is corrected based on the concentration and density of solid particles in the air, including: Determine the ratio of the concentration and density of solid particles in the air in the tunnel to be tested to the concentration and density of solid particles in the air in the laboratory environment: Where: k1 represents the ratio of the concentration of solid particles in the air, k2 represents the ratio of the density of solid particles in the air, C tar is the concentration of solid particles in the air of the tunnel to be tested, C bas Represents the concentration of solid particles in laboratory environment, r tar represents the density of solid particles in the air in the tunnel to be tested, r bas Indicates the concentration of solid particles in the air under laboratory conditions; When k1 is greater than or equal to the set threshold value Y1 or k2 is greater than or equal to the set threshold value Y2, the detection data of the current tunnel to be tested is abandoned; When k1<Y1 and k2<Y2, the brightness value is revised by the following formula: Among them, Li j represents the brightness value calculated from the grayscale value of the jth image before correction, δ1 is the solid particle concentration influence factor, and δ2 is the solid particle density influence factor.

4. The vehicle-mounted tunnel lighting quality assessment method according to claim 1, characterized in that: The set speed in step S3 and step S6 is the design vehicle speed of the tunnel to be tested.

5. The vehicle-mounted tunnel lighting quality assessment method according to claim 1, characterized in that: The cameras in the laboratory environment and the tunnel under test are of the same model and pixel.

6. The vehicle-mounted tunnel lighting quality assessment method according to claim 1, characterized in that: The side wall reflection coefficients of the simulated tunnel and the tunnel to be tested are the same.

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