Road sign retroreflection coefficient detection method, device, equipment, system and medium

Abstract

The present application relates to a method, device, equipment, system and medium for detecting the retroreflection coefficient of road signs, which is applied to the field of safety detection technology. The method includes: obtaining the position of the retroreflection coefficient detection equipment and establishing a rectangular coordinate system based on the position; obtaining image information of the target to be detected and determining the center point of the target to be detected; determining the retroreflection body axis, reference axis, observation axis and illumination body axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected; calculating the angle of the current observation angle and the angle of the current incident angle; judging whether the current angle is consistent with the preset angle; if not, establishing a local coordinate system; obtaining the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, calculating the posture adjustment angle; adjusting the posture of the retroreflection coefficient detection equipment based on the posture adjustment angle, and measuring the retroreflection coefficient of the target to be detected based on the adjusted posture. The present application has the effect of safely and efficiently detecting the retroreflection coefficient of road signs.

Description

Technical Field

[0001] The present application relates to the technical field of safety monitoring, and in particular to a method, device, equipment, system and medium for detecting retroreflection coefficient of road signs. Background Art

[0002] Retroreflective materials are widely used in road signs such as traffic signs, markings, contour signs, vehicle reflective signs, motor vehicle license plates, etc. As an important infrastructure on highways, road signs play a very important role in ensuring traffic safety and improving the level of inherent safety.

[0003] Retroreflection coefficient is the most important technical indicator for testing various retroreflective materials. Therefore, strengthening the acceptance and maintenance of road signs to ensure that the retroreflection coefficient of road signs is within the standard range is the guarantee for the development and improvement of road traffic safety.

[0004] The current method for detecting the retroreflection coefficient of road signs is for workers to detect the road signs using handheld detection equipment. In addition, most road signs are located at high locations and require high-altitude equipment for detection. The detection process is labor-intensive, inefficient, and unsafe. Summary of the invention

[0005] In order to safely and efficiently detect the retroreflection coefficient of road signs, the present application provides a method, device, equipment, system and medium for detecting the retroreflection coefficient of road signs.

[0006] In a first aspect, the present application provides a method for detecting a retroreflection coefficient of a road sign, which adopts the following technical solution:

[0007] A method for detecting a road sign retroreflection coefficient, comprising:

[0008] Obtaining the position of the retroreflection coefficient detection device, and establishing a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device; obtaining image information of the target to be detected, and determining the center point of the target to be detected based on the image information;

[0009] Determine the retroreflector axis, reference axis, observation axis and illumination axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected; calculate the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, reference axis, observation axis and illumination axis; determine whether the angle of the current observation angle and the angle of the current incident angle are consistent with the angle of the preset observation angle and the angle of the preset incident angle;

[0010] If the angle of the current observation angle and the angle of the current incident angle are inconsistent with the angle of the preset observation angle and the angle of the preset incident angle, a local coordinate system is established based on the position of the retroreflection coefficient detection device;

[0011] Obtain the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculate the posture adjustment angle based on the transformation relationship;

[0012] The posture of the retroreflection coefficient detection device is adjusted based on the posture adjustment angle, and the retroreflection coefficient of the target to be detected is measured based on the adjusted posture.

[0013] By adopting the above technical scheme, during the acceptance, inspection and maintenance stage of road signs, i.e., targets to be detected, it is necessary to check and calculate the retroreflection coefficients of a large number of road signs. During the inspection, multiple axes for detecting the retroreflection coefficients are established according to the center points of the road signs, and a Cartesian rectangular coordinate system is established according to the positions of the retroreflection coefficient detection equipment to determine the observation angle and the incident angle under the current posture. When there is a difference between the angles of the preset observation angle and the incident angle, a local coordinate system is established, and the posture adjustment angle is calculated according to the transformation between the local coordinate system and the Cartesian rectangular coordinate system, so that the adjusted observation angle and incident angle are consistent with the preset observation angle and incident angle, thereby realizing accurate measurement and calculation of the retroreflection coefficient. The overall adjustment process does not require the participation of staff, so that the retroreflection coefficients of road signs can be detected safely and efficiently.

[0014] Optionally, the angle of the current observation angle and the angle of the current incident angle calculated based on the retroreflector axis, the reference axis, the observation axis, and the illumination axis include:

[0015] Obtaining the distance between the retroreflection coefficient detection device and the target to be detected;

[0016] Determine the space vectors of the retroreflector axis, the reference axis, the observation axis and the illumination axis in the Cartesian rectangular coordinate system based on the distance; calculate the angle of the current observation angle based on the space vector of the observation axis and the space vector of the illumination axis;

[0017] The angle of the current incident angle is calculated based on the space vector of the retroreflection body axis and the space vector of the illumination body axis.

[0018] Optionally, acquiring image information of the target to be detected, and determining the center point of the target to be detected based on the image information includes: acquiring the image geometry of the target to be detected, and calculating the center point of the target to be detected based on the image geometry.

[0019] Optionally, establishing a local coordinate system based on the position of the retroreflection coefficient detection device includes:

[0020] A local coordinate system of the current posture and a local coordinate system of the preset target posture are established on the basis of the Cartesian rectangular coordinate system of the retroreflection coefficient detection device.

[0021] Optionally, obtaining a transformation relationship between a local coordinate system and a Cartesian rectangular coordinate system, and calculating a posture adjustment angle based on the transformation relationship includes:

[0022] Obtain the Euler angles between the local coordinate system of the current posture and the local coordinate system of the preset target posture, and establish a rotation matrix based on the Euler angles and the transformation relationship;

[0023] Get the posture adjustment sequence and build the Euler transformation matrix based on the rotation matrix;

[0024] Determine the posture adjustment formula based on the Euler transformation matrix;

[0025] Calculate the attitude adjustment angle based on the attitude adjustment matrix.

[0026] Optionally, obtaining a position of a retroreflection coefficient detection device, and establishing a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device includes:

[0027] Obtaining the real-time relative distance between the vehicle equipped with the retroreflection coefficient detection device and the target to be detected, and determining whether the real-time relative distance reaches a preset distance range;

[0028] If the real-time relative distance reaches the preset distance range, a safe parking position is obtained and the car is parked at the safe parking position;

[0029] Acquire a safe parking position, and determine a position of a retroreflection coefficient detection device based on the safe parking position;

[0030] A Cartesian rectangular coordinate system is established based on the position of the retroreflection coefficient detection device.

[0031] In a second aspect, the present application provides a road sign retroreflection coefficient detection device, which adopts the following technical solution:

[0032] A road sign retroreflection coefficient detection device, comprising:

[0033] A position acquisition module, used to acquire the position of the retroreflection coefficient detection device and establish a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device;

[0034] A center confirmation module is used to obtain image information of the target to be detected and determine the center point of the target to be detected based on the image information; an axis determination module is used to determine the retroreflector axis, reference axis, observation axis and illumination axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected;

[0035] An angle calculation module, used for calculating the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis;

[0036] An angle determination module, used to determine whether the angle of the current observation angle and the angle of the current incident angle are consistent with the angle of the preset observation angle and the angle of the preset incident angle;

[0037] A coordinate establishment module, for establishing a local coordinate system based on the position of the retroreflection coefficient detection device if the angle of the current observation angle and the angle of the current incident angle are inconsistent with the angle of the preset observation angle and the angle of the preset incident angle;

[0038] The posture calculation module is used to obtain the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculate the posture adjustment angle based on the transformation relationship;

[0039] The device adjustment module is used to adjust the posture of the retroreflection coefficient detection device based on the posture adjustment angle, and measure the retroreflection coefficient of the target to be detected based on the adjusted posture.

[0040] By adopting the above technical scheme, during the acceptance, inspection and maintenance stage of road signs, i.e., targets to be detected, it is necessary to check and calculate the retroreflection coefficients of a large number of road signs. During the inspection, multiple axes for detecting the retroreflection coefficients are established according to the center points of the road signs, and a Cartesian rectangular coordinate system is established according to the positions of the retroreflection coefficient detection equipment to determine the observation angle and the incident angle under the current posture. When there is a difference between the angles of the preset observation angle and the incident angle, a local coordinate system is established, and the posture adjustment angle is calculated according to the transformation between the local coordinate system and the Cartesian rectangular coordinate system, so that the adjusted observation angle and incident angle are consistent with the preset observation angle and incident angle, thereby realizing accurate measurement and calculation of the retroreflection coefficient. The overall adjustment process does not require the participation of staff, so that the retroreflection coefficients of road signs can be detected safely and efficiently.

[0041] In a third aspect, the present application provides an electronic device, which adopts the following technical solution:

[0042] An electronic device comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executes the road sign retroreflection coefficient detection method described in any one of the first aspects.

[0043] In a fourth aspect, the present application provides a road sign retroreflection coefficient detection system, which adopts the following technical solution: a road sign retroreflection coefficient detection system, including a vehicle-mounted retroreflection coefficient detection device, a distance sensor, an image acquisition device, and the electronic device as described in the third aspect;

[0044] The retroreflection coefficient detection device is used to detect the retroreflection coefficient of the device to be detected, and send the retroreflection coefficient to the electronic device;

[0045] The distance sensor is used to detect the distance between the retroreflection coefficient detection device and the target to be detected, and send the distance to the electronic device;

[0046] The image acquisition device is used to acquire image information of the target to be detected and send the image information to the electronic device.

[0047] In a fifth aspect, the present application provides a computer-readable storage medium, which adopts the following technical solution:

[0048] A computer-readable storage medium stores a computer program that can be loaded by a processor and execute the road sign retroreflection coefficient detection method described in any one of the first aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a flow chart of a method for detecting retroreflection coefficient of road signs provided in an embodiment of the present application.

[0050] Figure 2 It is a structural block diagram of the detection device and the target to be detected provided in the embodiment of the present application.

[0051] Figure 3 It is a structural block diagram of the Cartesian rectangular coordinate system provided in an embodiment of the present application.

[0052] Figure 4 It is a structural block diagram of the local coordinate system provided in an embodiment of the present application.

[0053] Figure 5 It is a structural block diagram of a road sign retroreflection coefficient detection device provided in an embodiment of the present application.

[0054] Figure 6 It is a structural block diagram of an electronic device provided in an embodiment of the present application.

[0055] Figure 7 It is a structural block diagram of a road sign retroreflection coefficient detection system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] The present application is further described in detail below in conjunction with the accompanying drawings.

[0057] Figure 1 A schematic flow chart of a method for detecting retroreflection coefficient of road signs provided in an embodiment of the present application.

[0058] like Figure 1 As shown, the main process of the method is described as follows (steps S101 to S108):

[0059] In this embodiment, in addition to the retroreflection coefficient detection device, a distance sensor and an image acquisition device are also provided. The distance sensor can be a laser rangefinder, and the image acquisition device can be an industrial camera. It should be noted that the specific distance sensor and image acquisition device need to be set according to actual needs. It is only necessary to achieve the effect of distance measurement and image acquisition, and no specific limitation is made here.

[0060] Step S101, obtaining the position of the retroreflection coefficient detection device, and establishing a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device.

[0061] For step S101, the real-time relative distance between the vehicle equipped with the retroreflection coefficient detection device and the target to be detected is obtained, and it is determined whether the real-time relative distance reaches the preset distance range; if the real-time relative distance reaches the preset distance range, a safe parking position is obtained and the vehicle is parked at the safe parking position; the safe parking position is obtained, and the position of the retroreflection coefficient detection device is determined based on the safe parking position; a Cartesian rectangular coordinate system is established based on the position of the retroreflection coefficient detection device.

[0062] In this embodiment, the distance sensor detects in real time the relative distance between a vehicle equipped with a retroreflection coefficient detection device and a target to be detected. When the distance between the retroreflection coefficient detection device and the target to be detected reaches within a preset distance range, a safe position within the distance range is selected for parking, and the actual distance between the parking position and the target to be detected is obtained, and a spatial rectangular coordinate system is established based on the actual distance of the retroreflection coefficient detection device.

[0063] The spatial rectangular coordinate system is established using the Cartesian rectangular coordinate system. The retroreflection coefficient detection equipment includes a receiver and a projection light source. In order to ensure that the area and brightness of the projection light source projected onto the target to be detected are within the range that can be measured and received by the receiver, the distance range is set between 50 meters and 35 meters.

[0064] Step S102: acquiring image information of the target to be detected, and determining the center point of the target to be detected based on the image information.

[0065] With respect to step S102 , the image geometry of the target to be detected is obtained, and the center point of the target to be detected is calculated based on the image geometry.

[0066] In this embodiment, the image information includes image color information and image geometry of the target to be detected. The image color information is used to calculate the retroreflection coefficient, and the image geometry is used to calculate the center point of the target to be detected.

[0067] Road signs, i.e., targets to be detected, come in a variety of shapes and sizes. The most common geometric shapes of targets to be detected are axisymmetric figures such as squares, rectangles, and circles. When the target to be detected is an axisymmetric figure, the center point is determined based on the intersection of at least two axes of symmetry of the axisymmetric figure. However, when the target to be detected is not an axisymmetric figure, the center of gravity of the figure is calculated and the center of gravity is used as the center point.

[0068] Step S103, determining the retroreflective body axis, the reference axis, the observation axis and the illumination body axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected.

[0069] Step S104, calculating the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis;

[0070] For step S104, the distance between the retroreflection coefficient detection device and the target to be detected is obtained; based on the distance, the spatial vectors of the retroreflector axis, the reference axis, the observation axis and the illumination body axis in the Cartesian rectangular coordinate system are determined; based on the spatial vector of the observation axis and the spatial vector of the illumination body axis, the angle of the current observation angle is calculated; based on the spatial vector of the retroreflector axis and the spatial vector of the illumination body axis, the angle of the current incident angle is calculated.

[0071] In this embodiment, according to the testing principle of the retroreflection coefficient, the spatial points in the Cartesian rectangular coordinate system can be converted into vector relationships. For the sake of control variables and modeling considerations, in the established road detection model, the targets to be detected are all in ideal states. In the Cartesian rectangular coordinate system of the retroreflection coefficient dynamic test, it is assumed that the retroreflector axis of the target to be detected can establish a vertical or parallel relationship with one or more coordinate axes. The reference axis passes through the retroreflector surface and is perpendicular to the plane where the road surface is located, which is used to locate the object to be tested in the xy plane. The illumination axis is emitted by the projection light source and points to the center point of the target to be detected. The height of the projection light source is relatively fixed in the test system. The observation axis is emitted by the receiver of the retroreflection coefficient test and points to the retroreflector to be tested. Thus, the following four vectors of the retroreflection test space are obtained to generate a retroreflection test space vector table.

[0072] The vector table of the retroreflection test space is as follows:

[0073] Table 1 Retroreflection test space vector table

[0074] Serial number name definition vector 1 Retroreflective body axis Normal vector perpendicular to the retroreflector surface R 2 Reference axis Derived from the axes of the retroreflectors, perpendicular to each other D 3 Observation axis Emitted by the receiver, directed toward the retroreflector E 4 lighting body axis Emitted by the projected light source, directed toward the retroreflector I

[0075] Figure 2 It is a structural block diagram of the detection device and the target to be detected provided in the embodiment of the present application.

[0076] like Figure 2As shown, the angle between the retroreflector axis and the illuminating body axis is the incident angle, denoted by β, and the angle between the illuminating body axis and the observing axis is the observing angle, denoted by α. In this embodiment, the absolute value of the preset angle of the incident angle β is 4 degrees, and the absolute value of the preset angle of the observing angle α is 0.2 degrees.

[0077] In this embodiment, the angle is calculated using a 180-degree measurement method. The incident angle may be negative. Therefore, in order to eliminate the impact of a negative incident angle on the calculation, the absolute value of the incident angle is set to 4 degrees.

[0078] Figure 3 It is a structural block diagram of the Cartesian rectangular coordinate system provided in an embodiment of the present application.

[0079] like Figure 3 As shown, the overall coordinate system is the basis of the test geometry system. The Cartesian rectangular coordinate system is used to establish a mathematical model that associates points in space with ordered arrays. Combined with the road detection scene, the overall coordinate system for the dynamic test of the retroreflection system is established as follows. The origin of the coordinate system is the projection point of the test equipment on the road surface, set as point O, and the plane where the road is located is the xy plane of the coordinate system. It is assumed that x is opposite to the driving direction, the y axis is perpendicular to the x axis and points to the shoulder, and the z axis passes through the origin and is perpendicular to the xy plane, with the top of the road surface as the positive direction.

[0080] In this embodiment, according to Table 1 and Figure 3 , the relationship between the space vectors of the retroreflector axis, reference axis, observation axis and illumination axis in the Cartesian rectangular coordinate system is as follows:

[0081] R=(x 1 ,y 1 , z 1 ) T ;

[0082] D=(x 2 ,y 2 , z 2 ) T ;

[0083] E=(x 3 ,y 3 , z 3 ) T ;

[0084] I=(x 4 ,y 4 , z 4 ) T ;

[0085] Where T is the transpose, and xyz in the relationship are all measured values.

[0086] Based on the above relationship, the spatial vectors of the retroreflector axis, reference axis, observation axis and illumination body axis are calculated; the current observation angle is calculated based on the spatial vector of the observation axis, the spatial vector of the illumination body axis and the calculation formula of the observation angle; the current incident angle is calculated based on the spatial vector of the retroreflector axis and the spatial vector of the illumination body axis.

[0087] The calculation formula of observation angle α is:

[0088]

[0089] Among them, E is the space vector of the observation axis, I is the space vector of the illumination body axis, |E| is the absolute value of the space vector of the observation axis, and |I| is the absolute value of the space vector of the illumination body axis.

[0090] The calculation formula for the incident angle β is:

[0091]

[0092] Among them, R is the space vector of the retroreflector axis, I is the space vector of the illumination axis, |R| is the absolute value of the space vector of the retroreflector axis, and |I| is the absolute value of the space vector of the illumination axis.

[0093] Step S105, determining whether the current observation angle and the current incident angle are consistent with the preset observation angle and the preset incident angle.

[0094] Step S106: if the current observation angle and the current incident angle are inconsistent with the preset observation angle and the preset incident angle, a local coordinate system is established based on the position of the retroreflection coefficient detection device.

[0095] With respect to step S106, a local coordinate system of the current posture and a local coordinate system of the preset target posture are established based on the Cartesian rectangular coordinate system of the retroreflection coefficient detection device.

[0096] In this embodiment, the Cartesian rectangular coordinate system establishes the functional relationship between the actual observation angle and the incident angle and the actual measurement distance, but cannot solve the posture adjustment problem of the test equipment, that is, the rotation of the rigid body. Therefore, it is necessary to introduce the Euler angle to establish the local coordinate system of the retroreflection coefficient detection device. The Euler angle is used to uniquely determine the position of the fixed-point rotating rigid body. It consists of the nutation angle θ, the precession angle ψ and the rotation angle ω.

[0097] Figure 4 It is a structural block diagram of the local coordinate system provided in an embodiment of the present application.

[0098] like Figure 4As shown, assuming that the posture of the retroreflection coefficient detection device is adjusted to rigid body motion, a local coordinate system of the current posture is established on the basis of the rectangular coordinate system Oxyz with the origin as O, the observation angle is the angle of the preset observation angle, and the incident angle is the angle of the preset incident angle. The rigid body coordinate system Ox'y'z' is established, that is, the observation angle is the angle of the current observation angle, and the incident angle is the angle of the current incident angle. The local coordinate system of the preset target posture is established under the state of the angle of the current observation angle and the angle of the current incident angle. The axes Oz and Oz' are the basic axes, and their vertical planes Oxy and Ox'y' are the basic planes. The angle θ measured from the axis Oz to Oz' is called the nutation angle. The perpendicular line ON of the plane zOz' is called the node line, which is the intersection of the basic planes Ox'y' and Oxy. In the coordinate system of the right-hand screw rule, the nutation angle θ should be measured in the counterclockwise direction from the positive end of ON. The angle ψ measured from the fixed axis Ox to the node line ON is called the precession angle, and the angle ω measured from the node line ON to the moving axis Ox' is called the rotation angle. The nutation angle θ, the precession angle ψ and the rotation angle ω constitute the adjustment angle of the retroreflection coefficient detection equipment.

[0099] Step S107, obtaining the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculating the posture adjustment angle based on the transformation relationship.

[0100] For step S107, the Euler angles between the local coordinate system of the current posture and the local coordinate system of the preset target posture are obtained, and a rotation matrix is ​​established based on the Euler angles and the transformation relationship;

[0101] Get the posture adjustment sequence and build the Euler transformation matrix based on the rotation matrix;

[0102] Determine the posture adjustment formula based on the Euler transformation matrix;

[0103] Calculate the attitude adjustment angle based on the attitude adjustment matrix.

[0104] In this embodiment, the transformation relationship between the local coordinates and the Cartesian rectangular coordinate system is as follows:

[0105] x=x′cos(x,x′)+y′cos(x,y′)+z′cos(x,z′);

[0106] y=x′cos(y,x′)+y′cos(y,y′)+z′cos(y,z′);

[0107] z=x′cos(z,x′)+y′cos(z,y′)+z′cos(z,z′);

[0108] Among them, cos is the angle between two coordinates in the two local coordinate systems, and the vector sum of the three vectors in the local coordinate system is the vector of the Cartesian rectangular coordinate system.

[0109] Although the above three rotations are performed in a three-dimensional Cartesian coordinate system, they are all plane rotations. The rotation matrices established based on Euler angles and transformation relationships are:

[0110]

[0111]

[0112]

[0113] According to the order of posture adjustment, the Euler transformation matrix from the rectangular coordinate system to the local coordinate system is:

[0114] Based on the Euler transformation matrix, the calculation formula of the attitude angle can be deduced as follows:

[0115]

[0116] Substituting the above-mentioned actual measured data into the formula can calculate the posture adjustment angle of the retroreflection coefficient detection device.

[0117] Step S108, adjusting the posture of the retroreflection coefficient detection device based on the posture adjustment angle, and measuring the retroreflection coefficient of the target to be detected based on the adjusted posture.

[0118] In this embodiment, the establishment of the Euler transformation matrix and the calculation formula of the attitude angle are both related to the attitude adjustment order. The attitude adjustment order is the adjustment order of the nutation angle θ, the precession angle ψ and the rotation angle ω, that is, when performing the attitude adjustment, which angle is rotated first? The rotation order can be set according to actual needs. If no setting is made, the matrix and formula are established in the order of the nutation angle θ, the rotation angle ω and the precession angle ψ. The specific attitude adjustment order is not specifically limited here.

[0119] In this embodiment, under ideal conditions, when the posture is adjusted, the position of the projection light source does not need to be adjusted, but in actual applications, the posture of the receiver is first adjusted. After the posture adjustment of the receiver is completed, the vertical distance between the receiver and the projection light source is adjusted so that the observation angle reaches the required 0.2 degrees.

[0120] Figure 5 A structural block diagram of a road sign retroreflection coefficient detection device 200 provided in an embodiment of the application.

[0121] like Figure 5 As shown, the road sign retroreflection coefficient detection device 200 mainly includes:

[0122] A position acquisition module 201 is used to acquire the position of the retroreflection coefficient detection device and establish a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device;

[0123] The center confirmation module 202 is used to obtain image information of the target to be detected and determine the center point of the target to be detected based on the image information;

[0124] An axis determination module 203, for determining a retroreflector axis, a reference axis, an observation axis and an illumination axis based on a Cartesian rectangular coordinate system and a center point of the target to be detected;

[0125] An angle calculation module 204, used to calculate the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis;

[0126] An angle determination module 205, used to determine whether the angle of the current observation angle and the angle of the current incident angle are consistent with the angle of the preset observation angle and the angle of the preset incident angle;

[0127] A coordinate establishing module 206, for establishing a local coordinate system based on the position of the retroreflection coefficient detection device if the angle of the current observation angle and the angle of the current incident angle are inconsistent with the angle of the preset observation angle and the angle of the preset incident angle;

[0128] A posture calculation module 207, used to obtain the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculate the posture adjustment angle based on the transformation relationship;

[0129] The device adjustment module 208 is used to adjust the posture of the retroreflection coefficient detection device based on the posture adjustment angle, and measure the retroreflection coefficient of the target to be detected based on the adjusted posture.

[0130] As an optional implementation of this embodiment, the angle calculation module 204 is specifically used to obtain the distance between the retroreflection coefficient detection device and the target to be detected; determine the spatial vectors of the retroreflector axis, the reference axis, the observation axis and the illumination body axis in the Cartesian rectangular coordinate system based on the distance; calculate the angle of the current observation angle based on the spatial vector of the observation axis and the spatial vector of the illumination body axis; calculate the angle of the current incident angle based on the spatial vector of the retroreflector axis and the spatial vector of the illumination body axis.

[0131] As an optional implementation of this embodiment, the center confirmation module 202 is specifically used to obtain the image geometry of the target to be detected, and calculate the center point of the target to be detected based on the image geometry.

[0132] As an optional implementation of this embodiment, the coordinate establishment module 206 is specifically used to establish a local coordinate system of the current posture and a local coordinate system of the preset target posture based on the Cartesian rectangular coordinate system of the retroreflection coefficient detection device.

[0133] As an optional implementation of this embodiment, the posture calculation module 207 is specifically used to obtain the Euler angle between the local coordinate system of the current posture and the local coordinate system of the preset target posture, and establish a rotation matrix based on the Euler angle and the transformation relationship; obtain the posture adjustment order, and establish the Euler transformation matrix based on the rotation matrix; determine the posture adjustment formula based on the Euler transformation matrix; and calculate the posture adjustment angle based on the posture adjustment matrix.

[0134] As an optional implementation of this embodiment, the position acquisition module 201 is specifically used to obtain the real-time relative distance between the vehicle equipped with the retroreflection coefficient detection device and the target to be detected, and determine whether the real-time relative distance reaches the preset distance range; if the real-time relative distance reaches the preset distance range, obtain the safe parking position and park at the safe parking position; obtain the safe parking position, and determine the position of the retroreflection coefficient detection device based on the safe parking position; establish a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device.

[0135] In one example, the module in any of the above devices can be one or more integrated circuits configured to implement the above methods, such as: one or more application specific integrated circuits (ASICs), or, one or more digital signal processors (DSPs), or, one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms.

[0136] For another example, when the modules in the device can be implemented in the form of a processing element scheduling program, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call a program. For another example, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0137] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0138] Figure 6 This is a structural block diagram of an electronic device 300 provided in an embodiment of the present application.

[0139] like Figure 6As shown, the electronic device 300 includes a processor 301 and a memory 302 , and may further include an information input / information output (I / O) interface 303 , one or more of a communication component 304 , and a communication bus 305 .

[0140] The processor 301 is used to control the overall operation of the electronic device 300 to complete all or part of the steps of the road sign retroreflection coefficient detection method described above; the memory 302 is used to store various types of data to support the operation of the electronic device 300, and these data may include, for example, instructions for any application or method used to operate on the electronic device 300, and data related to the application. The memory 302 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0141] The I / O interface 303 provides an interface between the processor 301 and other interface modules, and the above-mentioned other interface modules can be keyboards, mice, buttons, etc. These buttons can be virtual buttons or physical buttons. The communication component 304 is used for wired or wireless communication between the electronic device 300 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G or 4G, or a combination of one or more of them, so the corresponding communication component 104 can include: Wi-Fi components, Bluetooth components, NFC components.

[0142] The electronic device 300 can be implemented by one or more application specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), field programmable gate arrays (FPGA), controllers, microcontrollers, microprocessors or other electronic components to execute the road sign retroreflection coefficient detection method given in the above embodiment.

[0143] The communication bus 305 may include a path to transmit information between the above components. The communication bus 305 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The communication bus 305 may be divided into an address bus, a data bus, a control bus, etc.

[0144] The electronic device 300 may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc., and may also be servers, etc.

[0145] Figure 7 This is a structural block diagram of a road sign retroreflection coefficient detection system provided in an embodiment of the present application.

[0146] like Figure 7 As shown, a road sign retroreflection coefficient detection system includes an electronic device 300, a vehicle-mounted retroreflection coefficient detection device 400, a distance sensor 500 and an image acquisition device 600;

[0147] The retroreflection coefficient detection device 400 is used to detect the retroreflection coefficient of the device to be detected and send the retroreflection coefficient to the electronic device;

[0148] The distance sensor 500 is used to detect the distance between the retroreflection coefficient detection device and the target to be detected, and send the distance to the electronic device;

[0149] The image acquisition device 600 is used to acquire image information of the target to be detected and send the image information to the electronic device.

[0150] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned road sign retroreflection coefficient detection method are implemented.

[0151] The computer-readable storage medium may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0152] The terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus.

[0153] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of application involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the aforementioned application concept. For example, the above features are replaced with (but not limited to) technical features with similar functions applied in the present application.

Claims

1. A method for detecting retroreflection coefficient of road signs, characterized in that: include: Acquire the position of the retroreflection coefficient detection device, and establish a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device; Acquire image information of a target to be detected, and determine a center point of the target to be detected based on the image information; Determine the retroreflector axis, the reference axis, the observation axis and the illumination axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected; Calculate the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis; Determining whether the angle of the current observation angle and the angle of the current incident angle are consistent with the angle of the preset observation angle and the angle of the preset incident angle; If the angle of the current observation angle and the angle of the current incident angle are inconsistent with the angle of the preset observation angle and the angle of the preset incident angle, establishing a local coordinate system based on the position of the retroreflection coefficient detection device; Acquire a transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculate a posture adjustment angle based on the transformation relationship; The posture of the retroreflection coefficient detection device is adjusted based on the posture adjustment angle, and the retroreflection coefficient of the target to be detected is measured based on the adjusted posture.

2. The method according to claim 1, characterized in that The calculation of the current observation angle and the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis comprises: Acquiring the distance between the retroreflection coefficient detection device and the target to be detected; Determine the space vectors of the retroreflector axis, the reference axis, the observation axis and the illumination axis in the Cartesian rectangular coordinate system based on the distance; Calculate the angle of the current observation angle based on the spatial vector of the observation axis and the spatial vector of the illumination body axis; The angle of the current incident angle is calculated based on the space vector of the retroreflector axis and the space vector of the illuminating body axis.

3. The method according to claim 1, characterized in that The acquiring image information of the target to be detected and determining the center point of the target to be detected based on the image information comprises: The image geometry of the target to be detected is acquired, and the center point of the target to be detected is calculated based on the image geometry.

4. The method according to claim 1, characterized in that: The establishing of a local coordinate system based on the position of the retroreflection coefficient detection device comprises: A local coordinate system of the current posture and a local coordinate system of the preset target posture are established on the basis of the Cartesian rectangular coordinate system of the retroreflection coefficient detection device.

5. The method according to claim 4, characterized in that The acquiring the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculating the posture adjustment angle based on the transformation relationship comprises: Acquire the Euler angles between the local coordinate system of the current posture and the local coordinate system of the preset target posture, and establish a rotation matrix based on the Euler angles and the transformation relationship; Acquire a posture adjustment sequence, and establish an Euler transformation matrix based on the rotation matrix of the posture adjustment sequence; Determine a posture adjustment formula based on the Euler transformation matrix; The posture adjustment angle is calculated based on the Euler transformation matrix.

6. The method according to claim 1, characterized in that The obtaining of the position of the retroreflection coefficient detection device and establishing a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device comprises: Obtaining the real-time relative distance between the vehicle equipped with the retroreflection coefficient detection device and the target to be detected, and determining whether the real-time relative distance reaches a preset distance range; If the real-time relative distance reaches a preset distance range, a safe parking position is acquired and the vehicle is controlled to park at the safe parking position; Acquire the safe parking position, and determine the position of the retroreflection coefficient detection device based on the safe parking position; A Cartesian rectangular coordinate system is established based on the position of the retroreflection coefficient detection device.

7. A road sign retroreflection coefficient detection device, characterized in that: include: A position acquisition module, used to acquire the position of the retroreflection coefficient detection device, and establish a Cartesian rectangular coordinate system based on the position of the retroreflection coefficient detection device; A center confirmation module is used to obtain image information of the target to be detected and determine the center point of the target to be detected based on the image information; An axis determination module, used for determining a retroreflector axis, a reference axis, an observation axis and an illumination axis based on the Cartesian rectangular coordinate system and the center point of the target to be detected; An angle calculation module, used for calculating the angle of the current observation angle and the angle of the current incident angle based on the retroreflector axis, the reference axis, the observation axis and the illumination axis; An angle determination module, used to determine whether the angle of the current observation angle and the angle of the current incident angle are consistent with the angle of the preset observation angle and the angle of the preset incident angle; A coordinate establishment module, for establishing a local coordinate system based on the position of the retroreflection coefficient detection device if the angle of the current observation angle and the angle of the current incident angle are inconsistent with the angle of the preset observation angle and the angle of the preset incident angle; A posture calculation module, used for obtaining the transformation relationship between the local coordinate system and the Cartesian rectangular coordinate system, and calculating the posture adjustment angle based on the transformation relationship; The device adjustment module is used to adjust the posture of the retroreflection coefficient detection device based on the posture adjustment angle, and measure the retroreflection coefficient of the target to be detected based on the adjusted posture.

8. An electronic device, characterized in that: comprising a processor coupled to a memory; The processor is configured to execute a computer program stored in the memory, so that the electronic device executes the method according to any one of claims 1 to 6.

9. A road sign retroreflection coefficient detection system, characterized in that: It comprises a vehicle-mounted retroreflection coefficient detection device, a distance sensor, an image acquisition device and the electronic device as claimed in claim 8; The vehicle-mounted retroreflection coefficient detection device is used to detect the retroreflection coefficient of the target to be detected and send the retroreflection coefficient to the electronic device; The distance sensor is used to detect the distance between the retroreflection coefficient detection device and the target to be detected, and send the distance to the electronic device; The image acquisition device is used to acquire image information of the target to be detected and send the image information to the electronic device.

10. A computer-readable storage medium, characterized in that: The method comprises a computer program or an instruction, which, when executed on a computer, causes the computer to execute the method according to any one of claims 1 to 6.

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