A highway virtual-real line alignment construction control method and system
By acquiring GPS and meter data to fit the boundary point normal equation and controlling the nozzle operation, the problem of low efficiency in the construction of dashed and solid lines on highways was solved, and automatic alignment and accurate line marking were achieved.
Patent Information
- Application Number
- CN202310443885.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-04-19
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2043-04-19
AI Technical Summary
In existing technologies, the construction of dashed and solid lines on highways involves a large workload and low efficiency, making it difficult to achieve automatic alignment.
By acquiring GPS sampling time data from the marking vehicle and sampling time data from the meter counter, the boundary point normal equation is fitted, and the nozzle operation is controlled to align the remaining dashed and solid lines with the first dashed and solid line.
It enables automatic alignment of solid and dashed lines during construction, improving construction efficiency, reducing the workload of construction workers, and ensuring the accuracy of line marking.
Smart Images
Figure CN116578085B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of highway traffic technology, and particularly relates to a highway virtual and real line alignment construction control method and system. BACKGROUND
[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.
[0003] In the past, when virtual and real lines of a highway are constructed, workers usually operate a hand-push line marking vehicle to perform line marking along a pre-marked water line. When marking the first virtual and real line, the head and tail positions of each virtual and real line segment need to be marked. When marking the second virtual and real line, the workers mark the second virtual and real line according to the pre-marked head and tail positions of each virtual and real line segment. This water line alignment method has a large workload and low efficiency. SUMMARY
[0004] To solve the above problems, the present application provides a highway virtual and real line alignment construction control method and system. When marking the first virtual and real line, the boundary points of each virtual and real line are determined, and then the normal equations of all boundary points are determined. When marking the remaining virtual and real lines, the position relationship between the position coordinates of the line marking vehicle and the normal equations of the boundary points is determined, and the running state of the spray head of the line marking vehicle is controlled, so that the remaining virtual and real lines are aligned with the first virtual and real line.
[0005] To achieve the above object, the present application adopts the following technical solutions:
[0006] In a first aspect, a highway virtual and real line alignment construction control method is provided, comprising:
[0007] GPS sampling time data, meter counter sampling time data and spray head running state during marking of the first virtual and real line by the line marking vehicle are acquired;
[0008] The acquired GPS sampling time data is fitted to obtain a fitting equation;
[0009] The boundary points of each virtual and real line are determined according to the spray head running state;
[0010] The last GPS sampling time data before the line marking vehicle reaches each virtual and real line boundary point is interpolated according to the meter counter data to obtain the coordinates of each virtual and real line boundary point;
[0011] The normal equation of the first virtual and real line fitting equation at each virtual and real line boundary point is calculated to obtain the normal equations of all boundary points;
[0012] When marking the remaining virtual and real lines, the GPS sampling time data and meter counter sampling time data of the line marking vehicle are acquired;
[0013] Interpolate the GPS sampling time data of each marking vehicle by the metering device sampling time data to obtain the position coordinates corresponding to each metering device sampling time;
[0014] Calculate the boundary point normal equation value when the obtained GPS sampling time data and each position coordinate are substituted into one of the boundary point normal equations, and change the running state of the spray head of the marking vehicle when the sign of the boundary point normal equation value changes or is zero.
[0015] In a second aspect, a highway virtual-real line alignment construction control system is provided, comprising:
[0016] The boundary point normal equation determination module is configured to obtain GPS sampling time data, metering device sampling time data, and spray head running states during the marking vehicle drawing the first virtual-real line; fit the obtained GPS sampling time data to obtain a fitting equation; determine each virtual-real line boundary point according to the spray head running state; interpolate the last GPS sampling time data before the marking vehicle reaches each virtual-real line boundary point according to the metering device data to obtain the coordinates of each virtual-real line boundary point; calculate the normal equation of the fitting equation at each virtual-real line boundary point to obtain all boundary point normal equations.
[0017] The remaining virtual-real line boundary point determination module is configured to obtain GPS sampling time data and metering device sampling time data of the marking vehicle when drawing the remaining virtual-real lines; interpolate the GPS sampling time data of each marking vehicle by the metering device sampling time data to obtain the position coordinates corresponding to each metering device sampling time; calculate the boundary point normal equation value when the obtained GPS sampling time data and each position coordinate are substituted into one of the boundary point normal equations, and change the running state of the spray head of the marking vehicle when the sign of the boundary point normal equation value changes or is zero.
[0018] In a third aspect, an electronic device is provided, comprising a memory and a processor, and computer instructions stored in the memory and running on the processor, when the computer instructions are run by the processor, the steps of a highway virtual-real line alignment construction control method are completed.
[0019] In a fourth aspect, a computer readable storage medium is provided for storing computer instructions, when the computer instructions are executed by a processor, the steps of a highway virtual-real line alignment construction control method are completed.
[0020] Compared with the prior art, the beneficial effects of the present application are:
[0021] 1、The present application determines the boundary points of each broken line when drawing the first broken line, and then determines the normal equation of all boundary points, and when drawing the remaining broken lines, determines whether the line marking vehicle reaches or passes the boundary point according to the positional relationship between the position coordinates of the line marking vehicle and the normal equation of each boundary point, thereby changing the running state of the spray head, so that the remaining broken lines are aligned with the first broken line, automatic alignment construction of the broken lines is realized, the road marking construction efficiency is greatly improved, the workload of the construction personnel is reduced, and the marking accuracy is ensured.
[0022] 2、In the present application, the GPS data is interpolated using the meter counter data when determining the boundary points of each broken line, so that the coordinates of the determined boundary points of the broken lines are more accurate, and the accuracy of the automatic alignment of the broken lines is further ensured.
[0023] 3、The present application determines the estimated direction of the vehicle by weighted summation of the difference between the gradient and the data of two GPS sampling times, improves the accuracy of the estimated direction of the vehicle, further ensures the accuracy of the coordinates of the boundary points of the broken lines, and realizes the automatic alignment of the broken lines.
[0024] The advantages of the additional aspects of the present application will be partially given in the following description, partially will become apparent from the following description, or will be understood by the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS
[0025] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application and explanations thereof serve to explain the application, and do not constitute an improper limitation of the application.
[0026] Fig. 1 A schematic diagram of the principle of the method disclosed in Example 1;
[0027] Fig. 2 A schematic diagram of the principle of the forward direction prediction of the line marking vehicle disclosed in Example 1;
[0028] Fig. 3 A schematic diagram of the principle of the determination of the boundary points of the remaining broken lines disclosed in Example 1. DETAILED DESCRIPTION
[0029] The present application will be further described below in conjunction with the drawings and examples.
[0030] It should be pointed out that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as understood by those skilled in the art.
[0031] Example 1
[0032] In this example, a highway broken line alignment construction control method is disclosed, as shown inFigs. 1-3 As shown, comprising:
[0033] S1: obtaining GPS sampling time data, metering device sampling time data and spray head running state in the process of drawing the first dash-dot line by the marking vehicle.
[0034] The length of the solid line and the interval length of adjacent dash-dot line segments are input at the control end of the marking vehicle, and the marking vehicle automatically draws the first dash-dot line according to the length of the solid line and the interval length of adjacent dash-dot line segments.
[0035] In the process of drawing the first dash-dot line by the marking vehicle, each GPS sampling time data, metering device sampling time data and spray head running state are obtained.
[0036] Through S n represents the running state of the spray head, when S n is equal to 1, the spray head is in the open state, and when S n is equal to 0, the spray head is in the closed state.
[0037] S2: fitting the obtained GPS data to obtain a fitting equation.
[0038] The forgetting factor recursive least squares is used to fit the obtained GPS data to obtain a fitting equation, which is specifically:
[0039] A third-order polynomial is used to construct the fitting equation, and the constructed fitting equation is:
[0040] x(k)=a3(k)k 3 +a2(k)k 2 +a1(k)k+a0(k);
[0041] y(k)=b3(k)k 3 +b2(k)k 2 +b1(k)k+b0(k)。
[0042] Wherein: a3, a2, a1, a0, b3, b2, b1, b0 represent unknown parameters to be estimated, y represents GPS vertical coordinate data, x represents GPS horizontal coordinate data, and k represents GPS sampling time.
[0043] The unknown parameters of the above polynomial are updated by using the recursive least squares method with forgetting factor, and the update formula is as follows:
[0044]
[0045]
[0046]
[0047] Wherein, The transpose matrix formed by the unknown parameters to be estimated, i.e. [a3(k) a2(k) a1(k) a0(k)] T Or [b3(k) b2(k) b1(k) b0(k)] T λ is a forgetting factor, usually selected in the range of 0.9-1.0, P(k) is a covariance matrix, I is a unit matrix, P(0)=10 6 I, y(k) is the GPS longitudinal coordinate at the sampling time k, x(k) is the GPS transverse coordinate at the sampling time k, The observation data vector, i.e. [x 3 (k) x 2 (k) x 1 (k)1] T Or [y 3 (k) y 2 (k) y 1 (k) 1] T .
[0048] S3: Determine the virtual-solid line boundary points according to the running state of the spray head; interpolate the last GPS sampling time data of the line marking vehicle before reaching each virtual-solid line boundary point according to the meter data to obtain the coordinates of each virtual-solid line boundary point; calculate the normal equation of the fitting equation at each virtual-solid line boundary point to obtain all the normal equations of the boundary points.
[0049] In this embodiment, the point at which the running state of the spray head changes is determined as the virtual-solid line boundary point.
[0050] Specifically, the difference between the adjacent two running state data is used to determine whether the virtual-solid line boundary point is the starting point or the ending point of the virtual-solid line.
[0051] label=S n -S n-1
[0052] Wherein, label is the difference between the adjacent two running state data, S n is the running state of the spray head at time n, S n-1 is the running state of the spray head at time n-1, when label>0, it indicates that the time n reaches the starting point position of the virtual-solid line, when label<0, it indicates that the time n reaches the ending point position of the virtual-solid line.
[0053] After determining the virtual-solid line boundary points, the last GPS sampling time data of the line marking vehicle before reaching each virtual-solid line boundary point is interpolated according to the meter data to obtain the coordinates of each virtual-solid line boundary point.
[0054] The process of determining the coordinates of the virtual-solid line boundary points includes:
[0055] S31: According to the fitting equation and the last two GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point, the advancing direction of the line marking vehicle is predicted to obtain the vehicle estimated direction, specifically:
[0056] According to the fitting equation, the gradient of the last GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point is calculated
[0057]
[0058] Wherein, x, y are the horizontal and vertical coordinates of the last GPS data of the line marking vehicle before reaching the virtual-real line boundary point, and k is the GPS sampling time.
[0059] The difference value of the last two GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point is calculated
[0060]
[0061] Wherein, y k , x k are the vertical and horizontal coordinates of the last GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point; y k-1 , x k-1 are the vertical and horizontal coordinates of the second last GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point.
[0062] The gradient of the last GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point is weighted and summed with the difference value of the last two GPS sampling time data of the line marking vehicle before reaching the virtual-real line boundary point to obtain the vehicle estimated direction
[0063]
[0064] Wherein, w is the weight.
[0065] S32: According to the odometer data of the line marking vehicle when reaching the virtual-real line boundary point and the odometer data of the line marking vehicle when obtaining the last GPS sampling time data before reaching the virtual-real line boundary point, the odometer difference data ΔS is determined.
[0066] ΔS=S n -S k .
[0067] Wherein, S n is the odometer data of the line marking vehicle when reaching the virtual-real line boundary point, and S k is the odometer data of the line marking vehicle when obtaining the last GPS sampling time data before reaching the virtual-real line boundary point.
[0068] S33: According to the vehicle estimated direction and the odometer difference data ΔS, the last GPS sampling time data G(k) of the line marking vehicle before reaching the virtual-solid line boundary point is interpolated to obtain the virtual-solid line boundary point coordinate G(n).
[0069]
[0070] The normal equation of the fitting equation at each virtual-solid line boundary point is calculated to obtain all the boundary point normal equations, and the boundary point normal equation is:
[0071] c(k)(y-y(n))+(x-x(n))=0.
[0072] wherein c(k) is the tangent slope of the fitting equation at the boundary point (x(n), y(n)).
[0073] According to the time sequence of the obtained boundary points, the obtained boundary point normal equations are numbered, the boundary point normal equation of the first boundary point is set as the first boundary point normal equation, the boundary point normal equation of the second boundary point is set as the second boundary point normal equation, and the numbering is sequentially performed for each boundary point normal equation.
[0074] S4: When drawing the remaining virtual-solid lines, the GPS sampling time data and the odometer sampling time data of the line marking vehicle are obtained; the GPS sampling time data of each line marking vehicle is interpolated by the odometer sampling time data to obtain the position coordinates corresponding to each odometer sampling time; the boundary point normal equation value when the obtained GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations is calculated, and when the sign of the boundary point normal equation value changes or is zero, the running state of the line marking vehicle nozzle is changed.
[0075] When the remaining virtual-solid lines are aligned and constructed with the first virtual-solid line, the GPS sampling time data and the odometer sampling time data of the line marking vehicle are obtained, and each GPS sampling time data is interpolated by the odometer sampling time data to obtain the position coordinates corresponding to each odometer sampling time.
[0076] The process of determining the position coordinates corresponding to each odometer sampling time is:
[0077] According to the fitting equation, the gradient of each GPS sampling time data is calculated;
[0078] The difference between the GPS sampling time data and the previous GPS sampling time data of the GPS data is calculated;
[0079] The gradient and the difference are weighted and summed to obtain the vehicle estimated direction when the line marking vehicle obtains the GPS data;
[0080] determining meter difference data according to the odometer data when the GPS sampling time data is acquired and the odometer data between the GPS sampling time and the next GPS sampling time;
[0081] interpolating the GPS sampling time data according to the meter difference data and the vehicle estimated direction when the GPS sampling time data is acquired by the marking vehicle to obtain the position coordinates corresponding to each meter sampling time between the GPS sampling time and the next GPS sampling time.
[0082] After the GPS sampling time data and the position coordinates are acquired, the GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations to calculate the boundary point normal equation value. When the sign of the boundary point normal equation value changes or is zero, it indicates that the boundary point is crossed or reached. At this time, the running state of the marking vehicle spray head is changed. The GPS sampling time data and the position coordinates acquired after the boundary point is crossed or reached are substituted into the next boundary point normal equation to calculate the boundary point normal equation value. When the sign of the boundary point normal equation value changes or is zero, the running state of the marking vehicle spray head is changed. The running state of the spray head is changed from the closed state to the open state, or the running state of the spray head is changed from the open state to the closed state, thereby realizing the alignment of the remaining dashed and solid lines with the first dashed and solid line.
[0083] In specific implementation, starting from the first boundary point normal equation, each GPS sampling time data and position coordinates are substituted into the first boundary point normal equation to calculate the corresponding boundary point normal equation value.
[0084] f(x(n1),y(n1))=c(k)(y(n1)-y(n))+(x(n1)-x(n))。
[0085] wherein f(x(n1),y(n1)) is the boundary point normal equation value calculated by substituting the GPS sampling time data or position coordinates (y(n1), x(n1)) into the first boundary point normal equation.
[0086] When f(x(n1),y(n1)) changes in sign compared with the previous boundary point normal equation value, or when f(x(n1),y(n1)) is equal to 0, it is determined that x(n1), y(n1) is a boundary point or crosses the boundary point. The running state of the spray head is changed. The GPS sampling time data and position coordinates acquired after x(n1), y(n1) are substituted into the second boundary point normal equation to calculate the boundary point normal equation value. When the sign of the boundary point normal equation value changes or is zero, the running state of the spray head is changed. In this way, the GPS sampling time data and position coordinates are substituted into all boundary point normal equations.
[0087] The embodiment further judges whether the marking vehicle reaches the set position according to the distance d between the GPS sampling time data and the normal equation of the first boundary point, and when the distance is less than a set value, it is indicated that the marking vehicle reaches the set position, and the construction control method disclosed in the embodiment is started.
[0088]
[0089] Since the speed of the marking vehicle is about 60 meters per minute, the vehicle travels about 20 cm in each GPS sampling period, and when the distance d is less than 30 cm, it is indicated that the spray head approaches the first boundary point, and it is indicated that the marking vehicle reaches the set position.
[0090] The method disclosed in the embodiment determines the boundary points of each broken line when drawing the first broken line, and further determines the normal equation of all boundary points, and when drawing the remaining broken lines, according to the positional relationship between the position coordinates of the marking vehicle and the normal equation of each boundary point, it is determined whether the marking vehicle reaches or crosses the boundary point, so as to change the running state of the spray head, so that the remaining broken lines are aligned with the first broken line, automatic alignment construction of the broken line is realized, the road marking construction efficiency is greatly improved, the workload of the construction personnel is reduced, and the marking precision is ensured.
[0091] Embodiment 2
[0092] In this embodiment, a highway broken line alignment construction control system is disclosed, comprising:
[0093] The boundary point normal equation determination module is configured to obtain GPS sampling time data, meter counter sampling time data and a spray head running state during the process of drawing the first broken line by the marking vehicle; fit the obtained GPS sampling time data to obtain a fitting equation; determine each broken line boundary point according to the spray head running state; interpolate the last GPS sampling time data before the marking vehicle reaches each broken line boundary point according to the meter counter data to obtain the coordinates of each broken line boundary point; calculate the normal equation of the fitting equation at each broken line boundary point to obtain all boundary point normal equations;
[0094] The boundary point determination module of the remaining broken line is configured to obtain GPS sampling time data and meter counter sampling time data of the marking vehicle when drawing the remaining broken lines; interpolate the GPS sampling time data of each marking vehicle through the meter counter sampling time data to obtain the position coordinates corresponding to each meter counter sampling time; calculate the boundary point normal equation value when the obtained GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations, and when the sign of the boundary point normal equation value changes or is zero, change the running state of the spray head of the marking vehicle.
[0095] Embodiment 3
[0096] In this embodiment, an electronic device is disclosed, comprising a memory and a processor, and computer instructions stored on the memory and running on the processor, when the computer instructions are run by the processor, the steps of the highway virtual and real line alignment construction control method disclosed in embodiment 1 are completed.
[0097] Embodiment 4
[0098] In this embodiment, a computer readable storage medium is disclosed, for storing computer instructions, when the computer instructions are executed by the processor, the steps of the highway virtual and real line alignment construction control method disclosed in embodiment 1 are completed.
[0099] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application rather than limit them, although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that: the specific embodiments of the present application can still be modified or replaced by the equivalent, without departing from the spirit and scope of the present application, any modification or equivalent replacement, which should be covered within the protection scope of the claims of the present application.
Claims
1. A highway virtual-real line alignment construction control method, characterized in that, The method comprises the following steps: acquiring GPS sampling time data, metering device sampling time data and nozzle running state during the first virtual and real line drawing process of the marking vehicle; fitting the acquired GPS sampling time data to obtain a fitting equation; determining each virtual and real line boundary point according to the nozzle running state; interpolating the last GPS sampling time data before the marking vehicle reaches each virtual and real line boundary point according to the metering device data to obtain the coordinates of each virtual and real line boundary point; calculating the normal equation of the fitting equation of the first virtual and real line at each virtual and real line boundary point to obtain all the boundary point normal equations; acquiring GPS sampling time data and metering device sampling time data of the marking vehicle during the drawing of the remaining virtual and real lines; interpolating the GPS sampling time data of each marking vehicle according to the metering device sampling time data to obtain the position coordinates corresponding to each metering device sampling time; calculating the boundary point normal equation value when the acquired GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations, and changing the running state of the nozzle of the marking vehicle when the sign of the boundary point normal equation value changes or is zero.
2. The method for highway virtual-real line alignment construction control according to claim 1, characterized in that, The marking vehicle draws the first virtual and real line according to the length of the real line and the interval length of the adjacent virtual line segments.
3. The method of highway construction control of the dashed line alignment according to claim 1, wherein, The point at which the running state of the nozzle changes is the virtual and real line boundary point.
4. The method of highway construction control of the dashed line alignment according to claim 1, wherein, The acquired GPS data is fitted by using the recursive least square method with a forgetting factor to obtain a fitting equation.
5. The method of highway construction control of the dashed line alignment according to claim 1, wherein, The advancing direction of the marking vehicle is predicted according to the fitting equation and the last two GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point to obtain a vehicle estimated direction; The metering device difference data is determined according to the metering device data when the marking vehicle reaches the virtual and real line boundary point and the metering device data when the last GPS sampling time data is acquired before the marking vehicle reaches the virtual and real line boundary point; The last GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point is interpolated according to the vehicle estimated direction and the metering device difference data to obtain the coordinates of the virtual and real line boundary point.
6. A method of highway construction control for aligning a virtual line with a real line as claimed in claim 5, wherein, The gradient of the last GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point is calculated according to the fitting equation; The difference between the last two GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point is calculated; The vehicle estimated direction is obtained by weighted sum of the gradient of the last GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point and the difference between the last two GPS sampling time data before the marking vehicle reaches the virtual and real line boundary point.
7. A method for highway construction control of virtual real line alignment as claimed in claim 1 wherein, The GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations to calculate the boundary point normal equation value, and when the sign of the boundary point normal equation value changes or is zero, it is determined that the boundary point is crossed or reached. The GPS sampling time data and the position coordinates obtained after the boundary point is crossed or reached are substituted into the next boundary point normal equation to calculate the boundary point normal equation value.
8. A highway virtual to real line alignment construction control system, characterized by, The method comprises the following steps: The boundary point normal equation determination module is configured to acquire GPS sampling time data, metering device sampling time data and spray head running state during the process of drawing the first dash-dot line by the marking vehicle, fit the acquired GPS sampling time data to obtain a fitting equation, determine each dash-dot line boundary point according to the spray head running state, interpolate the last GPS sampling time data before the marking vehicle reaches each dash-dot line boundary point according to the metering device data to obtain the coordinate of each dash-dot line boundary point, and calculate the normal equation of the fitting equation at each dash-dot line boundary point to obtain all boundary point normal equations. The remaining dash-dot line boundary point determination module is configured to acquire GPS sampling time data and metering device sampling time data of the marking vehicle during the process of drawing the remaining dash-dot lines, interpolate the GPS sampling time data of each marking vehicle according to the metering device sampling time data to obtain the position coordinates corresponding to each metering device sampling time, calculate the boundary point normal equation value when the acquired GPS sampling time data and the position coordinates are substituted into one of the boundary point normal equations, and change the running state of the spray head of the marking vehicle when the sign of the boundary point normal equation value changes or is zero.
9. An electronic device, comprising: The computer program product comprises a memory and a processor, and computer instructions stored in the memory and run on the processor, and when the computer instructions are run by the processor, the steps of the highway dash-dot line alignment construction control method in any one of claims 1-7 are completed.
10. A computer-readable storage medium, characterized in that, The computer program product is configured to store computer instructions, and when the computer instructions are executed by the processor, the steps of the highway dash-dot line alignment construction control method in any one of claims 1-7 are completed.
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