A Computable Road Network Generation Method for Microscopic Traffic Simulation

Abstract

The present invention discloses a method for generating a computable road network for microscopic traffic simulation. The user draws the centerline of each road section of the simulated real road network, sets a default lane width and the number of lanes for each road section, and specifies each pair of upstream connecting lanes and downstream connecting lanes. The basic road network is first automatically generated through steps S2 to S4. The user then adjusts the three types of adjustable parameters for each road section to automatically adjust the length, width, and offset distance of the lanes of the initially cut lane centerlines in the corresponding road section of the basic road network. A new smooth connecting curve is automatically generated between each pair of upstream third-adjustment lane centerlines and downstream third-adjustment lane centerlines to form a computable road network that is connected to form the simulated real road network. The present invention has the advantages of high editing freedom of the computable road network shape, high degree of restoration to the real road network, simple operation, and high degree of automation.

Description

Technical Field

[0001] The present invention relates to a simulation of a road vehicle traffic control system, and in particular to a computable road network generation method for microscopic traffic simulation. Background Art

[0002] Computable road network generation is a crucial foundational function in road traffic simulation. Before simulating real-world scenarios, most traffic simulation software requires a digital representation of the scenario's road network to generate a computable road network upon which to build various simulation models, such as car-following and lane-changing models.

[0003] The resulting computable road network should closely resemble the real-world network, be logically structured to facilitate the operation of various traffic simulation models, and be constructed with minimal complexity and automation. However, real-world road networks vary in shape, and the computable road network generation methods used by existing mainstream microscopic traffic simulation software fall short in terms of fidelity and editing complexity in certain scenarios, such as toll plazas, merges, and divergences. SUMO and TransModeler employ similar road network generation methods, both drawing segment centerlines and specifying node-lane connectivity between segments. However, SUMO's lane widths are not adjustable, and node shapes are difficult to modify. TransModeler's lane widths at both ends of a segment cannot be adjusted separately, and the node connection lines are rigid. Vissim's lane widths at both ends of a segment are also not adjustable, and segments are connected by constructing connectors, a cumbersome process. Connectors are logically isolated from each other, preventing vehicles from changing lanes across them. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a computable road network generation method for microscopic traffic simulation, so as to solve the problems of low degree of restoration of the appearance shape of the real road network and cumbersome operation in the existing computable road network generation method for microscopic traffic simulation software.

[0005] To solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0006] A computable road network generation method for microscopic traffic simulation, characterized by comprising:

[0007] Step S1, see Figure 2 The user draws the centerline EDGE of each road section SEC of the simulated real road network through the graphical front-end interface. The centerline EDGE is a directed straight line segment; wherein any two road sections SEC connected in front and behind in the simulated real road network are recorded as upstream sections SEC u and downstream section SEC d , the upstream section SECu The end point of the center line EDGE of the road section is the downstream section SEC d The starting point of the center line EDGE of the road section;

[0008] Step S2, see Figure 3 The user sets a default lane width w and the number of lanes of each road section SEC of the simulated real road network, so as to automatically generate, for each road section SEC: a number of lane center lines LANE equal to the set number of lanes;

[0009] The generation rule is as follows: the lane centerline LANE is a directed straight line segment with the same length and direction as the section centerline EDGE in the same section SEC (that is, the lane centerline LANE of the corresponding section SEC can be formed by translating the section centerline EDGE along its normal direction), and all lane centerlines LANE in the same section SEC are arranged at equal intervals along the normal direction of the section centerline EDGE of the section SEC with the default lane width w as the interval; and if the number of lanes in the section SEC is odd, the section centerline EDGE of the section SEC coincides with a lane centerline LANE in the center position, Figure 3 The example shows the case where the number of lanes in the two connected sections SEC is 3. If the number of lanes in the section SEC is even, the two lane centerlines LANE in the middle of the section SEC are symmetrically distributed about the section centerline EDGE.

[0010] Step S3, see Figure 3 and Figure 4 , automatically perform initial clipping on the lane centerline LANE generated in step S2, so that any upstream road segment SEC u and downstream section SEC d The initially cut lane center lines CROP_LANE do not overlap with each other; wherein, the initially cut lane center line CROP_LANE is a directed straight line segment obtained by initially cutting the lane center line LANE;

[0011] Step S4, see Figure 5 The user specifies each pair of upstream connected lanes and downstream connected lanes in the simulated real road network, so that the connection segment generation algorithm can automatically cut the center line of each pair of upstream lanes CROP_LANE u，l and the downstream preliminary lane centerline CROP_LANE d，m A smooth connecting curve is generated between them as the center line of the connecting lane CON_LANE, which is connected to form the corresponding basic road network; wherein, the upstream connecting lane and the downstream connecting lane are respectively the upstream road segment SEC u and downstream section SEC dThe upstream lane centerline of the connected lane is CROP_LANE u，l and the downstream preliminary lane centerline CROP_LANE d，m They are respectively the preliminary lane center lines CROP_LANE of the upstream connecting lane and the downstream connecting lane;

[0012] Among them, l represents the upstream preliminary lane centerline CROP_LANE u，l It is the upstream section SEC u The lth preliminary lane centerline CROP_LANE in the , m represents the downstream preliminary lane centerline CROP_LANE d，m It is the downstream section SEC d The mth preliminary lane centerline CROP_LANE in CROP_LANE; l and m are not specific or necessarily equal values, and are specified by the user based on the actual situation of the simulated real road network; and an upstream connecting lane may be connected to multiple downstream connecting lanes, for example Figure 11 At the lane divergence node P1 in , multiple upstream connecting lanes may also be connected to the same downstream connecting lane, for example Figure 11 Lane confluence node P2 in.

[0013] Step S5, see Figure 5 、 Figures 8 to 11 The user adjusts the three types of adjustable parameters of each of the road sections SEC, so as to automatically perform the lane length adjustment processing, lane width adjustment processing and lane offset distance adjustment processing on the preliminary lane center line CROP_LANE in the corresponding road section SEC in sequence based on the basic road network generated in step S4, so as to become the third adjusted lane center line ADJ3_LANE. In addition, the third adjusted lane center line ADJ3_LANE is automatically adjusted on each pair of upstream lanes through the connection segment generation algorithm. u，l and the downstream third adjustment lane centerline ADJ3_LANE d，m A new smooth connecting curve is generated between the two as the connecting lane centerline CON_LANE, which is connected to form the computable road network of the simulated real road network; wherein, the upstream third adjustment lane centerline ADJ3_LANE u，l and the downstream third adjustment lane centerline ADJ3_LANE d，m The third adjusted lane center lines ADJ3_LANE of the upstream connecting lane and the downstream connecting lane respectively;

[0014] The three types of adjustable parameters are: the lane trimming lengths at both ends, including the start end trimming length start_c and the end end trimming length end_c; the lane widths at both ends, including the start end lane width start_w and the end end lane width end_w; and the lane offset distances at both ends, including the start end offset distance and the end end offset distance end_d.

[0015] See also Figure 5 and Figure 8 , the lane length adjustment process at both ends is as follows: Figure 5 Each lane centerline CROP_LANE in the same road section SEC shown in FIG. 1 is cut from the starting point and the end point by the starting end cutting length start_c and the end end cutting length end_c set by the user for the road section SEC, to form Figure 8 The first adjustment lane centerline ADJ1_LANE is shown; Figure 8 In the example shown, the value of the starting end clipping length start_c is 0, and the value of the ending end clipping length end_c is not 0.

[0016] See also Figure 8 and Figure 9 , the lane width adjustment process at both ends is as follows:

[0017] For each first-adjustment lane centerline ADJ1_LANE in the same road section SEC, its starting point and end point are respectively translated along the normal direction of the section centerline EDGE of the road section SEC to become the second-adjustment lane centerline ADJ2_LANE;

[0018] The translation distances of the start and end points of the first adjusted lane centerline ADJ1_LANE are such that the distance between the start points and the distance between the end points of any two adjacent second adjusted lane centerlines ADJ2_LANE in the road section SEC are the start lane width start_w and the end lane width end_w set by the user for the road section SEC, respectively.

[0019] Furthermore, if the number of lanes in the road section SEC is an odd number, such as Figure 8 As shown, the position of the first adjustment lane centerline ADJ1_LANE in the middle of the road section SEC remains unchanged and directly becomes Figure 9 The second adjustment lane centerline ADJ2_LANE is shown;

[0020] If the number of lanes in the road section SEC is even, the two second adjustment lane center lines ADJ2_LANE located in the center of the road section SEC are symmetrically distributed about the road section center line EDGE of the road section SEC;

[0021] See also Figure 9 and Figure 10 , the lane offset distance adjustment process at both ends is as follows: Figure 9 Each second adjusted lane centerline ADJ2_LANE in the same road section SEC shown has its starting point translated along the normal direction of the road section centerline EDGE of the road section SEC by the starting end offset distance set by the user for the road section SEC, and its end point translated along the normal direction of the road section centerline EDGE of the road section SEC by the end end offset distance set by the user for the road section SEC, so as to become Figure 10 The third adjustment lane centerline ADJ3_LANE is shown; wherein, when the starting end offset distance or the ending end offset distance end_d is a positive number, it means that the starting point or the end point of the second adjustment lane centerline ADJ2_LANE is translated to the right side of the road section SEC; when the starting end offset distance or the ending end offset distance end_d is a negative number, it means that the starting point or the end point of the second adjustment lane centerline ADJ2_LANE is translated to the left side of the road section SEC.

[0022] Therefore, the principles and effects of the computable road network generation method of the present invention are as follows:

[0023] The present invention proposes three types of adjustable parameters in step S5, including: the end lane clipping length, the end lane width, and the end lane offset distance. Based on the user's adjustment of these three types of adjustable parameters for each road section SEC, the preliminary lane centerline CROP_LANE in the corresponding road section SEC of the basic road network is automatically adjusted in sequence for the end lane length, end lane width, and end lane offset distance. This can enhance the editing freedom of the computable road network shape to fully adapt to the various special line types existing in the highway road network as the simulated real road network, effectively improve the degree of restoration of the computable road network to the real road network in the micro-traffic simulation, and thus improve the accuracy of the simulation results of the micro-traffic simulation. The functions of the adjustment processing corresponding to the three types of adjustable parameters are as follows:

[0024] See also Figure 13 The lane length adjustment process at both ends is performed by changing the positions of the start and end points of each section SEC in the computable road network. This allows the computable road network to adapt to the situation where the distances between the section boundaries SEC_bou of different sections SEC under the same node P3 may be different from the node P3 in the highway network being simulated as a real road network.

[0025] See also Figure 14 and Figure 15, the lane width adjustment processing at both ends, by changing the distance between the starting point and the end point of the center line of two adjacent lanes in the same section SEC of the computable road network, the computable road network can be adapted to: in the highway network as the simulated real road network, there are Figure 15 The situation of the gradient road section and its related node shapes shown;

[0026] See also Figure 16 and Figure 17 , the lane offset distance adjustment process at both ends, by changing the distance between the starting point and the end point of each lane center line in the same section SEC of the computable road network relative to the section center line, can make the computable road network adapt to: as the highway network being simulated, there are Figure 17 The figure shows the situation where different road sections SEC under the same node P4 do not strictly intersect at one point geometrically.

[0027] Moreover, in the process of generating a computable road network according to the present invention, the user only needs to draw the center line EDGE of the road section, set the default lane width w and the number of lanes, and specify the lane connectivity relationship at the road section nodes to generate a basic road network. On this basis, by fine-tuning the three types of adjustable parameters, a computable road network can be automatically obtained whose appearance shape and internal logical structure are highly similar to the real road network. Therefore, it has the advantages of simple operation and high degree of automation.

[0028] In summary, the present invention has the advantages of high editing freedom in calculating the shape of the road network, high degree of restoration of the actual road network, simple operation and high degree of automation.

[0029] In addition, after testing: Figure 18 The simulated real road network shown in FIG. 1 is a diagram showing a user drawing a center line EDGE of each road section SEC of the simulated real road network through step S1 of the present invention. Figure 2 As shown, Figure 2 The computable road network obtained through the processing of steps S2 to S5 of the present invention is as follows: Figure 11 As shown in Figure 11 On each of the third adjustment lane center lines ADJ3_LANE and the connecting lane center lines CON_LANE of the computable road network shown, the corresponding lanes are rendered, that is, the lanes obtained by the present invention can be obtained. Figure 12 The computable road network effect diagram shown in Figure 2 is shown in Figure 2. Figures 19 to 21 The editors in SUMO software, TransModeler software and Vissim software are used to Figure 18 The calculated road network effect diagram obtained by simulating the real road network is shown in the figure. Figure 18 、 Figure 12 、 Figures 19 to 21By comparison, it can be clearly judged that: the Figure 12 right Figure 18 The degree of restoration of the simulated real road network is extremely high, and the degree of restoration is higher than Figures 19 to 21 The computable road network renderings shown are obtained using the SUMO software's built-in editor, the TransModeler software's built-in editor, and the Vissim software's built-in editor.

[0030] Preferably, in step S1, the graphical front-end interface displays a satellite map of the simulated real road network, and the user draws the road section centerline EDGE on the satellite map, so that the user can conveniently draw the road section centerline EDGE directly according to the straight lane on the satellite map;

[0031] In step S5, the computable road network is displayed as an overlay on the satellite map of the simulated real road network, so that the user can easily and accurately adjust the three types of adjustable parameters based on the differences between the computable road network and the satellite map until a computable road network with a sufficiently high degree of restoration of the simulated real road network is obtained.

[0032] As a preferred embodiment of the present invention: Figure 3 and Figure 4 As shown, in step S3, the method for automatically performing initial clipping on the lane centerline LANE generated in step S2 is:

[0033] Step S3-1: For any upstream segment SEC u and downstream section SEC d , get the key point set KEY_POINTS of the downstream section d and upstream road segment key point set KEY_POINTS u :

[0034] KEY_POINTS d =(POINTS cp ∪ POINTS d，s )∩ POINTS u ;

[0035] KEY_POINTS u =(POINTS cp ∪ POINTS u，e )∩ POINTS d ;

[0036] In the formula, the intersection point set POINTS cp Contains all intersections of the upstream end point peripheral line segment and the downstream start point peripheral line segment, the upstream end point peripheral line segment is formed by the upstream segment SEC uThe two lane center lines LANE at the outermost position and the line LINK connecting the end points of the two lane center lines LANE u，e The downstream starting point side peripheral line segment is composed of the downstream section SEC d The two lane center lines LANE at the outermost position and the line LINK connecting the starting points of the two lane center lines LANE d，s Composition; downstream outer starting point set POINTS d，s Contains the downstream section SEC d The starting point of the center line of the two lanes at the outermost position; the upstream coverage point set POINTS u Indicates the coverage area COV of the outer segment at the upstream end point u Points inside; upstream outer endpoint set POINTS u，e Including the upstream section SEC u The end points of the center lines of the two outermost lanes; the downstream coverage point set POINTS d Indicates the coverage area COV of the outer line segment on the downstream starting point side d points inside; ∪ represents the union, and ∩ represents the intersection.

[0037] For example: Figure 3 , the intersection set POINTS cp Contains intersection points cp1 and cp2; downstream outer starting point set POINTS d，s Contains the starting point start d1 and starting point start d2 ; Upstream outer endpoint set POINTS u，e Contains the end point u1 and end point u2 ; Among them, the starting point start d1 Coverage area COV of the outer segment that is not on the upstream end side u End u1 Coverage area COV of the outer line segment that is not on the downstream starting point side d Therefore, the downstream key point set KEY_POINTS d The key points of the downstream section include intersection cp1, intersection cp2 and starting point start d2 ;Key point set KEY_POINTS of upstream section u The key points of the upstream section include intersection cp1, intersection cp2 and end point end u2 .

[0038] Step S3-2: Calculate the downstream road segment key point set KEY_POINTS dEach point in the link to the end point LINK u，e The maximum of the vertical distances calculated is recorded as the minimum cutting length MIN on the upstream end side. u，e ;

[0039] And, calculate the upstream section key point set KEY_POINTS u Each point in the link to the starting point LINK d，s The maximum of the vertical distances calculated is recorded as the minimum cutting length MIN on the downstream starting point side. d，s ;

[0040] Step S3-3: Starting from the end point, the upstream section SEC u Each lane centerline LANE is cut, and the cutting length is the minimum cutting length MIN on the upstream end side u，e ;

[0041] And, starting from the starting point, the downstream section SEC d Each lane centerline LANE is trimmed, and the trimming length is the minimum trimming length MIN on the downstream starting side d，s .

[0042] Therefore, the present invention performs initial clipping on the lane centerline LANE generated in step S2 by the method from step S3-1 to step S3-2, so that any upstream section SEC u and downstream section SEC d The center lines of the initially cut lanes CROP_LANE do not overlap;

[0043] Furthermore, the present invention calculates the minimum cutting length MIN of the upstream end side. u，e SEC on the upstream section u The lane centerline LANE end end is cut and the calculated minimum cutting length MIN on the downstream starting side is used. d，s For downstream section SEC d The lane centerline LANE starting point is cut, and while ensuring that the initial lane centerlines CROP_LANE do not overlap with each other, the upstream section SEC can be more balanced. u The lane centerline LANE end and downstream section SEC d The starting end of the lane centerline LANE is clipped to avoid clipping one of them too little or too much, which causes the connection segment generation algorithm in step S4 and step S5 to be unable to generate a reasonable connection curve as the connection segment lane centerline CON_LANE.

[0044] As a preferred embodiment of the present invention: Figures 5 to 7and Figure 10 As shown, the upstream lane center line CROP_LANE in step S4 is u，l and the upstream third adjustment lane centerline ADJ3_LANE in step S5 u，l Both are recorded as the upstream lane centerline LANE u，l , and the downstream lane centerline CROP_LANE in step S4 is d，m and the downstream third adjustment lane centerline ADJ3_LANE in step S5 d，m All are recorded as the downstream lane centerline LANE d，m ;

[0045] The method of generating a smooth connecting curve as the center line CON_LANE of the connecting lane by the connecting segment generation algorithm includes:

[0046] Step 1: Generate the upstream lane centerline LANE u，l and the downstream lane centerline LANE d，m The initial connection point set CONN_POINTS0 between (0) , cp0 (1) , cp0 (2) , cp0 (3) , cp0 (4)};in:

[0047] See also Figure 6 , if the upstream lane centerline LANE u，l and the downstream lane centerline LANE d，m The intersection point CP of the extended line is located at the center line of the upstream lane LANE u，l After the end point and located on the downstream lane centerline LANE d，m Before the starting point, then: connect point cp0 (2) Set it as the intersection point CP of the extension line, and connect the point cp0 (0) Set to the upstream lane centerline LANE u，l The end point will be connected to point cp0 (4) Set to the downstream lane centerline LANE d，m The starting point, and connect point cp0 (1) Set to connection point cp0 (0) and the connection point cp0 (2) The midpoint of the connection point cp0 (3) Set to the connection point cp0 (2) and connection point cp0 (4) midpoint;

[0048] If the upstream lane centerline LANEu，l and the downstream lane centerline LANE d，m The intersection point CP of the extended line is located at the center line of the upstream lane LANE u，l Before the end of Figure 7 ) or located at the center line of the downstream lane LANE d，m After the starting point (not shown in the figure), then: connect point cp0 (0) Set to the upstream lane centerline LANE u，l The end point will be connected to point cp0 (4) Set to the downstream lane centerline LANE d，m The starting point and connect point cp0 (2) Set to connection point cp0 (0) and connection point cp0 (4) The midpoint of (1) Set to the connection point cp0 (2) To the center line of the upstream lane LANE u，l The vertical point of the extension line of the connecting point cp0 (3) Set to the connection point cp0 (2) To the center line of the downstream lane LANE d，m The perpendicular point of the extension line;

[0049] Step 2: Generate the upstream lane centerline LANE by iteration u，l and the downstream lane centerline LANE d，m The new connection point set between the two, the connection point set generated by the jth iteration is recorded as N is the maximum number of iterations of the preset step 2, where:

[0050] Connection point set CONN_POINTS j The number of connection points in P is 5+j; j-1 Represents the connection point set CONN_POINTS generated by the j-1th iteration j-1 The number of connection points in ;

[0051] Connect the point cp j (0) and connection points Set as connection point set CONN_POINTS in sequence j-1 The connection point cp in j-1 (0) and connection points And, connect the point cp j (P) Set as connection point cp j-1 (P-1) and connection point cp j-1(P) The midpoint of , 1≤P≤P j-1 -1; for example: connection point cp j (1) For the connection point cp j-1 (0) and connection point cp j-1 (1) The midpoint of the connection point cp j (2) For the connection point cp j-1 (1) and connection point cp j-1 (2) midpoint.

[0052] In the case of j=1, the connection point set CONN_POINTS j-1 That is, the initial connection point set CONN_POINTS0 generated in step 1, the number of connection points P0 in the initial connection point set CONN_POINTS0 = 5;

[0053] Step 3: The connection point set CONN_POINTS generated by the Nth iteration of step 2 j＝N The 5+N connection points in are connected to form a smooth connection curve as the center line of the connection lane CON_LANE, wherein the larger the value of the maximum number of iterations N is, the smoother and more continuous the smooth connection curve formed by the connection is.

[0054] Therefore, the present invention adopts the connection segment generation algorithm described in steps 1 to 3, without the user having to manually set additional curve control points, and can generate a smooth connection curve as the center line CON_LANE of the connection segment lane, which has the advantage of a high degree of automation.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] First, the present invention allows the user to draw the section center line EDGE of each road section SEC of the simulated real road network, and sets the default lane width w and the number of lanes of each road section SEC, as well as designates each pair of upstream connected lanes and downstream connected lanes in the simulated real road network, so as to automatically generate the basic road network through steps S2 to S4; then the user adjusts the three types of adjustable parameters of each road section SEC, so as to automatically perform the lane length adjustment processing, lane width adjustment processing and lane offset distance adjustment processing on the preliminary lane center line CROP_LANE in the corresponding road section SEC of the basic road network in sequence, so as to become the third adjusted lane center line ADJ3_LANE, and automatically adjust the third adjusted lane center line ADJ3_LANE on each pair of upstream third adjusted lane center lines ADJ3_LANE u，l and the downstream third adjustment lane centerline ADJ3_LANEd，m A new smooth connecting curve is generated as the center line CON_LANE of the connecting lane, which is connected to form a computable road network of the simulated real road network.

[0057] Furthermore, the present invention proposes three types of adjustable parameters in step S5, including: the clipping length of the lanes at both ends, the width of the lanes at both ends, and the offset distance of the lanes at both ends. Based on the user's adjustment of these three types of adjustable parameters for each road section SEC, the center line CROP_LANE of the initially cut lanes in the corresponding road section SEC of the basic road network is automatically adjusted in sequence for the length of the lanes at both ends, the width of the lanes at both ends, and the offset distance of the lanes at both ends. This can enhance the editing freedom of the computable road network shape to fully adapt to the various special line types existing in the highway road network as the simulated real road network, effectively improve the degree of restoration of the computable road network to the real road network in the micro-traffic simulation, and thus improve the accuracy of the simulation results of the micro-traffic simulation. The functions of the adjustment processing corresponding to the three types of adjustable parameters are as follows:

[0058] See also Figure 13 The lane length adjustment process at both ends is performed by changing the positions of the start and end points of each section SEC in the computable road network. This allows the computable road network to adapt to the situation where the distances between the section boundaries SEC_bou of different sections SEC under the same node P3 may be different from the node P3 in the highway network being simulated as a real road network.

[0059] See also Figure 14 and Figure 15 , the lane width adjustment processing at both ends, by changing the distance between the starting point and the end point of the center line of two adjacent lanes in the same section SEC of the computable road network, the computable road network can be adapted to: in the highway network as the simulated real road network, there are Figure 15 The situation of the gradient road section and its related node shapes shown;

[0060] See also Figure 16 and Figure 17 , the lane offset distance adjustment process at both ends, by changing the distance between the starting point and the end point of each lane center line in the same section SEC of the computable road network relative to the section center line, can make the computable road network adapt to: as the highway network being simulated, there are Figure 17 The figure shows the situation where different road sections SEC under the same node P4 do not strictly intersect at one point geometrically.

[0061] Moreover, in the process of generating a computable road network according to the present invention, the user only needs to draw the center line EDGE of the road section, set the default lane width w and the number of lanes, and specify the lane connectivity relationship at the road section nodes to generate a basic road network. On this basis, by fine-tuning the three types of adjustable parameters, a computable road network can be automatically obtained whose appearance shape and internal logical structure are highly similar to the real road network. Therefore, it has the advantages of simple operation and high degree of automation.

[0062] In summary, the present invention has the advantages of high editing freedom in calculating the shape of the road network, high degree of restoration of the actual road network, simple operation and high degree of automation.

[0063] Second, the present invention performs initial clipping on the lane centerline LANE generated in step S2 by the method from step S3-1 to step S3-2, so that any upstream section SEC u and downstream section SEC d The center lines of the initially cut lanes CROP_LANE do not overlap;

[0064] Furthermore, the present invention calculates the minimum cutting length MIN of the upstream end side. u，e SEC on the upstream section u The lane centerline LANE end end is cut and the calculated minimum cutting length MIN on the downstream starting side is used. d，s For downstream section SEC d The lane centerline LANE starting point is cut, and while ensuring that the initial lane centerlines CROP_LANE do not overlap with each other, the upstream section SEC can be more balanced. u The lane centerline LANE end and downstream section SEC d The starting end of the lane centerline LANE is clipped to avoid clipping one of them too little or too much, which causes the connection segment generation algorithm in step S4 and step S5 to be unable to generate a reasonable connection curve as the connection segment lane centerline CON_LANE.

[0065] Third, the present invention adopts the connection segment generation algorithm described in steps 1 to 3, without the user having to manually set additional curve control points, and can generate a smooth connection curve as the center line CON_LANE of the connection segment lane, which has the advantage of a high degree of automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0067] Figure 1 A flow chart of the computable road network generation method of the present invention;

[0068] Figure 2A schematic diagram of the center line of the road section obtained by drawing in step S1 of the present invention;

[0069] Figure 3 A schematic diagram of the lane centerline automatically generated in step S2 of the present invention;

[0070] Figure 4 This is a schematic diagram of the initial lane centerline obtained by automatically performing initial cutting in step S3 of the present invention;

[0071] Figure 5 This is a schematic diagram of automatically generating a connecting lane centerline between the upstream preliminary lane centerline and the downstream preliminary lane centerline in step S4 of the present invention;

[0072] Figure 6 A schematic diagram of one case of generating an initial connection point set by the connection segment generation algorithm of the present invention;

[0073] Figure 7 This is a schematic diagram of the second case of generating an initial connection point set by the connection segment generation algorithm of the present invention;

[0074] Figure 8 Step S5 of the present invention is Figure 5 Schematic diagram after adjusting the lane lengths at both ends;

[0075] Figure 9 Step S5 of the present invention is Figure 8 Schematic diagram after lane width adjustment at both ends;

[0076] Figure 10 Step S5 of the present invention is Figure 9 Schematic diagram after adjusting the lane offset distance at both ends;

[0077] Figure 11 for Figure 2 A schematic diagram of a computable road network obtained after processing steps S2 to S5 of the present invention;

[0078] Figure 12 for Figure 11 Computable road network rendering after lanes are rendered;

[0079] Figure 13 A schematic diagram of a highway network in which the distances between the boundary of different road sections under the same node and the node are different;

[0080] Figure 14 A schematic diagram of a highway network with non-gradient sections and the shapes of its nodes;

[0081] Figure 15 A schematic diagram of a highway network with gradient sections and the shapes of its nodes;

[0082] Figure 16 A schematic diagram showing the intersection of different sections at the same node in the highway network;

[0083] Figure 17 This is a schematic diagram of different sections of the highway network not strictly intersecting at one point at the same node;

[0084] Figure 18 To draw Figure 2 Satellite map of the real road network being simulated;

[0085] Figure 19 For SUMO software's built-in editor Figure 18 Draw the resulting computable road network rendering;

[0086] Figure 20 TransModeler software comes with an editor for Figure 18 Draw the resulting computable road network rendering;

[0087] Figure 21 For Vissim software's built-in editor Figure 18 Draw the resulting computable road network rendering. DETAILED DESCRIPTION

[0088] The present invention is described in detail below in conjunction with the embodiments and the accompanying drawings to help those skilled in the art better understand the inventive concept of the present invention. However, the scope of protection of the claims of the present invention is not limited to the following embodiments. For those skilled in the art, all other embodiments obtained without creative work without departing from the inventive concept of the present invention shall fall within the scope of protection of the present invention.

[0089] Example 1

[0090] like Figures 1 to 12 As shown, the present invention discloses a computable road network generation method for microscopic traffic simulation, comprising:

[0091] Step S1, see Figure 2 The user draws the centerline EDGE of each road section SEC of the simulated real road network through the graphical front-end interface. The centerline EDGE is a directed straight line segment; wherein any two road sections SEC connected in front and behind in the simulated real road network are recorded as upstream sections SEC u and downstream section SEC d , the upstream section SEC u The end point of the center line EDGE of the road section is the downstream section SEC d The starting point of the center line EDGE of the road section;

[0092] Step S2, see Figure 3 The user sets a default lane width w and the number of lanes of each road section SEC of the simulated real road network, so as to automatically generate, for each road section SEC: a number of lane center lines LANE equal to the set number of lanes;

[0093] The generation rule is as follows: the lane centerline LANE is a directed straight line segment with the same length and direction as the section centerline EDGE in the same section SEC (that is, the lane centerline LANE of the corresponding section SEC can be formed by translating the section centerline EDGE along its normal direction), and all lane centerlines LANE in the same section SEC are arranged at equal intervals along the normal direction of the section centerline EDGE of the section SEC with the default lane width w as the interval; and if the number of lanes in the section SEC is odd, the section centerline EDGE of the section SEC coincides with a lane centerline LANE in the center position, Figure 3 The example shows the case where the number of lanes in the two connected sections SEC is 3. If the number of lanes in the section SEC is even, the two lane centerlines LANE in the middle of the section SEC are symmetrically distributed about the section centerline EDGE.

[0094] Step S3, see Figure 3 and Figure 4 , automatically perform initial clipping on the lane centerline LANE generated in step S2, so that any upstream road segment SEC u and downstream section SEC d The initially cut lane center lines CROP_LANE do not overlap with each other; wherein, the initially cut lane center line CROP_LANE is a directed straight line segment obtained by initially cutting the lane center line LANE;

[0095] Step S4, see Figure 5 The user specifies each pair of upstream connected lanes and downstream connected lanes in the simulated real road network, so that the connection segment generation algorithm can automatically cut the center line of each pair of upstream lanes CROP_LANE u，l and the downstream preliminary lane centerline CROP_LANE d，m A smooth connecting curve is generated between them as the center line of the connecting lane CON_LANE, which is connected to form the corresponding basic road network; wherein, the upstream connecting lane and the downstream connecting lane are respectively the upstream road segment SEC u and downstream section SEC d The upstream lane centerline of the connected lane is CROP_LANE u，l and the downstream preliminary lane centerline CROP_LANE d，mThey are respectively the preliminary lane center lines CROP_LANE of the upstream connecting lane and the downstream connecting lane;

[0096] Among them, l represents the upstream preliminary lane centerline CROP_LANE u，l It is the upstream section SEC u The lth preliminary lane centerline CROP_LANE in the , m represents the downstream preliminary lane centerline CROP_LANE d，m It is the downstream section SEC d The mth preliminary lane centerline CROP_LANE in CROP_LANE; l and m are not specific or necessarily equal values, and are specified by the user based on the actual situation of the simulated real road network; and an upstream connecting lane may be connected to multiple downstream connecting lanes, for example Figure 11 At the lane divergence node P1 in , multiple upstream connecting lanes may also be connected to the same downstream connecting lane, for example Figure 11 Lane confluence node P2 in.

[0097] Step S5, see Figure 5 、 Figures 8 to 11 The user adjusts the three types of adjustable parameters of each of the road sections SEC, so as to automatically perform the lane length adjustment processing, lane width adjustment processing and lane offset distance adjustment processing on the preliminary lane center line CROP_LANE in the corresponding road section SEC in sequence based on the basic road network generated in step S4, so as to become the third adjusted lane center line ADJ3_LANE. In addition, the third adjusted lane center line ADJ3_LANE is automatically adjusted on each pair of upstream lanes through the connection segment generation algorithm. u，l and the downstream third adjustment lane centerline ADJ3_LANE d，m A new smooth connecting curve is generated between the two as the connecting lane centerline CON_LANE, which is connected to form the computable road network of the simulated real road network; wherein, the upstream third adjustment lane centerline ADJ3_LANE u，l and the downstream third adjustment lane centerline ADJ3_LANE d，m The third adjusted lane center lines ADJ3_LANE of the upstream connecting lane and the downstream connecting lane respectively;

[0098] The three types of adjustable parameters are: the lane trimming lengths at both ends, including the start end trimming length start_c and the end end trimming length end_c; the lane widths at both ends, including the start end lane width start_w and the end end lane width end_w; and the lane offset distances at both ends, including the start end offset distance and the end end offset distance end_d.

[0099] See also Figure 5 and Figure 8 , the lane length adjustment process at both ends is as follows: Figure 5 Each lane centerline CROP_LANE in the same road section SEC shown in FIG. 1 is cut from the starting point and the end point by the starting end cutting length start_c and the end end cutting length end_c set by the user for the road section SEC, to form Figure 8 The first adjustment lane centerline ADJ1_LANE is shown; Figure 8 In the example shown, the value of the starting end clipping length start_c is 0, and the value of the ending end clipping length end_c is not 0.

[0100] See also Figure 8 and Figure 9 , the lane width adjustment process at both ends is as follows:

[0101] For each first-adjustment lane centerline ADJ1_LANE in the same road section SEC, its starting point and end point are respectively translated along the normal direction of the section centerline EDGE of the road section SEC to become the second-adjustment lane centerline ADJ2_LANE;

[0102] The translation distances of the start and end points of the first adjusted lane centerline ADJ1_LANE are such that the distance between the start points and the distance between the end points of any two adjacent second adjusted lane centerlines ADJ2_LANE in the road section SEC are the start lane width start_w and the end lane width end_w set by the user for the road section SEC, respectively.

[0103] Furthermore, if the number of lanes in the road section SEC is an odd number, such as Figure 8 As shown, the position of the first adjustment lane centerline ADJ1_LANE in the middle of the road section SEC remains unchanged and directly becomes Figure 9 The second adjustment lane centerline ADJ2_LANE is shown;

[0104] If the number of lanes in the road section SEC is even, the two second adjustment lane center lines ADJ2_LANE located in the center of the road section SEC are symmetrically distributed about the road section center line EDGE of the road section SEC;

[0105] See also Figure 9 and Figure 10 , the lane offset distance adjustment process at both ends is as follows: Figure 9Each second adjusted lane centerline ADJ2_LANE in the same road section SEC shown has its starting point translated along the normal direction of the road section centerline EDGE of the road section SEC by the starting end offset distance set by the user for the road section SEC, and its end point translated along the normal direction of the road section centerline EDGE of the road section SEC by the end end offset distance set by the user for the road section SEC, so as to become Figure 10 The third adjustment lane centerline ADJ3_LANE is shown; wherein, when the starting end offset distance or the ending end offset distance end_d is a positive number, it means that the starting point or the end point of the second adjustment lane centerline ADJ2_LANE is translated to the right side of the road section SEC; when the starting end offset distance or the ending end offset distance end_d is a negative number, it means that the starting point or the end point of the second adjustment lane centerline ADJ2_LANE is translated to the left side of the road section SEC.

[0106] Therefore, the principles and effects of the computable road network generation method of the present invention are as follows:

[0107] The present invention proposes three types of adjustable parameters in step S5, including: the end lane clipping length, the end lane width, and the end lane offset distance. Based on the user's adjustment of these three types of adjustable parameters for each road section SEC, the preliminary lane centerline CROP_LANE in the corresponding road section SEC of the basic road network is automatically adjusted in sequence for the end lane length, end lane width, and end lane offset distance. This can enhance the editing freedom of the computable road network shape to fully adapt to the various special line types existing in the highway road network as the simulated real road network, effectively improve the degree of restoration of the computable road network to the real road network in the micro-traffic simulation, and thus improve the accuracy of the simulation results of the micro-traffic simulation. The functions of the adjustment processing corresponding to the three types of adjustable parameters are as follows:

[0108] See also Figure 13 The lane length adjustment process at both ends is performed by changing the positions of the start and end points of each section SEC in the computable road network. This allows the computable road network to adapt to the situation where the distances between the section boundaries SEC_bou of different sections SEC under the same node P3 may be different from the node P3 in the highway network being simulated as a real road network.

[0109] See also Figure 14 and Figure 15 , the lane width adjustment processing at both ends, by changing the distance between the starting point and the end point of the center line of two adjacent lanes in the same section SEC of the computable road network, the computable road network can be adapted to: in the highway network as the simulated real road network, there are Figure 15 The situation of the gradient road section and its related node shapes shown;

[0110] See also Figure 16 and Figure 17 , the lane offset distance adjustment process at both ends, by changing the distance between the starting point and the end point of each lane center line in the same section SEC of the computable road network relative to the section center line, can make the computable road network adapt to: as the highway network being simulated, there are Figure 17 The figure shows the situation where different road sections SEC under the same node P4 do not strictly intersect at one point geometrically.

[0111] Moreover, in the process of generating a computable road network according to the present invention, the user only needs to draw the center line EDGE of the road section, set the default lane width w and the number of lanes, and specify the lane connectivity relationship at the road section nodes to generate a basic road network. On this basis, by fine-tuning the three types of adjustable parameters, a computable road network can be automatically obtained whose appearance shape and internal logical structure are highly similar to the real road network. Therefore, it has the advantages of simple operation and high degree of automation.

[0112] In summary, the present invention has the advantages of high editing freedom in calculating the shape of the road network, high degree of restoration of the actual road network, simple operation and high degree of automation.

[0113] In addition, after testing: Figure 18 The simulated real road network shown in FIG. 1 is a diagram showing a user drawing a center line EDGE of each road section SEC of the simulated real road network through step S1 of the present invention. Figure 2 As shown, Figure 2 The computable road network obtained through the processing of steps S2 to S5 of the present invention is as follows: Figure 11 As shown in Figure 11 On each of the third adjustment lane center lines ADJ3_LANE and the connecting lane center lines CON_LANE of the computable road network shown, the corresponding lanes are rendered, that is, the lanes obtained by the present invention can be obtained. Figure 12 The computable road network effect diagram shown in Figure 2 is shown in Figure 2. Figures 19 to 21 The editors in SUMO software, TransModeler software and Vissim software are used to Figure 18 The calculated road network effect diagram obtained by simulating the real road network is shown in the figure. Figure 18 、 Figure 12 、 Figures 19 to 21 By comparison, it can be clearly judged that: the Figure 12 right Figure 18 The degree of restoration of the simulated real road network is extremely high, and the degree of restoration is higher than Figures 19 to 21 The computable road network renderings shown are obtained using the SUMO software's built-in editor, the TransModeler software's built-in editor, and the Vissim software's built-in editor.

[0114] The above is a basic implementation of the first embodiment of the present invention. Further optimization, improvement and limitation can be made based on this basic implementation:

[0115] Preferably, in step S1, the graphical front-end interface displays a satellite map of the simulated real road network, and the user draws the road section centerline EDGE on the satellite map, so that the user can conveniently draw the road section centerline EDGE directly according to the straight lane on the satellite map;

[0116] In step S5, the computable road network is displayed as an overlay on the satellite map of the simulated real road network, so that the user can easily and accurately adjust the three types of adjustable parameters based on the differences between the computable road network and the satellite map until a computable road network with a sufficiently high degree of restoration of the simulated real road network is obtained.

[0117] Example 2

[0118] On the basis of the above-mentioned embodiment 1, this embodiment 2 further adopts the following preferred implementation manner:

[0119] like Figure 3 and Figure 4 As shown, in step S3, the method for automatically performing initial clipping on the lane centerline LANE generated in step S2 is:

[0120] Step S3-1: For any upstream segment SEC u and downstream section SEC d , get the key point set KEY_POINTS of the downstream section d and upstream road segment key point set KEY_POINTS u :

[0121] KEY_POINTS d =(POINTS cp ∪ POINTS d，s )∩ POINTS u ;

[0122] KEY_POINTS u =(POINTS cp ∪ POINTS u，e )∩ POINTS d ;

[0123] In the formula, the intersection point set POINTS cp Contains all intersections of the upstream end point peripheral line segment and the downstream start point peripheral line segment, the upstream end point peripheral line segment is formed by the upstream segment SEC uThe two lane center lines LANE at the outermost position and the line LINK connecting the end points of the two lane center lines LANE u，e The downstream starting point side peripheral line segment is composed of the downstream section SEC d The two lane center lines LANE at the outermost position and the line LINK connecting the starting points of the two lane center lines LANE d，s Composition; downstream outer starting point set POINTS d，s Contains the downstream section SEC d The starting point of the center line of the two lanes at the outermost position; the upstream coverage point set POINTS u Indicates the coverage area COV of the outer segment at the upstream end point u Points inside; upstream outer endpoint set POINTS u，e Including the upstream section SEC u The end points of the center lines of the two outermost lanes; the downstream coverage point set POINTS d Indicates the coverage area COV of the outer line segment on the downstream starting point side d points inside; ∪ represents the union, and ∩ represents the intersection.

[0124] For example: Figure 3 , the intersection set POINTS cp Contains intersection points cp1 and cp2; downstream outer starting point set POINTS d，s Contains the starting point start d1 and starting point start d2 ; Upstream outer endpoint set POINTS u，e Contains the end point u1 and end point u2 ; Among them, the starting point start d1 Coverage area COV of the outer segment that is not on the upstream end side u End u1 Coverage area COV of the outer line segment that is not on the downstream starting point side d Therefore, the downstream key point set KEY_POINTS d The key points of the downstream section include intersection cp1, intersection cp2 and starting point start d2 ;Key point set KEY_POINTS of upstream section u The key points of the upstream section include intersection cp1, intersection cp2 and end point end u2 .

[0125] Step S3-2: Calculate the downstream road segment key point set KEY_POINTS dEach point in the link to the end point LINK u，e The maximum of the vertical distances calculated is recorded as the minimum cutting length MIN on the upstream end side. u，e ;

[0126] And, calculate the upstream section key point set KEY_POINTS u Each point in the link to the starting point LINK d，s The maximum of the vertical distances calculated is recorded as the minimum cutting length MIN on the downstream starting point side. d，s ;

[0127] Step S3-3: Starting from the end point, the upstream section SEC u Each lane centerline LANE is cut, and the cutting length is the minimum cutting length MIN on the upstream end side u，e ;

[0128] And, starting from the starting point, the downstream section SEC d Each lane centerline LANE is trimmed, and the trimming length is the minimum trimming length MIN on the downstream starting side d，s .

[0129] Therefore, the present invention performs initial clipping on the lane centerline LANE generated in step S2 by the method from step S3-1 to step S3-2, so that any upstream section SEC u and downstream section SEC d The center lines of the initially cut lanes CROP_LANE do not overlap;

[0130] Furthermore, the present invention calculates the minimum cutting length MIN of the upstream end side. u，e SEC on the upstream section u The lane centerline LANE end end is cut and the calculated minimum cutting length MIN on the downstream starting side is used. d，s For downstream section SEC d The lane centerline LANE starting point is cut, and while ensuring that the initial lane centerlines CROP_LANE do not overlap with each other, the upstream section SEC can be more balanced. u The lane centerline LANE end and downstream section SEC d The starting end of the lane centerline LANE is clipped to avoid clipping one of them too little or too much, which causes the connection segment generation algorithm in step S4 and step S5 to be unable to generate a reasonable connection curve as the connection segment lane centerline CON_LANE.

[0131] Example 3

[0132] Based on the above-mentioned embodiment 1 or embodiment 2, this embodiment 3 further adopts the following preferred implementation manner:

[0133] like Figures 5 to 7 and Figure 10 As shown, the upstream lane center line CROP_LANE in step S4 is u，l and the upstream third adjustment lane centerline ADJ3-LANE in step S5 u，l Both are recorded as the upstream lane centerline LANE u，l , and the downstream lane centerline CROP_LANE in step S4 is d，m and the downstream third adjustment lane centerline ADJ3-LANE in step S5 d，m All are recorded as the downstream lane centerline LANE d，m ;

[0134] The method of generating a smooth connecting curve as the center line CON_LANE of the connecting lane by the connecting segment generation algorithm includes:

[0135] Step 1: Generate the upstream lane centerline LANE u，l and the downstream lane centerline LANE d，m The initial connection point set CONN_POINTS0 between (0) , cp0 (1) , cp0 (2) , cp0 (3) , cp0 (4)};in:

[0136] See also Figure 6 , if the upstream lane centerline LANE u，l and the downstream lane centerline LANE d，m The intersection point CP of the extended line is located at the center line of the upstream lane LANE u，l After the end point and located on the downstream lane centerline LANE d，m Before the starting point, then: connect point cp0 (2) Set it as the intersection point CP of the extension line, and connect the point cp0 (0) Set to the upstream lane centerline LANE u，l The end point will be connected to point cp0 (4) Set to the downstream lane centerline LANE d，m The starting point, and connect point cp0 (1) Set to connection point cp0 (0) and the connection point cp0 (2) The midpoint of the connection point cp0 (3) Set to the connection point cp0(2) and connection point cp0 (4) midpoint;

[0137] If the upstream lane centerline LANE u，l and the downstream lane centerline LANE d，m The intersection point CP of the extended line is located at the center line of the upstream lane LANE u，l Before the end of Figure 7 ) or located at the center line of the downstream lane LANE d，m After the starting point (not shown in the figure), then: connect point cp0 (0) Set to the upstream lane centerline LANE u，l The end point will be connected to point cp0 (4) Set to the downstream lane centerline LANE d，m The starting point and connect point cp0 (2) Set to connection point cp0 (0) and connection point cp0 (4) The midpoint of (1) Set to the connection point cp0 (2) To the center line of the upstream lane LANE u，l The vertical point of the extension line of the connecting point cp0 (3) Set to the connection point cp0 (2) To the center line of the downstream lane LANE d，m The perpendicular point of the extension line;

[0138] Step 2: Generate the upstream lane centerline LANE by iteration u，l and the downstream lane centerline LANE d，m The new connection point set between the two, the connection point set generated by the jth iteration is recorded as N is the maximum number of iterations of the preset step 2, where:

[0139] Connection point set CONN_POINTS j The number of connection points in P is 5+j; j-1 Represents the connection point set CONN_POINTS generated by the j-1th iteration j-1 The number of connection points in ;

[0140] Connect the point cp j (0) and connection points Set as connection point set CONN_POINTS in sequence j -1 in the connection point cp j-1 (0) and connection points And, connect the point cpj (P) Set as connection point cp j-1 (P-1) and connection point cp j-1 (P) The midpoint of , 1≤P≤P j-1 -1; for example: connection point cp j (1) For the connection point cp j-1 (0) and connection point cp j-1 (1) The midpoint of the connection point cp j (2) For the connection point cp j-1 (1) and connection point cp j-1 (2) midpoint.

[0141] In the case of j=1, the connection point set CONN_POINTS j -1 is the initial connection point set CONN_POINTS0 generated in step 1, and the number of connection points P0 in the initial connection point set CONN_POINTS0 is 5;

[0142] Step 3: The connection point set CONN_POINTS generated by the Nth iteration of step 2 j＝N The 5+N connection points in are connected to form a smooth connection curve as the center line of the connection lane CON_LANE, wherein the larger the value of the maximum number of iterations N is, the smoother and more continuous the smooth connection curve formed by the connection is.

[0143] Therefore, the present invention adopts the connection segment generation algorithm described in steps 1 to 3, without the user having to manually set additional curve control points, and can generate a smooth connection curve as the center line CON_LANE of the connection segment lane, which has the advantage of a high degree of automation.

[0144] The present invention is not limited to the above-mentioned specific implementation methods. According to the above content, in accordance with the common technical knowledge and customary means in this field, without departing from the above-mentioned basic technical ideas of the present invention, the present invention can also make other various forms of equivalent modifications, replacements or changes, all of which fall within the scope of protection of the present invention.

Claims

1. A computable road network generation method for microscopic traffic simulation, characterized in that: include: Step S1: The user draws the center line (EDGE) of each road section (SEC) of the simulated real road network through the graphical front-end interface. The center line (EDGE) of the road section is a directed straight line segment; wherein any two road sections (SEC) connected in the simulated real road network are recorded as upstream sections (SEC). u ) and downstream section (SEC d ), the upstream section (SEC u ) is the end point of the center line (EDGE) of the downstream section (SEC d ) is the starting point of the road section centre line (EDGE); Step S2: The user sets a default lane width (w) and the number of lanes for each road section (SEC) of the simulated real road network, and automatically generates, for each road section (SEC), a number of lane centerlines (LANE) equal to the set number of lanes; The generation rule is as follows: the lane centerline (LANE) is a directed straight line segment with the same length and direction as the segment centerline (EDGE) in the same road segment (SEC), and all lane centerlines (LANE) in the same road segment (SEC) are arranged at equal intervals along the normal direction of the segment centerline (EDGE) of the road segment (SEC) with the default lane width (w) as the interval; and if the number of lanes in the road segment (SEC) is odd, the segment centerline (EDGE) of the road segment (SEC) coincides with the lane centerline (LANE) in the center; if the number of lanes in the road segment (SEC) is even, the two lane centerlines (LANE) in the center of the road segment (SEC) are symmetrically distributed about the segment centerline (EDGE); Step S3, automatically perform initial clipping on the lane centerline (LANE) generated in step S2 so that any upstream road segment (SEC u ) and downstream section (SEC d ) do not overlap with each other; wherein, the preliminary cut lane center line (CROP_LANE) is a directed straight line segment obtained by initial clipping of the lane center line (LANE); Step S4: The user specifies each pair of upstream connected lanes and downstream connected lanes in the simulated real road network, and automatically cuts the center line of each pair of upstream lanes (CROP_LANE) through the connection segment generation algorithm. u,l ) and the downstream lane centerline (CROP_LANE d,m ) between the upstream connecting lane and the downstream connecting lane respectively as the center line of the connecting lane (CON_LANE), and the connection constitutes the corresponding basic road network; wherein, the upstream connecting lane and the downstream connecting lane are respectively the upstream road segment (SEC u ) and downstream section (SEC d ) in the connected lanes, the upstream preliminary lane centerline (CROP_LANE u,l ) and the downstream lane centerline (CROP_LANE d,m ) are the preliminary lane center lines (CROP_LANE) of the upstream connecting lane and the downstream connecting lane respectively; Step S5: The user adjusts the three types of adjustable parameters of each of the road sections (SEC) so as to automatically perform lane length adjustment, lane width adjustment and lane offset adjustment on the preliminary lane centerline (CROP_LANE) of the corresponding road section (SEC) based on the basic road network generated in step S4, to form the third adjusted lane centerline (ADJ3_LANE). Furthermore, the third adjusted lane centerline (ADJ3_LANE) is automatically added to each pair of upstream lanes through the connection segment generation algorithm. u,l ) and the downstream third adjustment lane centerline (ADJ3_LANE d,m ) between the upstream lane centerline (ADJ3_LANE) and the upstream lane centerline (ADJ3_LANE) are connected to form the computable road network of the simulated real road network; u,l ) and the downstream third adjustment lane centerline (ADJ3_LANE d,m ) are the third adjustment lane center lines (ADJ3_LANE) of the upstream connecting lane and the downstream connecting lane respectively; The three adjustable parameters are: the lane clipping lengths at both ends, including the start end clipping length (start_c) and the end end clipping length (end_c); the lane widths at both ends, including the start end lane width (start_w) and the end end lane width (end_w); and the lane offset distances at both ends, including the start end offset distance and the end end offset distance (end_d); The lane length adjustment process at both ends is as follows: for each initially cut lane centerline (CROP_LANE) in the same road section (SEC), it is cut from the starting point and the end point by the starting end cut length (start_c) and the end end cut length (end_c) set by the user for the road section (SEC) to form the first adjusted lane centerline (ADJ1_LANE); The lane width adjustment process at both ends is as follows: For each first-adjustment lane centerline (ADJ1_LANE) in the same road segment (SEC), its starting point and end point are translated along the normal direction of the road segment centerline (EDGE) of the road segment (SEC) to become the second-adjustment lane centerline (ADJ2_LANE); The translation distances of the start and end points of the first adjusted lane centerline (ADJ1_LANE) are such that the distance between the start points and the distance between the end points of any two adjacent second adjusted lane centerlines (ADJ2_LANE) in the road section (SEC) are the starting lane width (start_w) and the ending lane width (end_w) set by the user for the road section (SEC), respectively. Furthermore, if the number of lanes in the road section (SEC) is odd, the position of the first adjustment lane centerline (ADJ1_LANE) in the center of the road section (SEC) remains unchanged and directly becomes the second adjustment lane centerline (ADJ2_LANE); If the number of lanes of the road section (SEC) is even, the two second adjustment lane center lines (ADJ2_LANE) at the center of the road section (SEC) are symmetrically distributed about the section center line (EDGE) of the road section (SEC); The lane offset adjustment process at both ends is as follows: for each second-adjustment lane centerline (ADJ2_LANE) in the same road segment (SEC), its starting point is translated along the normal direction of the road segment centerline (EDGE) of the road segment (SEC) by the starting end offset distance set by the user for the road segment (SEC), and its end point is translated along the normal direction of the road segment centerline (EDGE) of the road segment (SEC) by the ending end offset distance (end_d) set by the user for the road segment (SEC), so as to become the third-adjustment lane centerline (ADJ3_LANE); wherein, when the starting end offset distance or the ending end offset distance (end_d) is a positive number, it indicates that the starting point or the ending point of the second-adjustment lane centerline (ADJ2_LANE) is translated to the right side of the road segment (SEC); when the starting end offset distance or the ending end offset distance (end_d) is a negative number, it indicates that the starting point or the ending point of the second-adjustment lane centerline (ADJ2_LANE) is translated to the left side of the road segment (SEC).

2. The method for generating a computable road network for microscopic traffic simulation according to claim 1, characterized in that: In step S1, the graphical front-end interface displays a satellite map of the simulated real road network, and the user draws the center line (EDGE) of the road section on the satellite map; In step S5, the computable road network is displayed overlaid on the satellite map of the simulated real road network.

3. The method for generating a computable road network for microscopic traffic simulation according to claim 1 or 2, characterized in that: In step S3, the method for automatically performing initial clipping on the lane centerline (LANE) generated in step S2 is: Step S3-1: For any upstream segment (SEC u ) and downstream section (SEC d ), get the key point set KEY_POINTS of the downstream section d and upstream road segment key point set KEY_POINTS u : KEY_POINTS d =(POINTS cp ∪POINTS d,s )∩POINTS u ; KEY_POINTS u =(POINTS cp ∪POINTS u,e )∩POINTS d ; In the formula, the intersection point set POINTS cp Contains all intersection points of the peripheral line segment on the upstream end side and the peripheral line segment on the downstream starting side, the peripheral line segment on the upstream end side is formed by the upstream segment (SEC u ) The two lane center lines (LANE) at the outermost position and the line connecting the end points of the two lane center lines (LANE) (LINK u,e ), the downstream starting point side peripheral line segment is composed of the downstream section (SEC d ) The two lane center lines (LANE) at the outermost position and the line connecting the starting points of the two lane center lines (LANE) (LINK d,s ) constitutes; downstream outer starting point set POINTS d,s Contains the downstream section (SEC d ) The starting point of the two lane center lines (LANE) at the outermost position; the upstream coverage point set POINTS u Indicates the coverage area of the peripheral line segment at the upstream end side (COV u ) points; upstream outer end point set POINTS u,e Contains the upstream section (SEC u ) the end points of the two outermost lane centre lines (LANE); Downstream coverage point set POINTS d Indicates the coverage area of the peripheral line segment on the downstream starting point side (COV d ); Step S3-2: Calculate the downstream road segment key point set KEY_POINTS d Each point in the link to the end point (LINK u,e ) vertical distance, the maximum of the calculated vertical distances is recorded as the minimum cutting length (MIN) on the upstream end side. u,e ); And, calculate the upstream section key point set KEY_POINTS u Each point in the link to the starting point (LINK d,s ) vertical distance, the maximum of the calculated vertical distances is recorded as the minimum cutting length (MIN) on the downstream starting point side. d,s ); Step S3-3, starting from the end point, the upstream section (SEC u ) is cut along each lane centerline (LANE), and the cut length is the minimum cut length (MIN u,e ); And, starting from the starting point, the downstream section (SEC d ) is cut along each lane centerline (LANE), and the cut length is the minimum cut length (MIN d,s ).

4. The method for generating a computable road network for microscopic traffic simulation according to claim 1 or 2, characterized in that: The upstream lane centerline (CROP_LANE u,l ) and the upstream third adjustment lane centerline (ADJ3_LANE u,l ) are recorded as the upstream lane centerline (LANE u,l ), and the downstream lane center line (CROP_LANE d,m ) and the downstream third adjustment lane centerline (ADJ3_LANE d,m ) are recorded as the downstream lane centerline (LANE d,m ); The method of the connecting segment generation algorithm generating a smooth connecting curve as the connecting segment lane centerline (CON_LANE) includes: Step 1: Generate the upstream lane centerline (LANE u,l ) and the downstream lane centerline (LANE d,m ) between the initial connection point set CONN_POINTS0 = {cp0 (0) ,cp0 (1) ,cp0 (2) ,cp0 (3) ,cp0 (4) };in: If the upstream lane centerline (LANE u,l ) and the downstream lane centerline (LANE d,m ) is located at the center line of the upstream lane (LANE u,l ) and located behind the end point of the downstream lane centerline (LANE d,m ) before the starting point, then: connect point cp0 (2) Set it as the intersection point (CP) of the extension line and connect point cp0 (0) Set as the upstream lane centerline (LANE u,l ) and connect point cp0 (4) Set to the downstream lane centerline (LANE d,m ) and connect point cp0 (1) Set to connection point cp0 (0) and the connection point cp0 (2) The midpoint of the connection point cp0 (3) Set to the connection point cp0 (2) and connection point cp0 (4) midpoint; If the upstream lane centerline (LANE u,l ) and the downstream lane centerline (LANE d,m ) is located at the center line of the upstream lane (LANE u,l ) or before the end of the downstream lane centerline (LANE d,m ) after the starting point, then: connect point cp0 (0) Set as the upstream lane centerline (LANE u,l ) and connect point cp0 (4) Set to the downstream lane centerline (LANE d,m ) and connect point cp0 (2) Set to connection point cp0 (0) and connection point cp0 (4) The midpoint of (1) Set to the connection point cp0 (2) To the center line of the upstream lane (LANE u,l ) and connect the point cp0 (3) Set to the connection point cp0 (2) To the center line of the downstream lane (LANE d,m ) is a point perpendicular to the extension line of the Step 2: Generate the upstream lane centerline (LANE) by iteration u,l ) and the downstream lane centerline (LANE d,m ), the set of connection points generated by the jth iteration is recorded as 1≤j≤N, N is the maximum number of iterations of the preset step 2, where: Connection point set CONN_POINTS j The number of connection points in P is 5+j; j-1 Represents the connection point set CONN_POINTS generated by the j-1th iteration j-1 The number of connection points in ; Connect the point cp j (0) and connection points Set as connection point set CONN_POINTS in sequence j-1 The connection point cp in j-1 (0) and connection points And, connect the point cp j (P) Set as connection point cp j-1 (P-1) and connection point cp j-1 (P) The midpoint of , 1≤P≤P j-1 -1; In the case of j=1, the connection point set CONN_POINTS j-1 The initial connection point set CONN_POINTS0 generated in step 1, the number of connection points P0 in the initial connection point set CONN_POINTS0 = 5; Step 3: The connection point set CONN_POINTS generated by the Nth iteration of step 2 j＝N The 5+N connection points in are connected to form a smooth connection curve as the center line of the connection segment lane (CON_LANE).

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