CN112762954B - A path planning method and system - Google Patents
- ️Tue Nov 02 2021
CN112762954B - A path planning method and system - Google Patents
A path planning method and system Download PDFInfo
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- CN112762954B CN112762954B CN202011561630.8A CN202011561630A CN112762954B CN 112762954 B CN112762954 B CN 112762954B CN 202011561630 A CN202011561630 A CN 202011561630A CN 112762954 B CN112762954 B CN 112762954B Authority
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/26—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network
- G01C21/34—Route searching; Route guidance
- G01C21/3453—Special cost functions, i.e. other than distance or default speed limit of road segments
- G01C21/3461—Preferred or disfavoured areas, e.g. dangerous zones, toll or emission zones, intersections, manoeuvre types, segments such as motorways, toll roads, ferries
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/26—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network
- G01C21/34—Route searching; Route guidance
- G01C21/3446—Details of route searching algorithms, e.g. Dijkstra, A*, arc-flags, using precalculated routes
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Abstract
本发明提供一种路径规划方法及系统,方法包括:首先确定n个典型路段;然后令h=1;基于模糊推理方法计算第h个未采样路段与各个典型路段的相似度;根据第h个未采样路段与各典型路段的相似度计算第h个未采样路段对应的速度权重;根据第h个未采样路段对应的速度权重计算第h个未采样路段对应的道路阻抗;直到h=K,其中K为未采样路段的总个数;最后根据各未采样路段对应的道路阻抗规划行驶路径。本发明基于道路阻抗越大,安全性越低的原理有效避免陡坡、视野狭窄的路段,减少安全性差的道路通过机会,从而为驾驶员山区道路安全出行规划行驶路径。
The invention provides a path planning method and system. The method includes: firstly determining n typical road sections; then setting h=1; calculating the similarity between the hth unsampled road section and each typical road section based on a fuzzy inference method; The similarity between the unsampled road section and each typical road section calculates the speed weight corresponding to the hth unsampled road section; calculates the road impedance corresponding to the hth unsampled road section according to the speed weight corresponding to the hth unsampled road section; until h=K, Among them, K is the total number of unsampled road sections; finally, the driving path is planned according to the road impedance corresponding to each unsampled road section. Based on the principle that the larger the road impedance is, the lower the safety is, the invention effectively avoids the road section with steep slope and narrow field of vision, reduces the chance of passing the road with poor safety, thereby planning the driving path for the driver to travel safely on the mountain road.
Description
Technical Field
The present invention relates to the field of path planning technologies, and in particular, to a path planning method and system.
Background
In recent years, with the increasing of automobile holding capacity, road traffic accidents caused by motor vehicles in road traffic are increasing, and the road traffic safety situation is becoming more severe. The mountainous area road has complex environment, short protection, rare people and narrow road, and is a main place for traffic accidents. At present, how to plan a safe driving path in a complex environment in a mountainous area becomes a hot point of research in the traffic field.
Disclosure of Invention
The invention aims to provide a path planning method and a system to plan a safe driving path.
In order to achieve the above object, the present invention provides a path planning method, including:
s1: determining n typical road sections;
s2: let h equal to 1;
s3: calculating the similarity between the h-th non-sampled road section and each typical road section based on a fuzzy reasoning method;
s4: calculating the speed weight corresponding to the h-th non-sampled road section according to the similarity of the h-th non-sampled road section and each typical road section;
s5: calculating the road impedance corresponding to the h-th non-sampled road section according to the speed weight corresponding to the h-th non-sampled road section;
s6: judging whether h is smaller than K; if h is less than K, let h be h +1, and return to "S3"; if h is greater than or equal to K, "S7" is performed; k is the total number of the non-sampled road sections;
s7: and planning a driving path according to the road impedance corresponding to each non-sampled road section.
Optionally, the determining n typical road segments specifically includes:
s11: collecting a plurality of sample road sections; the sample road segment comprises m road attribute values and speed weights;
s12: classifying a plurality of sample road sections by using a random forest method and training a prediction model;
s13: calculating first speed weight of each non-sampling road section according to the prediction model;
s14: determining n representative road segments according to the first speed weight of each non-sampled road segment and the speed weights of a plurality of sample road segments.
Optionally, the similarity between the h-th non-sampled road segment and each typical road segment is calculated based on a fuzzy inference method, and a specific formula is as follows:
wherein, Pj,hJ-th road attribute value, S, representing h-th unsampled road segmenti,hRepresenting the similarity, k, of the h-th unsampled road segment to the i-th typical road segment1And w1Denotes a correction parameter, Pjt,hAnd j represents the j-th road attribute value of each typical road section corresponding to the h-th unexplored road section, and m is the number of the road attribute values.
Optionally, the speed weight corresponding to the h-th non-sampled road section is calculated according to the similarity between the h-th non-sampled road section and each typical road section, and the specific formula is as follows:
wherein, WhRepresents the speed weight corresponding to the h-th non-sampled road section, Si,hRepresents the similarity of the h-th non-sampled road section and the i-th typical road section, Wi,hAnd the speed weight of the ith typical road section corresponding to the h-th unexplored road section is shown.
Optionally, the road impedance corresponding to the h-th non-sampled road section is calculated according to the speed weight corresponding to the h-th non-sampled road section, and the specific formula is as follows:
wherein, length* hRepresents the road impedance, length, corresponding to the h-th unsampled road sectionhRepresents the road length, w, corresponding to the h-th unsampled road section* hRepresents the speed limit value W corresponding to the h-th non-sampled road sectionhAnd representing the speed weight corresponding to the h-th non-sampled road section.
Optionally, the planning of the driving path according to the road impedance corresponding to each non-sampled road segment specifically includes:
and selecting the road section with the minimum road impedance corresponding to each non-sampled road section as the driving path.
The invention also provides a path planning system, which comprises:
the typical road section determining module is used for determining n typical road sections;
the assignment module is used for enabling h to be 1;
the similarity determining module is used for calculating the similarity between the h-th non-sampled road section and each typical road section based on a fuzzy reasoning method;
the speed weight determining module is used for calculating the speed weight corresponding to the h-th non-sampling road section according to the similarity of the h-th non-sampling road section and each typical road section;
the road impedance determination module is used for calculating the road impedance corresponding to the h-th non-sampled road section according to the speed weight corresponding to the h-th non-sampled road section;
the judging module is used for judging whether h is smaller than K or not; if h is smaller than K, making h equal to h +1, and returning to the similarity determination module; if h is greater than or equal to K, executing a planning module; k is the total number of the non-sampled road sections;
and the planning module is used for planning the driving path according to the road impedance corresponding to each non-sampled road section.
Optionally, the typical road segment determining module further includes:
the acquisition unit is used for acquiring a plurality of sample road sections; the sample road segment comprises m road attribute values and speed weights;
the training unit is used for classifying the plurality of sample road sections by using a random forest method and training a prediction model;
the first speed weight calculation unit is used for calculating the first speed weight of each non-sampling road section according to the prediction model;
and the comparison unit is used for determining n typical road sections according to the first speed weight of each non-sampling road section and the speed weights of the plurality of sample road sections.
Optionally, the similarity between the h-th non-sampled road segment and each typical road segment is calculated based on a fuzzy inference method, and a specific formula is as follows:
wherein, Pj,hJ-th road attribute value, S, representing h-th unsampled road segmenti,hRepresenting the similarity, k, of the h-th unsampled road segment to the i-th typical road segment1And w1Denotes a correction parameter, Pjt,hAnd j represents the j-th road attribute value of each typical road section corresponding to the h-th unexplored road section, and m is the number of the road attribute values.
Optionally, the speed weight corresponding to the h-th non-sampled road section is calculated according to the similarity between the h-th non-sampled road section and each typical road section, and the specific formula is as follows:
wherein, WhRepresents the speed weight corresponding to the h-th non-sampled road section, Si,hRepresents the similarity of the h-th non-sampled road section and the i-th typical road section, Wi,hAnd the speed weight of the ith typical road section corresponding to the h-th unexplored road section is shown.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
the invention provides a path planning method and a system, wherein the method comprises the following steps: firstly, determining n typical road sections; then h is 1; calculating the similarity between the h-th non-sampled road section and each typical road section based on a fuzzy reasoning method; calculating the speed weight corresponding to the h-th non-sampled road section according to the similarity of the h-th non-sampled road section and each typical road section; calculating the road impedance corresponding to the h-th non-sampled road section according to the speed weight corresponding to the h-th non-sampled road section; until h is equal to K, wherein K is the total number of the non-sampled road sections; and finally planning a driving path according to the road impedance corresponding to each non-sampled road section. The invention effectively avoids steep slopes and road sections with narrow visual fields based on the principle that the higher the road impedance is, the lower the safety is, and reduces the road passing chances with poor safety, thereby planning the driving path for safe trip of the driver on the mountain road.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a flowchart of a path planning method according to embodiment 1 of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a path planning method and a system to plan a safe driving path.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
Example 1
Fig. 1 is a flowchart of a path planning method according to embodiment 1 of the present invention, and as shown in fig. 1, the path planning method includes:
s1: n representative road segments are determined.
S2: let h equal to 1.
S3: and calculating the similarity between the h-th non-sampled road section and each typical road section based on a fuzzy inference method.
S4: and calculating the speed weight corresponding to the h-th non-sampled road section according to the similarity of the h-th non-sampled road section and each typical road section.
S5: and calculating the road impedance corresponding to the h-th non-sampled road section according to the speed weight corresponding to the h-th non-sampled road section.
S6: judging whether h is smaller than K; if h is less than K, let h be h +1, and return to "S3"; if h is greater than or equal to K, "S7" is performed; wherein K is the total number of the non-sampled road sections.
S7: and planning a driving path according to the road impedance corresponding to each non-sampled road section.
In the embodiment of the present invention, the determining n typical road segments specifically includes:
s11: collecting a plurality of sample road sections; the sample road segment includes m road attribute values and speed weights. In the embodiment of the present invention, a total of 242 sample road segments are collected, where each sample road segment includes 4 road attribute values, and the road attribute values include: road grade factor, visual field factor, road grade factor and road waviness factor. The samples were taken as in table 1.
TABLE 1
S12: and classifying the plurality of sample road sections by using a random forest method and training a prediction model. Wherein the road attribute value is an independent variable and the speed is a dependent variable. A partial sample link data example is shown in table 2.
Table 2 example of partial sample link data selection
S13: and calculating the first speed weight of each non-sampling road section according to the prediction model.
S14: determining n typical road sections according to the first speed weight of each non-sampling road section and the speed weights of a plurality of sample road sections; specifically, the speed weight of each sample road section is compared with the first speed weight of each non-sampled road section, and each sample road section within a set range is selected as a typical road section.
In the embodiment of the present invention, the similarity between the h-th non-sampled road segment and each typical road segment is calculated based on a fuzzy inference method, and a specific formula is as follows:
wherein, Pj,hJ-th road attribute value, S, representing h-th unsampled road segmenti,hRepresenting the similarity, k, of the h-th unsampled road segment to the i-th typical road segment1And w1Denotes a correction parameter, Pjt,hAnd j represents the j-th road attribute value of each typical road section corresponding to the h-th unexplored road section, and m is the number of the road attribute values.
In the embodiment of the present invention, the speed weight corresponding to the h-th non-sampled road section is calculated according to the similarity between the h-th non-sampled road section and each typical road section, and a specific formula is as follows:
wherein, WhRepresents the speed weight corresponding to the h-th non-sampled road section, Si,hRepresents the similarity of the h-th non-sampled road section and the i-th typical road section, Wi,hAnd the speed weight of the ith typical road section corresponding to the h-th unexplored road section is shown.
In the embodiment of the present invention, the road impedance corresponding to the h-th non-sampled road section is calculated according to the speed weight corresponding to the h-th non-sampled road section, and the specific formula is as follows:
wherein, length* hRepresents the road impedance, length, corresponding to the h-th unsampled road sectionhRepresents the road length, w, corresponding to the h-th unsampled road section* hRepresents the speed limit value W corresponding to the h-th non-sampled road sectionhAnd representing the speed weight corresponding to the h-th non-sampled road section.
In the embodiment of the present invention, the planning of the driving path according to the road impedance corresponding to each non-sampled road segment specifically includes:
and selecting the road section with the minimum road impedance corresponding to each non-sampled road section as the driving path.
Example 2
The invention also provides a path planning system, which comprises:
and the typical road section determining module is used for determining n typical road sections.
And the assignment module is used for enabling h to be 1.
And the similarity determining module is used for calculating the similarity between the h-th non-sampled road section and each typical road section based on a fuzzy reasoning method.
And the speed weight determining module is used for calculating the speed weight corresponding to the h-th non-sampled road section according to the similarity of the h-th non-sampled road section and each typical road section.
And the road impedance determination module is used for calculating the road impedance corresponding to the h-th non-sampled road section according to the speed weight corresponding to the h-th non-sampled road section.
The judging module is used for judging whether h is smaller than K or not; if h is smaller than K, making h equal to h +1, and returning to the similarity determination module; if h is greater than or equal to K, executing a planning module; wherein K is the total number of the non-sampled road sections.
And the planning module is used for planning the driving path according to the road impedance corresponding to each non-sampled road section.
In an embodiment of the present invention, the typical road segment determining module further includes:
the acquisition unit is used for acquiring a plurality of sample road sections; the sample road segment comprises m road attribute values and speed weights;
the training unit is used for classifying the plurality of sample road sections by using a random forest method and training a prediction model;
the first speed weight calculation unit is used for calculating the first speed weight of each non-sampling road section according to the prediction model;
the comparison unit is used for determining n typical road sections according to the first speed weight of each non-sampling road section and the speed weights of a plurality of sample road sections; specifically, the speed weight of each sample road section is compared with the first speed weight of each non-sampled road section, and each sample road section within a set range is selected as a typical road section.
In the embodiment of the present invention, the similarity between the h-th non-sampled road segment and each typical road segment is calculated based on a fuzzy inference method, and a specific formula is as follows:
wherein, Pj,hJ-th road attribute value, S, representing h-th unsampled road segmenti,hRepresenting the similarity, k, of the h-th unsampled road segment to the i-th typical road segment1And w1Denotes a correction parameter, Pjt,hAnd j represents the j-th road attribute value of each typical road section corresponding to the h-th unexplored road section, and m is the number of the road attribute values.
In the embodiment of the present invention, the speed weight corresponding to the h-th non-sampled road section is calculated according to the similarity between the h-th non-sampled road section and each typical road section, and a specific formula is as follows:
wherein, WhRepresents the speed weight corresponding to the h-th non-sampled road section, Si,hRepresents the similarity of the h-th non-sampled road section and the i-th typical road section, Wi,hAnd the speed weight of the ith typical road section corresponding to the h-th unexplored road section is shown.
The invention mainly analyzes influence factors (road attribute values) influencing the driving safety of the mountainous area road, provides a weight assignment method considering the driving safety based on the principle that the lower the safety is, the higher the road impedance is, and realizes the planning of the mountainous area path according to the road impedance. According to the method, the influence factor data and the safe driving speed data of a typical road section are sampled, the classification mapping relation between the safe driving speed and the influence factors is constructed based on the thought of random forest classification, the problem that a weight assignment function is constructed directly through the influence factors is solved, the fuzzy membership degree of a fuzzy inference method is applied to weight assignment of a non-sampled road section sample, and the result is more accurate and reasonable than that of a direct sampling random forest classification method. Example verification results show that the path recommended by the evaluation method considering the safety weight, provided by the invention, can effectively avoid steep slopes and narrow-view road sections, and reduce the road passing chance with poor safety, so that scientific reference is provided for safe travel of the driver on the mountain road. The invention judges the safety of the driving road section and obtains a more reasonable driving path. The selection of the road attribute value is open, factors influencing the driving safety can be incorporated into the road attribute value according to the actual condition of the research area, and the clearer the analysis of the factors influencing the driving safety of the road is, the safer and more reasonable path can be obtained. And aiming at different types of mountain road characteristics, factors which influence safety more comprehensively are disclosed, and further intensive research is worth.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
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