CN106651231B - Path planning method and path planning device - Google Patents

Abstract

The invention provides a path planning method and a path planning device. The method plans a distribution route of vehicles in a path including a yard and a plurality of stations including a first type of station having a limitation on a service period and a second type of station having no limitation on the service period, the path planning method being characterized by comprising: and a first route generation step of forming a first temporary distribution route by each first-type station of at least one first-type station waiting to join the distribution route and the yard, selecting the first temporary distribution route which meets the time period limit of the first-type station and has the shortest travel time as the first route, forming a second temporary distribution route by each second-type station of at least one second-type station waiting to join the distribution route and the yard under the condition that the first temporary distribution route which meets the time period limit of the first-type station does not exist, and selecting the second temporary distribution route which has the shortest travel time as the first route.

Description

Path planning method and path planning device

Technical Field

The present invention relates to a route planning method and a route planning device for vehicles in logistics distribution, and more particularly to a route planning method and a route planning device that take into account time zone restrictions (hereinafter, sometimes referred to as "time restrictions") of customer sites.

Background

In the related art, in industries such as cash dispensing at cash dispensers, goods dispensing at vending machines, oil dispensing at gas stations, and garbage collection, a delivery vehicle is generally returned to a yard after passing through a plurality of customers (corresponding to "stations" in the present invention) along a certain travel route (also referred to as a "travel route") after departing from the yard (also referred to as a "delivery center"). A vehicle is generally responsible for the delivery of all stations on a travel path. When planning the travel route, the travel route of the vehicle is minimized, the cost is minimized, the time is minimized, and the vehicles used for distribution are minimized, in general, when certain limiting conditions (such as a route travel time limit, a vehicle load amount, a demand amount of goods required for a station, a time window limit, and the like) are satisfied.

FIG. 1 is a schematic diagram showing vehicle path planning for multiple stations in a single yard. Fig. 1 shows 1 yard, 10 stations, and 4 delivery vehicles. Wherein the black circle (●) represents the yard, the open circle (O) represents the station, and the vehicle mark

The black circles representing delivery vehicles, including "0" also represent the yard, and the numbers 1 to 10 in the open circles represent different stations.

As shown in fig. 1, by performing the route planning of the vehicle, a vehicle is responsible for the distribution of a travel route of the yard → the station 6 → the station 5 → the station 7 → the yard; the second vehicle is responsible for the delivery of the driving path of the yard → station 1 → station 3 → station 2 → station 4 → yard; the third vehicle is responsible for the distribution of the travel path of the yard → station 8 → station 9 → station 10 → yard.

In an actual multi-station vehicle path in a single yard, in addition to the above-mentioned route time limit, vehicle load, station demand, etc., some customer stations also have requirements for specific service times (i.e., delivery times), such as some customers (i.e., customer stations) requiring vehicles to arrive between 9:00-10:00 a.m. morning and some customers requiring vehicles to arrive between 8:30-10:00 a.m. morning.

In order to solve the problem that a client station has a requirement on specific service time, patent document CN103699982A proposes a logistics distribution control method with a soft time window, in which an optimized scheduling model is first established, an objective function is established with the lowest transportation cost, and then a path is planned by using a heuristic algorithm.

Patent document CN104036379A proposes a method for solving the problem of time-varying associated logistics transportation vehicle path with hard time window, which first establishes a mathematical model of the problem of time-varying associated logistics transportation vehicle path with hard time window constraint, and then designs a tabu search algorithm to solve the problem.

Disclosure of Invention

In patent document CN103699982A, from the content point of view, it is not required that the vehicle must arrive within a customer-specified time period, and if the vehicle does not arrive within the specified time period, a penalty value is given to the scheme of this path to reduce the possibility of the scheme being selected. However, in the actual operation process, if the vehicle can not arrive within the time period required by the customer, the normal operation of the customer is affected. For example, in the case of bank cash delivery, if the delivery company is unable to dispense the bank notes in a timely manner, access to the cash may be compromised.

The invention of patent document CN104036379A, although capable of satisfying the time requirement of the customer site, has the following problems. First, the invention requires setting many variable parameters such as maximum number of iterations, size of tabu table, how to get initial route, how to set tabu object and how to get neighborhood solution, etc. This means that for a better solution, these parameters need to be changed each time the application scene changes, and for those without professional background, it is basically impossible to adjust these parameters, which greatly reduces the universality of the algorithm. Second, during the delivery process, if the delivery vehicle arrives at the current customer at a time earlier than the earliest time window requested by the customer, the vehicle needs to wait for the difference between the time of the current customer's time window and the time the vehicle arrives at the customer. If this happens and the waiting time is extremely long, it means that the delivery vehicle needs to find a place to stop waiting, but in some cities, especially in some big cities, it is difficult to find a place to stop during the peak parking period, and even if the place to stop can be found, the parking fee needs to be paid in some cases, which not only increases the delivery cost, but also increases the invalid running time of the vehicle. Third, if no wait time is set, the method may fall into a non-converged state, i.e., a delivery scenario that does not meet all customer site time constraints is not achieved.

In view of the above problems, the present invention provides a path planning method and a path planning apparatus that do not require setting of complicated parameters, are easy to use, and take into account the time period limitation of the customer site.

A route planning method of an aspect of the present invention is a route planning method for planning a delivery route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning method being characterized by comprising: a first route generation step of forming a first temporary distribution route by each of the first type stations, which are to be added to the distribution route, and the yard, selecting the first temporary distribution route, which satisfies a time period limitation of the first type stations and has the shortest travel time, as the first route, and forming a second temporary distribution route by each of the second type stations, which is to be added to the distribution route, and the yard, when there is no first temporary distribution route satisfying the time period limitation of the first type stations, and selecting the second temporary distribution route, which has the shortest travel time, as the first route.

A second aspect of the present invention is a path planning method according to the first aspect, including: a second route generation step of adding each first-type station, which is waiting to be added to at least one first-type station in the distribution routes, to the end of the first route or forming a third temporary distribution route based on the end of the temporary distribution route generated by the first route, and selecting the third temporary distribution route which meets the time period limit of the first-type station and has the shortest driving time as a second route, and if a third temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the tail end of the first route or the tail end of a temporary distribution route generated based on the first route to form a fourth temporary distribution route, and selecting the fourth temporary distribution route with the shortest driving time as the second route.

A path planning method according to a third aspect of the present invention is the path planning method according to the first aspect, including: a second route generation step of adding each of the first type stations waiting to be added to at least one of the first type stations in the distribution routes to a third temporary distribution route after a last first type station in the first routes or after a last first type station in temporary distribution routes generated based on the first routes, respectively (wherein "after the last first type station in the first routes or after the last first type station in temporary distribution routes generated based on the first routes" means a position of adding a first type station, specifically, three positions are included, that is, between the last first type station and a second type station, between each second type station, and between a second type station and a yard), selecting the third temporary distribution route which satisfies a time period limit of the first type station and has a shortest travel time as the first route, and in the case that a third temporary distribution route which meets the time period limit of the first type of stops does not exist, respectively joining each second type of stop waiting to join at least one second type of stop in the distribution routes after the last first type of stop in the first routes or after the last first type of stop in the temporary distribution routes generated based on the first routes to form a fourth temporary distribution route, and selecting the fourth temporary distribution route with the shortest driving time as the second route.

A route planning method of a fourth aspect of the present invention is a route planning method for planning a delivery route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning method comprising: a first route generation step of configuring, with the yard, each of at least one site pair of 2 sites of the first type among the distribution routes as a first temporary distribution route, selecting, as a first route, the first temporary distribution route that satisfies a time period limit for the first type of sites and has a maximum saving value, configuring, with the yard, each of at least one site pair of 1 site of the first type and 1 site of the second type among the distribution routes as a second temporary distribution route in the case where there is no first temporary distribution route that satisfies a time period limit for the first type of sites, selecting, as the first route, the second temporary distribution route that satisfies a time period limit for the first type of sites and has a maximum saving value, and selecting, in the case where there is no second temporary distribution route that satisfies a time period limit for the first type of sites, and respectively forming a third temporary distribution route by each station pair in at least one station pair consisting of 2 stations of the second type in the distribution routes and the yard, and selecting the third temporary distribution route with the largest saving value as the first route, wherein the saving value is the difference between the total time required for respectively distributing the 2 stations in the station pair and the total time required for distributing the 2 stations together in the station pair.

A path planning method according to a fifth aspect of the present invention is the path planning method according to the fourth aspect, including: a second route generation step of adding each first-type station of at least one first-type station waiting to be added to the distribution route to the end of the first route or forming a fourth temporary distribution route based on the end of the temporary distribution route generated by the first route, and selecting the fourth temporary distribution route which meets the time period limit of the first-type station and has the shortest driving time as a second route, and in the case that a fourth temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fifth temporary distribution route, and selecting the fifth temporary distribution route with the shortest driving time as the second route.

A path planning method according to a sixth aspect of the present invention is the path planning method according to the fourth aspect, including: a second route generation step of adding each first-type station of at least one first-type station waiting to be added to the distribution routes to a fourth temporary distribution route after a last first-type station of the first routes or a temporary distribution route generated based on the first routes, selecting the fourth temporary distribution route satisfying a time period limit of the first-type station and having a shortest travel time as a second route, and in the case where there is no fourth temporary distribution route satisfying the time period limit of the first-type station, adding each second-type station of at least one second-type station waiting to be added to the distribution routes to a last first-type station of the first routes or forming a fifth temporary distribution route after a last first-type station of the temporary distribution routes generated based on the first routes And selecting the fifth temporary distribution route with the shortest travel time as the second route.

A seventh aspect of the present invention is the path planning method according to any one of the first to sixth aspects, including: a travel time acquisition step of acquiring, before the first route generation step, travel times between the yard and each of the stations and between the plurality of stations, the travel times being used for calculating the travel time of the distribution route.

A path planning method according to an eighth aspect of the present invention is the path planning method according to any one of the first to sixth aspects, including: and a third route generation step of selecting one or more first-class stations to form a third route with the yard on the premise of meeting the time period limit of the first-class stations only when the first-class stations waiting to join the distribution route exist after the second route generation step.

A ninth aspect of the present invention provides the path planning method according to any one of the first to sixth aspects, wherein the travel time of the first route and the second route is less than a preset travel time limit value.

A route planning method according to a tenth aspect of the present invention is the route planning method according to the eighth aspect, wherein the travel time of the third route is less than a preset travel time limit value.

An eleventh aspect of the present invention provides a route planning apparatus that plans a distribution route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning apparatus characterized by comprising: and a first route generation module configured to form a first temporary distribution route by each of the first type stations waiting to join the distribution route and the yard, select the first temporary distribution route satisfying a time period limitation of the first type stations and having a shortest travel time as a first route, form a second temporary distribution route by each of the second type stations waiting to join the distribution route and the yard if there is no first temporary distribution route satisfying the time period limitation of the first type stations, and select the second temporary distribution route having a shortest travel time as the first route.

A path planning device according to a twelfth aspect of the present invention is the path planning device according to the eleventh aspect, including: a second route generation module, configured to join each of the first type stops waiting to join the distribution routes to an end of the first route or to form a third temporary distribution route based on an end of a temporary distribution route generated by the first route, and select the third temporary distribution route that satisfies a time period limit of the first type stops and has a shortest travel time as a second route, and if a third temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution routes to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fourth temporary distribution route, and selecting the fourth temporary distribution route with the shortest driving time as the second route.

A path planning device according to a thirteenth aspect of the present invention is the path planning device according to the eleventh aspect, including: a second route generation module, configured to join each of the first type sites waiting to join the distribution routes to a third temporary distribution route after a last first type site in the first routes or a last first type site in temporary distribution routes generated based on the first routes, select the third temporary distribution route satisfying a time period limit of the first type sites and having a shortest travel time as a second route, and join each of the second type sites waiting to join the distribution routes to a fourth temporary distribution route after a last first type site in the first routes or after a last first type site in temporary distribution routes generated based on the first routes in a case where there is no third temporary distribution route satisfying the time period limit of the first type sites And selecting the fourth temporary distribution route with the shortest travel time as the second route.

A fourteenth aspect of the present invention provides a route planning apparatus that plans a distribution route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning apparatus characterized by comprising: a first route generation module that configures each of at least one site pair of 2 sites of a first type to be added to the distribution routes as a first temporary distribution route with the yard, selects the first temporary distribution route that satisfies a time zone limitation of the first type and has a maximum saving value as a first route, configures each of at least one site pair of 1 site of the first type and 1 site of the second type to be added to the distribution routes as a second temporary distribution route with the yard when there is no first temporary distribution route that satisfies a time zone limitation of the first type, selects the second temporary distribution route that satisfies a time zone limitation of the first type and has a maximum saving value as a first route, and if there is no second temporary distribution route that satisfies a time zone limitation of the first type, and respectively forming a third temporary distribution route by each station pair in at least one station pair consisting of 2 stations of the second type in the distribution routes and the yard, and selecting the third temporary distribution route with the largest saving value as the first route, wherein the saving value is the difference between the total time required for respectively distributing the 2 stations in the station pair and the total time required for distributing the 2 stations together in the station pair.

A path planning device according to a fifteenth aspect of the present invention is the path planning device according to the fourteenth aspect, including: a second route generation module, configured to join each of the first type stops waiting to join the distribution routes to an end of the first route or to form a fourth temporary distribution route based on an end of a temporary distribution route generated by the first route, and select the fourth temporary distribution route that satisfies a time period limit of the first type stops and has a shortest travel time as a second route, and in the case that a fourth temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fifth temporary distribution route, and selecting the fifth temporary distribution route with the shortest driving time as the second route.

A path planning device according to a sixteenth aspect of the present invention is the path planning device according to the fourteenth aspect, comprising: a second route generation module, configured to join each of the first type sites waiting to join the distribution routes after a last first type site in the first routes or to form a fourth temporary distribution route after a last first type site in temporary distribution routes generated based on the first routes, select, as a second route, the fourth temporary distribution route that satisfies a time period limitation of the first type sites and has a shortest travel time, and in a case where there is no fourth temporary distribution route that satisfies the time period limitation of the first type sites, join each of the second type sites waiting to join the distribution routes after a last first type site in the first routes or form a fifth temporary distribution route after a last first type site in temporary distribution routes generated based on the first routes And selecting the fifth temporary distribution route with the shortest travel time as the second route.

A route planning device according to a seventeenth aspect of the present invention is the route planning device according to any one of the eleventh to sixteenth aspects, including: and a travel time acquisition module that acquires travel times between the yard and each of the stations and between the plurality of stations before the first route generation module generates the first route, the travel times being used to calculate the travel time of the distribution route.

A route planning device according to an eighteenth aspect of the present invention is the route planning device according to any of the eleventh to sixteenth aspects, including: and a third route generation module, configured to select one or more first type stations to form a third route with the yard on the premise that a time period limit of the first type stations is met, in a case where there is only the first type stations waiting to join the distribution route after the second route generation module generates the second route.

Technical effects

According to the path planning method and the path planning device of the invention, the following beneficial technical effects can be obtained: the distribution route can be automatically planned, and the labor cost is saved; complex parameters do not need to be set, so that the use is convenient; the method can meet the distribution requirements of all client sites with time section limitation, ensure the normal operation of the client sites and improve the credit of distribution companies; because the waiting time of the vehicle is not required to be set, the vehicle does not need to be stopped midway, the invalid operation of the vehicle is reduced, and the distribution cost is reduced.

Drawings

FIG. 1 is a schematic diagram showing vehicle path planning for multiple stations in a single yard.

Fig. 2 is a schematic diagram showing the limitation of a service period by a client station in an application scenario of the present invention.

Fig. 3 is a flow chart of a path planning method of the present invention.

Fig. 4 is a schematic diagram of a classification process for classifying the respective sites into the first-class site and the second-class site.

Fig. 5 is a schematic diagram showing a travel time matrix between the yard and each station and between all stations.

Fig. 6 is a flowchart of generating an initial delivery route (embodiment 1).

Fig. 7(a) is a schematic diagram showing the arrival and required time of the delivery vehicle from the yard to each of the first type candidate stations at a predetermined time. Fig. 7(b) is a schematic diagram showing that the first type stations conforming to the time zone limit respectively form temporary initial routes with the yard. Fig. 7(c) shows the initial route generated last in the case where there is a first type station whose arrival time meets the time period limit among the first type candidate stations.

Fig. 8(a) is a schematic diagram showing the departure from the yard to each of the second type candidate stations at a predetermined time. Fig. 8(b) is a schematic diagram showing that each of the second type candidate stations forms a temporary initial route with the yard. Fig. 8(c) shows the initial route generated last in the case where there is no first-type station whose arrival time meets the time period limit among the first-type candidate stations.

Fig. 9 is a flowchart of generating a complete route (example 1).

Fig. 10(a) to 10(j) are schematic diagrams of generation of a complete route (example 1).

Fig. 11 shows all the complete routes finally generated (example 1).

Fig. 12(a) to 12(b) are diagrams for explaining the meaning of saving values.

Fig. 13 is a flowchart of generating an initial delivery route (embodiment 2).

Fig. 14(a) to 14(d) are schematic views showing the first type of candidate station pairs satisfying the time zone restriction to form an initial route with the yard (embodiment 2).

Fig. 15(a) to 15(e) are schematic views showing that a station pair consisting of one first-type candidate station and one second-type candidate station satisfying the time zone restriction forms an initial route with the yard (embodiment 2).

Fig. 16(a) to 16(c) show the travel time required for each of 2 second-type candidate stops to form a distribution route with the yard, and the travel time required for each of the 2 second-type candidate stops to form a distribution route with the yard, and fig. 16(d) shows the determined initial route (example 2).

Fig. 17(a) shows a case where a candidate site is added to the initial route shown in fig. 14(d), fig. 17(b) shows a case where a candidate site is added to the initial route shown in fig. 15(e), and fig. 17(c) shows a case where a candidate site is added to the initial route shown in fig. 16(d) (example 2).

Fig. 18 is a flowchart of generating a complete route (embodiment 2).

Fig. 19(a) to 19(e) are (one of) schematic diagrams of generating a complete route in example 2.

Fig. 20(a) to 20(e) are (two) schematic diagrams illustrating the generation of a complete route in example 2.

Fig. 21 shows all the complete routes finally generated (example 2).

FIG. 22 is a flow chart of path planning for a first type of candidate site after a complete delivery route has been generated.

Fig. 23(a) and 23(b) are schematic diagrams of a first type of candidate station and a yard constituting a distribution route.

Fig. 24 is a schematic diagram showing the temporary route generated in step 55 of the flowchart of fig. 22.

Detailed Description

Preferred embodiments for carrying out the present invention will be described below. The following embodiments are merely exemplary. The present invention is not limited to the following embodiments.

Before describing the path planning method of the present invention, an application scenario for multi-site delivery in a single yard is first set up. Fig. 2 is a schematic diagram showing a limitation of a client site (hereinafter, simply referred to as "site") to a service period in an application scenario of the present invention.

In fig. 2, it is assumed that there are 10 sites to be dispatched, with 4 sites having limited requirements for service periods. The "serial number" in fig. 2 indicates each station. For example, the number 1 indicates the station 1, and the number 2 indicates the station 2. As shown in FIG. 2, site 1 requires service during the time period 8:00-9:00, site 5 requires service during the time period 10:00-11:00, site 7 requires service during the time period 11:30-12:00, and site requires service during the time period 9:00-10: 00. In fig. 2, "/" indicates no limitation on the service period.

In this specification, a site that has a limited demand for a service period is referred to as a first-type site, a site that has no limited demand for a service period is referred to as a second-type site, a site that is waiting to join a delivery route (i.e., a site that has not yet joined the delivery route) is referred to as a candidate site, and a first-type site and a second-type site that are waiting to join the delivery route are referred to as a first-type candidate site and a second-type candidate site, respectively.

In the scenario of the route planning method of the present invention, the constraint is that the travel time of each delivery route should not exceed 4 hours (240 minutes), i.e., the vehicle should not exceed 4 hours from departure to return to the yard. Of course, the person skilled in the art may adjust the limiting conditions according to the situation, for example, the travel time of each delivery route should not exceed 3.5 hours. In addition, the load of the vehicle, the demand of each station, the service time of the vehicle at the station, the traffic congestion condition, and the like may affect the travel time in the route planning method of the present invention, and the effects of these factors are not considered in the present specification in order to make the present invention easier to understand.

In addition, in the scenario of the route planning method of the present invention, the time for the delivery vehicle to depart from the yard is set to 8: 00. However, the actual departure time of the delivery vehicle from the yard is not limited to 8:00, and those skilled in the art can set the departure time arbitrarily according to the actual situation, and may set the departure time to other times such as 8:30, 9:00, and the like.

The application scenario described above is a simplified version scenario set on the basis of not affecting the main logic of the path planning method of the present invention, but the present invention is not limited to this scenario, and may also be applied to other scenarios with limited conditions, such as vehicle cargo capacity limitation, site demand limitation, and any combination of the above.

Fig. 3 is a flow chart of a path planning method of the present invention. First, the sites are divided into the first kind of sites and the second kind of sites according to whether there is a requirement for a limited service period (step 1). Next, an appropriate station and yard are selected to form an initial route (step 2). And then, adding other stations into the initial route to form a complete route on the premise of meeting the limiting conditions (step 3). It is then determined whether there are any remaining first type sites that have not joined the initial route and the full route (step 4). If yes, then path planning is carried out on the rest first type stations (step 5), and if no, path planning is finished.

Fig. 4 is a schematic diagram of a classification process of classifying the respective sites into the first kind of sites and the second kind of sites according to whether there is a requirement for a limitation on the service period (i.e., the delivery period). In the classification processing, a station having a restriction on a service period is regarded as a first class station, a station having no restriction on a service period is regarded as a second class station, and the first class stations are sorted according to the earliest arrival time required by the stations.

Reference numerals 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 in fig. 4 denote delivery stations, where the stations with time slot limitation are 1, 5, 7, 9, station 1 requires delivery during 8:00-9:00, station 5 requires delivery during 10:00-11:00, station 7 requires delivery during 11:30-12:00, station 9 requires delivery during 9:00-10:00, and 2, 3, 4, 6, 8, 10 do not require delivery time. The first type of stations are ordered as 1, 9, 5 and 7 according to the earliest arrival time required by the stations.

Before the initial route and the complete route are generated, the travel time between the yard and each station and between all stations is also obtained, and the matrix obtained by combining the travel time is called a travel time matrix. Fig. 5 is a schematic diagram showing a travel time matrix (unit is 10 minutes) between the yard and each station and between all stations. In fig. 5, 0 among the numbers enclosed by the lower left dashed line frame represents a departure yard, 1 to 10 represent departure stations, 0 among the numbers enclosed by the upper right dashed line frame represents a destination yard (i.e., arrival yard), and 1 to 10 represent destination stations (i.e., arrival stations). According to fig. 5, for example, if the destination station is 7 from the station 3, the travel time is 30 minutes. Assuming that the destination station is 3 on the day of distribution from station 7, the travel time is 60 minutes.

In actual life, due to influences of factors such as early and high peaks, late and high peaks, weather changes, traffic accidents, traffic control, large activities and the like, the driving speed of a vehicle actually changes dynamically, so that the driving time and speed of each road section in a road network also change correspondingly. However, in this specification, for the sake of easy understanding of the description, it is assumed that the travel time from the yard to each station and between stations is constant throughout the day, as shown in fig. 5. For example, the travel time from the station 3 to the station 7 is 30 minutes in each day, and the travel time from the station 7 to the station 3 is 60 minutes in each day.

The following describes a method for planning a travel route (also referred to as a "travel route") in the application scenario described above with reference to embodiments 1 to 3.

Example 1

Fig. 6 is a flowchart of generating an initial delivery route (hereinafter simply referred to as "initial route") in embodiment 1. The time required to reach each candidate site of the first type from the yard is first acquired (step 11).

Fig. 7(a) is a schematic diagram showing the arrival and required time of the delivery vehicle from the yard to each of the first type candidate stations at a predetermined time (here, 8: 00). As shown in fig. 7(a), the delivery vehicles arrive at station 1 after 30 minutes from yard 0, the delivery vehicles arrive at station 5 after 60 minutes from yard 0 at 8:00, the delivery vehicles arrive at station 7 after 40 minutes from yard 7, and the delivery vehicles arrive at station 9 after 110 minutes from yard 0. The time required from the yard 0 to each station 1 can be obtained from the travel time matrix.

It is then determined whether there is a station whose arrival time meets the time period limit among the first-type candidate stations (i.e., stations 1, 5, 7, 9) (step 12). The arrival time of each first-type station and the time period limit (may also be referred to as "limit time period") for each first-type station are set forth in table 1 below.

[ Table 1]

As shown in Table 1 above, the time to site 1 (8:30) is within its limit time period (8:00-9:00), the time to site 9 (9:50) is also within its limit time period (9:00-10:00), and the time to sites 5, 7 is outside of the limit time period. It is thus determined that there are first type stations 1, 9 whose arrival times meet the time period limit among the first type candidate stations.

If it is determined that there is a first-class station whose arrival time matches the time zone limit among the first-class candidate stations, the first-class station matching the time zone limit and the yard form a temporary initial route (step 13). Fig. 7(b) is a schematic diagram showing that the first type stations conforming to the time zone limit respectively form temporary initial routes with the yard.

As shown in fig. 7(b), in the provisional initial route composed of the station 1 and the yard 0, the delivery vehicle arrives at the station 1 after 30 minutes from the yard 0 at a predetermined time (8:00), and returns to the yard 0 after 60 minutes from the station 1, and the total travel time of the provisional initial route is 90 minutes. In the provisional initial route composed of the stop 9 and the yard 0, the delivery vehicles arrive at the stop 9 after 110 minutes from the yard 0 at a predetermined time (8:00), and return to the yard 0 after 70 minutes from the stop 9, and the total travel time of the provisional initial route is 180 minutes (see table 2 below).

[ Table 2]

Since the travel time of the provisional initial route (0 → 1 → 0) is shortest, the route having the shortest travel time is selected as the initial route (step 14). Fig. 7(c) shows the initial route generated last in the case where there is a first type station whose arrival time meets the time period limit among the first type candidate stations.

The method of generating the initial route in the case where there is a first type station whose arrival time meets the time period limit among the first type candidate stations has been described above. Next, a method of generating an initial route when there is no first-type station whose arrival time matches the time period limit among the first-type candidate stations will be described.

If there is no first-class station whose arrival time matches the time zone limit among the first-class candidate stations, the second-class candidate stations and the yard form a temporary initial route (step 15). Fig. 8(a) is a schematic diagram showing the transition from the yard to each of the second type candidate stations at a predetermined time (8: 00). Fig. 8(b) is a schematic diagram showing that each of the second type candidate stations forms a temporary initial route with the yard.

As shown in fig. 8(b), in the provisional initial route composed of the stop 2 and the yard 0, the delivery vehicle arrives at the stop 2 after 60 minutes from the yard 0 and returns to the yard 0 after 70 minutes from the stop 2, and the total travel time of the provisional initial route (0 → 2 → 0) is 130 minutes. Also, the travel time of the provisional initial route (0 → 3 → 0) is 100 minutes; the travel time of the provisional initial route (0 → 4 → 0) is 120 minutes; the travel time of the provisional initial route (0 → 6 → 0) was 70 minutes; the travel time of the provisional initial route (0 → 8 → 0) is 180 minutes; the travel time of the provisional initial route (0 → 10 → 0) is 170 minutes (see table 3 below).

[ Table 3]

Since the travel time of the provisional initial route (0 → 6 → 0) is shortest, the route having the shortest travel time is selected as the initial route (step 16). Fig. 8(c) shows the initial route generated last in the case where there is no first-type station whose arrival time meets the time period limit among the first-type candidate stations.

The method for generating a complete route will be described below with reference to fig. 9 to 11. FIG. 9 is a flow chart for generating a complete route. Fig. 10(a) to 10(j) are schematic diagrams of generation of a complete route. Fig. 11 shows all the complete routes that are finally generated.

First, it is determined whether there is a station without a time limit that is not joined to the delivery route, that is, whether there is a second type candidate station waiting to be joined to the delivery route (step 21). If there is a second type of candidate station, an initial route is generated in accordance with the method shown in steps 11 to 15 (step 22). In the case where there is no second-type candidate station, the generation of the complete route is ended.

After step 22, a temporary distribution route is determined, and the first type candidate stops are added to the end of the temporary distribution route (i.e., after the stops in the temporary distribution route) (step 23), respectively, to form a new route. When the temporary delivery route is determined in step 23, the initial route generated in step 22 is initially selected as the temporary delivery route. For example, when the initial route is 0 → 1 → 0 and one of the first type candidate sites 5 is added to the end of the initial route, the new route is 0 → 1 → 5 → 0. When the initial route is 0 → 6 → 0 and a candidate site of the first type 5 is added to the end of the initial route, the new route is made 0 → 6 → 5 → 0. When the temporary delivery route is determined by returning to step 23 after step 26 or step 29 described later, the route satisfying the restriction condition in step 26 or step 29 is selected as the temporary delivery route.

In this embodiment, as shown in fig. 10(a), the initial route is 0 → 1 → 0, and the first type candidate stations 5, 7, 9 are added after the station 1 in the step 23 to form new routes 0 → 1 → 5 → 0, 0 → 1 → 7 → 0, 0 → 1 → 9 → 0, respectively (as shown in fig. 10 (b)). In fig. 10(b), the illustration of the yard 0 is omitted for simplicity of illustration, and the new routes 0 → 1 → 5 → 0, 0 → 1 → 7 → 0, 0 → 1 → 9 → 0 are illustrated as 1 → 5, 1 → 7, 1 → 9, respectively. The same applies to the following description.

It is then determined whether there is a station whose arrival time meets the time period limit among the first type of candidate stations (i.e., stations 5, 7, 9) (step 24).

If it is determined that there is a station whose arrival time matches the time zone limit among the first-class candidate stations, the first-class station matching the time zone limit and the yard constitute a new temporary route, and a new temporary route having the shortest travel time is selected (step 25). It is then determined whether the travel time of the new provisional route satisfies the restriction condition (here, 240 minutes), that is, whether the travel time of the new provisional route exceeds 240 minutes as the restriction condition (step 26). If it is determined in step 26 that the travel time of the route selected in step 25 satisfies the restriction condition (i.e., does not exceed 240 minutes), the process returns to step 23, and another first-type candidate station is added to the route having the shortest travel time selected in step 25. The limiting condition may be determined in accordance with actual circumstances, and is not limited to 240 minutes, and may be other time lengths. .

The arrival time of each first-type station and the time period limit for each first-type station in fig. 10(b) are set forth in table 4 below.

[ Table 4]

Site	9	5	7
				Time of arrival	10:10	9:00	9:40
Time period limitation	9:00-10:00	10:00-11:00	10:00-11:00

As shown in table 4 above, the time to arrive at station 9 at 8:30 (10:10) from station 1 is outside its limit time period (9:00-10:00), and the time to arrive at stations 5, 7 is outside the limit time period. It is determined in step 24 that there is no first-type station whose arrival time meets the time period limit among the first-type candidate stations.

If the determination result in step 24 is "no", the second type candidate stations (i.e., the second type stations not added to the delivery route) are added to the end of the temporary delivery route determined in step 23 to form a new route (step 27), as shown in fig. 10 c.

In this embodiment, adding a candidate station to the end of the route means: and adding the candidate station between the last station in the route and the yard.

In the present embodiment, since the route selected in step 22 is 0 → 1 → 0, the second type candidate sites 2, 3, 4, 6, 8, 10 are added after the site 1 in step 27, respectively, to constitute new routes 0 → 1 → 2 → 0, 0 → 1 → 3 → 0, 0 → 1 → 4 → 0, 0 → 1 → 6 → 0, 0 → 1 → 8 → 0, 0 → 1 → 10 → 0, respectively (as shown in fig. 10 (c)). In fig. 10(c), for the sake of simplicity of illustration, the illustration of the yard 0 is omitted, and the new routes 0 → 1 → 2 → 0, 0 → 1 → 3 → 0, 0 → 1 → 4 → 0, 0 → 1 → 6 → 0, 0 → 1 → 8 → 0, 0 → 1 → 10 → 0 are illustrated as 1 → 2, 1 → 3, 1 → 4, 1 → 6, 1 → 8, 1 → 10, respectively.

Then, the travel time of each new route formed in step 27 is calculated, and the route having the shortest travel time among the new routes is selected (step 28). Table 5 below schematically shows the travel time of each new route formed in step 27. Since the travel time (110 minutes) of the route 0 → 1 → 8 → 0 is shortest, the route selected in step 28 is 0 → 1 → 8 → 0 as shown in fig. 10 (d).

[ Table 5]

Further, after the route having the shortest travel time is selected in step 28, it is determined whether or not the travel time of the selected route satisfies the restriction condition (240 minutes) (step 29). When the restriction condition is satisfied, the process returns to step 23, and each of the first type candidate stations is added to the end of the route (0 → 1 → 8 → 0) having the shortest travel time selected in step 28, as shown in fig. 10 (e).

It is then determined in step 24 whether there is a station of the first category of candidate stations (i.e., stations 5, 7, 9) whose arrival time meets the time period limit. The arrival times and time period limits for each first type station are set forth in table 6 below.

[ Table 6]

As shown in table 6 above, there is a station 5 whose arrival time meets the time zone limit among the first type candidate stations (i.e., stations 5, 7, 9), and only one station (station 5) meets the limit condition, so as shown in fig. 10(f), the route 0 → 1 → 8 → 5 → 0 to which the station 5 is added is the route having the shortest travel time to be selected in step 25 (step 25). In addition, the following table 7 shows the travel time of the route 0 → 1 → 8 → 5 → 0.

[ Table 7]

Driving route	Travel time (minutes)
		0→1→8→5→0	220

Subsequently, the process proceeds to step 26, where it is determined whether or not the travel time of the route 0 → 1 → 8 → 5 → 0 selected in step 25 satisfies the restriction condition. As shown in table 7, since the travel time 220 minutes of the route 0 → 1 → 8 → 5 → 0 does not exceed 240 minutes, and the restriction condition is satisfied, the process returns to step 23 again, and each of the first type candidate stations (7, 9) is added to the end of the route (0 → 1 → 8 → 5 → 0) having the shortest travel time which has been selected most recently, as shown in fig. 10 (g). Table 8 below describes the arrival time of each first-type candidate station added to the end of the route 0 → 1 → 8 → 5 → 0 and the time period limit for each first-type station.

[ Table 8]

Site	9	7
			Time of arrival	11:50	11:10
Time period limitation	9:00-10:00	10:00-11:00

As shown in table 8, since the arrival times of the stations 7 and 9 are both outside the time limit period, it is determined in step 24 that there is no station whose arrival time meets the time limit in the first type candidate stations (stations 7 and 9). Then, the process proceeds to step 27, and as shown in fig. 10(h), the second type candidate stations (2, 3, 4, 6, 10) are added to the end of the route (0 → 1 → 8 → 5 → 0), respectively, to form a new route. Table 9 below describes the travel time corresponding to each new route.

[ Table 9]

Among the routes shown in table 9, the travel time of the route (0 → 1 → 8 → 5 → 10 → 0) is the shortest, so in step 28, as shown in fig. 10(i), the route (0 → 1 → 8 → 5 → 10 → 0) is selected as the route with the shortest time. Since the travel time of this route is 300 minutes, it is determined in step 29 that the travel time of this route exceeds 240 minutes, which is the limiting condition, and the limiting condition is not satisfied. Then, as shown in fig. 10(j), the route 0 → 1 → 8 → 5 → 10 → 0 and the preceding route 0 → 1 → 8 → 5 → 0 is selected as a complete distribution route (step 30). Then, returning to step 21, the generation of another complete delivery route is started. Table 10 below shows the arrival times of the respective stations and the time period limits for the respective first type stations in one complete delivery route generated at step 30.

[ Table 10]

In the route 0 → 1 → 8 → 5 → 0 shown in table 10, the arrival time (8:00) of the yard 0 shown by the black frame is substantially the departure time since the yard 0 is the departure point. The same applies to the following description.

Fig. 11 shows the complete route generated according to the flow shown in fig. 9. In the present embodiment 1, 3 complete routes, i.e., 0 → 1 → 8 → 5 → 0, 0 → 10 → 6 → 7 → 0, and 0 → 2 → 9 → 4 → 3 → 0, are generated in total in accordance with the flow shown in fig. 9. Tables 11 and 12 below show the arrival time of each station in the last 2 routes and the time period limit for each first-type station, respectively.

[ Table 11]

Site	0	10	6	7	0
						Time of arrival	8:00	8:30	9:20	11:40	12:00
Time period limitation	/	/	/	11:30-12:00	/

[ Table 12]

Site

0

2

9

4

3

0

Time of arrival

8:00

8:40

9:30

10:20

11:20

12:00

Time periodLimiting

/

/

9:00-10:00

/

/

/

According to the path planning method of the embodiment, the following beneficial technical effects can be obtained: the distribution route can be automatically planned, and the labor cost is saved; complex parameters do not need to be set, so that the use is convenient; because the waiting time of the vehicle is not required to be set, the vehicle does not need to be stopped midway, the invalid operation of the vehicle is reduced, and the distribution cost is reduced.

Example 2

In example 2, an initial route is generated using the savings value. The meaning of saving the value will be described below with reference to fig. 12(a) and 12 (b).

As shown in fig. 12(a), if the i site is distributed individually, the time taken is: t1+ t2, the time taken if delivered to j site alone is: t3+ t4, the time taken if i, j are distributed together is: t1+ t5+ t4, the savings are: t1+ t2+ t3+ t 4- (t1+ t5+ t4) ═ t2+ t 3-t 5.

As shown in fig. 12(b), taking sites 1 and 2 as an example, if site 1 is distributed alone, the time taken is: 60+ 70-130 minutes, if delivered to site 2 alone, the time taken is: 80+ 40-120 minutes, if delivered to stations 1, 2 together, takes: 60+90+40 is 190 minutes, the saving value is the total time of the station 1 and the station 2 which are separately distributed, and the total time of the stations 1 and 2 which are distributed together is 130+120 and 190 is 60 minutes.

According to the method shown in fig. 12(a) to (b), the time (i.e., the saved value) saved when any 2 stations are delivered together can be calculated as compared with when they are delivered individually.

Fig. 13 is a flowchart of generating an initial delivery route (hereinafter simply referred to as "initial route") in embodiment 2. The travel time required to reach each station from the yard and each station to each other is first acquired (step 31). Then, it is determined whether there is a first candidate pair of stations that satisfies the time period restriction when the distribution route is formed with the yard (step 32). If the determination result in step 32 is yes, the saving values for all such pairs of candidate stations of the first type when forming the distribution route with the yard are calculated (step 33). The delivery route with the greatest savings value is then selected as the initial route (step 34).

Fig. 14(a) to 14(d) are schematic views showing the first type of candidate station pairs satisfying the time zone restriction to form an initial route with the yard.

Fig. 14(a) illustrates yards 0 and 10 stations. As shown in table 13, 4 sites out of 10 (i.e., sites 1, 5, 7, 9) are the first type sites.

[ Table 13]

Site	1	9	5	7
					Time period limitation	8:00-9:00	9:00-10:00	10:00-11:00	11:30-12:00

It is assumed that only 2 pairs of candidate stations of the first type (stations 1, 5) and (stations 1, 9) satisfy the time period limit when forming a distribution route with the yard 0. Here, the arrival time of each station in the distribution route 0 → 1 → 5 → 0 composed of the stations 1, 5 and the yard 0, the time zone limit of the first type candidate station 1, 5, and the saving value of the route are described in the following table 14. The left side of fig. 14(b) shows the case and the required travel time when the stations 1 and 5 form the distribution route together with the yard 0, and the right side of fig. 14(b) shows the case and the required travel time when the stations 1 and 5 form the distribution route together with the yard 0.

[ Table 14]

The arrival time of each station in the distribution route 0 → 1 → 9 → 0 composed of the stations 1, 9 and the yard 0, the time zone limit of the first type candidate station 1, 9, and the saving value of the route are described in the following table 15. The left side of fig. 14(c) shows the case and the required travel time when the stations 1 and 9 form the distribution route together with the yard 0, and the right side of fig. 14(c) shows the case and the required travel time when the stations 1 and 9 form the distribution route together with the yard 0.

[ Table 15]

As shown in tables 14 and 15, since the saving value of the route 0 → 1 → 9 → 0 is the largest, the route 0 → 1 → 9 → 0 is selected as the initial route in step 34 as shown in fig. 14 (d).

If the determination result in step 32 is "no", a pair of stations consisting of one first-type candidate station and one second-type candidate station is selected, and all such pairs of stations are generated (step 35). Then, it is determined whether or not there is a station pair satisfying the time zone limit when the station pair generated in step 35 and the yard constitute the distribution route (step 36). If the determination result in step 36 is yes, the saving values for all such pairs of stations when forming the distribution route with the yard are calculated (step 37). The delivery route with the greatest savings value is then selected as the initial route (step 38).

Fig. 15(a) to 15(e) are schematic views showing that a station pair consisting of one first-type candidate station and one second-type candidate station satisfying the time zone restriction forms an initial route with the yard.

For ease of understanding of the explanation, it is assumed that it is determined in step 36 that there are 4 site pairs that meet the time period limit, i.e., (sites 1, 2), (sites 1, 3), (sites 2, 9), (sites 4, 9). In these 4 site pairs, sites 1, 9 are sites of a first type and sites 2, 3, 4 are sites of a second type.

The arrival time of each of the distribution routes 0 → 1 → 2 → 0 composed of the stations 1, 2 and the yard 0, the time zone limit of the first type station 1, and the saving value of the route are described in the following table 16. The left side of fig. 15(a) shows the case and the required travel time when the stations 1 and 2 form the distribution route together with the yard 0, and the right side of fig. 15(a) shows the case and the required travel time when the stations 1 and 2 form the distribution route together with the yard 0.

[ Table 16]

The arrival time of each station in the distribution route 0 → 1 → 3 → 0 composed of the stations 1, 3 and the yard 0, the time zone limit of the first type candidate station 1, and the saving value of the route are described in the following table 17. The left side of fig. 15(b) shows the case and the required travel time when the stations 1 and 3 form the distribution route together with the yard 0, and the right side of fig. 15(b) shows the case and the required travel time when the stations 1 and 3 form the distribution route together with the yard 0.

[ Table 17]

The arrival time of each of the distribution routes 0 → 2 → 9 → 0 composed of the stations 2, 9 and the yard 0, the time zone limit of the first type station 9, and the saving value of the route are described in the following table 18. The left side of fig. 15(c) shows the case and the required travel time when the stations 2 and 9 form the distribution route with the yard 0, respectively, and the right side of fig. 15(c) shows the case and the required travel time when the stations 2 and 9 form the distribution route together with the yard 0.

[ Table 18]

The arrival time of each of the distribution routes 0 → 4 → 9 → 0 composed of the stations 4, 9 and the yard 0, the time zone limit of the first type station 9, and the saving value of the route are described in the following table 19. The left side of fig. 15(d) shows the case and the required travel time when the stations 4 and 9 form the distribution route with the yard 0, respectively, and the right side of fig. 15(d) shows the case and the required travel time when the stations 4 and 9 form the distribution route together with the yard 0.

[ Table 19]

As shown in tables 16 to 19, since the saving value of the route 0 → 2 → 9 → 0 is 80 and the maximum, the route 0 → 2 → 9 → 0 is selected as the initial route in step 38 as shown in FIG. 15 (e).

If the determination result in step 36 is "no", any 2 second-type candidate station group node pairs are selected, and all such node pairs are generated (step 39). The savings for all such pairs of stations to form a distribution route with the yard, respectively, are then calculated (step 40). The delivery route with the greatest savings value is then selected as the initial route (step 41).

Fig. 16(a) to 16(c) show the travel time required for each of the 2 second-type candidate stops to form the distribution route together with the yard, and fig. 16(d) shows the initial route determined at step 41.

[ Table 20]

Site pair	2、3	2、4	2、6	……	i、j
						Saving value
	40	60	100	……	n

Table 20 records all the station pairs generated in step 39 and the savings when these station pairs respectively form a distribution route with yard 0. Wherein i, j represent the second type of candidate site pairs, n represents the savings value, the units of which are minutes.

Assuming that the maximum saving value in table 20 is 100 minutes and the corresponding station pair is (station 2, 6), the delivery route 0 → 2 → 6 → 0 of the station pair and yard 0 is selected as the initial route (as shown in fig. 16 (d)).

In order to generate a complete delivery route in addition to the initial route shown in fig. 14(d), fig. 15(e), or fig. 16(d), it is necessary to further add a candidate site to the initial route. Fig. 17(a) shows a case where a candidate site is added to the initial route shown in fig. 14(d), fig. 17(b) shows a case where a candidate site is added to the initial route shown in fig. 15(e), and fig. 17(c) shows a case where a candidate site is added to the initial route shown in fig. 16 (d). For convenience of explanation, it is assumed that the initial route shown in fig. 15(e) is 0 → 1 → 2 → 0.

In the initial route shown in fig. 14(d) and 15(e), there are one or 2 first-type sites that have time-segment restrictions. When adding a candidate site to such a route, in order to avoid the newly added site from affecting the first type site in the route, the newly added site is required to be positioned after the last first type site.

For example, in fig. 17(a), since both stations 1, 9 are first type stations, with a time period limitation, the newly joining station n needs to be located after station 9 (i.e., between station 9 and yard 0). In fig. 17(b), only station 1 is the first type station, and thus the newly joining station n may be located between station 1 and station 2, or between station 2 and yard 0. In fig. 17(c), stations 2, 6 are both type ii stations, with no time period limitation, so the newly joining station n may be located between stations 2, 6 or between the yard and stations 2, 6.

The method for generating a complete route will be described below with reference to fig. 18 to 21. FIG. 18 is a flow chart for generating a complete route. The steps in fig. 18 that are the same as those in fig. 9 are denoted by the same reference numerals, and detailed description thereof is omitted.

Assume that the initial route generated is 0 → 1 → 2 → 0, where site 1 is a first type of site and site 2 is a second type of site. The new delivery route is formed after the first type station 5, 7, 9 waiting to join the delivery route joins the last first type station 1 in the initial route 0 → 1 → 2 → 0, respectively (i.e., joins between the station 1 and the station 2, and between the station 2 and the yard 0, respectively) (step 43). As shown in table 21 and table 22 below, it is assumed that, in step 24, only 2 routes of 0 → 1 → 9 → 2 → 0, 0 → 1 → 2 → 5 → 0 satisfy the time limit period of the first type station in the route, and none of the other new delivery routes configured in step 43 satisfy the time limit period of the first type station.

[ Table 21]

[ Table 22]

Then, as shown in fig. 19(b), the route 0 → 1 → 9 → 2 → 0 having the shortest travel time is selected from the above 2 routes (step 25). Since the travel time of the route does not exceed 240 minutes (corresponding to step 26) which is the limiting condition, the process returns to step 43, and the addition of the first type station is continued after the last first type station 9 of the route 0 → 1 → 9 → 2 → 0 as shown in fig. 19 (c).

As shown in table 23 below, it is assumed that only 1 route 0 → 1 → 9 → 2 → 5 → 0 satisfies the time period restriction of the first type station in the route as judged in step 24. Then, as shown in fig. 19 d, the route is selected as the route having the shortest travel time in step 25, and it is judged in step 26 that the route satisfies the restriction condition (240 minutes) from table 23.

[ Table 23]

Since the travel time of the route shown in table 23 does not exceed 240 minutes (corresponding to step 26) as the restriction condition, the process returns to step 43 again, and continues to add the first type station 7 after the last first type station 5 of the route 0 → 1 → 9 → 2 → 5 → 0 as shown in fig. 19(e), forming a new route 0 → 1 → 9 → 2 → 5 → 7 → 0.

As shown in table 24 below, since the arrival time of the station 7 in the new route 0 → 1 → 9 → 2 → 5 → 7 → 0 is outside the restriction period, that is, the new route does not satisfy the period restriction of the first type station, it is judged in step 24 that there is no first type station satisfying the period restriction after joining the route 0 → 1 → 9 → 2 → 5 → 0.

[ Table 24]

Since the determination result in step 24 is "no", the process proceeds to step 47, and each of the second type candidate stations (3, 4, 6, 8, 10) is added after the last first type station 5 in the route 0 → 1 → 9 → 2 → 5 → 0 (between the station 5 and the yard 0 in the case of the present embodiment), as shown in fig. 20 (a). Then, as shown in table 25 below, the travel time of the new route formed by adding each of the second type candidate stations is calculated, and as shown in fig. 20(b), the new route having the shortest travel time is selected as 0 → 1 → 9 → 2 → 5 → 3 → 0 (step 28).

[ Table 25]

As shown in table 25, since the travel time of the route 0 → 1 → 9 → 2 → 5 → 3 → 0 is 220 minutes and 240 minutes as the restriction condition is not exceeded, it is judged at step 29 that the restriction condition is satisfied, and the step returns to step 43, and as shown in fig. 20(c), the first type station 7 is continuously added after the last first type station 5 of the route 0 → 1 → 9 → 2 → 5 → 3 → 0, to form the route 0 → 1 → 9 → 2 → 5 → 3 → 7 → 0, 0 → 1 → 9 → 2 → 7 → 3 → 0, respectively. The arrival times, time period limits, and travel times for these 2 routes are set forth in tables 26 and 27, respectively.

[ Table 26]

[ Table 27]

From the descriptions in tables 26 and 27, it is determined in step 24 that there is no first type station satisfying the time zone restriction of the first type station after the joining route 0 → 1 → 9 → 2 → 5 → 3 → 0. Then, the process proceeds to step 47, and as shown in fig. 20(d), the second type sites 4, 6, 8, 10 are added after the last first type site 5 of the route 0 → 1 → 9 → 2 → 5 → 3 → 0, respectively. The route formed and the travel time of the route are shown in table 28 below. In table 28, the left side "… …" indicates that a part of the route is omitted, and the right side "… …" indicates that the travel time of a part of the route is omitted.

[ Table 28]

Distribution route	Travel time (minutes)
		0→1→9→2→5→3→4→0	260
0→1→9→2→5→6→3→0	270
		0→1→9→2→5→3→6→0	280
0→1→9→2→5→3→8→0	290
		0→1→9→2→5→10→3→0	300
……	……

In step 28, the delivery route 0 → 1 → 9 → 2 → 5 → 3 → 4 → 0 having the shortest travel time in the table 28 is selected, and in step 29, it is judged that the travel time 260 minutes of the route exceeds 240 minutes which is the limiting condition, so that in step 30, as shown in fig. 20(e), the route 0 → 1 → 9 → 2 → 5 → 3 → 0 is determined as a complete delivery route. And then returns to step 21 for generation of a new distribution route.

Fig. 21 schematically shows the entire complete route generated according to the flow shown in fig. 18. In the present embodiment 2, 2 complete routes, i.e., 0 → 1 → 9 → 2 → 5 → 3 → 0 and 0 → 1 → 9 → 2 → 5 → 3 → 0, are generated in total in accordance with the flow shown in fig. 18.

According to the path planning method of the embodiment, the following beneficial technical effects can be obtained: the distribution route can be automatically planned, and the labor cost is saved; complex parameters do not need to be set, so that the use is convenient; because the waiting time of the vehicle is not required to be set, the vehicle does not need to be stopped midway, the invalid operation of the vehicle is reduced, and the distribution cost is reduced.

Example 3

In embodiment 3, the method for generating the initial route is the method for generating the initial route in embodiment 1, and the method for generating the complete delivery route is the method for generating the complete delivery route in embodiment 2. For the sake of brevity of this specification, the description of the generation method of the initial route and the complete delivery route of embodiment 3 is omitted.

In addition, the method of generating the distribution route of embodiment 3 may be: the initial route generation method in embodiment 2 is adopted as the initial route generation method, and the complete delivery route generation method in embodiment 1 is adopted as the complete delivery route generation method.

According to example 3, the same technical effects as those of examples 1 and 2 can be obtained.

Fig. 22 is a flow chart of path planning for the remaining (i.e., non-joined delivery routes) first type candidate sites after the complete delivery route has been generated. Assume that there are candidate sites 5, 7 of the first type remaining after the complete delivery route is generated, wherein the time period limit for site 5 is 10:00-11:00 and the time period limit for site 7 is 11:30-12: 00.

First, it is determined whether there is a first type candidate site (step 51). If the determination result is yes, the first candidate station with the earliest arrival time is selected to form the initial route with the yard (step 52). Fig. 23(a) shows a case where one first type candidate stop 5 and the yard 0 form the distribution route 0 → 5 → 0, and fig. 23(b) shows a case where one first type candidate stop 7 and the yard 0 form the distribution route 0 → 7 → 0. The time for the vehicle to depart from yard 0 is then calculated based on the service time of the first type candidate station and the travel time required from the yard to that station (step 53).

Table 29 and table 30 below show the departure time (arrival time) of the vehicle from the yard 0, the arrival time at the station and the yard, and the time zone restrictions of the first type candidate station in the route 0 → 5 → 0, the route 0 → 7 → 0, respectively.

[ Table 29]

Parking lot/station	0	5	0
				Time of arrival	9:00	10:00	10:40
Time period limitation	/	10:00-11:00	/

[ Table 30]

Parking lot/station	0	7	0
				Time of arrival	10:10	11:30	12:20
Time period limitation	/	11:30-12:00	/

As shown in table 29, the time at which the station 5 requires the delivery vehicle to arrive (i.e., service) is 10:00 at the earliest, and therefore, in step 52, route 0 → 5 → 0 is selected as the initial route. Further, as shown in fig. 23(a), since the travel time from the yard 0 to the station 5 is 60 minutes, the vehicle needs to start from the yard 0 at 9:00 in order to arrive at the station 5 at 10: 00. However, it is not required that the delivery vehicle arrive at the earliest time, but within the time limit of the station 5. For example, the delivery vehicle may only need to arrive at station 5 within 10:00-11:00, in which case the vehicle may need to depart from yard 0 during 9:00-10: 00.

After the route 0 → 5 → 0 is selected as the initial route in step 52 and the time for the vehicle to depart from the yard 0 is calculated in step 53, it is determined whether or not there is any first type candidate station (step 54). If there is a first type candidate site (here, site 7), the temporary delivery route is determined, and each first type candidate site is added to the end of the temporary delivery route to generate a new temporary route (step 55). When the temporary delivery route is determined in step 55, the initial route generated in step 52 is initially selected as the temporary delivery route, and when the process returns to step 54 after step 58 and then reaches step 55, the route satisfying the limitation condition in step 58 is selected as the temporary delivery route. After step 55, it is determined whether or not there is a station whose arrival time meets the time zone limit among the first type candidate stations joined to the temporary delivery route (step 56).

In the present embodiment, since there is only one first type candidate station 7 other than the route 0 → 5 → 0, a new provisional route 0 → 5 → 7 → 0 is generated in step 55, and it is determined whether the arrival time of the station 7 in the new provisional route matches the time period limit in step 56.

Fig. 24 is a schematic diagram showing the new provisional route 0 → 5 → 7 → 0 generated in step 55. The following table 31 represents the arrival times of the respective stations in the new provisional route 0 → 5 → 7 → 0 generated at step 55 and the time period restrictions for the respective first type stations 5, 7.

[ Table 31]

Site	0	5	7	0
					Time of arrival	9:00	10:00	10:40	11:30
Time period limitation	/	10:00-11:00	11:30-12:00

If it is determined that there is a station whose arrival time meets the time zone limit among the first-class candidate stations, the first-class stations meeting the time zone limit and the yard are combined into a new temporary route, and the new temporary route having the shortest travel time is selected (step 57). It is then determined whether the travel time of the new temporary route satisfies the restriction condition (here, 240 minutes), that is, whether the travel time of the new temporary route exceeds 240 minutes as the restriction condition (step 58). In the case where it is judged in step 58 that the travel time of the route selected in step 57 satisfies the restriction condition (i.e., does not exceed 240 minutes), the process returns to step 54.

As can be seen from table 31, the arrival time of the first type candidate station 7 does not meet the time zone limit, and the determination result in step 58 is that there is no first type station whose arrival time meets the time zone limit, and the process proceeds to step 59, and in step 59, the temporary delivery route (here, 0 → 5 → 0) determined in step 55 is taken as a complete delivery route. Then, the process returns to step 51, and generation of a new complete delivery route is started until the first type candidate station does not remain as a result of the determination in step 51, and route planning for the remaining first type candidate station is ended.

In the flowchart of fig. 22, step 53 may be performed after moving step 53 to another step (e.g., step 59) instead of performing step 52 and step 54. For example, when the process proceeds after step 53 is shifted to step 59, after the complete delivery route is generated, the time when the vehicle departs from the yard 0 is calculated from the service time of the first type candidate station in the delivery route and the travel time required from the yard to the station.

In the present specification, the travel time between the yard and each station and between the stations are merely examples, and may be appropriately changed to facilitate understanding of the route planning method of the present invention.

According to the path planning method of the invention, the following beneficial technical effects can be obtained: the distribution route can be automatically planned, and the labor cost is saved; complex parameters do not need to be set, so that the use is convenient; the method can meet the distribution requirements of all client sites with time section limitation, ensure the normal operation of the client sites and improve the credit of distribution companies; because the waiting time of the vehicle is not required to be set, the vehicle does not need to be stopped midway, the invalid operation of the vehicle is reduced, and the distribution cost is reduced.

Claims (18)

1. A path planning method for planning a delivery route of vehicles in a path including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the path planning method comprising:

a first route generation step of forming a first temporary distribution route by each of the first type stations, which are to be added to the distribution route, and the yard, selecting the first temporary distribution route, which satisfies a time period limitation of the first type stations and has the shortest travel time, as the first route, and forming a second temporary distribution route by each of the second type stations, which is to be added to the distribution route, and the yard, when there is no first temporary distribution route satisfying the time period limitation of the first type stations, and selecting the second temporary distribution route, which has the shortest travel time, as the first route.

2. The path planning method according to claim 1, comprising:

a second route generation step of adding each first-type station, which is waiting to be added to at least one first-type station in the distribution routes, to the end of the first route or forming a third temporary distribution route based on the end of the temporary distribution route generated by the first route, and selecting the third temporary distribution route which meets the time period limit of the first-type station and has the shortest driving time as a second route, and if a third temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the tail end of the first route or the tail end of a temporary distribution route generated based on the first route to form a fourth temporary distribution route, and selecting the fourth temporary distribution route with the shortest driving time as the second route.

3. The path planning method according to claim 1, comprising:

a second route generation step of adding each first-type station of at least one first-type station waiting to be added to the distribution routes to a third temporary distribution route after a last first-type station of the first routes or a last first-type station of temporary distribution routes generated based on the first routes, selecting the third temporary distribution route satisfying a time period limit of the first-type station and having a shortest travel time as a second route, and in the case that there is no third temporary distribution route satisfying the time period limit of the first-type station, adding each second-type station of at least one second-type station waiting to be added to the distribution routes to a last first-type station of the first routes or a fourth temporary distribution route after a last first-type station of the temporary distribution routes generated based on the first routes And selecting the fourth temporary distribution route with the shortest travel time as the second route.

4. A path planning method for planning a delivery route of vehicles in a path including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the path planning method comprising:

a first route generation step of configuring, with the yard, each of at least one site pair of 2 sites of the first type among the distribution routes as a first temporary distribution route, selecting, as a first route, the first temporary distribution route that satisfies a time period limit for the first type of sites and has a maximum saving value, configuring, with the yard, each of at least one site pair of 1 site of the first type and 1 site of the second type among the distribution routes as a second temporary distribution route in the case where there is no first temporary distribution route that satisfies a time period limit for the first type of sites, selecting, as the first route, the second temporary distribution route that satisfies a time period limit for the first type of sites and has a maximum saving value, and selecting, in the case where there is no second temporary distribution route that satisfies a time period limit for the first type of sites, forming a third temporary distribution route by each of the station pairs consisting of 2 stations of the second type waiting to join the distribution routes and the yard respectively, selecting the third temporary distribution route with the largest economic value as the first route,

wherein the savings value is a difference between a total time required to separately deliver the 2 stations of the pair and a total time required to deliver the 2 stations of the pair together.

5. The path planning method according to claim 4, comprising:

a second route generation step of adding each first-type station of at least one first-type station waiting to be added to the distribution route to the end of the first route or forming a fourth temporary distribution route based on the end of the temporary distribution route generated by the first route, and selecting the fourth temporary distribution route which meets the time period limit of the first-type station and has the shortest driving time as a second route, and in the case that a fourth temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fifth temporary distribution route, and selecting the fifth temporary distribution route with the shortest driving time as the second route.

6. The path planning method according to claim 4, comprising:

a second route generation step of adding each first-type station of at least one first-type station waiting to be added to the distribution routes to a fourth temporary distribution route after a last first-type station of the first routes or a temporary distribution route generated based on the first routes, selecting the fourth temporary distribution route satisfying a time period limit of the first-type station and having a shortest travel time as a second route, and in the case where there is no fourth temporary distribution route satisfying the time period limit of the first-type station, adding each second-type station of at least one second-type station waiting to be added to the distribution routes to a last first-type station of the first routes or forming a fifth temporary distribution route after a last first-type station of the temporary distribution routes generated based on the first routes And selecting the fifth temporary distribution route with the shortest travel time as the second route.

7. A path planning method according to any one of claims 1 to 6, comprising:

a travel time acquisition step of acquiring, before the first route generation step, travel times between the yard and each of the stations and between the plurality of stations, the travel times being used for calculating the travel time of the distribution route.

8. The path planning method according to any one of claims 2, 3, 5 and 6, comprising:

and a third route generation step of selecting one or more first-class stations to form a third route with the yard on the premise of meeting the time period limit of the first-class stations only when the first-class stations waiting to join the distribution route exist after the second route generation step.

9. A path planning method according to any one of claims 2, 3, 5 and 6, characterized in that:

the travel time of the first route and the second route is less than a preset travel time limit value.

10. The path planning method according to claim 8, characterized in that:

and the running time of the third route is less than a preset running time limit value.

11. A route planning apparatus that plans a delivery route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning apparatus characterized by comprising:

and a first route generation module configured to form a first temporary distribution route by each of the first type stations waiting to join the distribution route and the yard, select the first temporary distribution route satisfying a time period limitation of the first type stations and having a shortest travel time as a first route, form a second temporary distribution route by each of the second type stations waiting to join the distribution route and the yard if there is no first temporary distribution route satisfying the time period limitation of the first type stations, and select the second temporary distribution route having a shortest travel time as the first route.

12. The path planner according to claim 11, comprising:

a second route generation module, configured to join each of the first type stops waiting to join the distribution routes to an end of the first route or to form a third temporary distribution route based on an end of a temporary distribution route generated by the first route, and select the third temporary distribution route that satisfies a time period limit of the first type stops and has a shortest travel time as a second route, and if a third temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution routes to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fourth temporary distribution route, and selecting the fourth temporary distribution route with the shortest driving time as the second route.

13. The path planner according to claim 11, comprising:

a second route generation module, configured to join each of the first type sites waiting to join the distribution routes to a third temporary distribution route after a last first type site in the first routes or a last first type site in temporary distribution routes generated based on the first routes, select the third temporary distribution route satisfying a time period limit of the first type sites and having a shortest travel time as a second route, and join each of the second type sites waiting to join the distribution routes to a fourth temporary distribution route after a last first type site in the first routes or after a last first type site in temporary distribution routes generated based on the first routes in a case where there is no third temporary distribution route satisfying the time period limit of the first type sites And selecting the fourth temporary distribution route with the shortest travel time as the second route.

14. A route planning apparatus that plans a delivery route of vehicles in a route including a yard and a plurality of stations including a first type station having a limitation on a service period and a second type station having no limitation on the service period, the route planning apparatus characterized by comprising:

a first route generation module that configures each of at least one site pair of 2 sites of a first type to be added to the distribution routes as a first temporary distribution route with the yard, selects the first temporary distribution route that satisfies a time zone limitation of the first type and has a maximum saving value as a first route, configures each of at least one site pair of 1 site of the first type and 1 site of the second type to be added to the distribution routes as a second temporary distribution route with the yard when there is no first temporary distribution route that satisfies a time zone limitation of the first type, selects the second temporary distribution route that satisfies a time zone limitation of the first type and has a maximum saving value as a first route, and if there is no second temporary distribution route that satisfies a time zone limitation of the first type, forming a third temporary distribution route by each of the station pairs consisting of 2 stations of the second type waiting to join the distribution routes and the yard respectively, selecting the third temporary distribution route with the largest economic value as the first route,

wherein the savings value is a difference between a total time required to separately deliver the 2 stations of the pair and a total time required to deliver the 2 stations of the pair together.

15. The path planner according to claim 14, comprising:

a second route generation module, configured to join each of the first type stops waiting to join the distribution routes to an end of the first route or to form a fourth temporary distribution route based on an end of a temporary distribution route generated by the first route, and select the fourth temporary distribution route that satisfies a time period limit of the first type stops and has a shortest travel time as a second route, and in the case that a fourth temporary distribution route which meets the time period limit of the first type of stops does not exist, adding each second type of stop in at least one second type of stop waiting to be added into the distribution route to the end of the first route or the end of a temporary distribution route generated based on the first route to form a fifth temporary distribution route, and selecting the fifth temporary distribution route with the shortest driving time as the second route.

16. The path planner according to claim 14, comprising:

a second route generation module, configured to join each of the first type sites waiting to join the distribution routes after a last first type site in the first routes or to form a fourth temporary distribution route after a last first type site in temporary distribution routes generated based on the first routes, select, as a second route, the fourth temporary distribution route that satisfies a time period limitation of the first type sites and has a shortest travel time, and in a case where there is no fourth temporary distribution route that satisfies the time period limitation of the first type sites, join each of the second type sites waiting to join the distribution routes after a last first type site in the first routes or form a fifth temporary distribution route after a last first type site in temporary distribution routes generated based on the first routes And selecting the fifth temporary distribution route with the shortest travel time as the second route.

17. A path planner according to any of the claims 11-16, comprising:

and a travel time acquisition module that acquires travel times between the yard and each of the stations and between the plurality of stations before the first route generation module generates the first route, the travel times being used to calculate the travel time of the distribution route.

18. A path planner according to any of the claims 12, 13, 15, 16, comprising:

and a third route generation module, configured to select one or more first type stations to form a third route with the yard on the premise that a time period limit of the first type stations is met, in a case where there is only the first type stations waiting to join the distribution route after the second route generation module generates the second route.

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