Travel plan generation device and travel plan generation program

Abstract

To provide a travel plan generation device and a travel plan generation program capable of generating a travel plan to secure travel performance even on a rough road.SOLUTION: A travel plan generation device comprises a processor. The processor acquires road surface information to a destination of a vehicle and generates a travel plan, on the basis of the road surface information, including acceleration and a speed of the vehicle on a route to the destination within a range where the vehicle can maintain a slip ratio indicating that wheels of the vehicles are brought into contact with the ground.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a driving plan generation device and a driving plan generation program. [Background technology]

[0002] Patent Document 1 discloses a vehicle control device that calculates tire generated force (road μ×ground contact load) based on road μ, and generates a driving plan under conditions that do not exceed the tire generated force. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-063106 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in Patent Document 1 generates a driving plan to prevent the vehicle from slipping, but there was a need for technology that can ensure off-road capability (driving that shortens arrival times) even on rough roads, for example.

[0005] The present disclosure has been made in consideration of the above, and aims to provide a driving plan generation device and a driving plan generation program that can generate a driving plan that ensures off-road capability even on rough roads. [Means for solving the problem]

[0006] The driving plan generation device according to the present disclosure includes a processor, which acquires road surface information to a vehicle's destination, and generates a driving plan based on the road surface information, the driving plan including the acceleration and vehicle speed of the vehicle on the route to the destination, within a range of slip ratios that cause the wheels of the vehicle to contact the road surface.

[0007] The driving plan generation program of the present disclosure causes a processor to acquire road surface information to a vehicle's destination, and generate a driving plan including the acceleration and vehicle speed of the vehicle on the route to the destination based on the road surface information, within a range of slip ratios that cause the wheels of the vehicle to contact the road surface. Effect of the Invention

[0008] According to the present disclosure, it is possible to generate a driving plan that ensures drivability even on rough roads. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing a configuration of a driving schedule generating system including a driving schedule generating device according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of an acceleration map used when the driving schedule generating device according to the embodiment generates a driving schedule. [Diagram 3] FIG. 3 is a diagram showing an example of an acceleration map used when the driving schedule generating device according to the embodiment generates a driving schedule. [Figure 4] FIG. 4 is a diagram showing an example of a vehicle speed map used when the driving schedule generating device according to the embodiment generates a driving schedule. [Diagram 5] FIG. 5 is a flowchart showing an example of a processing procedure of a first example of a driving schedule generating method executed by the driving schedule generating device according to the embodiment. [Figure 6] FIG. 6 is a diagram for explaining a method for selecting the fastest slip ratio and the efficiency-optimizing slip ratio in a first example of the driving schedule generating method executed by the driving schedule generating device according to this embodiment. [Figure 7] FIG. 7 is a diagram for explaining a method of selecting an efficiency-optimizing slip ratio in a first example of the drive schedule generating method executed by the drive schedule generating device according to this embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of a processing procedure of a second example of a driving schedule generating method executed by the driving schedule generating device according to the embodiment. [Figure 9] FIG. 9 is a diagram for explaining a method of selecting a time-optimal slip ratio and an efficiency-optimal slip ratio in a second example of the driving schedule generating method executed by the driving schedule generating device according to this embodiment. [Figure 10] FIG. 10 is a diagram for explaining a method of selecting a time-optimal slip ratio and an efficiency-optimal slip ratio in a second example of the driving schedule generation method executed by the driving schedule generation device according to this embodiment. [Figure 11] FIG. 11 is a flowchart showing an example of a processing procedure of a third example of a driving schedule generating method executed by the driving schedule generating device according to this embodiment. [Figure 12] FIG. 12 is a diagram for explaining a method of limiting the slip ratio in a third example of the driving schedule generating method executed by the driving schedule generating device according to the embodiment. [Figure 13] FIG. 13 is a flowchart showing an example of a processing procedure of a fourth example of a driving schedule generating method executed by the driving schedule generating device according to this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A driving schedule generating device and a driving schedule generating program according to an embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that are easily replaceable by a person skilled in the art, or those that are substantially the same.

[0011] (Drive plan generation system) A driving schedule generation system including a driving schedule generation device according to an embodiment will be described with reference to Fig. 1. As shown in Fig. 1, the driving schedule generation system includes a driving schedule generation device 1 and a data center 2. The driving schedule generation device 1 and the data center 2 have a communication function and are configured to be able to communicate with each other through a network N. This network N is configured, for example, from an Internet network, a mobile phone network, or the like.

[0012] (Drive plan generation device) The driving plan generating device 1 is for generating a driving plan for a vehicle based on road surface information up to the vehicle's destination. Here, the "driving plan" refers to a plurality of parameters including the acceleration, vehicle speed, etc. of the vehicle on the route to the destination. When generating this driving plan, the driving plan generating device 1 may, for example, divide a predetermined section of the road to the destination into blocks, and generate a plurality of parameters including the vehicle speed and acceleration for each block.

[0013] The driving schedule generating device 1 is mounted on a moving body such as a vehicle. Examples of the vehicle include an engine vehicle, a hybrid vehicle (HEV: Hybrid Electric Vehicle), a plug-in hybrid electric vehicle (PHEV: Plug-in Hybrid Electric Vehicle), a fuel cell electric vehicle (FCEV: Fuel Cell Electric Vehicle), and an electric vehicle (BEV: Battery Electric Vehicle). The vehicle on which the driving schedule generating device 1 is mounted may be a manually driven vehicle or an automatically driven vehicle.

[0014] In addition to being mounted on a moving object such as a vehicle, the driving schedule generating device 1 may be operated by mounting some of its functions (for example, functions of the control unit 10, etc.) on a server device or the like capable of communicating with the vehicle. In this way, by mounting some of the functions of the driving schedule generating device 1 on a server device or the like, the calculation load on the vehicle side can be reduced.

[0015] As shown in FIG. 1, the driving schedule generating device 1 includes a control unit 10, a communication unit 20, a storage unit 30, and a sensor group 40.

[0016] Specifically, the control unit 10 includes a processor such as a CPU (Central Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field-Programmable Gate Array), a GPU (Graphics Processing Unit), etc., and a memory (main storage unit) such as a RAM (Random Access Memory), a ROM (Read Only Memory), etc.

[0017] The control unit 10 executes various programs to comprehensively control the operation of various components mounted on the driving schedule generation device 1. Specifically, the control unit 10 functions as an information acquisition unit 11, a driving schedule generation unit 12, and a required energy calculation unit 13 through the execution of various programs.

[0018] The information acquisition unit 11 collects and acquires various information required to generate a driving plan. Examples of the information acquired by the information acquisition unit 11 include driving route information, road surface information, and available energy information.

[0019] The travel route information is information about a route along which the vehicle is scheduled to travel (hereinafter, referred to as a "planned travel route"). This travel route information includes, for example, coordinates of the current location and the destination, the distance to the destination, roads to be taken to the destination, an expected arrival time to the destination, and information about a target arrival time to the destination set by the driver, for example. The information acquisition unit 11 acquires the travel route information based on, for example, information set in a navigation system of the vehicle.

[0020] The road surface information is information about the road surface of the planned travel route of the vehicle. This road surface information includes information about the shape, gradient, running resistance, road surface condition (dry road surface, wet road surface, etc.), slip rate of the road surface, etc. The information acquisition unit 11 acquires the road surface information by using vehicle-to-vehicle communication with other vehicles (for example, a preceding vehicle traveling ahead), road-to-vehicle communication with roadside devices installed on the road, communication with the data center 2, and the sensor group 40 of the vehicle itself. The information acquisition unit 11 may acquire the road surface information only once at a predetermined timing, or may acquire the road surface information when the road surface condition changes, or at regular intervals.

[0021] The available energy information is information about energy that can be used by the vehicle. For example, if the vehicle is an engine vehicle (conveyor vehicle), the available energy information may include the amount of fuel. If the vehicle is an electric vehicle equipped with a motor and a battery, the available energy information may include the battery capacity (SOC: State Of Charge).

[0022] The driving plan generating unit 12 generates a driving plan for the vehicle based on the information acquired by the information acquiring unit 11. Specifically, the driving plan generating unit 12 generates the driving plan by selecting an acceleration map and a vehicle speed map.

[0023] Fig. 2 is an example of an acceleration map used by the trip plan generating unit 12 when the vehicle is an electric vehicle, with the vertical axis indicating average acceleration and the horizontal axis indicating fuel (SOC). Fig. 3 is an example of an acceleration map used by the trip plan generating unit 12 when the vehicle is an engine vehicle, with the vertical axis indicating average acceleration and the horizontal axis indicating fuel consumption (energy). The trip plan generating unit 12 selects an acceleration map by selecting one operation line from a plurality of operation lines (characteristic lines) set in advance, for example, as shown in Fig. 2.

[0024] 4 is an example of a vehicle speed map used by the trip plan generating unit 12, with the vertical axis indicating vehicle speed and the horizontal axis indicating road surface gradient. The trip plan generating unit 12 selects a vehicle speed map by selecting one operating line from a plurality of pre-set operating lines (characteristic lines), for example, as shown in the figure. Note that in the vehicle speed map shown in the figure, the upper operating line is the operating line selected as a base, and the worse the road surface, the lower the operating line selected.

[0025] The driving plan generating unit 12 first selects a base acceleration map and a vehicle speed map, and reselects the acceleration map and the vehicle speed map as necessary based on the slip ratio of the road surface. Note that the specific procedure for generating the driving plan performed by the driving plan generating unit 12 will be described later (see Figs. 5 to 13).

[0026] The required energy calculation unit 13 calculates the required energy when the vehicle travels along the planned travel route, based on the travel plan generated by the travel plan generation unit 12. When the acceleration map and the vehicle speed map are reselected based on the slip rate of the road surface (when the travel plan is corrected), the required energy calculation unit 13 recalculates the required energy based on the corrected travel plan.

[0027] The communication unit 20 is composed of, for example, a DCM (Data Communication Module) and performs communication with other vehicles, roadside devices, the data center 2, and the like by wireless communication via the network NW.

[0028] The storage unit 30 is composed of recording media such as an EPROM (Erasable Programmable ROM), a hard disk drive (HDD), and removable media. Examples of removable media include a universal serial bus (USB) memory, a compact disc (CD), a digital versatile disc (DVD), and a Blu-ray (registered trademark) disc (BD). The storage unit 30 can store an operating system (OS), various programs, various tables, various databases, and the like.

[0029] The memory unit 30 stores, as necessary, for example, driving route information acquired by the information acquisition unit 11, road surface information, available energy information, sensor data detected by the sensor group 40, an acceleration map (see Figures 2 and 3), a vehicle speed map (see Figure 4), a map describing the relationship between the soil characteristics of the road surface and the slip ratio, and the like.

[0030] The sensor group 40 is made up of a plurality of sensors for detecting road surface information. The sensor group 40 includes, for example, a laser sensor, a 3D-LiDAR, a millimeter wave sensor, an infrared sensor, a camera, a GPS sensor, an acceleration sensor, a vehicle speed sensor, and the like, which are attached to the front of the vehicle.

[0031] The sensor group 40 detects information regarding the shape of the road surface, such as unevenness, using a laser sensor, a 3D-LiDAR, a millimeter wave sensor, an infrared sensor, a camera, and the like included in the sensor group 40. The sensor group 40 also detects information regarding the position of the vehicle using a GPS sensor included in the sensor group 40. The sensor group 40 then transmits the detected sensor data to the control unit 10 and the storage unit 30 as necessary.

[0032] (Data Center) The data center 2 is configured, for example, by a server device, and collects and stores road surface information in advance. Then, in response to a request from the driving schedule generating device 1, the data center 2 transmits the road surface information of the road on which the vehicle is traveling to the driving schedule generating device 1.

[0033] (Driving plan generation method: First embodiment) An example of a processing procedure of a first embodiment of a driving schedule generating method executed by the driving schedule generating device 1 will be described with reference to Fig. 5 to Fig. 7. Note that some or all of the processes shown in Fig. 5 may be performed before the vehicle starts traveling, or may be performed while the vehicle is traveling.

[0034] 5, the information acquisition unit 11 acquires driving route information based on information set in a vehicle navigation system (step S1). Next, the information acquisition unit 11 acquires road surface information of the planned driving route by using, for example, vehicle-to-vehicle communication, road-to-vehicle communication, communication with the data center 2, the sensor group 40, etc. (step S2).

[0035] Next, the information acquisition unit 11 acquires available energy information of the vehicle (step S3). Next, the driving plan generation unit 12 calculates a target travel time to the destination (step S4). In step S4, the target travel time is calculated based on, for example, an expected arrival time or a target arrival time included in the driving route information.

[0036] Next, the driving plan generating unit 12 selects a base acceleration map and a vehicle speed map (step S5). In step S5, a base driving plan is generated by selecting a base operation line (characteristic line) in the acceleration map and the vehicle speed map illustrated in Fig. 2 to Fig. 4, for example. Next, the required energy calculating unit 13 calculates the required energy based on the driving plan generated in step S5 (step S6).

[0037] Next, the driving plan generating unit 12 determines whether or not there is a bad road on the planned driving route based on the road surface information acquired in step S2 (step S7). If it is determined in step S7 that there is no bad road on the planned driving route (No in step S7), the driving plan generating unit 12 maintains the base acceleration map and vehicle speed map (step S8) and completes this process.

[0038] On the other hand, in step S7, if it is determined that there is a bad road on the planned travel route (Yes in step S7), the travel plan generating unit 12 determines whether or not to prioritize off-road performance (step S9). In the determination in step S9, for example, a message such as "Do you want to prioritize off-road performance?" is displayed on the screen (display) of the navigation system of the vehicle. Then, for example, if the driver selects (input on the screen) to accept, a positive determination is made, and if the driver selects not to accept, a negative determination is made.

[0039] If it is determined in step S9 that the traveling performance is important (Yes in step S9), the travel schedule generating unit 12 selects the fastest slip ratio among the slip ratios when traveling the planned travel route (step S10). This "fastest slip ratio" refers to the slip ratio that, among the slip ratios set for the vehicle, provides the shortest arrival time at the destination.

[0040] 6 is a graph showing the relationship between the arrival time and the slip ratio, where the vertical axis is the arrival time at the destination and the horizontal axis is the slip ratio. As shown in the figure, in step S10, within the selectable range of slip ratios set according to the target travel time, the slip ratio that provides the shortest arrival time at the destination is selected as the fastest slip ratio.

[0041] Next, the travel plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the fastest slip ratio selected in step S10 (step S11). In step S11, the travel plan is corrected by reselecting the operation line (characteristic line) based on the fastest slip ratio in the acceleration map and the vehicle speed map shown in Figs. 2 to 4, for example.

[0042] Next, the required energy calculation unit 13 recalculates the required energy based on the driving plan corrected in step S11 (step S12), and then the process is completed.

[0043] Here, if it is determined in step S9 that off-road performance is not important (No in step S9), the driving plan generating unit 12 selects an efficient optimum slip ratio from among the slip ratios when driving the planned driving route (step S13). This "efficient optimum slip ratio" refers to the slip ratio that provides the highest efficiency to the destination among the slip ratios set for the vehicle. Note that "efficiency" in this case refers to fuel efficiency if the host vehicle is an engine vehicle (conventional vehicle), and electricity efficiency if the host vehicle is an electric vehicle.

[0044] 7 is a graph showing the relationship between efficiency (fuel economy, electricity economy) and slip ratio, with the vertical axis representing efficiency and the horizontal axis representing slip ratio. As shown in the figure, in step S13, within the selectable range of slip ratios set according to the target travel time, the slip ratio that provides the highest efficiency is selected as the efficiency-optimized slip ratio.

[0045] Next, the travel plan generating unit 12 reselects the acceleration map and vehicle speed map corresponding to the efficient optimal slip ratio selected in step S13 (step S14), and proceeds to step S12. In step S14, the travel plan is corrected by reselecting an operating line (characteristic line) based on the efficient optimal slip ratio in the acceleration map and vehicle speed map exemplified in, for example, Figures 2 to 4.

[0046] In this way, in a first example of the driving schedule generation method according to the embodiment, road surface information up to the vehicle's destination is acquired, and the fastest slip ratio or the most efficient slip ratio is selected based on the road surface information. Then, a driving schedule is generated that includes the vehicle's acceleration and speed on the route to the destination within the range where the fastest slip ratio or the most efficient slip ratio is obtained. Therefore, according to the driving schedule generation method according to the embodiment, it is possible to selectively generate a driving schedule that prioritizes arrival time or efficiency.

[0047] (Driving plan generation method: second embodiment) An example of a processing procedure of the second embodiment of the driving schedule generating method executed by the driving schedule generating device 1 will be described with reference to Fig. 8 to Fig. 10. Note that some or all of the processes shown in Fig. 8 may be performed before the vehicle starts traveling, or may be performed while the vehicle is traveling.

[0048] 8, the information acquisition unit 11 acquires driving route information based on information set in a vehicle navigation system (step S21). Next, the information acquisition unit 11 acquires road surface information of the planned driving route by using, for example, vehicle-to-vehicle communication, road-to-vehicle communication, communication with the data center 2, the sensor group 40, etc. (step S22).

[0049] Next, the information acquisition unit 11 acquires available energy information of the vehicle (step S23). Next, the driving plan generation unit 12 calculates a target travel time to the destination (step S24). In step S24, the target travel time is calculated based on, for example, an expected arrival time or a target arrival time included in the driving route information.

[0050] Next, the driving plan generating unit 12 selects a base acceleration map and a vehicle speed map (step S25). In step S25, a base driving plan is generated by selecting a base operation line (characteristic line) in the acceleration map and the vehicle speed map illustrated in Fig. 2 to Fig. 4, for example. Next, the required energy calculating unit 13 calculates the required energy based on the driving plan generated in step S25 (step S26).

[0051] Next, the driving plan generating unit 12 determines whether or not there is a bad road on the planned driving route based on the road surface information acquired in step S22 (step S27). If it is determined in step S27 that there is no bad road on the planned driving route (No in step S27), the driving plan generating unit 12 maintains the base acceleration map and vehicle speed map (step S28) and completes this process.

[0052] On the other hand, if it is determined in step S27 that there is a bad road on the planned travel route (Yes in step S27), the travel plan generating unit 12 determines whether or not to prioritize the travel performance (step S29). In the determination in step S29, for example, a message such as "Do you want to prioritize the travel performance?" is displayed on the screen (display) of the navigation system of the vehicle. Then, for example, if the driver selects to accept (input on the screen), a positive determination is made, and if the driver selects not to accept, a negative determination is made.

[0053] If it is determined in step S29 that the traveling performance is important (Yes in step S29), the travel schedule generating unit 12 selects a time-optimal slip ratio from among the slip ratios when traveling the planned travel route (step S30). This "time-optimal slip ratio" refers to a slip ratio that, among the slip ratios set for the vehicle, provides the shortest arrival time at the destination and the highest efficiency to the destination.

[0054] FIG. 9 is a graph showing the relationship between arrival time and slip ratio, with the vertical axis showing the arrival time at the destination and the horizontal axis showing the slip ratio. FIG. 10 is a graph showing the relationship between efficiency (fuel consumption, electricity consumption) and slip ratio, with the vertical axis showing the efficiency and the horizontal axis showing the slip ratio. As shown in FIG. 9, in step S30, attention is paid to a 3σ section of slip ratios that provides the shortest arrival time at the destination within a selectable range of slip ratios set according to the target travel time. Then, as shown in FIG. 10, the slip ratio that provides the highest efficiency in this 3σ section is selected as the time-optimal slip ratio.

[0055] Next, the travel plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the time-optimum slip ratio selected in step S30 (step S31). In step S31, the travel plan is corrected by reselecting the operation line (characteristic line) based on the time-optimum slip ratio in the acceleration map and the vehicle speed map exemplified in, for example, Figs. 2 to 4.

[0056] Next, the required energy calculation unit 13 recalculates the required energy based on the driving plan corrected in step S31 (step S32), and then ends this process.

[0057] If it is determined in step S29 that the traveling performance is not important (No in step S29), the travel schedule generating unit 12 selects an efficient optimum slip ratio from among the slip ratios when traveling the planned travel route (step S33). This "efficient optimum slip ratio" refers to the slip ratio that provides the highest efficiency to the destination from among the slip ratios set for the vehicle, as shown in FIG. 10.

[0058] Next, the travel plan generating unit 12 reselects the acceleration map and vehicle speed map corresponding to the efficient optimal slip ratio selected in step S33 (step S34), and proceeds to step S32. In step S34, the travel plan is corrected by reselecting an operating line (characteristic line) based on the efficient optimal slip ratio in the acceleration map and vehicle speed map exemplified in Figures 2 to 4, for example.

[0059] In this way, in the second example of the driving schedule generation method according to the embodiment, road surface information up to the vehicle's destination is acquired, and a time-optimal slip ratio or an efficiency-optimal slip ratio is selected based on the road surface information. Then, a driving schedule is generated that includes the vehicle's acceleration and vehicle speed on the route to the destination within the range that provides the time-optimal slip ratio or the efficiency-optimal slip ratio. Therefore, according to the driving schedule generation method according to the embodiment, it is possible to selectively generate a driving schedule that emphasizes arrival time efficiency or efficiency.

[0060] (Driving plan generation method: third embodiment) An example of a processing procedure of the third embodiment of the driving schedule generating method executed by the driving schedule generating device 1 will be described with reference to Fig. 11 and Fig. 12. Note that some or all of the processes shown in Fig. 11 may be performed before the vehicle starts traveling, or may be performed while the vehicle is traveling.

[0061] 11, the information acquisition unit 11 acquires driving route information based on information set in a vehicle navigation system (step S41). Next, the information acquisition unit 11 acquires road surface information of the planned driving route by using, for example, vehicle-to-vehicle communication, road-to-vehicle communication, communication with the data center 2, the sensor group 40, etc. (step S42).

[0062] Next, the information acquisition unit 11 acquires available energy information of the vehicle (step S43). Next, the driving plan generation unit 12 calculates a target travel time to the destination (step S44). In step S44, the target travel time is calculated based on, for example, an expected arrival time or a target arrival time included in the driving route information.

[0063] Next, the driving plan generating unit 12 selects a base acceleration map and a vehicle speed map (step S45). In step S45, a base driving plan is generated by selecting a base operation line (characteristic line) in the acceleration map and the vehicle speed map illustrated in Fig. 2 to Fig. 4, for example. Next, the required energy calculating unit 13 calculates the required energy based on the driving plan generated in step S45 (step S46).

[0064] Next, the driving plan generating unit 12 determines whether or not there is a bad road on the planned driving route based on the road surface information acquired in step S42 (step S47). If it is determined in step S47 that there is no bad road on the planned driving route (No in step S47), the driving plan generating unit 12 maintains the base acceleration map and vehicle speed map (step S48) and completes this process.

[0065] On the other hand, when it is determined in step S47 that a bad road exists on the planned travel route (Yes in step S47), the travel schedule generating unit 12 selects an optimum slip ratio (step S49). As the optimum slip ratio, for example, the efficiency optimum slip ratio (see FIG. 7) and the time optimum slip ratio (see FIG. 10) described above can be mentioned.

[0066] Next, the trip plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the optimal slip ratio selected in step S49 (step S50). Next, the trip plan generating unit 12 predicts the roll moment acting on the vehicle (step S51). In step S51, the roll moment is predicted based on, for example, the road surface shape, gradient, vehicle acceleration, vehicle speed, and slip ratio of each wheel contained in the road surface information. In addition to roll, moments such as yaw and pitch may also be predicted in step S51.

[0067] Next, the driving schedule generating unit 12 judges whether the roll moment predicted in step S51 is larger than a preset threshold value (step S52). The threshold value used in step S52 can be calculated experimentally in advance, for example, based on road surface information and a limit value of the slip ratio at which the wheels of the vehicle touch the road surface. Here, "contact with the road" in this embodiment refers to a state in which the attitude of the vehicle does not change significantly during a predetermined time, and the wheels do not continue to float, that is, the wheels do not continue to spin.

[0068] In step S52, if it is determined that the roll moment is greater than the threshold value (No in step S52), the travel schedule generator 12 maintains the acceleration map and the vehicle speed map selected in step S50 (step S53), and proceeds to step S56.

[0069] Here, when it is determined in step S52 that the roll moment is greater than the threshold value (Yes in step S52), the travel schedule generator 12 limits the slip ratio set for the vehicle to a predetermined slip ratio (step S54).

[0070] The upper diagram in Fig. 12 is a graph showing the relationship between the predicted value of roll moment and the slip ratio, with the vertical axis representing the predicted value of roll moment and the horizontal axis representing the slip ratio. The lower diagram in Fig. 12 is a graph showing the relationship between the arrival time at the destination and the slip ratio, with the vertical axis representing the arrival time at the destination and the horizontal axis representing the slip ratio. This diagram also shows an example in which a time-optimal slip ratio is selected in step S49. As shown in Fig. 12, in step S54, the selectable range of slip ratios is limited to a range that results in a slip ratio that causes the wheels of the vehicle to contact the road surface.

[0071] In addition, the "slip ratio at which the wheels come into contact with the road surface" may be, in addition to the slip ratio at which the wheels do not spin for a predetermined period of time as described above, a slip ratio at which multiple wheels do not spin at the same time, for example.

[0072] Next, the travel plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the slip ratio limited in step S54 (step S55). In step S55, the travel plan is corrected by reselecting the operation line (characteristic line) based on the slip ratio limited in step S54 in the acceleration map and the vehicle speed map exemplified in, for example, Figs. 2 to 4.

[0073] Next, the required energy calculation unit 13 recalculates the required energy based on the driving plan corrected in step S55 (step S56), and then ends this process.

[0074] In this way, in the third example of the driving plan generation method according to the embodiment, road surface information up to the vehicle's destination is acquired, and an optimal slip ratio (efficiency-optimal slip ratio, time-optimal slip ratio) is selected based on the road surface information. Then, a driving plan is generated that includes the vehicle's acceleration and vehicle speed on the route to the destination within a range that provides the optimal slip ratio and a range of slip ratios that allow the vehicle's wheels to contact the road surface. Therefore, according to the driving plan generation method according to the embodiment, a driving plan that ensures drivability even on rough roads can be generated. In addition, it is possible to reduce the time to arrive at the destination while preventing the vehicle's wheels from lifting off the ground during driving.

[0075] (Driving plan generation method: fourth embodiment) An example of the processing procedure of the fourth embodiment of the driving schedule generating method executed by the driving schedule generating device 1 will be described with reference to Fig. 13. Note that some or all of the processing of steps S61 to S70 shown in Fig. 13 may be performed before the vehicle starts traveling, or may be performed while the vehicle is traveling. Also, the processing of step S71 and subsequent steps shown in the figure is performed while the vehicle is traveling.

[0076] 13, the information acquisition unit 11 acquires driving route information based on information set in a vehicle navigation system (step S61). Next, the information acquisition unit 11 acquires road surface information of the planned driving route by using, for example, vehicle-to-vehicle communication, road-to-vehicle communication, communication with the data center 2, the sensor group 40, etc. (step S62).

[0077] Next, the information acquisition unit 11 acquires available energy information of the vehicle (step S63). Next, the driving plan generation unit 12 calculates a target travel time to the destination (step S64). In step S64, the target travel time is calculated based on, for example, an expected arrival time or a target arrival time included in the driving route information.

[0078] Next, the driving plan generating unit 12 selects a base acceleration map and a vehicle speed map (step S65). In step S65, a base driving plan is generated by selecting a base operation line (characteristic line) in the acceleration map and the vehicle speed map illustrated in Fig. 2 to Fig. 4, for example. Next, the required energy calculating unit 13 calculates the required energy based on the driving plan generated in step S65 (step S66).

[0079] Next, the driving plan generating unit 12 determines whether or not there is a bad road on the planned driving route based on the road surface information acquired in step S62 (step S67). If it is determined in step S67 that there is no bad road on the planned driving route (No in step S67), the driving plan generating unit 12 maintains the base acceleration map and vehicle speed map (step S68) and completes this process.

[0080] On the other hand, if it is determined in step S67 that a bad road exists on the planned travel route (Yes in step S67), the travel schedule generating unit 12 selects an optimum slip ratio (step S69). As the optimum slip ratio, for example, the efficiency optimum slip ratio (see FIG. 7) and the time optimum slip ratio (see FIG. 10) described above can be mentioned.

[0081] Next, the driving plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the optimal slip ratio selected in step S69 (step S70). Next, the driving plan generating unit 12 detects the soil characteristics of the road surface of the planned driving route (step S71). In step S71, the soil characteristics of the road surface are detected based on, for example, the running resistance included in the road surface information of the planned driving route.

[0082] Next, the driving schedule generating unit 12 calculates the slip ratio of the road surface of the planned driving route (step S72). In step S72, for example, the relationship between the soil characteristics of the road surface and the slip ratio is stored in advance in a map or the like, and the slip ratio is calculated by referring to the map using the soil characteristics detected in step S71.

[0083] Next, the driving schedule generating unit 12 judges whether or not it is necessary to reselect the maps (acceleration map, vehicle speed map) (step S73). In the judgment of step S73, for example, if the difference between the optimum slip ratio selected in step S69 and the slip ratio calculated in step S72 exceeds a preset value, a positive judgment is made, and if it is within the preset value, a negative judgment is made.

[0084] In step S73, if it is determined that reselection of the map is not necessary (No in step S73), the driving plan generator 12 maintains the acceleration map and the vehicle speed map selected in step S70 (step S74), and proceeds to step S76.

[0085] On the other hand, if it is determined in step S73 that reselection of the map is necessary (Yes in step S73), the travel plan generating unit 12 reselects the acceleration map and the vehicle speed map corresponding to the slip ratio calculated in step S72 (step S75). In step S75, the travel plan is corrected by reselecting the operation line (characteristic line) based on the slip ratio calculated in step S72 in the acceleration map and the vehicle speed map exemplified in, for example, Figures 2 to 4.

[0086] Next, the required energy calculation unit 13 recalculates the required energy based on the travel plan corrected in step S75 (or step S70) (step S76), and then ends this process.

[0087] In this way, in the fourth example of the driving plan generating method according to the embodiment, the deviation between the road surface information (slip ratio) acquired from the preceding vehicle, the data center 2, etc. and the road surface information (slip ratio) calculated from the soil properties of the road surface is fed back, and the driving plan is corrected based on the deviation. Therefore, according to the driving plan generating method according to the embodiment, even if the soil properties change and the slip ratio of the road surface changes, the driving plan can be corrected accordingly.

[0088] Further advantages and modifications may readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof.

[0089] For example, the driving schedule generation device 1 according to the embodiment can also function as a vehicle control device that controls a vehicle based on the generated driving schedule. In this case, the vehicle control device generates a driving schedule by any of the methods of the first to fourth embodiments. If the vehicle on which the driving schedule generation device 1 is installed is an autonomous vehicle, the driving schedule generation device 1 controls the acceleration and vehicle speed of the vehicle on the planned driving route based on the generated driving plan. If the vehicle on which the driving schedule generation device 1 is installed is a manually driven vehicle, the driving schedule generation device 1 presents the acceleration and vehicle speed of the vehicle on the planned driving route as indicator information of the vehicle.

[0090] Furthermore, the driving schedule generation device 1 according to the embodiment can be applied not only to vehicles that run on the ground, but also to moving bodies (e.g., space probes) used outside the Earth (in a space environment). In a space environment, road surface information is virtually nonexistent, so road surface information from a preceding moving body, a base station, or the vehicle itself is traveling is extremely useful. For this reason, for example, by analyzing road surface information while traveling on a road surface covered with regolith (regolith road surface) and calculating the slip ratio of the road surface, a driving schedule can be generated that ensures drivability even in a space environment. [Explanation of symbols]

[0091] 1. Driving plan generation device 10 Control section 11 Information acquisition department 12 Driving plan generation unit 13. Required energy calculation section 20 Communications Department 30 Storage section 40 Sensors N Network 2. Data Center

Claims

1. A processor is provided. The processor, Obtain road surface information to the vehicle's destination, generating a travel plan including an acceleration and a vehicle speed of the vehicle on a route to the destination within a range of a slip ratio at which the wheels of the vehicle contact the road surface based on the road surface information; selecting a fastest slip ratio that provides the fastest arrival time to the destination, an efficiency-optimum slip ratio that provides the highest efficiency to the destination, and a time-optimum slip ratio that provides the fastest arrival time to the destination and the highest efficiency to the destination based on the road surface information; generating the travel plan within a range in which the fastest slip ratio, the efficient slip ratio, or the time optimal slip ratio is achieved and in which the wheels of the vehicle are in contact with the road surface; Driving plan generation device.

2. The processor, Detecting soil characteristics of a road surface based on an acceleration of the vehicle while traveling; Calculating a slip ratio of a road surface based on the soil characteristics; correcting the driving plan based on the calculated slip ratio; The driving schedule generating device according to claim 1 .

3. The processor: Obtain road surface information to the vehicle's destination, generating a travel plan including an acceleration and a vehicle speed of the vehicle on a route to the destination within a range of a slip ratio at which the wheels of the vehicle contact the road surface based on the road surface information; selecting a fastest slip ratio that provides the fastest arrival time to the destination, an efficiency-optimum slip ratio that provides the highest efficiency to the destination, and a time-optimum slip ratio that provides the fastest arrival time to the destination and the highest efficiency to the destination based on the road surface information; generating the travel plan within a range in which the fastest slip ratio, the efficient slip ratio, or the time optimal slip ratio is achieved and in which the wheels of the vehicle are in contact with the road surface; A driving plan generation program that executes the above.

4. The processor, Detecting soil characteristics of a road surface based on an acceleration of the vehicle while traveling; Calculating a slip ratio of a road surface based on the soil characteristics; correcting the driving plan based on the calculated slip ratio; 4. The driving schedule generating program according to claim 3, which causes the following to be executed.

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