Road surface condition identification system, vehicle, program, and road surface condition identification method
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-14
- Publication Date
- 2026-08-13
Smart Images
Figure JP2026000945_13082026_PF_FP_ABST
Abstract
Description
Road surface condition identification system, vehicle, program, and road surface condition identification method
[0001] The present invention relates to a road surface condition identification system, a vehicle, a program, and a road surface condition identification method.
[0002] Patent Document 1 describes determining road conditions based on the pressure of the suspension of a work vehicle. [Prior art document] [Patent document] [Patent Document 1] U.S. Patent Application Publication No. 2004 / 122580
[0003] When a vehicle travels on a road surface in a bad condition, the vehicle may be damaged. Therefore, it is desired to accurately identify the condition of the road surface.
[0004] In one embodiment, a road surface condition identification system including at least one processor is provided. The at least one processor acquires tire behavior information indicating the behavior of tires provided in a vehicle and tire condition information indicating the condition of the tires, and based on the tire behavior information and the tire condition information, identifies the condition of the road surface on which the vehicle has traveled, and outputs road surface condition information indicating the condition of the road surface.
[0005] Note that the above summary of the invention does not list all the features of the present invention. Sub - combinations of these feature groups can also be inventions.
[0006] Shows the configuration of the vehicle management system 100. Shows the configuration of the vehicle 102. Shows the configuration of the management device 108. Shows an example of a road surface report. Shows an example of the processing flow of the control device 260. Shows an example of the computer 1200.
[0007] The following embodiments do not limit the invention according to the claims. Not all combinations of the features described in the embodiments are essential for the solution means of the invention.
[0008] Various embodiments may be described with reference to flowcharts or configuration diagrams. Each block in a flowchart or functional configuration diagram may represent (1) a stage in a process in which an operation is performed, or (2) a section of equipment that has the role of performing the operation. Certain stages and sections may be implemented by dedicated circuits, programmable circuits supplied with computer-readable instructions stored on a computer-readable medium, and / or processors supplied with computer-readable instructions stored on a computer-readable medium. Dedicated circuits may include digital and / or analog hardware circuits, and may include integrated circuits (ICs) and / or discrete circuits. Programmable circuits may include reconfigurable hardware circuits, including logic AND, logic OR, logic XOR, logic NAND, logic NOR, and other logic operations, flip-flops, registers, field-programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and other memory elements.
[0009] Computer-readable media may include any tangible device capable of storing instructions to be executed by a suitable device, and as a result, computer-readable media having instructions stored therein will comprise a product that includes instructions that can be executed to create means for performing operations specified in a flowchart or diagram. Examples of computer-readable media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, etc. More specific examples of computer-readable media may include floppy disks (registered trademark), diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), electrically erasable programmable read-only memory (EEPROM), static random access memory (SRAM), compact disk read-only memory (CD-ROM), digital multipurpose disc (DVD), Blu-ray (registered trademark) disc, memory stick, integrated circuit card, etc.
[0010] Computer-readable instructions may include assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages such as Smalltalk®, Java®, C++, and conventional procedural programming languages such as the C programming language or similar programming languages.
[0011] Computer-readable instructions may be provided locally or via a wide area network (WAN) such as a local area network (LAN) or the internet to the processor or programmable circuit of a programmable data processing device such as a computer. The computer may execute computer-readable instructions to create means for performing operations specified in a flowchart or configuration diagram. Here, the computer may be a PC (personal computer), tablet computer, smartphone, workstation, server computer, general-purpose computer, or special-purpose computer, and may also be a computer system in which multiple computers are connected. Such a computer system in which multiple computers are connected is also called a distributed computing system and is a computer in a broad sense. In a distributed computing system, multiple computers execute a part of the program, and as needed, data during program execution is passed between computers, so that multiple computers execute the program collectively.
[0012] Examples of processors include computer processors, central processing units (CPUs), processing units, microprocessors, digital signal processors, controllers, and microcontrollers. A computer may have one or more processors. In a multiprocessor system with multiple processors, each processor executes a portion of the program, and the processors collectively execute the program by passing program execution data between them as needed. For example, in the execution of multitasks, each of the multiple processors may execute a portion of each task in small chunks by switching tasks at each time slice. In this case, which part of a program each processor executes changes dynamically. Which part of a program each of the multiple processors executes may also be statically determined by multiprocessor-aware programming.
[0013] Figure 1 shows the configuration of a vehicle management system 100 according to one embodiment. The vehicle management system 100 comprises a vehicle 102, a communication network 106, a management device 108, a data server 110, and another vehicle 112. The vehicle 102, the management device 108, the data server 110, and the vehicle 112 are connected via the communication network 106. The vehicle management system 100 is an example of a road surface condition identification system. Each of the vehicle 102, the management device 108, and the vehicle 112, or any combination thereof, may be an example of a road surface condition identification system. Vehicles 102 and 112 are work vehicles equipped with front wheels and rear wheels. Vehicles 102 and 112 operate and perform work, for example, at a work site such as a mine. Vehicles 102 and 112 are work vehicles such as dump trucks, wheel loaders, or motor graders. Vehicles 102 and 112 may operate at the same work site, such as the same mine or the same construction site. Vehicles 102 and 112 may have the same configuration or functions. Vehicles 102 and 112 may be either manned or unmanned. A manned vehicle is a vehicle operated by a passenger. An unmanned vehicle is a vehicle that operates without the need for a passenger to operate it, even in the absence of a passenger.
[0014] The management device 108 may be located in a different location from the work site where vehicles 102 and 112 are working. In this case, the management device 108 communicates with vehicles 102 and 112 via a communication network 106 such as the Internet. The management device 108 may be located at the work site where vehicles 102 and 112 are working. In this case, the management device 108 communicates with vehicles 102 and 112 via a communication network 106 such as a local network (LAN). The management device 108 may also communicate with vehicles 102 and 112 using short-range wireless communication such as Bluetooth®. The work site may include a loading area or a soil disposal area.
[0015] Vehicle 102 collects tire behavior information indicating the behavior of the tires, tire condition information indicating the state of the tires, usage condition information indicating the state of the tires being used, and vehicle condition information indicating the state of vehicle 102. The vehicle condition information includes the position of vehicle 102. Based on the various information, vehicle 102 identifies the state of the road surface 104 at each location on the road surface 104 that vehicle 102 has traveled. Vehicle 102 transmits road surface condition information indicating the state of the road surface 104 at each location to the management device 108 or data server 110 via the communication network 106.
[0016] The management device 108 acquires road surface condition information of the road surface 104 from one or more vehicles, including vehicle 102 or vehicle 112, or from the data server 110 via the communication network 106. The road surface condition information is a numerical value specified according to the condition of the road surface, for example, a numerical value on a scale of 0 to 5, with a higher numerical value indicating a greater degree of unevenness in the road surface. Based on the road surface condition information of the road surface 104 collected by one or more vehicles, the management device 108 calculates a road surface score for a predetermined geographical area including the road surface 104. The road surface score is, for example, a numerical value on a scale of 0 to 5, with a higher numerical value indicating a greater degree of unevenness in the road surface. The road surface score may be expressed as a binary classification of Y and N. If the degree of unevenness in the road surface is less than a predetermined value, Y may be assigned, indicating that the road surface does not require maintenance, and if the degree of unevenness in the road surface is greater than a predetermined value, N may be assigned, indicating that the road surface requires maintenance.
[0017] A predetermined geographical area may be, for example, a grid-like area, or a rectangular area of 50 meters on each side. A predetermined geographical area may be any shape and size, such as the area of a work site like a loading area or soil removal area, the area of a road between work sites, the area between intersections of roads, the area of a road between work sites and intersections, or the overall area including multiple work sites and the roads connecting each work site.
[0018] The management device 108 generates a road surface report based on the road surface score of the road surface 104. The road surface report visually represents the condition of the road surface. The road surface report includes, for example, an image in which the road surface score is described for each area or location of the road surface on a map, a list of road surface scores for each area or location of the road surface, an image in which the necessity of road surface maintenance is described as Y or N for each area or location of the road surface on a map, or a heat map in which the road surface score is represented by color for each area or location of the road surface on a map. The management device 108 displays the road surface report to the user of the management device 108.
[0019] The management device 108 may transmit a road surface report to vehicle 102 or vehicle 112 via the communication network 106. The control device of vehicle 102 or vehicle 112 may display the road surface report to the operator of vehicle 102 or vehicle 112. The management device 108 may transmit a road surface report to the data server 110 via the communication network 106. The data server 110 stores the road surface report transmitted from the management device 108. The data server 110 provides the road surface report in response to requests from the management device 108, vehicle 102, or vehicle 112. The road surface score and road surface report are examples of road surface condition information.
[0020] The data server 110 may store road surface condition information transmitted from the vehicle 102. The data server 110 may provide road surface condition information in response to a request from the management device 108. The management device 108 may calculate a road surface score and generate a road surface report based on the road surface condition information provided by the data server 110.
[0021] Vehicle 102 may transmit various information it has collected to the management device 108. The management device 108 may acquire various information collected by one or more vehicles, including vehicle 102 or vehicle 112, or from the data server 110. Based on the various information, the management device 108 may identify the condition of the road surface 104 at each location on the road surface 104 that vehicle 102 has traveled. Based on the road surface condition information indicating the condition of the road surface 104 at each location on the road surface 104, the management device 108 may calculate a road surface score and generate a road surface report.
[0022] The condition of the road surface 104 is determined by considering information indicating tire behavior, tire condition, tire usage, and vehicle 102 condition, thus accurately determining the condition of the road surface 104. The user of the management device 108 can grasp the condition of the road surface at the work site of vehicle 102 with high accuracy, enabling efficient maintenance of the road surface at the work site. By having vehicle 102 or vehicle 112 drive on roads with good road conditions, damage to the tires and vehicle frame caused by driving on rough roads can be reduced. Therefore, the vehicle management system 100 can achieve low-cost operation (LCO).
[0023] Figure 2 shows the configuration of a vehicle 102 according to this embodiment. The vehicle 102 includes a plurality of tires 202, a plurality of fluid pressure suspensions 204, a frame 206, a measuring device 210, a detection device 220, a usage status acquisition device 230, a vehicle status acquisition device 240, a control device 260, a communication device 280, and an output device 290. The control device 260 is an example of a road surface condition identification system.
[0024] A fluid-pressure suspension 204 is connected to some or all of the multiple tires 202. The fluid-pressure suspension 204 is connected to the frame 206, which is the skeleton of the vehicle 102.
[0025] The measuring device 210 measures the behavior of the tire 202. The measuring device 210 acquires tire behavior information indicating the behavior of the tire 202 and outputs it to the control device 260. The tire behavior information includes information indicating the acceleration of the tire 202, information indicating the pressure of the fluid pressure suspension 204, or information indicating the strain of the frame 206. The tire behavior information may be time-series data indicating the behavior of the tire 202. The tire behavior information may indicate the behavior of multiple tires 202 on the vehicle 102. The information indicating the acceleration of the tire 202 may indicate the acceleration in the vertical direction. The pressure of the fluid pressure suspension 204 fluctuates as the tire 202 moves relative to the frame 206. Therefore, fluctuations in the pressure of the fluid pressure suspension 204 indicate the behavior of the tire 202. The strain of the frame 206 fluctuates as the movement of multiple tires 202 is transmitted to the frame 206 via the fluid pressure suspension 204. Therefore, fluctuations in the strain of the frame 206 reflect the behavior of the tire 202.
[0026] The measuring device 210 has at least one acceleration sensor 212, at least one pressure sensor 214, and at least one strain sensor 216. The tire-side measuring device 210 may have at least one of the acceleration sensor 212, pressure sensor 214, and strain sensor 216, or any combination thereof. The acceleration sensor 212 is attached to the tire 202 and measures the acceleration of the tire 202. The pressure sensor 214 measures the pressure of the fluid pressure suspension 204. The strain sensor 216 is attached to the frame 206 and measures the strain of the frame 206.
[0027] The detection device 220 is mounted on at least one tire 202 and detects the state of the tire 202. The detection device 220 may be mounted inside the tire 202. The detection device 220 may be installed on all of the multiple tires 202. The detection device 220 acquires tire state information indicating the state of the tire 202 and outputs it to the control device 260. The state of the tire 202 is at least one of the temperature or pressure of the tire 202. The detection device 220 may also acquire tire state information indicating the internal state of the tire 202 and output it to the control device 260. The internal state of the tire 202 is at least one of the internal temperature and pressure of the tire 202. The tire state information includes information indicating the pressure of the tire 202 and information indicating the temperature of the tire 202. The tire state information may be time-series data indicating the state of the tire 202.
[0028] The detection device 220 includes at least one of a temperature sensor 222 and a pressure sensor 224. The temperature sensor 222 measures the temperature of the tire 202. The pressure sensor 224 measures the pressure of the tire 202.
[0029] The usage status acquisition device 230 acquires the usage status of the tire 202. The usage status acquisition device 230 acquires tire usage information indicating the usage status of the tire 202 and outputs it to the control device 260. The tire usage information includes information indicating the usage period of the tire 202, information indicating the outside temperature of the tire 202, and information indicating the mileage of the tire 202.
[0030] The usage status acquisition device 230 includes a temperature sensor 232, an odometer 234, and a timer 236. The temperature sensor 232 measures the ambient temperature of the tire 202. The odometer 234 measures the distance traveled by the tire 202. The timer 236 measures the usage period of the tire 202.
[0031] The vehicle status acquisition device 240 acquires the status of the vehicle 102. The vehicle status acquisition device 240 acquires vehicle status information indicating the status of the vehicle 102 and outputs it to the control device 260. The vehicle status information includes information indicating the speed of the vehicle 102, information indicating the acceleration of the vehicle 102, information indicating the angular velocity of the vehicle 102, information indicating the steering angle of the vehicle 102, position information indicating the position of the vehicle 102, and information indicating the time. The vehicle status information may be time-series data indicating the status of the vehicle 102. The vehicle status information may include information indicating the load amount of cargo loaded on the vehicle 102. The load amount may be calculated from the change in pressure of the fluid pressure suspension 204 when the cargo is loaded.
[0032] The vehicle status acquisition device 240 includes a speed sensor 242, an acceleration sensor 244, an angular velocity sensor 246, a steering angle sensor 248, a position sensor 250, and a clock 252. The speed sensor 242 measures the speed of the vehicle 102. The acceleration sensor 244 measures the acceleration of the vehicle 102. The angular velocity sensor 246 measures the angular velocity of the vehicle 102. The steering angle sensor 248 measures the steering angle of the vehicle 102. The position sensor 250 measures the position of the vehicle 102. The clock 252 measures the time.
[0033] The control device 260 includes an information acquisition unit 262, an information storage unit 264, a road surface condition identification unit 266, a communication control unit 268, and an output control unit 270. The information acquisition unit 262 acquires tire behavior information, tire condition information, tire usage information, and vehicle condition information. The information storage unit 264 stores the various information acquired by the information acquisition unit 262 in association with it. The information storage unit 264 may store tire information indicating the size of the tire 202, the type or model number of the tire 202, or the material of the rubber material of the tire 202. The information storage unit 264 may store the tire information of the tire 202 when the control device 260 is attached to the vehicle 102, or it may store the tire information of the tire 202 when the control device 260 is manufactured. The information storage unit 264 may acquire and store the tire information of the tire 202 stored in the data server 110 via the communication control unit 268.
[0034] The road surface condition identification unit 266 identifies the condition of the road surface 104 that the vehicle 102 has traveled on, based on tire behavior information and tire condition information, and outputs road surface condition information indicating the condition of the road surface 104. The road surface condition is, for example, the flatness of the road surface, or the degree of undulation or unevenness of the road surface.
[0035] The road surface condition identification unit 266 identifies the condition of the road surface 104 on which the vehicle 102 has traveled, based on the pressure of the fluid pressure suspension 204 measured by the pressure sensor 214. When the vehicle 102 travels on a road surface 104 with a high degree of unevenness, vertical acceleration occurs in the tires 202. Since the fluid pressure suspension 204 is subjected to vertical inertial force, the pressure of the fluid pressure suspension 204 fluctuates. The greater the degree of unevenness of the road surface 104, the greater the amount of pressure fluctuation. Therefore, the road surface condition identification unit 266 may identify a greater degree of unevenness in the road surface 104 the larger the value of an index indicating the variation in multiple pressures measured over a predetermined period. An index indicating the variation in pressure is, for example, variance, standard deviation, or coefficient of variation.
[0036] The road surface condition identification unit 266 may identify the condition of the road surface 104 on which the vehicle 102 has traveled, based on the strain of the frame 206 measured by the strain sensor 216. When the vehicle 102 travels on a road surface 104 with a high degree of unevenness, vertical acceleration occurs in the tires 202. Since the frame 206 receives vertical inertial force at the connection point with the fluid pressure suspension 204, the strain of the frame 206 increases. The greater the degree of unevenness of the road surface 104, the greater the strain of the frame. Therefore, the road surface condition identification unit 266 may identify a higher degree of unevenness on the road surface 104 as the strain value increases.
[0037] The road surface condition identification unit 266 may identify the condition of the road surface 104 on which the vehicle 102 has traveled, based on the acceleration of the tires 202 measured by the acceleration sensor 212. When the vehicle 102 travels on a road surface 104 with a high degree of unevenness, vertical acceleration occurs in the tires 202. The greater the degree of unevenness of the road surface 104, the greater the vertical acceleration of the tires 202. Therefore, the road surface condition identification unit 266 may identify a greater degree of unevenness in the road surface 104 as the value of an index indicating the variation of multiple accelerations measured over a predetermined period is larger. An index indicating the variation of acceleration may be, for example, variance, standard deviation, or coefficient of variation.
[0038] The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the temperature of the tire 202 measured by the temperature sensor 222. The higher the temperature of the tire 202, the higher the temperature of the tread portion of the tire 202, and the softer the rubber material of the tread portion becomes. As a result, the tread portion absorbs shocks better, and the amount of pressure fluctuation of the fluid pressure suspension 204 becomes smaller. Therefore, the road surface condition identification unit 266 may identify the condition of the road surface 104 such that the degree of unevenness of the identified road surface 104 becomes greater the higher the temperature of the tire 202. For example, when the values of the indices showing the variation of multiple pressures of the fluid pressure suspension 204 are the same when the temperature of the tire 202 is lower and when it is higher, the road surface condition identification unit 266 identifies the degree of unevenness as 2 when the temperature of the tire 202 is lower and as 3 when the temperature of the tire 202 is higher. In this way, by using the temperature of the tire 202 as a basis, the road surface condition identification unit 266 can identify the road surface condition with a more accurate numerical value.
[0039] The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the pressure of the tire 202 measured by the pressure sensor 224. The higher the pressure of the tire 202, the harder the tire 202 becomes. As a result, the fluid pressure suspension 204 receives a greater impact, and the amount of pressure fluctuation in the fluid pressure suspension 204 becomes larger. Therefore, the road surface condition identification unit 266 may identify the condition of the road surface 104 such that the degree of unevenness of the identified road surface 104 becomes smaller as the pressure of the tire 202 increases. For example, when the values of the indices showing the variation in multiple pressures of the fluid pressure suspension 204 are the same when the pressure of the tire 202 is lower and when it is higher, the road surface condition identification unit 266 identifies the degree of unevenness as 3 when the pressure of the tire 202 is lower and as 2 when the pressure of the tire 202 is higher. In this way, by using the pressure of the tire 202 as a basis, the road surface condition identification unit 266 can identify the road surface condition with a more accurate numerical value.
[0040] The road surface condition identification unit 266 may also identify the condition of the road surface 104 on which the vehicle 102 has traveled, based on tire usage information. The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the ambient temperature of the tire 202 measured by the temperature sensor 232. The higher the ambient temperature of the tire 202, the higher the temperature of the tread portion of the tire 202, and the softer the rubber material of the tread portion becomes. As a result, the tread portion absorbs shocks better, and the amount of pressure fluctuation of the fluid pressure suspension 204 becomes smaller. Therefore, the road surface condition identification unit 266 may identify the condition of the road surface 104 such that the degree of unevenness of the identified road surface 104 becomes greater the higher the ambient temperature of the tire 202. For example, when the values of the indices showing the variation in multiple pressures of the fluid pressure suspension 204 are the same when the ambient temperature of the tire 202 is lower and when it is higher, the road surface condition identification unit 266 identifies the degree of unevenness as 2 when the ambient temperature of the tire 202 is lower, and as 3 when the ambient temperature of the tire 202 is higher. In this way, by basing the road surface condition identification unit 266 on the ambient temperature of the tire 202, it can identify the road surface condition with a more accurate numerical value.
[0041] The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the total mileage of the tires 202 measured by the odometer 234 or the total service life of the tires 202 measured by the timer 236. The longer the total mileage of the tires 202 or the longer the total service life of the tires 202, the more the tread portion of the tires 202 is worn and the greater the reduction in the thickness of the tread portion. As a result, the tread portion absorbs shocks less effectively, and the amount of pressure fluctuation in the fluid pressure suspension 204 becomes larger. Therefore, the road surface condition identification unit 266 may identify the condition of the road surface 104 such that the degree of unevenness of the identified road surface 104 becomes smaller as the total mileage of the tires 202 or the total service life of the tires 202 increases. For example, when the values of the indices showing the variation in multiple pressures of the fluid pressure suspension 204 are the same for both shorter and longer total mileage or total usage period of the tire 202, the road surface condition identification unit 266 identifies the degree of unevenness as 3 when the total mileage or total usage period of the tire 202 is shorter, and as 2 when the total mileage or total usage period of the tire 202 is longer. In this way, by basing the road surface condition identification unit 266 on the total mileage or total usage period of the tire 202, it can identify the road surface condition with a more accurate numerical value.
[0042] The road surface condition identification unit 266 may further identify the condition of the road surface 104 based on vehicle condition information. The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the speed of the vehicle 102 measured by the speed sensor 242. The higher the speed of the vehicle 102, the greater the impact the vehicle 102 receives, and the greater the fluctuation in pressure of the fluid pressure suspension 204. Therefore, the road surface condition identification unit 266 may identify the condition of the road surface 104 such that the degree of unevenness of the identified road surface 104 decreases as the speed of the vehicle 102 increases. For example, if the values of the indices showing the variation in multiple pressures of the fluid pressure suspension 204 are the same when the speed of the vehicle 102 is lower and when it is higher, the road surface condition identification unit 266 may identify the degree of unevenness as 3 when the speed of the vehicle 102 is lower and as 2 when the speed of the vehicle 102 is higher. In this way, by using the speed of the vehicle 102 as a basis, the road surface condition identification unit 266 can identify the road surface condition with a more accurate numerical value.
[0043] The road surface condition identification unit 266 may identify the condition of the road surface 104 based on the lateral acceleration of the vehicle 102. An example of the lateral acceleration of the vehicle 102 is the centrifugal acceleration of the vehicle. When the vehicle 102 is turning, it experiences lateral acceleration, i.e., outward centrifugal acceleration. The magnitude of the centrifugal acceleration can be calculated from the speed of the vehicle 102 measured by the speed sensor 242 and the steering angle of the vehicle 102 measured by the steering angle sensor 248. Instead of either the speed or the steering angle of the vehicle 102, the angular velocity of the vehicle 102 measured by the angular velocity sensor 246 may be used. The lateral acceleration of the vehicle 102 may also be measured by the acceleration sensor 244.
[0044] As the lateral acceleration of the vehicle 102 increases, the vehicle 102 receives a greater lateral inertial force, causing the vehicle 102 to tilt more. As a result, the balance of the loads applied to the tires 202 of the vehicle 102 fluctuates more, causing the pressure of the hydraulic suspension 204 to fluctuate more. Therefore, the road surface condition specifying unit 266 may correct the pressure of the hydraulic suspension 204 on the lower side to be lower or the pressure of the hydraulic suspension 204 on the upper side to be higher as the lateral acceleration of the vehicle 102 increases due to the tilt of the vehicle 102. The road surface condition specifying unit 266 may specify the degree of unevenness of the road surface 104 based on the corrected pressure of the hydraulic suspension 204.
[0045] The road surface condition specifying unit 266 may specify the condition of the road surface 104 based on the load of the vehicle 102. As the load of the vehicle 102 increases, the amount of pressure fluctuation of the hydraulic suspension 204 becomes smaller. Therefore, the road surface condition specifying unit 266 may specify the condition of the road surface 104 such that the degree of unevenness of the specified road surface 104 increases as the load of the vehicle 102 increases. For example, when the value of an index indicating the variation in the pressures of the plurality of hydraulic suspensions 204 is the same when the load of the vehicle 102 is smaller and when it is larger, the road surface condition specifying unit 266 specifies the degree of unevenness when the load of the vehicle 102 is smaller as 2 and the degree of unevenness when the load of the vehicle 102 is larger as 3. In this way, by basing on the load of the vehicle 102, the road surface condition specifying unit 266 can specify the condition of the road surface with a higher degree of accuracy.
[0046] The road surface condition specifying unit 266 may also specify the condition of the road surface 104 based on the tire information of the tire 202. The road surface condition specifying unit 266 may specify the condition of the road surface 104 such that, for example, the degree of unevenness of the specified road surface 104 increases as the size of the tire 202 increases. The road surface condition specifying unit 266 may specify the condition of the road surface 104 such that, for example, the degree of unevenness of the specified road surface 104 increases as the material of the rubber material of the tire 202 becomes softer.
[0047] The road surface state specifying unit 266 specifies the position of the road surface 104 based on the position information of the vehicle 102. The road surface state specifying unit 266 outputs road surface state information indicating the state of the road surface 104 for each position of the road surface 104 to the communication control unit 268. The position information of the vehicle 102 is, for example, information indicating the latitude and longitude at which the vehicle 102 is located.
[0048] The communication control unit 268 outputs the road surface state information output from the road surface state specifying unit 266 to the communication device 280. Here, "output" means outputting to the outside of the control device 260, and it is a concept that includes not only visually displaying or transmitting via a communication network but also delivering to various controllers other than the control device 260. The communication device 280 transmits the road surface state information to the management device 108 or the data server 110.
[0049] The communication control unit 268 receives the road surface report transmitted from the management device 108 via the communication device 280. The communication control unit 268 transfers the road surface report to the output control unit 270. The output control unit 270 outputs the road surface report transferred from the communication control unit 268 to the output device 290. The output device 290 outputs the road surface report to the operator of the vehicle 102. The output device may be a display device that displays the road surface report.
[0050] According to the present embodiment, since the state of the road surface 104 is specified based on the tire behavior information and the tire state information, the state of the road surface 104 is specified more accurately than when the state of the road surface 104 is specified only based on the tire behavior state. Since both the temperature and pressure of the tire 202 can be used as the tire state information, the state of the road surface 104 is specified even more accurately. Further, by specifying the state of the road surface 104 based on the tire behavior information, the tire usage information, the tire state information, and the vehicle state information, the state of the road surface 104 is specified even more accurately. Since the operator of the vehicle 102 can check the road surface report and select a traveling road with a good road surface state for traveling, damage to the tire 202 can be reduced. Workers at the work site, such as users of the management device 108, check the road surface report and level the road surface using a vehicle such as a motor grader. Therefore, road surface maintenance can be quickly performed.
[0051] The road surface condition identification unit 266 may output the identified road surface condition information of the road surface 104 to the output control unit 270. The communication control unit 268 may transfer the road surface condition information of the road surface 104 received from the management device 108 or data server 110 via the communication device 280 to the output control unit 270. If the road surface condition information output from the road surface condition identification unit 266 or transferred from the communication control unit 268 satisfies predetermined conditions, the output control unit 270 may output a control command for the vehicle 102 from the output device 290. The output device 290 may be a driving control controller that controls the vehicle 102. The control command is, for example, a control command that changes the maximum vehicle speed set for the vehicle 102 or the driving speed of the vehicle 102 while it is in motion. The control command may be a control command that reduces the maximum vehicle speed set for the vehicle 102, or a control command that decelerates the vehicle 102 while it is in motion. In particular, it can automatically slow down unmanned vehicles when they are traveling on poor road surfaces, thus helping to avoid accidents involving unmanned vehicles.
[0052] The road surface condition identification unit 266 may calculate a road surface score for a predetermined geographical area including the road surface 104 based on the road surface condition information. For example, the road surface condition identification unit 266 calculates the average value of the road surface condition information for each geographical area of a predetermined size as the road surface score for the road surface 104.
[0053] The road surface condition identification unit 266 calculates the road surface score of the road surface 104 by, for example, averaging the road surface scores of the locations included in a predetermined geographical area of a predetermined size, using the average value of the road surface condition information output from the information storage unit 264 within a predetermined period. The road surface condition identification unit 266 calculates the road surface score of the road surface 104 by, for example, averaging the road surface scores of the locations included in a predetermined geographical area of a predetermined size, using the average value of the road surface condition information output from the information storage unit 264 up to the time of road surface score calculation. The road surface condition identification unit 266 calculates the road surface score of the road surface 104 by, for example, averaging the road surface scores of the locations included in a predetermined geographical area.
[0054] The output control unit 270 generates a road surface report based on the road surface score calculated by the road surface condition identification unit 266. The output control unit 270 outputs the road surface report to the output device 290. The output device 290 outputs the road surface report output from the output control unit 270 to the operator of the vehicle 102.
[0055] In vehicle 102, as soon as the road surface condition identification unit 266 identifies the road surface condition, the output device 290 can output a road surface report. Therefore, the operator of vehicle 102 can recognize the road surface condition even at work sites outside the coverage area of the communication network 106.
[0056] The communication control unit 268 may transmit tire behavior information, tire condition information, tire usage information, and vehicle condition information stored in the information storage unit 264 from the communication device 280 to the management device 108 or data server 110 for the purpose of allowing the management device 108 to identify the condition of the road surface 104. Even if the control device 260 of the vehicle 102 does not have a function to identify the condition of the road surface, the management device 108 can identify the condition of the road surface. In addition, since the condition of the road surface is identified in the management device 108, the computational load on the control device 260 of the vehicle 102 is reduced.
[0057] Figure 3 shows the configuration of the management device 108 according to this embodiment. The management device 108 includes a communication unit 310, an information acquisition unit 362, an information storage unit 364, a road surface condition identification unit 366, and an output unit 320. The information acquisition unit 362, the information storage unit 364, and the road surface condition identification unit 366 may each have the same functions as the information acquisition unit 262, the information storage unit 264, and the road surface condition identification unit 266.
[0058] First, the operation of the management device 108 in generating a road surface report based on road surface condition information provided by the vehicles will be explained. The communication unit 310 receives road surface condition information from multiple vehicles, including vehicle 102, or from the data server 110, and transfers it to the information acquisition unit 362. The information acquisition unit 362 acquires the transferred road surface condition information and stores it in the information storage unit 364. The road surface condition identification unit 366 calculates the road surface score of the road surface 104 based on the road surface condition information stored in the information storage unit 364.
[0059] The road surface condition identification unit 366 calculates the road surface score of the road surface 104 by taking the average value of the road surface condition information output from multiple vehicles, including vehicle 102, for each geographic area of a predetermined size. The geographic area of a predetermined size is, for example, a rectangular area of 50 meters on each side. The road surface condition identification unit 366 calculates the road surface score of the road surface 104 by taking the average value of the road surface condition information output from multiple vehicles, including vehicle 102, for each geographic area of a predetermined size within a predetermined period of time for the locations included in that area. The road surface condition identification unit 366 calculates the road surface score of the road surface 104 by taking the average value of the road surface condition information output from multiple vehicles, including vehicle 102, for each geographic area of a predetermined size up to the time of calculating the road surface score. The road surface condition identification unit 366 calculates the road surface score of the road surface 104 by, for example, using the average value of the road surface condition information output from multiple vehicles, including vehicle 102, within a predetermined continuous period up to the time of calculation of the road surface score for each geographic area of a predetermined size. The road surface condition identification unit 366 calculates the road surface score for a predetermined geographic area by, for example, averaging the road surface scores of each location included within the predetermined geographic area.
[0060] The road surface condition identification unit 366 generates a road surface report based on the road surface score and outputs it to the output unit 320 or the communication unit 310. The output unit 320 outputs the road surface report to the user of the management device 108. Here, "output" means outputting to an external location of the management device 108, and this concept includes not only visual display or transmission via a communication network, but also handing it over to various controllers other than the management device 108. The communication unit 310 outputs the road surface report to vehicle 102 or vehicle 112. The communication unit 310 may also output the road surface report to the data server 110.
[0061] The management device 108 can provide road surface reports even to vehicles that have not provided road surface condition information. For example, it can provide road surface reports regarding the roads at a work site to multiple vehicles working at that work site. Furthermore, by storing the road surface reports in the data server 110, the road surface reports can be provided not only to the administrator of the management device 108 but also to anyone who requests them.
[0062] Next, the operation of the management device 108 to output road surface condition information of the road surface 104 based on tire behavior information, tire condition information, tire usage information, and vehicle condition information collected by the vehicle 102 will be explained. The communication unit 310 receives various information collected by the vehicle 102 from the vehicle 102 or the data server 110 and transfers it to the information acquisition unit 362. The information acquisition unit 362 acquires the various information and stores it in the information storage unit 364.
[0063] The road surface condition identification unit 366 identifies the condition of the road surface 104 based on various information stored in the information storage unit 364. The road surface condition identification unit 366 calculates a road surface score based on the road surface condition information and generates a road surface report. The road surface condition identification unit 366 may output the road surface condition information to the communication unit 310. The communication unit 310 may output the road surface condition information to the vehicle 102 or the data server 110.
[0064] Even if the control device 260 of the vehicle 102 does not have a function to identify the road surface condition, the management device 108 can identify the road surface condition. Furthermore, since the road surface condition is identified by the management device 108, the computational load on the control device 260 of the vehicle 102 is reduced.
[0065] Figure 4 shows an example of a road surface report. The road surface report shows the road surface score for each rectangular area on a map that includes work site 502, work site 504, road 506, and road 508. The road surface score is described on a scale of 6 from 0 to 5. Within work site 502 and work site 504, the road surface score for each rectangular area is 2 or 3. Within road 506, the road surface score for each rectangular area is 4 or 5. Within road 508, the road surface score for each rectangular area is 0 or 1. The road surface report may also show the road surface score for each area of work site 502, work site 504, road 506, and road 508, rather than the road surface score for each rectangular area.
[0066] By referring to the road surface report, it is possible to select the road 506 with good road conditions when moving from work site 502 to work site 504. Therefore, damage to the tires caused by traveling on the road 508 with poor road conditions can be reduced.
[0067] Figure 5 shows an example of the processing flow of the control device 260 according to this embodiment. In step 600, the information acquisition unit 262 acquires tire behavior information indicating the behavior of the tires 202 of the vehicle 102 from the measuring device 210 and stores it in the information storage unit 264. In step 602, the information acquisition unit 262 acquires tire state information indicating the state of the tires 202 from the detection device 220 and stores it in the information storage unit 264. In step 606, the information acquisition unit 262 acquires position information of the vehicle 102 from the position sensor 250 and stores it in the information storage unit 264.
[0068] In step 606, the road surface condition identification unit 266 identifies the condition of the road surface 104 that the vehicle 102 has traveled on, based on the tire behavior information, tire condition information, and position information stored in the information storage unit 264, and outputs road surface condition information indicating the condition of the road surface 104 for each location on the road surface 104. In step 608, the communication control unit 268 causes the communication device 280 to transmit the road surface condition information to the management device 108 or the data server 110. In step 610, the communication control unit 268 receives the road surface report generated by the management device 108 based on the road surface condition information from the management device 108 via the communication device 280 and forwards it to the output control unit 270. In step 612, the output control unit 270 causes the road surface report to output device 290.
[0069] Figure 6 shows an example of a computer 1200 in which this embodiment may be embodied in whole or in part. A program installed on the computer 1200 can cause the computer 1200 to function as an operation or one or more sections of the apparatus according to this embodiment, or to execute such operation or one or more sections, and / or to cause the computer 1200 to execute a process or a stage of such process according to this embodiment. Such a program may be executed by the CPU 1212 to cause the computer 1200 to perform a specific operation associated with some or all of the blocks of the flowcharts and configuration diagrams described herein.
[0070] The computer 1200 according to this embodiment includes a CPU 1212, RAM 1214, a graphics controller 1216, and a display device 1218, which are interconnected by a host controller 1210. The computer 1200 includes a communication interface 1222, a storage device 1224 such as a hard disk drive, an input / output unit such as a DVD-ROM drive 1226, and an IC card drive, which are connected to the host controller 1210 via an input / output controller 1220. The computer also includes legacy input / output units such as a ROM 1230 and a keyboard 1242, which are connected to the input / output controller 1220 via an input / output chip 1240.
[0071] The CPU 1212 operates according to the programs stored in the ROM 1230 and RAM 1214, thereby controlling each unit. The graphics controller 1216 acquires image data generated by the CPU 1212 from the frame buffer provided in the RAM 1214 or from itself, and displays the image data on the display device 1218.
[0072] The communication interface 1222 communicates with other electronic devices via a network. The storage device 1224 stores programs and data used by the CPU 1212 in the computer 1200. The DVD-ROM drive 1226 reads programs or data from the DVD-ROM 1227 and provides them to the storage device 1224 via the RAM 1214. The IC card drive reads programs and data from the IC card and / or writes programs and data to the IC card.
[0073] The ROM 1230 stores boot programs and / or programs that depend on the computer 1200's hardware, which are executed by the computer 1200 when activated. The input / output chip 1240 may connect various input / output units to the input / output controller 1220 via a parallel port, serial port, keyboard port, mouse port, etc.
[0074] The program is provided on a computer-readable medium such as a DVD-ROM 1227 or an IC card. The program is read from the computer-readable medium and installed on a storage device 1224, RAM 1214, or ROM 1230, which are examples of computer-readable mediums, and executed by the CPU 1212. The information processing described within these programs is read by the computer 1200, resulting in coordination between the program and the various types of hardware resources described above. The apparatus or method may be configured to realize the manipulation or processing of information in accordance with the use of the computer 1200.
[0075] For example, when communication is performed between a computer 1200 and an external device, the CPU 1212 may execute a communication program loaded into the RAM 1214 and, based on the processing described in the communication program, instruct the communication interface 1222 to perform communication processing. Under the control of the CPU 1212, the communication interface 1222 reads transmission data stored in a transmission buffer processing area provided in a recording medium such as the RAM 1214, storage device 1224, DVD-ROM 1227, or IC card, transmits the read transmission data to the network, or writes received data received from the network to a receive buffer processing area provided on the recording medium.
[0076] The CPU 1212 may read all or necessary parts of a file or database stored on an external recording medium such as a storage device 1224, a DVD-ROM drive 1226 (DVD-ROM 1227), or an IC card into the RAM 1214, and perform various types of processing on the data in the RAM 1214. The CPU 1212 then writes the processed data back to the external recording medium.
[0077] Various types of information, such as various types of programs, data, tables, and databases, may be stored on the recording medium and subjected to information processing. The CPU 1212 may perform various types of processing on the data read from the RAM 1214, including various types of operations, information processing, conditional judgments, conditional branching, unconditional branching, information retrieval / replacement, etc., as described throughout this disclosure and specified by the program instruction sequence, and write the results back to the RAM 1214. The CPU 1212 may search for information in files, databases, etc., within the recording medium. For example, if a plurality of entries having attribute values of a first attribute, each associated with an attribute value of a second attribute, are stored in the recording medium, the CPU 1212 may search among the plurality of entries for an entry that matches the condition for which the attribute value of the first attribute is specified, read the attribute value of the second attribute stored in that entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.
[0078] The programs or software modules described above may be stored on or near the computer 1200 on a computer-readable medium. A recording medium such as a hard disk or RAM provided within a server system connected to a dedicated communication network or the Internet can be used as a computer-readable medium, thereby providing the programs to the computer 1200 via the network.
[0079] Although the invention has been described using embodiments, the technical scope of the present invention is not limited to the scope described in the embodiments above. It will be apparent to those skilled in the art that various modifications or improvements can be made to the embodiments described above. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.
[0080] It should be noted that the execution order of operations, procedures, steps, and stages in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before" or "prior to," and can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc., for convenience, this does not mean that it is mandatory to perform the operations in that order.
[0081] 100 Vehicle management system, 102 Vehicle, 104 Road surface, 106 Communication network, 108 Management device, 110 Data server, 112 Vehicle, 202 Tire, 204 Fluid pressure suspension, 206 Frame, 210 Measurement device, 212 Acceleration sensor, 214 Pressure sensor, 216 Strain sensor, 220 Detection device, 222 Temperature sensor, 224 Pressure sensor, 230 Usage status acquisition device, 232 Temperature sensor, 234 Odometer, 236 Timer, 240 Vehicle status acquisition device, 242 Speed sensor, 244 Acceleration sensor, 246 Angular velocity sensor, 248 Steering angle sensor, 250 Position sensor, 252 Clock, 260 Control device, 262 Information acquisition unit, 264 Information storage unit, 266 Road surface condition identification unit, 268 Communication control unit, 270 Output control unit, 280 Communication device, 290 Output device, 310 Communication unit, 320 Output unit, 362 Information acquisition unit, 364 Information storage unit, 366 Road surface condition identification unit, 502 Work site, 504 Work site, 506 Driving path, 508 Driving path, 1200 Computer, 1210 Host controller, 1212 CPU, 1214 RAM, 1216 Graphics controller, 1218 Display device, 1220 Input / output controller, 1222 Communication interface, 1224 Storage device, 1226 DVD-ROM drive, 1227 DVD-ROM, 1230 ROM, 1240 Input / output chip, 1242 Keyboard
Claims
1. A road surface condition identification system comprising at least one processor, wherein the at least one processor acquires tire behavior information indicating the behavior of the tires of a vehicle and tire condition information indicating the state of the tires, identifies the state of the road surface on which the vehicle has traveled based on the tire behavior information and the tire condition information, and outputs road surface condition information indicating the state of the road surface.
2. The road surface condition identification system according to claim 1, wherein the tire behavior information includes information indicating the pressure of a fluid pressure suspension connected to the tire.
3. The road surface condition identification system according to claim 1, wherein the tire behavior information includes information indicating the acceleration of the tire.
4. The road surface condition identification system according to claim 1, wherein the tire behavior information includes information indicating the strain of the vehicle's frame.
5. The road surface condition identification system according to claim 1, wherein the tire condition information includes information indicating the pressure of the tire.
6. The road surface condition identification system according to claim 1, wherein the tire condition information includes information indicating the temperature of the tire.
7. The road surface condition identification system according to claim 1, wherein the at least one processor acquires tire usage information indicating the usage status of the tire, and identifies the condition of the road surface over which the vehicle has traveled based on the tire usage information, the tire behavior information, and the tire condition information.
8. The road surface condition identification system according to claim 7, wherein the tire usage information includes information indicating the period of use of the tire or the outside temperature of the tire.
9. The road surface condition identification system according to claim 1, wherein the at least one processor acquires vehicle state information indicating the state of the vehicle, and identifies the state of the road surface on which the vehicle has traveled based on the vehicle state information, the tire behavior information, and the tire state information.
10. The road surface condition identification system according to claim 9, wherein the vehicle condition information includes information indicating the speed of the vehicle or information indicating the load of cargo loaded on the vehicle.
11. The road surface condition identification system according to any one of claims 1 to 10, wherein the at least one processor acquires location information indicating the position of the vehicle, identifies the position of the road surface on which the vehicle has traveled based on the location information, and outputs road surface condition information indicating the state of the road surface for each position of the road surface.
12. The road surface condition identification system according to claim 11, wherein the at least one processor causes a display device to display an image representing the condition of the road surface at the location of the road surface on the map.
13. A vehicle comprising a tire, a measuring device for measuring the behavior of the tire, a detection device for detecting the state of the tire, and the road surface condition identification system according to claim 1.
14. The vehicle according to claim 13, further comprising a fluid pressure suspension connected to the tire, wherein the measuring device has a pressure sensor for measuring the pressure of the fluid pressure suspension, and the tire behavior information includes information indicating the pressure of the fluid pressure suspension connected to the tire.
15. The vehicle according to claim 13, wherein the measuring device has an acceleration sensor attached to the tire for measuring the acceleration of the tire, and the tire behavior information includes information indicating the acceleration of the tire.
16. The vehicle according to claim 13, wherein the measuring device has a strain sensor for measuring the strain of the vehicle's frame, and the tire behavior information includes information indicating the strain of the vehicle's frame.
17. The vehicle according to claim 13, wherein the detection device has a pressure sensor for measuring the pressure of the tire, and the tire condition information includes information indicating the pressure of the tire.
18. The vehicle according to claim 13, wherein the detection device has a temperature sensor for measuring the temperature of the tire, and the tire condition information includes information indicating the temperature of the tire.
19. A program for causing a computer to function as a road surface condition identification system according to any one of claims 1 to 9.
20. A method for identifying road surface conditions, comprising: acquiring tire behavior information indicating the behavior of the tires of a vehicle and tire condition information indicating the state of the tires; identifying the state of the road surface on which the vehicle has traveled based on the tire behavior information and the tire condition information; and outputting road surface condition information indicating the state of the road surface.