JP2023078986A - Road surface condition acquiring system - Google Patents

Abstract

To ensure that a road surface condition within an area is acquired satisfactorily.SOLUTION: A road surface condition, which is a condition of a road surface, is acquired for each of a plurality of moving objects, and moving object information including road surface condition information, which is information for representing the road surface condition, is transmitted. A central control device receives the moving object information and transmits central control information including a movement command to at least one of the plurality of moving objects based on the moving object road surface condition information included in the moving object information. The central control device, for example, forms the movement command so that the road surface condition is acquired in good condition. Then, at least one of the moving objects moves according to the movement command, acquires the road surface condition, and transmits the road surface condition information. The central control device receives the moving object information and acquires the road surface condition. In this way, based on the road surface condition information from the moving object which has moved according to the movement command formed by the central control device, it is possible to acquire the road surface condition within the area satisfactorily.SELECTED DRAWING: Figure 3

Description

The present invention relates to a road surface condition acquisition system for acquiring road surface conditions.

In Patent Document 1, wireless communication is performed between a transport vehicle, which is a vehicle that performs mining work, and a control terminal, and the control terminal receives information from the transport vehicle (the position of the transport vehicle, the deterioration state of the road surface, etc.). It describes that the map information is created based on the indicated value, the time). In addition, the transportation vehicle acquires map information stored in the control terminal and travels based on the map information. For example, in a delivery vehicle, it is determined whether or not it is possible to travel according to the planned travel progress based on the map information, and based on the determination result, avoidance is performed by steering or the vehicle is traveled at a reduced speed.

JP 2020-50193

SUMMARY OF THE INVENTION It is an object of the present invention to acquire a good road surface condition in a road surface condition acquisition system that acquires the road surface condition, which is the condition of the road surface in an area where a moving object moves.

Means, actions and effects for solving problems

In the road surface condition acquisition system according to the present invention, the road surface condition is acquired for each of a plurality of mobile objects, and mobile object information including road surface condition information representing the road surface condition is created and transmitted. The central control device receives the mobile object information, and creates and transmits central control information including a movement command to at least one of the plurality of mobile objects based on the road surface condition information included in the mobile object information.

The central control unit can, for example, create movement commands so that good road conditions are obtained. The moving object moves according to the movement command, acquires the road surface condition, creates and transmits moving object information including the road surface condition information. The central control device receives the moving body information and acquires the road surface condition. In this way, based on the road surface conditions acquired by the moving object that has moved in accordance with the movement command created by the central control device, it is possible to acquire the road surface conditions within the area satisfactorily.

In addition, for example, the central control device moves to a moving body that moves toward a portion of the road surface with large unevenness or a portion with a low coefficient of friction of the road surface among the plurality of moving bodies, while avoiding that portion. It is possible to create a movement command or a movement command to move at a reduced speed. As a result, it is possible to improve the safety of each of the plurality of moving bodies. In addition, it is possible to make it difficult for each of the plurality of moving bodies to become stuck, and it is possible to satisfactorily suppress a decrease in work efficiency in the area.

1 is a diagram conceptually showing a road surface condition acquisition system that is an embodiment of the present invention; FIG. The road surface condition acquisition system includes a management system that is one embodiment of the present invention. FIG. 2 is a diagram conceptually showing a drive/transmission device, a braking device, and a steering device provided in a vehicle as a mobile body included in the road surface condition acquisition system; FIG. 2 is a diagram conceptually showing the periphery of a control device of the road surface condition acquisition system; (a) A diagram showing changes in longitudinal force acting between wheels and a road surface over time. (b) A diagram showing the relationship between the longitudinal force acting between the wheel and the road surface and the slip ratio. 4 is a flowchart showing a vehicle μ acquisition program stored in the vehicle ECU of the road surface condition acquisition system; 4 is a flowchart showing a vehicle information creation program stored in the vehicle ECU; 4 is a flowchart representing a remote control program stored in the vehicle ECU; 4 is a flow chart showing a central control information creation program stored in a central control ECU of the road surface condition acquisition system; 4 is a flow chart showing a management program stored in the central control ECU; 4 is a flow chart showing another road surface μ-related state acquisition program stored in the vehicle ECU; FIG. 4 is a diagram conceptually showing another drive/transmission device included in the vehicle;

A road surface condition acquisition system according to an embodiment of the present invention will be described below with reference to the drawings. The road surface condition acquisition system includes a management system.

As shown in FIG. 1, the road surface condition acquisition system according to the present embodiment includes, for example, a plurality of mobile bodies such as a vehicle V for working in a mine or the like, a central control device C capable of communicating with the vehicle V, one or more Antenna A etc. are included. Wireless communication is performed directly or via an antenna A between the plurality of vehicles V and the central control device C. Moreover, most of the plurality of vehicles V are vehicles of the same kind and the same model.

Each of the plurality of vehicles V includes four wheels 10FL, 10FR, 10RL, and 10RR positioned on the front, rear, left, and right, as shown in FIG. These four wheels 10FL, 10FR, 10RL, and 10RR are drive wheels, and each of the plurality of vehicles V is a four-wheel drive vehicle. Also, the left and right front wheels 10FL and 10FR are steered wheels, and the vehicle is a front wheel steering vehicle.
Furthermore, although each of the plurality of vehicles V is an automatically driving vehicle capable of automatically driving, it is not limited thereto. Each of the plurality of vehicles V may be a manually operated vehicle capable of manual operation or a vehicle capable of being switched between an automatic operation state and a manual operation state. Further, each of the plurality of vehicles V may be in a manned running state or an unmanned running state.

Hereinafter, subscripts FL, FR, RL, RR, F, and R representing wheel positions of wheels, brakes, etc. are omitted when they are generically used and when wheel positions are not specified.

Each of the plurality of vehicles V includes a drive/transmission device D, a braking device B, a steering device ST, etc., as shown in FIG.

The drive/transmission device D transmits the drive torque output by the drive source 13 including the engine 11 and the electric motor 12 to the front, rear, left, and right wheels 10 serving as drive wheels. The drive/transmission device D includes a drive source 13, a main transmission path 16 that transmits the drive torque of the drive source 13 to the left and right front wheels 10FL and 10FR, and a secondary transmission path that transmits the drive torque of the drive source 13 to the left and right rear wheels 10RL and 10RR. and transmission path 18 .

The main transmission path 16 includes a transmission 20 connected to the drive source 13, a front wheel differential 22, drive shafts 24FL and 24FR connected to the left and right front wheels 10FL and 10FR, and the like. The auxiliary transmission path 18 includes a transmission 20, a transfer 26, a propeller shaft 28, a rear wheel side differential 30, drive shafts 32RL and 32RR connected to the left and right rear wheels 10RL and 10RR, and the like.

Drive source 13 includes engine 11, electric motor 12, power split device 34, generator 35, inverters 36M and 36G, and the like.
The power split device 34 splits the rotation of the engine 11 into the rotation of the generator 35 and the rotation of the output shaft of the power split device 34. The output shaft of the power split device 34 is provided with the transmission 20. . An electric motor 12 is connected to the transmission 20, and the output shaft of the transmission 20 is connected to the left and right front wheels 10FL and 10FR via a front wheel side differential gear 22 and drive shafts 24FL and 24FR. The generator 35 and the electric motor 12 are connected to the battery 38 via inverters 36G and 36M, respectively. The battery 38 supplies electric energy to the electric motor 12 and the like, and stores the electric energy obtained by the electric motor 12 and the generator 35 . The operations of the generator 35 and the electric motor 12 are controlled by the control of inverters 36M and 36G, respectively.

The transfer 26 distributes the output of the drive source 13 to the left and right rear wheels 10RL and 10RR. The output of the drive source 13 is transmitted to the front, rear, left, and right wheels 10FL, 10FR, 10RL, and 10RR by the transfer 26 and the like (4-wheel drive state), and the state of transmission to the left and right front wheels 10FL, 10FR (2-wheel drive state). state).
The front-wheel-side differential 22 and the rear-wheel-side differential 30 may each include, for example, a differential gear.

In the four-wheel drive state, the driving torque of at least one of the engine 11 and the electric motor 12 is transmitted to the front, rear, left, and right wheels 10FL, 10FR, 10RL, and 10RR. is transmitted to Further, due to the regenerative braking of the electric motor 12, regenerative braking torque is applied to the front, rear, left, and right four wheels 10FL, 10FR, 10RL, and 10RR or the left and right front wheels 10FL, 10FR. From this, it can be considered that the drive source 13 is a regenerative braking device.

The braking device B includes a regenerative braking device 13, a hydraulic braking device 41 as a friction braking device, and the like. The hydraulic braking device 41 includes a hydraulic brake 40 as a friction brake provided for each of the plurality of wheels 10, a hydraulic control actuator 46, and the like. The hydraulic brake 40 includes a brake rotor 42 rotatable integrally with the wheel 10, a pair of frictional engagement members 43 provided facing the brake rotor 42, and a pair of frictional engagement members 43 by hydraulic pressure. and a pressing device 44 that presses the mating member 43 against the brake rotor 42 . A hydraulic control actuator 46 is connected to the pressing device 44 of each of the plurality of hydraulic brakes 40 . The hydraulic pressure control actuator 46 generates hydraulic pressure and can independently control the hydraulic pressure of the hydraulic brakes 40 of the front, rear, left, and right wheels 10 .

The steering device ST is provided by connecting the left and right front wheels 10FL and 10FR, and steers the pair of left and right front wheels 10 by moving the steering shaft in the lateral direction of the vehicle.
The left and right front wheels 10FL and 10FR are respectively connected by knuckle arms 52FL and 52FR of knuckles (not shown) that hold the wheels, tie rods 54FL and 54FR, a steering shaft 56, etc. A steering actuator 60 is provided on the steering shaft 56. be done. The steering actuator 60 includes an electric motor (not shown) and a motion conversion mechanism that converts rotation of the electric motor into movement of the steering shaft 56 in the axial direction (the width direction of the vehicle). The steering actuator 60 moves the steering shaft 54 in the axial direction with respect to the vehicle body to steer the pair of left and right front wheels 10 . The steering angle of the left and right front wheels 10 is determined by the operating state of the steering actuator 60 .

Each of the plurality of moving bodies V includes a vehicle ECU 80 mainly composed of a computer, as shown in FIG. 3 . The vehicle ECU 80 includes an identification information storage unit 82, a mobile road surface condition acquisition unit (hereinafter simply referred to as a road surface condition acquisition unit) 84, a travel control unit 86, and a vehicle information creation unit that creates vehicle information as mobile object information. 88, etc. The vehicle ECU 80 also includes wheel speed sensors 90FL, 90FR, 90RL, and 90RR, which are provided for the front, rear, left, and right wheels 10 and detect the rotational speed of the wheels 10, respectively, and a yaw rate, which is the rotational angular speed of the vehicle V around the vertical axis. A yaw rate sensor 92 for detecting , a G sensor 94 which is an acceleration sensor for detecting acceleration in the longitudinal direction and the lateral direction of the vehicle V, etc. are connected, and the engine 11, the inverter 36M, the transfer 26, etc. of the drive/transmission device D are connected. The hydraulic control actuator 46 of the hydraulic braking device 41 of the braking device B, the regenerative braking device 13, the steering actuator 60 of the steering device ST, and the like are connected. In addition, a peripheral information acquisition device 102, a GPS (Global Positioning System) receiver 104, a notification device 106, a vehicle communication device 108 as a mobile communication device, and a plurality of other measuring devices 110 are connected.

The peripheral information acquisition device 102 includes a camera, a radar device, and the like, identifies objects around the own vehicle, which is the vehicle V, and acquires the relative positional relationship between the objects and the own vehicle. In addition, it is also possible to obtain the road surface condition using a camera, a radar device, or the like.
The GPS receiver 104 receives GPS signals, and the position of the own vehicle, which is the vehicle V, is obtained based on the received signals.
The plurality of measuring devices 110 include a device that measures the state of charge of the battery 38, a device that measures the amount of oil supplied to the fuel tank, and the like.

The vehicle communication device 108 transmits vehicle information as mobile information, which is information created in the vehicle V, and receives central control information, which is information transmitted from the central control device C. . These mobile information and central control information are often transmitted and received via the antenna A.
The notification device 106 includes, for example, a display, an audio output device, etc., and can notify the content of the central control information received from the central control device C by the vehicle communication device 108 .

The identification information etc. storage unit 82 stores identification information etc. set for the vehicle V. FIG. Each of the plurality of vehicles V is given identification information different from each other, and is managed based on the identification information. In addition, the weight, position, etc. of the load (luggage) loaded by each of the vehicles V are also stored in the identification information etc. storage unit 82 in association with the identification information.

The traveling control unit 86 controls the engine 11, the transfer 26, the inverter 36M of the drive/transmission device D, the hydraulic pressure control actuator 46 of the braking device B, the regenerative braking device 13, the steering actuator 60 of the steering device ST, and the like. , to control the running state of the vehicle V. The travel control unit 86 controls these based on the relative positional relationship between the own vehicle and surrounding objects acquired by the surrounding information acquisition device 102, and controls the own vehicle V to travel along a predetermined route. or based on a travel command as a movement command included in the central control information.

The road surface condition acquiring unit 84 acquires the road surface μ, which is the coefficient of friction of the road surface on which the vehicle V travels, or a condition related to the road surface μ (together, these are referred to as a related condition such as the road surface μ). is. The related state such as the road surface μ can be represented by the road surface μ, a state where the road surface μ is small, a state where the road surface μ is large, or the like.

In this embodiment, the road surface condition acquisition unit 84 acquires the road surface μ as the related condition such as the road surface μ.
As shown in FIGS. 4(a) and 4(b), the road surface μ is the longitudinal force F when the longitudinal force acting between the wheel 10 and the road surface (which can be referred to as frictional force) is saturated. It is obtained as a value divided by the load N of the wheel 10 .
μ = F/N
The saturated back-and-forth force, which is the saturated back-and-forth force, is the maximum frictional force. Further, the saturation longitudinal force is the driving torque applied to the wheels 10 by the drive/transmission device D when the slip ratio reaches the set value Sa, the braking torque applied by the braking device B, or the like. It can be obtained based on the operating state of the motor 12, the operating state of the hydraulic control actuator 46, and the like.

As shown in FIGS. 4(a) and 4(b), as the braking torque applied to the wheels 10 by the braking device B and the braking torque applied to the wheels 10 by the drive/transmission device D increase, the wheels 10 and the road surface The front-rear force (frictional force) acting between increases, and the slip ratio increases. However, when the longitudinal force reaches the maximum frictional force, the longitudinal force does not increase even if the driving torque or the braking torque increases, and the slip ratio reaches the set value Sa.
Further, as described above, the driving torque or braking torque is substantially proportional to the longitudinal force (frictional force) until the longitudinal force (frictional force) reaches the maximum frictional force. Therefore, the longitudinal force (frictional force) can be obtained based on the driving torque and the braking torque, that is, the operating state of the engine 11 and the electric motor 12, the operating state of the hydraulic pressure control actuator 46, and the like. However, after the longitudinal force reaches the saturated longitudinal force, it is difficult to estimate the frictional force based on the driving torque and the braking torque.

Therefore, in this embodiment, when the slip ratio reaches the set value Sa, the maximum frictional force, which is the saturated longitudinal force, is acquired based on the state of the drive/transmission device D and the braking device B, and the road μ is acquired. I made it so that it would be done.

Further, the slip rate Sij can be expressed by the following formula when the running speed of the vehicle is vs and the wheel speed (peripheral speed) is vw.
Sij=(vs-vwij)/vs
In the above equation, the braking slip rate is expressed as a positive value and the drive slip rate is expressed as a negative value. Also, the running speed vs of the vehicle V can be obtained based on the maximum value of the detection values of the four front, rear, left, and right wheel speed sensors 90FL, 90FR, 90RL, and 90RR.

In this embodiment, the road surface μ is obtained by executing a road surface μ obtaining program shown in the flowchart of FIG.
In step 1 (hereinafter abbreviated as S1; the same applies to other steps), the running speed vs of the vehicle V is acquired based on the detection value of the wheel speed sensor 90, and the running speed vs and each wheel 10 A slip rate Sij (i=F, R, j=L, R) as a slip state is acquired for each wheel 10 based on the wheel speed vwij. At S2, it is determined whether or not the absolute value of the slip ratio Sij is greater than or equal to the set value Sa.

If the determination in S2 is YES, in S3 it is determined whether or not the absolute value of the slip ratio Sij was smaller than the set value Sa the previous time. In other words, in S2 and S3, it is determined for the first time whether the absolute value of the slip ratio Sij has become equal to or greater than the set value Sa. If the determinations in S2 and S3 are YES, the longitudinal force applied to the wheels 10 is obtained in S4. The braking force as the longitudinal force is at least one of regenerative braking torque and hydraulic braking torque (specifically, the regenerative braking torque determined by the operating state of the inverter 36M and the pressing device 44 controlled by the hydraulic pressure control actuator 46). and at least one of the hydraulic pressure), and the driving force as the longitudinal force is obtained based on the driving torque (specifically, the operating state of the electric motor 12 based on the control of the inverter 36M, the operating state of the engine 11, etc.). obtained based on In S5, the load N applied to the wheel 10 is acquired. The load N applied to each of the wheels 10 is the known vehicle weight, payload, position where the load (luggage) is loaded, amount of fuel, driver weight, position (driver weight, position is manned traveling (considered in the state), etc. Then, in S6, by dividing the maximum frictional force F, which is the longitudinal force applied to the wheels 10, by the load N applied to the wheels 10, the friction coefficient μ is obtained.
μ = F/N

The road surface μ can be obtained by dividing the detection value α of the G sensor 94 at the time when the absolute value of the slip ratio Sij becomes larger than the set value Sa by the gravitational acceleration g. M is the mass of the vehicle V;
α=F/M
μ=α/g

Further, when obtaining the road surface μ in the turning state of the vehicle V, the lateral force acting on the vehicle V (which can be obtained based on the detection value of the G sensor 94, etc.) is obtained, and the lateral force and the longitudinal force are obtained. is obtained as the maximum frictional force, and the road μ can be obtained.
(Longitudinal force) ² + (Lateral force) ² = (Maximum frictional force) ²

The vehicle information creation unit 88 creates vehicle information including road surface μ information as road surface condition information, identification information, and vehicle position information as mobile body position information acquired based on signals received via the GPS receiver 104. It is something to do. The created vehicle information is supplied to the vehicle communication device 108 and transmitted by the vehicle communication device 108 .

A vehicle information creation program represented by the flowchart in FIG. 6 is executed in the vehicle information creation unit 88 .
In S11, road surface μ information is acquired, and in S12, wheel position information (e.g., corresponding to FR, etc.) representing the position of the wheel 10 where the absolute value of the slip ratio Sij is equal to or greater than the set value Sa is acquired. Then, in S13, vehicle position information is obtained. Also, in S14, the identification information ID is read. Then, in S15, vehicle information including identification information, vehicle position information, road surface μ, wheel position information, etc. is created, and the vehicle information is supplied to the vehicle communication device 108 in S16. Vehicle communication device 108 transmits vehicle information.

On the other hand, as shown in FIG. 3, the central control device C includes a central control ECU 150 mainly composed of a computer, a central communication device 152, a map information storage unit 154, and the like. The central control ECU 150 includes a travel command generation unit 156 as a movement command generation unit, a map information generation unit 158, a work plan storage unit 160 as an example of a movement plan information storage unit, and the like.
The travel command creation unit 156 creates a travel command as a move command to the vehicle V based on the vehicle information received by the central communication device 152 .

For example, the vehicle that transmitted the vehicle information (eg, the first vehicle V1 as the first moving body; see FIG. 1) is determined from the identification information (eg, ID1) included in the vehicle information. Further, when the road surface μ represented by the road surface μ information included in the vehicle information is smaller than the set μ value, a travel command is generated for the second vehicle V2 as the second moving object following the first vehicle V1. be. A vehicle that follows the first vehicle V1 is a vehicle that is scheduled to travel next on a road surface on which the first vehicle V1 has detected that the road surface μ is smaller than the set μ value.

For the second vehicle V2, a travel command (brake control command) for controlling the braking torque applied to the wheel 10 at the position determined by the wheel position information included in the vehicle information can be generated.
For example, the braking torque applied to the wheels 10 in the second vehicle V2 can be smaller than the braking torque applied in the first vehicle V1. As described above, the road surface μ is acquired based on the saturation longitudinal force, but it is difficult to accurately acquire the point in time when the absolute value of the slip ratio Sij reaches the set value Sa. Therefore, in the second vehicle V2, the braking torque applied to the wheels 10 is made smaller than the braking torque applied in the first vehicle V1, and the absolute value of the slip ratio Sij reaches the set value Sa for the first time. This is done so that the braking torque can be obtained with high accuracy. As a result, it is possible to accurately acquire the road surface μ of the road surface that is detected to be small by the first vehicle V1.
In contrast, the braking torque applied to the wheels 10 in the second vehicle V2 can be greater than the braking torque applied in the first vehicle V1. This is because the slip state of the wheels 10 can be accurately detected.

Further, in the first vehicle V1, when both the hydraulic braking torque and the regenerative braking torque are applied and the absolute value of the slip ratio Sij becomes equal to or greater than the set value Sa, in the second vehicle V2, the hydraulic A driving command (brake control command) can be generated so that the pressure braking torque is set to 0 and the regenerative braking torque is applied. Regenerative braking torque can be controlled in magnitude more accurately than hydraulic braking torque. Therefore, it is possible to accurately acquire the point in time when the absolute value of the slip ratio Sij becomes equal to or greater than the set value Sa, and the road surface μ can be acquired accurately.

Furthermore, although the vehicle V is often in the four-wheel drive state, a travel command (driving state switching command) for switching to the two-wheel drive state can be generated for the second vehicle V2. In the two-wheel drive state, the drive torque applied to the wheels 10 can be made larger than in the four-wheel drive state, so the slip state can be accurately detected. Further, in the two-wheel drive state, the drive torque applied to the wheels can be obtained more accurately than in the four-wheel drive state, and the road surface μ can be obtained more accurately.

Further, a travel command (route change command) can be generated so that the route of the second vehicle V2 is shifted from the route of the first vehicle V1. A plurality of vehicles V often travel along the same predetermined route. The road surface μ of different parts is acquired. As a result, it is possible to efficiently acquire the road surface condition within the area.

The map information creation unit 158 creates and updates map information by adding road surface μ information to a map representing terrain, roads, etc., in an area based on road surface μ information, vehicle position information, etc. included in vehicle information. . The map information created and updated by the map information creation unit 158 is stored in the map information storage unit 154 .

The work plan storage unit 160 stores work plans for a plurality of vehicles V working within the area. The work plan stores a movement plan (moving route, movement start time, etc.) for each of the plurality of vehicles V, loads (luggage) to be loaded on each of the plurality of vehicles V, and the like. These are often stored based on identification information of each of a plurality of vehicles V. FIG.

In the central control ECU 150, the central control information creation program shown in the flowchart of FIG. 8 is executed at predetermined set time intervals.
At S31, it is determined whether or not vehicle information has been received in the central communication device 152 . If received, road surface μ information and vehicle position information are acquired from the vehicle information in S32 and S33, and map information is created and updated in S34. The created map information is stored in the map information storage unit 154 .

Next, in S35, it is determined whether or not the road surface μ is smaller than the set μ value. When the determination is YES, in S36, the identification information (ID1) is acquired, and the vehicle (first vehicle V1) that transmitted the vehicle information is specified. In S37, the second vehicle V2 that follows the first vehicle V1 is specified based on the work plan stored in the work plan storage unit 160, and the identification information ID2 of the second vehicle V2 is acquired. Further, when specifying the first vehicle V1 and the second vehicle V2, it is desirable to consider the vehicle position information included in the vehicle information transmitted from the first vehicle V1. At S38, a travel command for the second vehicle V2 is created.

Then, in S39, central control information including the created travel command, the identification information ID2 of the second vehicle V2, etc. is created and supplied to the central communication device 152 in S40. The central communication device 152 transmits central control information.

In each of the plurality of vehicles V, the travel control unit 86 executes a remote control program as a travel control program shown in FIG. 7 at predetermined set time intervals.
In S51, it is determined whether or not central control information has been received by the vehicle communication device 108, and in S52, it is determined whether or not the identification information included in the central control information matches the identification information representing itself. If the determinations in S51 and S52 are YES, it is determined in S53 whether or not the travel command included in the central control information is a route change command. At S55, it is determined whether or not there is a braking control command.

If the determination in S53 is YES, in S56 the steering device ST and the like are controlled so that the vehicle V travels along the route according to the route change command. If the determination in S54 is YES, in S57 the transfer 26 and the like are controlled to switch to the two-wheel drive state.

If the determination in S55 is YES, it is determined in S58 whether or not wheel position information is included, and in S59 it is determined whether or not a regenerative braking switching command is included.
If the determination in S58 is YES, in S60, the hydraulic pressure control actuator 46 controls the pressing force of the hydraulic brake 40 of the wheel 10 at the position represented by the wheel position information.

If the determination in S59 is YES, in S61 the absolute value of the slip ratio Sij is set to be equal to or greater than the set value Sa in consideration of the maximum regenerative braking torque that can be output when the hydraulic braking torque is set to 0. It is determined whether there is a possibility of becoming (denoted as lock prediction in FIG. 7). This is because when the hydraulic braking torque is set to 0, the braking torque applied to the wheels 10 by the braking device B becomes small, and the braking force between the wheels 10 and the road surface may not reach the maximum frictional force. If the determination is YES, in S62 the hydraulic braking torque is controlled to 0 and only the regenerative braking torque is applied.

For example, when the remote control program is executed in the second vehicle V2, the identification information ID2 included in the central control information matches the identification information representing itself. Therefore, the determination in S52 is YES. One or more of the driving/transmitting device D, the braking device B, and the steering device ST of the second vehicle V2 is controlled based on the travel command transmitted from the central control device C by executing S53 and thereafter. Thus, the running state of the second vehicle V2 is controlled.

Then, the road surface μ information is acquired by the second vehicle V2, and vehicle information including the road surface μ information is created and transmitted. The central control device C receives the vehicle information transmitted from the second vehicle V2 and acquires the road surface μ information. For example, the road surface μ acquired by the second vehicle V2 is considered to be more accurate than the value acquired by the first vehicle V1. Therefore, based on the road surface μ acquired by the second vehicle V2, map information can be acquired satisfactorily. Further, when the second vehicle V2 acquires the road surface μ state of a portion different from the portion where the road surface μ is acquired by the first vehicle V1, the map information can be efficiently acquired.

As described above, in this embodiment, the running state of the second vehicle V2 is controlled based on the road surface state detected by the first vehicle V1, which is the vehicle that transmitted the vehicle information. As a result, it is possible to improve the accuracy of the road surface μ, such as correcting the road surface μ acquired by the first vehicle V1 to the road surface μ acquired by the second vehicle V2. Since the first vehicle V1 and the second vehicle V2 are vehicles of the same type and the same type, variations in vehicle characteristics are small. Therefore, the road surface μ acquired by the first vehicle V1 and the road surface μ acquired by the second vehicle V2 can be considered to be acquired by the same vehicle, and the accuracy of the acquired road surface μ state can be improved. can be done.

In addition, in order to improve the accuracy of the road surface μ information, it is possible for the same vehicle to travel on the same route a plurality of times. Moreover, it can be acquired from efficiency.

Furthermore, since the second vehicle V2 acquires the road surface μ information of the portion of the road surface that is not acquired by the first vehicle V1, it is possible to efficiently acquire the road surface μ in the area.

Further, the central control ECU 150 can create a travel command for at least one of the plurality of vehicles V based on the updated map information. For example, when the third vehicle V3 (see FIG. 1) among the plurality of vehicles is traveling toward a portion where the road surface μ is smaller than the set μ value, the third vehicle V3 is instructed to change the traveling route. You can create a command or you can create a slowdown command to slow down.

An example of such a case is represented by the flow chart of FIG.
In S71, the map information is read, and in S72, it is determined whether or not there is a vehicle (for example, the third vehicle V3) that is traveling toward a portion of the road surface μ that is small among the plurality of vehicles V. If the determination is YES, the identification information ID3 of the third vehicle V3 is acquired in S73, and a travel command to the third vehicle V3 is created in S74. In S75, central control information including the identification information ID3 of the third vehicle V3 and the travel command is created, and the central control information is supplied to the central communication device 152 in S76.

In this embodiment, since the map information is acquired with high accuracy, appropriate travel commands can be supplied to a plurality of vehicles V. FIG. It is possible to improve the running performance of each of the plurality of vehicles V, and to make it difficult for the vehicle to get stuck. As a result, working efficiency can be improved.

As described above, in this embodiment, the in-region road surface condition obtaining section and the map information preparing section are configured by the section for storing and executing S31 to S34 of the central control information preparation program of the central control ECU 150 . Further, the road surface condition acquisition unit 84 is a related condition acquisition unit such as road surface μ, and a road surface μ acquisition unit. A management system is configured by the central control ECU 150, the central communication device 152, and the like. Also, identification information, vehicle position information, or the like is an example of the mobile body position specifying information.

In the above embodiment, the case where the vehicle V is in the automatic driving state has been described, but the present invention can also be implemented in the case where the vehicle V is in the manual driving state.
In this embodiment, the central control device C creates and transmits a driving command as a driving command. In each of the plurality of vehicles V, the driving command is notified to the driver via the notification device 106 . When the vehicle V is a manual driving vehicle or a vehicle capable of switching between a manual driving state and an automatic driving state, a steering operation member, a brake operation member, and a switch capable of switching between a four-wheel drive state and a two-wheel drive state are used. A certain driving state changeover switch or the like is usually provided. Therefore, a command to operate the steering operation member, a command to loosen the operation state of the brake operation member, a command to operate the drive state changeover switch, and the like are generated and transmitted as the operation command. The driver drives the vehicle V according to the driving command supplied via the notification device 106 .

Further, for example, it is also possible to perform driving assistance such as providing operation assistance to encourage operation of the steering operation member in one direction (for example, applying force in one direction to the operation operation member) based on the driving command. be.

Further, the vehicle information can include slip ratio information representing the slip ratio of the wheels 10 . As a result, it is possible for the central control device C to clearly acquire that the slip ratio of the wheels 10 has increased and that the road surface μ has changed from a low road surface μ state to a high road surface μ state.
For example, the slip ratio is smaller than the set value Sa in a state in which a torque greater than or equal to the torque applied by the drive/transmission device D or the braking device B when the previous slip ratio was equal to or greater than the set value Sa is applied to the wheels 10. In this case, it can be estimated that the road surface μ has changed to a high road surface.

Further, the road surface μ related state can be acquired based on the detection value of the yaw rate sensor 92 . An example of this is represented by a road surface μ-related state acquisition program represented by the flow chart of FIG.
In S91, the actual yaw rate detected by the yaw rate sensor 92 is read, and in S92, the steering angle of the steering device ST (the rotation angle of the steering actuator 60) and the travel speed vs of the vehicle V are acquired. A target yaw rate γa is acquired based on the above. Then, in S93, it is determined whether or not the actual yaw rate γ is within the set range determined by the target yaw rate γa. If the determination is YES, it is acquired in S94 that the road surface μ is in a high state, and if it is NO, in S95 it is acquired that the road surface μ is in a low state.

Thus, in this embodiment, vehicle information including road surface μ related information indicating whether the road surface μ is in a low state or a high state is transmitted. Therefore, it is possible for the central control device C to acquire whether the road surface μ is low or high.

Also, in the above embodiment, the case where the plurality of vehicles V are hybrid vehicles has been described, but the present invention is not limited to this. For example, it can be an electric vehicle as shown in FIG.
The vehicle shown in FIG. 11 includes an electric motor 172F for driving the front wheels and an electric motor 172R for driving the rear wheels. On the front wheel side, the electric motor 172F is connected to a differential device 178F via a transmission 176F, and the differential device 178F is connected to drive shafts 24FL and 24FR, respectively, to drive the left and right front wheels 10FL and 10FR. Connected. The same is true for the rear wheel side. Differential 178 may include, for example, a differential gear mechanism.

Also, the electric motors 172F and 172R are connected to a common battery 184 via inverters 182F and 182R, respectively. Under the control of the inverters 182F and 182R, the electric power of the battery 184 is supplied to the electric motor 172, and the electric power generated by the electric motor 172 is charged to the battery 184 to generate regenerative braking force. can be switched to In other words, the wheels 10 receive the output of the electric motor 172 and the regenerative braking force via the transmission 176, the differential 178, and the drive shaft, respectively.

In this embodiment, the four-wheel drive state is established when the electric motors 172F and 172R are in the driving state, and the two-wheel drive state is established when one of the electric motors 172F and 172R is in the free state.

In addition, the vehicle V may be a vehicle that does not include an electric motor as a drive source, an electric vehicle that does not include an engine as a drive source, a fuel cell vehicle, or the like. Also, an in-wheel motor can be provided for each wheel 10 as a drive source. Further, each of the steerable wheels 10 can be provided with a steering device capable of being steered independently. Further, the structure of the vehicle V is not limited, for example, an electric brake can be included as the friction braking device.

In the above embodiment, the road surface μ and the road surface μ-related condition are acquired as the road surface condition, but it is also possible to acquire the unevenness of the road surface as the road surface condition.

In addition, the present invention can be implemented in various aspects with various modifications and improvements based on the knowledge of those skilled in the art.

10: Wheel 11: Engine 12: Electric Motor 26: Transfer 36: Inverter 38: Battery 40: Hydraulic Brake 41: Hydraulic Braking Device 46: Hydraulic Control Actuator 60: Steering Actuator 80: Vehicle ECU 82: Identification Information etc. Storage unit 84: Road surface condition acquisition unit 86: Travel control unit 88: Vehicle information creation unit 90: Wheel speed sensor 108: Vehicle communication device 150: Central control ECU 152: Central communication device 154: Map information storage unit 156: Travel command creation Unit 158: Map information update unit B: Braking device D: Drive/transmission device ST: Steering device

Patentable Inventions

The following paragraphs describe a claimable invention.
(1) A road surface condition acquisition system including a central control unit that acquires a road surface condition, which is the condition of a road surface in an area where the plurality of mobile bodies move, by communicating with each of the plurality of mobile bodies,
Each of the plurality of moving bodies, respectively,
(i) a moving body road surface condition acquisition unit that acquires the road surface condition of the road surface on which the moving object is moving;
(ii) a mobile communication device that transmits at least mobile information including mobile road surface condition information representing the road surface condition acquired by the mobile object road surface condition acquiring unit;
The central control device
(a) a central communication device for receiving said mobile information;
(b) a movement command creation unit that creates a movement command, which is a command relating to movement of at least one of the plurality of mobile bodies, based on the mobile body information received by the central communication device;
The central communication device transmits central control information including the movement command created by the movement command creation unit,
A road surface condition acquisition system in which the central control device includes an in-region road surface condition acquisition unit that acquires the road surface condition within the region based on the mobile object information received by the central communication device.

The road surface condition can be, for example, the unevenness of the road surface, or the road surface μ-related condition related to the road surface μ. The road surface μ-related state can be represented by the road surface μ, or whether the road surface μ is small or large (whether the road surface is a low μ road or a high μ road).

When the mobile body is in a state capable of automatic operation and remote control is possible based on a command from the central control system, the movement command is a command of the running state of the mobile body (driving device, braking device, steering (including instructions to the device). If the vehicle is in manual operation and is not remotely controllable, the movement commands may represent driving (operation) commands to the driver.

Even if the mobile communication device transmits mobile body information at set time intervals while the device is running, it may not be possible to move when the unevenness of the road surface is greater than or equal to the set state, or when the coefficient of friction of the road surface is acquired. Body information may be transmitted.

The region in which a plurality of moving bodies move can be, for example, a region in which a plurality of moving bodies work. When a plurality of moving bodies work in a mine, it means the work area of the mine.

(2) the mobile body information includes mobile body position specifying information that is information that can specify the position to which the mobile body moves;
The in-region road surface condition acquisition unit
a map information creation unit for creating map information representing a road surface condition in the area based on the mobile object road surface condition information and the mobile object position specifying information included in the mobile object information received by the central communication device; ,
The road surface condition acquisition system according to item (1), further comprising a map information storage unit that stores the map information created by the map information creation unit.

The moving object position specifying information is information representing the position of the moving object, that is, information representing the two-dimensional position (latitude, longitude) where the moving object exists, or information representing the three-dimensional position (latitude, longitude, altitude). However, it may be identification information or the like that can identify the position of the moving object. For example, when the central control unit stores movement plan information (moving route, movement time, etc.) for each of a plurality of moving bodies, the position of the moving body can be determined if the identification information for specifying the moving body is known. I understand.

(3) The moving object road surface condition acquiring unit acquires a road surface μ, which is a coefficient of friction of the road surface, or a condition related to the road surface μ as the condition of the road surface on which the moving object moves. including
Road surface condition acquisition according to item (1) or item (2), wherein the road surface condition information of the moving body includes related information such as road surface μ, which is information representing the road surface μ or information representing a condition related to the road surface μ. system.

Based on the road surface μ, the state of the slipperiness of the road surface can be known. The state related to the road surface friction coefficient corresponds to a state in which the road surface friction coefficient is low, a state in which the road friction coefficient is high, and the like.

(4) the plurality of moving bodies, each of which includes a plurality of wheel speed sensors that respectively detect the rotation speed of each of a plurality of wheels provided on the moving bodies; and an acceleration sensor that detects the acceleration of the moving bodies; a yaw rate sensor that detects the yaw rate of the moving body;
The related state acquisition unit for road surface μ, etc., based on at least one or more of a plurality of detected values of the plurality of wheel speed sensors, a detected value of the acceleration sensor, and a detected value of the yaw rate sensor, The road surface condition acquisition system according to item (3), which acquires the road surface μ or a condition related to the road surface μ.

For example, when the detected value of the yaw rate sensor is out of the set range determined by the target yaw rate determined based on the steering angle and the moving speed, it is acquired that the road surface μ is in a low state (road surface μ related state). be able to.

The road surface μ related state includes road surface μ and road surface μ related state, and the road surface μ related information includes road surface μ information and road surface μ related information.

(5) The road surface μ related state acquisition unit detects that the slip state of at least one of the plurality of wheels has reached a set state or higher based on the detection values of the plurality of wheel speed sensors. The road surface condition acquisition system according to item (4), including a road surface μ acquisition unit that acquires the road surface μ with which the at least one wheel is in contact when the vehicle is in contact with the road surface μ.

When the slip state exceeds the set state, it can be considered that the longitudinal force (driving force or braking force) acting between the wheels and the road surface has reached the maximum frictional force. Therefore, in this case, the longitudinal force (maximum frictional force) acting between the wheel and the road surface is acquired based on the driving torque and braking torque applied to the wheel from the vehicle's driving / transmission device and braking device, and this maximum The road surface μ is obtained based on the friction force and the load acting on the wheel.

(6) each of the plurality of mobile bodies includes a storage unit that stores the weight of a load loaded on the mobile body;
any one of the items (5), wherein the road surface μ acquisition unit acquires the road surface μ using a moving body weight acquired based on the weight of the load stored in the storage unit. The road surface condition acquisition system described.

Each mobile object is managed by identification information. A driver and a load are stored in association with the identification information of the moving body, and based on these, the weight of the entire moving body is obtained. Also, if the load and the position of the driver are known, the load applied to each wheel can also be known.
The storage unit described in this item corresponds to the storage unit for identification information, etc. in the above embodiment.

In addition, when the load, the weight of the driver, their positions, etc. are stored in the central control device, the information such as the load is transmitted to the plurality of mobile bodies through communication between the central control device and the plurality of mobile bodies. can be obtained so that the road surface μ is obtained.

(7) the mobile body information includes identification information identifying each of the plurality of mobile bodies;
The central control device includes a movement plan information storage unit that stores movement plan information that is information about the movement plan of each of the plurality of mobile bodies,
The mobile body for which the movement command generation unit has transmitted the mobile body information among the plurality of mobile bodies based on the identification information and the movement plan information included in the mobile body information received by the central communication device (1) to (6) specifying the first moving body that is the ), the road surface condition acquisition system according to any one of the items.

The central control unit stores data relating to movement plans (work plans) representing planned movement routes of a plurality of moving bodies. Therefore, based on the work plan of a plurality of moving bodies and the identification information of the first moving body, it is possible to specify the identification information of the second moving body, which is a moving body following the first moving body.

(8) The road surface condition acquisition system according to item (7), wherein the movement command creation unit creates a command for the second moving body to travel on a route different from that of the first moving body.

In order to acquire the road surface condition of a portion of the road surface different from the portion in contact with the wheels of the first moving body, a movement command is created so as to change the path of the second moving body from the path of the first moving body. The road surface condition of a portion of the road surface different from that of the first moving object is acquired by the moving object road surface condition acquiring unit of the second moving object.

(9) the moving object road surface condition acquisition unit includes a road surface μ acquisition unit that acquires a road surface μ that is a friction coefficient of the road surface as the condition of the road surface on which the moving object moves;
the mobile road surface state information includes information representing the road surface μ;
each of the plurality of mobile bodies includes a drive/transmission device capable of switching between a four-wheel drive state and a two-wheel drive state;
When the road surface μ represented by the road surface μ information included in the mobile unit information transmitted from the first mobile unit and received by the central communication device is smaller than the set μ value, the movement command generation unit determines the second The road surface condition acquisition system according to item (7) or item (8), wherein a command for switching from the four-wheel drive state to the two-wheel drive state is created for the moving object.

By setting the vehicle to the two-wheel drive state, it is possible to accurately obtain the driving force, which is the longitudinal force applied to the wheels, and to accurately obtain the coefficient of friction of the road surface.

(10) each of the plurality of moving bodies includes a plurality of wheel speed sensors that respectively detect rotational speeds of a plurality of wheels provided on the moving body;
When the moving body road surface condition acquisition unit detects that the slip state of at least one of the plurality of wheels has reached a set state or higher based on the detection values of the plurality of wheel speed sensors, including a road surface μ acquisition unit that acquires the friction coefficient of the road surface with which the at least one wheel is in contact,
the mobile road surface state information includes information representing the road surface μ;
The mobile object information includes wheel position information representing the position of at least one of the plurality of wheels at which the slip state is set,
(7) to (9), wherein the movement command creation unit creates a command to reduce the torque applied by the second moving body to the wheels of the second moving body at positions determined by the wheel position information; ), the road surface condition acquisition system according to any one of the items.

The torque may be driving torque or braking torque. However, if the driving torque cannot be controlled for each wheel, the technical feature according to this section is applied when the road surface μ is obtained with the braking torque applied.
Further, the torque applied to the wheels by the second moving body means the torque applied to the wheels by the driving/transmitting device and the braking device included in the second moving body.

(11) Each of the plurality of moving bodies includes a friction braking device that applies friction braking torque to each of the plurality of wheels, and a regenerative braking device that applies regenerative braking torque to a driving wheel of the plurality of wheels. and
The moving body road surface state acquisition unit includes a road surface μ acquisition unit that acquires a road surface μ that is a friction coefficient of the road surface as the state of the road surface on which the moving body moves,
When the road surface μ represented by the road surface μ information included in the mobile unit information transmitted from the first mobile unit and received by the central communication device is smaller than the set μ value, the movement command generation unit determines the second The road surface according to any one of items (7) to (10), wherein a command is created for the moving body to apply the regenerative braking torque to the drive wheels and not apply the friction braking torque. status acquisition system.

(12) If the torque applied to the wheel is equal to or greater than the torque applied to the wheel when the road surface μ was acquired last time, the road surface μ related state acquisition unit determines whether the at least one wheel The road surface condition acquisition system according to item (3), which acquires that the road surface is a high μ road when the slip condition is smaller than the set condition.

For example, it is possible to effectively notify the central control unit that the friction coefficient of the road surface has changed from a low state to a high state.

(13) Each of the plurality of moving bodies is in an automatic driving state in which the running state can be controlled based on a command from the central control device, and the running state of the moving body conforms to the command from the central control device. The road surface condition acquisition system according to any one of items (1) to (12), which is remotely controllable based on.

(14) The move command creation unit creates a move command for at least one of the plurality of moving bodies based on the map information stored in the map information storage unit. The road surface condition acquisition system described in the item.

For example, when the road surface μ at a position P represented by the map information is low, a command is generated for the moving object that is scheduled to run at that position P to avoid the position P and to run or to reduce the speed. You can do, etc.

(15) A management system including a central control device that manages a plurality of mobile bodies by communicating with the plurality of mobile bodies,
Each of the plurality of moving bodies, respectively,
(i) a road surface condition acquisition unit that acquires the road surface condition of the road surface on which the moving body is running;
(ii) Transmitting mobile object information including at least road surface condition information representing the condition of the road surface acquired by the road surface condition acquiring unit and mobile object position information representing a position on which the mobile object travels; a mobile communication device that
The central control device
(a) a central communication device for receiving said mobile information;
(b) a map information updating unit that updates map information based on the mobile information received by the central communication device;
(c) a map information storage unit that stores the map information updated by the map information update unit; A management system that creates movement orders for one.
The management system described in this section can adopt the technical features described in any of items (1) to (13).

Claims (3)

A road surface condition acquisition system including a central control unit that acquires a road surface condition, which is the condition of a road surface in an area where the plurality of mobile bodies move, by communicating with each of the plurality of mobile bodies,
Each of the plurality of moving bodies, respectively,
(i) a moving body road surface condition acquisition unit that acquires the road surface condition of the road surface on which the moving object is moving;
(ii) a mobile communication device that transmits at least mobile information including mobile road surface condition information representing the road surface condition acquired by the mobile object road surface condition acquiring unit;
The central control device
(a) a central communication device for receiving said mobile information;
(b) a movement command creation unit that creates a movement command, which is a command relating to movement of at least one of the plurality of mobile bodies, based on the mobile body information received by the central communication device;
The central communication device transmits central control information including the movement command created by the movement command creation unit,
A road surface condition acquisition system in which the central control device includes an in-region road surface condition acquisition unit that acquires the road surface condition within the region based on the mobile object information received by the central communication device. the mobile information includes identification information identifying each of the plurality of mobiles;
The central control device includes a movement plan information storage unit that stores movement plan information that is information about the movement plan of each of the plurality of mobile bodies,
A movement in which the movement command creation unit transmits the mobile body information among the plurality of mobile bodies based on the identification information and the movement plan information included in the mobile body information received by the central communication device 2. The road surface according to claim 1, wherein a first moving body is specified, a second moving body following the first moving body is specified, and a command relating to movement of the second moving body is created. status acquisition system. the mobile body information includes mobile body position specifying information that is information that can specify the position to which the mobile body moves;
The in-region road surface condition acquisition unit
a map information creation unit for creating map information representing a road surface condition in the area based on the mobile object road surface condition information and the mobile object position specifying information included in the mobile object information received by the central communication device; ,
a map information storage unit that stores the map information created by the map information creation unit;
3. The movement command creation unit creates the movement command for at least one of the plurality of moving bodies based on the map information stored in the map information storage unit. The road surface condition acquisition system described in .

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