Utility Vehicles

Abstract

A multi-purpose vehicle comprises: a travel device including front wheels and rear wheels, a steering device provided on the front wheels and a driving source for driving the front wheels and / or the rear wheels; a control device that controls the travel device in the form of automatic travel without human operation in a specified travel area; and a vehicle position detection unit that detects the position of the vehicle; the control device controls the travel device as follows during automatic travel: based on road condition data that divides the travel area into a plurality of predetermined road condition levels, it is determined to which of the plurality of road condition levels the road condition ahead of the vehicle's position in the direction of travel belongs, so that the specified travel parameters correspond to the plurality of road condition levels respectively and are within a pre-set allowable range.

Description

Technical Field

[0001] The present disclosure relates to utility vehicles. Background Art

[0002] A utility vehicle that can travel on rough terrain is used, for example, for transporting crops, etc., monitoring work in a field, etc. It is assumed that such work is performed repeatedly and regularly while traveling on a predetermined travel route.

[0003] In recent years, various technologies for autonomous driving in automobiles have been proposed. For example, the following patent document 1 discloses a system for an autonomous vehicle to travel on a predetermined driving route. According to this, human operation is not required during driving on the predetermined driving route.

[0004] Prior art literature:

[0005] Patent Literature:

[0006] Patent document 1: Japanese Patent Application Publication No. 2020-13379. Summary of the invention

[0007] Problems to be solved by the invention:

[0008] In such existing autonomous driving vehicles, driving on rough terrain is not envisioned. For example, in existing autonomous driving vehicles, when it is determined that there is an obstacle ahead, control is performed to avoid it or stop the vehicle. However, a multi-purpose vehicle driving on rough terrain can overcome some obstacles and drive. Therefore, the autonomous driving of a multi-purpose vehicle driving on rough terrain requires different control from that of an existing autonomous driving vehicle moving on flat ground.

[0009] Therefore, an object of the present disclosure is to provide a utility vehicle capable of performing appropriate automatic driving control in a utility vehicle that can travel on rough terrain.

[0010] Means of solving the problem:

[0011] According to one form of the multi-purpose vehicle disclosed in the present invention, there is provided: a driving device including front wheels and rear wheels, a steering device provided on the front wheels and a driving source for driving the front wheels and / or the rear wheels; a control device that controls the driving device in the form of automatic driving without human operation in a specified driving area; and a vehicle position detection unit that detects the position of the vehicle; the control device controls the driving device as follows during the automatic driving: based on road condition data that divides the driving area into a plurality of predetermined road condition levels, it is determined to which of the plurality of road condition levels the road condition ahead of the vehicle's position in the direction of travel belongs, so that the specified driving parameters correspond to the plurality of road condition levels respectively and are within a pre-set allowable range.

[0012] Effect of the invention:

[0013] According to the present disclosure, when a multi-purpose vehicle is automatically traveling, different driving devices are controlled according to the road condition level ahead of the vehicle's position in the traveling direction. Therefore, in a place with a poor road condition, such as low-speed driving, the driving control of the automatic driving can be changed from the control in a place with a good road condition. Therefore, in a multi-purpose vehicle that can travel on rough terrain, appropriate automatic driving control corresponding to the road condition can be performed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic left side view showing a utility vehicle according to one embodiment;

[0015] Figure 2 It is shown Figure 1 A schematic block diagram of a control system of a utility vehicle is shown;

[0016] Figure 3 is a plan view showing an example of a travel area of ​​a utility vehicle according to the present embodiment;

[0017] Figure 4 This is a flowchart for illustrating the flow of processing of driving control according to the road surface condition in the automatic driving mode of the present embodiment. DETAILED DESCRIPTION

[0018] In the following, the embodiments are described with reference to the accompanying drawings. In the entire drawings, the same or corresponding elements are denoted by the same reference numerals and repeated descriptions are omitted.

[0019] (Structure of the vehicle)

[0020] Figure 1 It is a schematic left side view showing a utility vehicle according to an embodiment. Figure 1 The utility vehicle 1 (hereinafter referred to as the vehicle 1 ) shown includes a pair of left and right front wheels 2 and a pair of left and right rear wheels 3. The front wheels 2 and the rear wheels 3 support a vehicle body frame 4. The vehicle body frame 4 is a pipe frame formed by connecting a plurality of pipes to each other.

[0021] The vehicle body frame 4 supports the front seat 5A and the rear seat 5B. The front seat 5A includes a driver's seat. In addition, the seats are not limited to two rows, and one row is also possible. The vehicle body frame 4 is configured to surround the passenger space C including the front seat 5A and the rear seat 5B. That is, the passenger space C is divided by the vehicle body frame 4. The engine hood 6 is arranged in front of the passenger space C (front seat 5A). The engine hood 6 is supported on the front part of the vehicle body frame 4, and can be opened and closed from above to cover the space between the left and right front wheels 2.

[0022] A front side door 7A is provided on the side of the front seat 5A, and a rear side door 7B is provided on the side of the rear seat 5B. These side doors 7A and 7B are supported by the vehicle body frame 4. Each side door 7A and 7B rotates around a rotation axis provided at the front end relative to the vehicle body frame 4 to open and close. In this way, passengers can get on and off the vehicle 1. In addition, Figure 1 The center side doors 7A and 7B are shown in a form in which the inner side (passenger space C side) thereof is seen through.

[0023] A loading platform 8 is arranged behind the passenger space C (rear seat 5B). The loading platform 8 is supported by the rear portion of the vehicle body frame 4. A driving source 9 supported by the vehicle body frame 4 is arranged below the loading platform 8. The driving source 9 is, for example, an engine. Alternatively, the driving source 9 may be an electric motor or a combination of an engine and an electric motor. The driving source 9 drives the driving wheels (the front wheels 2 and / or the rear wheels 3).

[0024] A first operating member 10 including an accelerator pedal and a brake pedal is provided in front of and below the driver's seat (in the driver's foot area). The accelerator pedal is operated to change the driving force of the driving source 9. A brake device (not shown) is provided on the front wheels 2 and the rear wheels 3, and the brake pedal is operated to decelerate the vehicle 1. In this way, the first operating member 10 is configured as an operating member for accelerating and decelerating the vehicle 1.

[0025] A steering device 11 is provided on the front wheel 2. In addition, a handle 12 is provided in front of the driver's seat in the front seat 5A as a second operating member. The handle 12 is connected to the steering device 11, and the steering device 11 is operated according to the operation of the handle 12, so that the front wheel 2 is turned. In this way, the second operating member is configured as an operating member for changing the direction of the vehicle 1.

[0026] The vehicle 1 also includes a transmission (not shown) connecting the drive source 9 and the drive wheels. The transmission changes the speed ratio or the travel direction (forward or reverse) based on the operation of a third operating element such as a shift lever (not shown).

[0027] As described above, the travel device 14 for driving the vehicle 1 includes the front wheels 2, the rear wheels 3, the steering device 11, the drive source 9, the brake device, the transmission device, etc. The operating member for operating the travel device 14 includes the first operating member, the second operating member, and the third operating member.

[0028] In addition, the vehicle 1 includes a control device 13 for controlling the travel device 14. The control device 13 is connected to various sensors described later. The control device 13 obtains detection values ​​of various sensors. The control device 13 includes a processor, a volatile memory, a nonvolatile memory (memory), an I / O interface, etc., and is configured as an electronic circuit that realizes various controls by using a volatile memory to perform calculations based on a program stored in the nonvolatile memory.

[0029] (Structure of control system)

[0030] Figure 2 It is shown Figure 1 A schematic block diagram of a control system of a utility vehicle is shown in FIG. Figure 2 As shown, the control device 13 is connected to various sensors. The sensors detect the vehicle state of the travel system including the operating elements and the travel device 14.

[0031] The sensors include, for example, an accelerator opening sensor 15, a brake amount sensor 16, a steering angle sensor 17, a drive source rotation speed sensor 18, a vehicle speed sensor 19, a wheel rotation speed sensor 20, a suspension stroke sensor 21, a pitch angle sensor 22, and a roll angle sensor 23. The vehicle 1 may include all of these sensors, some of these sensors, or sensors other than these sensors.

[0032] The accelerator opening sensor 15 detects the operation amount of the accelerator pedal. The brake amount sensor 16 detects the operation amount of the brake pedal. The steering angle sensor 17 detects the operation direction and operation amount of the handle 12. The drive source rotation speed sensor 18 detects the rotation speed of the output shaft of the drive source 9. The vehicle speed sensor 19 detects the speed of the vehicle 1.

[0033] The wheel speed sensor 20 detects the rotation speed of each wheel 2, 3. The wheel speed sensor 20 may be provided on each of the four wheels (the left and right front wheels 2 and the left and right rear wheels 3). In addition, the vehicle speed may be obtained from the rotation speed of the driving wheel (e.g., the rear wheel 3) instead of the vehicle speed sensor 19. The suspension stroke sensor 21 detects the extension and contraction amount of the suspension (not shown) provided on each of the wheels 2, 3 of the vehicle 1. The suspension stroke sensor 21 may be provided on each of the four suspensions provided on the four wheels.

[0034] The pitch angle sensor 22 detects the rotation angle of the vehicle 1 about the pitch axis (a virtual rotation axis extending in the vehicle width direction) of the vehicle 1. In addition, instead of providing the pitch angle sensor 22, the pitch angle may be detected from the difference in the expansion and contraction amount between the front suspension and the rear suspension detected by the suspension stroke sensor 21. The roll angle sensor 23 detects the rotation angle of the vehicle 1 about the roll axis (a virtual rotation axis extending in the vehicle front-rear direction) of the vehicle 1. In addition, instead of providing the roll angle sensor 23, the roll angle may be detected from the difference in the expansion and contraction amount between the right suspension and the left suspension detected by the suspension stroke sensor 21.

[0035] The control device 13 controls the driving device 14 so that the vehicle can automatically drive without human operation in a predetermined driving area. The control device 13 is connected to the mode switching unit 50. The mode switching unit 50 switches between a human operation mode in which the vehicle drives in accordance with the operation of the operating element by the control device 13 and an automatic driving mode in which the vehicle automatically drives without the operation of the operating element according to a predetermined driving path.

[0036] The mode switching unit 50 transmits a mode switching signal based on the switching of the switch or various authentication operations to the control device 13. The control device 13 switches the control mode between the human operation mode and the automatic driving mode according to the received mode switching signal.

[0037] In the manual operation mode, the control device 13 controls the travel device 14 according to the input of the various operating members operated by the driver. For example, the control device 13 adjusts the output of the driving source 9 according to the accelerator opening, which is detected by the sensor 15 in response to the driver's operation of the accelerator pedal (the control of the throttle opening in the case of the engine, etc.). In addition, for example, the control device 13 adjusts the steering angle of the steering device 11 according to the steering angle and steering direction, which are detected by the steering angle sensor 17 in response to the driver's operation of the handle 12.

[0038] On the other hand, in the automatic driving mode, the control device 13 performs automatic driving according to a predetermined driving route without operating the operating element. For example, the vehicle 1 includes a front space detection unit 29 for detecting the state of the driving space in front of the vehicle 1 and a vehicle position detection unit 30 for detecting the vehicle position.

[0039] The front space detection unit 29 includes, for example, at least one of a camera, various radars, and laser sensors. The control device 13 analyzes the front space based on the image data of the front space captured by the camera and / or the distance data measured by various radars or laser sensors. The control device 13 controls the driving device 14 based on the analysis result of the front space. For example, when there is an obstacle in front, the control device 13 controls the driving source 9 and / or the braking device (not shown) in the form of slowing down or stopping the vehicle 1, or controls the steering device 11 to change the direction of travel of the vehicle 1.

[0040] The vehicle position detection unit 30 includes, for example, a GPS cable. The memory of the control device 13 stores data of a preset driving route. The control device 13 reads the data of the driving route in the automatic driving mode, and controls the driving device 14 to drive along the driving route based on the information of the vehicle position from the vehicle position detection unit 30. In addition, the control device 13 fine-adjusts the driving route based on the above-mentioned analysis result of the front space. For example, when there is an obstacle in front, the control device 13 performs a reroute setting of the driving route.

[0041] The vehicle 1 is provided with a route setting device 41 for setting a driving route for automatic driving. The route setting device 41 may be configured as a control block of the control device 13, or may be configured by another computer. When the route setting device 41 is configured by another computer different from the control device 13, the route setting device 41 may be provided in the vehicle 1, or may be configured by a computer such as a mobile terminal (tablet terminal) that can communicate via a communication network.

[0042] The route setting device 41 is configured to be able to communicate with the outside through a communication network, and is connected to a data receiving unit 42 that receives predetermined data from the outside. The data of the driving route, for example, a user pre-sets and inputs the driving route in a mobile terminal (tablet terminal, etc.) that can communicate with the vehicle 1 through a communication network, and the set input information is sent to the control device 13 of the vehicle 1 through a predetermined server device. Alternatively, an operation terminal connected to the control device 13 for the user to set and input the driving route may be mounted on the vehicle 1.

[0043] According to the above structure, the mode switching unit 50 switches between the manual operation mode for driving in accordance with the operation of the operating member and the automatic driving mode for driving automatically without the operation of the operating member according to the prescribed driving path. Therefore, the automatic driving mode is executed when performing regular work, so that manual operation is not required, which can reduce the workload. In addition, when performing temporary work, the manual operation mode is executed as needed, so that it can be used as a manually operated multi-purpose vehicle 1. Therefore, according to the above structure, in the multi-purpose vehicle 1 that can automatically drive according to the prescribed driving path, it can be flexibly used.

[0044] In addition, in the present embodiment, the vehicle 1 can also be driven in the automatic driving mode so that passengers can enter the passenger space C. That is, the vehicle 1 can be driven in the automatic driving mode with or without passengers.

[0045] (Details of automatic driving mode)

[0046] The automatic driving mode is described in detail below. For example, the user performs a predetermined start operation, and the vehicle 1 starts. The user performs a mode switching operation to the automatic driving mode, and the mode switching unit 50 sends a mode switching signal for switching to the automatic driving mode to the control device 13. Then, the control device 13 causes the path setting device 41 to execute a setting process of the driving path (driving path setting program).

[0047] The setting of the driving route can be performed by reading the driving route stored in the memory in advance. When the driving route is not stored in the memory, or when the vehicle is traveling on a different driving route from the previous one, the driving route can be re-set. In this case, for example, the route can be set by a mobile terminal that can be connected to the vehicle 1 by wireless or wired communication.

[0048] For example, a map is displayed on the mobile terminal, and a route or destination is input on the map. The route setting device 41 executes a driving route setting program to set a driving route based on the input route and destination information, the vehicle position information, and the terrain information pre-stored corresponding to the map. In addition, for example, when the vehicle 1 is used for patrolling in a specified area, the patrol area can be set on the map, and the route setting device 41 can set a driving route for traveling in the entire patrol area. After the driving route is set, the control device 13 starts automatic driving.

[0049] (Driving control according to road conditions)

[0050] During the automatic driving in the automatic driving mode, the control device 13 controls the driving device 14 according to the road surface condition ahead of the vehicle position in the traveling direction. Therefore, the control device 13 obtains the road surface condition data in the driving area. The road surface condition data divides the driving area into a plurality of predetermined road surface condition levels. The road surface condition data is stored in a memory in the vehicle 1 or in a storage device (a server device or a mobile terminal, etc.) outside the vehicle 1 that can communicate via a communication network.

[0051] Figure 3 2 is a plan view showing an example of a travel area of ​​a multi-purpose vehicle according to the present embodiment. Figure 4 This is a flowchart for illustrating the flow of processing of driving control according to the road surface condition in the automatic driving mode of the present embodiment. Figure 3 In the example of FIG. 1 , the vehicle 1 is used to perform a predetermined operation in a work area WA (eg, a material storage area). The vehicle 1 performs, for example, a material transport operation or a monitoring operation (patrol driving) of the work area WA in the work area WA. Figure 3 In the example of , the work area WA is set in advance as the travel area SA of the vehicle 1 .

[0052] For example, the reciprocating path between the first position P1 and the second position P2 in the work area WA (the first path R1 from the first position P1 to the second position P2 and the second path R2 from the second position P2 to the first position P1) can be set as the driving path during automatic driving. For example, the first position P1 is set as the material carrying site to the outside, and the second position P2 is set as the material storage site.

[0053] At this time, the vehicle 1 in the automatic driving mode moves from the first position P1 to the second position P2 and stops. At the second position P2, the material is loaded on the loading platform 8 of the vehicle 1. After the material is loaded, the vehicle 1 moves from the second position P2 to the first position P1 and stops. At the first position P1, the material is loaded and unloaded. To perform such operations, the vehicle 1 in the automatic driving mode repeatedly moves back and forth between the first position P1 and the second position P2.

[0054] For example, as the third position P3 of the work area WA, a route for patrolling and monitoring the work area WA along a predetermined route can be set as a route for automatic driving (third route R3). The third route R3 includes, for example, a meandering section M that reciprocates in the first direction X of the work area WA and moves in the second direction Y when the direction is changed.

[0055] like Figure 3 As shown, the work area WA set as the travel area SA is divided into a plurality of predetermined ( Figure 3 In the example of FIG. 4 , there are four road surface condition levels (Lv1, Lv2-1, Lv2-2, and Lv3). The road surface condition data includes data indicating the road surface condition level at each position in the travel area SA.

[0056] When the control mode is switched to the automatic driving mode, the control device 13 reads the set driving route and road surface condition data from the route setting device 41 (step S1). For example, the road surface condition data is read by sequentially reading the data portion representing the road surface condition of the area ahead in the direction of travel of the vehicle position driving route.

[0057] When the vehicle 1 is in automatic driving, the control device 13 determines from the road condition data which of the multiple road condition levels the road condition ahead of the vehicle position in the traveling direction belongs to (step S2). The control device 13 obtains the vehicle position and the traveling direction (orientation) of the vehicle 1 from the vehicle position detection unit 30, and inquires from the road condition data the road condition level of the area ahead of the vehicle position in the traveling direction of the driving area SA.

[0058] For example, the road condition level is divided into stages according to the tilt angle θ of the vehicle 1 when the vehicle 1 is traveling. The tilt angle of the vehicle may also be set to either a pitch angle or a roll angle. Furthermore, the tilt angle of the vehicle may also be a three-dimensional angle that takes into account both the pitch angle and the roll angle. The first level Lv1 is set to an area where the tilt angle θ is less than the first angle θ1 when the vehicle 1 is traveling. The second level Lv2 is set to an area where the tilt angle θ is greater than the first angle θ1 and smaller than the second angle θ2 greater than the first angle θ1 when the vehicle 1 is traveling. The third level Lv3 is set to an area where the tilt angle θ is greater than the second angle θ2 when the vehicle 1 is traveling.

[0059] The second level Lv2 is further divided into a first sub-level Lv2-1 and a second sub-level Lv2-2. The first sub-level Lv2-1 is set when the vehicle 1 is traveling and the inclination angle θ is greater than the first angle θ1 and less than the second angle θ2. S The second sub-level Lv2-2 is set when the vehicle 1 is traveling and the inclination angle θ is a sub-angle θ. S A region that is greater than and less than the second angle θ2.

[0060] The control device 13 controls the travel device 14 in such a manner that the prescribed travel parameters correspond to the plurality of road surface condition levels and are within a pre-set allowable range (steps S3 to S7). More specifically, the control device 13 determines whether the road surface condition level is the first level Lv1 (step S3). When the control device 13 determines that the road surface condition level is the first level Lv1 (step S3 is yes), the control device 13 performs normal (no restriction) control (step S4).

[0061] When the control device 13 determines that the road surface condition level is not the second level Lv2 (step S3 is No), it determines whether the road surface condition level is the second level Lv2 (step S5). When the control device 13 determines that the road surface condition level is the second level Lv2 (step S5 is Yes), the driving restriction control is performed (step S6). When the control device 13 determines that the road surface condition level is not the second level Lv2 and the road surface condition level is the third level Lv3 (step S5 is No), the control device 13 performs the avoidance entry control (step S7).

[0062] For example, the following example shows a case where the driving parameters include speed and steering angle. In this case, when the road surface condition level is the first level Lv1, the control device 13 controls the driving device 14 without performing speed restrictions and steering angle restrictions based on the road surface condition level. Thus, under the road surface condition where the posture of the vehicle 1 is stable, normal driving control is performed. In addition, in this case, when the vehicle 1 is turning or driving in a predetermined speed limit area, speed restrictions other than the road surface condition level are also allowed.

[0063] When the road surface condition level is the second level Lv2, the control device 13 controls the travel device 14 so that the speed of the vehicle 1 is less than the first reference speed V1. Furthermore, when the road surface condition level is the second sub-level Lv2-2, the control device 13 controls the travel device 14 so that the range of the steering angle is less than the predetermined reference range θ in addition to the above-mentioned speed restriction. In addition, the control device 13 does not restrict the steering angle when the road surface condition level is the first sub-level Lv2-1 or the first level Lv1.

[0064] Thus, the speed is limited in the road conditions where the vehicle 1 passes through a drivable obstacle (rocks or depressions, etc.) or passes on a slope of a certain degree or more. In addition, the steering angle range is limited according to the degree of the obstacle or slope, thereby reducing the possibility of the vehicle 1 overturning due to large steering angle steering in a tilted state when passing an obstacle, etc.

[0065] In this way, when the road condition level is the second level Lv2 where the driving restriction control should be performed, different driving restriction controls are performed according to the multiple sublevels Lv2-1 and Lv2-2 belonging to the second level Lv2. As described above, the different restriction controls may be an increase or decrease in the types (number) of the restricted driving parameters, an increase or decrease in the allowable range of the same driving parameter, or a combination thereof.

[0066] When the road surface condition level is the third level Lv3, the control device 13 controls the travel device 14 in a manner to avoid the vehicle 1 from entering the area. For example, Figure 3 When the vehicle 1 is at position Pa, the control device 13 determines the road condition level of the area Aa ahead of the vehicle 1 in the traveling direction. The road condition level of the area Aa is the third level Lv3, so the control device 13 does not enter the area Aa and turns. The path setting device 41 resets the driving path based on this.

[0067] According to the above structure, when the vehicle 1 is automatically traveling, the driving device 14 is controlled differently according to the road condition level ahead of the vehicle position in the traveling direction. Therefore, in a place with poor road conditions, such as low-speed driving, the driving control of the automatic driving can be changed from the control in a place with good road conditions. Therefore, in the vehicle 1 that can travel on rough terrain, appropriate automatic driving control corresponding to the road conditions can be performed.

[0068] In addition, the allowable range of the driving parameter may also set a lower limit in addition to an upper limit. For example, the control device 13 may also set an upper limit value of the speed and a lower limit value of the speed (the minimum speed during normal driving) when the road surface condition level is the second level Lv2 where driving restriction control should be performed. Thus, even when driving at a low speed, appropriate driving control can be performed on a road surface where the vehicle 1 may get stuck. That is, the possibility of the vehicle 1 getting stuck can be reduced.

[0069] Furthermore, the driving parameters of the control object are not limited to the above examples. For example, the driving parameters may include acceleration, gear ratio, suspension damping force, vehicle height, etc. in addition to the above speed and steering angle. For example, when the road surface condition level is the second level Lv2 where driving restriction control should be performed, the control device 13 controls the driving device 14 in a form in which the acceleration is less than the predetermined reference acceleration. This can prevent slippage caused by rapid acceleration on a slippery road surface.

[0070] Furthermore, for example, when the vehicle 1 is provided with a transmission device (having multiple stages) that can selectively switch between multiple speed ratios (ratios of the rotation speed of the output shaft of the drive source 9 to the rotation speed of the output shaft of the transmission device), the control device 13 controls the travel device 14 in a manner that makes the speed ratio lower than the reference speed ratio (higher than the reference stage) among the multiple speed ratios when the road surface condition level is the second level Lv2 at which the travel restriction control should be performed. This can prevent slippage caused by an increase in output torque on a slippery road surface.

[0071] Furthermore, for example, when the vehicle 1 is provided with a damping force adjustment mechanism such as hydraulic control or electronic control of the suspension, the control device 13 controls the travel device 14 in a manner such that the damping force of the suspension is reduced when the road surface condition level is the second level Lv2 at which the travel restriction control should be performed. Furthermore, for example, when the vehicle 1 is provided with a vehicle height adjustment mechanism, the control device 13 controls the travel device 14 in a manner such that the vehicle height is increased when the road surface condition level is the second level Lv2 at which the travel restriction control should be performed.

[0072] The control device 13 obtains prescribed data related to the vehicle loading condition or the external environment of the vehicle 1 from the data receiving unit 42, and can correct the allowable range associated with the road condition level based on the obtained data. For example, the vehicle 1 detects the weight of the cargo on the loading platform 8 and / or the number of people seated in each seat 5A, 5B. The detected weight of the cargo and / or the number of people seated are sent to the control device 13 via the data receiving unit 42.

[0073] For example, when the weight of the cargo is greater than a predetermined reference weight and / or the number of people seated is greater than a predetermined reference number, the control device 13 changes the permissible range of the driving parameter that is the control object under the driving restriction control when the road surface condition level is the second level Lv2 to a narrower range. For example, in the above example, when the road surface condition level is the first sub-level Lv2-1, the control device 13 changes the permissible range of the speed to less than the second reference speed V2 that is lower than the first reference speed V1.

[0074] Alternatively, the control device 13 may also change the road surface condition level to a higher level (a level with stricter restrictions) when the weight of the cargo is greater than a predetermined reference weight and / or the number of people seated is greater than a predetermined reference number. That is, in the above example, the control device 13 may perform a driving restriction control of the second sub-level Lv2-2, i.e., speed restriction, and steering angle restriction, when the road surface condition level is the first sub-level Lv2-1. Furthermore, the control device 13 may perform a control of the third level Lv3, i.e., a control to avoid the vehicle 1 from entering the area, when the road surface condition level is the second sub-level Lv2-2.

[0075] In addition, as data related to the external environment of the vehicle 1, the vehicle 1 can include, for example, weather, temperature, air pressure, season, date and time, region (climate zone), type of ground (muddy land, wetland, beach, desert, etc.). One of these data can be used, or a combination of multiple data can be used. The data related to the external environment (such as weather, season, date and time, region, etc.) is stored in a server device connected to the data receiving unit 42 of the vehicle 1 through a communication network, and is sent from the server device to the data receiving unit 42. Alternatively, the data related to the external environment (such as temperature, air pressure, road surface conditions, etc.) can be, for example, values ​​detected by sensors provided on the vehicle 1.

[0076] For example, when it is raining or the air pressure is below a predetermined reference air pressure, the control device 13 may change the permissible range of the driving parameter that is the control object under the driving restriction control when the road surface condition level is the second level Lv2 to a narrower range, or change the road surface condition level to a higher level. Also, for example, when the vehicle is traveling on a muddy ground or other ground that is prone to getting stuck, or when the air temperature is below a predetermined reference temperature (e.g., below freezing), the control device 13 may set the minimum speed during normal driving to be above the third reference speed V3.

[0077] In this way, by changing the allowable range of the driving parameter according to the road condition level in accordance with the change in the weight of the vehicle 1 or the change in the external environment, it is possible to perform driving control that is more in line with the actual situation.

[0078] (Estimation of road conditions)

[0079] The vehicle 1 includes a road surface condition estimation device 43 that generates road surface condition data. The road surface condition estimation device 43 may be configured as a functional block of the control device 13 or may be configured as a computing device independent of the control device 13 .

[0080] The road condition estimation device 43 estimates the road condition at the vehicle position from a predetermined driving index, and determines which of a plurality of pre-set road condition levels the estimated result belongs to, thereby generating road condition data. The driving index is at least one index indicating the driving state of the vehicle 1, and is acquired by the driving index acquisition device 44.

[0081] For example, in the above example, the driving index is a pitch angle and / or a roll angle indicating the posture of the vehicle 1. Therefore, the driving index acquisition device 44 includes the pitch angle sensor 22 and / or the roll angle sensor 23. In addition or in place of this, the driving index acquisition device 44 may include other various sensors 15 to 21 according to the driving index to be acquired. Figure 2In the example, the driving index acquirer 44 includes various sensors 15 to 23 and a digital model forming unit 45 described later. However, if a sensor for obtaining the expected driving index functions as the driving index acquirer 44, other sensors may not function as the driving index acquirer 44.

[0082] For example, the driving index may include a second driving index indicating the force applied to the front wheel 2 and / or the rear wheel 3 (hereinafter, force on the wheel) in addition to or instead of the first driving index indicating the posture of the vehicle 1 .

[0083] The first driving index indicating the posture of the vehicle 1 can be obtained by directly measuring the pitch angle and / or the roll angle as described above. In addition, the driving index acquirer 44 can also use one or more indicators from the accelerator opening, braking amount, steering angle, rotation speed of the output shaft of the driving source 9, vehicle speed, wheel rotation speed, suspension stroke, etc. to correct the first driving index.

[0084] The second driving index indicating the force on the wheels of the vehicle 1 includes, for example, the slip rate of each wheel. The slip rate is obtained by measuring the vehicle speed and the wheel speed, finding the deviation of the wheel speed relative to the vehicle speed, and dividing the deviation by the vehicle speed. In addition, the driving index acquisition device 44 may also use one or more indicators from the accelerator opening, braking amount, steering angle, rotation speed of the output shaft of the driving source 9, suspension stroke, pitch angle, roll angle, etc. to correct the second driving index.

[0085] Furthermore, the acquisition of the driving index is not limited to directly acquiring the values ​​measured by various sensors. For example, the driving index acquirer 44 may also include a digital model forming unit 45 that forms a digital model of the vehicle 1. In this case, the driving index acquirer 44 detects at least one vehicle state value indicating the state of the vehicle 1. The digital model forming unit 45 forms a digital model related to the driving state of the vehicle 1 from the at least one vehicle state value. The driving index acquirer 44 extracts the driving index from the digital model. For example, the digital model forming unit 45 may also use state values ​​related to the posture of the vehicle 1, such as a pitch angle and a roll angle, as vehicle state values ​​to form a digital model of the vehicle 1. The driving index acquirer 44 may also extract the grip force of each wheel 2, 3 of the formed digital model as a driving index.

[0086] In addition, when acquiring the driving index, the driving index acquirer 44 may correct the driving index based on the detection result of the front space detection unit 29. For example, when the front space detection unit 29 is a camera, the driving index acquirer 44 analyzes the image in front of the vehicle 1 captured by the front space detection unit 29 to estimate the friction coefficient of the driving road surface. The driving index acquirer 44 uses the acquired friction coefficient to correct the driving index acquired from the measurement or digital model. For another example, the driving index acquirer 44 may also analyze the image in front of the vehicle 1 captured by the front space detection unit 29 to estimate the posture of the vehicle 1 and correct the driving index based on the estimated posture.

[0087] The road condition estimation device 43 estimates the road condition of the driving path in the human-operated mode, associates the driving path with the road condition level, and generates road condition data. At this time, the driving index acquisition device 44 acquires the driving index of the vehicle position during driving in the manned driving mode. The road condition estimation device 43 estimates the road condition from the driving index of the vehicle position, and determines which of the multiple road condition levels the road condition at the vehicle position belongs to.

[0088] The control device 13 stores the road surface condition level of the vehicle position obtained by determination in association with the data of the vehicle position. If the data of the road surface condition level of the same position has already been stored, the control device 13 may overwrite the new data as the data of the position, or may perform processing such as averaging the stored data and the new data and update them. In addition, the area in the driving area SA that has not been driven in the past is set as a driving-unable area. The storage location of the road surface condition data may be a memory in the vehicle 1, or a storage device (a server device or a mobile terminal, etc.) outside the vehicle 1 that can communicate via a communication network.

[0089] In this way, the road condition estimation device 43 stores the road condition level of the travel path in the manual operation mode in association with the vehicle position, thereby mapping the road condition level of the predetermined travel area SA. The mapped data is stored as road condition data (road condition map).

[0090] In this way, the road surface condition data generated during driving by human operation can be generated, and the road surface condition data that is safe and conforms to the actual road surface condition can be generated.

[0091] In addition, regarding the road condition of the area not traveled in the manual operation mode within the travel area SA, the road condition estimation device 43 can apply adjacent road condition data by analogy and also regard it as a travel-unavailable area (third level Lv3).

[0092] Furthermore, the road surface condition estimating device 43 may also estimate the road surface condition of the driving path of the vehicle 1 when the vehicle 1 is driving automatically, using the road surface condition data generated in the above-mentioned manual operation mode, and update the road surface condition data.

[0093] Instead of using the map of the road surface condition level in the manned driving mode, the vehicle 1 travels in the automatic driving mode without performing driving control taking the road surface condition into consideration, whereby the road surface condition estimating device 43 can acquire the driving index and estimate the road surface condition based thereon.

[0094] For example, the control device 13 drives the driving device 14 so that the vehicle 1 automatically drives according to a predetermined driving pattern or a driving route set by a user. The road surface condition estimation device 43 estimates the road surface condition at that time, associates the driving route with the road surface condition level, and generates road surface condition data. For example, if the vehicle 1 overturns, the posture (roll angle, pitch angle, etc.) of the vehicle 1 exceeds the reference range, or the vehicle 1 cannot drive due to being stuck, etc., the road surface condition level at that position is set to the third level Lv3.

[0095] In this way, the vehicle 1 is driven automatically to generate road condition data, so that road condition data that matches the actual road condition can be generated without much effort. In addition, the road condition estimation device 43 can also estimate the road condition of the driving path when driving in the automatic driving mode using the above-mentioned road condition data, and update the road condition data.

[0096] Alternatively, the road condition data may be generated by performing a driving simulation of a virtual vehicle simulating the vehicle 1. The driving simulation may be performed by the road condition estimation device 43, or by a computer outside the vehicle 1 that can communicate with the vehicle 1 via a communication network, or by an independent computer that does not communicate with the vehicle 1, and the road condition data obtained as a result is transferred to a memory of the vehicle 1 via a storage medium or the like.

[0097] During the driving simulation, terrain data of the driving area SA is prepared. The terrain data is generated from satellite images, for example. The computer performing the driving simulation generates a virtual driving space based on the road surface shape data of the driving area SA. The computer also generates a virtual vehicle simulating the vehicle 1 and arranges it in the virtual driving space.

[0098] The computer performs a driving simulation in which a virtual vehicle drives in the generated virtual driving space. The virtual vehicle changes its driving state according to the changes in the terrain of the virtual driving space. The posture of the virtual vehicle at this time or the force on the wheels is obtained as a driving index to estimate the road surface condition. Based on the estimated results of the road surface condition, the computer divides the virtual driving space into a plurality of road surface condition levels to generate road surface condition data (road surface condition map). Machine learning can be used in such driving simulation.

[0099] For example, machine learning may be performed to classify a plurality of road condition levels by supervised learning, or different road condition levels may be assigned to a plurality of road condition levels classified by unsupervised learning, and the allowable range of the corresponding driving parameter may be determined.

[0100] The road condition data in the virtual driving space obtained in the driving simulation is used as the road condition data in the actual driving area SA. In addition, the road condition estimation device 43 can also estimate the actual road condition of the driving path when driving in the automatic driving mode using the above road condition data and update the road condition data.

[0101] In this way, by generating the road surface condition data through the driving simulation, it is possible to generate safe road surface condition data that covers the entire driving area SA.

[0102] The road condition data includes the road condition levels such as Figure 3 As shown in the example shown, it can be set to one dimension based on one viewpoint (the posture of the vehicle 1), but it can also be set to two dimensions or more dimensions by combining multiple viewpoints. For example, it is also possible to combine a one-dimensional first road condition level based on the vehicle posture and a one-dimensional second road condition level matrix based on the estimated friction coefficient of the road surface to generate road condition data having a two-dimensional road condition level.

[0103] For example, in the case of a road with a low first road condition level (a flat or gently inclined road) and a road with a high second road condition level (a slippery road), the control device 13 can control the maximum speed during rapid acceleration or steering. In such a case, the vehicle may be on muddy or water (crossing a river), so the control device 13 controls the vehicle 1 to travel at a speed higher than the preset minimum speed to prevent the vehicle 1 from getting stuck.

[0104] Furthermore, when the vehicle 1 is traveling, the road condition is estimated, and data related to the external environment at that time (for example, the weather, temperature, air pressure, season, date and time, region, type of ground, etc., as described above) is obtained, and the road condition level of the location can be set to different levels according to the index of the external environment. For example, the road condition level on a sunny day is the first sub-level Lv2-1, and the road condition level on a rainy day is the second sub-level Lv2-2, and the road condition level at one location can be set to multiple levels according to other conditions.

[0105] Furthermore, the control device 13 may also determine the road surface condition level of each of the left and right wheels 2 and 3 as the road surface condition ahead of the vehicle 1 in the traveling direction. In this case, for example, the control device 13 detects the roll angle, and when the roll angle is equal to or greater than the reference value, it is determined that the vehicle 1 is in a state of moving forward in an intersecting manner relative to the inclination. When the control device 13 determines that the vehicle 1 is in a state of moving forward in an intersecting manner relative to the inclination, and when the road surface condition level is the second level Lv2 at which the driving restriction control (speed restriction) should be performed, in addition to the speed restriction, the control device 13 may also limit the steering angle range, and when the control device 1 determines that the vehicle 1 is not in a state of moving forward in an intersecting manner relative to the inclination, and when the road surface condition level is the second level Lv2, the speed restriction is performed but the steering angle range is not restricted.

[0106] Similarly, the control device 13 may determine the road surface condition level of each of the four front, rear, left and right wheels as the road surface condition ahead in the traveling direction of the vehicle 1 .

[0107] again, Figure 3 In the example, the road surface condition level (second level Lv2) for driving restriction control includes two sub-levels Lv2-1 and Lv2-2 with different allowable ranges of driving parameters or types of driving parameters, but the present invention is not limited thereto. That is, the road surface condition level (second level Lv2) for driving restriction control may correspond to one control content, or may include three or more sub-levels.

[0108] Multiple road conditions that can make the allowable range of driving parameters or the types of driving parameters different (capable of driving restriction control) include, for example, wet asphalt roads, gravel roads, farmlands, grasslands, steep slopes, rivers, rocks, snow, mud, beaches, deserts, etc.

[0109] The road surface condition data generated in each of the above-mentioned forms can also be used to set the driving route. That is, the route setting device 41 can also set the driving route based on the road surface condition data. For example, when multiple driving routes can be set when moving the vehicle 1 from the current position to the expected destination, the route setting device 41 adopts a shorter driving route on the driving route whose road surface condition level is a predetermined level (for example, the second sub-level Lv2-2) or higher that can be driven.

[0110] Alternatively, when the user can set a priority condition when setting the driving route, the route setting device 41 sets a driving route that better satisfies the priority condition. For example, when the vehicle 1 is moved to the desired destination, when the driving route is set with distance priority, the route setting device 41 allows the use of a route with a road surface condition level of a certain higher level (for example, the second sub-level Lv2-2) or higher. For example, when the vehicle 1 is moved to the desired destination, when the driving route is set with time priority, the route setting device 41 takes into account the speed limit corresponding to the road surface condition level and uses a driving route with a shorter arrival time.

[0111] For example, when the vehicle 1 is moved to a desired destination, the route setting device 41 sets a driving route with a priority of reducing the posture change of the vehicle 1, and the route setting device 41 adopts a shorter driving route on a driving route with a road surface condition level of a predetermined level (e.g., the second sub-level Lv2-2) or higher that is drivable. In this case, the route setting device 41 may further set a driving route in which there are fewer states in which the road surface condition levels of the left and right roads on which the left and right wheels 2 and 3 respectively touch the ground are different.

[0112] Furthermore, when the actual driving or machine-learned road condition data is generated, a group of routes that the vehicle 1 or a virtual vehicle travels (and is not unable to travel) may be registered as a candidate driving route. The route setting device 41 may select the best route from the setting data of the driving route based on the destination, etc. in the route group, or may combine a plurality of routes included in the route group and set it as the driving route.

[0113] By setting a travel route according to the road surface condition data, the number of changes to the travel route during automatic travel can be reduced, and efficient travel of the vehicle 1 can be achieved.

[0114] In addition, data other than road conditions may also be included as other conditions for setting the driving route. For example, the front space detection unit 29 is configured to detect a surveillance object such as a person or an animal by analyzing a captured image, etc. During automatic driving or manual driving, when the front space detection unit 29 finds a surveillance object, the control device 13 stores the vehicle position at that time as encounter history data in a memory, etc. During manual driving, a user riding in the vehicle 1 performs a prescribed operation input, so that the vehicle position at the time of the operation input can be registered as the location where the surveillance object is detected. The route setting device 41 may also change part or all of the driving route based on the encounter history data.

[0115] For example, the path setting device 41 may also set a driving path that avoids locations where the surveillance object is frequently encountered. This can reduce the risk of contact with people or animals. In addition, when the vehicle 1 is driven in a conflict area or an area with poor public security, for example, for the purpose of transporting materials, the possibility of the vehicle 1 being attacked or the cargo being robbed can be reduced.

[0116] Alternatively, the path setting device 41 may set a driving path that preferentially passes through a location where the surveillance object is encountered more frequently. Thus, for example, when the vehicle 1 is patrolling (surveilling) in the driving area SA in a vast farmland or forest, a driving path with a high detection efficiency can be set.

[0117] For example, the front space detection unit 29 is configured to detect light emission by analyzing a captured image during nighttime driving, and when the front space detection unit 29 detects light emission (a residential building, a searchlight, a spark, etc.) during automatic driving or manual driving at night, the control device 13 stores the vehicle position at that time as light emission history data in a memory, etc. During manual driving, a user riding in the vehicle 1 performs a predetermined operation input, so that the vehicle position at the time of the operation input can be registered as the location where the light emission is detected. The route setting device 41 can change part or all of the driving route based on the light emission history data.

[0118] (Other Implementations)

[0119] As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, Various improvements, changes, and corrections can be made within the range which does not deviate from the summary.

[0120] For example, in the above embodiment, the common control device 13 performs either the control of the manual operation mode or the control of the automatic driving mode, but the present invention is not limited thereto. For example, the vehicle 1 may include a first control device (first ECU) that performs the control of the vehicle 1 in the manual operation mode and a second control device (second ECU) that performs the control of the vehicle 1 in the automatic driving mode.

[0121] Furthermore, in the above embodiment, the vehicle 1 that can be driven by human operation is exemplified, but the control of the automatic driving mode in the above embodiment can also be applied to a vehicle 1 that is dedicated to automatic driving.

[0122] Furthermore, in the above-mentioned embodiment, the vehicle 1 is illustrated as being provided with the road surface condition estimation device 43, but it is not necessary to provide the road surface condition estimation device 43. That is, as long as the control device 13 is configured to obtain road surface condition data from the storage unit of the vehicle 1 or an external storage device, determine which of a plurality of road surface condition levels the road surface condition ahead of the vehicle position in the traveling direction belongs to, and control the driving device 14 in a manner such that the prescribed driving parameters correspond to the plurality of road surface condition levels and are within a preset allowable range, no other configuration is necessary.

[0123] The road condition data in the above embodiment may be data common to a plurality of vehicle types. However, if the driving capabilities differ between vehicle types, the permissible range of driving parameters or the type of driving parameters corresponding to one road condition level may differ for each vehicle type.

[0124] For example, in the case of the first vehicle with high bad road handling performance, as in the above example, the driving control is performed in the form of speed restriction at the first sub-level Lv2-1, and driving restriction and steering range restriction at the second sub-level Lv2-2. On the other hand, in the case of the second vehicle with lower bad road handling performance than the first vehicle, the speed may be restricted to a lower speed and steering range restriction at the first sub-level Lv2-1, and control may be performed to avoid the vehicle 1 from entering the area at the second sub-level Lv2-2.

[0125] Therefore, the driving level divided into multiple levels based on the driving ability of the vehicle 1 can also be stored in a memory or the like as data read by the control device 13 when performing driving control. Alternatively, the control device 13 reads the driving level of the vehicle 1 after determining the road surface condition level, thereby determining the driving control content corresponding to the road surface condition level and the driving level.

[0126] Explanation of symbols:

[0127] 1 Multipurpose vehicle (vehicle)

[0128] 2 Front wheels

[0129] 3 Rear wheels

[0130] 9. Drive source

[0131] 10, 12 Operating parts

[0132] 11 Steering device

[0133] 13 Control Devices

[0134] 14 Traveling device

[0135] 30 Vehicle position detection unit

[0136] 41 Path setting device

[0137] 43 Road condition estimation device

[0138] 44 Driving Index Acquisition Device

[0139] 50 Mode switching unit.

Claims

1. A multi-purpose vehicle, characterized in that: A travel device including front wheels and rear wheels, a steering device provided on the front wheels, and a driving source for driving the front wheels and / or the rear wheels; A control device for controlling the travel device so as to automatically travel in a prescribed travel area without requiring human operation; a vehicle position detection unit for detecting a vehicle position; a driving index acquirer for acquiring at least one driving index indicating a driving state of a vehicle; and a road surface condition estimating device for estimating a road surface condition at the vehicle position from the driving index; During the automatic driving, the control device controls the driving device as follows: Based on the road condition data that divides the travel area into a plurality of predetermined road condition levels, determining to which of the plurality of road condition levels the road condition ahead of the vehicle in the direction of travel belongs, Make the prescribed driving parameters correspond to the plurality of road condition levels respectively and be within a preset allowable range; The road surface condition estimation device determines which of the plurality of road surface condition levels the road surface condition belongs to based on the estimation result of the road surface condition, thereby generating the road surface condition data; The running index includes a first running index indicating a posture of a vehicle and a second running index indicating a force applied to the front wheel and / or the rear wheel.

2. The utility vehicle according to claim 1, characterized in that: The control device acquires predetermined data related to a vehicle loading condition or an external environment of the vehicle, and corrects the allowable range associated with the road surface condition level based on the predetermined data.

3. The multi-purpose vehicle according to claim 1 or 2, characterized in that: The driving parameter includes at least one of speed, acceleration and steering angle.

4. The multi-purpose vehicle according to claim 1 or 2, characterized in that: The road condition levels include: a first level when the inclination angle of the vehicle is less than the first angle or the roll angle is less than the first roll angle; The inclination angle is a second level when the inclination angle is greater than or equal to the first angle and less than a second angle greater than the first angle; and The third level when the inclination angle is greater than the second angle; The driving parameters include speed; The control device controls the driving device without performing a speed limit based on the road surface condition level when the road surface condition level is the first level, controls the driving device in a manner such that the speed is lower than a first reference speed when the road surface condition level is the second level, and controls the driving device in a manner such that entry is avoided when the road surface condition level is the third level.

5. The multi-purpose vehicle according to claim 1 or 2, characterized in that: A path setting device is provided for setting a driving path of the automatic driving; The route setting device sets the travel route based on the road surface condition data.

Images