Patent Description:
<CIT> discloses an agricultural work machine that can work in various operation modes. The agricultural work machine downloads agricultural work information to classify a target agricultural work, compares a set setting work mode to a registration work mode included in the downloaded agricultural work information, and displays a comparison result on a display. Based on the comparison result displayed on the display, an operator can easily and surely recognize whether a work mode currently set to the agricultural work machine agrees with a work mode previously registered in a management center. The work mode includes setting parameters, such as an orientation of a work device and a travel speed, of the work machine defined to perform various operations, and use of the correct work mode allows the work as planned to be performed.

In order to reduce a burden on a driver in the work traveling, <CIT> discloses a driving support system, in which the content of a series of operations performed by manual operation during work traveling is recorded and then the recorded content of the operations is reproduced to automatically perform the content of the series of operations. The driving support system includes: a device controlling unit that outputs an operation control signal to a traveling operation device that causes a traveling vehicle body to travel and a work operation device that causes the ground work device to perform an operation; a recording unit that records control data corresponding to the operation control signal as a work traveling sequence in order of execution processes; a reproducing unit that reads the control data recorded in the recording unit and provides the control data to the device controlling unit; a screen processing unit that displays a work traveling sequence screen, on which icons converted from the control data in each execution process unit are displayed in the order of the execution processes, on the display; and a plural-work traveling management unit that manages a plurality of the work traveling sequences on the same work traveling sequence screen.

In the agricultural work machine of <CIT>, a setting parameter of each work machine is appropriately set by checking the work mode before the start of work traveling. However, because whether the setting parameter is appropriate is not checked after the start of work traveling, even if the setting parameter is changed due to a breakdown, the work traveling is continued without being aware of the change.

In the driving support system of <CIT>, the same work traveling is accurately repeated by reproducing the once recorded sequence data of a specific work traveling. However, in such a recording and reproducing system, even if there is a deviation is generated in the work traveling sequence due to a trouble with a control function unit that manages reproduction timing or a trouble with a work machine, the work traveling is continued without being aware of the trouble.

An automatic travelling work vehicle performing work travelling along a travel route is known from <NPL>.

Further, a GPS-based guidance for an agricultural machine is disclosed in <NPL>.

Document <CIT> discloses an in-vehicle electronic control device for diagnosing the details of an abnormality of a microcomputer. A monitoring function for detecting a malfunction by monitoring input / output of a main function of a hardware part and a monitoring function for detecting an abnormality by monitoring the calculating result of a main function in a software part are provided in a microcomputer. The main function to be monitored is implemented with a different structure than the malfunction / abnormality monitoring function. Furthermore, a malfunction processing circuit for monitoring an abnormality of the microcomputer is provided outside the microcomputer.

It is an object to provide an automatic traveling work vehicle and a method for controlling work traveling for an automatic traveling work vehicle along a travel route that can monitor whether the work traveling is appropriately performed along the travel route.

For solving the problem, an automatic traveling work vehicle and a method for controlling work traveling for an automatic traveling work vehicle along a travel route of claims <NUM> and <NUM>, respectively, are provided. Further embodiments are disclosed in dependent claims.

The term of "work traveling" as used here may include at least one of the following: performing the work during the traveling, only traveling, only performing the work, performing at least one of the items, and a pause of the traveling work. For example, the work traveling may refer to work during traveling in a work area such as a field.

According to the configuration, the actual work event command is generated by actually operating the device in order to yield the work event (such as a change of a vehicle speed, a change of a direction of the vehicle body, and a change of an orientation of the work device) defined in the work event plan, and the virtual work event command is generated as a dummy by a system separated from the generation of the actual work event command. Accordingly, when the work vehicle reaches the work event planning point where the execution of the predetermined work event is planned while performing the automatic traveling along the predetermined travel route, the work traveling monitoring unit checks the actual work event command and virtual work event command for the work event. When the extracted actual work event command and virtual work event command are output at the substantially same timing, and when the extracted actual work event command and virtual work event command have the same work event content, the work traveling is determined to be normal. Otherwise, it can be determined that the abnormality is generated in the work traveling. When the virtual work event command is not output at the time the actual work event command is output, it can be determined that the abnormality is generated in a sensor, an operation device, a signal line, or a data line, which is used to perform the work event. There are many work events to be performed during the work traveling along the travel route, and whether the actual work event command is correct is checked in the time each work event is performed. Therefore, any abnormality can quickly be detected on the work traveling, and recovery from abnormality generation can be performed at an early stage.

In the automatic traveling work vehicle, a first controlling unit includes the travel route generation unit, the work event planning unit, and the virtual work event command generation unit. A second controlling unit includes the actual work event command generation unit. A third controlling unit includes the work traveling monitoring unit. The first controlling unit, the second controlling unit, and the third controlling unit are constructed as an independent control system. Therefore, even if a trouble such as a communication failure of the signal or the data is generated, the trouble is limited only to the controlling unit in which the communication failure is generated, so that monitoring reliability of the work event by the work traveling monitoring unit is enhanced.

In an exemplary embodiment, in the automatic traveling work vehicle, the first controlling unit is configured as a data processing terminal equipped with a touch panel and having an input and output function. In the first controlling unit, not only functional units, such as a travel route generation unit and the work event planning unit, which require the operation of the user, are constructed, but also a data capacity related to the travel route and the work event is increased in a large-scale work traveling. Therefore, a large calculation capability is required to perform the functions of the travel route generation unit and the work event planning unit. Therefore, the data processing terminal with the input and output function having the high-level user interface and high calculation capability is usefully used as the first controlling unit unlike other controlling units.

In an exemplary embodiment, in the automatic traveling work vehicle, the work traveling monitoring unit compares the actual work event command related to the work event with the virtual work event command when the automatic traveling work vehicle travels along the travel route to which the work event is allocated, and the work traveling monitoring unit determines the abnormality of the work traveling when the actual work event command and the virtual work event command do not correspond to each other. When the actual work event command and the virtual work event command do not correspond to each other in terms of the content or timing, the control system fails but the work traveling is not performed as planned, so that it is determined that the abnormality is generated in the work traveling. Because the abnormality is considered to be caused by a communication error of the data or signal, a failure of a sensor, or a failure of various work traveling devices, the abnormality process including stop of work traveling is performed.

The embodiments disclosed above with regard to the automatic traveling work vehicle may apply to the method for controlling work traveling for an automatic traveling work vehicle along a travel route mutatis mutandis.

A tractor for agricultural work is cited as an automatic traveling work vehicle according to an exemplary embodiment. <FIG> is a side view of the tractor. In the tractor, an engine <NUM> is mounted on a front portion of a vehicle body <NUM> of the tractor supported by front wheels 2a and rear wheels 2b, and a transmission <NUM> is mounted behind the engine <NUM>. A tilling device <NUM> is liftably mounted on a rear portion of the vehicle body <NUM> with a lifting mechanism <NUM> interposed therebetween. The tractor is of a four-wheel drive type, and power of the engine <NUM> is transmitted to the front wheels 2a and the rear wheels 2b, which can function as a drive wheel, through a transmission mechanism incorporated in the transmission <NUM>. The power of the engine <NUM> is also transmitted to the tilling device <NUM> though a PTO shaft <NUM> protruding rearward from the transmission <NUM>.

The engine <NUM> is covered with a hood <NUM>. A cabin <NUM> is supported on the vehicle body <NUM> behind the hood <NUM> and above the transmission <NUM>.

An interior of the cabin <NUM> functions as a driving space, a steering wheel <NUM> that performs steering operation of the front wheels 2a though a steering mechanism (not illustrated) is disposed in a front portion of the cabin <NUM>, and a driver's seat <NUM> is disposed between a pair of right and left rear fenders <NUM> in a rear portion of the cabin <NUM>. An armrest operation device <NUM> having various operation tools is provided from the side to the front of the driver's seat <NUM>. A data processing terminal with an input and output function that functions as a first controlling unit <NUM> is disposed in front of the armrest operation device <NUM>. The data processing terminal (first controlling unit <NUM>) is a tablet computer, is provided with a touch panel <NUM>, can receive various operation inputs by the driver, and can notify the driver of various pieces of information.

Although not illustrated, a control lever that raises and lowers the tilling device <NUM> through the operation of the lifting mechanism <NUM>, a shift lever that switches gears in the transmission <NUM>, a drive mode switching lever that switches between <NUM> WD and <NUM> WD, and an engine speed adjustment lever that adjusts the engine speed are disposed in the armrest operation device <NUM>.

<FIG> schematically illustrates an example of work traveling performed by the tractor. In the example of <FIG>, the travel route in which the tractor automatically travels is a zigzag travel route including a plurality of straight routes and a U-turn route connecting the straight routes. In the travel route, when the tractor travels along the straight route, tilling work is performed by lowering the tilling device <NUM> (one example of the work event). When the tractor travels along the U-turn route, the tilling work is stopped by raising the tilling device <NUM>, and the traveling is performed while the tilling work is stopped (one example of the work event). A direction of the vehicle body <NUM> is changed by taking in U-turn traveling in which steering control is used or switch back traveling in which reverse is used (one example of the work event).

In the example of <FIG>, a work event planning point (indicated by S1, S2,. in <FIG>) is set along the planned travel route. A work event (indicated by E1, E2,. in <FIG>) performed at each work event planning point and a position on a map (indicated by P1, P2,. in <FIG>) are allocated to each work event planning point. The work event includes a parameter (indicated by e11, e12,. in <FIG>) determining an operation state (such as a vehicle speed, a gear position, and a steering angle) of the vehicle body <NUM> or an operation state (such as a tilling depth and a raised position) of the tilling device <NUM>, and a specific work event is performed based on the parameter. The position on the map is represented by a coordinate position (indicated by (x1, y1), (x2, y2),.

<FIG> is a functional block diagram illustrating a control function of the tractor. As illustrated in <FIG>, a control system of the tractor includes a first controlling unit (data processing terminal) <NUM>, a second controlling unit <NUM>, and a third controlling unit <NUM>, which are particularly related to the control of the work traveling monitoring. Although the first controlling unit <NUM>, the second controlling unit <NUM>, and the third controlling unit <NUM> are connected to one another through an in-vehicle LAN, the first controlling unit <NUM>, the second controlling unit <NUM>, and the third controlling unit <NUM> can be operated independently of one another, and configured such that a trouble occurring in one control unit does not affect another controlling unit.

A control device and a control function unit also included in a control system of a normal tractor will be described. In the control system in <FIG>, the functional units are connected to one another through a data and signal line (such as an in-vehicle LAN and a control signal line) indicated by a solid line such that data can be exchanged. However, an output processing unit, an input processing unit, and a communication unit, which function as an input and output interface, are omitted in <FIG>. The data and signal line is connected to vehicle traveling instruments <NUM> including operation devices for the engine <NUM>, the transmission <NUM>, and the steering mechanism, to work device instruments <NUM> including operation devices for the tilling device <NUM> and the lifting mechanism <NUM>, and to a notification device <NUM> including a buzzer, a speaker, and a lamp. The data and signal line is connected to an own vehicle position calculation unit <NUM>, traveling state detection sensors <NUM>, and work state detection sensors <NUM>. The own vehicle position calculation unit <NUM> calculates a coordinate position on the map of the vehicle body <NUM> based on positioning data from a satellite positioning module <NUM> in which GPS is used.

The data and signal line is also connected to a travel control unit <NUM> and a work control unit <NUM>. The travel control unit <NUM> has an automatic traveling control function and a manual traveling control function. When the automatic traveling control function is selected, a control signal generated based on the own vehicle position from the own vehicle position calculation unit <NUM> and the set travel route is outputted to the steering mechanism, and the automatic traveling is performed along the travel route. When the manual traveling control function is selected, the manual traveling is performed based on the operation of the steering wheel <NUM> by a driver. Similarly, the work control unit <NUM> also has an automatic work control function of automatically operating the tilling device <NUM> and the lifting mechanism <NUM> based on the above work event, and a manual work control function using various operation tools.

The first controlling unit <NUM> is configured as a data processing terminal using a tablet computer. The first controlling unit <NUM> includes the touch panel <NUM>, a work plan production unit <NUM>, and a virtual work event command generation unit <NUM>, and the work plan production unit <NUM> includes a travel route generation unit <NUM> and a work event planning unit <NUM>.

The work plan production unit <NUM> has a function of producing, using the touch panel <NUM>, a plan in which the tractor performs the work traveling along the travel route in the field. However, in the case that a work plan is previously produced, the work plan can also be received through communication or a storage media. The travel route generation unit <NUM> refers to field information including a landform of the field to be worked, and generates the travel route using a previously-installed travel route generation program. The work event planning unit <NUM> generates a work event plan that defines the work event performed during the work traveling along the travel route. <FIG> schematically illustrates a content of the work event plan. Based on the travel route, the work event plan, and the own vehicle position, when the own vehicle position reaches a coordinate position that is a predetermined work event planning point (actually, timing before the own vehicle position reaches the coordinate position), the virtual work event command generation unit <NUM> generates a virtual work event command to perform the work event.

The second controlling unit <NUM> includes a travel route setting unit <NUM>, a work event setting unit <NUM>, and an actual work event command generation unit <NUM>. The travel route setting unit <NUM> sets the travel route generated by the travel route generation unit <NUM> as a target travel route, readably develops the travel route in a memory, and provides the travel route to the travel control unit <NUM>. The work event setting unit <NUM> develops the work event described in the work event plan generated by the work event planning unit <NUM> and the coordinate position at which the work event is performed, in the memory in a readable form. Based on the work event plan developed in the memory, the travel route set by the travel route setting unit <NUM>, and the own vehicle position from the own vehicle position calculation unit <NUM>, the actual work event command generation unit <NUM> generates an actual work event command to perform a predetermined work event. The generated actual work event command is transferred to the work control unit <NUM>.

The third controlling unit <NUM> includes a work traveling monitoring unit <NUM> and an abnormality processing unit <NUM>. The work traveling monitoring unit <NUM> compares the actual work event command generated by the work event command generation unit <NUM> to the virtual work event command generated by the virtual work event command generation unit <NUM> at an arbitrary time, time the own vehicle position reaches the work event planning point, or time either the actual work event command or the virtual work event command is output, and the work traveling monitoring unit <NUM> determines that the abnormality is generated in the work traveling when the actual work event command and the virtual work event command do not correspond to each other or when the actual work event command and the virtual work event command cannot be compared to each other. The discrepancy between the actual work event command and the virtual work event command indicates that the parameters (indicated by e <NUM>, e <NUM>,. In <FIG>) included in the work events do not correspond to each other or that execution times deviate from each other. The abnormality processing unit <NUM> performs the abnormality process according to the content of an abnormality when the work traveling monitoring unit <NUM> determines the abnormality. The abnormality process includes emergency stop of the vehicle body <NUM> and notification through a notification device <NUM>.

An example of a flow of control of the work traveling monitoring in the control system of the tractor will be described below with reference to <FIG>.

Based on operation input by the user using the graphic user interface of the first controlling unit <NUM>, the work plan production unit <NUM> produces the work plan of the field that becomes a work target. The produced work plan includes the travel route for work traveling generated by the travel route generation unit <NUM> and the work event plan generated by the work event planning unit <NUM>.

The produced work plan is transmitted to the virtual work event command generation unit <NUM> and the actual work event command generation unit <NUM>. Although not illustrated in <FIG>, the travel route included in the work plan is transmitted to the travel route setting unit <NUM>.

When the work traveling is started, the virtual work event command generation unit <NUM> and the actual work event command generation unit <NUM> sequentially receive the own vehicle position from the own vehicle position calculation unit <NUM>. The actual work event command generation unit <NUM> extracts the work event having the coordinate position that agrees substantially with the received own vehicle position, and generates the actual work event command to perform the content of the work event. The generated actual work event command is provided to the work traveling monitoring unit <NUM>, the travel control unit <NUM>, and the work control unit <NUM>. Similarly, the virtual work event command generation unit <NUM> extracts the work event having the coordinate position that agrees substantially with the received own vehicle position, and generates the virtual work event command based on the content of the work event.

The generated virtual work event command is provided to the work traveling monitoring unit <NUM>. The work traveling monitoring unit <NUM> compares the received actual work event command to the received virtual work event command. When the received actual work event command and the received virtual work event command do not correspond to each other, the work traveling monitoring unit <NUM> determines that the abnormality is generated in the work traveling, and outputs abnormality information. Even when only one of the actual work event command and the virtual work event command is received, the work traveling monitoring unit <NUM> determines that the abnormality is generated in the work traveling, and outputs the abnormality information. According to the content of the abnormality information, the abnormality processing unit <NUM> performs an abnormality process to recover the abnormality. The abnormality process includes stop of the vehicle body <NUM>, stop of the tilling device <NUM>, a forced change from automatic operation to the manual operation, and a warning through the notification device <NUM> operated by the control signal from the notification unit <NUM>.

When either the virtual work event command or the real work event command is output at the time the own vehicle position is not received from the own vehicle position calculation unit <NUM>, the abnormality can be determined based on whether both the actual work event command and the virtual work event command are output or the comparison of the contents of the actual work event command and the virtual work event command to each other.

Claim 1:
A method for controlling work traveling for an automatic traveling work vehicle along a travel route, comprising:
- determining an own vehicle position based on positioning data from a satellite positioning module by an own vehicle position calculation unit (<NUM>);
- generating the travel route by a travel route generation unit (<NUM>);
- generating a work event plan defining a work event performed during the work traveling by a work event planning unit (<NUM>);
- controlling automatic traveling along the travel route by a travel control unit (<NUM>);
- generating an actual work event command based on the travel route, the work event plan, and the own vehicle position by an actual work event command generation unit (<NUM>); and
- controlling execution of the work event based on the actual work event command by a work control unit (<NUM>);
characterized by
- providing the travel route generation unit (<NUM>), the work event planning unit (<NUM>), and a the virtual work event command generation unit (<NUM>) in a first controlling unit (<NUM>);
- providing the actual work event command generation unit (<NUM>) in a second controlling unit (<NUM>);
- providing a work traveling monitoring unit (<NUM>) in a third controlling unit (<NUM>);
- providing the first controlling unit (<NUM>), the second controlling unit (<NUM>), and the third controlling unit (<NUM>) as an independent control system;
- operating independently of one another the first controlling unit (<NUM>), the second controlling unit (<NUM>), and the third controlling unit (<NUM>);
- generating a virtual work event command based on the travel route, the work event plan, and the own vehicle position by the virtual work event command generation unit (<NUM>);
- determining by the work traveling monitoring unit (<NUM>) an abnormality of the work traveling when the actual work event command and the virtual work event command do not correspond to each other, and outputting abnormality information; and
- performing an abnormality process to recover the abnormality according to the content of the abnormality information by an abnormality processing unit (<NUM>), wherein the abnormality process includes
- stopping a vehicle body (<NUM>);
- stopping a tilling device (<NUM>);
- forced changing from automatic operation to manual operation; and
- warning through a notification device (<NUM>) operated by a control signal from a notification unit (<NUM>).