Patent Description:
To date, an agricultural machine disclosed in PTL <NUM> is known. The agricultural machine (agricultural working vehicle) disclosed in PTL <NUM> can perform autonomous travel, includes an obstacle detector (obstacle detection means) that can detect an obstacle in front of a vehicle body, and can stop autonomous travel when detecting an obstacle.

<CIT> discloses an agricultural machine
comprising a collision avoidance system according to the preamble of claim <NUM>.

However, the agricultural machine disclosed in PTL <NUM>, which can stop the vehicle body when the obstacle detector detects an obstacle, may unnecessarily stop the vehicle body by detecting crop or the like as an obstacle depending on an agricultural field.

In consideration of such circumstances, an object of the present invention is to provide an agricultural machine that can change the condition for stopping autonomous travel in accordance with the circumstances.

The problem is solved by an agricultural machine according to claim <NUM>.

An agricultural machine includes: a vehicle body that is capable of traveling; an obstacle detector that is capable of detecting an obstacle; an autonomous travel controller that performs autonomous travel of the vehicle body and that, when performing the autonomous travel, stops travel of the vehicle body based on detection information about an obstacle detected by the obstacle detector; and a mode switcher that switches the autonomous travel controller between an effective mode in which the autonomous travel controller when performing the autonomous travel is allowed to stop travel of the vehicle body based on the detection information and an ineffective mode in which the autonomous travel controller when performing the autonomous travel is not allowed to stop travel of the vehicle body based on the detection information.

According to a further embodiment, the agricultural machine may include a support to which the obstacle detector is attached and that is capable of changing a position of the obstacle detector to a detection position where the obstacle detector is allowed to detect the obstacle and to a retracted position where the obstacle detector is not allowed to detect the obstacle, and the autonomous travel controller is allowed to perform the autonomous travel when the autonomous travel controller is in the ineffective mode and the obstacle detector is in the retracted position.

According to a further embodiment, the agricultural machine may include a seat-occupation detector that detects whether an operator's seat is occupied, and the autonomous travel controller is allowed to perform the autonomous travel when the seat-occupation detector is detecting that the operator's seat is occupied.

According to a further embodiment, the agricultural machine includes: a support to which the obstacle detector is attached and that is capable of changing a position of the obstacle detector to a detection position where the obstacle detector is allowed to detect the obstacle and to a retracted position where the obstacle detector is not allowed to detect the obstacle; and a switching restrainer that allows the mode switcher to switch from the effective mode to the ineffective mode when the obstacle detector is in the retracted position and does not allow the mode switcher to switch from the effective mode to the ineffective mode when the obstacle detector is in the detection position.

According to a further embodiment, the agricultural machine includes: a seat-occupation detector that detects whether an operator's seat is occupied; and a switching restrainer that allows the mode switcher to switch from the effective mode to the ineffective mode when the seat-occupation detector is detecting that the operator's seat is occupied and does not allow the mode switcher to switch from the effective mode to the ineffective mode when the seat-occupation detector detects that the operator's seat is not occupied.

According to a further embodiment, the agricultural machine includes a seat-occupation detector that detects whether an operator's seat is occupied, and the autonomous travel controller, when performing the autonomous travel, continues performing the autonomous travel when the seat-occupation detector is detecting that the operator's seat is occupied, and stops the autonomous travel when the seat-occupation detector detects that the operator's seat is not occupied.

According to a further embodiment, the agricultural machine includes a support to which the obstacle detector is attached and that is capable of changing a position of the obstacle detector to a detection position where the obstacle detector is allowed to detect the obstacle and to a retracted position where the obstacle detector is not allowed to detect the obstacle, and the autonomous travel controller, when performing the autonomous travel and in the ineffective mode, continues performing the autonomous travel when the obstacle detector is in the retracted position, and stops the autonomous travel when the position of the obstacle detector changes from the retracted position to the detection position.

According to a further embodiment, the agricultural machine includes a prime mover and an ignition switch that performs switching between ON and OFF of driving of the prime mover, and the mode switcher sets the effective mode as a default according to switching of the ignition switch from OFF to ON, and, when the ineffective mode is set, switches the ineffective mode to the effective mode according to switching of the ignition switch from ON to OFF.

According to a further embodiment, the agricultural machine includes a display that displays whether the autonomous travel controller is in the effective mode or in the ineffective mode.

The autonomous travel controller stops the vehicle body if the autonomous travel controller, when in the effective mode, acquires detection of an obstacle by the obstacle detector as the detection information.

The obstacle detector, even when detecting the obstacle, does not output detection of the obstacle to the autonomous travel controller when in the ineffective mode.

The obstacle detector notifies the autonomous travel controller when in the effective mode that an obstacle is detected during the autonomous travel, and does not notify the autonomous travel controller when in the ineffective mode that the obstacle is detected.

According to a further embodiment, the agricultural machine includes a support to which the obstacle detector is attached and that is capable of changing a position of the obstacle detector to a detection position where the obstacle detector is allowed to detect the obstacle and to a retracted position where the obstacle detector is not allowed to detect the obstacle; and the autonomous travel controller is allowed to start the autonomous travel when the autonomous travel controller is in the effective mode and the obstacle detector is in the detection position, is allowed to stop the autonomous travel when the autonomous travel controller is in the effective mode and the obstacle detector is in the retracted position, is allowed to stop the autonomous travel when the autonomous travel controller is in the ineffective mode and the obstacle detector is in the detection position, and is allowed to start the autonomous travel when the autonomous travel controller is in the ineffective mode and the obstacle detector is in the retracted position.

According to a further embodiment, the agricultural machine includes a seat-occupation detector that detects whether an operator's seat is occupied, and the autonomous travel controller is allowed to perform the autonomous travel when the seat-occupation detector is detecting that the operator's seat is occupied.

According to a further embodiment, the agricultural machine includes a switching restrainer that allows the mode switcher to switch from the effective mode to the ineffective mode when the obstacle detector is in the retracted position, and does not allow the mode switcher to switch from the effective mode to the ineffective mode when the obstacle detector is in the detection position.

With the present invention, it is possible to change the condition for stopping autonomous travel in accordance with the circumstances.

Hereafter, embodiments of the present invention will be described with reference to the drawings.

<FIG> and <FIG> illustrate an embodiment of an agricultural machine <NUM> according to the present invention. In describing the present embodiment, it is assumed that the agricultural machine <NUM> is a tractor <NUM>. However, the agricultural machine <NUM> may be, instead of a tractor, another agricultural machine (agricultural vehicle) such as a combine or a rice transplanter.

Hereafter, for convenience of description, the direction of arrow A1 in <FIG> and <FIG> will be referred to as the forward direction, the direction of arrow A2 will be referred to as the backward direction, the direction of arrow B1 will be referred to as the leftward direction, the direction of arrow B2 will be referred to as the rightward direction, and the direction of arrow D will be referred to as the vehicle-body width direction (or the width direction). A vehicle-body width direction away from a center in the vehicle-body width direction (the direction of arrow D1) will be referred to as the vehicle-body-width outward direction (or the outward direction), and a vehicle-body width direction toward a center in the vehicle-body width direction (the direction of arrow D2) will be referred to as the vehicle-body-width inward direction (or the inward direction).

Hereafter, the tractor will be described. As illustrated in <FIG> and <FIG>, the tractor <NUM> includes a vehicle body <NUM>, a prime mover <NUM>, and a transmission <NUM>. A travel device <NUM> is provided in the vehicle body <NUM>. The travel device <NUM> supports the vehicle body <NUM> so that the vehicle body <NUM> is capable of traveling, and has front wheels 7F and rear wheels 7R. The front wheels 7F and the rear wheels 7R, which are tires in the present embodiment, may be crawlers. The prime mover <NUM> is an engine (diesel engine, gasoline engine), an electric motor, or the like. The transmission <NUM> can switch the propelling force of the travel device <NUM> by speed change, and can switch between forward movement and backward movement of the travel device <NUM>. An operator's seat <NUM> is provided in the vehicle body <NUM>. The operator's seat <NUM> is protected by a protector <NUM>. In the present embodiment, the protector <NUM> is a cabin that protects the operator's seat <NUM> by surrounding the front, the back, the top, and the sides of the operator's seat <NUM>. However, the protector <NUM> may be a ROPS or the like that protects the operator's seat <NUM> by covering at least the top of the operator's seat <NUM>. Fenders <NUM> are attached to a lower part the protector <NUM>, and the fenders <NUM> cover upper parts of the rear wheels 7R.

A coupler (not shown), which includes a three-point linkage and the like, is provided in a back part of the vehicle body <NUM>. A working device (implement or the like) can be removably coupled to the coupler. By coupling the working device to the coupler, the working device can be pulled by the vehicle body <NUM>. The working device is a cultivator that performs cultivation, a fertilizer spreader that spreads fertilizer, an agricultural chemical spreader that spreads agricultural chemicals, a harvester that performs harvesting, a mower that performs mowing of grass and the like, a tedder that spreads grass and the like, a rake that gathers grass and the like, a baler that forms grass and the like into a bale, or the like.

The vehicle body <NUM> has a vehicle body frame <NUM>. As illustrated in <FIG>, the vehicle body frame <NUM> includes a vehicle body frame <NUM> provided on the left side and a vehicle body frame 20R provided on the right side. The vehicle body frame <NUM> and the vehicle body frame 20R each extend forward from the transmission <NUM> and support a lower part of the prime mover <NUM>. The vehicle body frame <NUM> and the vehicle body frame 20R are separated from each other in the vehicle-body width direction. A front end part of the vehicle body frame <NUM> and a front end part of the vehicle body frame 20R are coupled to each other via a front coupling plate 20F. A middle part of the vehicle body frame <NUM> and a middle part of the vehicle body frame 20R are coupled to each other via a middle coupling plate <NUM>. The vehicle body frame <NUM> and the vehicle body frame 20R support a front axle case <NUM>. A front axle <NUM> (see <FIG>), which rotatably supports the front wheels 7F, is accommodated in the front axle case <NUM>. That is, in the present embodiment, the vehicle body frame <NUM> is a front axle frame that supports the front axle <NUM>. The vehicle body frame <NUM> may be a frame that supports a structure other than the front axle case <NUM> (a frame other than the front axle frame).

As illustrated in <FIG>, a hood <NUM> is provided upward of the vehicle body frame <NUM>. The hood <NUM> extends in the front-back direction along the vehicle body frame <NUM>. The hood <NUM> is disposed forward of a middle part of the protector <NUM> in the width direction. The hood <NUM> has a left side wall <NUM> provided on the left side, a right side wall 25R provided on the right side, and an upper wall portion 25U that couples upper parts of the left side wall <NUM> and the right side wall 25R. An engine room is formed by the left side wall <NUM>, the right side wall 25R, and the upper wall portion 25U; and the prime mover <NUM>, a cooling fan, a radiator, a battery, and the like are accommodated in the engine room. The front wheels 7F are respectively disposed leftward of the left side wall <NUM> and rightward of the right side wall 25R.

A weight <NUM> is provided forward of the hood <NUM>, that is, forward of the vehicle body frames <NUM> and 20R. The weight <NUM> is attached to a weight bracket (weight attachment portion) <NUM> provided in a front part of the vehicle body <NUM>. The weight bracket <NUM> is attached to the front coupling plate 20F of the vehicle body frame <NUM> by using a fastener such as a bolt. The periphery of the weight <NUM> is covered by a weight cover <NUM>.

As illustrated in <FIG>, the tractor <NUM> includes a steering device <NUM>. The steering device <NUM> has a steering wheel 11a, a rotary shaft (steering shaft) 11b that rotates as the steering wheel 11a rotates, and an assist mechanism (power steering mechanism) 11c that assists in steering of the steering wheel 11a. The assist mechanism 11c includes a hydraulic pump <NUM>, a control valve <NUM> to which a hydraulic fluid delivered from the hydraulic pump <NUM> is supplied, and a steering cylinder <NUM> that is activated by the control valve <NUM>. The control valve <NUM> is a solenoid valve that is activated based on a control signal. The control valve <NUM> is, for example, a three-position switching valve that is switchable by movement of a spool or the like. The control valve <NUM> is switchable also by steering of the steering shaft 11b. The steering cylinder <NUM> is connected to arms (knuckle arms) <NUM> that change the orientation of the front wheels 7F.

Accordingly, when the steering wheel 11a is operated, the switching position and the opening of the control valve <NUM> are switched in accordance with the steering wheel 11a, the steering cylinder <NUM> extends leftward or rightward in accordance with the switching position and the opening of the control valve <NUM>, and thus the steering direction of the front wheels 7F can be changed. The steering device <NUM> described above is an example, and the configuration of the steering device <NUM> is not limited to the configuration described above.

Hereafter, a position detector and a controller will be described. As illustrated in <FIG> and <FIG>, the tractor <NUM> includes a position detector <NUM>. The position detector <NUM> is attached to a front part of the top panel of the protector <NUM> via a mounter <NUM>. However, the attachment position of the position detector <NUM> is not limited to the position illustrated in the figures, and the position detector <NUM> may be attached onto the top panel of the protector <NUM> or may be attached to another part of the vehicle body <NUM>. The position detector <NUM> may be attached to the aforementioned working device, such as a cultivator.

The position detector <NUM> is a device that detects the position thereof (measured position including latitude and longitude) by using a satellite positioning system. That is, the position detector <NUM> receives signals (positions of positioning satellites, transmission time, correction information, and the like) transmitted from the positioning satellites, and detects the position (latitude, longitude) based on the received signals. The position detector <NUM> may detect, as the position (latitude, longitude) thereof, a corrected position that is corrected based on a correction signal and the like from a base station (reference station) that can receive signals from the positioning satellites. Alternatively, the position detector <NUM> may have an inertial measurement unit such as a gyroscope sensor or an acceleration sensor, and may detect, as the position thereof, a position corrected by the inertial measurement unit. With the position detector <NUM>, it is possible to detect the position (travel position) of the vehicle body <NUM> of the tractor <NUM>.

Hereafter, a controller and a display will be described. As illustrated in <FIG>, the tractor <NUM> includes a controller <NUM> and a display <NUM>. The controller <NUM> includes a CPU, an electric circuit, an electronic circuit, and the like, and controls the tractor <NUM> in various ways. The display <NUM> has a liquid crystal panel, an organic EL panel, or the like, and displays information about various types.

A state detector <NUM>, which detects a driving state and the like of the tractor <NUM>, and an ignition switch <NUM> are connected to the controller <NUM>.

The state detector <NUM> is, for example, a device that detects a state of a travel system or the like, and detects, for example, states of a crank sensor, a cam sensor, an engine rotation sensor, an accelerator sensor, a vehicle speed sensor, a steering angle sensor, the position detector <NUM>, and the like. The state detector <NUM> may be a device that detects a state of a portion other than the travel system, such as elevation lever detection sensor, a PTO rotation detection sensor, or the like.

The ignition switch <NUM> is a switch that is set around the operator's seat <NUM> and that an operator can operate. The ignition switch <NUM> is a switch that is switchable between ON and OFF. When the ignition switch <NUM> is ON, the prime mover <NUM> is driven, and, when the ignition switch <NUM> is OFF, the prime mover <NUM> is stopped being driven. The ignition switch <NUM> may include an accessory switch for supplying electric power to electric components. In this case, the ignition switch <NUM> is switchable between a first ON-position for driving the prime mover <NUM>, a second ON-position for supplying electric power to electric components, and an OFF-position.

A seat-occupation detector <NUM> is connected to the controller <NUM>. The seat-occupation detector <NUM> is a device for detecting whether or not the operator's seat <NUM> is occupied. The seat-occupation detector <NUM> is a pressure sensor or a vibration sensor that is set in a seat portion or a backrest of the operator's seat <NUM>, a camera that is set around the operator's seat <NUM>, or the like. When the seat-occupation detector <NUM> is a pressure sensor or a vibration sensor, the seat-occupation detector <NUM> detects that the operator's seat <NUM> is occupied if a pressure (vibration) of a predetermined magnitude or more is detected, and the seat-occupation detector <NUM> detects that the operator's seat <NUM> is not occupied if a pressure (vibration) of less than a predetermined magnitude is detected. When the seat-occupation detector <NUM> is a camera, the seat-occupation detector <NUM> detects that the operator's seat is occupied if the camera detects a person on the operator's seat <NUM>, and the seat-occupation detector <NUM> detects that the operator's seat <NUM> is not occupied if the camera does not detect a person on the operator's seat <NUM>. The seat-occupation detector <NUM> is an example and is not limited.

The controller <NUM> performs control of the travel system of the tractor <NUM> and control of the working system of the tractor <NUM>. The controller <NUM> controls, for example, the engine rotation speed, the vehicle speed, the steering angle of the steering device <NUM>, and the like based on a detection state detected by the state detector <NUM>. The controller <NUM> performs control of autonomous travel based on a detection state detected by the state detector <NUM>. To be specific, the controller <NUM> includes an autonomous travel controller 40A. The autonomous travel controller 40A includes an electric/electronic circuit provided in the controller <NUM>, a program stored in the controller <NUM>, and the like.

In performing autonomous travel, as illustrated in <FIG>, a travel route (planned travel route) L1 is created by using the display <NUM> and the like. First, creation of the planned travel route L1 will be described.

As illustrated in <FIG>, when an operator or the like performs a predetermined operation on the display <NUM>, the display <NUM> displays a creation screen M1 for creating the planned travel route L1. For example, when an operator or the like inputs a predetermined agricultural field name to an agricultural-field input portion <NUM> of the creation screen M1, the display <NUM> displays on the creation screen M1 an agricultural field map (agricultural field map MP2) input to the agricultural-field input portion <NUM>. By performing a predetermined operation on the display <NUM>, it is possible to create a travel route (planned travel route) L1 of the vehicle body <NUM> on the agricultural field map MP2. In creating the planned travel route L1, for example, in the agricultural field map MP2, it is possible to create straight movement portions L1a representing straight movements and turning portions L1b representing turns, as the planned travel route L1. The distances between the straight movement portions L1a in the width direction, the number of the straight movement portions L1a, and the like may be set in any appropriate manner. That is, with the display <NUM>, it is possible to set (create) the planned travel route L1 for performing autonomous travel in the agricultural field H1. A planned travel route L1 created by using an external apparatus such as a server may be acquired by the tractor <NUM> and displayed on the display <NUM>.

When creation of the planned travel route L1 is complete and a command to start autonomous travel is issued, the autonomous travel controller 40A performs control of autonomous travel (autonomous travel control). As illustrated in <FIG>, a command to start autonomous travel may be issued by using a remote control <NUM> for performing remote control, or by using a switch <NUM> that is set around the operator's seat or the like of the tractor <NUM>.

In autonomous travel control, the autonomous travel controller 40A sets the switching position and the opening of the control valve <NUM> so that at least the travel position (position detected by the position detector <NUM>) of the vehicle body <NUM> coincides with a predetermined travel route (travel path), that is, so that the vehicle body <NUM> coincides with the planned travel route L1. In other words, the controller <NUM> sets the movement direction and the movement distance of the steering cylinder <NUM> (the steering direction and the steering angle of the front wheels 7F) so that the travel position of the tractor <NUM> coincides with the planned travel route L1.

To be specific, the autonomous travel controller 40A compares the travel position of the vehicle body <NUM> with a position indicated by the planned travel route L1 (planned travel position). When the travel position coincides with the planned travel position, the autonomous travel controller 40A does not change and holds the steering angle and steering direction of the steering wheel 11a of the steering device <NUM> (the steering angle and the steering direction of the front wheels 7F) (does not change and maintains the opening and the switching position of the control valve <NUM>). When the travel position does not coincide with the planned travel position, the autonomous travel controller 40A changes the steering angle and/or the steering direction of the steering wheel 11a of the steering device <NUM> (changes the opening and/or the switching position of the control valve <NUM>) so that the difference (displacement) between the travel position and the planned travel position becomes zero.

In the embodiment described above, in autonomous travel control, the autonomous travel controller 40A changes the steering angle of the steering device <NUM> based on the difference between the travel position and the planned travel position. If the orientation of the planned travel route L1 differs from the orientation (vehicle-body orientation) of the movement direction (travel direction) of the tractor <NUM> (the vehicle body <NUM>), the autonomous travel controller 40A may set the steering angle so that the vehicle-body orientation coincides with the orientation of the planned travel route L1. In autonomous travel control, the autonomous travel controller 40A may set the final steering angle in autonomous travel control based on a steering angle obtained based on the difference (positional deviation) and a steering angle obtained based on an orientational deviation. The steering angle may be set by using a method different from the aforementioned method of setting the steering angle in autonomous travel control.

In autonomous travel control, the autonomous travel controller 40A may control the rotation speed of the travel device <NUM>, that is, the front wheels 7F and/or the rear wheels 7R so that the actual vehicle speed of the tractor <NUM> (the vehicle body <NUM>) coincides with a vehicle speed corresponding to a predetermined planned travel route L1.

The autonomous travel controller 40A controls autonomous travel based on the detection result of detecting an obstacle by an obstacle detector <NUM>. For example, the autonomous travel controller 40A continues autonomous travel when the obstacle detector <NUM> is not detecting an obstacle, and stops autonomous travel when the obstacle detector <NUM> detects an obstacle. To be more specific, when the obstacle detector <NUM> detects an obstacle, the autonomous travel controller 40A stops autonomous travel by stopping travel of the tractor <NUM> if the distance between the obstacle and the tractor <NUM> is less than or equal to a predetermined threshold (stop threshold).

During autonomous travel, the autonomous travel controller 40A continues autonomous travel when the seat-occupation detector <NUM> is detecting that the operator's seat is occupied and stops autonomous travel when the seat-occupation detector <NUM> detects that the operator's seat is not occupied.

As illustrated in <FIG>, during autonomous travel (when autonomous travel is being performed), a figure G1 representing the tractor <NUM> (the vehicle body <NUM>) and the planned travel route L1 are displayed on the display <NUM>.

Hereafter, details of the obstacle detector will be described. As illustrated in <FIG>, the tractor <NUM> includes a plurality of obstacle detectors <NUM>. Each of the plurality of obstacle detectors <NUM> can detect an object, that is, an obstacle that is present around the tractor <NUM>. At least one of the plurality of obstacle detectors <NUM> is provided forward of the protector <NUM> and outward of the hood <NUM>. That is, at least one obstacle detector <NUM> is disposed, in a region forward of the protector <NUM> of the tractor <NUM>, in a region further leftward than the left side wall <NUM> of the hood <NUM> or a region further rightward than the right side wall 25R of the hood <NUM>. In the present embodiment, the plurality of obstacle detectors <NUM> include an obstacle detector <NUM> provided on the left side of the vehicle body <NUM> (on the left side of the hood <NUM>) and an obstacle detector 45R provided on the right side of the vehicle body <NUM> (the right side of the hood <NUM>).

The obstacle detectors <NUM> are provided forward of the front wheels 7F and further outward than the front wheels 7F. The obstacle detector <NUM> is provided forward of the left front wheel 7F and further outward (leftward) than the left front wheel <NUM>. The obstacle detector 45R is provided forward of the right front wheel 7F and further outward (rightward) than the right front wheel 7F. In other words, the obstacle detector <NUM> is provided leftward and forward of the left front wheel 7F, and the obstacle detector 45R is provided rightward and forward of the right front wheel 7F.

The obstacle detector <NUM> is a laser scanner 45A, a sonar 45B, and the like. The laser scanner 45A detects an object (obstacle) by emitting laser light as a detection wave. The laser scanner 45A detects the distance to an obstacle based on the time from emission to receipt of laser light. As illustrated in <FIG> and <FIG>, the laser scanner 45A includes a light emitter/receiver 45A1 and a housing 45A2. The light emitter/receiver 45A1 emits laser light and receives the emitted laser light reflected by an obstacle (reflected light). That is, the light emitter/receiver 45A1 includes an emission portion that emits laser light (detection wave) and a receiving portion that receives the laser light (detection wave) reflected by an obstacle. The housing 45A2 is a case that accommodates and holds the light emitter/receiver 45A1. The housing 45A2 includes an upper body 45A3 disposed upward of the light emitter/receiver 45A1 and a lower body 45A4 disposed downward of the light emitter/receiver 45A1. All or part of the space between the upper body 45A3 and the lower body 45A4, that is, the periphery of the light emitter/receiver 45A1 is open, and laser light (detection wave) can pass therethrough.

The sonar 45B detects an object (obstacle) by emitting a sound wave as a detection wave. As illustrated in <FIG> and <FIG>, the sonar 45B includes a sound emitter/receiver 45B1 and a housing 45B2. The sound emitter/receiver 45B1 emits a sound wave and receives the emitted sound wave reflected by an obstacle. That is, the sound emitter/receiver 45B1 includes an emission portion that emits a sound wave (detection wave) and a receiving portion that receives the sound wave (detection wave) reflected by an obstacle. The housing 45B2 is a case that accommodates and holds the sound emitter/receiver 45B1. The sonar 45B detects the distance to an obstacle based on the time from emission to receipt of a sound wave.

As illustrated in <FIG>, the laser scanner 45A and the sonar 45B are disposed forward of the front wheel 7F and outward of the front wheel 7F. To be more specific, at least the receiving portions (the light emitter/receiver 45A1 and the sound emitter/receiver 45B1) of the laser scanner 45A and the sonar 45B are disposed forward of the front wheel 7F and outward of the front wheel 7F.

As illustrated in <FIG>, the laser scanner 45A and the sonar 45B are set at positions that are further downward than the upper wall portion 25U of the hood <NUM> and lower than an upper end part of the front wheel 7F. Therefore, the light emitter/receiver 45A1 of the laser scanner 45A and the sound emitter/receiver 45B1 of the sonar 45B are also set at positions that are further downward than the upper wall portion 25U of the hood <NUM> and are lower than the upper end part of the front wheel 7F. The laser scanner 45A (the light emitter/receiver 45A1) and the sonar 45B (the sound emitter/receiver 45B1) are positioned further downward than the upper end part the front wheel 7F and further upward than the front axle <NUM>.

As illustrated in <FIG> and <FIG>, the laser scanner 45A is disposed further outward than the sonar 45B. To be specific, as illustrated in <FIG>, in a state in which the front wheel 7F is positioned to move the vehicle body <NUM> straight (a state in which the steering wheel 11a is not steered), the laser scanner 45A (the light emitter/receiver 45A1) is disposed further outward than an imaginary line X1 that is positioned outward by the width of the front wheel 7F (tread width) from an outer end of the front wheel 7F in the width direction. The sonar 45B is disposed further inward than the imaginary line X1.

As illustrated in <FIG>, the obstacle detector <NUM> is supported by the vehicle body <NUM> via a support <NUM>. The support <NUM> can change the position of the obstacle detector <NUM> to a detection position (see <FIG> and <FIG>) and to a retracted position (see <FIG> and <FIG>). The support <NUM> includes a support <NUM> that supports the obstacle detector <NUM> leftward of the vehicle body <NUM> and a support 50R that supports the obstacle detector <NUM> rightward of the vehicle body <NUM>. The support <NUM> and the support 50R have the same configuration except that they are symmetric to each other about a center line CL1 in the vehicle-body width direction.

The support <NUM> extends outward from the vehicle body frame (front axle frame) <NUM>. To be specific, the support <NUM> extends leftward from the vehicle body frame <NUM>. The support 50R extends rightward from the vehicle body frame 20R.

As illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, the support <NUM> has a first support portion 50A, a second support portion 50B, and a third support portion 50C.

The first support portion 50A has an attachment arm <NUM>, an attachment plate <NUM>, a front support plate <NUM>, and a back support plate <NUM>. The attachment arm <NUM> extends forward and outward from a front side part of the vehicle body frame <NUM>. The attachment arm <NUM> includes an attachment arm <NUM> and an attachment arm 51R. The attachment arm <NUM> is attached to a front part of a left side surface of the vehicle body frame <NUM>, and extends leftward and forward from the front part. The attachment arm 51R is attached to a front part of a right side surface of the vehicle body frame 20R, and extends rightward and forward from the front part. The attachment plate <NUM> is attached to a front end part of each of the attachment arms <NUM> and 51R, and one surface thereof faces outward and the other surface thereof faces inward. The attachment plate <NUM> on the left side, which is attached to the attachment arm <NUM>, and the attachment plate <NUM> on the right side, which is attached to the attachment arm 51R, are coupled via a coupling <NUM>. The coupling <NUM> is formed from a pipe, extends through a space above the weight cover <NUM>, and couples an upper part of the attachment plate <NUM> on the left side and an upper part of the attachment plate <NUM> on the right side.

The front support plate <NUM> and the back support plate <NUM> have the same shape, and are disposed parallel to each other and so as to face each other with a distance therebetween in the front-back direction. The front support plate <NUM> and the back support plate <NUM> are attached to one surface of the attachment plate <NUM> and extend outward. As illustrated in <FIG>, a lower support plate <NUM> is in contact with a lower edge of the front support plate <NUM> and a lower edge of the back support plate <NUM>. An upper support plate <NUM> is in contact with an upper edge of the front support plate <NUM> and an upper edge of the back support plate <NUM>. The lower support plate <NUM> and the upper support plate <NUM> are fixed to the attachment plate <NUM>. In <FIG>, the front support plate <NUM> is shown by an imaginary line.

As illustrated in <FIG> and <FIG>, a first front hole 53a and a second front hole 53b are formed in the front support plate <NUM>. A first back hole 54a and a second back hole 54b are formed the back support plate <NUM>. The first back hole 54a is at a position facing the first front hole 53a, and the second back hole 54b is at a position facing the second front hole 53b. As illustrated in <FIG>, <FIG>, and <FIG>, a tubular body <NUM> and a receiver <NUM> are fixed to an upper part of the back support plate <NUM>. The tubular body <NUM> has a central hole whose axial direction extends in the front-back direction. The axis of the central hole of the tubular body <NUM> and the center of the second back hole 54b are disposed on the same straight line. The receiver <NUM> is fixed to a lower part of the front support plate <NUM> and a lower part of the back support plate <NUM>. The receiver <NUM> is a U-shaped member, and has a front portion 59a fixed to a front surface of the front support plate <NUM>, a back portion 59b fixed to a back surface of the back support plate <NUM>, and a lower portion 59c connecting the front portion 59a and the back portion 59b. A knob bolt <NUM> is screwed into the lower portion 59c of the receiver <NUM>. The axis of the threaded shaft of the knob bolt <NUM> is oriented in the up-down direction. As illustrated in <FIG>, a distal end member <NUM> is attached to the threaded shaft of the knob bolt <NUM>. The position (height) of the distal end member <NUM> can be adjusted by rotating the knob bolt <NUM>.

As illustrated in <FIG>, <FIG>, <FIG>, and other figures, the second support portion 50B is supported between the front support plate <NUM> and the back support plate <NUM>. The second support portion 50B has a one-side plate <NUM>, an other-side plate <NUM>, a coupling plate <NUM>, and a support arm <NUM>.

The one-side plate <NUM> and the other-side plate <NUM> have the same shape, and are disposed parallel to each other and so as to face each other with a distance therebetween in the front-back direction. The one-side plate <NUM> faces the front support plate <NUM>, and the other-side plate <NUM> faces the back support plate <NUM>. As illustrated in <FIG>, a first one-side hole 65a, a second one-side hole 65b, and a third one-side hole 65c are formed in the one-side plate <NUM>. As illustrated in <FIG> and <FIG>, a first other-side hole 66a, a second other-side hole 66b, and a third other-side hole 66c are formed in the other-side plate <NUM>. The first other-side hole 66a is at a position facing the first one-side hole 65a. The second other-side hole 66b is at a position facing the second one-side hole 65b. The third other-side hole 66c is at a position facing the third one-side hole 65c. In <FIG>, the front support plate <NUM> and the one-side plate <NUM> are omitted. The coupling plate <NUM> is a strip-shaped plate bent into an L-shape, and couples the one-side plate <NUM> and the other-side plate <NUM>.

As illustrated in <FIG> and <FIG>, a cylindrical boss <NUM> is fitted into the first one-side hole 65a and the first other-side hole 66a. To be specific, a front end portion of the boss <NUM> is fitted into the first one-side hole 65a, and the back end portion of the boss <NUM> is fitted into the first other-side hole 66a. A central hole 68a of the boss <NUM>, the first front hole 53a, and the first back hole 54a are disposed on the same straight line, and a threaded shaft of a bolt BL1 (see <FIG> and <FIG>) is inserted so as to extend through these holes. A nut NT1 is screwed onto the threaded shaft of the bolt BL1. With the bolt BL1 and the nut NT1, the second support portion 50B (the one-side plate <NUM>, the other-side plate <NUM>, the coupling plate <NUM>) is interposed and supported between the front support plate <NUM> and the back support plate <NUM>. The second support portion 50B is rotatable relative to the first support portion 50A with the threaded shaft of the bolt BL1 as a supporting point. In other words, the threaded shaft of the bolt BL1 functions as a support shaft that rotatably supports the second support portion 50B.

As illustrated in <FIG> and <FIG>, a first contact member <NUM> and a second contact member <NUM> are fixed between the one-side plate <NUM> and the other-side plate <NUM>. The first contact member <NUM> and the second contact member <NUM> are disposed on the same circle that is centered on a support shaft (the threaded shaft of the bolt BL1). That is, the first contact member <NUM> and the second contact member <NUM> are equidistant from the support shaft (the threaded shaft of the bolt BL1). The first contact member <NUM> and the second contact member <NUM> are disposed at positions that are separated by <NUM>° around the support shaft (the threaded shaft of the bolt BL1).

As illustrated in <FIG> and <FIG>, the support arm <NUM> extends from the first support portion 50A outward of the vehicle body. One end portion of the support arm <NUM> and an abutting member <NUM> described below are connected to the coupling plate <NUM>. The third support portion 50C is connected to the other end portion of the support arm <NUM>.

The third support portion 50C supports the obstacle detector <NUM>. As illustrated in <FIG> and <FIG> and other figures, the third support portion 50C has a support bracket <NUM> and a support stay <NUM>. The support bracket <NUM> supports the laser scanner 45A. The support bracket <NUM> is a substantially C-shaped member including an upper horizontal portion 75a, a lower horizontal portion 75b, and a vertical portion 75c. The vertical portion 75c is fixed to the other end portion of the support arm <NUM>. The upper horizontal portion 75a supports the upper body 45A3 of the housing 45A2. The lower horizontal portion 75b supports the lower body 45A4 of the housing 45A2. Thus, the laser scanner 45A is supported by the support bracket <NUM>. The support stay <NUM> is fixed to a middle part of the support arm <NUM> and supports the sonar 45B. The sonar 45B is attached to the support stay <NUM> so that the sound emitter/receiver 45B1 faces forward and inward of the vehicle body.

The attachment plate <NUM>, the front support plate <NUM>, the back support plate <NUM> (see <FIG> and other figures), and the like of the first support portion 50A described above are included in a position changing mechanism <NUM> that changes the position of the obstacle detector <NUM>. The position changing mechanism <NUM> is a mechanism that changes the position of the obstacle detector <NUM> to a detection position that is a predetermined position for detecting an obstacle and to a retracted position that is retracted from the detection position toward the vehicle body <NUM>. The position changing mechanism <NUM>, together with the second support portion 50B and the third support portion 50C of the support <NUM>, can change the position of the obstacle detector <NUM>.

<FIG> and <FIG> illustrate a state in which the obstacle detector <NUM> is in the detection position. <FIG> and <FIG> illustrate a state in which the obstacle detector <NUM> is in the retracted position. The change in the position of the obstacle detector <NUM> between the detection position and retracted position can be performed by rotating the second support portion 50B relative to the first support portion 50A with the threaded shaft of the bolt BL1 (support shaft) as a supporting point.

As illustrated in <FIG>, when the obstacle detector <NUM> is in the detection position, the support arm <NUM> extends in a horizontal direction. To be specific, the support arm <NUM> of the support <NUM>, which supports the obstacle detector <NUM> leftward of the vehicle body <NUM>, extends horizontally leftward. The support arm <NUM> of the support 50R, which supports the obstacle detector <NUM> rightward of the vehicle body <NUM>, extends horizontally rightward. When the obstacle detector <NUM> is in the detection position, the emission direction of laser light emitted from the light emitter/receiver 45A1 is the horizontal direction.

When the obstacle detector <NUM> is in the detection position, as illustrated in <FIG>, the second front hole 53b, the second one-side hole 65b, the second other-side hole 66b, and the second back hole 54b are disposed on the same straight line, and a pin <NUM> is inserted so as to extend through these holes and the tubular body <NUM>. By inserting the pin <NUM> through the second front hole 53b, the second one-side hole 65b, the second other-side hole 66b, and the second back hole 54b, the second support portion 50B (the one-side plate <NUM>, the other-side plate <NUM>, the coupling plate <NUM>, the support arm <NUM>) becomes non-rotatable relative to the front support plate <NUM> and the back support plate <NUM>, and the position of the second support portion 50B is fixed. As a result, as illustrated in <FIG>, <FIG>, and <FIG>, the support arm <NUM> is positioned relative to the vehicle body <NUM> in a state of extending in a horizontal direction (detection posture), and the obstacle detector <NUM> is held in the detection position. At this time, the distal end member <NUM>, which is attached to the threaded shaft of the knob bolt <NUM>, is in contact with the first contact member <NUM>.

To change the position of the obstacle detector <NUM> from the detection position (see <FIG>) to the retracted position (see <FIG>), first, the pin <NUM> is pulled out from the holes. The pin <NUM> can be pulled out by gripping a grip portion 64a provided at an end portion of the pin <NUM>. By pulling out the pin <NUM> from the holes, the second support portion 50B (the one-side plate <NUM>, the other-side plate <NUM>, the coupling plate <NUM>, the support arm <NUM>) becomes rotatable relative to the front support plate <NUM> and the back support plate <NUM>. At this time, because the distal end member <NUM> is in contact with the first contact member <NUM>, the second support portion 50B cannot rotate downward and can rotate only upward.

After pulling out the pin <NUM> from the holes, when an upward force is applied to the support arm <NUM>, the second support portion 50B (the one-side plate <NUM>, the other-side plate <NUM>, the coupling plate <NUM>, the support arm <NUM>) rotates upward with the support shaft (the threaded shaft of the bolt BL1) as a supporting point (see arrow U1 in <FIG>). The upward rotational range of the support arm <NUM> is defined by the abutting member <NUM> and a protruding shaft <NUM> (see <FIG> and <FIG>). The abutting member <NUM> is fixed to an upper part of the support arm <NUM>. The protruding shaft <NUM> protrudes outward from a shaft supporter <NUM> disposed on an upper part of the upper support plate <NUM>.

As illustrated in <FIG>, the support arm <NUM> can be rotated upward until the abutting member <NUM> comes into contact with the protruding shaft <NUM>. When the abutting member <NUM> is in contact with the protruding shaft <NUM>, the support arm <NUM> is in a state of extending upward (retracted position). In a state illustrated in <FIG>, the second front hole 53b, the second back hole 54b, the third one-side hole 65c, and the third other-side hole 66c are disposed on the same straight line. Therefore, by inserting the pin <NUM> through these holes and the tubular body <NUM>, the second support portion 50B (the one-side plate <NUM>, the other-side plate <NUM>, the coupling plate <NUM>, the support arm <NUM>) becomes non-rotatable relative to the front support plate <NUM> and the back support plate <NUM>, and the position of the second support portion 50B is fixed. As a result, as illustrated in <FIG> and <FIG>, the support arm <NUM> is positioned relative to the vehicle body <NUM> in a state of extending upward, and the obstacle detector <NUM> is held in the retracted position. At this time, the distal end member <NUM>, which is attached to the threaded shaft of the knob bolt <NUM>, is in contact with the second contact member <NUM>.

As described above, with the position changing mechanism <NUM>, it is possible to change the position of the obstacle detector <NUM> to the detection position and to the retracted position. When in the detection position, the obstacle detector <NUM> can detect an obstacle around the vehicle body <NUM>. When the obstacle detector <NUM> is not to be used, the obstacle detector <NUM> is moved from the detection position to the retracted position.

The position changing mechanism <NUM> has a posture detector for detecting whether the support arm <NUM> is in the detection position or in the retracted position. As the posture detector, for example, a detector that detects the retracted position when the abutting member <NUM> in contact with the protruding shaft <NUM> and detects the detection position when the abutting member <NUM> is separated from the protruding shaft <NUM> is used. The detection information of the posture detector is input to the controller <NUM>.

Hereafter, an effective mode and an ineffective mode will be described. In autonomous travel of the tractor <NUM>, when the obstacle detector <NUM> detects an obstacle, the autonomous travel controller 40A stops the vehicle body <NUM> based on detection information about the obstacle detected by the obstacle detector. During autonomous travel in the agricultural field H1, it is possible to switch between an effective mode in which stopping of the vehicle body <NUM> is performed based on the detection information and an ineffective mode in which stopping of the vehicle body <NUM> is not performed.

In the effective mode, when autonomous travel is being performed, if the obstacle detector <NUM> detects an obstacle and the detected detection information indicates that the distance between the obstacle and the vehicle body <NUM> is less than or equal to a predetermined distance, the vehicle body <NUM> is stopped. On the other hand, in the ineffective mode, when autonomous travel is being performed, even if the obstacle detector <NUM> detects an obstacle and the detected detection information indicates that the distance between the obstacle and the vehicle body <NUM> is less than or equal to a predetermined distance, the vehicle body <NUM> is not stopped and autonomous travel is continued. Alternatively, in the ineffective mode, when autonomous travel is being performed, even if the obstacle detector <NUM> detects an obstacle, the detection of the obstacle (detection information) is not output to the autonomous travel controller 40A, and thus stopping of the vehicle body <NUM> by the autonomous travel controller 40A is not performed. Further alternatively, in the ineffective mode, when autonomous travel is being performed, the obstacle detector <NUM> stops detection of an obstacle, and thus stopping of the vehicle body <NUM> is not performed. That is, in the ineffective mode, in autonomous travel in the agricultural field H1, stopping of the vehicle body <NUM> based on detection information of the obstacle detector <NUM> is not performed irrespective of whether or not an obstacle is detected.

The controller <NUM> includes a mode switcher 40B. The mode switcher 40B includes an electric/electronic circuit provided in the controller <NUM>, a program stored in the controller <NUM>, and the like. As illustrated in <FIG>, when an operator performs a predetermined operation on the display <NUM>, the mode switcher 40B displays a setting screen M2. The setting screen M2 displays a first selecting portion <NUM> for selecting the effective mode and a second selecting portion <NUM> for selecting the ineffective mode. Selection between the first selecting portion <NUM> and the second selecting portion <NUM> can be performed by using an operation member provided in the display <NUM> or an operation member provided around the operator's seat <NUM>. The mode switcher 40B switches to the effective mode when the first selecting portion <NUM> is selected, and switches to the ineffective mode when the second selecting portion <NUM> is selected.

To be more specific, when the ignition switch <NUM> is OFF or in a state in which the ignition switch <NUM> is switched from OFF to ON, the mode switcher 40B sets the effective mode as a default. In the default state (initial state), the display <NUM> displays on the setting screen M2 a state in which the first selecting portion <NUM> is selected. That is, in a state in which driving of the prime mover <NUM> is stopped or in a state in which the prime mover <NUM> is restarted after stopped being driven, the mode switcher 40B sets the effective mode as a default.

On the other hand, after driving the prime mover <NUM>, when switching from the effective mode to the ineffective mode is performed on the setting screen M2, and if driving of the prime mover <NUM> is stopped, the mode switcher 40B switches from the ineffective mode to the effective mode. That is, in a state in which the ignition switch <NUM> is switched from ON to OFF in a state in which the ineffective mode is maintained, the mode switcher 40B switches to the effective mode.

In the embodiment described above, the mode switcher 40B performs switching between the effective mode and the ineffective mode in accordance with an operation on the setting screen M2 displayed on the display <NUM>. However, switching between the modes may be restrained.

The controller <NUM> includes a switching restrainer 40C. The switching restrainer 40C includes an electric/electronic circuit provided in the controller <NUM>, a program stored in the controller <NUM>, and the like. When the obstacle detector <NUM> is in the retracted position, the switching restrainer 40C allows the mode switcher 40B to switch from the effective mode to the ineffective mode. For example, in a state in which the setting screen M2 is displayed on the display <NUM>, when the obstacle detector <NUM> is in the retracted position, the switching restrainer 40C allows (permits) the mode switcher 40B to switch from the effective mode to the ineffective mode due to selection of the second selecting portion <NUM>.

On the other hand, in a state in which the setting screen M2 is displayed on the display <NUM>, when the obstacle detector <NUM> is in the detection position, the switching restrainer 40C does not allow (permit) the mode switcher 40B to switch from the effective mode to the ineffective mode due to selection of the second selecting portion <NUM>. That is, when the obstacle detector <NUM> is in the retracted position, the switching restrainer 40C does not permit the mode switcher 40B to accept selection of the second selecting portion <NUM>.

In the embodiment described above, if the obstacle detector <NUM> is in the detection position, the switching restrainer 40C does not allow switching from the effective mode to the ineffective mode. Instead, restraint of the ineffective mode may be performed based on whether or not the operator's seat is occupied by an operator.

To be specific, the controller <NUM> includes a switching restrainer 40D. The switching restrainer 40D includes an electric/electronic circuit provided in the controller <NUM>, a program stored in the controller <NUM>, and the like.

When the seat-occupation detector <NUM> is detecting that the operator's seat is occupied, the switching restrainer 40D allows the mode switcher 40B to switch from the effective mode to the ineffective mode. For example, in a state in which the setting screen M2 is displayed on the display <NUM>, when the operator's seat is occupied by an operator, the switching restrainer 40D allows (permits) the mode switcher 40B to switch from the effective mode to the ineffective mode due to selection of the second selecting portion <NUM>.

On the other hand, in a state in which the setting screen M2 is displayed on the display <NUM>, when the seat-occupation detector <NUM> is detecting that the operator's seat is not occupied, the switching restrainer 40D does not allow the mode switcher 40B to switch from the effective mode to the ineffective mode due to selection of the second selecting portion <NUM>. That is, when the operator's seat <NUM> is not occupied by an operator, the switching restrainer 40D does not allow the mode switcher 40B to accept selection of the second selecting portion <NUM>.

Hereafter, a first example of an autonomous travel flow will be described. <FIG> illustrates an operation flow of autonomous travel. In <FIG>, it is assumed that autonomous travel is not performed immediately after the ignition switch <NUM> is turned ON. <FIG> is an operation flow of autonomous travel in the ineffective mode.

As illustrated in <FIG>, the mode switcher 40B determines whether or not the ignition switch <NUM> is ON (S <NUM>). For example, if the ignition switch <NUM> is ON (if the prime mover <NUM> is being driven or electric power is being supplied to electric components) (S <NUM>, Yes), the mode switcher 40B sets to the effective mode (S2). When a predetermined operation is performed, the display <NUM> displays the setting screen M2 (S3). The switching restrainer 40C determines whether or not the obstacle detector <NUM> is in the retracted position (S4). If the obstacle detector <NUM> is in the retracted position (S4, Yes), the switching restrainer 40C allows the mode switcher 40B to switch from the effective mode to the ineffective mode on the setting screen M2, and accepts the ineffective mode (S5).

On the other hand, if the obstacle detector <NUM> is not in the retracted position (S4, No), the switching restrainer 40C does not allow the mode switcher 40B to switch from the effective mode to the ineffective mode on the setting screen M2, and does not accept the ineffective mode (S6). In addition, if the obstacle detector <NUM> is not in the retracted position (S4, No), the autonomous travel controller 40A outputs an anomaly (alarm) to the display <NUM>, and the display <NUM> displays on the setting screen M2 or the like an anomaly (alarm) indicating that the obstacle detector <NUM> is not in the retracted position (S7).

After accepting the ineffective mode (in and after S5), the autonomous travel controller 40A waits for acquisition of a start command to start autonomous travel. When a start button of the remote control <NUM>, the switch <NUM>, or the like is pressed and the start command is acquired (S8), the autonomous travel controller 40A determines whether or not the operator's seat is occupied by an operator (S9). If the operator's seat <NUM> is occupied by an operator (S9, Yes), the autonomous travel controller 40A performs autonomous travel control, that is, starts autonomous travel in the ineffective mode (S10).

When autonomous travel is started in the ineffective mode, the autonomous travel controller 40A does not perform stopping of the vehicle body <NUM> due to detection of an obstacle, irrespective of the detection information of the obstacle detector <NUM>. As illustrated in <FIG>, when autonomous travel is being performed in the ineffective mode, the display <NUM> displays in a message portion <NUM> that autonomous travel in the ineffective mode is being performed. The display <NUM> may display in the message portion <NUM> that autonomous travel in the effective mode is being performed.

On the other hand, if the operator's seat is not occupied by an operator (S9, No), the autonomous travel controller 40A outputs an anomaly (alarm) to the display <NUM>, and displays on the display <NUM> an anomaly (alarm) indicating that the operator's seat is not occupied (S11). Before starting autonomous travel and if the operator's seat is not occupied (S8 to S9, when the process proceeds to No), the autonomous travel controller 40A prohibits autonomous travel. On the other hand, when autonomous travel is being performed and the operator's seat is not occupied (S10 to S9, when the process proceeds to No), the autonomous travel controller 40A stops travel of the vehicle body <NUM> (S12). If the operator's seat is occupied when autonomous travel is being performed after starting autonomous travel (S10 to S9, when the process proceeds to Yes), the autonomous travel controller 40A continues autonomous travel.

Hereafter, a second example of an autonomous travel flow will be described. <FIG> illustrates an operation flow of autonomous travel different from that of <FIG>. Also in <FIG>, it is assumed that autonomous travel is not performed immediately after the ignition switch <NUM> is turned ON. <FIG> is an operation flow of autonomous travel in the ineffective mode.

As illustrated in <FIG>, the mode switcher 40B determines whether or not the ignition switch <NUM> is ON (S1). For example, if the ignition switch <NUM> is ON (if the prime mover <NUM> is being driven or electric power is being supplied to electric components) (S1, Yes), the mode switcher 40B sets to the effective mode (S2). When a predetermined operation is performed, the display <NUM> displays the setting screen M2 (S3). The switching restrainer 40D determines whether or not the operator's seat is occupied by an operator (S20). If the operator's seat is occupied by an operator (S20, Yes), the switching restrainer 40D allows the mode switcher 40B to switch from the effective mode to the ineffective mode on the setting screen M2, and accepts the ineffective mode (S21).

On the other hand, if the operator's seat is not occupied by an operator (S20, No), the switching restrainer 40D does not allow the mode switcher 40B to switch from the effective mode to the ineffective mode on the setting screen M2, and does not accept the ineffective mode (S22). In addition, if the operator's seat is not occupied by an operator (S20, No), the autonomous travel controller 40A outputs an anomaly (alarm) to the display <NUM>, and the display <NUM> displays on the setting screen M2 or the like an anomaly (alarm) indicating that the operator's seat is not occupied by an operator (S23). Descriptions of S8 to S12 in 19B, which are similar to those of <FIG>, will be omitted.

In the embodiment described above, switching from the effective mode to the ineffective mode is allowed if the obstacle detector <NUM> is in the retracted position or if the operator's seat is occupied by an operator. However, switching from the effective mode to the ineffective mode may be allowed if the obstacle detector <NUM> is in the retracted position and the operator's seat is occupied by an operator.

Hereafter, a third example of an autonomous travel flow will be described. In the embodiment described above, switching from the effective mode to the ineffective mode is restrained based on the position of the obstacle detector <NUM> (detection position, retracted position) or the state of the operator's seat (occupied, not occupied). However, switching from the effective mode to the ineffective mode may be performed irrespective of the position of the obstacle detector <NUM> and the state of the operator's seat. In addition, whether or not to allow starting of autonomous travel may be set based on the position of the obstacle detector <NUM>. For example, before autonomous travel, when in the ineffective mode, the autonomous travel controller 40A can start autonomous travel if the obstacle detector <NUM> is in the retracted position, and, when in the ineffective mode, the autonomous travel controller 40A does not start autonomous travel if the obstacle detector <NUM> is not in the retracted position.

<FIG> illustrates an operation flow of autonomous travel different from those of <FIG> and <FIG>. Also in <FIG>, it is assumed that autonomous travel is not performed immediately after the ignition switch <NUM> is turned ON. <FIG> is an operation flow of autonomous travel in the ineffective mode.

As illustrated in <FIG>, the mode switcher 40B determines whether or not the ignition switch <NUM> is ON (S <NUM>). For example, if the ignition switch <NUM> is ON (if the prime mover <NUM> is being driven or electric power is being supplied to electric components) (S <NUM>, Yes), the mode switcher 40B sets to the effective mode (S2). When a predetermined operation is performed, the display <NUM> displays the setting screen M2 (S3).

On the setting screen M2, irrespective of the position of the obstacle detector <NUM> and the state of the operator's seat, it is possible to switch between the effective mode and the ineffective mode, that is, it is possible to accept the effective mode or the ineffective mode. If the ineffective mode is set on the setting screen M2 (S50), the autonomous travel controller 40A determines whether or not the obstacle detector <NUM> is in the retracted position (S51). If the obstacle detector <NUM> is not in the retracted position (S51, No), the autonomous travel controller 40A outputs an anomaly (alarm) to the display <NUM>, and the display <NUM> displays on the setting screen M2 or the like an anomaly (alarm) indicating that the obstacle detector <NUM> is not in the retracted position (S52). Descriptions of S8 to S12 in 19C, which are similar to those of <FIG> and <FIG>, will be omitted.

In <FIG> described above, when autonomous travel is being performed (during autonomous travel) in the ineffective mode, the autonomous travel controller 40A continues autonomous travel when in the retracted position, and, on the other hand, stops autonomous travel when changed from the retracted position to the detection position.

Hereafter, autonomous travel in the effective mode will be described. In <FIG> described above, autonomous travel in the ineffective mode has been described. Autonomous travel in the effective mode is as follows.

When set in the effective mode, the autonomous travel controller 40A determines whether or not the obstacle detector <NUM> is in the detection position. The autonomous travel controller 40A starts autonomous travel if the obstacle detector <NUM> is in the detection position and starting of autonomous travel is acquired. In autonomous travel in the effective mode, the autonomous travel controller 40A may start autonomous travel if the following three conditions are satisfied: a condition that the obstacle detector <NUM> is in the detection position, a condition that starting of autonomous travel is acquired, and a condition that the operator's seat is occupied. When the effective mode is set before starting autonomous travel, if the obstacle detector <NUM> is in the retracted position, an anomaly (alarm) indicating that the obstacle detector <NUM> is in the retracted position may be displayed on the display <NUM>.

The agricultural machine <NUM> includes: the vehicle body <NUM> that is capable of traveling; the obstacle detector <NUM> that is capable of detecting an obstacle; the autonomous travel controller 40A that performs autonomous travel of the vehicle body <NUM> and that, when performing the autonomous travel, stops the vehicle body <NUM> based on detection information about an obstacle detected by the obstacle detector <NUM>; and the mode switcher 40B that switches a mode during the autonomous travel in an agricultural field between an effective mode in which the stopping of the vehicle body <NUM> based on the detection information is allowed and an ineffective mode in which the stopping of the vehicle body based on the detection information is not allowed. Thus, because the agricultural machine <NUM> includes the mode switcher 40B, during autonomous travel in the agricultural field, when in the effective mode, it is possible to stop the vehicle body <NUM> based on the detection information detected by the obstacle detector <NUM>. On the other hand, when in the ineffective mode, it is possible to perform autonomous travel without stopping the vehicle body <NUM>, irrespective of the detection information of the obstacle detector <NUM>. That is, on the assumption that autonomous travel is performed in the agricultural field, it is possible to stop detection of an obstacle for stopping the vehicle body <NUM> or it is possible to refrain from stopping of the vehicle body <NUM> even if an obstacle is detected. In other words, whether or not to stop autonomous travel can be changed in accordance with the circumstances.

The agricultural machine <NUM> includes the support <NUM> to which the obstacle detector <NUM> is attached and that is capable of changing the position of the obstacle detector <NUM> to the detection position and to the retracted position, and the autonomous travel controller 40A is allowed to perform the autonomous travel when the autonomous travel controller 40A is in the ineffective mode and the obstacle detector <NUM> is in the retracted position. Thus, when the obstacle detector <NUM> is in the retracted position where the obstacle detector <NUM> cannot physically detect an obstacle or the like, it is possible to perform autonomous travel irrespective of whether or not an obstacle is detected.

The agricultural machine <NUM> includes the seat-occupation detector <NUM> that detects whether or not the operator's seat <NUM> is occupied, and the autonomous travel controller 40A is allowed to start the autonomous travel when the seat-occupation detector <NUM> is detecting that the operator's seat <NUM> is occupied. Thus, during manned autonomous travel, on condition that the operator's seat <NUM> is occupied by an operator, it is possible to perform autonomous travel irrespective of whether or not an obstacle is detected.

The agricultural machine <NUM> includes: the support <NUM> to which the obstacle detector <NUM> is attached and that is capable of changing the position of the obstacle detector <NUM> to the detection position and to the retracted position; and the switching restrainer 40C that allows the mode switcher 40B to switch from the effective mode to the ineffective mode when the obstacle detector <NUM> is in the retracted position, and does not allow the mode switcher 40B to switch from the effective mode to the ineffective mode when the obstacle detector <NUM> is in the detection position. Thus, only when the obstacle detector <NUM> is in the retracted position and in a state in which the obstacle detector <NUM> cannot detect an obstacle (a state of not being in the detection position physically), it is possible to perform switching from the effective mode to the ineffective mode. That is, when an operator intentionally moves the obstacle detector <NUM> to the retracted position, it is possible to change the mode to the ineffective mode and thus to avoid a situation different from the operator's intention.

The agricultural machine <NUM> includes: the seat-occupation detector <NUM> that detects whether the operator's seat is occupied; and the switching restrainer 40D that allows the mode switcher 40B to switch from the effective mode to the ineffective mode when the seat-occupation detector <NUM> is detecting that the operator's seat is occupied and does not allow the mode switcher 40B to switch from the effective mode to the ineffective mode when the seat-occupation detector <NUM> detects that the operator's seat is not occupied. Thus, only when the operator's seat is occupied by an operator and manned autonomous travel is performed, it is possible to perform autonomous travel without stopping the vehicle body <NUM> irrespective of the detection information of the obstacle detector <NUM>.

The agricultural machine <NUM> includes the seat-occupation detector <NUM> that detects whether the operator's seat is occupied, and the autonomous travel controller 40A, when performing the autonomous travel, continues performing the autonomous travel when the seat-occupation detector <NUM> is detecting that the operator's seat is occupied, and stops the autonomous travel when the seat-occupation detector <NUM> detects that the operator's seat is not occupied. Thus, during manned autonomous travel, it is possible to automatically stop autonomous travel when an operator leaves the operator's seat <NUM>, and it is possible to increase the precision of manned autonomous travel.

The agricultural machine <NUM> includes the support <NUM> to which the obstacle detector <NUM> is attached and that is capable of changing the position of the obstacle detector <NUM> to the detection position and to the retracted position, and the autonomous travel controller 40A, when performing the autonomous travel and in the ineffective mode, continues performing the autonomous travel when the obstacle detector <NUM> is in the retracted position, and stops the autonomous travel when the position of the obstacle detector <NUM> changes from the retracted position to the detection position. Thus, during autonomous travel in the ineffective mode, if the position of the obstacle detector <NUM> changes from the retracted position to the detection position for any reason, it is possible to stop autonomous travel and to prevent the obstacle detector <NUM> from colliding with a structure (water supply/drainage equipment) in the agricultural field, crops, and the like in the autonomous travel in the ineffective mode.

The agricultural machine <NUM> includes the prime mover <NUM> and the ignition switch <NUM> that performs switching between ON and OFF of driving of the prime mover <NUM>, and the mode switcher 40B sets the effective mode as a default according to switching of the ignition switch <NUM> from OFF to ON, and, when the ineffective mode is set, switches the ineffective mode to the effective mode according to switching of the ignition switch <NUM> from ON to OFF. Thus, for example, when the ignition switch <NUM> is switched from OFF to ON and the prime mover <NUM> is driven, or when the ignition switch <NUM> is switched from ON to OFF and driving of the prime mover <NUM> is stopped, it is possible to reliably start from the effective mode.

The agricultural machine <NUM> includes the display <NUM> that displays whether the autonomous travel controller is in the effective mode or in the ineffective mode. Thus, it is possible to allow an operator to reliably grasp whether autonomous travel is performed in the effective mode or autonomous travel is performed in the ineffective mode.

The autonomous travel controller 40A stops the vehicle body <NUM> if the autonomous travel controller 40A, when in the effective mode, acquires detection of an obstacle by the obstacle detector <NUM> as the detection information. Thus, it is possible to reliably stop the vehicle body <NUM> when an obstacle is detected during autonomous travel in the effective mode.

the obstacle detector <NUM>, even when detecting the obstacle, does not output detection of the obstacle to the autonomous travel controller 40A when in the ineffective mode. Thus, by not outputting detection of the obstacle to the autonomous travel controller 40A, it is possible to reliably prevent the autonomous travel controller 40A from stopping the vehicle body <NUM> due to detection of the obstacle.

In the ineffective mode, when autonomous travel is being performed, instead of not outputting detection of an obstacle (detection information) to the autonomous travel controller 40A even when detecting the obstacle, the obstacle detector <NUM> may output the detection information to the controller <NUM> other than the autonomous travel controller 40A to store the detection information in the controller <NUM>. In such a case, while detection of an obstacle is not used to stop the vehicle body <NUM>, it is possible to grasp what kind of an object is detected as the obstacle by analyzing the detection information. Moreover, it is possible to grasp the state of the agricultural field by associating the detection information with the position of the vehicle body (travel position).

Claim 1:
An agricultural machine (<NUM>) comprising:
a vehicle body (<NUM>) that is capable of traveling;
an obstacle detector (<NUM>) that is capable of detecting an obstacle;
an autonomous travel controller (40a) that performs autonomous travel of the vehicle body and that, when performing the autonomous travel, stops travel of the vehicle body based on detection information about an obstacle detected by the obstacle detector; and
a mode switcher (40b) that switches the autonomous travel controller between an effective mode in which the autonomous travel controller when performing the autonomous travel is allowed to stop travel of the vehicle body based on the detection information and an ineffective mode in which the autonomous travel controller when performing the autonomous travel is not allowed to stop travel of the vehicle body based on the detection information.