JP3044160B2 - Light receiving device and traveling control device for beam light guided work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention receives a guiding light beam to detect a deviation in a vehicle width direction from a guiding light beam projected by a light beam projecting means provided on the ground side. The present invention relates to a light receiving device for a beam light guiding type working vehicle provided with a steering control optical sensor in a work vehicle, and a traveling control device for a beam light guiding type working vehicle provided with the light receiving device.

[0002]

2. Description of the Related Art In the above-mentioned beam light guiding type working vehicle,
Conventionally, as shown in FIG. 20A, for example, in the case of a work vehicle V for rice planting as a beam light guiding work vehicle, the work vehicle V is one side M of a work place K which is a rectangular field.
2 is received by the steering control sensor S1 on the left side of the vehicle body and is guided along the longitudinal direction of the vehicle body 2 to automatically travel along the guiding beam light A1.
After entering the work place K from the entrance Mi provided at one end of the head 1, it turns at each of the headland portions K1 and K2 at both ends in the longitudinal direction of one side M2 while traveling back and forth along the longitudinal direction. The planting work is performed on the work target portion Ks on the center side. Thereafter, 90 from the end (the lower right position in the figure) of the final traveling stroke of the work target portion Ks to the beginning of the first traveling stroke of the second headland portion K2 adjacent to the side M4 facing the side M1. In this state, the steering control sensor S1 on the left side of the vehicle body receives the guiding light beam A1 projected along the longitudinal direction of the side M2 from the steering control sensor S1 on the left side of the vehicle body. At S1, the state is switched to a state of receiving the guiding light beam A2 projected along the longitudinal direction of the side M1. After that, the second light is applied along the guiding light beam A2.
After reciprocating the two traveling steps of the headland portion K2, the work target portion Ks is moved from the end of the stroke of the second headland portion K2.
To the starting end of the traveling stroke portion K3 adjacent to the lower side M3 of the figure left by the operation for the vehicle, turning right by 90 degrees (in this case, the guiding beam received by the steering control sensor S1 on the right side of the vehicle body). The light travels along the traveling stroke portion K3 (switching the light from A2 to A1), and then turns right at the end of the traveling stroke portion K3 (in this case, the guidance control sensor S1 on the right side of the vehicle body receives the light). (Switch the light beam from A1 to A2)
After traveling in a non-working state on the outer side of the first headland portion K1 adjacent to the side M1 and reciprocating two strokes, finally, the stroke end portion of the first headland portion K1 (upper end in the figure) From 9
The vehicle turns left by 0 degrees and leaves the work site K from the entrance Mi.

[0003]

In the above prior art, the work vehicle V is moved 90 degrees from the end of the final travel of the work portion Ks to the beginning of the first travel of the second headland portion K2. When the vehicle is turned left (the lower right position in FIG. 20A), the steering control sensor S1 to be used is switched from the steering control sensor S1 on the left side of the vehicle to the steering control sensor S1 on the right side of the vehicle. Steering control sensor S1 on the right side of the vehicle
Receives the guiding light beam A2 in the first traveling process of the second headland portion K2, and along the first traveling process of the second headland portion K2 based on the light receiving information of the guiding beam light A2. It will be driven automatically. However, FIG.
As shown in the figure, during the turn, the steering control sensor S1 on the right side of the vehicle body receives the guiding light beam A1 of the previous stroke, or the steering control sensor S1 generates the guiding light beams A1 and A2. When located at the intersection, the guiding light beam A1 of the previous step and the guiding light beam A2 of the next step
May be received at the same time. In the former case,
The received guiding light beam A1 is erroneously regarded as the guiding light beam A2 of the next process, and in the latter case, the guiding light beam A1 of the previous process is distinguished from the guiding light beam A2 of the next process. In any case, there is a disadvantage that the vehicle cannot automatically travel properly along the next travel (the first travel travel of the second headland portion K2).

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to solve the above-mentioned drawbacks of the prior art, in which a steering control sensor automatically guides a travel path to be traveled. Light-receiving device for a light-guided work vehicle that can reliably receive light, and a light-guided work that enables a work vehicle equipped with such a light-receiving device to properly and automatically travel along the next travel path It is to obtain a traveling control device for a vehicle.

[0005]

According to the present invention, there is provided a light receiving device for a light beam guiding type working vehicle according to the present invention, which is displaced in a lateral direction of a vehicle body from a guiding light beam projected by a light beam projecting means provided on the ground side. A steering control optical sensor for receiving the guiding beam light is a light receiving device for a beam light guiding type working vehicle provided in a working vehicle, the first characteristic configuration of which is A light source for receiving the guidance light, which is incident on the front side of the light receiving unit of the steering control optical sensor at a predetermined angle or more in the vehicle width direction with respect to the vehicle longitudinal direction as a reference, so as not to be incident on the light receiving unit. (1) The point that the incident light limiting means is provided.

A second characteristic configuration is that the light incident on the front side of the light receiving section of the steering control optical sensor is inclined at a predetermined angle or more in the vertical direction of the vehicle with respect to the longitudinal direction of the vehicle. A second incident light restricting means for restricting the light from entering the portion.

A third characteristic configuration is that two guiding light beams from the light beam projecting means are projected in a state of being orthogonal to each other, and the first incident light restricting means is arranged so that the first incident light restricting means refers to the vehicle longitudinal direction as a reference. The present invention is characterized in that the guiding light beam incident in a state of being inclined at least 45 degrees in the lateral width direction is not incident on the light receiving unit.

A fourth characteristic configuration is that the first incident light restricting means comprises a plurality of vertical wall-shaped first light shields juxtaposed at predetermined intervals in the width direction of the vehicle body along a vertical plane. The second incident light restricting means is constituted by a large number of side wall-shaped second light shields juxtaposed at predetermined intervals in the vehicle body vertical direction along a horizontal plane.

A fifth characteristic configuration is that the first or the second
The incident light limiting means is formed in a film-like body that embeds and holds the first light shield or the second light shield in a light transmitting member.

The feature configuration of the traveling control device for a beam-guided work vehicle according to the present invention is provided in a state where the work vehicles provided with the light receiving devices having the above-described first to fifth feature configurations intersect. The light beam projecting means is provided so as to project the guiding light beam along the longitudinal direction of each of the two traveling steps so as to automatically travel along each of the two traveling steps. Steering means for controlling the steering of the work vehicle, and the steering means so that the work vehicle automatically travels along each of the two travel paths based on light reception information of the steering control optical sensor. And the work vehicle is controlled by the work vehicle at the intersection of the two traveling steps.
After turning along a set turning pattern from a state along one traveling stroke of the two traveling strokes, after the steering control optical sensor stops receiving the guiding beam light in the one traveling stroke, the guiding beam is then turned on. As the light is received, the operation of the steering means is controlled so that the work vehicle automatically travels along the other one of the two traveling steps based on the received information of the received guiding beam light. And control means for performing the control.

[0011]

According to the first characteristic configuration of the light receiving device for a light beam guided work vehicle according to the present invention, the guiding light beam from the light beam projecting means on the ground side is transmitted in the vehicle width direction with respect to the vehicle longitudinal direction. When the light beam is incident on the light source at a predetermined angle or more, the guiding light beam is restricted by the first incident light restricting means provided in front of the light receiving portion of the steering control optical sensor and cannot enter the light receiving portion. . On the other hand, when the guiding light beam is incident on the vehicle body at a smaller angle than the predetermined angle in the vehicle width direction with respect to the longitudinal direction of the vehicle, the guiding light beam is not restricted by the first incident light restricting means. Then, based on the received light information, a shift of the work vehicle in the body width direction of the work vehicle with respect to the guide light beam is detected.

Further, according to the second characteristic configuration, sunlight or the like incident on the vehicle body at a predetermined angle or more in the vehicle vertical direction with respect to the vehicle front-rear direction is located on the front side of the light receiving section of the steering control optical sensor. And cannot be incident on the light receiving section because of the second incident light limiting means provided in the above. On the other hand, the guiding beam light is incident on the vehicle body in the state of being inclined at an angle smaller than a predetermined angle in the vehicle vertical direction with respect to the vehicle longitudinal direction, and is incident on the light receiving unit without being restricted by the second incident light restricting means. Light reception information is obtained, and based on the light reception information, a deviation of the work vehicle in the vehicle body width direction with respect to the guiding light beam is detected.

According to the third characteristic configuration, one of the two guiding light beams projected orthogonally to each other is:
When the light beam enters the vehicle in a state where it is inclined at an angle of 45 degrees or more in the vehicle body width direction with respect to the vehicle body front-rear direction, the guiding light beam is restricted by the first incident light restricting means and cannot enter the light receiving portion, while the other The light beam enters the vehicle at an angle of less than 45 degrees in the vehicle width direction with respect to the vehicle front-rear direction, enters the light receiving unit without being restricted by the first incident light restricting means, and is received. Based on the information, the shift of the work vehicle in the vehicle width direction with respect to the guide light beam is detected.

According to the fourth characteristic configuration, for example, FIG.
As illustrated in FIG. 9, the wall length a along the vertical plane of the vertical wall-shaped first light-shielding members 20a arranged in parallel with a predetermined interval in the vehicle body width direction along the vertical plane along the vertical plane and the vehicle body An inclination angle θ equal to or greater than a predetermined angle determined by the width b in the width direction.
1. The guiding light beams A1 and A2 incident in a state of being inclined in the vehicle body width direction with respect to the vehicle body front-rear direction J are shielded by the first wall-shaped first light shield 20a, and are received by the light receiving section S1a (S
1b) cannot be incident. Also, it is determined by the wall length a 'along the horizontal plane of the horizontal wall-shaped second light-shielding bodies 21a which are juxtaposed at predetermined intervals in the vehicle body vertical direction along the horizontal plane and the distance b' in the vehicle vertical direction. The light incident in a state of being inclined in the vertical direction of the vehicle body with respect to the vehicle body front-rear direction J with a tilt angle θ2 equal to or larger than a predetermined angle is reflected by the second light-shielding body 21 a having
And cannot enter the light receiving section S1a (S1b).

According to the fifth characteristic configuration, for example, FIG.
As illustrated in FIG. 9, a large number of vertical wall-shaped first light-shielding members 20 a are embedded and held in the light-transmitting member 22, and are inclined at a predetermined angle or more in the vehicle width direction with respect to the vehicle front-rear direction. Guiding light beam A1, incident at an angle θ1
A2 passes through the light transmissive member 22, but is blocked by the first light shield 20a having a vertical wall shape, cannot enter the light receiving portion S1a (S1b), and has a large number of second light shield members 21a having a horizontal wall shape. The light that is embedded in and held in the light transmissive member 22 and that is incident on the vehicle body up-down direction at an inclination angle θ2 equal to or greater than the predetermined angle with respect to the vehicle body front-rear direction passes through the light transmissive member 22 but has 2 The light receiving unit S1a is shielded from light by the light shield 21a.
(S1b) cannot be incident.

Further, according to the characteristic configuration of the traveling control device for a light beam guided work vehicle according to the present invention, the work vehicle is detected from information received by the steering control light sensor for the guided light beam. The steering device is operated based on the deviation in the lateral width of the vehicle body to automatically travel along one of the two traveling processes provided in an intersecting state, and the steering device is operated at the intersection of the two traveling processes. The directional means is operated to make a turning movement in a set turning pattern from a state along the one traveling stroke. At this time, as shown in FIG. 18, for example, after the right steering control optical sensor S1 does not receive the guiding light beam A1 in the one traveling stroke, the used sensor is changed to the left steering control light. While switching to sensor S1,
When the guiding light beam received by the steering control optical sensor S1 on the left side is examined next, at the position (b) in the drawing in the middle of turning, the light before entering the steering control optical sensor S1 on the left side is shown. Since the guiding light beam A1 in the process has an inclination angle θ1 equal to or larger than the predetermined angle in the vehicle width direction with respect to the vehicle front-rear direction J, the light beam cannot be incident on the light receiving unit and light receiving information cannot be obtained. On the other hand, at the position (c) in the figure where the turning operation is almost completed, the guiding light beam A2 of the stroke after being incident on the steering control optical sensor S1 on the left side thereof is the vehicle width in the vehicle longitudinal direction J as a reference. Since the inclination angle in the direction is smaller than the predetermined angle, the light is incident on the light receiving section and light receiving information is obtained. Therefore, the steering device is operated based on the deviation in the vehicle width direction detected from the received light information of the received guiding light beam A2, and the vehicle automatically travels along the other traveling path. As shown by the two-dot chain line in (b) of FIG.
Even when the light beams A1 and A2 are received simultaneously, as described above, only the light beam A2 in the subsequent process is incident and light reception information is obtained.

[0017]

According to the first aspect of the light receiving device for a light beam guided work vehicle according to the present invention, the light receiving device is tilted at an angle smaller than a predetermined angle in the vehicle width direction with respect to the vehicle front-rear direction. Since only the incident guiding light beam enters the light receiving portion of the steering control optical sensor and is received, the guiding light beam that is normally projected within a predetermined angle on both sides in the longitudinal direction of the vehicle body of the work vehicle is received. On the other hand, the guiding beam light greatly inclined in the vehicle width direction from the vehicle front-rear direction of the working vehicle is not erroneously received, and the steering control sensor can reliably receive the appropriate guiding beam light, So,
A light receiving device for a light guide type work vehicle, which can appropriately detect a deviation of the work vehicle in the lateral width direction of the work vehicle with respect to the guide light beam based on the received light information.

According to the second characteristic configuration, the guiding light beam is made incident on the light receiving portion of the steering control optical sensor,
Since disturbance light such as sunlight other than the guiding beam light is not made incident on the light receiving portion of the steering control optical sensor, only the guiding beam light can be reliably received, and the effect of the first characteristic configuration can be obtained. Suitable means for realization are obtained.

According to the third feature configuration, for example, in the case where the light beam guided work vehicle is automatically driven in a state parallel to each of two adjacent sides of a rectangular work place, the first feature is provided. Suitable means for realizing the effect of the configuration can be obtained.

Further, according to the fourth characteristic configuration, the first or second incident light restricting means can be formed as a simple member such as a black metal plate or a resin plate as a constituent element.
Suitable means for realizing the effect of the second characteristic configuration can be obtained.

According to the fifth characteristic configuration, the first or second incident light limiting means is a film in which, for example, a black metal plate or a resin plate is embedded and held in a light-transmitting member such as a transparent resin. A simple structure such as forming the film-like body and attaching the film-like body to the front surface of the light receiving portion of the steering control optical sensor can be realized, thereby obtaining more preferable means in the fourth characteristic configuration. Can be

Further, according to the characteristic configuration of the traveling control device for a beam-guided work vehicle according to the present invention, the work vehicle moves from the state along one traveling stroke at the intersection of the two traveling strokes to the next traveling vehicle. In the case of a turning movement between adjacent traveling steps in a state along the traveling step, the steering control sensor surely receives the guiding light beam of the next traveling step after the turning, and based on the received light information, the next A travel control device for a beam-guided work vehicle that can appropriately and automatically travel along the travel path is obtained.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a rice planting work vehicle as a light beam guided work vehicle will be described below with reference to the drawings.

As shown in FIG. 1, one end (upper end in the figure) of one reference side M1 of a plurality of sides surrounding a rectangular work field (field) K, an adjacent side adjacent to the reference side M1 M
2, an entrance Mi through which the work vehicle V enters and exits while traveling along the longitudinal direction of M3, and the adjacent side M
In the longitudinal direction of M2 and M3, work is performed along the longitudinal direction of the adjacent sides M2 and M3, with both end sides of the work site K being headland portions K1 and K2 and the center portion being a work target portion Ks. A reciprocating operation for working on the work target portion Ks is performed while the vehicle V reciprocates, and then the work vehicle V is reciprocated along the longitudinal direction of the reference side M1 in both headland portions K1 and K2. Headland work is performed on the headland portions K1 and K2. The work target portion Ks and the headland portions K1 and K2 are two right and left sides provided along the reference side M1 at both end positions of the work target portion Ks in the longitudinal direction of the adjacent sides M2 and M3. Are separated by boundary lines Y, Y.

The reference side M1 in the work target portion Ks
Work process R1 as a plurality of traveling processes arranged in the longitudinal direction of the vehicle
And a first light beam projection device B1 for projecting the light beam A1 for guiding along the longitudinal direction of the work process R1 in order to guide the work vehicle V along each of the pair of headland portions K
First headland portion K adjacent to reference side M1 of K1 and K2
In each of the second headland portions K2 adjacent to the opposing side M4 opposing the reference side M1 and the reference side M1, the work vehicle moves along each of a plurality of operation steps R2 as a plurality of traveling steps arranged in the longitudinal direction of the adjacent sides M2 and M3. In order to guide V, a second light beam projection device B2 that projects the guiding light beam A2 along the longitudinal direction of the work process R2 is provided. That is, two traveling steps R1 and R provided in a state where the work vehicle V intersects (orthogonally).
2 along the longitudinal directions of the two traveling steps R1 and R2, that is, along the longitudinal directions of the reference side M1 and the adjacent side M2, respectively. Two light beam projection devices B as light beam projection means for projecting the two guiding light beams A1 and A2
1, B2 are provided on the ground side.

The first light beam projection device B1 is basically installed at a boundary position between two adjacent work steps of the plurality of work steps R1 at a ratio of one to the two work steps. However, the figure shows a case where the number of work steps R1 is an odd number, and one first light beam projection device B1 is arranged only for the uppermost work step R1. Further, the second light beam projection device B2 is installed at the boundary position of the work process because the plurality of work processes R2 are two. or,
In the figure, the light beam A3 is projected inside the projection position of the light beam A2 for guidance from the second light beam projection device B2 in the longitudinal direction of the adjacent sides M2 and M3 in parallel with the light beam A2 for guidance. A third light beam projection device B3 is provided. Although not described in detail, each beam light projection device B
Reference numerals 1, B2, and B3 are configured by a laser device or the like, and the light beams A1, A2, and A3 are scanned in a predetermined angle range in the vertical direction (see FIG. 2).

Next, the traveling route of the work vehicle V will be described with reference to FIG. First, a final work area portion R1a connected to the entrance Mi along the longitudinal direction of the adjacent sides M2 and M3,
In addition, the reciprocating operation is performed while leaving the relay work site portion R1b adjacent to the adjacent side M3 that is located away from the entrance Mi. Here, the final work place portion R1a is the reference side M1
Of the plurality of work steps R1 arranged in the longitudinal direction of the work area, the work place part corresponding to the uppermost work step, and the relay work place part R1b is the lower work side of the plurality of work steps R1. This is the work area corresponding to the process.

In the reciprocating operation, specifically, the work route R1 farthest from the entrance Mi except for the relay work site portion R1b is defined by the right boundary line Y indicating the work start position at the start end thereof. It starts from the upper Pst point toward the left in the figure. Therefore, along the route shown in FIG.
While the vehicle is stopped at the point h and the first seedling replenishment is performed, the vehicle travels forward to the Pst point in a non-working state. After this, the work vehicle V
Is stopped at the start end of each of the work steps R1 and R2 on the reference side M1 side, seedling replenishment is appropriately performed according to the consumption state of the seedlings. Upon reaching the Pst point, the planting device 6 is driven to start planting work, and thereafter, the left and right headland portions K1, K2
Reciprocating in each work process R1 while turning 180 degrees,
In the final work process R1 (the second process from the top in the drawing) of the work target portion Ks, the right boundary line Y is guided by the guide light beam A1 based on the detection information of the right steering control optical sensor S1. The vehicle travels to the upper end position Pen.

Thereafter, a first headland portion K1 adjacent to the reference side M1 of the pair of headland portions K1 and K2, and
The headland work of working the second headland portion K2 adjacent to the opposite side M4 facing the reference side M1 is performed, and in the headland work, the headland work is performed between the first headland portion K1 and the second headland portion K2. In the case of the transition, the work area R1b for relay is operated while traveling the work area R1b for relay, and finally, the final work area R1a is run from the second headland portion K2 toward the entrance Mi. It is set so as to work on the final work place portion R1a.

Specifically, first, the right steering control light is moved from the end position Pen to the start end of the inner work process R2 of the two work processes R2 of the second headland portion K2. Guiding light beam A based on the detection information of sensor S1
1, while traveling backward from the end position Pen to the position where the rightmost guiding light beam A2 in the figure is received by the front-side sensor S2a, switching to the forward state, turning right by 90 degrees, and further receiving light. Is switched to the left-side steering control optical sensor S1, and is guided from the side while being guided by the guiding beam light A2 based on the light reception information of the left-side steering control optical sensor S1. The vehicle travels in a reverse state from the position where the projected guiding light beam A1 is received by the trigger rear sensor S2b to a position at a predetermined distance to reach the planting start position. Then, the vehicle automatically travels in the work process R2 while being guided by the guiding light beam A2 based on the detection information of the left steering control optical sensor S1 in the forward state.

Thereafter, the work stroke R2 inside the second headland part K2, the work R1b inside the relay work land part R1b, the work stroke R2 inside the first headland part K1, and the first headland part K
1, the outer process R2, the outer process R1b outside the relay work site portion R1b, and the outer process R2 outside the second headland portion K2, in that order, at the end of each process at the beginning of the next process. The vehicle automatically travels while turning and moving to the section. Finally, the vehicle travels straight ahead in the final work place portion R1a in the forward state and exits the work place from the entrance Mi.

In order to carry out each of the work steps in the reciprocating work and the headland work in the forward state, the work vehicle V is moved forward by one stroke and then moved 180 degrees or 90 degrees.
A turn is made to move to an adjacent stroke while changing the direction. That is, in the turning for movement between the respective work processes R1 in the reciprocating work and between the respective work processes R2 in the headland work, the direction is changed by 180 degrees, and the work of the headland work is performed from the work process R1 of the reciprocating work. In the turning for the movement to the process R2, the work process R2 of the headland work and the relay work site portion R1b, and the turning for moving from the work process R2 of the headland work to the final work site portion R1a, 90
The direction is changed.

The construction of the working vehicle V will be described.
As shown in FIGS. 2 and 3, a seedling planting device 6 that can be switched between a ground working state and a non-working state is provided at a rear portion of a vehicle body 5 having a pair of left and right front wheels 3 and a rear wheel 4 so as to be able to move up and down and The drive is provided so as to be freely stopped. That is, when the vehicle is driven in the lowered state, it is the ground work state, and other states are the non-work state. As shown in FIG. 4, the front and rear wheels 3, 4 are configured so that the left and right wheels can be individually steered, and the steering hydraulic cylinders 7, 8 and the electromagnetically operated control valves 9 for them are controlled. , 10 are provided. That is, a two-wheel steering system in which only one of the front wheel 3 or the rear wheel 4 is steered, a four-wheel steering system in which the front and rear wheels 3, 4 are steered in the opposite phase and at the same angle, and the front and rear wheels 3, 4 in the same phase In addition, three types of steering systems, that is, a parallel steering system that is steered at the same angle, can be selectively used. As described above, the two hydraulic cylinders 7 and 8 and the two control valves 9 and 10 constitute steering means 7 to 10 for steering the work vehicle V.

In FIG. 4, reference numeral 11 denotes a hydraulic stepless transmission for shifting the output from the engine E to simultaneously drive each of the front and rear wheels 3, 4; 12, an electric motor for the shift operation; and 13, a planting device. 6, a hydraulic cylinder for raising and lowering, 14 a control valve thereof, 15 an electromagnetically operated planting clutch for intermittently driving the planting device 6 by the engine E, and 16 a work vehicle V
A control device using a microcomputer for controlling the running of the plant and the operation of the planting device 6, based on information detected by various sensors described later and work data stored in advance, the shift motor 12, the control valves 9 , 10,1
4, and each of the planting clutches 15 is configured to be controlled.

The sensors mounted on the work vehicle V will be described. As shown in FIG. 4, steering angle detection sensors R1 and R2 using potentiometers for detecting the steering angles of the front and rear wheels 3 and 4 respectively. A vehicle speed sensor R3 using a potentiometer for indirectly detecting the forward / backward traveling state and the vehicle speed based on the shift state of the transmission 11, and an encoder S3 for counting the number of revolutions of the output shaft of the transmission 11 and detecting the traveling distance.
An orientation sensor S4 for detecting the body direction of the work vehicle V, a tilt sensor S6 installed on the planting device 6 to detect a tilt angle in the lateral direction of the vehicle body, A potentiometer S5 to be described later, which is installed at the connection point, is provided.

As shown in FIGS. 2 and 3, the work vehicle V is provided with guiding light beams A1 and A2 projected by the first beam light projecting device B1 and the second beam light projecting device B2, respectively. In order to detect a shift in the lateral direction of the vehicle body with respect to the vehicle, the steering control optical sensor S1 that receives the guiding light beams A1 and A2, and the work vehicle V includes the first beam light projecting device B1 or the second
Guiding light beams A1, A2 from the light beam projecting device B2
When the vehicle is automatically traveling along, the guiding light beams A2, A from the second light beam projecting device B2 or the first light beam projecting device B1 intersecting the guiding light beams A1, A2.
1 and the light beam A3 from the third light beam projection device B3
And a trigger optical sensor S2 for receiving light. Note that the steering control optical sensor S1 can receive the guiding light beams A1 and A2 on either side of the vehicle body.
A pair of left and right optical sensors for trigger S2 are provided on both left and right sides of the front part of the vehicle body on a line connecting both axes of the front wheel 3 in plan view. Sensors S2a and S2b,
The front sensor S2a is located a predetermined distance ahead of a line connecting both axes of the front wheel 3, and the rear sensor S2b is located on a line connecting both axes of the rear wheel 4. Incidentally, the trigger optical sensor S2 is provided with light beams A1, A
Only the presence or absence of light reception for A2 and A3 is detected, and the light reception position cannot be detected.

The steering control optical sensor S1 will be further described with reference to FIG. 5. As shown in FIG. 5, a pair of front and rear optical sensors S1 are arranged side by side at an interval d in the vehicle longitudinal direction and at intervals in the vertical direction. Optical sensors S1a and S1b as light receiving units
Each of the pair of front and rear optical sensors S1a and S1b has a plurality of light receiving elements D arranged side by side in the vehicle width direction, and determines the position of the light receiving element D0 located at the sensor center in the width direction. As a reference, the guiding light beams A1, A2
Light receiving position in the vehicle body width direction, that is, the position X of the light receiving element D
1 and X2 can be detected. or,
In order to be able to receive the light beams A1 and A2 for guiding without any difference even when the light beams A1 and A2 are incident from any direction of the front and rear of the vehicle body, the light sensors S1a and S1b respectively receive the incident light from each of the front and rear directions of the vehicle body. Mirror 1 that reflects toward the light receiving surface
8 is provided.

As shown in FIG. 7 to FIG. 9, a state in which the optical sensors S1a and S1b are inclined at a predetermined angle (specifically, 45 degrees) in the vehicle width direction with respect to the vehicle front-back direction J as a reference. A first incident light restricting means 20 for restricting the guiding light beams A1 and A2 incident on the optical sensors S1a and S1b so as not to enter the optical sensors S1a and S1b; And second incident light restricting means 21 for restricting the light incident on the optical sensors S1a and S1b so as not to enter the optical sensors S1a and S1b. Specifically, the first incident light restricting means 20 is composed of a large number of vertical wall-shaped first light shields 20a juxtaposed at predetermined intervals in the vehicle body width direction along the vertical plane, and Second
The incident light restricting means 21 is composed of a large number of side wall-shaped second light shields 21a which are juxtaposed at predetermined intervals in the vehicle body vertical direction along the horizontal plane. The first light shield 20a is
The length a of the vehicle body front-back direction and the installation interval b in the vehicle body width direction are substantially the same, and the inclination angle θ1 of the guiding light beams A1, A2 in the vehicle body width direction with respect to the vehicle body front-back direction J is 4
When the angle is smaller than 5 degrees, the light is incident on the optical sensors S1a and S1b, but when the inclination angle θ1 is 45 degrees or more, the light is not incident on the optical sensors S1a and S1b (see FIG. 8). Further, the second light-shielding body 21a is formed such that the length a 'in the vehicle front-rear direction is longer than the installation interval b' in the vehicle vertical direction, and disturbs external light such as sunlight entering the vehicle vertical direction at an inclination angle θ2. The light is prevented from entering the optical sensors S1a and S1b as much as possible (see FIG. 9). Further, the first and second incident light limiting means 20 and 21 are provided with first and second light shields 20a and 20a.
1a is formed in a film-like body F embedded and held in a light-transmissive member 22 such as a transparent resin, and the film-like body F is attached to the front side of the optical sensors S1a and S1b (see FIG. 9). .

The control structure for detecting the displacement of the vehicle body 5 in the lateral direction of the vehicle body by the steering control optical sensor S1 will be described. A pair of optical sensors S before and after the steering control optical sensor S1 will be described.
On the basis of the positions X1 and X2 of the light receiving elements 1a and S1b and the distance d in the longitudinal direction of the vehicle body, the inclination φ of the vehicle body 5 with respect to the projection direction of the guiding light beams A1 and A2 and the lateral width direction are obtained from the following equations. And the deviation x of the position at.

[0040]

## EQU1 ## φ = tan ^-1 (| X1-X2 | / d) x = X1

However, the deviation x in the lateral width direction is a state in which the vehicle body is not tilted, and when the vehicle body is rolling and tilting, it is necessary to perform correction excluding an error due to the tilt. Hereinafter, a configuration for obtaining the correction amount will be described. As shown in FIG.
Is rotatably connected around a horizontal axis along the vehicle body front-rear direction at a connection point to the vehicle body 5, and detects a rotation angle of the planting apparatus 6 and the vehicle body 5 around the horizontal axis at the connection point. The control device 16 controls the tilt sensor S6 so that a potentiometer S5 is installed and the planting device 6 is oriented horizontally in the lateral direction of the vehicle body.
Based on the detection information, the tilting means M including a link mechanism and a driving electric motor (not shown) is operated (see FIG. 4). Therefore, the rolling angle of the vehicle body 5 is obtained by adding and subtracting both the detection angles of the potentiometer S5 and the inclination sensor S6. And FIG.
As shown in the figure, the connection point and the steering control optical sensor S1
The height difference on the vehicle body is L1, the lateral distance on the vehicle body from the connection point (the center of the vehicle body left and right) to the center of the light receiving section of the steering control optical sensor S1 is L2, and the rolling angle of the vehicle body is L2. Is set to θ, a lateral distance L3 from the connection point in the state where the vehicle body is inclined to the center of the light receiving portion of the steering control optical sensor S1 is determined, and from this L3, a lateral distance L3 when the vehicle body 5 is not inclined is determined. The amount ΔL obtained by subtracting the distance L2 is the correction amount. Accordingly, the deviation x ′ after the inclination correction is obtained as a value x ′ obtained by adding the correction amount ΔL to the deviation x. By the way,
When θ = 0, ΔL = L2−L2 = 0, and x ′ =
x.

[0042]

L3 = L1 × sin θ + L2 × cos θ ΔL = (L3−L2) x ′ = x + ΔL

In this example, the deviation x of the position in the width direction is the light receiving position of one of the pair of optical sensors S1a and S1b (S1a). In order to do so, an average value of the light receiving positions X1 and X2 of the pair of optical sensors S1a and S1b may be used. Then, the work vehicle V is subjected to steering control by setting a target steering angle such that both the inclination φ and the deviation x ′ become zero. However, in the present embodiment, during straight running in each work process, steering control is performed in a two-wheel steering mode in which only the front wheels 3 are steered.

The control unit 16 controls the steering units 7 to 10 and the planting section 6 based on the detection information of various sensors such as the steering control optical sensor S1 and the preset work schedule information. It is configured to control the operation of various devices. Then, using the control device 16,
Based on the light reception information of the steering control optical sensor S1, the work vehicle V has two work processes R1, R2
The steering means 7 to 1 so as to automatically travel along each of
0, and the two work steps R1, R
The work vehicle V has two work steps R1,
R2 is turned in a set turning pattern from a state along one of the work steps R1 and R2 of R2, and the steering control optical sensor S
1 is the guiding light beam A1, in the one traveling process.
After no longer receiving A2, the guiding light beam A1,
A2 is received, and the received guiding beam light A is received.
The control means 100 controls the operation of the steering means 7 to 10 so that the work vehicle V automatically travels along the other one of the two traveling steps based on the received light information of A1 and A2. I have.

Further, the control device 16 moves the work vehicle V forward by one stroke so that the work vehicle V performs each work process in the reciprocating work and the headland work in the forward state, and then, The work vehicle V receives the guiding light beams A1, from the first light beam projector B1 or the second light beam projector B2.
When the vehicle is automatically traveling along A2, the guiding beam light A from the second beam light projecting device B2 or the first beam light projecting device B1 crossing the guiding light beams A1 and A2.
2, the start position of the 180-degree or 90-degree turning operation from the end of each stroke to the start of the next stroke adjacent to it, based on the light-receiving information of the trigger optical sensor S2 that receives A1, It is configured to set the starting position of the turning operation from one work process R1, R2 to the other work process R1, R2 at the intersection of the two work processes R1, R2.

Next, the operation of the control unit 16 will be described with reference to the flowcharts shown in FIGS. As shown in FIG. 10, the entire processing flow includes communication units and actuators (not shown) such as RS232C (the speed change motor 12, the control valves 9, 10, and 14, and
After the initialization process for the planting clutch 15) is performed, a work plan setting process for setting a work plan is performed. Next, read the corresponding control data based on the work plan set in the work plan set process,
In addition, a vehicle control process for actually executing the vehicle control based on the control data is performed. The execution state of the work plan by the vehicle body control processing is checked by the work plan check processing, and when the end of one work plan is confirmed, necessary communication processing to the ground side or the like is performed, and then the work end instruction is issued. If there is, end processing is performed, otherwise, the flow from the work plan set processing is repeated. In order to control the progress of the flow, when a new work plan is set in the work plan set processing, a plan flag is set, and when the end of the work plan is confirmed in the work plan check processing, The plan flag is reset.

In the vehicle body control processing, as shown in FIG. 11, first, it is checked whether or not the plan flag is set. If the plan flag is reset, no processing is performed.
When the plan flag is in the set state, the control contents set in the work plan set processing are read out, and it is checked whether or not the corresponding processing actually exists. As shown in the figure, the processing corresponding to the above-mentioned control contents includes a stop processing for stopping the work vehicle V, and a straight movement for moving the work vehicle V straight forward a set distance based on the distance measurement information by the encoder S3 in the forward or backward state. Processing at the distance measurement), the trigger sensor S when the work vehicle V is moving forward or backward.
2 is a straight-ahead process (ending with light source measurement) in which the guide light beams A1 and A2 travel straight to a position where the set number of times is detected, a turning process of turning from the end of each work process R1 and R2 to the start of the next process, Trajectory convergence processing for making the steering control sensor S1 properly receive the guiding light beams A1 and A2, and seedling supply apparatus processing for instructing seedling replenishment and driving control of the planting apparatus 6. Is prepared. still,
In the turning processing and the track convergence processing, the steering of the vehicle body is controlled by four-wheel steering.

Next, the flow of the turning process will be described in detail. As shown in FIGS. 12 to 16, first, the vehicle body direction data is obtained from the direction sensor S4 (step 0). The turning angle (90
In addition, the inversion azimuth, ie, the target azimuth, is calculated by adding / subtracting the rotation angle or 180 °), and the light receiving determination region for determining the reception of the guiding light beam in the next process (the vehicle speed is reduced in this region. ) Is set within a range of a predetermined angle (45 degrees) on both sides of the target azimuth as a center, and a turnable area that allows turning beyond the target azimuth is defined as an angle obtained by adding a predetermined angle to the target azimuth. Set and set the solenoid to release the brake. Then, after resetting the distance data from the encoder S3 (step 2) and setting the steering angle for turning in the set turning pattern (step 3), the transmission 11 is set to a predetermined shift state, and the planting device 6 is set. Is raised to stop the drive (step 4), and the steering angle data is input (step 5).

In step 6, the necessity of double-speed operation is determined based on the steering angle, and if the double-speed operation is not necessary, vehicle azimuth data is obtained.
It is checked whether or not it has reached the light receiving determination area. Here, if it has reached the light receiving determination area, the transmission 11 is brought into the neutral state, abnormal termination processing is performed (step 16), and the processing is terminated. If it has not reached the light receiving determination area, the encoder S3
And if it is determined that the distance exceeds the limit distance in the turning movement based on the distance data, abnormal stop processing is performed, and then abnormal end processing is performed (step 1).
6) Finish the process, but if it is not over, repeat the flow from step 5 while raising the planting device 6 and stopping the driving. On the other hand, if you need double speed operation,
A double-speed operation device (not shown) is turned on to obtain vehicle body direction data (step 9), and then the process proceeds to step 10.

In step 10, it is determined whether or not the vehicle is in the deceleration area, that is, in the light receiving determination region, based on the body direction. If the distance is not within the deceleration area, the distance data is obtained from the encoder S3. If it is determined in step 11 that the overrun has occurred, the abnormal stop processing is performed, and then the abnormal end processing is performed. (Step 16) The process ends, but if no overrun has occurred, the flow from step 9 is repeated. On the other hand, if it is within the deceleration area,
After decelerating the vehicle speed, the received light data of the left or right steering control optical sensor S1 to be used in the next step is fetched (step 12). Check the light receiving condition of here,
If it is in the non-light-receiving state, after obtaining the vehicle orientation data,
In step 14, it is checked whether or not the vehicle is in the turnable area,
If it exceeds the turnable area, after performing an abnormal stop process, an abnormal end process is performed (step 16), and the process ends. If it does not exceed the turnable area, distance data is obtained, and at step 15, the presence or absence of overrun is checked. If overrun, abnormal stop processing is performed, and then abnormal end processing is performed. (Step 16) The process ends, but if no overrun has occurred, the flow from step 12 is repeated. On the other hand, if it is in the light receiving state, after the stop processing is performed, the stop of the vehicle body is confirmed in step 17, the light receiving data of the steering control optical sensor S 1 is fetched, and the process proceeds to step 18.

In step 18, the steering control optical sensor S
It is checked whether the light receiving position of No. 1 is the center position D0. If the light receiving position is the center position, the neutral setting of the steering (step 23), the setting of the solenoid for brake operation (step 24), and the clutch The solenoid is set for the cutting operation (step 25), and the process is terminated. On the other hand, when the light receiving position is not at the center position, it is further checked whether the light receiving position is deviated to which side.If the light receiving position is closer to the front side, that is, the stroke side before turning, the turning direction is the same, and it is not the front side. In other words, when the vehicle is approaching the stroke side after turning, the turning direction is reversed, and the turning traveling is performed at a low speed. Then, while resetting the distance data, the limit value (for example, 1 m) of the moving distance in the turning travel is set (step 19), and the light receiving data of the steering control optical sensor S1 is taken in (step 20).
In step 21, it is checked whether the light receiving position is the center position D0. Here, if the light receiving position is not the center position, after obtaining the distance data, it is checked in step 22 whether or not the overrun has exceeded the limit value of the moving distance. After the abnormal stop processing, the abnormal end processing is performed (step 16), and the processing is finished. If the overrun is not detected, the light reception data of the steering control optical sensor S1 is fetched, and the flow from step 21 is started. repeat. In step 21, if the light receiving position is the center position, a stop process is performed, and then the flow from step 23 is performed to end the process.

Next, the flow of the steering control for automatically traveling along the guiding light beams A1 and A2 in the straight traveling process and the trajectory convergence process will be described. First, as shown in FIG. Steering (4
WS) state, and in the case of four-wheel steering, the inclination φ of the vehicle body 5 and the deviation x ′ (in the width direction) detected as described above based on the light reception data of the steering control optical sensor S1. Using the detected deviation x using the deviation corrected by the inclination of the vehicle body), the steering angles of the rear wheels 4 and the front wheels 3 are calculated,
The rear wheel 4 and the front wheel 3 are set so as to have such a turning angle. In the case of non-four-wheel steering, that is, two-wheel steering, the turning angle of the front wheel 3 is calculated from the inclination φ and the deviation x in the lateral width direction. The front wheel 4 is set so as to have the steering angle, and the rear wheel 4 is set in a neutral state.

[Another Embodiment] In the above embodiment, the working vehicle V
To travel automatically in a state parallel to each of the two sides M1 and M2 adjacent to each other on the rectangular work site K, so that the two traveling paths (the two sides M1) intersect at right angles, that is, at 90 degrees to each other. , M2, at the intersection of the work steps R1, R2) parallel to each other, the vehicle is turned while changing the azimuth of the vehicle body by an angle of 90 degrees. The present invention can also be applied to a case where a vehicle is turned while changing the vehicle body azimuth at the above-mentioned predetermined angle at an intersection of two traveling steps intersecting at a predetermined angle other than the orthogonal state so that the vehicle automatically travels in a state parallel to each of the two sides. . In this case, the light beam projecting means B1, B
The two guiding light beams from No. 2 are projected along the respective longitudinal directions of the two traveling strokes at the predetermined angle.

In the above-described embodiment, the case where the work vehicle V automatically travels while performing work (planting of seedlings on a field) along the work steps R1 and R2 as a travel step has been described. As shown in the figure, a guide route for the traveling of the work vehicle is set while appropriately intersecting the plurality of guide light beams An, and the work vehicle V is guided to the guide beam light An along each traveling path Rn of the guide route. The vehicle travels automatically without performing any work in a state where
The present invention can also be applied to the case where the vehicle is turned to the next traveling stroke Rn adjacent at the intersection of n.

Further, in the above embodiment, the work vehicle V is used for each work process R as a travel process in reciprocating work, headland work and the like.
In the first and the R2, the case where the vehicle travels in the forward state while making a turning movement from the end portion of each traveling process to the start end of the adjacent traveling process has been described. However, all the traveling processes R1 and R2 travel in the forward state. It is not necessary, and for example, in the headland work, a part of the stroke may be run in reverse.

Further, in the above embodiment, each light beam projecting means B1, which projects each light beam A1, A2, A3 for guiding,
Although B2 and B3 are configured by laser light generators, beam light generators other than laser light generators may be used.

In the above embodiment, the light receiving portions of the steering control optical sensor S1 are juxtaposed at intervals in the longitudinal direction of the vehicle body to determine the light receiving positions of the guiding light beams A1 and A2 in the vehicle width direction. A pair of optical sensors S1a and S1b are used to detect the position deviation x in the vehicle width direction by the light receiving position X1 of one (S1a) of the pair of optical sensors S1a and S1b. The inclination φ of the vehicle body based on the difference between the light receiving positions X1 and X2 in the vehicle body width direction and the distance information d in the vehicle front-rear direction.
The position deviation x and the inclination φ are determined by using the guiding light beams A1 and A2.
, But the configuration of the steering control optical sensor S1 is not limited to this.
For example, the light receiving unit is constituted by one optical sensor instead of a pair of optical sensors, and the position deviation x in the vehicle width direction obtained from the light receiving position is shifted from the guiding light beams A1 and A2 in the vehicle width direction. It may be information.

Further, in the above embodiment, both the first incident light restricting means 20 and the second incident light restricting means 21 are provided. However, for example, disturbance light other than the guiding light beams A1 and A2 is used. Under conditions that do not cause a problem, only the first incident light limiting means 20 may be provided.

In the above embodiment, the first incident light restricting means 20 and the second incident light restricting means 21 are each provided with a vertical wall-shaped first light restricting means.
Although the light-shielding body 20a or the horizontal wall-shaped second light-shielding body 21a is constituted by a large number of juxtaposed members, the invention is not limited to such a wall-shaped light-shielding body.

In the above embodiment, the first incident light restricting means 20 and the second incident light restricting means 21 are each provided with a vertical wall-shaped first light restricting means.
A plurality of light shields 20a or a plurality of side wall-shaped second light shields 21a are buried and held in the light transmissive member 22 to form the film F, but it is not necessarily formed in such a film F. There is no necessity. For example, the light-shielding members 20a and 21 having rigidity so that the wall shape can be maintained by itself.
a is connected by a plate-like or linear connecting member at the predetermined interval, or the first incident light limiting means 2
For example, when both the light blocking member 20a and the second light blocking member 21 are provided, the other light blocking member 2
It is also possible to form a groove into which 0a and 21a are inserted, and to hold each other in the groove.

In the above embodiment, the steering of the work vehicle V is configured to be capable of four-wheel steering, and the steering means 7 to
10 is constituted by a hydraulic cylinder for steering the front wheel 3 and the rear wheel 4 separately and a control valve thereof.
10 to 10 are not limited to these, and various means are possible.

In the above embodiment, the present invention is applied to a rice planting work vehicle as a beam light guiding type work vehicle. However, the present invention is applied to a work vehicle for agricultural work other than for rice planting and various kinds of vehicles for non-farm work. It can be applied to work vehicles, etc.
The specific configuration of each part at that time is variously changed according to the purpose of the work vehicle, work conditions, and the like.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[0064]

[Brief description of the drawings]

FIG. 1 is a plan view showing an entire travel route and a projection position of a guiding light beam.

FIG. 2 is a schematic side view of a work vehicle and a guiding light beam projecting unit.

FIG. 3 is a schematic plan view showing a work vehicle and a beam light detection sensor for guidance.

FIG. 4 is a block diagram of a control configuration.

FIG. 5 is an explanatory diagram of a light receiving position of a steering control optical sensor.

FIG. 6 is an explanatory diagram for correcting the inclination of the deviation detected value in the lateral direction of the vehicle body.

FIG. 7 is a schematic perspective view showing first and second incident light limiting means.

FIG. 8 is a front view showing a first incident light limiting unit.

FIG. 9 is a side view showing a steering control optical sensor and a second incident light limiting unit.

FIG. 10 is a flowchart of a control operation.

FIG. 11 is a flowchart of a control operation.

FIG. 12 is a flowchart of a control operation.

FIG. 13 is a flowchart of a control operation.

FIG. 14 is a flowchart of a control operation.

FIG. 15 is a flowchart of a control operation.

FIG. 16 is a flowchart of a control operation.

FIG. 17 is a flowchart of a control operation.

FIG. 18 is a plan view illustrating the operation of the light receiving device of the present invention.

FIG. 19 is a plan view illustrating traveling control of a light beam guided work vehicle according to another embodiment.

FIG. 20 is a plan view illustrating a light receiving device of a conventional light beam guidance type working vehicle.

[Explanation of symbols]

 B1, B2 Beam light projecting means S1 Steering control light sensor V Work vehicle S1a, S1b Light receiving unit 20 First incident light restricting means 21 Second incident light restricting means 20a First light shield 21a Second light shield 22 Light transmissivity Member F Film-shaped body 7 to 10 Steering means 100 Control means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-61705 (JP, A) JP-A-58-15208 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05D 1/02 A01B 69/00 303

Claims (6)

(57) [Claims] An operation for receiving a light beam for guiding in order to detect a deviation in a lateral width direction of the light beam for guiding projected by light beam projecting means (B1, B2) provided on the ground side. A direction control optical sensor (S1) is a light receiving device for a beam light guiding type work vehicle provided in a work vehicle (V), and a light receiving unit (S1a, S1) of the steering control optical sensor (S1).
1b) a first incidence that restricts the guide light beam that is incident on the front side of 1b) in a state of being inclined at a predetermined angle or more in the vehicle width direction with respect to the vehicle longitudinal direction as a reference so as not to enter the light receiving units (S1a, S1b). A light receiving device for a light beam guided work vehicle provided with a light limiting means (20). 2. Light incident on a front side of a light receiving section (S1a, S1b) of the steering control optical sensor (S1) in a state of being inclined by a predetermined angle or more in a vehicle vertical direction with respect to a vehicle longitudinal direction as a reference. 2. A light receiving device for a light beam guided work vehicle according to claim 1, further comprising a second incident light limiting means (21) for limiting light from entering the light receiving portions (S1a, S1b). 3. The two guiding light beams from the light beam projecting means (B1, B2) are projected in a state of being orthogonal to each other, and the first incident light limiting means (20) is set based on the longitudinal direction of the vehicle body. The guiding light beam incident at an angle of 45 degrees or more in the vehicle width direction is received by the light receiving sections (S1a, S1a).
3. The light receiving device according to claim 1, wherein the light receiving device is configured not to be incident on 1b). 4. The first incident light restricting means (20) comprises a plurality of vertical wall-shaped first light shields (20a) juxtaposed at predetermined intervals in a vehicle width direction along a vertical plane. The second incident light restricting means (21) is composed of a large number of side wall-shaped second light shields (21a) juxtaposed at predetermined intervals in the vehicle body vertical direction along a horizontal plane. 4. A light receiving device for a light beam guided work vehicle according to 2 or 3. 5. The first or second incident light limiting means (2)
0, 21) is the first light shield (20a) or the second light shield (20a).
5. The light receiving device for a beam-guided work vehicle according to claim 4, wherein the light shielding body is formed in a film-like body which is embedded and held in a light transmissive member. 6. The beam light projection so that the work vehicle (V) provided with the light receiving device according to claim 1 automatically travels along each of two traveling processes provided in an intersecting state. Means (B1, B2) are provided so as to project the guiding light beam along the longitudinal direction of each of the two traveling steps, and control the work vehicle (V) to steer the work vehicle (V). The steering vehicle (7-10) and the steering vehicle based on light reception information of the steering control optical sensor (S1) so that the work vehicle (V) automatically travels along each of the two traveling processes. The operation of the steering means (7 to 10) is controlled, and at a crossing point of the two traveling steps, the work vehicle (V) is set in a set turning pattern from a state along one of the two traveling steps. After turning, the steering control optical sensor (S1) is turned to the one side. After the guide beam light is no longer received in the travel process, the work vehicle (V) is driven by the work vehicle (V) based on the received light information of the received guide beam light after the guide beam light is received next. And a control means (100) for controlling the operation of the steering means (7 to 10) so as to automatically travel along the other travel path of the vehicle.