JPH08178650A - Position detecting device for work vehicle - Google Patents

Abstract

PURPOSE: To enable the detection range of a car body position by light beam to be expanded while avoiding expensive system configuration by providing a light reflecting body on a work vehicle side and an image pickup means for picking up the body. CONSTITUTION: A first light reflecting body 1 provided at a car body of a work vehicle is a protruded sectional triangle shaped angular bar on a downward side provided with reflecting parts 1a and 1b for reflecting a guiding beam light A1 to be projected in the car body longitudinal direction. A second light reflecting body 2 is a protruded sectional triangle shaped angular bar on the downward side provided with reflecting parts 2a and 2b for reflecting a trigger light beam A2 to be projected in the car body lateral direction. A two-dimensional image sensor S (image pickup means) picks up reflecting bodies 1 and 2 from the downward side in a status in which the respective reflecting parts 1a, 1b, 2a, and 2b can be discriminated. Based on this image pickup information, reflection of the light beams A1 and A2 at the reflecting parts 1a, 1b, 2a, and 2b is confirmed, and the car body position is detected. The reflecting bodies 1 and 2 can be made of inexpensive members such as white plastic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vehicle provided with a position detecting means for detecting a vehicle body position with respect to a light beam projected by a light beam projecting means installed on the ground side. The present invention relates to a position detection device.

[0002]

2. Description of the Related Art In the position detecting device for a work vehicle described above, conventionally, for example, in order to guide the work vehicle to automatically travel along each of a plurality of work strokes, a beam of light is emitted in the longitudinal direction of the work stroke. A light receiving sensor for detecting the light receiving position in the vehicle width direction with respect to the light beam for guiding is formed by arranging light detecting elements with a predetermined resolution in the vehicle width direction, and the light receiving position of the light receiving sensor. Based on the information, it detects the position (lateral displacement, etc.) in the lateral direction of the vehicle body with respect to the guidance light beam, and also as a trigger light beam in a state where the light beam intersects the end position of the above work process in the work process direction. Light receiving sensors consisting of a single light detecting element are arranged on both left and right side surfaces of the vehicle body so as to receive the light beam for triggering, and the light receiving sensor receives the light beam for triggering. With it, it has been to detect the start or end position of the stroke (e.g., JP-A-6-149
372). By the way, based on the detection information of the vehicle body position (position in the vehicle body widthwise direction, inclination in the vehicle body front-rear direction, etc.), steering control is performed so that the work vehicle travels along each work stroke, and the trigger vehicle is used. Based on the reception of the light beam, for example, the turning movement is performed from the end of the stroke toward the start of the next stroke.

[0003]

However, in the above-mentioned prior art, for example, a light receiving sensor for receiving the guiding light beam is constructed by arranging the light detecting elements at the projection position of the guiding light beam in the lateral direction of the vehicle body. Therefore, when trying to widen the position detection range in the lateral direction of the vehicle body with respect to the guiding light beam, there is a problem that a large number of photodetection elements are required and the light receiving sensor becomes expensive.
Since the light receiving sensor that receives the trigger light beam is composed of a single light detection element with a narrow detection range, if a light reception error occurs due to disturbance etc. when the trigger light beam is projected in that detection range However, the end of the stroke was not detected, and the work vehicle could run away. In this case, it is conceivable that the light receiving sensor for the trigger light beam is arranged with a plurality of light detecting elements to widen the detection range similarly to the light receiving sensor for the guiding light beam, but the light receiving sensor is expensive. There is a problem that becomes.

The present invention has been made in view of the above circumstances, and an object thereof is to avoid an increase in the cost of a device such as a sensor for receiving a light beam in order to solve the drawbacks of the prior art. However, it is to widen the detection range of the vehicle body position with respect to the light beams such as the guide light beam and the trigger light beam.

[0005]

A first characteristic configuration of a position detecting device for a work vehicle according to the present invention is a light reflector having a reflecting portion for reflecting the light beam, and the light reflecting member for reflecting the light beam. An image pickup means for picking up an image in a state in which the parts can be discriminated is provided, and the position detection means is configured to detect the vehicle body position based on the image pickup information of the image pickup means.

A second characteristic configuration is that the light beam is
The light is projected as a guiding beam of light along the longitudinal direction of the work stroke, and the reflecting portion of the light reflector is provided along the lateral direction of the vehicle body. It is configured to detect the position in the direction.

A third characteristic configuration is that the light reflector is
A pair of them are juxtaposed in the front-rear direction of the vehicle body, and the position detecting means is configured to detect an inclination in the front-rear direction of the vehicle body with respect to the guiding light beam.

In the fourth characteristic construction, the reflecting portion of the light reflector is inclined to the front and rear sides of the vehicle body in order to reflect the guiding beam lights projected from the front and rear sides of the vehicle body, respectively. The point is that it has two inclined surfaces.

A fifth characteristic configuration is that the light beam is
It is projected as a triggering beam of light in a state of intersecting the direction of the work stroke, and the position detecting means, as the triggering beam of light is reflected by the reflecting portion of the light reflector, It is configured to detect the start or end position.

[0010]

According to the first characteristic configuration of the present invention, the beam light projected from the beam light projection means installed on the ground side is
The image is reflected by the reflection part of the light reflector provided on the side of the work vehicle, and is imaged by the imaging means in a state where the reflection part of the light reflector can be discriminated. Then, based on the image pickup information obtained by picking up the image of the light reflector, the reflection of the beam light at the reflecting portion of the light reflector is confirmed, and the vehicle body position with respect to the light beam is detected.

According to the second characteristic construction, the guiding beam light projected along the longitudinal direction of the work stroke on the ground side is provided along the vehicle body lateral width direction of the light reflector on the working vehicle side. The image is picked up by the image pickup means in a state where it is reflected by the reflecting portion and the reflecting portion of the light reflector can be discriminated. Then, based on the imaging information obtained by imaging the light reflector, the reflection position of the guiding beam light in the vehicle width direction in the reflection portion of the light reflecting member is confirmed, and in the vehicle width direction with respect to the guidance beam light. The position is detected.

According to the third characteristic construction, the guiding beam light projected along the longitudinal direction of the working stroke is a pair of lights juxtaposed at predetermined intervals in the vehicle body front-rear direction on the working vehicle side. The image is imaged by the image pickup means in a state in which each of the reflecting portions of the reflecting body provided along the lateral direction of the vehicle body is reflected, and the reflecting portions of the pair of light reflecting bodies can be discriminated from each other. Then, based on the imaged information obtained by imaging the pair of light reflectors, the reflection position in the vehicle body lateral direction in each reflection portion of the pair of light reflectors of the guidance light beam is confirmed, and the guidance light beam is reflected. The tilt in the front-back direction of the vehicle body is detected.

According to the fourth characteristic configuration, the guiding beam light projected from the front side of the vehicle body along the longitudinal direction of the working stroke is provided in the vehicle body provided in the reflecting portion of the light reflector on the working vehicle side. Reflected by the inclined surface inclined to the front side, conversely, the guiding beam light projected from the vehicle rear side is reflected by the inclined surface inclined to the vehicle rear side provided in the reflecting portion of the light reflector,
An image is picked up by the image pickup means in a state in which the reflecting portion of the light reflector, that is, both of the inclined surfaces can be distinguished. Then, based on the imaging information obtained by imaging the light reflector, the reflection position of the guiding beam light in the vehicle width direction in the reflection portion of the light reflecting member is confirmed, and in the vehicle width direction with respect to the guidance beam light. The position is detected. In this case, if a pair of light reflectors having the above-mentioned inclined surfaces are juxtaposed in the vehicle front-rear direction, the vehicle body front-rear inclination with respect to the guiding beam light can be detected.

According to the fifth characteristic configuration, the trigger beam light projected on the ground side in a state intersecting with the direction of the working stroke is reflected by the reflecting portion of the light reflector on the working vehicle side. The image is picked up by the image pickup means in a state where the reflecting portion of the light reflector can be discriminated. Then, based on the imaging information obtained by imaging the light reflector, when it is confirmed that the trigger light beam is reflected by the reflection portion of the light reflector, it is detected that the work stroke is at the start or end position. It

[0015]

According to the first characteristic configuration of the present invention, therefore, a light reflector made of an inexpensive member such as white plastic is provided at the beam light projection position, and the entire light reflector is image sensor. Since the image is picked up by such image pickup means, the apparatus does not become expensive even if the light reflector is made large in order to widen the detection range of the vehicle body position with respect to the light beam. Therefore, even when the vehicle body position is largely deviated from the light beam, it becomes possible to properly guide the work vehicle by detecting the vehicle body position with respect to the light beam, and the device cost can be kept low. As a result, a more useful position detection device for work vehicles has been obtained.

Further, according to the second characteristic configuration, in order to widen the position detection range in the lateral direction of the vehicle body with respect to the guiding light beam projected along the longitudinal direction of the work stroke, the beam light beam is different from the conventional one. Since it is only necessary to lengthen the light reflector in the lateral direction of the vehicle body rather than arranging a large number of photodetection elements at the projection position, the position detection range in the lateral direction of the vehicle body for the guidance beam light can be expanded while keeping the device cost low. Therefore, the position detecting device in the lateral direction of the vehicle body with respect to the guiding light beam projected along the longitudinal direction of the working process can be provided with suitable means for implementing the first characteristic configuration.

Further, according to the third characteristic configuration, when the inclination in the vehicle front-rear direction with respect to the guiding light beam projected along the longitudinal direction of the work stroke is large, the detection range can be increased by increasing the vehicle front-rear direction. Since it is only necessary to lengthen the pair of light reflectors juxtaposed in the same direction in the lateral direction of the vehicle body, a position detection device for a work vehicle that detects the tilt in the vehicle longitudinal direction with respect to the guiding beam light while keeping the device cost low. , Above second
Suitable means for implementing the characteristic construction of

Further, according to the fourth characteristic configuration, the apparatus cost is detected when the position in the vehicle lateral width direction or the inclination in the vehicle longitudinal direction with respect to the guiding light beams projected from both front and rear sides of the vehicle body is detected. It is possible to widen the above-mentioned detection range while keeping the value low, and thus the position detection device for a work vehicle for detecting the vehicle body position with respect to the guidance beam light projected from both the front side and the rear side of the vehicle body. Alternatively, suitable means for implementing the third characteristic configuration can be obtained.

Further, according to the fifth characteristic configuration, in order to widen the detection range for the trigger beam light and prevent the detection error from occurring, it is sufficient to increase the size of the light reflector, thereby reducing the apparatus cost. The position detecting device for a work vehicle, which detects the start end or the end position of the work stroke based on the detection of the trigger light beam projected in a state of intersecting in the direction of the work stroke while keeping it low, includes the above first and second positions. Suitable means for implementing the third or fourth characteristic configuration can be obtained.

[0020]

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

As shown in FIG. 4, in order to guide the rice-planting work vehicle V so as to automatically travel along each of the work steps in a plurality of work steps set parallel to each other set in the field. , A guiding laser light projection device B1 as a beam light projection means for projecting the guidance light beam A1 which serves as a guide for traveling along the longitudinal direction of the work stroke, and includes a pair of adjacent work strokes among the plurality of work strokes. It is installed on the ground side so as to be shared by the work steps of (1) and (2), so that the guiding beam light A1 can be projected in each of a plurality of work steps that are parallel to each other. Although not described in detail, the guiding beam light A1 is scanned within a predetermined angle range in the vertical direction (see FIG. 5).

Further, the trigger beam light A2 for indicating the start end or the end position in the longitudinal direction of the work stroke and the start position of the turning operation for the next work stroke is converted into the guide beam light A1. A laser beam projecting device for trigger B2 as a beam light projecting means for projecting in a state intersecting (orthogonal in the figure) with respect to the projecting direction is arranged in the work process juxtaposing direction corresponding to both ends in the longitudinal direction of the work process. It is installed on the ground side of the field. This allows
As the work vehicle V reaches the end portion of each work stroke, the work vehicle V is turned 180 degrees toward the start end portion of the next work stroke, and reciprocally travels in each work stroke to make a predetermined range. The planting work in the field is continuously and automatically performed.

Explaining the structure of the work vehicle V,
As shown in FIGS. 4 and 5, a seedling planting device 6 is provided at a rear portion of a vehicle body 5 including a pair of left and right front wheels 3 and rear wheels 4 so that the seedling planting device 6 can be moved up and down and can be stopped. Further, as shown in FIG. 1, the front and rear wheels 3 and 4 are composed of a pair of left and right wheels so that the front and rear wheels can be individually steered, and steering hydraulic cylinders 7 and 8 and electromagnetic operation type cylinders for them are provided. Control valve 9,
And 10 are provided. In other words, a two-wheel steering system that steers only one of the front wheels 3 or the rear wheels 4, the front and rear wheels 3,
It is now possible to select and use three types of steering types: a four-wheel steering type that steers 4 in the opposite phase and at the same angle, and a parallel steering type that steers the front and rear wheels 3, 4 in the same phase and at the same angle. There is.

In FIG. 1, reference numeral 11 is a hydraulic continuously variable transmission that shifts the output from the engine E to drive the front and rear wheels 3 and 4 at the same time, 12 is an electric motor for gear shifting operation, 1
3 is a hydraulic cylinder for raising and lowering the planting device 6, 14 is a control valve thereof, 15 is an electromagnetically-operated planting clutch for intermittently driving the planting device 6 by the engine E, 16 is traveling of the work vehicle V, and A control device using a microcomputer for controlling the operation of the planting device 6, wherein the shifting motor 12 and the control valves 9, 1 are based on detection information from various sensors described later.
0, 14 and the planting clutch 15 are each activated.

The sensors mounted on the work vehicle V will be described. As shown in FIG. 1, steering angle detection sensors R1 and R2 using potentiometers for detecting the steering angles of the front and rear wheels 3 and 4, respectively. And a vehicle speed sensor R3 using a potentiometer that indirectly detects the forward / backward traveling state and the vehicle speed based on the speed change state of the speed change device 11, and the speed change device 11
An encoder S4 for counting the number of rotations of the output shaft and detecting the traveling distance is provided.

Further, as shown in FIGS. 4 and 5, in the plan view, the guiding beam light A1 is received in order to detect the position in the vehicle lateral direction with respect to the guiding beam light A1, and at the same time, A light-receiving sensor 17 for receiving the trigger light beam A2 for detecting the start end or end position of the work stroke is provided on the front side of the vehicle on the right side in the lateral width direction of the work vehicle V.

The structure of the light-receiving sensor 17 will be described. As shown in FIGS. 6 to 8, a reflecting portion 1a for reflecting the guiding light beam A1 projected in the longitudinal direction of the vehicle body,
1b, a first light reflector 1 formed of a rectangular bar having a convex triangular cross-section and a reflecting portion 2a, 2b for reflecting the trigger beam light A2 projected in the lateral direction of the vehicle body. A second light reflector 2 formed of a square bar having a convex triangular cross-section is provided on the side, and the first and second light reflectors 1 and 2 serving as light reflectors are respectively provided with reflecting portions 1a and 1b. And 2
A two-dimensional image sensor S is provided as an image capturing unit that captures an image from the lower side in a state where a and 2b can be discriminated.
In addition, a light-reflecting white plastic material or the like is used for the square rods forming the first and second reflectors 1 and 2.

The first light reflectors 1 are arranged side by side in the vehicle body front-rear direction at a distance d in the vertical direction with a space therebetween, and the reflection portions 1a and 1b are in a state of being along the vehicle body lateral direction. In order to reflect the guiding beam light A1 projected from the front side and the rear side of the vehicle body, two inclined surfaces 1a and 1b are respectively inclined to the front side and the rear side of the vehicle body. That is, the guiding beam light A1 from the front side of the vehicle body is reflected by the inclined surface 1a inclined to the front side of the vehicle body, and the guiding beam light A1 from the rear side of the vehicle body is reflected to the inclined surface 1b inclined to the rear side of the vehicle body. Is reflected. The reflecting portions 2a and 2b of the second light reflector 2 are provided along the vehicle front-rear direction, and are provided on the left side of the vehicle body to reflect the trigger beam light A2 projected from the left and right sides of the vehicle body. And two inclined surfaces 2a inclined to the right side, respectively
And 2b. That is, the trigger beam light A2 from the left side of the vehicle body is reflected by the inclined surface 2a inclined to the left side of the vehicle body, and the trigger beam light A2 from the right side of the vehicle body.
Is reflected by the inclined surface 2b inclined to the right side of the vehicle body.

Using the control device 16, the position detecting means 100 for detecting the vehicle body position with respect to the guiding light beam A1 and the triggering light beam 2 is constructed based on the imaging information of the image sensor S. . First, the position detecting operation for the guiding light beam A1 by the position detecting means 100 will be described. As an example of the case where the guiding beam light A1 is projected from the rear side of the vehicle body, FIG.
As shown in, the image pickup screen SG of the image sensor S includes
A pair of guiding beam light A1 reflected (left and right on the screen)
The position of each reflection portion 1b of the first light reflector 1 appears as a bright line state brighter than other positions. Therefore, with the horizontal line HL at the upper and lower center position of the screen as the origin, the ordinate X1 of the bright line at the reflecting portion 1b on the front side of the vehicle body and the ordinate X2 of the bright line at the reflecting portion 1b on the rear side of the vehicle body are set. Then, the position in the lateral direction of the vehicle body with respect to the guiding light beam A1, that is, the lateral deviation x and the inclination φ in the longitudinal direction of the vehicle body are obtained from the following equation (1). In the formula, d ′ is the length within the screen SG of the installation interval d of the pair of first light reflectors 1 in the vehicle body front-rear direction.

[0030]

(1) φ = tan ⁻¹ (| X1−X2 | / d ′) x = (X1 + X2) / 2) (1)

Next, the position detecting operation for the trigger light beam A2 by the position detecting means 100 will be described. Taking the case where the trigger light beam A2 is projected from the right side of the vehicle body as an example, as shown in FIG. 9, the second light reflector 2 on which the trigger light beam A2 is reflected is displayed on the imaging screen of the image sensor S. The position of the reflection part 2b on the right side of is visible as a brighter line state than the other parts. Therefore, when the bright line is located in the detection area Tp of a predetermined size set at the left and right center position of the screen on the reflection part 2b, the trigger beam light A2 is reflected by the reflection part 2b of the second light reflector 2. As the reflection is determined,
It is configured to detect the start or end position of the work stroke.

Then, the control device 16 is constructed so as to travel along each of the plurality of work strokes while controlling the steering of the work vehicle V based on the detection information of the lateral deviation x and the inclination φ. ing. That is, when the vehicle travels straight along each work stroke, the target steering angle is set so that the lateral deviation x and the inclination φ are both zero, and the steering control is performed in a two-wheel steering manner. When the vehicle travels from one part to the beginning of the next work stroke, the work vehicle V is turned in a set turning pattern. Specifically, as shown in FIGS. 10 and 11, the point at which the trigger beam light A2 is detected is set to e, and the encoder S4 is started from this point e.
Based on the detection information of 1, the turning operation of 180 degrees is started from the point f which has traveled the distance a, and the routes e to h which reach the end point h of the turning operation through the predetermined turning section g are set as desired turning trajectories. Thus, the set turning pattern is set.

Next, the operation of the control device 16 will be described with reference to the flow charts shown in FIGS. 2 and 3. In the work vehicle V, the guiding laser beam projection device B1 is used.
In the state where the guiding beam light A1 projected from the vehicle is received from the rear side of the vehicle body, the first work stroke set on one end side of the field starts traveling from one end side to the other end side along the longitudinal direction thereof. (See FIG. 4).

After the start of running, the steering control of the front wheels 3 is carried out in the two-wheel steering system as described above so that both the inclination φ of the vehicle body 5 and the lateral deviation x become zero. Then, as it travels a set distance from the time of receiving the triggering beam light A2 projected on one end side of the work stroke and reaches the planting start position, the planting device 6 is lowered and driving is started, Planting work will start.

When the work vehicle V reaches the end of the work stroke and receives the triggering beam light A2 (point e), the driving of the planting device 6 is stopped and the planting work is stopped. Although not described in detail, when it is determined that the work is completed based on the number of times of turning, the next turning operation is not performed, the traveling is stopped, and the entire process is ended. Then, the vehicle travels toward the point f, which is a distance a away from the point e. When the vehicle arrives at point f, it switches from the two-wheel steering type to the four-wheel steering type, and along the turning section g in order to turn the work vehicle V by 180 degrees toward the start end of the next work stroke. Rotate.

Then, the turning operation is continued until it passes the intermediate point of the turning section g, and in the latter half of the turning section g after passing the intermediate point, while checking whether or not to receive the guiding beam light A1. The turning operation is continued until the turning end point (point h). When the guiding beam light A1 is received before reaching the turning end point (point h), the steering control along the next work stroke is started by switching from the four-wheel steering type to the two-wheel steering type. .

On the other hand, if the guidance beam light A1 is not received before the turning end point (point h) is reached, the guidance beam light A1 is received by switching from the four-wheel steering system to the parallel steering system. Move the car body laterally. The direction in which the vehicle body is laterally moved when the guide light beam A1 is not received is the right side of the vehicle body traveling direction. Then, when the guiding beam light A1 is received, the parallel steering system is switched to the two-wheel steering system and the steering control along the next work stroke is started.

[Other Embodiment] In the above embodiment, the beam light A is
The light reflectors 1 and 2 that reflect the light A1 and A2 are configured by square bars having a triangular cross section that is convex downward, but the invention is not limited to this. For example, it may be configured as a square bar having a triangular cross-section that is convex upward, and in this case, the image pickup means S takes an image from the upper side. Further, it may be constituted by a round bar having a circular cross section, and in this case, the image pickup means S can take an image from either the lower side or the upper side.

Further, in the above embodiment, the reflecting portion of the light reflector 1 has two inclined surfaces 1a, 1 inclined toward the front and rear sides of the vehicle body.
Although b is provided so that the guiding beam light A1 projected from the front and rear sides of the vehicle body can be reflected, the present invention is not limited to this. For example, an inclined surface that reflects only the guiding beam light A1 from the front side of the vehicle body may be provided. In this case, it is necessary to reverse the projection direction of the guiding light beam A1 in the adjacent work process.

Further, in the above embodiment, a pair of light reflectors 1 having the reflecting portions 1a and 1b along the lateral direction of the vehicle body are juxtaposed in the vehicle longitudinal direction, and tilted in the vehicle longitudinal direction with respect to the guiding beam light A1. φ was also detected, but the inclination φ
It is also possible to simplify the configuration by using only one light reflector 1 so as to detect only the position (lateral displacement x) in the lateral direction of the vehicle body without detecting

In the above embodiment, the trigger beam light A2 is used.
The light reflector 2 for use as a bar is formed in the longitudinal direction of the vehicle body, and the detection area Tp on the reflecting portion 2b on the image pickup screen is formed.
When the trigger light beam A2 is reflected in the inside, the reflection of the trigger light beam A2 is discriminated. At that time, the size of the detection region Tp depends on the required detection accuracy and detection error prevention conditions. It can be set appropriately. The configuration of the light reflector 2 is not limited to that of the embodiment, and may be, for example, a block body having a short length in the front-rear direction of the vehicle body and provided with a reflecting portion having an inclined surface in the left-right direction of the vehicle body. In this case, the starting end or the ending position of the work stroke is detected as the trigger light beam A2 is reflected somewhere on the reflecting portion of the block body.

In the above embodiment, the two light beam projecting means B1 and B2 for guiding and triggering are provided on the ground side, but the invention is not limited to this, and for example,
Only the guiding beam light projection means B1 is installed, and only the vehicle body position with respect to the guiding beam light A1 is detected, and the start or end position of the stroke is detected by other means (for example, an ultrasonic sensor or the like). It can also be configured as follows.

In the above embodiment, in the case where a plurality of work strokes are arranged in parallel, the work vehicle V is turned 180 degrees at the end of each work stroke to turn to the start end of the next work stroke. As an example, other than turning 180 degrees, for example, 9
The present invention can be similarly applied to the case of turning to 0 degrees and turning to the start end of the next work stroke.

In the above embodiment, the guiding beam light A1 is configured to be shared by a pair of adjoining steps among a plurality of work steps, and the light receiving sensor 17 for receiving the guiding beam light A1 is provided in the vehicle body. I installed it on the right side in the horizontal direction,
It may be on the left side instead of the right side. Alternatively, the guiding beam light A1 may not be shared by a pair of adjacent strokes, and one guiding beam light A1 may be projected in each work step. In this case, the light receiving sensor 17 is placed on the side of the vehicle body. It is not always necessary to provide it on one side of the direction, and it may be at the central upper position.

In the above embodiment, the present invention is applied to the work vehicle for rice planting, but it can be applied to agricultural machines other than the rice planting machine and various traveling work vehicles. The specific configuration of can be variously changed.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a block diagram of a control configuration.

FIG. 2 is a flowchart of control operation.

FIG. 3 is a flowchart of control operation.

FIG. 4 is a schematic plan view illustrating a work process and a turning motion.

FIG. 5 is a schematic side view showing a work vehicle and a guidance light beam projection state.

FIG. 6 is a schematic side view showing a main part of the position detection device.

FIG. 7 is a schematic front view showing the main part of the position detection device.

FIG. 8 is a schematic plan view showing a main part of the position detection device.

FIG. 9 is a plan view showing an image pickup screen of an image pickup means.

FIG. 10 is a plan view illustrating a turning motion.

FIG. 11 is an explanatory diagram of a set turning pattern.

[Explanation of symbols]

 B1, B2 Beam light projecting means 100 Position detecting means 1a, 1b Reflecting section 2a, 2b Reflecting section 1, Light reflecting body S Imaging means 1a, 1b Inclined surface

Claims (5)

[Claims] 1. A work vehicle provided with, on a work vehicle side, position detection means (100) for detecting a vehicle body position with respect to the light beam projected by the light beam projection means (B1, B2) installed on the ground side. A position detecting device for use with a reflector (1a, 1b, 2a, 2) for reflecting the light beam.
b) a light reflector (1, 2), and an image pickup means (S) for picking up the light reflector (1, 2) in a state in which the reflectors (1a, 1b, 2a, 2b) can discriminate. A position detecting device for a work vehicle, wherein the position detecting means (100) is configured to detect the vehicle body position based on image pickup information of the image pickup means (S). 2. A state in which the light beam is projected as a light beam for guiding along a longitudinal direction of a work stroke, and the reflecting portion (1a, 1b) of the light reflector (1) is in a lateral direction of a vehicle body. The position detecting device for a working vehicle according to claim 1, wherein the position detecting means (100) is configured to detect a position in the lateral direction of the vehicle body with respect to the guiding light beam. 3. A pair of the light reflectors (1) are juxtaposed in the vehicle front-rear direction, and the position detection means (100) is configured to detect an inclination in the vehicle front-rear direction with respect to the guiding light beam. The position detecting device for a work vehicle according to claim 2. 4. The reflection part (1) of the light reflector (1).
a, 1b) is provided with two inclined surfaces (1a, 1b) inclined respectively to the front side and the rear side of the vehicle body in order to reflect the guiding light beams projected from the front side and the rear side of the vehicle body, respectively. The position detection device for the work vehicle according to 2 or 3. 5. The light beam is projected as a light beam for trigger in a state of intersecting with the direction of the work stroke, and the position detecting means (100) uses the light beam for trigger as the light reflector (2). The position for a work vehicle according to claim 1, 2, 3 or 4, which is configured to detect a start end or an end position of the work stroke as it is reflected by the reflection portion (2a, 2b). Detection device.