Harvesting work vehicle

Abstract

To solve the problem that a configuration in which an imaging device is provided above a crawler type traveling portion cannot be used for detecting an obstacle, measuring a distance, etc. because stable imaging cannot be performed due to a change such as inclination of a vehicle.SOLUTION: A distance and a size are rationally calculated by configuring a harvesting work vehicle such that an imaging device is turned within a limited range so that the imaging device can capture a stable image, and by taking a part of the vehicle into an image.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an imaging device for an unmanned work vehicle having a crawler-type traveling unit that travels while reducing vibrations caused by unevenness in a farm field. [Background technology]

[0002] In the case of unmanned vehicles, there are systems that use image capture devices to detect obstacles from images of the front and rear, but if the field is uneven, the image capture device will shake, and if it is placed close to the traveling part, the images will be blurred, resulting in data that cannot be used for control. (Patent Document 1) [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-2478 Summary of the Invention [Problem to be solved by the invention]

[0004] In the prior art, there is a technique for detecting the height of unevenness in a farm field using a work vehicle in which imaging devices are provided at the bottom ends of both ends of the harvesting section.

[0005] However, the harvesting unit may move differently from the running unit. Also, because the harvesting unit generates more vibration than the running unit, it is possible to capture images near the field, but the images are likely to be blurred.

[0006] An object of the present invention is to provide an imaging device that is capable of dealing with vibrations and reducing image blur even when it is located in a position that is linked to a traveling unit. [Means for solving the problem]

[0007] The first aspect of the present invention is achieved by the following technical means.

[0008] The imaging device is positioned toward the front in the forward direction of the running device, and is installed at the center position of the width of the running belt of the running device.The imaging device is rotatable in a direction parallel to the axle that rotates the running belt above the running device, and the maximum downward imaging range is the range in which a part of the front of the running device is captured in the image within the rotational range of the imaging device.

[0009] The second invention is solved by the following technical means.

[0010] The imaging device is installed on the main frame of the vehicle body near the front in the forward direction of the running device, and is connected to the movement of the rocker link mechanism between the running device and the main frame, and is rotatable in a direction parallel to and perpendicular to the axle that rotates the running belt above the running device. [Effects of the Invention]

[0011] The first invention enables distance measurement from an image captured by an imaging device, thereby improving calculation speed and accuracy.

[0012] According to the second aspect of the present invention, the imaging device can be rotated up and down and left and right, and can automatically face the direction of travel. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is an overall perspective view of a work vehicle according to the present invention, seen from the left front; [Figure 2] FIG. 1 is an overall perspective view of a work vehicle according to the present invention, seen from the left rear; [Figure 3] Overall view of the work vehicle of the present invention from the front [Figure 4] FIG. 1 is an overall perspective view of a work vehicle according to the present invention, seen from the left front; [Figure 5] Overall view of the work vehicle of the present invention from the front DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described below with reference to the embodiments shown in the drawings.

[0015] The work vehicle shown in FIGS. 1 to 5 shows an example of this embodiment.

[0016] The work vehicle of the present invention will now be described.

[0017] This is a general-purpose electric unmanned vehicle, also known as a robotic work vehicle, used in field farming. Field farming does not become muddy like paddy fields, but the soil is often ridged and soft to make it easier for root vegetables to grow. Because it contains a lot of moisture, wheels can slip when traveling on wheels, so a crawler-type vehicle is preferred.

[0018] However, because the crawler-type running gear is long from front to back, it can tilt significantly forward and backward when the field is uneven. The left-right tilting also causes not only the vehicle body to tilt but also twisting, which can cause the implement to miss its target position, resulting in uncultivated land during tilling work and the inability to retrieve crops during harvesting work. Twisting of the main frame also weakens the vehicle's durability.

[0019] To address these issues, a rocker link mechanism is used between the running part and the main frame to absorb vibrations and twisting.

[0020] Furthermore, the working machine of the present invention is an unmanned work vehicle. Therefore, it uses an imaging device to analyze images to avoid obstacles and secure harvested crops. However, even if the image accuracy of the imaging device is improved, there is a problem in that image blurring makes analysis impossible. In addition to a vibration reduction configuration for the traveling section, the present invention is configured to address the problem of the imaging device.

[0021] The configuration of the crawler assembly and rocker link mechanism, which are the traveling devices of the work vehicle of the present invention, will be described with reference to Figs.

[0022] The traveling device is composed of a left crawler assembly 30 and a right crawler assembly 50, which are separately formed as left and right units. In the left crawler assembly 30, the left swing arm 21 and left link rod 22 are connected to a boss hole 23A on the left side of the rocker arm 23. In the left crawler assembly 50, the right swing arm 27 and right link rod 28 are connected to a boss hole 23B on the right side of the rocker arm 23. Bearings are fitted into the left and right boss holes, allowing the left link rod 22 and right link rod 28 to rotate relative to the rocker arm 23 on plane B, which is parallel to the ground. In this way, the left and right crawler assemblies twist via the left and right link rods and left and right rocker arms to form a crawler traveling body that ensures ground contact.

[0023] At the centre of rocker arm 23, on plane A perpendicular to plane B parallel to the ground, there is a boss hole 23C on the side facing the direction of travel of the work vehicle, and there is a bearing inside, into which shaft 24A extending from one end of connecting link plate 24 is inserted, allowing link plate 24 to rotate on plane A perpendicular to the ground. The other end of link plate 24 is joined to main body frame 10 of work vehicle 1, and link plate 24 can rotate main body frame 10 on plane B parallel to the ground.

[0024] The left swing arm 21, left link rod 22, rocker arm 23, right link rod 28, and swing arm 27 are arranged in a series that can move freely in both horizontal and vertical directions relative to the ground surface. As a result, the left crawler assembly 30 and the right crawler assembly 50 can move freely in both horizontal and vertical directions independently relative to the ground surface, allowing them to twist to accommodate vibrations while maintaining contact with the ground in response to unevenness in the field.

[0025] Each joint is a bearing mechanism, but it may be one that reduces rotational resistance to an absolute minimum, and by providing a certain degree of rotational load, it is possible to absorb and mitigate minute movements, thereby achieving an anti-vibration effect.

[0026] Of these, by applying a rotational load to each bearing section, the left swing arm 21, left link rod 22, rocker arm 23, right link rod 28, and swing arm 27 are configured in series to form a link mechanism that can be used as a power transmission configuration, a frame configuration for the work vehicle itself, and a vibration reduction configuration; this is also a rocker link mechanism or rocker bogie mechanism, and in the present invention is referred to as rocker link mechanism 20.

[0027] Rocker link mechanism 20 rotates about boss hole 23C relative to plane A, which is perpendicular to the ground surface, and rotates about boss holes 23A and 23B relative to plane B. If plane C is defined as a plane that follows the side of the work vehicle and intersects planes A and B perpendicularly, the joint between left swing arm 21 and left link rod 22 is joined by a universal joint, and can rotate in multiple directions by joint ball 22A. The joint between right swing arm 27 and right link rod 28 is also joined by a universal joint, and can rotate in multiple directions by joint ball 28A. This universal joint can be used to tilt work vehicle 1 forward or backward, and can also be used to adjust vehicle height.

[0028] A working mechanism 60 is connected to the center of the main body frame 10. A parallel frame 62 is placed between a left support frame 61 and a right support frame 63, forming a portal frame. The left and right support frames are mechanisms that rotate within a predetermined range with respect to plane C at joints 61A and 63A.

[0029] A slide rail 64 is provided in front of the parallel frame 62. Although not shown in the figure, the slide rail 64 is a mechanism that can rotate at the center of the parallel frame 62, and is a mechanism that allows the work vehicle 1 to face horizontally relative to the ground even if it tilts in the rotation direction on plane A.

[0030] As shown in Figure 3, a forward-facing working machine 70 is attached to the slide rail 64. The working machine 70 is a robotic hand, but it can also be a harvesting device with a reaping section, and various working machines can be attached, and by moving it in line with the slide rail 64 inside the working mechanism 60, which is a gate-shaped frame, it is possible to perform optimal work.

[0031] The mounting position of the imaging device on the work vehicle of the present invention will be described with reference to FIGS. 1, 2 and 3. FIG.

[0032] A mounting plate 32 for a traveling motor 31, which provides the driving force for the left crawler assembly 30, is located inside the work vehicle 1, and transmits power to an axle 34 via a belt 33. The axle 34 rotates drive wheels 35, which in turn rotate a traveling belt 36 to provide traveling power. The traveling belt may be a lug-type belt as shown in the figure, or may be an omniwheel with oval-shaped ends. The traveling motor 31 is located above the traveling belt 36.

[0033] Similarly, a mounting plate 52 for a traveling motor 51, which provides the driving force for the right crawler assembly 50, is located inside the work vehicle 1, and power is transmitted to an axle 54 by a belt 53. The axle 54 rotates a driving wheel 55, which in turn rotates a traveling belt 56 to provide traveling power. The traveling motor 51 is located above the traveling belt 56.

[0034] In this way, the left and right travel motors are arranged on the left and right travel belts, so they do not get in the way when work equipment is placed inside the rear of the work vehicle 1. Conversely, if the left and right motors are placed outside the work vehicle 1, they will extend beyond the width of the vehicle body, so there will be no problem of them interfering with work.

[0035] An imaging device 90 is provided above the running belt 36, and an imaging device 100 is provided above the running belt 56. The running belt 36 has a width 36A, and an imaging unit center 91A, which is the center of an imaging unit 91 in the imaging device, is located on a line at the center position of the belt width. The running belt 56 has a width 56A, and an imaging unit center 101A, which is the center of an imaging unit 101 in the imaging device, is located on a line at the center position of the belt width.

[0036] The front of the work vehicle 1 is the side where the rocker link mechanism 20 and the slide rail 64 for mounting the work equipment are located. In FIG. 1 , the direction in which the imaging devices 90 and 100 are facing is the forward direction. The imaging devices are located on the front side of the work vehicle 1, facing the forward direction, and are positioned so that the situation ahead can be easily confirmed with the imaging devices. Naturally, capturing images of the parts of the running belts 36 and 56 that come into contact with the field in the forward direction is important to ensure safe driving. Therefore, they must be located on the front side of the work vehicle 1. Furthermore, capturing images of a portion of the running belts simultaneously provides the advantage of clarifying their positional relationship. However, if they are located in the center or rear of the work vehicle 1, they may be shaded by the long running belts, making it impossible to detect obstacles. Raising the imaging devices would solve this problem, but the higher they are raised, the greater the shaking of the imaging devices, making it difficult to capture stable images. Therefore, they must be located at the minimum necessary height.

[0037] The imaging unit 91 and the running belt 36 in the imaging device are spaced apart by a distance equal to or greater than the distance it takes for the imaging unit 91 to make one rotation. For example, even if the imaging unit 91 rotates once due to poor rotation control, it will not interfere with the running belt 36. Furthermore, because of this space, even if mud or the like is bounced off the running belt 36, problems such as the mud adhering to the imaging unit 91 and making it impossible to capture images will not occur. Even if foreign matter such as mud gets on the running belt 36, it will not interfere with the imaging unit 91, so problems such as a change in the imaging direction will not occur. The imaging device 100 has a similar configuration to the imaging device 90 and exhibits similar effects.

[0038] The left and right imaging devices maintain a distance from the running belt to prevent splashing mud and other debris. This distance is also used to adjust the vertical angle of the imaging devices. The rotation axis 93 of the imaging unit 91 is parallel to the axle 34, and the rotation axis 103 of the imaging unit 101 is parallel to the axle 54. Furthermore, by aligning the imaging units with the center of the width of the running belt as described above, images are captured from the center of the running belt and limited to images moving vertically from this position. Therefore, if the imaging devices have a distance measurement function, the distance to obstacles can be easily calculated. The imaging device 90 is located toward the front of the vehicle in the forward direction of travel of the left crawler assembly 30. Furthermore, by locating it at the center of the width of the running belt 36, which is the running belt, the center line of the left crawler assembly 30 can be accurately confirmed, enabling reliable detection of even small obstacles on the crawler's running path. This configuration is also the same for the right crawler assembly 50.

[0039] In the first invention, the imaging device 90 is positioned toward the front in the forward direction of the left crawler assembly 30 (the traveling device), and the imaging center 91A of the imaging unit 91 is located at the center of the traveling belt width 36A. The imaging device 90 is rotatable above the left crawler assembly 30 in a direction parallel to the axle 34 that rotates the traveling belt 36. The imaging device 90 does not interfere with the traveling belt 36 during one rotation, which is its rotational range. Furthermore, within its rotational range for imaging, a portion of the front of the left crawler assembly 30 (the traveling device) is captured in the image captured by the imaging device. This allows the manager to easily grasp the distance between the vehicle and an obstacle ahead during remote work. In other words, while it is important that a portion of the vehicle is captured simultaneously in the captured image, if a portion of the vehicle must always be included, capturing images above or far from the field becomes difficult. Therefore, when an obstacle or the like is discovered, the imaging device is rotated at that position until a portion of the front of the traveling device, which is part of the vehicle, is captured in the image, and the captured image can be used to calculate the distance to the obstacle. Constantly capturing a portion of the front of the traveling device limits the imaging range and image resolution, which also affects the accuracy of analyzing the captured object. Therefore, changing the imaging direction as needed to capture a portion of the front of the traveling device and then performing comparison and calculations increases processing power and improves accuracy, which is rational. Furthermore, by setting the range in which a portion of the front of the traveling device is captured in the image as the maximum lower imaging range, it also becomes the lower limit of the imaging range, and by rotating the imaging device within the minimum necessary range, unnecessary rotation is eliminated, enabling rapid image processing.

[0040] Although the explanation was given for the left-hand running section, the processing is the same for the right-hand side. As the imaging devices are located on the left and right crawlers, they can be used as stereo cameras, and three-dimensional shape and dimensions can also be detected. In particular, as each imaging device is located on the running line, installing them in front captures the width of the vehicle, and even slight collapses in the ridges at the edge of the paddy fields can be detected by imaging, allowing work to be carried out safely.

[0041] Although the present invention has been described using a lug belt used in rice paddy combine harvesters as a representative example, it can also be used with an omniwheel (omni-crawler, mecanum crawler) with oval ends. A feature of this is the continuous circular cross-section crawler.

[0042] In the technology for capturing images of parts of the running gear, which is the first invention, the shape of the running belt has a significant impact on the calculation. In the case of a raku belt, the imaging pitch of the lugs is counted, and this is used to calculate the running speed and to compare the lug height to calculate the distance to an obstacle. Since an omniwheel does not have clear protrusions like lugs, the cross-sectional changes of the belt and the movement of the internal chain are counted at the bending points to make a judgment.

[0043] The imaging devices 90 and 100 have imaging units 91 and 101 that can swing up and down, so that the camera lines of sight can be configured to face in the same direction as the left and right crawler assemblies swing. A rotation shaft 93 is provided between the imaging unit 91 and the fixed guide 92, and a rotary damper is installed inside the axis of the rotation shaft 93, so that rotation is smooth even if a sudden change in rotation occurs. The imaging device 100 has a similar configuration. As a result, even if the left and right crawler assemblies swing differently on the left and right, the left and right imaging units rotate slowly so that the camera lines of sight face in the same direction, which also serves as a vibration countermeasure.

[0044] One technique for facing in the same direction is to use the principle of a pendulum, and in this embodiment, motors 94 and 104 are used to control rotation so that the camera faces perpendicular to the ground. Furthermore, the rotation control allows for any angle to be changed, so the line of sight can be set according to the application.

[0045] As explained above, imaging unit 91 and imaging unit 101 have a clearance dimension that does not interfere with the crawler assembly even when rotating once. However, if motors 94 and 104 are used, the rotation range can be limited so that even when set facing downwards, the front end of the crawler assembly does not block the imaging field of view of the imaging device.

[0046] It is also possible to provide an inertial measurement device on each of the left and right crawler assemblies and tilt the imaging device in a direction corresponding to the tilt direction of the crawler.

[0047] When the difference in field of view between the left and right imaging devices becomes too large, such as when going over a large step, the cameras are raised and lowered so that their fields of view overlap, reducing stereo parallax.

[0048] Fixed guides 92 and 102 for the left and right imaging devices are connected to subframes 45 and 47, respectively, to reinforce the left and right crawler assemblies against twisting. They also protect imaging units 91 and 101. The upper parts of the left and right subframes act as awnings, making the structure less susceptible to the effects of sunlight and the like.

[0049] The rotation control of the imaging device will be described.

[0050] With the paved position as the reference, imaging units 91 and 101 are set to the same phase, and the relationship between the inertial measurement unit and its vertical position relative to the ground is also corrected as a reference. The vehicle then enters the field, drives to work, and takes fixed images for a while. This is to detect the basic amplitude of shaking. The amplitude of shaking in this captured image is the basic amplitude of shaking in the field being worked on, and image analysis is possible within the range in which this amplitude can be corrected, but it is also possible to correct this amplitude by using rotation control.

[0051] When crossing a ridge, the angle must be changed significantly, and the imaging device cannot keep up with it. Therefore, the imaging device may enter a fixed mode and be controlled to protect the imaging device.

[0052] There is also a method to correct the orientation of the imaging device depending on the orientation of the vehicle body. When the work vehicle is equipped with a work implement at the rear and works forward, the rear of the vehicle sinks and the front is raised, so the imaging device is controlled to tilt to match this standard inclination.

[0053] 4 and 5 show a configuration in which the imaging devices are attached to the left and right sides of the main body frame 10. In this configuration, the imaging unit is not located above the crawler assembly, so extreme shaking does not occur, and compared to a configuration in which the imaging unit is located on the crawler assembly, it is possible to stably keep the imaging unit horizontal to the ground without having to frequently and significantly change its angle.

[0054] The imaging unit 111 is rotated by a motor 112 and held by a stay 113, and the pivot 115, which is the center of rotation of the stay 113, is joined to the main body frame 10 via a flexible resin block 114. This allows the pivot 115 to move in many directions, and the axial position of the pivot 115 can be moved, although within a limited range, like a universal joint. With this configuration, the pivot 115 moves in conjunction with the movement of the left link rod 22, and by changing the orientation of the stay 113, the imaging unit 111 can be moved left and right.

[0055] The imaging unit 111 is rotated up and down by a motor 112 and moved left and right in conjunction with the movement of the left link rod 22. This movement enables imaging perpendicular to the traveling direction and horizontal to the ground.

[0056] This configuration is similar to that of the imaging 121.

[0057] The imaging unit 121 is rotated by a motor 122 and held by a stay 123, and the pivot 125, which is the center of rotation of the stay 123, is joined to the main body frame 10 via a flexible resin block 124. This allows the pivot 125 to move in many directions, and the axial position of the pivot 125 can be moved, although within a limited range, like a universal joint. With this configuration, the pivot 125 moves in conjunction with the movement of the left link rod 28, and by changing the orientation of the stay 123, the imaging unit 121 can be moved left and right. This left and right change is rotation perpendicular to the axle.

[0058] In the second invention, the imaging devices 111 and 121 are installed on the main frame 10 of the vehicle body near the front in the forward direction of the running device, and are connected to the movement of the rocker link mechanism 20 between the running device and the main frame 10, and can rotate in a direction parallel to and perpendicular to the axle that rotates the running belt above the running device.

[0059] There is a way to install a satellite positioning device or an inertial measurement unit on top of the imaging device. This will allow the precise orientation and tilt of each imaging device to be determined, and the orientation of the image to be determined can be used for driving control or to obtain detailed data for automatic driving control along the edges of rice paddies. [Explanation of symbols]

[0060] 1 Work vehicle 10 Main frame 22 Link rod left 30 Left crawler assembly 45 subframe 47 Subframe 90 Imaging Device 91 Imaging unit 92 Fixed guide 93 Rotation axis 94 Motor 111 Imaging device 112 Motor 113 Stay 114 Resin Block 115 Rotating shaft

Claims

1. The imaging device is disposed forward in the forward direction of the traveling device, and is provided at the center position of the width of the traveling belt of the traveling device; the imaging device is rotatable above the traveling device in a direction parallel to the axle that rotates the traveling belt; A work vehicle in which the maximum lower imaging range is the range in which a part of the front of the traveling device is captured in the image within the rotational range of the imaging device.

2. The imaging device is installed on a body frame of the vehicle body near the front in the forward direction of the traveling device, A work vehicle that is connected to the movement of a rocker link mechanism between the running gear and the main frame and is capable of rotating in a direction parallel to and perpendicular to the axle that rotates the running belt above the running gear.

Images