combine

Abstract

To provide a combine harvester capable of appropriately evaluating the risk of manual threshing work.SOLUTION: A combine harvester includes a thresher (4) configured to thresh grain culms, a feed chain (4B) configured to feed the grain culms to the thresher (4), a camera (103104) and a ranging device (105) configured to monitor manual threshing work of a worker, and a work state estimation device (120) configured to evaluate a degree of risk of work of the worker from an image captured by the camera (103104) and distance information obtained by the ranging device (105). The camera (103104) is disposed above the grain culm conveying height of the feed chain (4B), and the distance measuring device (105) is disposed below the grain culm conveying height of the feed chain (4B).SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a combine harvester.

Background Art

[0002] Conventionally, a combine harvester provided with a camera for imaging a handling work part to evaluate the risk of handling work is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, although it is described that it is determined by image analysis processing that an operator has moved backward from a handling position for a predetermined time, since only the moving time is evaluated, it cannot be said that it is sufficient as an evaluation of risk, and there is room for great improvement.

[0005] Therefore, a main object of the present invention is to provide a combine harvester capable of appropriately evaluating the risk of handling work.

Means for Solving the Problems

[0006] The present invention that solves the above problems is as follows.

[0007] That is, the invention according to claim 1 includes a threshing device (4) for threshing grain straws, a feed chain (4B) for supplying the grain straws to the threshing device (4), cameras (103, 104) for monitoring the handling work of an operator, a distance measuring device (105), and a working state estimation device (120) for evaluating the risk level of the operator's work from the video taken by the cameras (103, 104) and the distance information obtained by the distance measuring device (105). The work state estimation device (120) has a posture estimation unit (122) that estimates the posture of the worker's body from the position information of specific parts of the worker's body identified from the video and the distance information from the distance measuring device (105), and also evaluates the degree of risk of the posture. This combine harvester is characterized by the following features.

[0008] The invention described in claim 2 is the combine harvester according to claim 1, wherein the cameras (103, 104) are positioned above the height of the grain stalks being transported by the feed chain (4B), and the distance measuring device (105) is positioned below the height of the grain stalks being transported by the feed chain (4B).

[0009] The invention described in claim 3 is, The work state estimation device (120) is capable of evaluating the degree of risk of work using the estimation results of the posture estimation unit (122) and evaluating the degree of risk of work without using the estimation results of the posture estimation unit (122), as described in claim 1 or claim 2. That is the case. [Effects of the Invention]

[0011] According to the present invention, the safety of manual handling operations can be appropriately evaluated. [Brief explanation of the drawing]

[0012] [Figure 1] This is a left side view of a combine harvester. [Figure 2] This is a right side view of a combine harvester. [Figure 3] This is a perspective view of the cabin frame that covers the control section. [Figure 4] This is a left side view of the cabin frame. [Figure 5] This is a right-side view of the cabin frame. [Figure 6] This is a front view of the cabin frame. [Figure 7] This is a plan view showing a cross-section of the cabin in the horizontal direction. [Figure 8] This is a front view of the cabin. [Figure 9] This is a left side view of the cabin. [Figure 10] This is a rear view of the cabin. [Figure 11] This is a right-side view of the control panel. [Figure 12] This is a plan view of the left side of the control panel. [Figure 13] This is a right-side view of the control panel's side panel. [Figure 14]It is an explanatory diagram showing a control device for a combine harvester.

Embodiments for Carrying out the Invention

[0013] As shown in FIGS. 1 and 2, the combine harvester is provided with a traveling device 2 consisting of a pair of left and right crawlers that travel on the soil surface below the machine body frame 1, a harvesting device 3 for harvesting cereal straw in the field is provided in front of the machine body frame 1, a threshing device 4 for threshing and sorting the harvested cereal straw is provided on the left rear side of the harvesting device 3, and an operator's cab 5 for the operator to board is provided on the right rear side of the harvesting device 3.

[0014] An engine room 6 for mounting an engine E is provided below the cab 5, a grain tank 7 for storing the threshed and sorted grains is provided on the rear side of the cab 5, and a discharge auger 8 consisting of a vertical elevating part for discharging the grains to the outside and a horizontal discharge part extending in the front-rear direction is provided on the rear side of the grain tank 7. Further, the cab 5 is covered with a cabin 9 equipped with a lighting light at the upper part.

[0015] As shown in FIG. 3, the frame 10 forming the cabin 9 is formed by a left frame 11, a right frame 12, a rectangular connecting frame (also referred to as "first connecting frame") 13 connecting the front parts of the left frame 11 and the right frame 12, and a plurality of connecting frames (also referred to as "second connecting frames") extending in the left-right direction and connecting the rear parts of the left frame 11 and the right frame 12.

[0016] As shown in FIG. 4, the left frame 11 is formed by left vertical frames 15A to 15D extending in the vertical direction and left front-rear frames 16A to 16E extending in the front-rear direction. In this specification, the left vertical frames 15A to 15D are collectively referred to as the left vertical frame 15, and the left front-rear frames 16A to 16E are collectively referred to as the left front-rear frame 16.

[0017] The left front and rear frame 16A is connected to the upper parts of the left upper and lower frame 15A and the left upper and lower frame 15D, with its front part extending forward of the left upper and lower frame 15A. The left front and rear frame 16B is connected to the upper part of the left upper and lower frame 15A and the upper part of the left upper and lower frame 15A.

[0018] The left front and rear frame 16C is connected to the middle section of the left upper and lower frame 15A and to the lower sections of the left upper and lower frame 15C and the left upper and lower frame 15D. The left front and rear frame 16D is connected to the lower middle section of the left upper and lower frame 15A and to the middle section of the left upper and lower frame 15B, and extends further rearward than the left upper and lower frame 15B. The left front and rear frame 16E is connected to the lower sections of the left upper and lower frame 15A and the left upper and lower frame 15B, with its front section extending further forward than the left upper and lower frame 15A and its rear section extending further rearward than the left upper and lower frame 15B. This increases the rigidity of the left frame 11 and suppresses deformation of the left frame 11.

[0019] As shown in Figure 5, the right frame 12 is formed from upper and lower right frames 17A to 17C that extend in the vertical direction, right front and rear frames 18A and 18B that extend in the front and rear direction, and a right curved frame 19 that connects the lower part of the upper and lower right frame 17C and the rear part of the right front and rear frame 18B.

[0020] In this specification, the upper right and lower frames 17A to 17C are collectively referred to as the upper right and lower frames 17, and the right front and rear frames 18A and 18B are collectively referred to as the right front and rear frames 18.

[0021] The right front and rear frame 18A is connected to the upper parts of the upper right and lower right frame 17A and the upper right and lower right frame 17B, with its front portion extending forward of the upper right and lower right frame 17A. The right front and rear frame 18B is connected to the lower parts of the upper right and lower right frame 17A and the right curved frame 19. In addition, the upper right and lower right frame 17B is connected to the rear front portion of the right front and rear frame 18A and the right curved frame 19. This increases the rigidity of the right frame 12 and suppresses deformation of the right frame 12.

[0022] As shown in Figures 4 and 5, the left connecting frame 13L, which extends in the front-rear direction of the connecting frame 13, is connected to the lower parts of the left upper-lower frame 15A and the left upper-lower frame 15B. The right connecting frame 13R, which extends in the front-rear direction of the connecting frame 13, is connected to the lower parts of the right upper-right lower frame 17A and the right curved frame 19. In addition, the connecting frame 14 is connected to the rear of the left front-rear frame 16C and the right curved frame 19. This firmly connects the left frame 11 and the right frame 12, increasing the rigidity of the frame 10 and suppressing deformation of the frame 10.

[0023] The upper part of a rectangular storage box 20, which has an open top, is fixed to the inner circumference of the connecting frame 13. The storage space of the storage box 20 houses a battery 20A, a pump 20B, etc., and a step-like step (not shown) for use by workers when ascending or descending is attached to an opening formed in the right wall of the storage box 20.

[0024] At the rear of the frame 10, a partition member 21 is provided that separates the control unit 5 from the engine room 6. At the front of the partition member 21, a support member 22 is provided to support the cockpit used by the operator. On the left side of the partition member 21, a protrusion 23 is formed by bending the partition member 21 upward, leaving the left and bottom sides open. This allows the front part of the exhaust gas purification device (DPF), which purifies impurities contained in the exhaust gas emitted from the engine E, to be positioned within the protrusion 23.

[0025] The partition member 21 is formed from a portion 21A extending upward from a lower end detachably fixed to the rear of the connecting frame 13, a portion 21B extending upward and rearward from the upper end of portion 21A, a portion 21C extending gently upward and rearward from the upper end of portion 21B, a portion 21D extending upward from the upper end of portion 21C, and a portion 21E extending upward and rearward from the upper end of portion 21D. The rear end of portion 21E is detachably fixed to the connecting frame 14.

[0026] As shown in Figure 6, the left upper and lower frame 15A extends upward from its lower end connected to the connecting frame 13, then curves upward to the left, and then curves upward again before extending upward. Similarly, the left upper and lower frame 15B extends upward from its lower end, then curves upward to the left, and then curves upward again before extending upward. This allows for the creation of a large space to the left of the cockpit of the control unit 5, reducing stress on the operator caused by the cramped space. The right upper and lower frame 17A also extends upward from its lower end connected to the connecting frame 13.

[0027] The left frame 11 is provided with a plate-shaped left wall 25, which is formed from a portion 25A that extends downward along the left frame 11, a portion 25B that extends downward to the right from the lower end of portion 25A, and a portion 25C that extends downward from the lower end of portion 25B.

[0028] A rectangular opening (not shown) is provided in the upper part of section 25A, and the lower end of section 25C abuts against the connecting frame 13. In addition, a plate-shaped cover member 26 is provided on the lower part of section 25A, section 25B, and the section facing section 25C, extending upward and to the left from the upper surface of the connecting frame 13.

[0029] The right frame 12 is provided with a plate-like right wall 27, and a rectangular opening formed at the top of the right wall 27 is provided with a window (not shown).

[0030] As shown in Figures 7-10, a support portion (also called the "first support portion") 30 is provided on the lower side of the front connecting frame 13A of the connecting frame 13, and is located at the front of the aircraft frame 1. The support portion 30 is formed from left and right support members 30A that extend in the left-right direction and are located on the lower side of the front connecting frame 13A, a left upper and lower support member 30L that extends from the left side of the left and right support members 30A to the aircraft frame 1, and an upper and lower right support member 30R that extends from the right side of the left and right support members 30A to the aircraft frame 1. The support portion 30 is located in front of the output shaft 36A of the transmission 36.

[0031] The lower surface of the front connecting frame 13A and the upper surfaces of the left and right support members 30A are connected via a pair of vibration-damping members (also called "first vibration-damping members") 31, such as vibration-damping rubber or shock absorbers, which are provided at a predetermined distance apart in the left-right direction. This suppresses the transmission of vibrations generated in the aircraft frame 1 during driving, etc., to the front connecting frame 13A via the left and right support members 30A, thereby suppressing the shaking of the cabin 9.

[0032] Furthermore, an oil filter 33 is installed in the middle of the lower surface of the left and right support members 30A to remove impurities from the oil supplied to the hydraulic continuously variable transmission 32 that increases and decreases the output speed of the engine E. This makes it easy to route the flexible hose connecting the continuously variable transmission 32 and the oil filter 33.

[0033] A support portion (also called the "second support portion") 35 is provided on the lower side of the left front and rear frame 16D, and is located at the front of the aircraft frame 1. The support portion 35 is formed from a front and rear support member 35A that extends in the front-rear direction and is located on the lower side of the left front and rear frame 16D, a front upper and lower support member 35F that extends from the front of the front and rear support member 35A to the transmission 36 that increases and decreases the output rotation of the continuously variable transmission 32 located at the front of the aircraft frame 1, and a rear upper and lower support member 35B that extends from the rear of the front and rear support member 35A to the transmission 36. This makes it possible to shorten the lengths of the front upper and lower support member 35F and the rear upper and lower support member 35B to increase the rigidity of the support portion 35 and prevent deformation of the support portion 35.

[0034] The lower surface of the left front and rear frame 16D and the upper surface of the front and rear support member 35A are connected via vibration-damping members (also called "second vibration-damping members") 37, such as vibration-damping rubber or shock absorbers. This suppresses the transmission of vibrations generated in the aircraft frame 1 during driving, etc., to the left front and rear frame 16D via the front and rear support member 35A, thereby suppressing the shaking of the cabin 9.

[0035] Below the connecting frame 14, a support portion (also called the "third support portion") 38 is provided, which is located at the rear of the front side of the aircraft frame 1. The support portion 38 is formed from left and right support members 38A that extend in the left-right direction and are located below the connecting frame 14, a left upper and lower support member 38L that extends from the left side of the left and right support members 38A to the aircraft frame 1, and an upper and lower right support member 38R that extends from the right side of the left and right support members 38A to the aircraft frame 1. In addition, the upper lower parts of the left upper and lower support member 38L and the upper and lower right support member 38R are provided with left and right reinforcing members 38D that extend in the left-right direction. This increases the rigidity of the support portion 38 and prevents deformation of the support portion 38.

[0036] The lower surface of the connecting frame 14 and the upper surfaces of the left and right support members 38A are connected via a pair of vibration-damping members (also called "third vibration-damping members") 39, such as vibration-damping rubber or shock absorbers, which are provided at a predetermined distance apart in the left-right direction. This suppresses the transmission of vibrations generated in the aircraft frame 1 during travel, etc., to the connecting frame 14 via the left and right support members 38A, thereby suppressing the shaking of the cabin 9.

[0037] In a plan view, vibration-damping members 31, 37, and 39 are provided in order from the front. Vibration-damping member 37 is located to the left of vibration-damping members 31 and 39, and is positioned at the center of the transmission 36 in the left-right direction. Vibration-damping members 39 are offset to the left of vibration-damping member 31; that is, the left vibration-damping member 39 is located to the left of the left vibration-damping member 31, and the right vibration-damping member 39 is located to the left of the right vibration-damping member 31. Furthermore, the distance between the left vibration-damping member 39 and the right vibration-damping member 39 is wider than the distance between the left vibration-damping member 31 and the right vibration-damping member 31.

[0038] It is preferable to use larger vibration-damping rubber for vibration-damping members 37 and 39 than for vibration-damping member 31. This makes it possible to suppress vibrations of the left front and rear frame 16D and the connecting frame 14, which have larger amplitudes due to vibrations in the front-rear and left-right directions than the front connecting frame 13A.

[0039] In a side view, vibration damping member 31 is positioned above the transmission 36, vibration damping member 37 is positioned above vibration damping member 31, and vibration damping member 39 is positioned above vibration damping member 37. It is preferable to position vibration damping member 37 on a virtual line connecting vibration damping member 31 and vibration damping member 39. This further suppresses the transmission of vibrations generated in the aircraft frame 1 during driving, etc., to the frame 10 via the left and right support members 30A, front and rear support members 35A, and left and right support members 38A, thereby further suppressing the shaking of the cabin 9, and also allows for rapid attenuation of vibrations transmitted to the frame 10.

[0040] As shown in Figure 11, a rectangular opening 41 for maintenance work is formed in the lower front part of the right wall of the cabin 9, opposite the parking brake pedal 40 that brakes the running gear 2. This allows for easy maintenance of the parking brake pedal 40 through the opening 41. Normally, the opening 41 is covered with a rectangular cover 42.

[0041] As shown in Figures 12 and 13, a front panel 45 is provided on the front side of the cockpit of the control unit 5, and a side panel 50 is provided on the left side.

[0042] The front panel 45 is equipped with a monitor 46 that displays the travel speed of the travel device 2 and the output rotation of the engine E. To the right of the monitor 46 are operating levers (not shown) for turning the travel device 2 and raising and lowering the harvesting device 3.

[0043] The left side of the side panel 50 is located close to the left front and rear frame 16D that supports the left wall of the cabin 9. The front of the side panel 50 is a gear shift lever 51 for operating the continuously variable transmission 32, and behind the gear shift lever 51 is an emergency stop switch (also called a "switch") 52 for emergency stopping the engine E, and to the right of the emergency stop switch 52 is a harvesting lever 53 for operating the harvesting clutch that transmits the output rotation of the engine E to the harvesting device 3 and the threshing clutch that transmits it to the threshing device 4.

[0044] The emergency stop switch 52 is located in a recess 55 of the side panel 50, and the upper part of the emergency stop switch 52 is positioned approximately flush with the top surface of the side panel 50. This prevents the emergency stop switch 52 from being accidentally pressed.

[0045] In a side view, the front wall of the recess 55 is formed with an upward slope towards the front, and the rear wall is formed with an upward slope towards the rear. In the front-rear direction, the emergency stop switch 52 is positioned behind the grip portion of the mowing lever 53 when it is moved forward and in a forward-leaning position, and behind the grip portion of the mowing lever 53 when it is moved backward and in a rearward-leaning position. This allows the emergency stop switch 52 to be quickly pressed in the event of engine E overheating or other issues.

[0046] The rear of the side panel 50 is equipped with a power port 71 that draws power from the vehicle's battery into the cabin 9. This power port 71 is of the USB (Universal Serial Bus) type and supplies power to portable information terminals and other devices carried by the worker.

[0047] Furthermore, a power steering lever is provided on the front right side of the cabin 9. This power steering lever raises and lowers the harvesting device 3 by moving it forward and backward, and steers the machine by moving it left and right. A camera that captures images of the area in front of the machine is mounted on the front upper part of the cabin 9. This camera is used for viewing by managers who can check the work status remotely, or for image analysis by evaluation systems such as machine learning. However, with this type of camera, when the machine is steered, it is not possible to photograph the destination intended by the operator until the direction of travel of the machine actually changes, so there is room for improvement in terms of convenience as a means of confirmation. For this reason, when the power steering lever is operated, it is preferable to rotate the optical axis of the camera in the direction of the power steering lever operation according to the angle and duration of the operation. Conversely, it is also possible to rotate it in the opposite direction to the direction of the power steering lever operation.

[0048] Next, the manual threshing section will be explained. The manual threshing section is the part where the worker supplies the hand-cut grain stalks to the threshing device 4. More specifically, the front part of the feed chain 4B that supplies the grain stalks to the threshing device 4 has a conveying mechanism exposed upwards in the area in front of the front wall 4A of the threshing device 4. Therefore, the area in front of the threshing device 4, from the front wall 4A of the threshing device 4 to the front end of the feed chain 4B, is the manual threshing section.

[0049] The manual threshing (pillow threshing) operation, in which grain stalks are fed into this manual threshing unit, is dangerous if clothing or the human body comes into contact with the fast-moving feed chain 4B. Therefore, the work vehicle control device 110 (Figure 14) executes controls to ensure the safety of the feed chain 4B and other components when a dangerous event occurs during the operation.

[0050] The input interface of the work vehicle control device 110 is connected to an emergency stop switch 101, a harvesting unit clutch sensor 102, and the like.

[0051] The output interface of the work vehicle control device 110 is connected to the engine control device 131, the harvesting clutch 132, the threshing clutch 133, the warning output device 134, the threshing drum cover release mechanism 135, and the like.

[0052] Furthermore, a work state estimation device 120 is also connected to the work vehicle control device 110. The work state estimation device 120 is connected to a first camera (also called "camera") 103 and a second camera (also called "camera") 104, and is capable of receiving captured images as input. In addition, a LIDAR device (also called "distance measuring device") 105 is connected to the work state estimation device 120. The LIDAR device 105 is a known optical detection distance measuring device and can be replaced with other distance measuring devices as long as it can three-dimensionally search for the distance to the surrounding environment.

[0053] The emergency stop switch 101, although not shown in detail in the illustration, is located on the left outer surface of the front of the threshing device 4 and is operated when the operator senses danger. The harvesting clutch sensor 102 detects the engagement status of the harvesting clutch, which is located in the transmission path from the engine E to the harvesting device 3.

[0054] Although the engine control device 131 is described as being connected to the output interface for convenience, in reality it is connected to the work vehicle control device via a so-called CAN connection, communicating command signals and other information, acquiring engine E status data, and controlling rotational speed, etc. The harvesting clutch 132 and the threshing clutch 133 connect and disconnect the power of the engine E to the harvesting device 3 and the threshing device 4. The warning output device 134 notifies the manual threshing operator of dangerous situations, and although its installation location is arbitrary, it is preferably installed around the front of the threshing device 4. The threshing drum cover release mechanism 135 is installed on the top of the threshing device 4 and is an actuator for forcibly opening the threshing drum cover that covers the upper half of the threshing drum. Since the threshing drum cover is fitted with a clamping rod that opposes the upper side of the feed chain 4B, opening the threshing drum cover exposes the upper half of the threshing drum and releases the gripping of the grain stalks by the feed chain 4B.

[0055] The first camera 103 and the second camera 104, connected by wire or wirelessly to the work state estimation device 120, are both cameras for imaging the area around the hand-threshing work area. The first camera 103 is fixed to the left frame 11 at the lower left side of the cabin 9. The first camera 103 is installed with its optical axis facing left to right, and it images the area around the hand-threshing work area from the cabin 9 side. The second camera 104 is located at the rear of the harvesting device 4 and is positioned in the space below the conveying cover that covers the upper part of the grain stalk conveying mechanism leading to the threshing device 4, and is fixed to the support frame of the conveying cover. The optical axis of this second camera is oriented in the front to back direction, and it images the area around the hand-threshing work area from the harvesting device 4 side, which is in front of the hand-threshing work area.

[0056] The work state estimation device 120 evaluates the state of manual threshing work mainly based on video data captured by the first camera 103 and the second camera 104. Markers are provided on the front wall 4A of the threshing machine 4 to identify the angle and position of the video captured by the cameras relative to the cameras. The markers are grayscale images of several pixels vertically and horizontally, and are recognized by the work state estimation device 120 by their arrangement. Multiple markers are attached, and the relationship between the real coordinate system and the camera coordinate system is evaluated based on how they appear in the video. For example, by attaching markers to the four vertices of a rectangle in a single plane on the front of the front wall 4A, the shape of this rectangle in the camera video can be used to recognize how the real coordinate system is depicted, and the position and size of objects appearing in the video can be evaluated.

[0057] By performing this coordinate system identification process on both the first camera 103 and the second camera 104, and considering their relative postures and positions, it becomes possible to more accurately evaluate the positions of objects captured by both cameras. In this way, the various functions of the work state estimation device 120, including the person detection unit 121, posture estimation unit 122, clothing determination unit 123, proximity determination unit 124, and motion determination unit 125, use the coordinate information obtained through the above coordinate system identification process, along with the images from the first camera 103 and the second camera 104, to perform various processing.

[0058] Furthermore, the various estimation and determination units in the work state estimation device 120 are pre-trained models created using machine learning. After being given training data to perform basic learning for determination, they have been fine-tuned to optimize them for the vehicle body and camera in question.

[0059] The person detection unit 121 of the work state estimation device 120 detects areas in which a person is visible in the images from the first camera 103 and the second camera 104. The way in which the person detection unit 121 outputs the determined information is arbitrary, but it outputs area coordinate information, including the size and position of the rectangular area surrounding the area in which the person is visible, along with a probability value that the area is a person.

[0060] The posture estimation unit 122 estimates the posture of a person based on the information of the person region extracted by the person detection unit 121. In posture estimation, the posture is estimated by fitting the person in the video to a predetermined human body shape model. That is, the positions corresponding to several key points such as the shoulders, elbows, and head are identified from the image, and a model of linear bone segments connecting these points is defined in the evaluation space of the real coordinate system to estimate where the worker is located and in what posture. Since the range captured by the first camera 103 and the second camera 104 is generally limited to the upper body, posture estimation is performed only on the upper body in order to reduce the computational load of video analysis.

[0061] The posture estimation unit 122 outputs meta-evaluation data about the person's posture, centering on the coordinate information of each key point and summarizing it.

[0062] The clothing determination unit 123 estimates and determines the state of the clothing worn by the person in the images from the first camera 103 and the second camera 104, respectively. In particular, it estimates whether or not gloves are being worn, which have a significant impact on the degree of danger in the work, and whether or not there is any dishevelment of clothing that could pose a risk of entanglement.

[0063] The clothing determination unit 123 determines whether or not gloves are being worn. Specifically, it calculates the skin tone of the worker by referring to the image pixel information of the area corresponding to the head or neck, based on the position information of the head or neck obtained by the posture estimation unit 122. Similarly, it calculates the skin tone of the area of ​​the wrist joint. Using the differences in these colors, as well as evaluation results from a function that evaluates the skin tone resemblance of a separately prepared color code (RGB value, etc.), it determines whether or not gloves are being worn on the hands. The clothing determination unit 123 also determines whether or not a towel is being worn around the neck. This is preferably determined from the skin tone of the neck, similar to the determination of whether or not gloves are being worn.

[0064] The clothing determination unit 123 performs the determination as described above, but since information on whether or not there are problems with the clothing alone is insufficient for risk assessment, it quantifies and outputs the degree of risk caused by the clothing.

[0065] The proximity determination unit 124 determines how close the worker's body is to the movable parts in the hand-threshing work unit. In hand-threshing work, the worker's arms pass over the feed chain 4B and are positioned on the hand-threshing work unit, and the forearms are hidden by bundles of straw, making it difficult to evaluate dangerous proximity to the movable parts from images. Therefore, the proximity determination unit 124 uses the output result of the aforementioned posture estimation unit 122 to evaluate dangerous proximity to the movable parts based on how close the worker's torso is to the danger zone. In other words, since the position and shape of the threshing device 4 and feed chain 4B are known, it is possible to determine in advance what area they occupy within the coordinate system of the imaging area. A danger zone is defined as an area within a certain distance from these components, and the degree of danger is evaluated based on the distance of the closest point of the torso (generally the bone segment connecting the key points of the neck and the key points of the waist). When defining the hazard zone, it is not necessary to maintain a uniform distance from the moving parts. The zone can be defined more broadly towards the rear of the machine, which is downstream of the feed chain 4B, or more broadly around exposed parts of the feed chain 4B and the opening of the threshing device 4. The zone can be specified as appropriate according to the actual risk. The proximity determination unit 124 outputs a numerical value representing the degree of danger due to proximity, and preferably further distinguishes between the degree of danger caused by the threshing unit (thresher) and the degree of danger caused by the feed chain 4B.

[0066] The motion determination unit 125 determines whether the worker's body has made a dangerous movement. Dangerous movements can be broadly divided into two types: the first is a movement that rapidly approaches a movable part, and the second is a movement that rapidly shifts downstream (towards the rear of the machine) in the conveying direction of the feed chain 4B. Both of these may indicate that the worker is being caught in the movable part, and even if the rapid approach to the movable part does not result in being caught, it is appropriate to evaluate it as a highly dangerous work action.

[0067] Therefore, the motion determination unit 125 monitors the movement of the torso using the output results of the attitude estimation unit 122, and particularly evaluates whether there is significant acceleration in the movement of the torso. In this way, it evaluates the degree of danger regarding the speed and acceleration of approaching movable parts and moving towards the rear of the aircraft, and outputs it as a numerical value.

[0068] With the configuration described above, the work state estimation device 120 comprehensively evaluates the work hazards based on the output results from the clothing determination unit 123, the proximity determination unit 124, and the movement determination unit 125, and outputs a countermeasure action command to the work vehicle control device 110 specifying an action to eliminate the hazard.

[0069] The corrective action commands are determined according to the degree of danger evaluated by the work state estimation device 120, and are in descending order of danger level, including stopping the engine E and releasing the thresher cover using the thresher cover release mechanism 135, stopping the feed chain 4B, slowing down the feed chain 4B, and issuing a warning using the warning output device 134. Multiple actions listed above can be combined. For example, when performing an action for a higher level of danger, actions prepared for a lower level of danger can be combined with it. Furthermore, the thresholds used to distinguish between corrective actions can be adjusted by the operator or mechanic.

[0070] In the example described above, the work state estimation device 120 comprehensively considers the output results from the clothing determination unit 123, the proximity determination unit 124, and the movement determination unit 125. However, it is also possible to evaluate the situation by taking the maximum value of the risk level output by these units, or by using a simple average or an average value weighted by any of them. Furthermore, it is possible to use only one of the determination units, in which case the computational load of the work state estimation device 120 can be reduced, and processing can be implemented using a device with low computational resources.

[0071] Furthermore, although the work state estimation device 120 evaluates the images from two cameras, the first camera 103 and the second camera 104, it may also use the images from a single camera or three or more cameras.

[0072] Furthermore, the posture estimation unit 122 estimates the posture of a person using images from the cameras (first camera 103 and second camera 104), but the posture may also be estimated using the cameras (first camera 103 and second camera 104) and the LIDAR device 105. In this case, it is preferable to install the LIDAR device 105 at a position lower than the height of the grain stalk transport of the feed chain 4B (the height of the grain stalk supply opening formed on the side of the threshing device 4) so ​​that distance measurement can be performed in the left direction of the machine. In other words, if the LIDAR device 105 is installed near the height of the grain stalk transport, the transported grain stalks may obstruct the distance measurement, and there is a risk that distance measurement data necessary for estimating the posture of a person cannot be obtained. It is also possible to attach the LIDAR device 105 to the harvesting device 3, but it is necessary to consider that its relative position to the threshing device 4 will change due to its lifting and lowering operation.

[0073] As described above, by installing the LIDAR device 105, the first camera 103 and the second camera 104 will mainly acquire person information above the height of the grain stalks, and the LIDAR device 105 will mainly acquire person information below the height of the grain stalks. As previously mentioned, the posture estimation unit 122 is interested in the posture of the torso, and estimates the posture of the torso by determining the position of the neck through image analysis of the cameras (first camera 103 and second camera 104) and determining the position of the waist based on the distance measurement results of the LIDAR device 105.

[0074] With this configuration, above the height of the grain stalks being transported, the camera can estimate the position of key points that are difficult to estimate using electromagnetic wave ranging methods due to noise from the transported grain stalks and straw, while also acquiring other risk assessment information such as clothing. Below the height of the grain stalks being transported, it is possible to accurately acquire information on the posture of people in the blind spots of the camera, and to accurately measure the relative distance to the threshing device 4.

[0075] Furthermore, while the LIDAR device 105 is used for attitude determination by the attitude estimation unit 122, the work state estimation device 120 can also output a response action command without going through the proximity determination unit 124 or the motion determination unit 125 if it detects an object approaching at close range or moving at high speed, separate from the processing by the attitude estimation unit 122. In this case, the delay due to the information processing load can be reduced, and a response action command can be issued quickly, thereby improving worker safety. [Explanation of Symbols]

[0076] 4. Threshing machine 4B Feed Chain 103 Camera 1 (camera) 104 Second camera (camera) 105 LIDAR device (ranging device) 120 Working state estimation device 122 Posture estimation section

Claims

1. A threshing device (4) for threshing grain stalks, A feed chain (4B) that supplies grain stalks to the threshing device (4), Cameras (103, 104) and a distance measuring device (105) for monitoring the operator's manual handling work, The system includes a work state estimation device (120) that evaluates the degree of danger to the worker's work from the video captured by the cameras (103, 104) and distance information obtained by the distance measuring device (105), The work state estimation device (120) has a posture estimation unit (122) that estimates the posture of the worker's body from the positional information of specific parts of the worker's body identified from the video and the distance information from the distance measuring device (105), and also evaluates the degree of risk of the posture. A combine harvester characterized by the following features.

2. The cameras (103, 104) are positioned above the height of the grain stalks being transported by the feed chain (4B). The combine harvester according to claim 1, wherein the distance measuring device (105) is positioned below the height of the grain stalks being transported by the feed chain (4B).

3. The combine harvester according to claim 1 or 2, wherein the work state estimation device (120) is capable of evaluating the degree of risk of work using the estimation results of the posture estimation unit (122) and evaluating the degree of risk of work without using the estimation results of the posture estimation unit (122).

Images