JPH082730Y2 - Harvester automatic steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an automatic steering apparatus for a harvester that automatically steers the harvester based on information obtained by imaging the state of a work site.

[Prior Art] A conventional working machine equipped with an automatic steering device is capable of automatically steering a machine in order to mow threshing rice rows planted in a field in order from the outer periphery near the ridge of the field. There is a harvester.

An example of this is the invention disclosed in JP-A-62-70916. This is a Hough that images a work site including an unworked site and an already-worked site by an image pickup means mounted on a body of a harvester, binarizes an image obtained by this, and tabulates binarized image information in advance. By performing Hough transform processing using the values (ρ, θ), the boundary between the already-worked site and the unworked site is determined, and the harvester is automatically steered along this boundary line. .

In such a harvesting machine, a method of discriminating a boundary between a work place and a non-work place of a work place by detecting a tip of a grain culm and automatically steering is used.

[Problems to be solved by the device]

However, in the image obtained by the image pickup apparatus, the size of the object to be imaged differs depending on the difference in distance from the airframe, which is large in the vicinity of the airframe and becomes smaller as the distance from the airframe increases.

That is, when the boundary area including the unworked site and the already-worked site is imaged by the imaging means mounted on the aircraft, the image near the aircraft is located in the lower part of the normal image, and as the image goes up, the image of the point farther from the aircraft is displayed. The images are located, and these images have a large size of the object to be imaged below the image as described above, and become smaller as going upward. In other words, the area of the imaged object captured in the unit pixel is small below the image,
It becomes wider toward the top of the image.

In other words, the image information density, which is the area of the imaging target imaged in the unit pixel, is low in the lower part of the image and increases in the upper part, and in the same image, the image information density varies depending on the location.

Looking at this in the row of grain culms, it is coarse in the lower part of the image and dense in the upper part. Therefore, for images with different information densities, for example, when sampling the pixels to apply Hough transform, the sampling data There will be a bias in In the Hough transform, for each point sampled from the image (whose coordinates are (x, y)), this is converted to the ρ-θ plane by the conversion formula of ρ = xcosθ + ysinθ,
By mapping on a so-called Hough curve on a so-called parameter plane and obtaining the equation of the straight line to be extracted from the ρ and θ values of the intersections of the concentrated curves, it is possible to extract an accurate straight line equation if there is a deviation in the sampling data. It becomes difficult.

The present invention has been made in view of such circumstances, and an object thereof is to provide an automatic steering device for a harvester that performs highly accurate linear approximation by making the image information density on the same image uniform. To do.

[Means for solving the problem]

An automatic steering device for a harvester according to the present invention is a harvester that images a row of grain culms, uses image information obtained thereby as steering information, and automatically steers in accordance with the row of grain culms. In the automatic steering apparatus of, the image is enlarged by increasing the image information density in a region where the image information density is high, and reducing the image in the region where the image information density is low in the image by increasing the image information density. It is characterized by comprising means for making the image information density uniform.

[Action]

In the present invention, when the image information density is high, the image is enlarged so that the image information density is low, and when the image information density is low, the image is reduced so that the image information density is high. The information density can be made uniform.

〔Example〕

Hereinafter, the present invention will be specifically described with reference to the drawings showing an embodiment thereof.

FIG. 1 is a side view of a general-purpose combine which is a harvester according to the present invention, and FIG. 2 is a plan view thereof.

In the figure, 1 is a machine body mounted on the upper side of a pair of left and right traveling crawlers 2, 2 (only one side is shown), and a threshing section 3 is installed on the upper left side of the machine body 1 over the entire length in the front-rear direction,
A driver's seat 10, a grain culm tank 11 and an engine (not shown) are installed on the right side of the upper part, and a reaping unit 4 is mounted on the front side of the machine body 1 so as to be movable up and down.

The traveling crawlers 2 and 2 are driven simultaneously or separately on the left and right by the driving force of the engine transmitted via a main clutch (not shown), a hydrostatic continuously variable transmission, and side clutches on each of the left and right rows. Forward, reverse or turn.

As the machine body 1 advances, grain is introduced into the mowing section 4 from between a pair of left and right dividers 41, 41 provided in the front part of the mowing section 4, and the grain extends in the left-right direction in the axial direction above the mowing section 4. While being pulled backward by the rotation of the take-up reel 42 with the tine bar 43 that is rotatably supported, the cutting blade 43 is repeatedly arranged in the lower part of the mowing section 4 and is repeatedly moved in the left-right direction. Further, the take-up reel 42 has a shaft end rotatably supported and a platform 45 arranged on the rear side of the cutting blade 43.
It is supported so as to be movable in the front-back and up-down directions with respect to both side walls.

Inside the dividers 41, 41, a grain culm detection sensor 9 using an ultrasonic sensor having a pair of transmitter and receiver,
9 is attached. The grain culm detection sensors 9 and 9 detect the ultrasonic waves transmitted toward the grain culm C closest to the divider 41 among the cultivated grain culms located within the left and right width of the platform 45 in the cutting unit 4. The reflected sound is received by the receiver, and the detection distance (LK) from the side of the divider 41 to the grain culm, which is located in the lateral direction approximately at right angles to the traveling direction of the aircraft 1, is detected depending on the time from transmission to reception. Moreover, the presence or absence of grain culms is determined by utilizing the fact that the ultrasonic waves are blocked by the grain culms.

On the other hand, on the upper side of the platform 45, a lateral conveyance auger 44 formed in a columnar shape and forming a spiral conveyance plate 44a on its peripheral surface is axially supported with its axial direction being the left-right direction,
The grain cut by the cutting blade 43 is transferred to the platform 45 according to the rotation of the lateral transport auger 44 by the action of the transport plate 44a.
It is conveyed laterally above, and the rear part of the reaper 4 and the threshing part 3
At the front end opening of the feeder house 5 that communicates with the front part of the chain conveyor 50.
And the bottom plate of the feeder house 5, the sheet is conveyed upward and rearward, and introduced into the handling chamber 30 of the threshing unit 3 through the rear end opening of the feeder house 5.

In the handling chamber 30, a handling cylinder (not shown) formed by spirally forming a double-pitch screw and a large number of handling teeth on the circumferential surface of the cylinder is axially supported with the axial direction as the front-rear direction,
The grain introduced into the handling chamber 30 is transported rearward by the action of the screw according to the rotation of the screw handling barrel, and is threshed by the action of the handling tooth. After threshing processing, the grated food passes through the net 33 that is stretched on the lower side of the hoisting drum, and falls onto the rocking and sorting device 32 arranged at the lower part of the threshing section 3, and the device. Specific gravity selection is performed by a synergistic effect of the swinging of 32 and the selection wind that is blown by the Karato device 34 installed on the front side of the lowermost part of the threshing unit 3 and is blown as shown by the hollow arrow in FIG. . That is, the refined grains having a relatively large specific gravity in the grated food fall onto No. 1 gutter (not shown) provided in the lower portion on the upstream side of the sorting wind, and are conveyed to a frying cylinder connected to the gutter. The fried grain cylinder is conveyed upward and stored in the grain tank 11. In addition, the second ones, such as cuttings and buds,
Not shown 2 excreted on the downstream side of the sorting wind from the 1st gutter
It drops on the gutter and is transported to the right, and is transported toward the upper front in the No. 2 reduction cylinder 35 that is connected to the right end of the gutter.
Is re-introduced to the foremost part and reprocessed. Further, the third object such as straw and dust contained in the grated food is blown backward by the sorting wind and discharged at the last part of the handling cylinder together with the last part of the threshing part 3. It is discharged onto the field through the No. 3 opening 36 that opens downward.

Further, behind the driver's seat 10, there are disposed exhaust pipes 37, 37 communicating with the grain tank 11, and the exhaust pipes 37, 37 are provided.
Discharges the grains in the grain tank 11 to the outside.

When detecting symmetry, the image pickup device 6 including a color video camera for obtaining color information is an area sensor having an image pickup screen having a two-dimensional plane having a vertical and horizontal spread, and is an optical sensor of the image pickup screen sensed by the image pickup element. Information can be output as an electric signal, and it is attached to the right end portion of the body 1 of the pillar above the front of the driver's seat 10 with the center of the lens portion facing forward and downward with respect to the traveling direction of the body 1. There is.

The image pickup device 6 outputs an image picked up in the field of view to an image processing unit 60 described later.

Now, FIG. 3 is a block diagram of a control system, and FIG. 4 is a block diagram showing a configuration of an image processing unit.

In the figure, reference numeral 100 denotes a steering control section using a microprocessor, and an output of the image processing section 60 is given to an input port a ₁ of the steering control section 100. The image processing unit 60 is a NTSC decoder that uses a microprocessor and separates the image pickup device 6 and the NTSC video camera input signal into red, green and blue color signals R, G and B for each pixel of the image processing unit. A camera input signal conversion unit 601, an area extraction unit 602 that extracts an image area having a shape in which the range becomes narrower from the lower part of the image toward the upper part of the image,
The upper part of the image area extracted by the area extracting unit 602 is enlarged by a predetermined amount, and the information density uniformizing unit 603 that uniformizes the information density of the entire image area, using a predetermined conditional expression that detects the yellow component of the tip, A binarization calculation unit 604 that binarizes image information in which the information density is uniformed depending on the amount of yellow component, and pixel extraction that extracts pixels having a predetermined inter-pixel distance from the binarized pixels. The unit 605 and the Hough transform unit 606 that performs linear approximation by the extracted pixels are connected in this order.

The information density equalization unit 603, the binarization calculation unit 604, the pixel extraction unit 605, and the Hough conversion unit 606 perform the calculation by the microprocessor, and the output signal of the Hough conversion unit 606 is the steering control unit 100. The input results are given to the input port a ₁ and the detection results of the grain culm detection sensors 9 9 are given to the input ports a ₂ and a ₃ , respectively.

An automatic steering switch 102, which is arranged at a position that can be manually operated by an operator and is turned on when performing automatic steering, is connected to the input port a ₄ , and the automatic steering switch 102 is turned on. In this case, the input port a ₄ goes high.

On the other hand, the output port b ₁ of the steering control unit 100 is
It is connected to an electromagnetic solenoid of a hydraulic switching valve (not shown) that operates the right side clutch 21 that transmits the power from the engine to the right side of the crawler 2 in accordance with the output signal of 00, and similarly to this, the output port b ₂ Is the left side clutch 22
Is connected to an electromagnetic solenoid for operating the right side clutch 21 and the left side clutch 22 based on the output signal of the steering control unit 100 to control the steering of the machine body 1.

The output port b ₃ is connected to an electromagnetic solenoid (not shown) that operates the reaper drive clutch 40 that transmits power from the engine to the reaper 4, and the input port a ₄
Alternatively, when a ₅ is at a high level, that is, when a grain culm detection sensor detects a grain culm, the reaper section drive clutch 40 is engaged to drive the reaper section 4. .

Steering control unit 100, image processing unit 60, grain culm detection sensor 9,9,
Each of the automatic steering switches 102 is connected to a power source via a key switch 101 for starting an engine, and can perform its operation only when the switch 101 is turned on.

Next, the operation content of the steering control unit 100 configured as above will be described.

FIG. 5 is a flowchart of the entire control relating to the automatic steering of the image processing unit 60, and FIGS. 6A to 6C are the image processing unit 60.
FIG. 3 is a schematic diagram showing a method for equalizing the information density of an image in FIG. In FIG. 6, (a) is a plan view of a field surface having a row A of grain shoots imaged by the imaging device 6, and (b) is an image area extracted by the area extraction unit 602 when the field surface is imaged. FIG. 3C is a schematic diagram showing an image in which the information density of the image area extracted by the area extracting unit 602 is uniformized by the information density uniformizing unit 603.

First, in step 1, when the image capturing device 6 captures an image of the row A of grain culms as shown in FIG. 6 (a),
The image processing unit 60 takes in a camera input signal which is the image information of the image pickup device 6 at every setting timing, and separates it into each color signal R, G, B of a red signal, a green signal and a blue signal by a camera input signal conversion unit 601. To do.

In step 2, as shown in FIG. 6 (b), the extraction area of the image data in the distance is narrowed in the image extracted from the image input from the camera input signal conversion section 601 in the area extraction unit 602, and the image data in the vicinity is extracted. The extracted image area B is extracted so that the extraction area is widened. In this case, the sampling density for extracting the data is set such that the upper part of the imaged data in the distance, that is, the upper part of the image is made higher, and the sampling density is gradually lowered toward the lower part of the imaged data in the vicinity, namely the lower part of the image.

Next, in step 3, as shown in FIG. 6 (c), the information density equalizing unit 603 makes the sampling density, which is the information density of the image area extracted by the area extracting unit 602, uniform throughout. Magnify the top of the image. The setting of the sampling density in the area extracting unit 602 is performed by enlarging the image in the information density uniformizing unit 603,
As a result of making the sampling densities of the images uniform, the sampling intervals for the field surface when the field surface is viewed in plan are set to be equal in the entire image.

In step 4, the image information whose information density is uniformized by the information density uniforming unit 603 is sampled for each predetermined pixel by the binarizing arithmetic unit 604, and the color signals R, G, B of the sampled data are sampled. Binarization is performed using a predetermined conditional expression that detects the yellow component of the tip.

In step 5, the pixel extraction unit 605 extracts the pixels that satisfy the conditional expression and are determined to be the tips of the pixels in the predetermined range in step 4. And step 6
At H.sub.F, these extracted pixels are Hough transformed at Hough transform unit 606 to linearly approximate the row of tips.

In step 7, the Hough transform unit 606 outputs the data linearly approximated by the Hough transform to the steering control unit 100 at every predetermined timing.

The steering control unit 100 automatically steers the machine body 1 based on the linear approximation data provided by the image processing unit 60, following the row of the tips of the grain stems.

In this embodiment, the information density of the image information is made uniform by enlarging the image area captured in the distant place, but not limited to this, the information density of the image information is reduced by reducing the image area captured in the vicinity. May be made uniform.

[Effect of device]

As described above in detail, in the automatic steering apparatus for a harvester according to the present invention, the present invention has excellent effects such as high accuracy of linear approximation by making the image information density on the same image uniform.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a side view of a general-purpose combine equipped with an automatic steering device for a harvester according to the present invention, FIG. 2 is its plan view, and FIG. FIG. 4 is a block diagram of the image processing unit, FIG. 4 is a block diagram of the steering control unit, FIG. 5 is a flow chart of control relating to automatic steering of the image processing unit, and FIG. 6 is a uniform image information density in the image processing unit. It is a schematic diagram which shows the method. 1 ... Airframe, 3 ... Threshing unit, 4 ... Mowing unit 60 ... Image processing unit, 602 ... Region extraction unit 603 ... Information density equalization unit

Claims (1)

[Scope of utility model registration request] 1. An automatic steering device of a harvester, which images a row of grain culms, uses image information obtained thereby as steering information, and automatically steers in accordance with the row of grain culms. Means for equalizing the image information density in the image by enlarging the image so that the image information density is low in the high information density area and reducing the image so that the image information density is high in the low image information density area An automatic steering device for a harvester, comprising: