JP5773607B2 - Paddy field weeding robot - Google Patents

Description

  The present invention relates to a paddy weeding robot that weeds grass generated in a paddy field, and more particularly to a paddy weeding robot that can perform weeding while traveling autonomously in the paddy field.

  Currently, paddy field weeding is mainly carried out by chemical control methods using herbicides because of the labor saving and high herbicidal effect. However, in recent years, there has been a demand for adopting paddy rice cultivation that does not use herbicides, for reasons such as diversification of consumer needs, orientation of agricultural chemicals, and reduction of environmental burden. Known herbicidal methods that do not use pesticides include mechanical weeding typified by walking weeders, physical weeding with paper mulch, and biological weeding methods typified by Aigamo farming.

  There are two types of walking type weeders: hand-held type and power type. In addition, there are riding-type weeders that do not require workers to walk. Since the hand-held type is a walking operation, it is a harsh labor in paddy fields under hot weather. In addition, although the riding type can reduce labor, it is much more expensive than the hand-held type and may not be easily used. Biological weeding is a method of weeding and controlling pests using Aigamo duck that has been released to paddy fields, but its herbicidal and pest control effects are not always stable, and it has become widespread due to the labor and cost of breeding. It has not been done.

  In view of this, an unmanned weeding robot has been proposed that does not require human labor and labor, and that enables economical weeding. For example, a field traveling device (see Patent Document 1) that drives a pair of endless belts to rotate with a motor and travels a pre-programmed traveling path to press grass against soil and suppress the propagation of grass and the like (see Patent Document 1). A weeding robot that attaches to the front and back of the body equipped to remove weeds floating in the paddy field and stirs the surface soil of the paddy field to make it cloudy, thereby blocking sunlight and preventing germination (patented) Reference 2), front, rear, left and right wheels with stirring claws are driven by an engine or a motor and are driven to rotate at a constant speed and a different speed by a gear, and the running is controlled by a microcomputer while detecting a rice plant with a sensor. There is an agricultural management robot (see Patent Document 3).

  In addition to detecting rice stock with a contact or non-contact sensor, the robot is equipped with a camera, and the color components of the image taken with this camera are extracted to detect the rice row. A method of detecting (see Non-Patent Document 1), a method of extracting a row of rice from an image of paddy fields using the spectral reflection characteristics of rice (see Non-Patent Document 2), and the like have been proposed.

JP-A-2005-198604 JP 2007-129910 A JP 2005-65664 A

"Autonomous vehicle for paddy field weeding by image feedback control" Journal of Agricultural Machinery Society Vol. 66, No. 2 (2004) "Development of small weeding robot for paddy field (Aigamo robot)" Gifu Prefectural Information Technology Research Institute Research Report No. 10 (2008)

  In the conventional field running apparatus and each robot described above, the paddy rice is easily shaken or tilted by the influence of the natural environment such as wind. Since it is difficult to travel stably, full automation of weeding is hindered, and many problems remain in practical use. In addition, stable running is possible only in the streak (which means the wider rice pitch), and it is difficult to weed the inter-strain (which means the narrower rice pitch). At present, the level of performance is such that it is impossible to travel on the road. Furthermore, the detection of paddy rice using image processing as shown in Non-Patent Documents 1 and 2 is likely to be affected by the inclination of the vehicle body, and the rice row may not be detected accurately. Further, since the time required for the calculation process becomes long, there is a problem that the control device becomes expensive when it is attempted to obtain a processing speed in accordance with practical use.

  Accordingly, an object of the present invention is to provide a weeding robot that can freely move between streaks and strains and can obtain a stable weeding effect.

In order to achieve the above object, the following paddy field weeding robot is provided.
[1] A main body having a space through which rice plants can pass in a central portion, a pair or a plurality of wheels provided at a lower portion of the main body, a plurality of driving units for driving each of the wheels, and the main body A pair or a plurality of pairs of floats provided in the lower part of the main body, detection means provided in the front part of the main body for detecting the rice stock, and the drive unit so that the rice stock passes through the center of the space. A paddy weeding robot, comprising: a control device for controlling rotation of the wheel via a wheel.

[2] The main body includes a direction sensor that detects a direction in which the main body is traveling, and the control device measures the number of rice stocks that the main body passes to grasp the shape of the paddy field being weeded. The paddy weeding robot according to [1], wherein an unweeded area is determined on the basis of position information of the direction sensor.

[3] The main body is provided with a pair of paddy detectors for detecting paddy paddy at the front part thereof, and the control device drives the wheel so that the wheels are reversed when the paddle detector detects paddles. The paddy weeding robot according to [1], wherein the paddy field weeding robot is controlled.

[4] The paddy weeding robot according to [1], wherein each of the pair or plural pairs of wheels has a disk shape, and a plurality of fins are fixedly installed radially on one surface thereof. .

[5] Each of the pair or the plurality of pairs of wheels has a disk shape, a plurality of fins provided radially on one side thereof, and one end of the plurality of fins provided on the one side. A plurality of fulcrums pivotally supported on one side, a plurality of first stoppers provided on the one side and locking the other ends of the plurality of fins on the outer peripheral side of the wheel according to the rotational state of the wheel, and the one side A plurality of second stoppers which are provided on the inner peripheral side of the wheel according to a rotation state of the wheel, and wherein the other ends of the plurality of fins are engaged with each other according to a rotation state of the wheel. The paddy weeding robot described.

[6] The paddy field according to [1], wherein the drive unit includes a motor and a speed change mechanism that transmits a rotational force of the motor to the wheel, and is disposed at a lower portion of the main body. Weeding robot.

[7] The pair or the plurality of pairs of floats are disposed before and after the pair or the plurality of pairs of wheels, and the main body includes an elevating drive mechanism that individually raises and lowers each of the floats, and the control device includes: The paddy weeding robot according to [1], wherein the lifting drive mechanism is controlled so that the posture of the main body becomes a normal state based on detection information with respect to a change in posture of the main body from a normal state.

[8] The detection means is configured to be in contact with the rice stock, provided below the front portion of the main body, and one end of which rotates according to a contact state with the rice stock, and the pair of contacts Rotation angle detecting means for outputting an electric signal corresponding to each rotation state of the contact, and the control device includes two electric signals corresponding to the rotation angle of the pair of contacts by the rotation angle detecting means. The paddy weeding robot according to [1], wherein the driving unit is controlled so that the rice plant is positioned at the central portion of the main body based on the difference value.

[9] Separately from the float provided at the lower part of the main body, each of the pair of second floats provided on both sides of the front part of the main body so as to be movable up and down, and the second float is provided. The paddy weeding robot according to [1], further comprising: a plurality of capacitance sensors that detect the rice plant by a change in capacitance.

[10] The plurality of capacitance sensors are arranged adjacent to each other in a state of being electrically insulated from each other, and at least a pair of first contactors disposed on the second float so as to be able to contact the rice plant. And in contact with the rice plant and installed in the vicinity of the first contact of the second float in a state insulated from the first contact and other components. A second contactor, and a capacitance detection value for the rice strain with a difference between a capacitance change amount by the first contactor and a capacitance change amount by the second contactor, and The paddy field weeding robot according to [9], wherein:

  According to the paddy field weeding robot of the present invention, it is possible to freely move between streaks and strains and to perform stable weeding efficiently.

It is a perspective view which shows 1st Embodiment of the paddy field weeding robot which concerns on this invention. It is a top view of the paddy field weeding robot shown in FIG. It is a front view of the paddy field weeding robot shown in FIG. It is a left view of the paddy field weeding robot shown in FIG. It is a block diagram which shows the structure of a control system. It is a figure which shows the structure of the rice plant buffer set to the memory of the control apparatus of FIG. It is a figure explaining the driving | running | working locus | trajectory at the time of a paddy field weeding robot drive | working a paddy field. It is a figure which shows the mode of rotation of the wheel of the paddy field weeding robot which concerns on 1st Embodiment in a paddy field. It is a figure which shows the relationship between the sensor lever of the paddy field weeding robot which concerns on this invention, and a rice plant. It is a flowchart which shows the process of 1st Embodiment of the paddy field weeding robot which concerns on this invention. It is a flowchart which shows the process of a hull detection of the paddy field weeding robot which concerns on this invention. It is a front view which shows the structure of the wheel in 2nd Embodiment of the paddy field weeding robot which concerns on this invention. It is a perspective view which shows 3rd Embodiment of the paddy field weeding robot which concerns on this invention. It is a top view of the paddy field weeding robot shown in FIG. It is a front view of the paddy field weeding robot shown in FIG. It is a left view of the paddy field weeding robot shown in FIG. It is a perspective view of the paddy field weeding robot shown in FIG. It is a block diagram which shows the structure of the control apparatus in 3rd Embodiment. It is explanatory drawing which shows the driving | running locus | trajectory of the paddy field weeding robot in 3rd Embodiment. It is a figure explaining the contact condition of the contactor and rice plant in the paddy field weeding robot of 3rd Embodiment. It is a flowchart which shows the process of 3rd Embodiment of the paddy field weeding robot which concerns on this invention.

[First Embodiment]
1 is a perspective view of a first embodiment of a paddy weeding robot according to the present invention, FIG. 2 is a plan view, FIG. 3 is a front view, and FIG. 4 is a side view. As shown in FIG. 1, the paddy weeding robot 1 has a space 10 a (see FIG. 3) through which rice plants can pass in the central portion, and is provided on the main frame 10 as a main body and on the left and right of the lower portion of the main frame 10. A pair of drive units 11A and 11B, a drive control unit 12 for controlling the drive units 11A and 11B, a calculation unit 13 for controlling the drive control unit 12 according to a program, and a lifting motor provided on the upper part of the main frame 10 14A, 14B.

  The drive units 11 </ b> A and 11 </ b> B run the paddy weeding robot 1 and are provided on the left and right sides of the main frame 10. The configuration of the drive unit 11A will be described. A drive motor (drive source) 16 disposed as shown in FIG. 4 and a gear 17 (FIG. 2 and FIG. 2) as a speed change mechanism to which the rotation of the drive motor 16 is transmitted. 4), a wheel 19A that is coaxially attached to the gear 17 and has a plurality of radial fins 18A (see FIGS. 1 to 4) attached to one surface (outer surface), and front and rear of the wheel 19A. The first floats 20A and 20B are disposed and fixedly installed at the lower portion of the main frame 10. Similarly, the drive unit 11B includes a drive motor (not shown), a gear (not shown), a wheel 19B having a plurality of fins 18B attached to the side surfaces, and first floats 20C and 20D. The drive units 11A and 11B are configured to operate independently. As a result, the wheels 19A and 19B can be individually rotated. As a result, the paddy weeding robot 1 can be turned.

  The elevating motors 14A and 14B are drive sources for raising and lowering the first floats 20A to 20D. The elevating motors 14A and 14B are coupled to the first floats 20A to 20D via two screws 21 as shown in FIG. The drive units 11A and 11B, the drive control unit 12, and the calculation unit 13 are supplied with power from a power supply unit (including a battery and a stabilized power supply circuit) 22 shown in FIG.

  As shown in FIG. 4, since the drive motor 16 is installed at substantially the same height as the axis of the wheels 19A and 19B, the center of gravity of the paddy weeding robot 1 is lowered, thereby stabilizing the paddy weeding robot 1. Driving is possible. The drive motor 16 is individually provided in the drive units 11A and 11B. However, the drive units 11A and 11B are each provided with a speed change mechanism and a single drive source to drive the drive units 11A and 11B. You may do it. In this case, an internal combustion engine can be used as the drive source in addition to the motor.

  The first floats 20A to 20D are for generating a predetermined buoyancy in the paddy weeding robot 1 so that the paddy weeding robot 1 set in the paddy field does not sink. In the case of the present embodiment, about 60% of the buoyancy of about 5 kg) may be generated. In the case of the present embodiment, the buoyancy is 3 kg. When the buoyancy of the first floats 20A to 20D is equal to or greater than the weight of the paddy weeding robot 1, the wheels 19A and 19B run idle due to the wheels 19A and 19B moving away from the ground, and the paddy weeding robot 1 cannot advance. There is. Therefore, the buoyancy of the first floats 20 </ b> A to 20 </ b> D needs to be less than the weight of the paddy weeding robot 1.

Further, as shown in FIGS. 2 and 3, the paddy weeding robot 1 includes sensor levers 23A and 23B as contactors mounted horizontally on both sides below the main frame 10 so as to be freely rotatable.
Potentiometers (or variable resistors) 24A and 24B as rotation angle detecting means that are attached to the rotation shafts 230A and 230B of the sensor levers 23A and 23B and change the resistance value according to the rotation thereof, and the presence or absence of wrinkles are detected. Bumper switches (see FIG. 3) 25A and 25B serving as a soot detector to detect, an orientation sensor 26 (see FIG. 2) for detecting the traveling direction of the paddy weeding robot 1 by geomagnetism, and the posture of the paddy weeding robot 1 are detected. And a gyro sensor 27. The direction sensor 26 and the gyro sensor 27 are installed on the upper part of the main frame 10, and these are protected by a case 28.

  FIG. 5 is a block diagram illustrating a configuration of a control device including the drive control unit 12 and the calculation unit 13. The control device 30 includes the drive control unit 12 including a driver circuit, the arithmetic unit 13 using a CPU, a program for autonomously running the paddy weeding robot 1, data necessary for executing the program, The memory 31 stores the data generated during the execution of the program and has an area for the rice buffer 32, and the power supply unit 22. The memory 31 is a semiconductor memory, for example, and is provided so as to be built in or detachable.

  Potentiometers 24A and 24B, bumper switches 25A and 25B, a direction sensor 26 and a gyro sensor 27 are connected to the calculation unit 13, and lifting motors 14A and 14B and a driving motor 16 are connected to the output side. Yes. In FIG. 5, the potentiometers 24 </ b> A and 24 </ b> B, the bumper switches 25 </ b> A and 25 </ b> B, the azimuth sensor 26, and the gyro sensor 27 are not shown in the figure such as a digitization circuit that is required for input to the calculation unit 13.

  FIG. 6 is a diagram showing the configuration of the rice stock buffer set in the memory 31. The rice buffer 32 is represented by MAP [m] [n] when the count values are m and n. In FIG. 6, if the count values m and n are directed to MAP [0] [n], data indicating the north direction is displayed. If the count values m and n are directed to MAP [m] [n], data indicating the south direction is displayed. The data indicates the west direction when heading, and the data indicates the east direction when heading MAP [m] [0].

  In order for the paddy weeding robot 1 to travel all over the paddy field, it is necessary to travel the headland as well. Accordingly, it is desirable that the paddy weeding robot 1 has a total length of 320 mm, a total width of 340 mm, and the width of one of the left and right bodies is about 130 mm. By satisfying such conditions, the paddy weeding robot 1 can move from the streak to the stock.

(Operation of paddy weeding robot)
Next, the operation of the paddy weeding robot 1 will be described with reference to FIGS. FIG. 7 is a diagram illustrating an example of a traveling locus of the paddy field weeding robot 1. First, the operator transports the paddy weeding robot 1 to the paddy field where weeding is desired, and then positions (sets) the paddy weeding robot 1 between the strips. Next, a power switch (not shown) is turned on. When the power is turned on, the drive control unit 12 and the calculation unit 13 of the control device 30 start to operate, whereby the drive motor 16 shown in FIG. 4 rotates, and the driving force is transmitted through the gear wheel 17 to the wheels 19A and 19B. Is transmitted to the paddy field weeding robot 1. The paddy weeding robot 1 performs weeding while traveling. As shown in FIG. 7, the paddy weeding robot 1 performs weeding by moving the paddy weeding robot 1 from the position A → the position B → the position C between the lines of the paddy field comprising the rice stock 41. Is.

  (A), (b), (c) of FIG. 8 is a figure which shows the mode of rotation of the wheel 19A in a paddy field. Here, although the wheel 19A is illustrated, the same applies to the wheel 19B. In the figure, the upper broken line indicates the water surface (WL), and the lower uneven line indicates the soil surface (GL). The plurality of fins 18A provided radially on the wheel 19A are partially buried in water so as to be pierced into the soil as the wheel 19A rotates as shown in FIG. When the rotation of the wheel 19A proceeds, as shown in FIG. 8 (b), several fins located at the lower part of the plurality of fins 18A rotate so as to catch a part of the soil. Further, when the rotation of the wheel 19A proceeds, one or more of the fins 18A peel off part of the soil together with the weeds 40 as shown in FIG. The weeds 40 extracted by the fins 18A float in the water and eventually die. Further, since the paddy field weeding robot 1 travels, the paddy water becomes cloudy, so that the photosynthesis of weeds germinated under the surface of the water is inhibited and its growth is suppressed.

  In order to smoothly advance the weeding work by the paddy field weeding robot 1, it is necessary for the paddy field weeding robot 1 to continue traveling along the rice row as shown in FIG. Therefore, the paddy weeding robot 1 detects a row of rice, and controls the control device 30 based on the detection result. This will be described below.

  FIG. 9 is a diagram showing the relationship between the sensor lever of the paddy weeding robot and the rice stock. Here, it is assumed that the paddy weeding robot 1 is traveling from the lower side to the upper side of the paper shown in FIGS. 7 and 9. As shown in FIG. 9A, when the rice plant 41 is in the center of the paddy weeding robot 1, as the paddy weeding robot 1 proceeds thereafter, the sensor levers 23 </ b> A and 23 </ b> B are brought into contact with the rice plant 41. The left and right rotation angles have substantially the same value as shown in FIG. In addition, as shown in FIG. 9C, when the rice plant 41 is on the left side in the traveling direction with respect to the center of the paddy weeding robot 1 (intermediate position between the sensor levers 23A and 23B), The rotation angle of the sensor lever 23A is large (that is, the output value of the potentiometer 24A is large. Further, as shown in FIG. 9 (d), the rice stock 41 is located on the right side in the traveling direction with respect to the center of the paddy weeding robot 1. In this case, the rotation angle of the sensor lever 23B is larger than the sensor lever 23A.

  In order for the paddy weeding robot 1 to travel as shown in FIG. 7 while positioning the rice plant 41 at the center, the rotation angles of the sensor lever 23A and the sensor lever 23B are compared, and the sensor lever 23A is compared with the sensor lever 23B. If larger, the calculation unit 13 rotates the wheel 19B faster than the wheel 19A, and if the rotation of the sensor lever 23B is larger than the sensor lever 23A, the calculation unit 13 rotates the wheel 19A faster than the wheel 19B. Make an exact copy of The rotation states of the sensor levers 23A and 23B are transmitted to the potentiometers 24A and 24B, and the voltage signals corresponding to the rotations of these rotary shafts are digitized and then taken into the arithmetic unit 13 shown in FIG.

  Details of the control by the calculation unit 13 will be described with reference to a flowchart shown in FIG. First, the calculating part 13 acquires the rotation angle of sensor lever 23A, 23B, ie, the output value of potentiometer 24A, 24B (S100). Next, the calculation unit 13 compares the output value of the potentiometer 24A with the output value of the potentiometer 24B, and when there is no difference between the two rotation angles of the sensor levers 23A and 23B (right rotation angle = left rotation angle) (S101: Yes), that is, when the sensor levers 23A and 23B are both in contact with the rice plant 41 at the center of the paddy weeding robot 1 as shown in FIG. (S105). The calculation unit 13 compares the target azimuth with the current azimuth (S106). If there is no difference between the two (S106: Yes), the calculation unit 13 controls the drive units 11A and 11B so that the paddy weeding robot 1 travels straight. (S110).

  Further, when the current direction is larger than the target direction in step S106 (S107: Yes), that is, as shown in FIG. 9D, the rice stock 41 is on the right side of the center of the paddy weeding robot 1 (with respect to the traveling direction). ), The driving units 11A and 11B are controlled by the calculation unit 13, and the paddy weeding robot 1 is turned to the right (S108). Further, when the current direction is smaller than the target direction (S107: No), that is, when the rice stock 41 is on the left side (relative to the traveling direction) from the center of the paddy weeding robot 1 as shown in FIG. Then, the driving units 11A and 11B are controlled by the calculation unit 13, and the paddy weeding robot 1 is turned to the left (S109). The traveling of the paddy field weeding robot 1 becomes a steep (small radius) arc as the azimuth difference increases, and a gentle (large radius) arc as the azimuth difference decreases.

  If “right rotation angle = left rotation angle” is not satisfied (S101: No), the process proceeds to step S102. For example, when the rotation angle on the left side is larger than that on the right side (S102: Yes), that is, as shown in FIG. 9C, the rice stock 41 is on the left side (relative to the traveling direction) from the center of the paddy weeding robot 1. If it is, the control unit 13 controls the drive units 11A and 11B to turn the paddy weeding robot 1 to the left in both directions (S103). Furthermore, when the rotation angle of the right sensor lever 23B is larger than that of the sensor lever 23A (S102: No), that is, as shown in FIG. If it is in the traveling direction), the driving unit 11A, 11B is controlled by the calculation unit 13 to turn to the right in the traveling direction (S104). Also in this case, the turning of the paddy weeding robot 1 becomes a sharper arc as the difference between the left and right rotation angles becomes larger, and becomes a gentler arc as the difference becomes smaller. When the processes in steps S103 and S104 are completed, the process proceeds to step S105, and the processes in steps S105 to S110 described above are executed again.

  In the case of a general paddy field, the rice stock 41 is regularly planted, and the number of rice stocks 41 does not differ greatly depending on the row or the row of the rice. The number of rice stocks 41 in the vertical and horizontal directions of the paddy field. By measuring, the size of the whole paddy field can be grasped. The position of the paddy weeding robot 1 can also be estimated from the number of strains in the vertical direction and the horizontal direction.

When the gyro sensor 27 detects that the rear part of the paddy field weeding robot 1 has been lowered (that is, tilted rearward) while the paddy field weeding robot 1 is traveling, the calculation unit 13 operates the lifting motors 14A and 14B. The first floats 20A and 20C are moved downward. Thereby, the paddy weeding robot 1 is corrected to the normal state (horizontal state). Conversely, when the gyro sensor 27 detects that the front part of the paddy field weeding robot 1 has been lowered (ie, tilted forward), the computing unit 13 operates the lifting motors 14A and 14B to operate the first float 20B, 20D is raised, and the paddy weeding robot 1 is tilted backward to assume a normal posture. Thereby, even if the paddy field is unstable soil, the paddy field weeding robot 1 can travel stably. Similarly, the paddy weeding robot 1 can maintain the normal state by controlling the first floats 20 </ b> A to 20 </ b> D to move up and down in response to changes in the horizontal direction of the paddy weeding robot 1.

  Furthermore, the paddy field weeding robot 1 can grasp the size of the paddy field by traveling in the paddy field, and can discriminate between the weeded area and the non-weeded area. This determination requires information on the traveling direction of the paddy weeding robot 1, and this information is acquired from the direction sensor 26 mounted on the paddy weeding robot 1.

(Detection of wrinkles)
Next, detection of wrinkles will be described. In order for the paddy weeding robot 1 to travel automatically across the entire paddy field, it is necessary to repeat the process of scanning the rice row and then moving to the next row of rice after detecting a row and moving again. This process will be described below.

  FIG. 11 is a flowchart showing the processing for detecting wrinkles of the paddy weeding robot. First, the calculation unit 13 acquires the rotation angles of the sensor levers 23A and 23B, that is, the voltage signal levels of the potentiometers 24A and 24B (S200). The calculation unit 13 checks the values of the voltage signals of the potentiometers 24A and 24B (S201). If both voltage values are equal to or greater than a predetermined rotation angle (S201: Yes), the bumper switch ( The state of the bumper SW) 25A, 25B is checked (S202). If the bumper switches 25A and 25B are both ON, it is determined that the vehicle is in a trap (S203). If it is dredging, the paddy weeding robot 1 is moved backward until the bumper switches 25A, 25B are returned (until turned OFF) (S204), and then turned 90 ° from the current direction (S205). If it is a turn-back process, it travels 90 ° (90 ° turning) so as to draw an arc (S206), enters the adjacent rice row as it is (S207), and performs rice row copying again. If the rotation angle of the sensor levers 25A, 25B has not reached a certain value in step S201 (S201: No), the process associated with wrinkle detection is terminated and the process returns.

  Further, when the paddy weeding robot 1 travels in the paddy field, it is necessary to map the paddy field. This mapping is performed using the rice buffer 32 (MAP [m] [n]) shown in FIG. The calculation unit 13 acquires information from the direction sensor 26 every time the paddy weeding robot 1 detects passage of the rice plant 41. The calculation unit 13 determines which traveling direction is east, west, south, and north. If the direction is north, the counter n is added. If the direction is south, the counter n is subtracted. If the direction is east, the counter m is added. If the direction is west, the counter m is subtracted. The count values of the counters m and n by this processing are stored as information on the rice stock 41 in the rice stock buffer 32 of the memory 31. This process is repeatedly executed every time the rice stock 41 is counted, whereby the shape of the paddy field, the weeded area, the non-weeded area, and the self-position of the paddy weeding robot 1 are calculated.

  When the paddy weeding robot 1 is traveling or at the end of the weeding operation, the rice plant buffer 32 is monitored by the computing unit 13, and if there is an unweeded area, traveling control is performed by the computing unit 13 so as to go to that place. Thereby, the paddy field weeding robot 1 can grasp the shape of the paddy field and can recognize its own position and the non-weeded area, so that stable weeding is performed without causing the non-weeded area.

(Effects of the first embodiment)
According to the paddy weeding robot 1 of the first embodiment, the sensor levers 23A and 23B, the potentiometers 24A and 24B and the calculation unit 13 autonomously run in the paddy field following the rice plant 41, and the weeds 41 are peeled off from the soil. Since the soil is stirred at the same time as it is killed, photosynthesis can be inhibited and the growth of new weeds 40 can be prevented. In addition, since the size and shape of the paddy field can be stored by autonomously traveling in the paddy field, and the weeded area and the non-weeded area can be discriminated, the entire paddy field can be efficiently weeded.

  Further, by the processing shown in FIG. 10, it is possible to run while confirming the positional relationship between the rice plant 41 and the paddy weeding robot 1 by the sensor levers 25A and 25B of the paddy weeding robot 1, and the rice plant 41 is always in the center of the paddy weeding robot 1. Since it passes so as to be located, it is possible to avoid stepping over the rice. Further, since the paddy weeding robot 1 can be made to follow the target direction, even if the wheels 19A and 19B slip and the traveling direction is temporarily mistaken, the traveling direction of the paddy weeding robot 1 can be corrected immediately. Can be.

  Further, the process shown in FIG. 11 allows the bumper switches 25A and 25B to contact the heel as the paddy weeding robot 1 moves to detect the heel so that the heel can be accurately detected without being affected by the shape of the heel. Can be detected.

[Second Embodiment]
FIG. 12 is a front view showing the configuration of the wheel of the second embodiment of the paddy weeding robot according to the present invention, in which (a) to (c) are changes in fins (movement) as the rotation proceeds. ). Although the wheel 19B is not shown in FIG. 12, it is the same as the wheel 19A. This embodiment is different from the first embodiment in the attachment state of the buns 18A and 18B to the wheels 19A and 19B, and the other configuration is the same as that of the first embodiment.

  Paddy fields are not uniform in shape and may be clayey soils that tend to get muddy. In such soil, the shape of the wheel shown in the first embodiment may be inappropriate. For example, if the fins 18A and 18B are buried in paddy soil more than expected and the amount of soil to be scraped increases, the load on the wheels 19A and 19B increases, which affects the traveling of the paddy weeding robot 1. become.

  In order to solve this problem, the present embodiment is provided with a fulcrum 33 that is provided on the surface of the wheel 19A (19B) at equal intervals in the circumferential direction and pivotally supports one end of each of the fins 18A. The plurality of first stoppers 34 provided near the outer periphery of the surface of the wheel 19A and the fulcrum 33 are provided on substantially the same circle, and the other ends of the plurality of fins 18A are engaged according to the rotation of the wheel 19A. And a second stopper 35 for stopping.

  The other end (free end) of the fin 18A is in contact with the first stopper 34 as shown in FIG. 12 (a) before contacting the soil. As the wheel 19A rotates, the fin 18A rotates and its free end is separated from the first stopper 34, and the free end is buried in the soil so as to be stuck in the soil. When the rotation of the wheel 19A further proceeds, as shown in FIG. 12B, the free end of the fin 18A starts rotating around the fulcrum 33 due to the resistance of the soil, and the free end is moved to the second stopper 35. Stop at the point of contact. At this time, if the second stopper 35 is arranged so that the fins 18A are substantially horizontal to the soil, the wheels 19A can be prevented from being buried more than necessary in the soil. When the rotation of the wheel 19A further proceeds from this state, the fin 18A is detached from the soil, but also at this time, the fin 18A is detached at a steep angle with respect to the soil surface, and as shown in FIG. Is not scraped up more than necessary, and the load on the rotation of the wheel 19A is reduced.

  According to the second embodiment, since the fins 18A and 18B provided on the wheels 19A and 19B can be rotated by the fulcrum 32, the wheels 19A and 19B are not buried in the soil more than necessary, and Since the soil is not scraped up more than necessary, the load on the rotation of the wheels 19A and 19B can be reduced, and the paddy weeding robot 1 can be driven stably.

[Third Embodiment]
13 is a perspective view of a third embodiment of the paddy weeding robot according to the present invention, FIG. 14 is a plan view of the paddy weeding robot shown in FIG. 1, FIG. 15 is a front view, and FIG. In the first embodiment, the paddy weeding robot 1 has a four-wheel configuration in which wheels 19A and 19B are front wheels, wheels 19C and 19D having smaller diameters are rear wheels, and sensor levers 23A and 23B, Instead of the potentiometers 24A, 24B and the bumper switches 25A, 25B, the second floats 50A, 50B that can be moved up and down, and the detection means arranged in a "<" shape attached to the upper portions of the second floats 50A, 50B The contactors 51A, 51B, 52A, and 52B are provided, and other configurations are the same as those of the first embodiment. In addition, with the change in the configuration described above, there is a part whose appearance is different from that of the first embodiment. Hereinafter, a novel part of the present embodiment will be described.

  The rear wheels 19C and 19D have a smaller diameter than the front wheels 19A and 19B, and the distance between the wheels is also smaller than the wheels 19A and 19B. As a result, the weeding width is about twice that of the first embodiment.

  The second floats 50A and 50B are arranged at the front part of the paddy field weeding robot 1, and are attached to the drive units 11A and 11B so as to be rotatable via link mechanisms 53A and 53B, as shown in FIG. As the links 530A and 530B of the link mechanisms 53A and 53B move up and down, they move in the vertical direction. The second floats 50A and 50B and the link mechanisms 53A and 53B are coupled to each other by a rotating shaft 54 (see FIG. 16), so that there is a slight amount between the second floats 50A and 50B and the link mechanisms 53A and 53B. It can be turned. Further, the second floats 50A and 50B are made of a material having a small specific gravity, such as urethane foam, so that the second floats 50A and 50B can be kept floating on the water surface. The second floats 50A and 50B are arranged with respect to the main frame 10 so that the height from the water surface WL (see FIG. 4) can be maintained substantially constant even if the posture of the paddy weeding robot 1 changes. It can be moved individually in the vertical direction. Note that the left contacts 51A and 51B and the right contacts 52A and 52B are electrically independent from each other in the traveling direction, and each of them is a signal processing unit 55 shown in FIG. Is electrically connected.

  By the way, the contacts 51A, 51B, 52A, 52B function as a capacitance sensor that detects a change in capacitance when contacting or approaching the rice plant 41, but these contact the floats 50A, 50B. Since it is attached, it is affected by the capacitance of the floats 50A and 50B. Therefore, contacts 58A and 58B for detecting the electrostatic capacities of the floats 50A and 50B are provided so that the rice stock 41 can be detected with higher accuracy. The contacts 58A and 58B are attached to the floats 50A and 50B as shown in FIGS. Further, the contacts 51A, 51B, 52A, 52B are attached so that the height from the water surface is the same as the contacts 51A, 51B, 52A, 52B.

  A controller 56 (see FIG. 18) that controls these is connected to the drive units 11A and 11B. The control device 56 includes the drive control unit 12, the calculation unit 13, the power supply unit 22, and the like illustrated in FIG. 5, and the azimuth sensor 26 and the signal processing unit 55 are connected to the calculation unit 13. The calculation unit 13, the power supply unit 22, the azimuth sensor 26, the capacitance sensor 55, and the like are housed in a housing 60, and a power switch 57 and a plurality of knobs for performing various settings are provided on the upper surface. Yes. Of the signal lines connected to the control device 56, the signal lines connected to the drive control unit 12 are grouped into cables 59A and 59B.

(Operation of paddy weeding robot)
Next, the operation of the paddy weeding robot 1 in the third embodiment will be described. FIG. 19 shows an example of the traveling locus of the paddy weeding robot 1. First, the operator carries the paddy weeding robot 1 into the paddy field desired to be weeded, and then positions (places) the paddy weeding robot 1 between the strips. Next, the power switch 57 of the control device 56 is turned on. When the power is turned on, the drive control unit 12 and the calculation unit 13 of the control device 56 start to operate, and data on the direction of travel (target direction) is input from the direction sensor 26. In addition, the capacitance detection signals from the contacts 51A, 51B, 52A, and 52B are input to the calculation unit 13, and the data value is used as a reference value.

  With the above processing, the drive motor 16 starts rotating, and the driving force is transmitted to the wheels 19A to 19D via gears (not shown), and the paddy weeding robot 1 starts running. The paddy field weeding robot 1 performs weeding with the fins 18A to 18D simultaneously with traveling. As shown in FIG. 19, the paddy field weeding robot 1 moves in the order of position A → position B → position C shown in FIG. Done continuously.

  FIG. 20 is a diagram showing the relationship between the contacts 51A, 51B, 52A, 52B of the paddy field weeding robot 1 and the rice plant 41. Here, it is assumed that the paddy weeding robot 1 is traveling from the lower side to the upper side of the drawing shown in FIGS. 19 and 20. When the rice plant 41 is at the center of the paddy weeding robot 1 (intermediate position between the contactor 51A and the contactor 51B) as shown in FIG. At this time, since it does not contact any of the contacts 51A and 51B, it proceeds toward the target direction of the direction sensor 26. Next, when the rice plant 41 is slightly on the right side (with respect to the traveling direction) of the paddy weeding robot 1 as shown in FIG. 51B is contacted. The capacitance of the contact 51B with respect to the ground changes, that is, the capacitance increases, due to the contact (or approach) of the rice plant 41 with the contact 51B. Therefore, the control device 56 turns the paddy weeding robot 1 in the right direction until the capacitance of the contact 51B returns to the reference value, that is, until the rice plant 41 and the contact 25B are separated. This turning is performed by reversing the right wheels 19B and 19D and rotating the left wheels 19A and 19D in the normal direction.

  Next, as shown in (c) of FIG. 20, when the rice plant 41 is slightly on the left side (relative to the traveling direction) of the paddy weeding robot 1, 41 contacts the contact 51A. By the contact (or approach) of the rice plant 41, the electrostatic capacity of the contact 51A increases. Therefore, the control device 56 turns the paddy weeding robot 1 in the left direction until the capacitance of the contact 51A returns to the reference value, that is, until the rice plant 41 and the contact 25A are separated. This arc movement is performed by increasing the rotation speed of the right wheels 19B and 19D with respect to the rotation speed of the left wheels 19A and 19C.

  Next, as shown in FIG. 20 (d), when the rice plant 41 is on the right side (relative to the traveling direction) larger than the center of the paddy weeding robot 1, the paddy weeding robot 1 will advance the rice plant by the subsequent progress. 41 contacts the contact 52B. The electrostatic capacity of the contact 52B is increased by the contact or approach of the rice plant 41. Therefore, the control device 56 causes the paddy weeding robot 1 to turn the paddy weeding robot 1 in the right direction until the electrostatic capacity of the contact 52B returns to the reference value, that is, until the rice plant 41 and the contact 52B are separated. This turning is performed by reversing the right wheels 19B and 19D and rotating the left wheels 19A and 19C in the normal direction.

  Similarly, as shown in FIG. 20 (e), when the rice plant 41 is on the right side (relative to the direction of travel) larger than the central portion of the paddy weeding robot, 41 contacts the contact 52B. The electrostatic capacity of the contact 52B increases due to the contact or approach of the rice plant 41. Therefore, the control device 56 turns the paddy weeding robot 1 in the left direction until the capacitance of the contact 52B returns to the reference value, that is, until the rice plant 41 and the contact 25B are separated. This turning is performed by reversing the left wheels 19A and 19C and rotating the right wheels 19B and 19D forward. By the operation described above, the paddy weeding robot 1 performs accurate copying of the rice row 41.

  Next, details of the control by the calculation unit 13 will be described with reference to a flowchart showing control of the paddy weeding robot 1 in FIG. After setting the paddy weeding robot 1 to a predetermined position, the power switch 57 of the control device 56 is turned on. First, the calculation unit 13 acquires the current direction from the direction sensor 26, and sets this as the target direction. Further, the current capacitance is acquired from the capacitance sensor 55, and this is set as a reference value (S300).

  Next, the calculation unit 13 monitors the change in the capacitance of the front contacts 52A and 52B of the weeding robot 1, and when both do not change with respect to the reference value (S301: None), that is, the rice plant 41 Is located at the center of the paddy field weeding robot 1 or farther away from the paddy field weeding robot 1, the process shifts to monitoring of the capacitance change of the inner contacts 51 </ b> A and 51 </ b> B (S <b> 305). If there is no change from the reference value in both capacitances, the process proceeds to reading of the azimuth angle (S309). The target azimuth is compared with the current azimuth (S310), and if there is no difference between them (S310: Yes), the arithmetic unit 13 controls the motors 16A and 11B so that the paddy weeding robot 1 travels straight ahead. (S314).

  The calculation unit 13 sets the current azimuth larger than the target azimuth in step S311 (a positive numerical value when tilting clockwise with respect to the target azimuth, and a negative numerical value when tilting counterclockwise (S311: In other words, when the paddy weeding robot 1 is tilted to the right with respect to the target direction, the calculating unit 13 controls the drive units 11A and 11B to turn the paddy weeding robot 1 leftward (S312). In this case, the traveling of the paddy weeding robot 1 becomes a steep arc as the difference in orientation becomes larger, and becomes a gentle arc as the difference in orientation becomes smaller.

  If there is a change between the capacitances of the contacts 52A and 52B of the weeding robot 1 and the reference value in step S311, the process proceeds to step S302. For example, when the change in the capacitance of the contact 52B is larger than the reference value (S302: Yes), that is, as shown in FIG. When the rice stock 41 is present, the operation unit 13 controls the drive units 11A and 11B to turn the paddy weeding robot 1 to the right (S303). Further, when the change in the capacitance of the contact 52B is larger than the reference value (S302: No), that is, as shown in FIG. 20 (e), the rice stock 41 is located on the left side from the center of the paddy weeding robot 1. In some cases, the drive units 11A and 11B are controlled by the calculation unit 31 to turn the paddy weeding robot 1 to the left (S304).

  If the capacitances of the contacts 51A and 51B inside the weeding robot change with respect to the reference value (S305: present), the process proceeds to step S306. For example, when the change in the capacitance of the contact 51B is larger than the reference value (S306: Yes), that is, as shown in FIG. 20 (b), the rice stock 41 is located on the right side of the center of the paddy weeding robot 1. In some cases, the calculation unit 13 controls the drive units 11A and 11B to turn the paddy weeding robot 1 to the right. (S307). Further, when the change in capacitance of the contact 26A is larger than the reference value (S306: No), that is, when the rice plant 41 is on the left side of the paddy weeding robot 1 as shown in FIG. The drive 11A and 11B are controlled by 31 to turn the paddy weeding robot 1 to the left. When the processes in steps S303 and S304 or steps S307 and S308 are completed, the process proceeds to step S309, and the processes in steps S309 to S314 described above are executed again.

  In step S301 and S305, the electrostatic capacity changes when the rice plant 41 comes into contact with any of the contacts 51A, 51B, 52A, 52B. The electrostatic capacity and the static of the contacts 58A, 58B change. It is determined that the weeding robot 1 is in contact with the rice plant 41 when the electric capacity is compared and the difference is generated. That is, in steps S301 and S305, it is determined whether or not there is a difference in capacitance between the contacts 51A, 51B, 52A, and 52B and the contacts 58A and 58B.

(Effect of the third embodiment)
According to the paddy field weeding robot 1 of the third embodiment, detection can be performed simply by touching the rice stock 41 with the contacts 51A, 51B, 52A, 52B, which are electrostatic capacitance sensors. Even if it exists, it can be detected.

  Furthermore, since the floats 50A and 50B to which the contacts 51A, 51B, 52A and 52B are attached are attached to the main frame 10 so as to be movable up and down, the water surface is not affected by the posture change of the paddy weeding robot 1 during traveling. Since the distance from WL can be kept constant, it is possible to detect a short rice immediately after transplanting, and stable autonomous running becomes possible.

  Further, by providing the contacts 58A and 58B for detecting the capacitances of the floats 50A and 50A, the contact is caused by the change in capacitance caused by the floats 50A and 50B coming into contact with the soil or the sudden change in posture of the robot. Even when the child is submerged, it is detected by the difference from the reference contact, so that the rice plant can be detected with high accuracy.

  Moreover, the paddy field weeding robot 1 having only the wheels 19A, 19B and the fins 18A, 18B is prevented from overlapping the wheels 19C, 19D and the fins 18C, 18D with respect to the wheels 19A, 19B and the buns 18A, 18B. The weeding width can be doubled.

[Other embodiments]
The present invention is not limited to the above embodiments, and various modifications can be made without departing from or changing the technical idea of the present invention. For example, in the first embodiment, the rice stock 41 in FIG. 9 is detected by the sensor levers 23A and 23B and the potentiometers 24A and 24B. However, the present invention is not limited to this. Any of the formulas may be used. Examples of the contact type include a tactile sensor and a limit switch. Furthermore, examples of the non-contact type include a photoelectric sensor, an ultrasonic sensor, an infrared distance sensor, and the like.

  In each of the above embodiments, the gyro sensor 27 is used as means for detecting the change in posture of the paddy weeding robot 1. However, for example, it can be replaced with an acceleration sensor, and the change in posture can be detected. If you can, you can substitute it. In addition, as the means for raising and lowering the first floats 20A to 20D, the raising and lowering motors 14A and 14B and the two screws 21 on the left and right are used, but only the first floats 20A to 20D can be moved up and down freely. For example, it is not limited to this configuration.

  In the first embodiment, the wheels 19 </ b> A and 19 </ b> B are shown as a pair, but can be increased to two or more pairs according to the size, weight, etc. of the main frame 10. Similarly, the third embodiment may be configured to have four or more wheels.

  In the third embodiment, when the floats 50A and 50B in FIG. 16 are attached to the main frame 10, the link mechanisms 53A and 53B are used to move in the vertical direction. However, the present invention is limited to this configuration. is not. For example, a configuration is conceivable in which a slidable bush is provided on a slide shaft provided in the vertical direction, and the slidable bush is movable in the vertical direction by being coupled thereto.

  Further, in the third embodiment, the two contactors 51A, 51B, 52A, and 52B are provided on the front side and the inner side of the left and right of the weeding robot. However, the contactor positions are provided at three or more locations. It is also possible to adopt a configuration in which the radius of arc travel (turning) is changed according to the control.

  The present invention can also be applied to farms other than paddy fields, for example, robots that remove weeds such as fields. Moreover, it is applicable also to places other than farmland, for example, a flower bed.

1 Paddy weeding robot 10 Main frame (main unit)
10a Space 11A, 11B Drive unit 12 Drive control unit 13 Calculation unit 14A, 14B Lifting motor 16 Driving motor 17 Gear (transmission mechanism)
18A, 18B, 18C, 18D Fins 19A, 19B, 19C, 19D Wheels 20A to 20D First float 21 Screw 22 Power supply unit 23A, 23B Sensor lever (contact)
24A, 24B Potentiometer (Rotation angle detection means)
25A, 25B Bumper switch (spot detector)
26 Azimuth sensor 27 Gyro sensor 28 Case 30 Control device 31 Memory 32 Rice plant buffer 33 Support point 34 First stopper 35 Second stopper 40 Weed 41 Rice plant 50A, 50B Second float 51A, 51B, 52A, 52B Contact (Capacitance sensor)
53A, 53B Link mechanism 54 Rotating shaft 55 Signal processing unit 56 Control device 57 Power switch 58A, 58B Contactor 59A, 59B Cable 60 Housing 230A, 230B Rotating shaft 530A, 530B Link

Claims (9)

A main body having a space in the center through which rice can pass;
A pair or a plurality of pairs of wheels provided at a lower portion of the main body;
A plurality of drive units for driving each of the wheels;
A pair of or a plurality of pairs of floats provided at the bottom of the body;
Detection means provided at the front of the main body for detecting rice lines;
A control device for controlling the rotation of the wheel via the drive unit so that the rice plant passes through the center of the space;
I have a,
The main body includes a direction sensor that detects a direction in which the main body is traveling,
The control device measures the number of rice lines that the main body passes to grasp the shape of the paddy field being weeded, and determines an unweeded area based on its own position information by the direction sensor. Paddy weeding robot. The main body includes a pair of paddy detectors for detecting paddy paddy at its front part,
2. The paddy weeding robot according to claim 1, wherein the control device controls the drive unit so that the wheels are reversed when the paddle detector detects paddy. 3. 3. The paddy weeding robot according to claim 1, wherein each of the pair or the plurality of pairs of wheels has a disk shape, and a plurality of fins are fixedly installed radially on one surface thereof. A main body having a space in the center through which rice can pass;
A pair or a plurality of pairs of wheels provided at a lower portion of the main body;
A plurality of drive units for driving each of the wheels;
A pair of or a plurality of pairs of floats provided at the bottom of the body;
Detection means provided at the front of the main body for detecting rice lines;
A control device for controlling the rotation of the wheel via the drive unit so that the rice plant passes through the center of the space;
Have
Each of the pair or plural pairs of wheels has a disc shape, and a plurality of fins provided radially on one side thereof, and one end of each of the plurality of fins is pivotally supported on one side. A plurality of fulcrum points, a plurality of first stoppers that are provided on the one side, and that engage the other ends of the plurality of fins on the outer peripheral side of the wheel according to the rotation state of the wheel, and are provided on the one side. And a plurality of second stoppers for locking the other ends of the plurality of fins on the inner peripheral side of the wheel according to the rotation state of the wheel. The driving unit includes a motor and, a transmission mechanism for transmitting the rotational force of the motor to the wheel, to any one of claims 1 to 4, characterized in that arranged in the lower portion of the body The paddy weeding robot described. A main body having a space in the center through which rice can pass;
A pair or a plurality of pairs of wheels provided at a lower portion of the main body;
A plurality of drive units for driving each of the wheels;
A pair of or a plurality of pairs of floats provided at the bottom of the body;
Detection means provided at the front of the main body for detecting rice lines;
A control device for controlling the rotation of the wheel via the drive unit so that the rice plant passes through the center of the space;
Have
The pair or plural pairs of floats are arranged before and after the pair or plural pairs of wheels, and the main body includes an elevating drive mechanism that individually raises and lowers each of the floats,
The said control apparatus controls a raising / lowering drive mechanism so that the attitude | position of the said main body will be in a normal state based on the detection information with respect to the change of the attitude | position from the normal state of the said main body, The paddy field weeding robot characterized by the above-mentioned. The detecting means is provided below the front part of the main body so as to be able to contact the rice plant, and one end of which rotates according to a contact state with respect to the rice plant, and the pair of contactors Rotation angle detecting means for outputting an electrical signal corresponding to each rotation state,
The control device compares two electrical signals according to the rotation angle of the pair of contacts by the rotation angle detecting means, and based on the difference value, the rice plant is positioned at the central portion of the main body. paddy weed robot according to any one of claims 1 to 6, wherein the controller controls the drive unit to. A main body having a space in the center through which rice can pass;
A pair or a plurality of pairs of wheels provided at a lower portion of the main body;
A plurality of drive units for driving each of the wheels;
A pair of or a plurality of pairs of floats provided at the bottom of the body;
Detection means provided at the front of the main body for detecting rice lines;
A control device for controlling the rotation of the wheel via the drive unit so that the rice plant passes through the center of the space;
Have
A pair of second floats that can be moved up and down separately from the floats provided at the lower part of the main body and provided on both sides of the front part of the main body,
A plurality of capacitance sensors provided in each of the second floats for detecting the rice plant by a change in capacitance;
A paddy weeding robot characterized by comprising: The plurality of capacitance sensors are:
At least a pair of first contactors disposed adjacent to each other in an electrically insulated state and installed in the second float so as to be in contact with the rice plant;
The second installed in the vicinity of the first contact of the second float in a state in which the rice plant cannot be contacted and is insulated from the first contact and the other components. Contactor, and
9. The capacitance detection value for the rice plant is defined as a difference between a capacitance change amount by the first contact and a capacitance change amount by the second contact. Paddy field weeding robot described in 1.

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