Field water level management system

Abstract

To provide a field water level management system that prevents outflow of a coating material to solve the problem in which a field water level management system including a control unit that controls a water supply valve and a drainage valve installed in a field uses a granular fertilizer coated with plastic or the like during rice planting operations and the like, causing an environmental problem of the coating material flowing out into rivers, but prevention of outflow of the coating material has not been considered.SOLUTION: In a field water level management system in which a water supply device 1 and a drainage device 2 of a field F are controlled by a management server 6, a coating material of a fertilizer floating on a water surface is identified by an image analysis from image data of the field F acquired by a small aircraft, or occurrence of the coating material of the fertilizer floating on the water surface is predicted by displaying at least the fertilizer application amount of the previous year in gradation for each area of the field F, and the coating material of the fertilizer floating in the field F is recorded in a map database and displayed on a monitor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a water level management system for a farm field. [Background technology]

[0002] There is a water level control system for a farm field that includes an actuator that operates a water supply valve and a drain valve installed in the farm field, and a control unit that controls the actuator (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-099321 Summary of the Invention [Problem to be solved by the invention]

[0004] However, at present, granular fertilizers coated with synthetic resins such as plastic are widely used in fields during rice planting and other operations, and environmental problems have been raised regarding the synthetic resin coating being washed away into rivers, but no consideration has been given to preventing the outflow of the synthetic resin coating used for the fertilizer.

[0005] The present invention has been made in view of the above, and an object of the present invention is to provide a water level management system for farm fields that prevents the synthetic resin used as a coating material for fertilizer from leaking out. [Means for solving the problem]

[0006] The invention described in claim 1 is a field water level management system that controls the water supply device 1 and drainage device 2 of field F using a management server 6, and uses image analysis to identify fertilizer covering material A floating on the water surface from image data of field F acquired by a small airplane 15, or displays at least the previous year's fertilizer application amount in shades for each area of ​​field F to predict the occurrence of fertilizer covering material A floating on the water surface, and records fertilizer covering material A floating in field F in a map database and displays it on a monitor.

[0007] The invention described in claim 2 is a water level management system for a field described in claim 1, in which when the water level in field F is higher than a predetermined water level and the drainage device 2 drains water to the predetermined water level, if a predetermined amount or more of fertilizer covering material A floating on the water surface is detected, the drainage speed by the drainage device 2 is slowed down below the normal speed.

[0008] According to the invention described in claim 2, in a field F where a predetermined amount of fertilizer covering material A floating on the water surface is present, the floating covering material A can be prevented from flowing out by slowing the drainage speed below the normal speed.

[0009] The invention described in claim 3 is a field water level management system described in claim 2, which sets a start time Tc for plowing work, rice planting work, etc. for each field F, displays the start times Tc in chronological order on a monitor such as a management server 6 or a mobile terminal 5, and drains the water to the predetermined water level using a drainage device 2 when the water level in field F is higher than the predetermined water level. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an overall schematic diagram of a water level control system according to an embodiment of the present invention. [Figure 2] This is a schematic diagram of the entire area around the field. [Figure 3] 1 is a graph for explaining drainage. [Figure 4] 1 is a graph for explaining drainage. [Figure 5] FIG. 1 is a plan view of an electric riding rice transplanter. [Figure 6] FIG. 2 is a perspective view of the front of the electric riding rice transplanter. [Figure 7] FIG. 4 is a side view for explaining the operation of the shift lever and the potentiometer. [Figure 8] FIG. 4 is a side view for explaining the operation of the potentiometer. [Figure 9] 1 is a map of a field showing nitrogen levels. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the water level control system for a farm field disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that, although an example in which the water supply device 1 and the drainage device 2 are separate devices will be described, it goes without saying that a water supply and drainage device that serves both water supply and drainage may also be used, and the present invention is not limited to the embodiment shown below.

[0012] Figure 1 is an overall schematic diagram showing a water supply device 1 that fills field F with water, a drainage device 2 that drains water from field F, a water level sensor 3 that measures the water level in field F, an Internet communication network wireless repeater 4, a mobile terminal 5 such as a tablet or smartphone operated by a worker, and a management server 6.

[0013] Figure 2 is a schematic diagram of the entire fields F1 to F12 in which the water supply device 1 and drainage device 2 are installed, the water channels W (intake channels, drainage channels), and the farm roads R, and shows a small aircraft 15 (hereinafter referred to as drone 15) such as a drone or small agricultural helicopter flying along a predetermined route above each of the fields F1 to F12.

[0014] The water supply device 1 is equipped with an electric water supply pump 7 at the bottom that draws up water from a water channel W, and a water supply valve 8 that is opened and closed by an electric motor that puts the water drawn up by the electric water supply pump 7 into a field F, and is equipped with a solar panel 9 and a power storage device (battery) at the top that supply power to the electric motor that opens and closes the electric water supply pump 7 and the water supply valve 8.

[0015] The drainage device 2 is equipped at its bottom with an electric drainage pump 10 that sucks up water from the field F and a drainage valve 11 that is opened and closed by an electric motor that drains the water sucked up by the electric drainage pump 10 into a waterway W, and at its top with a solar panel 9 and a power storage device (battery) that supply power to the electric motor that opens and closes the electric drainage pump 10 and the drainage valve 11.

[0016] The water level sensor 3 has its lower part inserted into the field F near the water supply device 1, and measures the water depth with an electrode at its lower part. Electricity to the water level sensor 3 is supplied from the water supply device 1.

[0017] The internet communication network wireless repeater 4 is installed near the farm field F, and allows the water supply device 1, the drainage device 2, the water level sensor 3 and the management server 6 to share information (commands) with each other via the internet.

[0018] The mobile terminal 5 is a commonly available tablet, and shares information (commands) with the management server 6 via the Internet.

[0019] The management server 6 is installed inside a base house, stores a map database in which the fields F1 to F12 owned by the user are registered, and has a field water level management system. It receives water level information from the water level sensor 3 and real-time precipitation forecast information from weather information, and issues commands to the water supply device 1 and drainage device 2 to manage water supply and drainage.

[0020] The drone 15 is equipped with a camera and flies above the entire surface of each of the fields F1 to F12 along a predetermined route set by the management server 6 or the mobile terminal 5, acquiring image data of each of the fields F1 to F12 and transmitting the image data to the management server 6.

[0021] <Control of field water level management system> Currently, granular fertilizer coated with synthetic resin A such as plastic is widely used to fertilize fields during rice planting work, and environmental problems have arisen with the synthetic resin A used as the coating material flowing into rivers.

[0022] Therefore, the present invention provides a water level control system for farm fields that prevents the synthetic resin A, which is a coating material for fertilizer, from leaking out.

[0023] That is, the field water level control system controls the water levels of the fields F1 to F17 as follows.

[0024] First, when carrying out rice planting work or the preceding work of tilling, the electric motor of the water supply device 1 of each field F1 to F17 is operated to open the water supply valve 8 and operate the electric water supply pump 7 to fill each field F1 to F17 with water to a predetermined level based on water level information from the water level sensor 3, and then the drone 15 is flown over the entire surface of each field F1 to F12 along a predetermined route to acquire image data of each field F1 to F12 and send it to the management server 6.

[0025] The management server 6 performs image analysis on the image data of each of the fields F1 to F12 that the drone 15 acquires and transmits by flying a predetermined route over the entire surface of each of the fields F1 to F12, identifies the synthetic resin A that is the covering material floating on the water surface of each of the fields F1 to F12, and records the synthetic resin A that is the covering material floating in each of the fields F1 to F12 in the map database (for example, as shown for field F2 in Figure 2).

[0026] In addition, a worker may look at the image sent from drone 15 and manually input synthetic resin A, which is a covering material floating in each of the fields F1 to F12 in the map database, on management server 6 or mobile terminal 5, or may walk around each of the fields F1 to F12 and manually input synthetic resin A, which is a covering material floating in each of the fields F1 to F12 in the map database, on mobile terminal 5.

[0027] In addition, the amount of fertilizer applied for at least the last year is displayed in shades of gray for each of the fields F1 to F12 in the map database (for example, displayed in shades of gray as shown in field F5 in Figure 2), and the amount of synthetic resin A, which is the floating covering material, is predicted (this prediction may also be made taking into account the amount of fertilizer applied for the past two to three years).

[0028] For example, if the amount of fertilizer applied last year was large, it is determined that the amount of floating covering material, synthetic resin A, was also large.

[0029] Then, the worker inputs the rice planting start time (or puddling start time) Tc for each of the fields F1 to F12 into the management server 6 or the mobile terminal 5.

[0030] The management server 6 then records the rice planting start time (or puddling start time) Tc for each of the fields F1 to F12 in chronological order and displays it on the monitor of the management server 6 or the mobile terminal 5.

[0031] Next, if the water level H1 of each field F1 to F12 is higher than the predetermined water level H2 (H2') suitable for rice planting (or plowing), the management server 6 or the mobile terminal 5 drains the water from each field F1 to F12 to the predetermined water level H2 (H2') suitable for rice planting (or plowing), and both automatic drainage control and manual drainage operation can be performed.

[0032] In the case of manual drainage operation, the electric drainage pump 10 and drainage valve 11 of the drainage device 2 of each field F1 to F12 are manually operated so that drainage is completed to the predetermined water level H2 (H2') at the drainage completion time Tb, a predetermined time before the rice planting start time (or puddling start time) Tc for each field F1 to F12 in chronological order displayed on the monitor of the management server 6 or the mobile terminal 5. The water level of each field F1 to F12 is measured by each water level sensor 3 and displayed sequentially on the monitor of the management server 6 or the mobile terminal 5.

[0033] In field F, which has a large amount of floating covering material, synthetic resin A, the amount of drainage per unit time is reduced to prevent floating covering material, synthetic resin A, from flowing into the river.

[0034] In this case, taking into account the drainage completion time Tb, the discharge start time Ta' for a field F with a large amount of floating covering material synthetic resin A is set earlier than the discharge start time Ta for a field F with a small amount of synthetic resin A (see Figure 3).

[0035] The discharge start times Ta and Ta' are set based on the following discharge time T, which is the time it takes for the water level H1 before discharge to reach a predetermined water level H2 (H2').

[0036] Discharge time T = drainage volume Q of field H / efficiency Q' of electric drainage pump 10 The drainage volume of field H, Q = (H1-H2) x field area Therefore, the discharge start time Ta, Ta' = Tb - T Furthermore, in field F, which has a large amount of floating covering material, synthetic resin A, the predetermined water level H2' at the drainage completion time Tb is set to a level lower than the normal predetermined water level H2, thereby preventing floating covering material, synthetic resin A, in field H from flowing into the river during rice planting and plowing work (see Figure 4).

[0037] In the case of automatic drainage control, the management server 6 or the mobile terminal 5 sets the discharge start times Ta and Ta' so that drainage is completed to a predetermined water level H2 (H2') at the drainage completion time Tb, a predetermined time before the rice planting start time (or puddling start time) Tc for each of the chronologically ordered fields F1 to F12, and controls the electric drainage pumps 10 and drainage valves 11 of the drainage devices 2 for each of the fields F1 to F12 in sequence. The water levels in each of the fields F1 to F12 are measured by the respective water level sensors 3 and transmitted to the management server 6 or the mobile terminal 5, and the management server 6 or the mobile terminal 5 controls drainage based on the water level data for each of the fields F1 to F12.

[0038] The discharge start times Ta and Ta' are set based on the following discharge time T, which is the time it takes for the water level H1 before discharge to reach a predetermined water level H2 (H2').

[0039] Discharge time T = drainage volume Q of field H / efficiency Q' of electric drainage pump 10 The drainage volume of field H, Q = (H1-H2) x field area Therefore, the discharge start time Ta, Ta' = Tb - T The management server 6 and the mobile terminal 5 then determine whether or not there is a large amount of synthetic resin A, which is the floating covering material, in each of the fields F1 to F12, by one of the following three means.

[0040] The first method involves performing image analysis on the image data of each field F1 to F12 acquired and transmitted by drone 15 flying a predetermined route over the entire surface of each field F1 to F12, identifying synthetic resin A, which is a covering material floating on the water surface of each field F1 to F12, recording synthetic resin A, which is a covering material floating in each field F1 to F12, in a map database, and determining whether there is a large amount of synthetic resin A, which is a floating covering material.

[0041] The second method involves an operator looking at the images sent from the drone 15 and manually inputting the synthetic resin A, which is a covering material floating in each of the fields F1 to F12 in the map database, on the management server 6 or mobile terminal 5, or walking around each of the fields F1 to F12 and manually inputting the synthetic resin A, which is a covering material floating in each of the fields F1 to F12 in the map database, on the mobile terminal 5, and determining whether there is a large amount of synthetic resin A, which is a covering material floating in each of the fields F1 to F12, from the input data of synthetic resin A, which is a covering material floating in each of the fields F1 to F12.

[0042] The third method is to display the amount of fertilizer applied for at least the last year in shades of gray for each field F1 to F12 in the map database, predict the amount of floating synthetic resin A, which is a covering material, and determine whether there is a large amount of floating synthetic resin A.

[0043] If field F is determined to have a large amount of floating synthetic resin A, a covering material, using any of the three methods described above, drainage control will be implemented to reduce the amount of drainage per unit time, thereby preventing the floating synthetic resin A from flowing into the river.

[0044] In this case, taking into account the drainage completion time Tb, the discharge start time Ta' for a field F with a large amount of floating covering material, synthetic resin A, is set to be earlier than the discharge start time Ta for a field F with a small amount (see Figure 3).

[0045] Furthermore, in field F where it is determined that there is a large amount of floating covering material, synthetic resin A, the predetermined water level H2' at the drainage completion time Tb is set to a water level lower than the normal predetermined water level H2, thereby preventing floating covering material, synthetic resin A, in field H from flowing into the river during rice planting or tilling work (see Figure 4).

[0046] <Other embodiments>

[0047] (1) Figures 5 to 8 show an electric riding rice transplanter used for rice planting in a farm field F.

[0048] As shown in FIG. 5, the electric riding rice transplanter has a seedling planting device 103 attached to a traveling body 100 by a lifting link device, and is also provided with a fertilizer application device 104.

[0049] The vehicle body 100 is a four-wheel drive vehicle having a pair of front wheels 106, 106 and a pair of rear wheels 107, 107, which are drive wheels.

[0050] In this specification, the left and right sides of the riding rice transplanter when viewed in the forward direction are referred to as the left and right sides, respectively, and the forward direction is referred to as the front side and the backward direction is referred to as the rear side.

[0051] The traveling vehicle body 100 has a transmission case 111 and an electric motor 112 arranged on a main frame, a hydraulic pump 113 integrally assembled with the transmission case 111 on the rear side of the transmission case 111, and a front cover 114 protruding from the front upper part of the transmission case 111.

[0052] A steering handle 116 is provided at the upper end of the front cover 114. A step floor 119, which serves as a floor for operation, is attached to the top of the aircraft body, and a pilot's seat 120 is installed above the electric motor 112.

[0053] The electric motor 112 is covered by a rear cover 119a that is integrally formed in a convex shape extending upward from the step floor 119, and a driver's seat 120 is installed on the rear cover 119a.

[0054] A gearshift lever 117 is provided on the side of the steering handle 116.

[0055] The front wheels 106, 106 are journaled on a front wheel support case that is provided on the side of the transmission case 111 so that its direction can be changed. The left and right rear wheels 107, 107 are mounted on rear wheel drive shafts of rear wheel transmission cases 121, 121 attached to both left and right ends of the left and right frames. The left and right frames are supported on the rear end of the main frame.

[0056] The rotational power of the electric motor 112 is transmitted to the input shaft of a hydrostatic continuously variable transmission (hereinafter referred to as HST) 131 via a drive pulley, a transmission belt, and a driven pulley in this order, and is then transmitted from the output shaft of the HST 131 to the inside of the transmission case 111.

[0057] The rear ends of the rear output shafts 111a, 111b protrude rearward from the transmission case 111, and these protruding ends are connected to left and right rear wheel transmission shafts 135, 135 that transmit power to the rear wheel transmission cases 121, 121. The left and right rear wheel transmission shafts 135, 135 are configured to drive and rotate the left and right rear wheels 107, 107, respectively.

[0058] The driving force is transmitted from the transmission case 111 via a drive shaft to a PTO transmission case provided at the rear of the running body 100, and the driving force is transmitted from the PTO transmission case to each fertilizer delivery section of the fertilizer application device 104 via a fertilizer application drive mechanism, and the driving force is also transmitted to the seedling planting device 103 via the PTO transmission shaft.

[0059] As shown in Figures 6 to 8, the speed change lever 117 is an HST operating lever that operates the HST trunnion of the HST 131, and is operated to a forward position, a neutral position, and a reverse position, and is provided with a potentiometer 150 that detects the operating position.

[0060] When the speed change lever 117 is operated to the neutral position, the potentiometer 150 detects that it has been operated to the neutral position, and the control device operates the HST trunnion to neutralize the output of the HST 131 (stop the output).

[0061] The further the speed change lever 117 is operated from the neutral position toward the forward position, the more the potentiometer 150 detects the amount of operation toward the forward position, and the control device operates the HST trunnion in accordance with the amount of operation toward the forward position, increasing the forward output of the HST 131 and increasing the forward speed.

[0062] The further the shift lever 117 is operated from the neutral position toward the reverse position, the more the potentiometer 150 detects the amount of operation toward the reverse side, and the control device operates the HST trunnion in accordance with the amount of operation toward the reverse side, increasing the reversing force of the HST 131 and increasing the reverse speed.

[0063] In addition, a brake pedal 186, which serves as a vehicle stopping operation device and is provided at the front of the traveling vehicle body 100, can operate both the main clutch and the left and right rear wheel brake devices (not shown), and is located on the lower right side of the steering handle 116. When this brake pedal 186 is depressed, the main clutch is disengaged, and then the left and right rear wheel brakes are applied, bringing the vehicle to a stop.

[0064] The brake pedal 186 is provided with a general pedal lock device that maintains the pedal in a depressed state.

[0065] An operating lever 186a, which is connected to the brake pedal 186 by a link mechanism 186b, is provided so as to extend forward beyond the front end of the vehicle body. That is, when an operator positioned at the front of the vehicle body presses down on the operating lever 186a, the brake pedal 186 is depressed by the link mechanism 186b, the main clutch is disengaged, and then the left and right rear wheel brakes are applied, bringing the vehicle to a halt.

[0066] In addition, a front arm 188 protrudes from the front end of the aircraft body, and a center mascot 189 is provided behind the front arm 188.

[0067] The front arm 188 is used when moving the riding rice transplanter over ridges.

[0068] The driver seated in the operator's seat 120 gets out of the traveling body 100 and positions himself in front of the traveling body 100, grasps the front arm 188 and puts his weight on it to prevent the front part of the traveling body 100 from lifting up when crossing the ridge, and operates the slow-speed forward lever 190 equipped on the front arm 188 to move the riding rice transplanter forward at a slow speed to cross the ridge.

[0069] As shown in FIG. 6, the slow forward movement lever 190 is provided below the center of the left and right upper side 188a of a front arm 188 that is gate-shaped when viewed from the front.

[0070] As shown in Figures 6 to 8, when the slow forward speed lever 190 is gripped and operated, the potentiometer 150, which detects the operating position of the speed change lever 117 via the operating wire 191, is also used to operate the HST trunnion, causing the HST 131 to enter a slow forward speed state.

[0071] The operation of the slow forward movement lever 190 will now be described.

[0072] The speed change lever 117 is supported by an operation unit support stay 200 whose base is fixed to the main frame so as to be freely rotatable back and forth, and a rotating stay 201 having a potentiometer 150 attached thereto is provided on the operation unit support stay 200 so as to be freely rotatable about a pivot shaft 201a, and one end of a tension spring 202 is engaged with the operation unit support stay 200, and the tip of the tension spring 202 is engaged with the upper part of the rotating stay 201, so that the rotating stay 201 is biased and held in contact with a stopper 203 provided to prevent it from rotating upward around the pivot shaft 201a.

[0073] An end of an operating wire 191 of the slow forward movement lever 190 is engaged with the lower part of the rotating stay 201 .

[0074] Therefore, when the slow forward movement lever 190 is not gripped and operated, the rotating stay 201 is rotated upward by the biasing force of the tension spring 202 and is biased and held in a state in which it abuts against the stopper 203 .

[0075] An engagement pin 117 a provided at the tip of an arm that rotates when the speed change lever 117 is operated engages with an elongated hole in a detection arm 150 a of the potentiometer 150 , and the operation of the speed change lever 117 is detected by the potentiometer 150 .

[0076] Then, when the speed change lever 117 is operated to the neutral position just before the ridge in order to cross it (the vehicle's progress is stopped just before the ridge), and the slow forward lever 190 is gripped and operated, the operating wire 191 is pulled, causing the rotating stay 201 to rotate downward against the biasing force of the tension spring 202, and the potentiometer 150 detects the same detection value as when the speed change lever 117 is operated to slow forward (because the engagement pin 117a is fixed when the speed change lever 117 is in the neutral position, the rotating stay 201 rotates downward, causing the detection arm 150a of the potentiometer 150 to rotate and detect the same detection value as when it is operated to slow forward), actuating the HST trunnion, putting the HST 131 into a slow forward state, and the vehicle moves forward at slow speed.

[0077] When the machine has finished crossing a ridge while moving forward at slow speed, or when the machine becomes unstable due to tilting, etc., by releasing the grip on the slow-speed forward lever 190, the operating wire 191 loosens and the force of the tension spring 202 causes the rotating stay 201 to rotate upward. The potentiometer 150 detects that the speed change lever 117 has been operated to the neutral position, and activates the HST trunnion to neutralize the output of the HST 131 (stop the output), bringing the machine to a halt.

[0078] In addition, when the speed change lever 117 is operated to a speed slower than the speed at which the slow forward speed lever 190 is gripped and operated to move forward slowly, it is safer for the control device to control the slow speed of the speed change lever 117 to take priority.

[0079] On the other hand, the initial setting of the potentiometer 150 is performed by setting the sensor to zero with the speed change lever 117 in the neutral position and the slow speed forward lever 190 released (not being gripped), by setting the operating range of the slow speed forward lever 190 with the speed change lever 117 in the neutral position and the slow speed forward lever 190 fully gripped, and by operating the speed change lever 117 to the maximum speed with the slow speed forward lever 190 released (not being gripped), by setting the operating range of the speed change lever 117.

[0080] The seedling planting device 103 is attached to the traveling vehicle body 100 by a lifting link device so that it can be raised and lowered freely.

[0081] The upper end of the piston of a general lift cylinder, the base of which is rotatably mounted on the traveling body 100, is connected to a lifting link device, and a hydraulic pump 113 mounted on the traveling body 100 supplies and discharges pressurized oil to the lift cylinder through a lifting valve (not shown), thereby extending and retracting the piston of the lift cylinder, thereby moving the seedling planting device 103 connected to the lifting link device up and down.

[0082] The seedling planting device 103 is comprised of a planting transmission case 138, which doubles as a frame and is mounted to the rear of the lifting linkage in a rolling manner; a seedling carrier 139, which is supported by supports on the planting transmission case 138 and moves back and forth from side to side to carry seedlings and supply seedlings one by one to the seedling outlet 139a of each row; a seedling planting tool 141, which is mounted to the rear end of the planting transmission case 138 and removes the seedlings supplied to the seedling outlet 39a at the bottom of the carrier 139 one by one and plants them in the field; and a center (sensor) float 142 and a side float 143, which are ground leveling devices whose rear parts are pivotally supported on the bottom of the planting transmission case 138 and whose front parts are mounted so that they can swing up and down. The center float 142 and side float 143 are provided to level the front of the field where the seedlings will be planted by the seedling planting tool 141.

[0083] The PTO transmission shaft has universal joints at both ends and is provided to transmit power from the transmission case 111 to the planting transmission case 138 of the seedling planting device 103.

[0084] An angle-of-attack sensor (not shown) provided at the front of the center float 142 detects the height of the seedling planting device 103 above the ground, and based on the detection value of the angle-of-attack sensor, the control device controls the lifting valve and the lift cylinder controls the up and down position of the seedling planting device 103.

[0085] In other words, when the angle of attack sensor detects that the front of the center float 142 has been lifted above the appropriate range by an external force, the hydraulic pump 113 pumps pressurized oil from inside the transmission case 111 into the lift cylinder, causing the piston to protrude and the lifting link device to move upward, thereby raising the seedling planting device 103 to a predetermined position; and when the angle of attack sensor detects that the front of the center float 142 has fallen below the appropriate range, the pressurized oil in the lift cylinder is returned to inside the transmission case 111, causing the lifting link device to move downward and lowering the seedling planting device 103 to a predetermined position.

[0086] When the front of the center float 142 is within the appropriate range (when the detection value of the angle of attack sensor is within the appropriate range and the seedling planting device 103 is at the appropriate height above the ground), the flow of pressurized oil in and out of the lift cylinder is stopped, and the seedling planting device 103 is held in a fixed position.

[0087] In this way, the center float 142 is used as a ground sensor for automatic height control of the seedling planting device 103.

[0088] The fertilizer application device 104 discharges a fixed amount of fertilizer from the fertilizer tank 167 downward by each fertilizer delivery section, and the discharged fertilizer is transported by a blower 169 through each fertilizer hose to the fertilizer application guides attached to each float 142, 43, and then dropped into fertilizer application furrows formed near the sides of the seedling planting rows by furrow making bodies provided in front of each fertilizer application guide, thereby distributing granular fertilizer throughout the field.

[0089] (2) We will explain the fertilizer amount correction of the variable fertilizer control of a typical variable fertilizer rice transplanter, which detects the sowing distribution of green manure (hairy vetch) cultivated before rice planting and the fertility of the field at the time of rice planting, and changes the amount of fertilizer according to the fertility level.

[0090] In agricultural ICT, which displays the topography of a field, the yield, and the growing condition of the field using yield combines and Zarubio fertilization in shades of gray on a map, the previous year's yield condition and the lodging condition are displayed in shades of gray on the map.

[0091] For example, when harvesting with a combine, green manure (hairy vetch) seeds are sown in areas other than where the rice plants have fallen.

[0092] This will set the amount of nitrogen per specified weight for a specific variety of green manure (hairy vetch) in the area where the green manure (hairy vetch) seeds are sown.

[0093] The theoretical amount of nitrogen per unit area calculated by multiplying the set amount of nitrogen by the seeding rate is displayed in shades on a map (see Figure 9).

[0094] When rice planting and fertilizing work is being carried out using a variable fertilizer rice transplanter in the above-mentioned shaded areas, variable fertilization control is performed to reduce the amount of fertilizer applied according to the amount of nitrogen compared to the amount applied for the detected fertility (correction control is performed on the fertility sensor if fertilization underground is not complete). [Explanation of symbols]

[0095] 1 Water supply device 2 Drainage device 5. Mobile devices 6 Management Server 15 Small aircraft (drone) A Covering material (synthetic resin) F field Tc Start time of plowing and rice planting

Claims

1. A water level management system for a field in which a water supply device (1) and a drainage device (2) of a field (F) are controlled by a management server (6), characterized in that the system uses image analysis to determine fertilizer covering material (A) floating on the water surface from image data of the field (F) acquired by a small airplane (15), or predicts the occurrence of fertilizer covering material (A) floating on the water surface by displaying at least the amount of fertilizer applied in the previous year in shades for each area of ​​the field (F), and records the fertilizer covering material (A) floating in the field (F) in a map database and displays it on a monitor.

2. 2. A water level management system for a field according to claim 1, characterized in that when the water level in the field (F) is higher than a predetermined water level and the drainage device (2) drains water to the predetermined water level, if a predetermined amount or more of fertilizer covering material (A) floating on the water surface is detected, the drainage speed by the drainage device (2) is slower than the normal speed.

3. A field water level management system as described in claim 2, characterized in that a start time (Tc) for plowing work, rice planting work, etc. for each field (F) is set, the start times (Tc) are displayed in chronological order on a monitor of a management server (6) or a mobile terminal (5), etc., and when the water level in the field (F) is higher than a predetermined water level, the drainage device (2) drains the water to the predetermined water level.

Images