JP2019170222A - Autonomous travel system - Google Patents

Abstract

To provide an autonomous travel system capable of automatically and correctly registering a start point and an end point in a case of traveling along a straight path.SOLUTION: An autonomous travel system includes a reference path creation part, a position acquisition part, a travel control part, an elevation device, a float sensor, a ground sensor, an elevation control part, a start point registration part, and an end point registration part. The travel control part causes a rice transplanter to travel by autonomously performing at least steering along a straight path that is a path parallel to a reference path and connects a start point and an end point. The elevation control part calculates sinkage of a float on the basis of a detection result of the ground sensor to control the elevation device. The start point registration part registers, as the start point, a position when a grounding body contacts a field surface after a planting part descends after turning of the rice transplanter. The end point registration part registers, as the end point, an intersection of a line obtained by extending the start point in parallel with the reference path, and a line obtained by extending the start point of the straight path in one line before in perpendicular to the reference path.SELECTED DRAWING: Figure 8

Description

  The present invention mainly relates to an autonomous traveling system that autonomously performs steering at least along a straight path.

  Conventionally, a system for autonomously traveling a work vehicle along a previously created travel route is known. The travel route can be divided into, for example, a straight route and a turning route. Patent Document 1 discloses a system that causes a work vehicle to autonomously travel only on this straight path.

  In the rice transplanter of Patent Document 1, the operator sets the start point by operating the A button at the start of work, and sets the end point by operating the B button before the operator turns before the coasting area. Set. Moreover, this rice transplanter performs the process which estimates the next end point and start point, and produces a next straight path by translating the straight path which connects a start point and an end point. Patent Document 1 also describes setting instead of setting the start point and end point with buttons based on vehicle behavior such as ascent and descent of the seedling planting device.

  The rice transplanter of Patent Document 2 includes a float arranged in the vicinity of a seedling planting mechanism. In addition, the rice transplanter performs processing for detecting the start and end of work using the detection result of whether or not the float touches the field.

JP 2017-123829 A Japanese Unexamined Patent Publication No. 2016-21890

  As in Patent Literature 1, the start point and the end point set by the operator with buttons are likely to have large errors. However, even when the starting point and the ending point are set based on the vehicle behavior, it is difficult to accurately determine the starting point because, for example, it takes time to lower the working device. In addition, since the float shown in Patent Document 2 is generally attached with various members, the swing range is limited, and the swing range may change depending on the setting. The timing cannot be detected accurately.

  The present invention has been made in view of the above circumstances, and a main object thereof is to provide an autonomous traveling system capable of automatically and accurately registering a start point and an end point when traveling along a straight route. There is.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to an aspect of the present invention, an autonomous traveling system having the following configuration is provided. That is, the autonomous traveling system includes a reference route creation unit, a position acquisition unit, a traveling control unit, a lifting device, a float sensor, a ground sensor, a lifting control unit, a start point registration unit, and an end point registration. A section. The reference route creation unit creates a reference route. The said position acquisition part acquires the position of the rice transplanter provided with the planting part. The travel control unit uses the position of the rice transplanter acquired by the position acquisition unit to autonomously steer at least along a straight path that is parallel to the reference path and connects a start point and an end point. To go to the rice transplanter. The elevating device has a height of the planting part between a lowered state in which the planting part is lowered and the planting work is performed and an elevated state in which the planting part is raised and the planting work is not performed. To change. The float sensor detects a position of a float attached to the planting part in the lowered state. The grounding sensor detects the height of the grounding body attached to the planting part in the lowered state. The lift control unit calculates the amount of settlement of the float based on the detection result of the ground sensor, corrects the detection result of the float sensor, and based on the detection result of the float sensor after correction, the lift device To control. The start point registration unit registers a position when the grounding body comes into contact with the field surface after the planting unit is lowered after the rice transplanter is turned as the start point. The end point registration unit ends the intersection of a line obtained by extending the start point parallel to the reference path and a line obtained by extending the start point of the previous straight line path perpendicularly to the reference path. Register as a point.

  Thereby, the position where the planting part descend | falls is correctly detectable by using the detection result of a grounding sensor instead of a float. Therefore, the start point and the end point can be registered automatically and accurately. In addition, since the start point and the end point are registered using the sensors used in the control of the lift control unit, the number of parts and the cost can be reduced as compared with a configuration in which a separate sensor is provided.

  In the autonomous traveling system, when it is determined that the distance from the rice transplanter to the end point is equal to or less than a threshold value or exceeds the end point, a notification that the end point is near or exceeds the end point It is preferable to perform at least one of the speed reduction of the rice transplanter.

  Thereby, based on the end point registered in an accurate position, it can be notified that the end point is near (or exceeded), or the rice transplanter can be decelerated.

The side view of the rice transplanter with which the autonomous running system which concerns on one Embodiment of this invention is equipped. The top view of a rice transplanter. The side view which shows the mode of the planting part periphery. The perspective view which shows the rocking | fluctuation mechanism of a grounding body. The block diagram of an autonomous running system. The flowchart which shows the process which estimates the start point and the end point, and the process which produces a straight path | route. The figure which shows a mode that a reference | standard path | route is created based on start point A1 and end point B1. The figure which shows a mode that the end point B2 is estimated based on start point A1, start point A2, and a reference | standard path | route. The figure which shows a mode that the end point B3 is estimated based on start point A2, start point A3, and a reference | standard path | route. The flowchart which shows the process performed based on the distance to an end point.

  Next, embodiments of the present invention will be described with reference to the drawings. The autonomous traveling system 100 of this embodiment is a system for causing the rice transplanter 1 that performs rice planting (planting seedlings) in an agricultural field to perform autonomous traveling. Here, the autonomous traveling means that the rice transplanter 1 travels at least by autonomously steering. In the present embodiment, the operator makes settings related to autonomous traveling using the wireless communication terminal 7, and the rice transplanter 1 performs autonomous traveling based on the settings. Moreover, in this embodiment, although it is the structure which makes the rice transplanter 1 perform autonomous driving | running | working in an operator's boarding, the rice transplanter 1 which the operator has not boarded can also make autonomous driving | running | working.

  First, the rice transplanter 1 of this embodiment is demonstrated with reference to FIGS. FIG. 1 is a side view of the rice transplanter 1. FIG. 2 is a plan view of the rice transplanter 1. FIG. 3 is a side view showing a state around the planting unit 14. FIG. 4 is a perspective view showing the swing mechanism 90 of the grounding body 37. FIG. 5 is a block diagram of the autonomous traveling system 100. As shown in FIGS. 1 and 2, the rice transplanter 1 includes a vehicle body portion 11, a pair of left and right front wheels 12, a pair of left and right rear wheels 13, and a planting portion 14.

  An engine 22 is disposed inside the bonnet 21 disposed at the front portion of the vehicle body 11. The power generated by the engine 22 is transmitted to the front wheels 12 and the rear wheels 13 via the mission case 23. The power transmitted through the mission case 23 is also transmitted to the planting unit 14 through the PTO shaft 24 disposed at the rear part of the vehicle body unit 11. A driver's seat 25 on which an operator gets is provided at a position between the front wheel 12 and the rear wheel 13 in the front-rear direction of the vehicle body 11. A steering handle 26 for an operator to steer the rice transplanter 1 is disposed in front of the driver seat 25.

  The planting part 14 is connected to the rear of the vehicle body part 11 via an elevating link mechanism 31. The elevating link mechanism 31 has a parallel link structure including a top link 31a and a lower link 31b. An elevating cylinder (elevating device) 32 is connected to the lower link 31b. With this configuration, the entire planting unit 14 can be moved up and down by extending and lowering the lifting cylinder 32. Thereby, the height of the planting part is changed between a lowered state where the planting part 14 is lowered and the planting work is performed, and a raised state where the planting part 14 is raised and the planting work is not performed. Can be made. Moreover, although mentioned later for details, the height of the planting part 14 can also be adjusted according to the height, setting, etc. of an agricultural field. The elevating cylinder 32 is a hydraulic cylinder, but an electric cylinder may be used. Moreover, the structure which raises / lowers the planting part 14 by actuators other than a cylinder may be sufficient.

  The planting unit 14 mainly includes a planting input case 33, a plurality of planting units 34, a seedling mounting table 35, a plurality of floats 36, a grounding body 37, and a spare seedling table 38.

  Each planting unit 34 includes a planting transmission case 41 and a rotation case 42. Power is transmitted to the planting transmission case 41 via the PTO shaft 24 and the planting input case 33. A rotation case 42 is attached to each planting transmission case 41 on both sides in the vehicle width direction. Two planting claws 43 are attached to each rotating case 42 in the traveling direction of the rice transplanter 1. By these two planting claws 43, planting for one line is performed.

  As shown in FIG. 1, the seedling mounting table 35 is disposed in front of the planting unit 34 and is configured to be capable of mounting a seedling mat. The seedling stage 35 is configured to be capable of laterally moving in a reciprocating manner (slidable in the lateral direction). In addition, the seedling stage 35 is configured to be capable of intermittently feeding the seedling mat vertically downward at the reciprocating end of the seedling stage 35. With this configuration, the seedling stage 35 can supply seedlings of a seedling mat to each planting unit 34. Thus, the rice transplanter 1 can sequentially supply seedlings to the respective planting units 34 to continuously plant seedlings.

  The float 36 shown in FIG. 1 is swingably attached to the lower part of the planting part 14. The float 36 is arranged so that its lower surface can contact the field surface. By bringing the float 36 into contact with the field surface, the field before the seedling is planted is leveled. Moreover, the rear end of the float 36 is attached so that raising / lowering is possible, and the front end of the float 36 is supported so that rocking | fluctuation is possible. The swing angle of the float 36 is detected by a float sensor 68. The float rocking angle basically corresponds to the distance between the field surface and the planting part 14. The rice transplanter 1 basically operates by moving the elevating cylinder 32 using the feedback control so that the swing angle of the float 36 approaches the target angle and moving the planting unit 14 up and down. The ground height of the portion 14 can be kept constant. In addition, when the amount of water in the field is large and the field is soft, the float 36 is likely to sink into the field surface. On the other hand, when the amount of water in the field is small and the field is hard, the float 36 is unlikely to sink into the field surface.

  The grounding body 37 is swingably attached to the outside of the float 36 in the vehicle width direction. The grounding body 37 is substantially L-shaped in a side view (a shape having a portion extending along the field surface and a portion extending obliquely upward). Further, as shown in FIG. 4, the grounding body 37 has a shape (comb-like shape) in which elongated rod-like members are arranged. The grounding body 37 hangs downward due to its own weight, and swings along the uneven shape of the field surface. Compared with the float 36, the grounding body 37 reacts more sensitively to the uneven shape of the field surface. In other words, while the float 36 varies in the detection result according to the softness of the field, the grounding body 37 swings along the field surface regardless of the softness of the field.

  The grounding body 37 is supported so as to be swingable by a swinging mechanism 90 shown in FIGS. 3 and 4, and the grounding sensor 69 detects this swinging angle (angle θ in FIG. 3). Specifically, the pair of left and right grounding bodies 37 are fixed to a pair of left and right flat plate stays 91, respectively. These stays 91 are respectively fixed to a pair of left and right connecting members 92 bent into a crank shape. The pair of left and right connecting members 92 are connected by a swing shaft 93. The grounding body 37, the stay 91, and the connecting member 92 rotate integrally with the swing shaft 93 as a rotation axis.

  Further, a gear cover 94 is attached to the swing shaft 93 as shown in FIG. FIG. 4 shows the swing mechanism 90 with the gear cover 94 removed. That is, the first sector gear 95 is attached inside the gear cover 94. The first sector gear 95 rotates integrally with the swing shaft 93. The swing mechanism 90 includes a driven shaft 97 disposed in parallel with the swing shaft 93. A second sector gear 96 is attached to the driven shaft 97. The first sector gear 95 and the second sector gear 96 mesh with each other.

  With this configuration, the rocking shaft 93 rotates when the grounding body 37 rocks. Further, the driven shaft 97 rotates according to the rotation of the swing shaft 93. A sensor shaft 98 is fixed to the driven shaft 97. Therefore, the ground sensor 69 can detect the rotation angle of the driven shaft 97. Based on the rotation angle of the driven shaft 97, the rotation angle of the swing shaft 93 (that is, the swing angle) is detected. In the present embodiment, the angle directly detected by the ground sensor 69 is the rotation angle of the driven shaft 97, but may be the rotation angle of the swing shaft 93. Control performed based on the swing angle of the grounding body 37 will be described later.

  The spare seedling stand 38 is disposed outside the bonnet 21 in the vehicle width direction and can mount a seedling box containing a spare mat seedling. The upper portions of the pair of left and right auxiliary seedling stands 38 are connected to each other by a connecting frame 27 extending in the vertical direction and the vehicle width direction. A housing 28 is disposed at the center of the connecting frame 27 in the vehicle width direction. In the housing 28, a positioning antenna 61, an inertial measurement device 62, and a communication antenna 63 are arranged. The positioning antenna 61 can receive radio waves from positioning satellites constituting a satellite positioning system (GNSS). The position of the rice transplanter 1 can be acquired by performing a known positioning calculation based on this radio wave. The inertial measurement device 62 includes three gyro sensors (angular velocity sensors) and three acceleration sensors. By using the angular velocity and acceleration of the rice transplanter 1 detected by the inertial measuring device 62 as auxiliary means, the accuracy of the positioning result of the rice transplanter 1 is enhanced. The communication antenna 63 is an antenna for performing wireless communication with the wireless communication terminal 7.

  As shown in FIG. 5, the rice transplanter 1 includes a control unit 50. The control unit 50 is configured as a known computer and includes a CPU, a ROM, a RAM, an input / output unit, and the like (not shown). The CPU can read various programs from the ROM and execute them. Various programs and data are stored in the ROM. And the control part 50 can be operated as the memory | storage part 51, the travel control part 52, and the raising / lowering control part 53 by cooperation of said hardware and software. The control unit 50 may be a single piece of hardware or a plurality of pieces of hardware that can communicate with each other. In addition to the inertia measuring device 62 described above, a position acquisition unit 64, a communication processing unit 65, a vehicle speed sensor 66, and a rudder angle sensor 67 are connected to the control unit 50.

  The position acquisition unit 64 is electrically connected to the positioning antenna 61. The position acquisition unit 64 acquires the position of the rice transplanter 1 as, for example, latitude and longitude information from the positioning signal based on the radio wave received by the positioning antenna 61. The position acquisition unit 64 performs positioning using a known GNSS-RTK method after receiving a positioning signal from a reference station (not shown) by an appropriate method. However, instead of this, for example, positioning using a differential GNSS, single positioning, or the like may be performed. Alternatively, position acquisition based on radio wave intensity such as wireless LAN or position acquisition by inertial navigation may be performed.

  The communication processing unit 65 is electrically connected to the communication antenna 63. The communication processing unit 65 can perform modulation processing or demodulation processing by an appropriate method to transmit / receive data to / from the wireless communication terminal 7.

  The vehicle speed sensor 66 is disposed at an appropriate position of the rice transplanter 1, for example, at the axle of the front wheel 12. The vehicle speed sensor 66 is configured to generate a pulse corresponding to the rotation of the axle, for example. The detection result data obtained by the vehicle speed sensor 66 is output to the control unit 50.

  The steering angle sensor 67 is a sensor that detects the steering angle of the front wheels 12. The rudder angle sensor 67 is provided, for example, on a king pin (not shown) provided on the front wheel 12. The detection result data obtained by the steering angle sensor 67 is output to the control unit 50. The steering angle sensor 67 may be provided in the steering handle 26.

  The float sensor 68 is provided in a link mechanism that supports the rear end of the float 36 to detect a link height h0 and a swing mechanism that supports the front end of the float 36 and swings the float 36. And a sensor such as a potentiometer for detecting a moving angle. The link height h0 is the nail protrusion amount of the planting claw 43 (the distance between the tip of the planting claw 43 and the bottom surface of the float 36). In addition, the distance from the field surface to the planting part 14 can be detected from the swing angle of the float 36, and this distance includes the influence of the amount of settlement d of the float 36.

  The ground sensor 69 is a sensor such as a potentiometer that is provided in a swing mechanism that supports the ground body 37 and detects a swing angle of the ground body 37. Based on this swing angle, the distance from the field surface to the planting part 14 can be accurately detected.

  The travel control unit 52 performs vehicle speed control and steering control of the rice transplanter 1. The traveling control unit 52 can perform vehicle speed control and steering control at the same time, but can also perform only one of them. For example, when the traveling control unit 52 performs only the steering control, the vehicle speed is manually operated by the operator.

  Vehicle speed control is control which adjusts the vehicle speed of the rice transplanter 1 based on a predetermined condition. Specifically, the traveling control unit 52 determines the speed ratio of the transmission in the mission case 23 and the rotation of the engine 22 so that the current vehicle speed obtained from the detection result of the vehicle speed sensor 66 approaches the target vehicle speed. Change at least one of the speeds. The vehicle speed control includes control for stopping the rice transplanter 1 by setting the vehicle speed to zero.

  Steering control is control which adjusts the rudder angle of the rice transplanter 1 based on a predetermined condition. Specifically, the travel control unit 52 is provided, for example, on the rotating shaft (steering shaft) of the steering handle 26 so that the current steering angle obtained from the detection result of the steering angle sensor 67 approaches the target steering angle. Drive the steering actuator. The traveling control unit 52 may be configured to directly adjust the steering angle of the front wheels 12 of the rice transplanter 1 instead of the rotation angle of the steering handle 26.

  The raising / lowering control part 53 can control the height of the planting part 14 by controlling the raising / lowering cylinder 32 based on a predetermined condition. Detection results of the float sensor 68 and the ground sensor 69 are input to the elevation control unit 53. The elevation control unit 53 compares the detection result of the float sensor 68 (distance calculated based on the swing angle) with the detection result of the ground sensor 69 (distance calculated based on the swing angle). Thus, the subsidence amount d of the float 36 is calculated. The elevating control unit 53 further calculates the planting depth h by adding the settlement amount d and the link height h0. In this way, the settlement amount of the float sensor 68 is calculated from the detection result of the ground sensor 69, and the planting depth h can be calculated based on the settlement amount. By calculating the planting depth h, it can be determined whether or not the seedlings are appropriately planted. The raising / lowering control part 53 adjusts the height of the planting part 14 by controlling the raising / lowering cylinder 32 based on this determination result.

  The wireless communication terminal 7 is a tablet computer. The wireless communication terminal 7 includes a communication antenna 71, a communication processing unit 72, a display unit 73, an operation unit 74, and a control unit 80. The wireless communication terminal 7 is not limited to a tablet computer, and may be a smartphone or a notebook computer. The wireless communication terminal 7 performs various processes related to the autonomous traveling of the rice transplanter 1 as described later, but at least a part of this process can be performed by the arithmetic unit of the rice transplanter 1. Conversely, the wireless communication terminal 7 can also perform at least a part of various processes related to autonomous traveling performed by the rice transplanter 1.

  The communication antenna 71 is configured to include a short-distance communication antenna for performing wireless communication with the rice transplanter 1 and a portable communication antenna for performing communication using a mobile phone line and the Internet. The communication processing unit 72 is electrically connected to the communication antenna 71. The communication processing unit 72 can perform data transmission / reception with the wireless communication terminal 7 or other devices by performing modulation processing or demodulation processing by an appropriate method.

  The display unit 73 is a liquid crystal display, an organic EL display, or the like, and is configured to display an image. The display unit 73 can display, for example, information related to autonomous traveling, information related to the setting of the rice transplanter 1, detection results of various sensors, warning information, and the like. The operation unit 74 includes a touch panel and hardware keys. The touch panel is disposed so as to overlap the display unit 73 and can detect an operation with an operator's finger or the like. The hardware key is disposed on the side surface of the casing of the wireless communication terminal 7 or around the display unit 73 and can be operated by being pressed by the operator. The wireless communication terminal 7 may be configured to include only one of a touch panel and a hardware key.

  The control unit 80 is configured as a known computer and includes a CPU, a ROM, a RAM, an input / output unit, and the like (not shown). The CPU can read various programs from the ROM and execute them. Various programs and data are stored in the ROM. Then, by the cooperation of the hardware and software, the control unit 80 is changed to the storage unit 81, the start point registration unit 82, the end point registration unit 83, the reference route creation unit 84, the straight path creation unit 85, and the deceleration instruction unit 86. Can be operated as Processing performed by each unit of the control unit 80 will be described later.

  Next, with reference to FIG. 6 to FIG. 9, a process for causing the rice transplanter 1 to perform autonomous traveling along a straight path while registering the start point and the end point will be described. FIG. 6 is a flowchart showing a process for estimating a start point and an end point and a process for creating a straight path. 7 to 9 are schematic diagrams showing the flow at this time.

  In this embodiment, the start point and the end point are registered one after another, and the rice transplanter 1 is caused to autonomously travel along a straight path connecting them. The traveling control unit 52 performs steering autonomously along a straight path, and other processing (vehicle speed, turning, height of the planting unit 14, etc.) is operated by an operator. The start point is a position where the traveling along the straight path is started and a position where the planting operation is started. In addition, the end point is a position where a turn for completing the travel along the straight path and moving to the next straight path is performed, and also a position where the planting operation is finished.

  In the following description, the start point registered first is referred to as start point A1, and the start points registered thereafter are sequentially referred to as start point A2, start point A3,. Similarly, the end point registered first is referred to as end point B1, and the end points registered thereafter are sequentially referred to as end point B2, end point B3,.

  The wireless communication terminal 7 displays a screen for registering the start point by receiving an instruction for autonomous traveling along a straight route from the operator. On this screen, when the operator determines that the start point has been reached, a start point registration button for instructing the fact is displayed. Then, when the operator operates the start point registration button, the wireless communication terminal 7 (start point registration unit 82) registers the start point A1 (S101, FIG. 7). Specifically, the wireless communication terminal 7 (start point registration unit 82) indicates the position of the rice transplanter 1 at the time when the operator operates the start point registration button (the calculation result of the position acquisition unit 64 or a value obtained by correcting the position). Received from the rice transplanter 1 (control unit 50), and registers the position of the start point A1 (stored in the storage unit 81, and so on).

  Since the end point is not fixed at this point, the steering is also adjusted by the operator using the steering handle 26. Further, the operator starts planting work from the start point A1. And the end point registration button currently displayed on the radio | wireless communication terminal 7 is operated at the timing which reached the end point of the planting work. Thereby, the wireless communication terminal 7 (end point registration unit 83) registers the end point B1 (S102, FIG. 7). Specifically, the wireless communication terminal 7 (end point registration unit 83) receives the position of the rice transplanter 1 when the operator operates the end point registration button from the rice transplanter 1 (control unit 50). Register the position of B1.

  Thereby, the start point A1 and the end point B1 are registered. The wireless communication terminal 7 (reference route creation unit 84) creates a reference route by connecting them (S103, FIG. 7). The reference route is a route that determines the direction of a straight route that will be created later. In other words, the straight path is created so as to be parallel to the reference path.

  Note that the start point A1 and the end point B1 may be registered by the operator operating the operation unit provided in the rice transplanter 1 instead of the wireless communication terminal 7.

  Thereafter, the operator raises the planting unit 14, turns the rice transplanter 1 to reverse the direction of the rice transplanter 1, and lowers the planting unit 14 again. Here, conventionally, the next start point A2 is automatically registered based on the vehicle behavior of the rice transplanter 1, but the timing when the planting unit 14 descends to the position where the planting operation is performed or It is not easy to specify the position accurately. Although it is possible to detect this timing based on the detection result of the float sensor 68, the float 36 has a rocking range that changes depending on the setting of the planting depth or the influence of a member attached to the float 36. It is difficult to detect the timing accurately.

  In view of the above points, in the present embodiment, the timing at which the grounding body 37 contacts the field surface is registered as the next start point A2. Specifically, the wireless communication terminal 7 (start point registration unit 82) is configured to transfer the rice transplanter 1 at the timing when the detection result of the ground sensor 69 changes (the timing when the grounding body 37 comes into contact with the field surface and starts swinging). Is registered as the start point A2 (S104, FIG. 8).

  Next, the wireless communication terminal 7 (end point registration unit 83) performs processing for estimating the next end point B2. Specifically, the end point registration unit 83 sets an intersection point between a line L1 passing through the start point A2 and parallel to the reference path and a line L2 passing through the start point A1 and perpendicular to the reference path in plan view as the end point B2. Registration is performed (S105, FIG. 8).

  Next, the wireless communication terminal 7 (straight line creation unit 85) creates a straight path connecting the start point A2 and the end point B2, and instructs the rice transplanter 1 to autonomously travel along the straight path. (S106). The straight path created here is a line segment of the portion up to the end point B2 in the above-described line L1. As described above, the travel control unit 52 performs the above-described steering control so as to travel along this straight path.

  In addition, while performing autonomous traveling along a straight route, the wireless communication terminal 7 (deceleration instruction unit 86) performs the processing illustrated in FIG. FIG. 10 is a flowchart illustrating processing performed based on the distance to the end point. The wireless communication terminal 7 measures the distance from the rice transplanter 1 to the next end point (end point of the currently traveling straight route), and determines whether this distance is equal to or less than a threshold value (S201). When this distance is less than or equal to the threshold value, the deceleration instruction unit 86 notifies the operator that the end point is near and instructs the rice transplanter 1 (travel control unit 52) to decelerate. In addition, after estimating the end point, the wireless communication terminal 7 (end point registration unit 83) may transmit the position of the end point to the rice transplanter 1 and perform the control of FIG. 10 on the rice transplanter 1 side. The notification includes generating a warning sound, turning on a warning lamp, displaying a warning on the display unit 73 such as a tablet, and the like. Further, the deceleration includes stopping the rice transplanter 1. Thereby, it is possible to prevent the rice transplanter 1 from traveling beyond the end point. Note that an auxiliary threshold value larger than the above threshold value is set before the above processing, and the operator can be urged to turn at a timing when the distance to the end point becomes equal to or less than the auxiliary threshold value.

  Next, the operator raises the planting unit 14 in the vicinity of the end point B2 and turns again to reverse the direction of the rice transplanter 1. Then, after turning, the operator lowers the planting unit 14 again. Similarly to step S104, the wireless communication terminal 7 (start point registration unit 82) registers the timing at which the grounding body 37 contacts the field surface as the next start point A3 (S107, FIG. 9).

  Next, similarly to step S105, the end point registration unit 83 sets the intersection point of the line L3 passing through the start point A3 and parallel to the reference path and the line L4 passing through the start point A2 and perpendicular to the reference path to the end point B3. (S108, FIG. 9). Then, the straight route creation unit 85 creates a straight route that connects the start point A3 and the end point B3, and instructs the rice transplanter 1 to perform autonomous traveling along the straight route (S109). In addition, since the interval of each straight path depends on the turn performed by the operator, there is a variation in the interval, but it may be difficult to autonomously travel so that the intervals are uniform. Therefore, in this embodiment, the interval is not adjusted. .

  In this way, registration of the start point An based on the detection result of the ground sensor 69, estimation of the end point Bn based on the start point An and the start point An-1, creation of a straight path connecting the start point An and the end point Bn, and Autonomous driving is repeated. The end point is estimated based on an accurate start point based on the detection result of the ground sensor 69. Therefore, based on the end point indicating the accurate position, the operator can be urged to turn or the rice transplanter 1 can be decelerated.

  As described above, the autonomous traveling system 100 of the present embodiment includes the reference route creation unit 84, the position acquisition unit 64, the traveling control unit 52, the lifting cylinder 32, the float sensor 68, and the ground sensor 69. The elevating control unit 53, the start point registering unit 82, and the end point registering unit 83 are provided. The reference route creation unit 84 creates a reference route. The position acquisition unit 64 acquires the position of the rice transplanter 1 including the planting unit 14. The traveling control unit 52 uses the position of the rice transplanter 1 acquired by the position acquisition unit 64 to autonomously perform at least steering along a straight path that is parallel to the reference path and connects the start point and the end point. Go and make the rice transplanter 1 run. The raising / lowering cylinder 32 is located between the lowered state in which the planting part 14 is lowered and the planting work is performed, and the elevated state in which the planting part 14 is raised and the planting work is not performed. Change the size. The float sensor 68 detects the position of the float 36 attached to the planting unit 14 in the lowered state. The grounding sensor 69 detects the height of the grounding body 37 attached to the planting part 14 in the lowered state. The lift controller 53 calculates the amount of settlement of the float 36 based on the detection result of the ground sensor 69 to correct the detection result of the float sensor 68, and the lift cylinder 32 based on the corrected detection result of the float sensor 68. To control. The start point registration unit 82 registers the position when the grounding body 37 comes into contact with the field surface after the planting unit 14 descends after turning the rice transplanter 1 as a start point. The end point registration unit includes a line (line L1, line L3) in which the start point extends in parallel with the reference path and a line (line L2, line L4) in which the start point of the previous straight line path extends perpendicular to the reference path. ) And are registered as end points.

  Thereby, the position where the planting part 14 descend | falls can be correctly detected by using the detection result of the grounding sensor 69 instead of the float 36. Therefore, the start point and the end point can be registered automatically and accurately. In addition, since the start point and the end point are registered using the sensor (ground sensor 69) used in the control of the lift control unit 53, the number of parts and the cost can be reduced as compared with a configuration in which a separate sensor is provided.

  In addition, when the autonomous traveling system 100 of the present embodiment determines that the distance from the rice transplanter 1 to the end point is equal to or less than the threshold value or exceeds the end point, the end point is close or exceeds the end point. At least one of the notification of the effect and the deceleration of the rice transplanter 1 is performed.

  Thereby, based on the end point registered in the correct position, it can be notified that the end point is near (or exceeded), or the rice transplanter 1 can be decelerated.

  The preferred embodiment of the present invention has been described above, but the above configuration can be modified as follows, for example.

  In the above embodiment, a total of two grounding bodies 37 are arranged on both sides of the float 36 in the vehicle width direction, but may be one or three or more. Further, the grounding body 37 may be arranged so as to line up with the float 36 in the front-rear direction.

  In the above embodiment, when traveling on a straight route, the traveling control unit 52 controls only steering, but a configuration in which vehicle speed control is further performed may be employed.

  In the above embodiment, the rice transplanter 1 and the wireless communication terminal 7 perform wireless communication, but may be configured to perform wired communication.

1 Rice transplanter 7 Wireless communication terminal 32 Lift cylinder (lifting device)
52 travel control unit 64 position acquisition unit 82 start point registration unit 83 end point registration unit 84 reference route creation unit 85 linear route creation unit 86 deceleration instruction unit 100 autonomous travel system

Claims (2)

A reference route creation unit for creating a reference route;
A position acquisition unit for acquiring the position of the rice transplanter equipped with a planting unit;
Using the position of the rice transplanter acquired by the position acquisition unit, the rice transplanter performs at least steering autonomously along a straight path that is parallel to the reference path and connects a start point and an end point. A travel control unit that travels,
A lifting device that changes the height of the planting part between a lowered state in which the planting part is lowered and the planting work is performed and an elevated state in which the planting part is raised and the planting work is not performed. When,
A float sensor for detecting the position of the float attached to the planting part in the lowered state;
A grounding sensor for detecting the height of the grounding body attached to the planting part in the lowered state;
A lift control unit that calculates the settlement amount of the float based on the detection result of the ground sensor, corrects the detection result of the float sensor, and controls the lifting device based on the corrected detection result of the float sensor When,
A start point registration unit for registering the position when the grounding body comes into contact with the field surface after the planting unit is lowered after turning the rice transplanter as the start point;
End point registration for registering the intersection point of a line extending the start point parallel to the reference path and a line extending the start point of the previous straight line perpendicular to the reference path as the end point And
An autonomous traveling system comprising: The autonomous traveling system according to claim 1,
When it is determined that the distance from the rice transplanter to the end point is equal to or less than a threshold value or exceeds the end point, a notification that the end point is near or exceeds the end point, and deceleration of the rice transplanter An autonomous traveling system characterized by performing at least one of the processes.

Images