Turning control device

Abstract

To minimize positional deviation during turning.SOLUTION: A turning control device 400 that controls automatic turning of a crawler vehicle 1 having left and right traveling crawlers 350L, 350R, includes: a turning control unit 411 that controls the left and right crawlers 350L, 350R to cause the crawler vehicle 1 to perform pivot turning; and a detection unit 412 that detects a turning angle. The turning control unit 411 executes control by alternately changing axes of the pivot turning each time the detected turning angle reaches a set divided turning angle obtained by dividing a preset turning angle at a predetermined ratio.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a turning control device. [Background technology]

[0002] A tracked vehicle generally has crawlers on both sides for traveling, and is known as a vehicle that can achieve high traveling performance on rough terrain. Currently, tracked vehicles that use electric motors as a power source are also becoming popular.

[0003] Known methods of turning in a tracked vehicle equipped with tracks include a super pivot turn, in which the rotation of the left and right crawlers is controlled and the vehicle turns around the center of the tracked vehicle as an axis, and a pivot turn, in which one track is stopped and only the other track is rotated, causing the vehicle to turn around the stopped track as an axis.

[0004] However, in a pivot turn, although the positional deviation during the turn is small, there is a problem in that the torque during the turn increases. That is, in a pivot turn, there is little positional deviation during the turn, but when turning between the furrows of a farm field, for example, a large torque is required because the vehicle turns while pushing a mass of soil.

[0005] Furthermore, in a pivot turn, the torque required for turning is small, but the positional deviation is large. That is, in a pivot turn, the turning radius is large because the vehicle turns around either the left or right crawler as an axis, and the positional deviation after a 90-degree turn, for example, is large.

[0006] In response to the above-mentioned problems, a turning control device has been disclosed that automatically turns a tracked vehicle equipped with crawlers for running on the left and right sides, and that includes an acquisition unit that acquires the load values ​​of the power sources of the left and right crawlers, a turning control unit that controls the left and right crawlers to make the tracked vehicle make a pivot turn or a yaw turn until the tracked vehicle faces the target direction, and a movement control unit that temporarily suspends the pivot turn or yaw turn performed by the turning control unit each time the load value reaches a predetermined value, and controls the left and right crawlers to move the tracked vehicle forward or backward a predetermined distance (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2023-128168 Summary of the Invention [Problem to be solved by the invention]

[0008] However, with the technology described in Patent Document 1, turning is temporarily stopped and the robot moves forward or backward a predetermined distance, which causes a positional shift when moving forward or backward, and because the robot moves forward or backward once, there is a risk of hitting the ridges when turning between the rows of a farm field. Furthermore, in order to rotate, it is necessary to prepare furrows with sufficient width, but there is also the issue that widening the furrow spacing reduces the yield per field area. This requires minimizing positional deviations during turning.

[0009] SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a turning control device that minimizes positional deviations during turning. [Means for solving the problem]

[0010] Form 1: One or more embodiments of the present invention propose a turning control device that controls the automatic turning of a tracked vehicle equipped with crawlers for running on the left and right sides, and includes a turning control unit that controls the left and right crawlers to make a pivot turn of the tracked vehicle, and a detection unit that detects a turning angle, and the turning control unit proposes a turning control device that performs control by alternately changing the axis of the pivot turn each time the detected turning angle becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio.

[0011] Form 2: One or more embodiments of the present invention propose a turning control device that controls the automatic turning of a tracked vehicle equipped with crawlers for running on the left and right sides, and includes a turning control unit that controls the left and right crawlers to make gentle turns of the tracked vehicle, and a detection unit that detects a turning angle, and the turning control unit proposes a turning control device that performs control by alternately changing the axis of the gentle turn each time the detected turning angle becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio.

[0012] Mode 3: One or more embodiments of the present invention propose a swing control device that includes a locking mechanism that mechanically locks the crawler that serves as an axis during swing, and a locking mechanism control unit that controls the locking mechanism.

[0013] Feature 4: One or more embodiments of the present invention propose a swing control device in which the crawler does not have a lug.

[0014] Mode 5: One or more embodiments of the present invention propose a swing control device that stops the crawler that needs to be stopped during the pivot swing by exciting the driving motor or mechanically locking it using the locking mechanism.

[0015] Form 6: One or more embodiments of the present invention propose a turning control device in which the turning control unit repeats small-angle turns during pivot turns, and for the small-angle turns, the turning control is performed by a method including a method of setting the rotation speed of the driving motor in advance, a method of measuring the rotation angle using an angular acceleration sensor, a method of detecting the current direction using multiple GNSSs, or a method of detecting the current direction using a geomagnetic sensor. [Effects of the Invention]

[0016] According to one or more embodiments of the present invention, positional deviation during turning is minimized, which has the effect of preventing a decrease in the yield per field area. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram showing the configuration of a tracked vehicle according to a first embodiment of the present invention. [Figure 2] 1 is a diagram showing the configuration of a turning control device for a tracked vehicle according to a first embodiment of the present invention. [Figure 3] 3 is a flowchart showing the processing of the turning control device in the tracked vehicle according to the first embodiment of the present invention. FIG. [Figure 4] 1A to 1C are diagrams showing the turning operation of a tracked vehicle according to a first embodiment of the present invention in time series. [Figure 5] FIG. 4 is a diagram showing the configuration of a tracked vehicle according to a second embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing the configuration of a turning control device for a tracked vehicle according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a flowchart showing the processing of a turning control device in a tracked vehicle according to a second embodiment of the present invention. [Figure 8] 6A to 6C are diagrams showing the turning operation of a tracked vehicle according to a second embodiment of the present invention in time series. DETAILED DESCRIPTION OF THE INVENTION

[0018] The tracked vehicle 1 will be described with reference to FIGS. In the following, an agricultural robot will be described as an example of the tracked vehicle 1.

[0019] First Embodiment A tracked vehicle 1 according to this embodiment will be described with reference to FIGS. 1 to 4. FIG.

[0020] <Configuration of Tracked Vehicle 1> As shown in FIG. 1, the tracked vehicle 1 according to this embodiment includes a sensor system group 100, a storage battery 200, a drive system group 300, and a turning control device 400. The storage battery 200 is a power source that supplies the necessary power to the sensor system group 100, the drive system group 300, and the turning control device 400.

[0021] <Configuration of the sensor system group 100> As shown in FIG. 1, the sensor system group 100 includes a camera 110, a distance sensor 120, an IMU 130, a motor rotation speed measurement device 140, a first GNSS 150, a second GNSS 160, and a geomagnetic sensor 170.

[0022] The camera 110 captures an image of the surroundings of the tracked vehicle 1. One or more cameras 110 are installed on the tracked vehicle 1, and at least one camera 110 installed on the tracked vehicle 1 is positioned in front of the tracked vehicle 1 and captures images in the forward direction (direction of travel) of the tracked vehicle 1. The camera 110 may be an RGB camera, an infrared camera, an RGBD camera that can also obtain distance information (described later), or a combination of these cameras as appropriate. Image data captured by the camera 110 is transmitted to a turning control device 400, which will be described later.

[0023] The distance sensor 120 is a sensor that acquires information about the distance to a predetermined object. In this embodiment, the distance sensor 120 acquires distance information for determining whether or not the tracked vehicle 1 (for example, a robot) will collide with an obstacle. The distance information obtained by the distance sensor 120 is also used together with the camera image to obtain depth information for each pixel and generate a distance image. The distance information obtained by the distance sensor 120 is transmitted to the turning control device 400, which will be described later.

[0024] The IMU 130 is composed of an angular acceleration sensor that acquires angular acceleration of roll, pitch, and yaw angles, and a three-dimensional acceleration sensor in the X, Y, and Z directions, and detects posture information of the tracked vehicle 1. The attitude information of the tracked vehicle 1 obtained by the IMU 130 is transmitted to a turning control device 400, which will be described later.

[0025] The motor rotation speed measurement device 140 detects the rotation speed or rotation angle of motors 330L and 330R (to be described later) that drive left and right crawlers 350L and 350R (to be described later) of the tracked vehicle 1. The rotation speed or rotation angle of the motors 330L, 330R that drive left and right crawlers 350L, 350R (to be described later) of the tracked vehicle 1 obtained by the motor rotation speed measurement device 140 is transmitted to a turning control device 400 (to be described later).

[0026] The first GNSS 150 acquires position information of the tracked vehicle 1 based on signals received from satellites. In this embodiment, two GNSSs, a first GNSS 150 and a second GNSS 160, are used to detect the orientation of the tracked vehicle 1 from the position information of each. The position information of the tracked vehicle 1 obtained from the first GNSS 150 and the second GNSS 160 is transmitted to a turning control device 400, which will be described later.

[0027] The geomagnetic sensor 170 detects the orientation of the tracked vehicle 1 based on the geomagnetism. By using the first GNSS 150, the second GNSS 160, and the geomagnetic sensor 170 in combination, it becomes possible to detect the orientation of the tracked vehicle 1 even in a space where radio waves are blocked, for example.

[0028] <Configuration of drive system group 300> As shown in FIG. 1, the drive system group 300 includes motor drivers 310L and 310R, locking mechanisms 320L and 320R, motors 330L and 330R, power transmission mechanisms 340L and 340R, and crawlers 350L and 350R.

[0029] The motor drivers 310L and 310R supply energy to the motors 330L and 330R to rotate them. Specifically, the motors 330L and 330R are supplied with desired energy based on a control signal from a motor control unit 415, which will be described later.

[0030] The locking mechanisms 320L, 320R receive excitation signals for locking from the motor drivers 310L, 310R in order to electrically lock the left and right crawlers 350L, 350R that are rotated by drive wheels, which will be described later. In addition, the locking mechanisms 320L, 320R drive actuators (not shown) mounted on the power transmission mechanisms 340L, 340R (described later) to mechanically lock the left and right crawlers 350L, 350R, which rotate due to the drive wheels (described later). By using any of the above methods, the crawlers 350L and 350R that should be stopped during a pivot turn are maintained in a stopped state.

[0031] The motors 330L, 330R transmit power to power transmission mechanisms 340L, 340R, which will be described later, for moving the left and right crawlers 350L, 350R, which are rotated by the drive wheels. The motors 330L and 330R are electric motors, such as three-phase AC motors.

[0032] The power transmission mechanisms 340L and 340R are transmission mechanisms for moving the left and right crawlers 350L and 350R, and are configured with, for example, a belt, a reducer, and the like. The power transmission mechanisms 340L, 340R transmit the driving force supplied from the motors 330L, 330R to the drive wheels, and the rotation of the drive wheels causes the left and right crawlers 350L, 350R to rotate. If the objective is to improve hill-climbing performance, it is preferable that the left and right crawlers 350L, 350R do not have lugs, which are irregularities attached thereto. In other words, by eliminating the lugs on the left and right crawlers 350L and 350R, friction with the soil during turning is reduced, improving sliding and reducing turning torque.

[0033] <Configuration of the turning control device 400> As shown in FIG. 2, the turning control device 400 includes a processor 410 and a memory 420.

[0034] In this embodiment, the processor 410 controls each part in the turning control device 400 based on information from each sensor constituting the sensor system group 100, and performs autonomous operation of the moving body. In this embodiment, the processor 410 executes obstacle detection processing, turning control, and the like based on information such as distance image information from the camera 110 and the distance sensor 120, for example.

[0035] The memory 420 is composed of a ROM, a RAM, or the like, and saves and stores control programs and various data. The memory 420 is provided with a storage unit 421, which saves and stores information such as a target turning angle and position information for turning, which are necessary for the processor 410 to perform turning control.

[0036] <Configuration of the processor 410> As shown in Figure 2, the processor 410 of the turning control device 400 of this embodiment is configured to include a turning control unit 411, a detection unit 412, a locking mechanism control unit 413, an image processing unit 414, a motor control unit 415, and a driving control unit 416. The turning control unit 411, the detection unit 412, the lock mechanism control unit 413, the image processing unit 414, the motor control unit 415, the travel control unit 416, etc. are connected via a bus line BL as shown in FIG.

[0037] The turning control unit 411 determines the turning axis for the pivot turn based on the detection result from the detection unit 412, which will be described later. The turning control unit 411 determines the left and right crawlers 350L, 350R to be rotated and the direction of rotation based on the turning axis information determined for turning control, and executes control for pivot turning. More specifically, the turning control unit 411 alternately changes the axis of pivot turning and executes control each time the turning angle detected by the detection unit 412 described later becomes a set divided turning angle obtained by dividing a preset set turning angle into a predetermined ratio. Furthermore, the turning control unit 411 repeats turning at a small angle during a pivot turn. For small angle turns, the turning control unit 411 performs turning control by a method including setting the rotation speed of the driven motors 330L and 330R in advance, measuring the rotation angle using an angular acceleration sensor, detecting the current direction using the first GNSS 150 and the second GNSS 160, and detecting the current direction using the geomagnetic sensor 170.

[0038] The detector 412 detects the turning angle. In this embodiment, the detection unit 412 detects the turning angle by using, for example, two GNSSs, a first GNSS 150 and a second GNSS 160, and detecting the orientation of the tracked vehicle 1 from the respective position information. In this embodiment, the detection unit 412 may detect the turning angle by detecting the orientation of the tracked vehicle 1 from sensor information from the geomagnetic sensor 170, for example.

[0039] The lock mechanism control unit 413 transmits a signal for operating the lock mechanisms 320L, 320R to lock the crawlers 350L, 350R on the rotating shaft side.

[0040] The image processing unit 414 executes image processing for detecting objects (for example, harvested products, obstacles, weeds, etc.) from image information captured by the camera 110. In this embodiment, for example, when the tracked vehicle 1 is a harvesting robot, the image processing unit 414 extracts an image of the harvested product from the captured image information. Furthermore, the image processing unit 414 calculates the size and position of the object based on, for example, image information captured by the camera 110 and distance information obtained from the distance sensor 120 through arithmetic processing.

[0041] The motor control unit 415 transmits drive signals to the motor drivers 310L and 310R that drive the left and right crawlers 350L and 350R, based on information from the travel control unit 416, which will be described later.

[0042] Based on the signal from the turning control unit 411 and the information from the sensor system group 100, the driving control unit 416 determines whether the tracked vehicle 1 should move forward, backward, or turn, and transmits a control signal based on the determination to the motor control unit 415.

[0043] <Processing of the turning control device 400> The turning process of the turning control device 400 according to this embodiment will be described with reference to FIGS. In the following, an example will be described in which the target angle is set to 90 degrees and the tracked vehicle 1 is turned left.

[0044] The turning control unit 411 determines the turning axis for the pivot turn (step S110). If the processing has been continued up to this point, the rotation control unit 411 reverses the rotation axis. The rotation axis information determined by the rotation control unit 411 is transmitted to the lock mechanism control unit 413 via the bus line BL. When the process of step S110 ends, processor 410 transitions the process to step S120.

[0045] The lock mechanism control unit 413 transmits a locking signal to the lock mechanisms 320A, 320B of the swivel shafts to operate the lock mechanisms 320A, 320B of the swivel shafts in order to lock the crawlers 350L, 350R determined by the swivel control unit 411. Then, the locking mechanisms 320A and 320B lock the crawlers 350L and 350R of the rotating shaft based on the signal received from the locking mechanism control unit 413 (step S120). The crawlers 350L and 350R of the rotation shaft may be locked by exciting the motors 330A and 330B, or by mechanical locking. When the process of step S120 above ends, processor 410 transitions the process to step S130.

[0046] For the purpose of turning control, the turning control unit 411 performs processing to determine the left and right crawlers 350L, 350R to be rotated and the direction of rotation in order to rotate the tracked vehicle 1 around the determined turning axis (step S130). For example, when turning left, the motor 330R of the right crawler 350R is rotated in the forward direction with the left crawler 350L as the rotation axis. Also, when turning left, if the turning shaft is the right crawler 350R, the left crawler 350L is rotated in the backward direction. For example, when turning right, the motor 330L of the left crawler 350L is rotated in the forward direction with the right crawler 350R as the rotation axis. Also, when turning right, if the turning shaft is the left crawler 350L, the right crawler 350R is rotated in the backward direction. The turning control unit 411 transmits the above information to the traveling control unit 416 via the bus line BL in accordance with the turning direction. The traveling control unit 416 transmits a control signal to the motor control unit 415 based on information from the turning control unit 411 . When the motor control unit 415 receives a control signal from the travel control unit 416, it transmits a drive signal to the motor drivers 310L, 310R that drive the left and right crawlers 350L, 350R, causing the left and right crawlers 350L, 350R to rotate and perform a turning operation. When the process of step S130 ends, processor 410 transitions the process to step S140.

[0047] The detection unit 412 measures the turning angle based on sensor information obtained from the first GNSS 150 and the second GNSS 160, for example. The turning control unit 411 calculates a set divided turning angle according to the turning angle and the division ratio based on the measurement data in the detection unit 412 (step S140). Here, the turning angle is the cumulative turning angle from the start of turning to the time turning has been performed, and the set divided turning angle is the angle at which the turning axis is set and the next turning axis is set. In addition, in this embodiment, the allowable value of the turning angle is the target angle of 90 degrees. When the process of step S140 above ends, processor 410 transitions the process to step S150.

[0048] The turning control unit 411 compares the turning angle with the target angle. If the turning control unit 411 determines that the turning angle is greater than the target angle ("NO" in step S150), it ends all processing. On the other hand, if turning control section 411 determines that the turning angle is equal to or less than the target angle ("YES" in step S150), processor 410 transitions the process to step S160.

[0049] Next, the turning control unit 411 determines whether or not the turning angle has reached a predetermined set divided turning angle (step S160). If the turning control unit 411 determines that the turning angle has not reached the predetermined set divided turning angle ("NO" in step S160), it transitions the process to step S130 to continue the turning process. On the other hand, when it is determined that the turning angle has reached the predetermined set divided turning angle ("YES" in step S160), the turning control section 411 shifts the processing to step S170.

[0050] The turning control unit 411 temporarily suspends the turning operation (step S170), and then transitions the process to step S110. In other words, using Figure 4, which shows the turning behavior of the tracked vehicle 1 when the number of divisions is 3 (a 90-degree turn and the set divided turning angle (target angle) is 30 degrees), the turning control unit 411 changes the direction of the tracked vehicle 1 by 90 degrees from the direction before turning by performing all of the above processing in each step from step 1 (operation from Figure 4(A) to Figure 4(B)) in which the tracked vehicle 1 reaches the first set divided turning angle (first target angle) from its orientation before turning, step 2 (operation from Figure 4(B) to Figure 4(C)) in which the first set divided turning angle (first target angle) reaches the second set divided turning angle (second target angle), and step 3 (operation from Figure 4(C) to Figure 4(D)) in which the second set divided turning angle (second target angle) reaches the third set divided turning angle (third target angle).

[0051] <Actions and Effects> As explained above, the turning control device 400 of the tracked vehicle 1 in this embodiment controls the automatic turning of the tracked vehicle 1 equipped with running crawlers 350L, 350R on the left and right, and includes a turning control unit 411 that controls the left and right crawlers 350L, 350R to make the tracked vehicle 1 make a pivot turn, and a detection unit 412 that detects the turning angle, and the turning control unit 411 alternately changes the axis of the pivot turn each time the turning angle detected by the detection unit 412 becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio, thereby performing control. In other words, the turning control unit 411 makes the tracked vehicle 1 make a pivot turn, and when the turning angle detected by the detection unit 412 becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio, the axis of the pivot turn is alternately changed and control is performed. This makes it possible to minimize positional deviations when the tracked vehicle 1 turns. Therefore, for example, even if the tracked vehicle 1 is an agricultural robot whose purpose is to harvest crops planted in ridges created in farmland or remove weeds, when it turns between the ridges in a farm field, part of the tracked vehicle 1 will not hit the ridges and cause part of the ridge to collapse, so the ridges can be arranged while ensuring a minimum amount of space for the tracked vehicle 1 as an agricultural robot to run or turn. Therefore, the yield per field area can be maintained or improved.

[0052] The turning control device 400 of the tracked vehicle 1 in this embodiment includes locking mechanisms 320L, 320R that mechanically lock the left and right crawlers 350L, 350R, which serve as axes when the tracked vehicle 1 turns, and a locking mechanism control unit 413 that controls the locking mechanisms 320L, 320R. In other words, if the crawler that serves as the pivot axis is left in a freely moving wheel state without a locking mechanism or a speed difference between the left and right crawlers, and the left crawler is left in a freely moving state as the pivot axis when turning left, there is a problem that the left crawler will rotate in response to the rotation of the right crawler, making it difficult to control.However, as described above, by reliably stopping the crawlers 350L and 350R that should be stopped when making a pivot turn and controlling the rotation of the other crawler 350L and 350R, it is possible to minimize positional deviation when the tracked vehicle 1 turns. Therefore, the yield per field area can be maintained or improved.

[0053] The left and right crawlers 350L, 350R of the tracked vehicle 1 according to this embodiment do not have lugs. In other words, by eliminating the lugs on the left and right crawlers 350L and 350R, friction with the soil during turning is reduced, improving sliding and reducing turning torque.

[0054] The turning control device 400 of the tracked vehicle 1 according to this embodiment stops the crawlers that need to be stopped when the tracked vehicle 1 is turning by exciting the driving motors 330L, 330R or mechanically locking them using the locking mechanisms 320L, 320R. In other words, if the crawler that serves as the pivot axis is left in a freely moving wheel state without a locking mechanism or a speed difference between the left and right crawlers, and the left crawler is left in a freely moving state as the pivot axis when turning left, there is a problem that the left crawler will rotate in response to the rotation of the right crawler, making it difficult to control.However, as described above, by reliably stopping the crawlers 350L and 350R that should be stopped when making a pivot turn and controlling the rotation of the other crawler 350L and 350R, it is possible to minimize positional deviation when the tracked vehicle 1 turns. Therefore, the yield per field area can be maintained or improved.

[0055] The turning control unit 411 in the turning control device 400 of the tracked vehicle 1 in this embodiment repeats small-angle turns during pivot turns of the tracked vehicle 1, and for small-angle turns, performs turning control by methods including a method of setting the rotation speed of the driven motors 330L and 330R in advance, a method of measuring the rotation angle using an angular acceleration sensor, a method of detecting the current direction using the first GNSS 150 and the second GNSS 160, and a method of detecting the current direction using the geomagnetic sensor 170. In other words, the turning control unit 411 turns the tracked vehicle 1 to the desired turning angle by repeatedly performing small angle turns using various methods with respect to a set divided turning angle, which is a preset set turning angle that is the original final turning angle divided at a predetermined ratio. This makes it possible to minimize positional deviations when the tracked vehicle 1 turns. Therefore, for example, even if the tracked vehicle 1 is an agricultural robot whose purpose is to harvest crops planted in ridges created in farmland or remove weeds, when it turns between the ridges in a farm field, part of the tracked vehicle 1 will not hit the ridges and cause part of the ridge to collapse, so the ridges can be arranged while ensuring a minimum amount of space for the tracked vehicle 1 as an agricultural robot to run or turn. Therefore, the yield per field area can be maintained or improved.

[0056] <Second embodiment> A tracked vehicle 1A according to this embodiment will be described with reference to FIGS.

[0057] <Configuration of tracked vehicle 1A> As shown in FIG. 5, the tracked vehicle 1 according to this embodiment includes a sensor system group 100, a storage battery 200, a drive system group 300, and a turning control device 400A. The storage battery 200 is a power source that supplies the necessary power to the sensor system group 100, the drive system group 300, and the turning control device 400A. Note that components with the same reference numerals as those in the first embodiment have the same functions, and therefore detailed descriptions thereof will be omitted.

[0058] <Configuration of the turning control device 400A> As shown in FIG. 6, the turning control device 400A includes a processor 410A and a memory 420A. Note that components with the same reference numerals as those in the first embodiment have the same functions, and therefore detailed descriptions thereof will be omitted.

[0059] In this embodiment, the processor 410A controls each part in the turning control device 400A based on information from each sensor constituting the sensor system group 100, and performs autonomous operation of the moving body. In this embodiment, the processor 410A executes obstacle detection processing, turning control, and the like, based on information such as distance image information from the camera 110 and the distance sensor 120, for example.

[0060] The memory 420A is composed of a ROM or RAM, and saves and stores programs and various data. The memory 420A is provided with a storage unit 421A, and the storage unit 421A saves and stores information such as a target turning angle required for the processor 410A to perform turning control and position information for performing turning.

[0061] <Configuration of Processor 410A> As shown in Figure 6, the processor 410A of the turning control device 400A of this embodiment is configured to include a turning control unit 411A, a detection unit 412, an image processing unit 414, a motor control unit 415, and a driving control unit 416. Note that components with the same reference numerals as those in the first embodiment have the same functions, and therefore detailed descriptions thereof will be omitted. As shown in FIG. 6, the turning control unit 411A, the detection unit 412, the image processing unit 414, the motor control unit 415, the traveling control unit 416, and the like are connected via a bus line BL.

[0062] The turning control unit 411A determines the turning axis for gentle turning based on the detection result from the detection unit 412, which will be described later. The turning control unit 411A determines the left and right crawlers 350L, 350R to be rotated and the direction of rotation based on the turning axis information determined for turning control, and executes control for gentle turning. More specifically, the turning control unit 411 alternately changes the axis of the gentle turn and executes control each time the turning angle detected by the detection unit 412 described later becomes a set divided turning angle obtained by dividing a preset set turning angle into a predetermined ratio. Furthermore, the turning control section 411A repeats turning at a small angle during gentle turning. For small angle turns, the turning control unit 411A performs turning control using methods including a method of setting the rotation speed of the driven motors 330L and 330R in advance, a method of measuring the rotation angle using an angular acceleration sensor, a method of detecting the current direction using the first GNSS 150 and the second GNSS 160, and a method of detecting the current direction using the geomagnetic sensor 170.

[0063] <Processing of the turning control device 400A> The turning process of the turning control device 400A according to this embodiment will be described with reference to FIGS. In the following, an example will be described in which the target angle is set to 90 degrees and the tracked vehicle 1A is turned left.

[0064] The turning control unit 411 determines the turning axis for gentle turning (step S210). If the processing has been continued up to this point, the rotation control unit 411 reverses the rotation axis. When the process of step S210 above ends, processor 410A transitions the process to step S220.

[0065] The turning control unit 411A determines the rotation speeds of the left and right crawlers based on the determined turning axis (step S220). For example, when turning left, if the left crawler 350L is used as the turning axis, the rotation speed of the motor 330L of the left crawler 350L is set slower than the rotation speed of the motor 330R of the right crawler 350R. Furthermore, when turning left, if the right crawler 350R is used as the turning axis, the rotation speed of the motor 330R of the right crawler 350R is set slower than the rotation speed of the motor 330L of the left crawler 350L.

[0066] For the purpose of turning control, the turning control unit 411A performs processing to determine the left and right crawlers 350L, 350R to be rotated and the direction of rotation in order to rotate the tracked vehicle 1A around the determined turning axis (step S230). For example, when turning left and using the left crawler 350L as the turning axis, the motor 330R of the right crawler 350R and the motor 330L of the left crawler 350L are rotated in the forward direction. When turning left, the right crawler 350R is used as the turning axis, and the motor 330R of the right crawler 350R and the motor 330L of the left crawler 350L are rotated in the backward direction. For example, when making a right turn, the motor 330R of the right crawler 350R and the motor 330L of the left crawler 350L are rotated in the forward direction with the right crawler 350R as the rotation axis. When turning right, and the left crawler 350L is used as the turning axis, the motor 330R of the right crawler 350R and the motor 330L of the left crawler 350L are rotated in the backward direction. The turning control unit 411A transmits the above information to the traveling control unit 416 via the bus line BL in accordance with the turning direction. The traveling control unit 416 transmits a control signal to the motor control unit 415 based on information from the turning control unit 411A. When the motor control unit 415 receives a control signal from the travel control unit 416, it transmits a drive signal to the motor drivers 310L, 310R that drive the left and right crawlers 350L, 350R, causing the left and right crawlers 350L, 350R to rotate and perform a turning operation. When the process of step S230 above ends, processor 410A transitions the process to step S240.

[0067] The detection unit 412 measures the turning angle based on sensor information obtained from the first GNSS 150 and the second GNSS 160, for example. The turning control unit 411A calculates a set divided turning angle according to the turning angle and the division ratio based on the measurement data in the detection unit 412 (step S240). Here, the turning angle is the cumulative turning angle from the start of turning to the time turning is performed, and the set divided turning angle is the angle turned from the time the turning axis is set until the next turning axis is set. In addition, in this embodiment, the allowable value of the turning angle is the target angle of 90 degrees. When the process of step S240 above ends, processor 410A transitions the process to step S250.

[0068] The turning control unit 411A compares the turning angle with the target angle. If the turning control unit 411A determines that the turning angle is greater than the target angle ("NO" in step S250), it ends all processing. On the other hand, if turning control section 411A determines that the turning angle is equal to or less than the target angle ("YES" in step S250), processor 410A transitions the process to step S260.

[0069] Next, the turning control unit 411A determines whether or not the turning angle has reached a predetermined set divided turning angle (step S260). Then, when it is determined that the turning angle has not reached the predetermined set divided turning angle ("NO" in step S260), the turning control section 411A transitions the process to step S230 to continue the turning process. On the other hand, when it is determined that the turning angle has reached the predetermined set divided turning angle ("YES" in step S260), the turning control section 411A shifts the processing to step S270.

[0070] The turning control unit 411A temporarily suspends the turning operation (step S270), and then transitions the process to step S210. In other words, using Figure 8, which shows the turning behavior of the tracked vehicle 1A when the number of divisions is 3 (a 90-degree turn and the set divided turning angle (target angle) is 30 degrees), the turning control unit 411A changes the direction of the tracked vehicle 1A by 90 degrees from the direction before turning by performing all of the above processing in each step from step 1 (operation from Figure 8(A) to Figure 8(B)) in which the tracked vehicle 1A reaches the first set divided turning angle (first target angle) from its orientation before turning, step 2 (operation from Figure 8(B) to Figure 8(C)) in which the first set divided turning angle (first target angle) reaches the second set divided turning angle (second target angle), and step 3 (operation from Figure 8(C) to Figure 8(D)) in which the second set divided turning angle (second target angle) reaches the third set divided turning angle (third target angle).

[0071] <Actions and Effects> As explained above, the turning control device 400A of the tracked vehicle 1A in this embodiment controls the automatic turning of the tracked vehicle 1 which is equipped with running crawlers 350L, 350R on the left and right, and includes a turning control unit 411A which controls the left and right crawlers 350L, 350R to make gentle turns of the tracked vehicle 1A, and a detection unit 412 which detects the turning angle, and the turning control unit 411A alternately changes the gentle turning axis each time the turning angle detected by the detection unit 412 becomes a set divided turning angle which is a predetermined set turning angle divided by a predetermined ratio, and performs control. In other words, the turning control unit 411A makes the tracked vehicle 1A make gentle turns, and when the turning angle detected by the detection unit 412 becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio, the turning control unit 411A alternately changes the axis of gentle turning and executes control. This makes it possible to minimize positional deviations when the tracked vehicle 1A turns. Therefore, for example, even if the tracked vehicle 1A is an agricultural robot used for purposes such as harvesting crops planted in ridges on farmland or removing weeds, when turning between the ridges in a field, part of the tracked vehicle 1A will not hit the ridges and cause part of the ridge to collapse, so the ridges can be arranged while ensuring a minimum amount of space for the tracked vehicle 1A as an agricultural robot to run or turn. Therefore, the yield per field area can be maintained or improved.

[0072] The left and right crawlers 350L, 350R of the tracked vehicle 1A according to this embodiment do not have lugs. In other words, by eliminating the lugs on the left and right crawlers 350L and 350R, friction with the soil during turning is reduced, improving sliding and reducing turning torque.

[0073] The turning control unit 411A in the turning control device 400A of the tracked vehicle 1A in this embodiment repeats small-angle turns during gentle turns of the tracked vehicle 1A, and for small-angle turns, performs turning control by methods including setting the rotation speed of the driven motors 330L and 330R in advance, measuring the rotation angle using an angular acceleration sensor, detecting the current direction using the first GNSS 150 and the second GNSS 160, and detecting the current direction using a geomagnetic sensor 170. In other words, the turning control unit 411A turns the tracked vehicle 1A to the desired turning angle by repeatedly performing small angle turns using various methods with respect to a set divided turning angle, which is a preset set turning angle that is the original final turning angle divided at a predetermined ratio. This makes it possible to minimize positional deviations when the tracked vehicle 1A turns. Therefore, for example, even if the tracked vehicle 1A is an agricultural robot used for harvesting crops planted in ridges on farmland or removing weeds, when turning between the ridges in a field, part of the tracked vehicle 1 will not hit the ridges and cause part of the ridge to collapse, so the ridges can be arranged while ensuring a minimum amount of space for the tracked vehicle 1A as an agricultural robot to run or turn. Therefore, the yield per field area can be maintained or improved.

[0074] The turning control device 1 of the present invention can be realized by recording the processing of the processor 410 on a recording medium that can be read by a computer system, and having the processor 410 read and execute the program recorded on this recording medium. The computer system here includes hardware such as an OS and peripheral devices.

[0075] Furthermore, if a WWW (World Wide Web) system is used, the "computer system" also includes the homepage providing environment (or display environment). The program may also be transmitted from a computer system in which the program is stored in a storage device or the like to another computer system via a transmission medium or by transmission waves in the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has the function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.

[0076] The program may also be for realizing part of the above-mentioned functions. Furthermore, the above-mentioned functions may be realized in combination with a program already recorded in the computer system, that is, a so-called differential file (differential program).

[0077] The above describes in detail an embodiment of the present invention with reference to the drawings. However, all turning control devices that can be implemented by a person skilled in the art by making appropriate design modifications based on the turning control devices 400, 400A described above as embodiments of the present invention also fall within the technical scope of the present invention as long as they include the gist of the present invention. Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the technical scope of the present invention. For example, any embodiment in which a person skilled in the art has appropriately added or deleted components or modified the design, or added or omitted steps or modified conditions, is included within the technical scope of the present invention as long as it contains the gist of the present invention.

[0078] Furthermore, other effects and advantages brought about by the aspects described in this embodiment that are clear from the description in this specification or that can be appropriately thought of by a person skilled in the art are naturally understood to be brought about by the present invention. Various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be omitted from all the components shown in the embodiment. Furthermore, components from different embodiments may be combined as appropriate. [Explanation of symbols]

[0079] 1; Tracked vehicle 1A; Tracked vehicle 100: Sensor Systems 110;Camera 120;Distance sensor 130;IMU 140: Motor rotation speed measuring device 150;First GNSS 160; Second GNSS 170;Geomagnetic sensor 200; storage battery 300; Drivetrain group 310L, 310R; Motor driver 320L, 320R; locking mechanism 330L, 330R; Motor 340L, 340R; power transmission mechanism 350L, 350R; Crawler 400: Turning control device 400A: Rotation control device 410;processor 410A; Processor 411: Turning control section 411A: Swivel control section 412:Detection unit 413: Lock mechanism control section 414; Image processing unit 415: Motor control unit 416;Travel control unit 420;Memory 420A;Memory 421;Memory part 421A;Storage section

Claims

1. A turning control device that controls automatic turning of a tracked vehicle equipped with crawlers for traveling on the left and right sides, a turning control unit that controls the left and right crawlers to make a pivot turn of the tracked vehicle; a detection unit that detects a turning angle; Including, The turning control unit is a turning control device that alternately changes the axis of the pivot turn and performs control each time the detected turning angle becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio.

2. A turning control device that controls automatic turning of a tracked vehicle equipped with crawlers for traveling on the left and right sides, a turning control unit that controls the left and right crawlers to make gentle turns of the tracked vehicle; a detection unit that detects a turning angle; Including, The turning control unit is a turning control device that alternately changes the axis of the gentle turn and performs control each time the detected turning angle becomes a set divided turning angle obtained by dividing a preset set turning angle by a predetermined ratio.

3. a locking mechanism that mechanically locks the crawler that serves as an axis during rotation; a lock mechanism control unit that controls the lock mechanism; The turning control device of claim 1 , comprising:

4. The turning control device according to any one of claims 1 to 3, wherein the crawler has no lugs.

5. 4. A swing control device according to claim 3, wherein the crawler that should be stopped during swinging is stopped by exciting the driving motor or by mechanically locking it with the locking mechanism.

6. The turning control unit repeats small-angle turns during turning, and for the small-angle turns, performs turning control by a method including a method of setting the rotation speed of the driving motor in advance, a method of measuring the rotation angle using an angular acceleration sensor, a method of detecting the current direction using multiple GNSSs, or a method of detecting the current direction using a geomagnetic sensor. A turning control device as described in claim 4.

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