Swing control device and swing control method

Abstract

To provide a turning method which enables turning with small output without damaging a field as much as possible when a track vehicle is turned.SOLUTION: A turning control device (18) for automatically turning a track vehicle (10) having crawlers (12) for traveling on both ends includes: a turning control part (46) for controlling both of the crawlers until the turning angle of the track vehicle becomes a target turning angle, and ultra-pivotal turning or pivotal turning the track vehicle; and a movement control part (48) for suspending the ultra-pivotal turning or pivotal turning by the turning control part every time the track vehicle is turned by a predetermined division angle, controlling both of the crawlers, and advancing or retracting the track vehicle by a predetermined distance.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a turning control device and a turning control method for automatically turning a track-laying vehicle equipped with crawlers (endless tracks, crawlers, track belts, caterpillars) for traveling left and right.

Background Art

[0002] The track-laying vehicle has crawlers for traveling left and right. The track-laying vehicle can acquire high cross-country performance on rough ground. For example, Patent Document 1 shows a track-laying vehicle using an electric motor as a power source.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the track-laying vehicle makes a sharp turn or a normal turn, the crawlers push the soil in the turning direction. For example, when the track-laying vehicle makes a sharp left turn, soil lumps are formed on the left side of the front half of each crawler and on the right side of the rear half of the crawler. As the turning angle of the track-laying vehicle increases, the soil lumps become larger and the ground becomes rough. Furthermore, when the track-laying vehicle makes a sharp turn while pushing large soil lumps, the power source (such as an electric motor) needs to generate a large torque. Then, the energy consumption of the track-laying vehicle increases. For these reasons, a turning method that can turn with as little damage to the field as possible and with a small output when the track-laying vehicle turns is desired.

[0005] An object of the present invention is to solve the above-described problems.

Means for Solving the Problems

[0006] A first aspect of the present invention is a turning control device for automatically turning a track-laying vehicle equipped with crawlers for traveling left and right. The turning control device includes a turning control unit that controls the left and right crawlers until the turning angle of the track-laying vehicle reaches a target turning angle, so as to turn the track-laying vehicle in a skid steering or a coordinated turning manner, and a movement control unit that temporarily interrupts the skid steering or the coordinated turning by the turning control unit each time the track-laying vehicle turns by a predetermined division angle, and controls the left and right crawlers to move the track-laying vehicle forward or backward by a predetermined distance.

[0007] A second aspect of the present invention is a turning control method for performing automatic turning control of a track-laying vehicle equipped with crawlers for traveling left and right by using a computer. The turning control method includes a turning step of controlling the left and right crawlers until the turning angle of the track-laying vehicle reaches a target turning angle, so as to turn the track-laying vehicle in a skid steering or a coordinated turning manner, and a movement step of temporarily interrupting the skid steering or the coordinated turning in the turning step each time the track-laying vehicle turns by a predetermined division angle, and controlling the left and right crawlers to move the track-laying vehicle forward or backward by a predetermined distance.

Advantages of the Invention

[0008] According to the present invention, the roughness of the ground can be reduced, and the energy consumption can be decreased.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0010] [Configuration of Rail-Laying Vehicle 10] FIG. 1 is a block diagram showing a rail-laying vehicle 10. The rail-laying vehicle 10 is provided with crawlers 12R and 12L on the left and right sides of the vehicle body. The rail-laying vehicle 10 can move forward, backward, and turn by driving the left and right crawlers 12R and 12L. The rail-laying vehicle 10 of the present embodiment is a vehicle that automatically performs turning control. For example, the rail-laying vehicle 10 is an autonomous vehicle that automatically performs traveling control and turning control.

[0011] The rail-laying vehicle 10 of the present embodiment has electric motors (traveling motors 50R and 50L) as power sources, but may have an engine, a hydraulic motor, or the like as a power source. Also, the rail-laying vehicle 10 of the present embodiment has a pair of electric motors corresponding individually to the left and right crawlers 12R and 12L, but may have one electric motor. The output of one electric motor is distributed and supplied to the left and right crawlers 12R and 12L. In the present embodiment, the rail-laying vehicle 10 is assumed to be a small transporter that follows and moves forward a preceding following target (for example, a person). The small transporter transports, for example, agricultural products harvested by a person in a field.

[0012] The rail-laying vehicle 10 has an input device group 16, a traveling control device 18, a battery 20, two motor control circuits 22R and 22L, and left and right drive devices 24R and 24L. The input device group 16 includes one or more cameras 26 and an inertial measurement device 28. The one or more cameras 26 are sensors that acquire information such as the position of the following target. As a sensor for acquiring information on the following target, LiDAR may be used. Also, in order to automatically follow the rail-laying vehicle 10 to the following target, another following system using a beacon or the like may be used. Also, instead of the inertial measurement device 28, an attitude and azimuth reference device may be used. The drive device 24R includes a traveling motor 50R, a power transmission mechanism 52R, and a crawler 12R. The drive device 24L includes a traveling motor 50L, a power transmission mechanism 52L, and a crawler 12L. The traveling motors 50R and 50L are power sources of the rail-laying vehicle 10.

[0013] Hereinafter, the motor control circuits 22R and 22L are also simply referred to as the motor control circuit 22. Also, the traveling motors 50R and 50L are also simply referred to as the traveling motor 50. Also, the power transmission mechanisms 52R and 52L are also simply referred to as the power transmission mechanism 52. Also, the crawlers 12R and 12L are also simply referred to as the crawler 12.

[0014] The camera 26 images the periphery of the track-laying vehicle 10. At least one camera 26 images the front of the track-laying vehicle 10. The camera 26 outputs the image data acquired by imaging to the travel control device 18. The inertial measurement device 28 has a three-axis gyro and a three-direction acceleration sensor. The inertial measurement device 28 measures the acceleration and turning angular velocity of the track-laying vehicle 10. The inertial measurement device 28 outputs the measurement data to the travel control device 18.

[0015] The travel control device 18 performs control related to the travel (forward, backward, turning, etc.) of the track-laying vehicle 10. That is, the travel control device 18 functions as a turning control device. The travel control device 18 has an arithmetic device 32 and a storage device 34.

[0016] The arithmetic device 32 is a computer and has a processing circuit. The processing circuit may be a processor such as a CPU. The processing circuit may be an integrated circuit such as an ASIC or FPGA. The processor can execute various processes by executing a program stored in the storage device 34. The arithmetic device 32 functions as an acquisition unit 36, a target recognition unit 38, a position recognition unit 40, a motion determination unit 42, a travel control unit 44, a turning control unit 46, and a movement control unit 48. At least a part of the plurality of processes may be executed by an electronic circuit including a discrete device.

[0017] The acquisition unit 36 acquires various data (image data of the camera 26, measurement data of the inertial measurement unit 28, etc.) from the input device group 16. The target recognition unit 38 performs image recognition using the image data and recognizes the tracking target (person). The position recognition unit 40 recognizes each of the position of the rail mounting vehicle 10 in the field and the orientation of the rail mounting vehicle 10 based on the measurement data. The operation determination unit 42 determines the operation of the rail mounting vehicle 10, such as the traveling direction (moving direction), traveling speed, necessity of turning, angle to be turned, etc., based on the recognition result of the target recognition unit 38 and the recognition result of the position recognition unit 40. The traveling control unit 44 performs traveling control of the rail mounting vehicle 10 based on the determination result of the operation determination unit 42. The turning control unit 46 performs turning control of the rail mounting vehicle 10 based on the determination result of the operation determination unit 42. The movement control unit 48 performs movement control of the rail mounting vehicle 10 based on the determination result of the operation determination unit 42.

[0018] The storage device 34 has a volatile memory and a non-volatile memory. Examples of the volatile memory include RAM and the like. The volatile memory is used as the working memory of the processor. The volatile memory temporarily stores data necessary for processing or calculation. Examples of the non-volatile memory include ROM, flash memory, and the like. The non-volatile memory is used as a storage memory. The non-volatile memory stores programs, tables, maps, etc. At least a part of the storage device 34 may be provided in the above-described processor, integrated circuit, etc.

[0019] The memory device 34 stores various predetermined values used in various controls. For example, the memory device 34 stores, as predetermined values, a divided angle as a predetermined angle for turning the rail-mounted vehicle 10 around one turning center position, and a predetermined distance for the rail-mounted vehicle 10 to move back and forth during turning. As the divided angle, for example, a calculated value of an operation of (the length of the turning arc corresponding to the width D of the crawler 12) / (the turning radius of the ultra-short turning) is preset. This divided angle is a turning angle for moving the front end and the rear end of the crawler 12 in the turning direction by an amount corresponding to the width D of the crawler 12. More specifically, this divided angle is the angle of turning until the right front end of the crawler 12L reaches the position of the left side surface of the crawler 12L before turning when the rail-mounted vehicle 10 turns left. Also, this divided angle is the angle of turning until the left front end of the crawler 12R reaches the position of the right side surface of the crawler 12R before turning when the rail-mounted vehicle 10 turns right.

[0020] The motor control circuit 22 includes an inverter circuit or the like. The switching element of the inverter circuit switches according to the control signal output by the arithmetic unit 32. The motor control circuit 22 converts the direct current of the battery 20 into an alternating current and outputs it to the traveling motor 50.

[0021] The traveling motor 50 is an electric motor, for example, a three-phase alternating current motor. The traveling motor 50 is driven by the electric power supplied from the battery 20 via the motor control circuit 22. The output shaft of the traveling motor 50 is connected to a drive wheel (not shown) via a power transmission mechanism 52. The power transmission mechanism 52 includes, for example, a speed reducer or the like. The drive wheel rotates the crawler 12.

[0022] [2 Turning Control and Movement Control] FIG. 2 is a flowchart showing the flow of control performed by the arithmetic unit 32 provided in the travel control device 18. When the track-laying vehicle 10 travels following a target to be followed, the operation determination unit 42 determines the rotation direction and rotation speed of each travel motor 50 so that the direction of the track-laying vehicle 10 coincides with the direction of the target to be followed. When the angular difference between the direction of the track-laying vehicle 10 and the direction of the target to be followed is equal to or greater than a predetermined value, the operation determination unit 42 determines that turning is necessary. In this specification, this angular difference is referred to as the angle to be turned, that is, the target angle of turning. The operation determination unit 42 calculates the target angle and stores it in the storage device 34. The storage device 34 stores the target angle until the turning is completed. When the track-laying vehicle 10 turns, the travel control device 18 performs the processing shown in FIG. 2.

[0023] In step S1, the turning control unit 46 performs turning control. Here, the turning control unit 46 performs super-creeping turning control as the turning control. Note that the turning control unit 46 may perform creeping turning control as the turning control. The turning control unit 46 performs super-creeping turning by rotating each of the travel motor 50R and the travel motor 50L in opposite directions to each other. When performing super-creeping turning, the turning control unit 46 may make the rotation speed of the travel motor 50R equal to the rotation speed of the travel motor 50L, or may make them different from each other. When step S1 ends, the process proceeds to step S2.

[0024] In step S2, the acquisition unit 36 acquires the measurement data of the inertial measurement device 28. The position recognition unit 40 calculates a first turning angle and a second turning angle based on the measurement data. The first turning angle is the angle by which the track-laying vehicle 10 has continuously turned at the same position. The maximum allowable value of the first turning angle is the divided angle. On the other hand, the second turning angle is the angle by which the track-laying vehicle 10 has turned from the start of turning to the latest turning angle calculation time point. The maximum allowable value of the second turning angle is the target angle. When step S2 ends, the process proceeds to step S3.

[0025] In step S3, the turning control unit 46 compares the second turning angle with the target angle. If the second turning angle is less than the target angle (step S3: YES), the process proceeds to step S4. At this stage, the turning has not ended. Therefore, the turning control unit 46 continues the turning control. On the other hand, if the second turning angle is greater than or equal to the target angle (step S3: NO), the series of processes shown in FIG. 2 ends. At this stage, the track-laying vehicle 10 is facing the target to be followed.

[0026] When the process proceeds from step S3 to step S4, the turning control unit 46 compares the first turning angle with the divided angle. If the first turning angle is greater than or equal to the divided angle (step S4: YES), the process proceeds to step S5. At this stage, the turning up to the divided angle has ended. On the other hand, if the first turning angle is less than the divided angle (step S4: NO), the process returns to step S1. At this stage, the turning up to the divided angle and the turning up to the target angle have not ended. Therefore, the turning control unit 46 continues the turning control.

[0027] When the process proceeds from step S4 to step S5, the movement control unit 48 temporarily interrupts the turning control performed by the turning control unit 46. When step S5 ends, the process proceeds to step S6.

[0028] In step S6, the movement control unit 48 moves the track-laying vehicle 10 forward or backward by a predetermined distance by rotating each traveling motor 50 in the same direction by a predetermined amount. After rotating the traveling motor 50 in the same direction by a predetermined amount, the movement control unit 48 releases the interruption of the turning control. When step S6 ends, the process proceeds to step S7.

[0029] In step S7, the position recognition unit 40 resets the first turning angle. When step S7 ends, the process returns to step S1.

[0030] [3 Operations of the Track-Laying Vehicle 10] [3-1 First Example] FIG. 3 is an operation explanatory diagram showing a first example of the turning operation of the track-laying vehicle 10 in time series. The first example is a control example in which the movement control unit 48 advances the track-laying vehicle 10 in the movement control (step S6 in FIG. 2).

[0031] At time points t0 to t1, the turning control unit 46 turns the track-laying vehicle 10 at an ultra-high speed to the left (arrow A) (step S1 in FIG. 2). During the turning of the track-laying vehicle 10, soil masses 56 are formed on the left side of the front half of the crawler 12 and on the right side of the rear half of the crawler 12. In FIG. 3, the dotted area is the soil mass 56.

[0032] At time point t1, the turning control unit 46 determines that the first turning angle has reached the divided angle (step S4 in FIG. 2: YES). The turning control unit 46 temporarily interrupts the turning control (step S5 in FIG. 2).

[0033] At time points t1 to t2, the movement control unit 48 moves the track-laying vehicle 10 forward by a predetermined distance (arrow B) (step S6 in FIG. 2). When the track-laying vehicle 10 advances by half of the crawler length L or more, the front half of the crawler 12 can move to a position where there is no soil mass 56 on the left side, and the rear half of the crawler 12 can move to a position where there is no soil mass 56 on the right side. On the other hand, if the movement distance of the track-laying vehicle 10 is too long, the positional deviation of the turning center of the track-laying vehicle 10 will increase before the turning angle of the track-laying vehicle 10 reaches the target angle. In order to reduce the positional deviation of the turning center, it is preferable that the predetermined distance is as small as possible. From the above, the predetermined distance that the track-laying vehicle 10 moves at the time of one turning interruption is preferably a length of half of the crawler length L or more and the crawler length L or less. Furthermore, the predetermined distance is preferably half of the crawler length L, i.e., L / 2. Note that the crawler length L is the length from the front end of the crawler 12 to the rear end of the crawler 12.

[0034] After time point t2 (time points t2, t3, etc.), the turning control unit 46 performs the same control as the control from time point t0 to time point t2 until the second turning angle reaches the target angle. When the second turning angle reaches the target angle, the turning control unit 46 ends the turning control. At this time, the track-laying vehicle 10 is facing the target to be followed. The traveling control unit 44 controls each traveling motor 50 so that the track-laying vehicle 10 travels following the target to be followed.

[0035] As described above, in the first example, when the traveling control device 18 (turning control device) turns the track-laying vehicle 10 by the target angle, it alternately performs turning control and movement control. In other words, the track-laying vehicle 10 turns by the target angle while moving the turning position (turning center position). The size of each soil mass 56 formed by the first example is smaller than the size of the soil mass 56 formed by turning by the target angle at one location. Therefore, the traveling control device 18 can reduce the size of the soil mass 56 formed when the track-laying vehicle 10 turns. As a result, the torque required for the traveling motor 50 when the track-laying vehicle 10 turns is reduced. That is, by performing the operation of the first example, the traveling control device 18 can reduce the roughness of the ground and also reduce the power consumption.

[0036] [3-2 Second Example] FIG. 4 is an operation explanatory diagram showing a second example of the turning operation of the track-laying vehicle 10 in time series. The second example is a control example in which the movement control unit 48 alternately performs movement control to move the track-laying vehicle 10 forward and movement control to move the track-laying vehicle 10 backward.

[0037] The operations from time point t0 to time point t3 in the second example are the same as those from time point t0 to time point t3 in the first example. The first example and the second example differ in the moving direction of the rail-mounted vehicle 10 from time point t3 to time point t4, that is, the moving direction of the second moving control. In the first example, after time point t3, the movement control unit 48 moves the rail-mounted vehicle 10 forward (arrow B) by a predetermined distance (half of the crawler length L, i.e., L / 2). On the other hand, in the second example, from time point t3 to time point t4, the movement control unit 48 moves the rail-mounted vehicle 10 backward (arrow C) by a predetermined distance (half of the crawler length L, i.e., L / 2).

[0038] Thus, in the second example, the movement control unit 48 moves the rail-mounted vehicle 10 forward in the odd-numbered movement control (step S6 in FIG. 2) and moves the rail-mounted vehicle 10 backward in the even-numbered movement control (step S6 in FIG. 2). Note that the movement control unit 48 may move the rail-mounted vehicle 10 backward in the odd-numbered movement control and move the rail-mounted vehicle 10 forward in the even-numbered movement control. In short, the movement control unit 48 makes the moving direction of the rail-mounted vehicle 10 at the nth (n is a natural number of 2 or more) turning interruption opposite to the moving direction of the rail-mounted vehicle 10 at the (n - 1)th turning interruption.

[0039] Note that the movement control unit 48 may perform forward and backward movements in a preset order.

[0040] By performing the operation of the second example, the traveling control device 18 can not only achieve the same effect as the first example, but also further reduce the displacement of the turning center. Further, by alternately switching the moving direction of the rail-laying vehicle 10, the rail-laying vehicle 10 moves on a part of the soil mass 56 formed immediately before the nth movement. Then, the soil mass 56 is compacted. That is, by performing the operation of the second example, the traveling control device 18 can further reduce the roughness of the ground compared to the first example. Further, the traveling control device 18 can turn the rail-laying vehicle 10 by an angle corresponding to the width D of the crawler 12 and move it back and forth in the direction opposite to the back-and-forth movement direction after the previous turn. Thereby, the rail-laying vehicle 10 can move so as not to overlap the place where the crawler 12 has already compacted. Thus, the traveling control device 18 can efficiently reduce the roughness of the ground.

[0041] [4 Other Embodiments] The rail-laying vehicle 10 of the above-described embodiment moves forward following the target (person) to be followed. However, the rail-laying vehicle 10 may move forward along a preset traveling route. In this case, the target recognition unit 38 recognizes the traveling route. The operation determination unit 42 determines the direction in which the rail-laying vehicle 10 should travel, the angle by which the rail-laying vehicle 10 should turn, etc., based on the traveling route recognized by the target recognition unit 38 and the position and orientation of the rail-laying vehicle 10 recognized by the position recognition unit 40.

[0042] Alternatively, the rail-laying vehicle 10 may be a manned vehicle in which the user performs control other than turning control and only the turning control is automatically performed. Further, the rail-laying vehicle 10 may be a remotely operated vehicle that is operated by the user from a remote location. When the rail-laying vehicle 10 is a manned vehicle or a remotely operated vehicle, for example, when the user gives an instruction to turn (button operation, etc.), the turning control unit 46 and the movement control unit 48 perform the automatic control shown in FIG. 2.

[0043] When calculating the turning angle of the tracked vehicle 10, the position recognition unit 40 does not necessarily use the measurement data of the inertial measurement device 28. For example, the position recognition unit 40 can also calculate the turning angle of the tracked vehicle 10 based on the turning time, the load of the power source (the current value of the traveling motor 50 in the above embodiment), and the like.

[0044] The divided angle may be variable. For example, the operation determination unit 42 may calculate the divided angle by dividing the target angle into a predetermined equal division.

[0045] The divided angle may be set according to the state of the soil at the location where the tracked vehicle 10 performs work. For example, in soft soil, a small divided angle is set. Also, in hard soil, it is possible to set a large divided angle.

[0046] [Invention Obtained from the 5th Embodiment] The invention that can be grasped from the above embodiment will be described below.

[0047] The first aspect of the present invention is a turning control device (18) that performs automatic turning of a tracked vehicle (10) equipped with crawlers (12) for traveling on the left and right, comprising: a turning control unit (46) that controls the left and right crawlers until the turning angle of the tracked vehicle reaches a target turning angle, and turns the tracked vehicle in a super accurate manner or a reliable manner; and a movement control unit (48) that temporarily interrupts the super accurate turning or reliable turning by the turning control unit each time the tracked vehicle turns by a predetermined divided angle, and controls the left and right crawlers to move the tracked vehicle forward or backward by a predetermined distance.

[0048] In the first aspect, the movement control unit may move the tracked vehicle forward or backward by a distance equal to half or more of the crawler length (L), which is the length from the front end to the rear end of the crawler, and equal to or less than the crawler length.

[0049] In the first aspect, the movement control unit may move the tracked vehicle forward or backward by a distance equal to half of the crawler length.

[0050] In the first aspect, the movement control unit may set the moving direction of the track-laying vehicle at the nth (n is a natural number of 2 or more) turning interruption to be opposite to the moving direction of the track-laying vehicle at the (n - 1)th turning interruption.

[0051] In the first aspect, the power source of the track-laying vehicle may be an electric motor (50).

[0052] In the first aspect, when the turning control unit causes the track-laying vehicle to perform a super-accurate turn, the divided angle may be set to (the length of the turning arc corresponding to the width (D) of the crawler) / (the turning radius of the super-accurate turn).

[0053] In the first aspect, the divided angle may be set according to the state of the soil at the location where the track-laying vehicle performs work.

[0054] A second aspect of the present invention is a turning control method for automatically controlling the turning of a track-laying vehicle equipped with crawlers for traveling left and right, using a computer, the method including: a turning step of controlling the left and right crawlers until the turning angle of the track-laying vehicle reaches a target turning angle, to cause the track-laying vehicle to perform a super-accurate turn or an accurate turn; and a movement step of temporarily interrupting the super-accurate turn or the accurate turn in the turning step each time the track-laying vehicle turns by a predetermined divided angle, and controlling the left and right crawlers to move the track-laying vehicle forward or backward by a predetermined distance.

Explanation of Reference Numerals

[0055] 10... Track-laying vehicle 12... Crawler 18... Travel control device (turning control device) 46... Turning control unit 48... Movement control unit 50... Travel motor (electric motor)

Claims

1. A turning control device for automatically turning a track-laying vehicle equipped with crawlers for traveling left and right, a turning control unit that controls the left and right crawlers until the turning angle of the track-laying vehicle reaches a target turning angle, and turns the track-laying vehicle in a super-aggressive turn or a normal turn; A turning control device comprising: a movement control unit that temporarily interrupts the super-aggressive turn or the normal turn by the turning control unit every time the track-laying vehicle turns by a predetermined division angle, and controls the left and right crawlers to move the track-laying vehicle forward or backward by a predetermined distance.

2. The turning control device according to claim 1, wherein the movement control unit moves the track-laying vehicle forward or backward by a distance equal to at least half of the crawler length, which is the length from the front end to the rear end of the crawler, and not more than the crawler length.

3. The turning control device according to claim 2, wherein the movement control unit moves the track-laying vehicle forward or backward by a distance equal to half of the crawler length.

4. The turning control device according to any one of claims 1 to 3, wherein the movement control unit sets the moving direction of the track-laying vehicle at the nth (n is a natural number of 2 or more) turning interruption to be opposite to the moving direction of the track-laying vehicle at the (n - 1)th turning interruption.

5. The turning control device according to any one of claims 1 to 4, wherein the power source of the track-laying vehicle is an electric motor.

6. The turning control device according to any one of claims 1 to 5, wherein when the turning control unit turns the track-laying vehicle in a super-aggressive turn, the division angle is set to (the length of the turning arc corresponding to the width of the crawler) / (the turning radius of the super-aggressive turn).

7. The turning control device according to any one of claims 1 to 5, wherein the division angle is set according to the state of the soil at the location where the track-laying vehicle performs work.

8. A turning control method for automatically controlling the turning of a track-laying vehicle equipped with crawlers for traveling left and right, using a computer, a turning step of controlling the left and right crawlers until the turning angle of the track-laying vehicle reaches a target turning angle, and turning the track-laying vehicle in a super-aggressive turn or a normal turn; A turning control method that, each time the tracked vehicle turns by a predetermined division angle, temporarily interrupts the over-center turning or on-center turning in the turning process, controls the left and right crawlers, and performs a moving process of moving the tracked vehicle forward or backward by a predetermined distance.

Images