JP5918162B2 - Traveling vehicle - Google Patents

Description

  The present invention relates to a technique for smoothly switching between an automatic travel mode and a manual travel mode in a traveling vehicle that enables automatic traveling.

2. Description of the Related Art Conventionally, as an example of a traveling vehicle, a tractor that includes an automatic steering control unit and a GPS position information calculation unit in a tractor and that automatically operates along a set route to enable work (for example, a patent) Reference 1).
In order to automatically run the tractor, an autonomous running means is provided so as to autonomously run on a predetermined route in the field.

JP 2002-186309 A

  When the tractor is manually moved to the start position in the field and the automatic travel changeover switch or the like is operated to start automatic travel, for example, when the steering device stops at an angle other than the straight traveling direction and starts automatic travel, In some cases, the steering device was cut in a straight direction and the vehicle turned sharply. Even if the main speed change lever or the forward / reverse switching lever is stopped at the neutral position, if the sub speed change lever is at the high speed position and the automatic travel start operation is performed, the sub speed change is performed at the work speed simultaneously with the PTO drive. Since the speed is switched to a certain low speed, the traveling speed suddenly changes, which not only gives a shock to the worker, but also makes the field at the work start position rough.

  The present invention has been made in view of the above situation, and provides a traveling vehicle that prevents a traveling speed and a traveling direction from changing suddenly when switching from a manual traveling mode to an automatic traveling mode.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a GPS position calculating means for receiving a radio wave transmitted from a GPS satellite and calculating a position of the airframe, a steering driving means for rotating a steering device, an engine rotation control means, and a speed changing means. And an automatic running that enables automatic running by controlling the steering drive means, the engine rotation control means, and the speed change means so as to run along the set route based on the position of the airframe. In a traveling vehicle having a mode and a manual travel mode that enables the vehicle to travel in response to an artificial operation of the speed change operation means, the steering operation means, and the engine rotation operation means, the control unit includes an automatic travel mode and a manual travel mode. The mode switching operation means for switching the mode is connected, and when the mode switching operation means is switched from manual to automatic, the control unit controls the vehicle speed to be equal to or lower than the set speed. The device is in a substantially straight running position, the forward / reverse switching means is neutral, the clutch is turned off, the brake is turned off, the auxiliary transmission is in a low speed position, the running vehicle is normal, and the engine speed When the rotation speed is equal to or higher than the set rotational speed, the mode is switched to the automatic travel preparation mode, and the automatic travel mode is started when the necessary data for the automatic travel are obtained.

  According to a second aspect of the present invention, in the automatic travel preparation mode, the control unit is configured such that the vehicle speed is faster than the set speed, the steering operation means is not in a substantially straight position, or a set time from the switching operation by the mode switching operation means. When the time has elapsed, the mode shifts to the manual travel preparation mode.

  According to a third aspect of the present invention, when the automatic travel preparation mode is entered, the control unit changes the engine to idle rotation and performs travel stop control.

  By using the means as described above, the automatic travel preparation mode is switched in the middle of switching from the manual travel mode to the automatic travel mode, and there is no sudden start or sudden turn. Even if this occurs, it is possible to confirm and cancel the transition to automatic driving, and to smoothly switch from manual driving mode to automatic driving mode.

The schematic side view which shows a tractor, a GPS satellite, and a reference station. The top view of a tractor. Control block diagram. The figure which shows the mode transition conditions.

  First, the overall configuration of the tractor 1 will be described as an example of a traveling vehicle. However, the traveling vehicle is not limited to a tractor, and may be a rice transplanter, a riding management machine, a transport vehicle, or the like that has a plurality of traveling wheels and can be traveled and can be steered by a steering device.

  1 to 3, an engine 3 is installed in the hood 2, a dashboard 14 is provided in a cabin 11 at the rear of the hood 2, and a steering handle 4 serving as a steering operation means is provided on the dashboard 14. It has been. By turning the steering handle 4, the direction of the front wheels 9, 9 is turned through the steering device, and the turning angle is detected by a rudder angle sensor 7a provided at the turning base of the front wheel 9, and the rudder angle sensor 7a. The detection value obtained by the above is input to the control unit 30. A driver seat 5 is disposed behind the steering handle 4, and a mission case 6 is disposed below the driver seat 5. Rear axle cases 8 and 8 are connected to the left and right sides of the transmission case 6, and rear wheels 10 and 10 are supported on the rear axle cases 8 and 8 via axles. The power from the engine 3 is shifted by a main transmission and an auxiliary transmission in the mission case 6 so that the rear wheels 10 and 10 can be driven. The rotational speed of the rear wheel 10 is detected by the vehicle speed sensor 27 and input to the control unit 30 as the traveling speed. However, the vehicle speed detection method and the arrangement position are not limited.

  A front axle case 7 is supported on a front frame 13 that supports the engine 3, front wheels 9 and 9 are supported on both sides of the front axle case 7, and power from the transmission case 6 can be transmitted to the front wheels 9 and 9. It is configured. The front wheels 9, 9 are steered wheels, and can be turned by turning the steering handle 4, and the front wheels 9, 9 can be turned left and right by a steering actuator 40 comprising a power steering cylinder as a steering drive means. It is possible. The steering actuator 40 is connected to the control unit 30 and is driven by automatic traveling control.

  A step 12 is formed below the driver seat 5 and the steering handle 4. The left and right brake pedals 15 and 15 and the accelerator pedal 28 are arranged at the lower right of the dashboard 14 in the traveling direction on the step 12, the parking lever 39 is arranged in the vicinity thereof, and the clutch pedal 16 is arranged at the lower left of the dashboard 14. Is done. The depression amount of the brake pedal 15 is detected by the brake sensor 15a, the operation of the parking lever 39 is detected by the parking lever position sensor 39a, the brake sensor 15a and the parking lever position sensor 39a are connected to the control unit 30, and the brake sensor 15a The brake actuator 41 serving as a braking means is actuated in accordance with the detection value of the parking lever position sensor 39a, and braking is possible by the brake provided in the rear axle case 8 (or the transmission case 6).

  The clutch pedal 16 is used to turn on and off a clutch provided between the engine 3 and the differential device. A clutch sensor 16a is provided at the rotation base of the clutch pedal 16, and the clutch is connected / disconnected by the operation of the clutch actuator 46. The clutch sensor 16a and the clutch actuator 46 are connected to the control unit 30. When the clutch pedal 16 is depressed, it is detected by the clutch sensor 16a, and the clutch actuator 46 is actuated via the control unit 30 to disengage (turn off) the clutch. Depending on the work vehicle, the clutch may be disposed between the engine 3 and the transmission, may be disposed on the transmission, or may be disposed on the forward / reverse switching device, and the arrangement position of the clutch is limited. is not. Further, the configuration of the clutch is not limited to a friction type or a hydraulic type.

  Further, an accelerator lever 21 and a work machine up / down switch are disposed on the right side of the dashboard 14, and a forward / reverse switching lever 22 is disposed on the left side of the dashboard 14. The operation amounts of the accelerator lever 21 and the accelerator pedal 28 are detected by an accelerator sensor 21a, and the accelerator sensor 21a is connected to the control unit 30 and inputs a detection value. The controller 30 is connected to an engine controller 60 and an engine speed sensor 61 serving as engine speed control means. The engine controller 60 is connected to an accelerator actuator 42 that changes the speed. The accelerator actuator 42 is operated so that the rotation of the engine 3 becomes the rotation speed set by the accelerator lever 21 or the accelerator pedal 28 or the automatic travel setting means 70. The accelerator actuator 42 includes a throttle change motor, a rack actuator that changes the fuel injection amount, a solenoid that opens and closes the fuel injection nozzle, and the like according to the type of engine.

  A switching position detection sensor 22 a is disposed at the rotation base of the forward / reverse switching lever 22 to detect the switching position, and a forward / reverse switching device is disposed in the mission case 6 so as to be switched by the forward / reverse switching actuator 43. . The switching position detection sensor 22a and the forward / reverse switching actuator 43 are connected to the controller 30, and when the forward / reverse switching lever 22 is operated, the forward / reverse switching actuator 43 is operated to perform forward / reverse switching. The configuration for switching between forward and backward movement is possible by a gear sliding type, a hydraulic clutch type, an HST swash plate changing type, etc., and is not limited. The forward / backward switching actuator 43 is a motor, solenoid or the like. It can be configured and is not limited.

  On the dashboard 14, there are arranged display means 49 for displaying the engine speed, abnormality, set value and the like, an automatic / manual changeover switch 71 serving as a key switch and mode changeover operation means, and the like. The automatic / manual changeover switch 71 switches between the automatic running mode and the manual running mode by human operation, and will be described in detail later. Further, the arrangement positions of the display means 49 and the automatic / manual changeover switch 71 are not limited, and may be provided on a column of the cabin 11 or the like.

  On the right side of the driver's seat 5, a main transmission lever 17, an elevating lever 18 for adjusting the height of the work implement, a PTO on / off switch 25, and the like are disposed. 17a is provided to detect the rotation operation position, and the main shift lever position sensor 17a is connected to the control unit 30 to input a detection value. The transmission case 6 is provided with a main transmission actuator 44 for shifting the main transmission, and is operated in accordance with the operation of the main transmission lever 17 to change the speed. In the present embodiment, the main transmission is constituted by a hydraulic continuously variable transmission, and the swash plate is tilted by a main transmission actuator 44 constituted by a solenoid, a motor, or the like to change gears.

A lift lever position sensor 18a is disposed at the rotation base of the lift lever 18 to detect the rotation operation position, and the lift lever position sensor 18a is connected to the control unit 30 to receive a detection value. When the elevating lever 18 is operated, the elevating actuator 48 described later is switched, and the elevating hydraulic cylinder 26 is operated to elevate the rotary tiller 24.
The PTO on / off switch 25 is used to connect / disconnect the PTO clutch provided in the mission case 6. The PTO on / off switch 25 and the PTO clutch actuator 45 for switching the PTO clutch are connected to the control unit 30, By operating the switch 25, the PTO clutch actuator 45 is actuated, and the power can be connected to the PTO shaft.

On the left side of the driver seat 5, a PTO speed change lever 19, a sub speed change lever 20, and the like are arranged. A sub-transmission lever position sensor 20a is provided at the rotation base of the sub-transmission lever 20, and the sub-transmission lever position sensor 20a is connected to the control unit 30 and receives a detection value. The transmission case 6 is provided with a sub-transmission actuator 47 for shifting the sub-transmission device, and is actuated according to the operation of the sub-transmission lever 20 to change the speed. The main transmission lever 17 and the sub transmission lever 20 are used as transmission operation means, and the main transmission actuator 44 and the sub transmission actuator 47 are used as transmission means.
The driver's seat 5, the steering handle 4, the main transmission lever 17, the auxiliary transmission lever 20, and the like are covered with the cabin 11. In addition, the arrangement positions of the levers and the switches are not limited.

  Further, a rotary tiller 24 is installed as a work machine behind the tractor body via a work machine mounting device 23 so as to be able to move up and down to perform the tilling work. An elevating cylinder 26 is provided on the transmission case 6, and the elevating arm 26 constituting the work implement mounting device 23 is rotated by moving the elevating cylinder 26 to extend and lower the rotary tiller 24. In addition, a tilting cylinder is provided on one side of the work implement mounting device 23 so that the rotary tiller 24 can be tilted left and right.

  A mobile GPS antenna 34 that receives radio waves from a GPS satellite 37 is provided on the cabin 11, the mobile GPS antenna 34 is connected to a mobile receiver 33, and the mobile receiver 33 is connected to the control unit 30. The control unit 30 includes GPS position calculating means and displacement / orientation calculating means as means for detecting the traveling state of the tractor 1, and is connected to the gyro sensor 31, the direction sensor 32, and the mobile receiver 33. .

Next, a method for acquiring the traveling state of the tractor 1 will be described.
The tractor 1 includes a gyro sensor 31 and an orientation sensor 32 in order to obtain attitude information of the aircraft.
The gyro sensor 31 detects the angular velocity of the tractor 1 in the longitudinal direction (pitch), the angular velocity in the lateral direction (roll), and the angular velocity of turning (yaw). By integrating and calculating the three angular velocities, it is possible to obtain the inclination angle and the turning angle of the airframe of the tractor 1 in the front-rear direction and the left-right direction. Specific examples of the gyro sensor 31 include a mechanical gyro sensor, an optical gyro sensor, a fluid gyro sensor, and a vibration gyro sensor. The gyro sensor 31 is connected to the control unit 30 and inputs information related to the three angular velocities to the control unit 30.

  The direction sensor 32 detects the direction (traveling direction) of the tractor 1. A specific example of the direction sensor 32 includes a magnetic direction sensor. The direction sensor 32 is connected to the control unit 30 and inputs information related to the orientation of the aircraft to the control unit 30.

  In this way, the control unit 30 calculates the signals acquired from the gyro sensor 31 and the azimuth sensor 32 by the displacement / azimuth calculation means, and obtains the attitude of the tractor 1 (direction, forward / backward direction of the body, left / right inclination of the body, and turning direction). .

Next, a method for acquiring the position information of the tractor 1 using the GPS (global positioning system) will be described.
GPS was originally developed as a navigation support system for aircraft, ships, etc., and is composed of 24 GPS satellites (four on six orbital planes) orbiting about 20,000 kilometers above the sky. It consists of a control station that performs tracking and control, and a user receiver that performs positioning.
As a positioning method using GPS, there are various methods such as single positioning, relative positioning, DGPS (differential GPS) positioning, RTK-GPS (real-time kinematics-GPS) positioning, and any of these methods can be used. However, in the present embodiment, an RTK-GPS positioning method with high measurement accuracy is adopted, and this method will be described with reference to FIGS.

  RTK-GPS (real-time kinematics-GPS) positioning is performed by simultaneously performing GPS observations on a reference station whose position is known and a mobile station whose position is to be obtained. Is transmitted in real time, and the position of the mobile station is obtained in real time based on the position result of the reference station.

  In the present embodiment, the mobile receiver 33 and the mobile GPS antenna 34 that are mobile stations are arranged on the tractor 1, and the fixed receiver 35 and the fixed GPS antenna 36 that are reference stations are arranged at predetermined positions that do not interfere with the work on the field. Established. In the RTK-GPS (real-time kinematic-GPS) positioning of the present embodiment, the phase measurement (relative positioning) is performed at both the reference station and the mobile station, and the phase data observed by the fixed receiver 35 of the reference station is transferred to the mobile receiver 33. Send to.

  The mobile GPS antenna 34 disposed in the tractor 1 receives signals from GPS satellites 37, 37. This signal is transmitted to the mobile receiver 33 for positioning. At the same time, signals from the GPS satellites 37, 37... Are received by the fixed GPS antenna 36 serving as a reference station, measured by the fixed receiver 35 and transmitted to the mobile receiver 33, and the observed data is analyzed and moved. Determine the station location. The position information thus obtained is transmitted to the control unit 30.

  In this way, the control unit 30 in the tractor 1 receives radio waves transmitted from the GPS satellites 37, 37,..., Obtains the position information of the aircraft at set time intervals in the mobile receiver 33, and the gyro sensor 31 and the azimuth sensor. 32, the displacement information and the direction information of the airframe are obtained, and the steering actuator 40, the main transmission actuator 44 and the like are controlled so that the airframe travels along a preset route based on the position information, the displacement information, and the direction information. To do. In the automatic tillage work, the lifting actuator 48 is controlled so that the rotary tiller 24 is at the set depth (plowing depth), and the engine controller 60 controls the rotation speed of the engine 3 so as to be the set rotation speed. . The setting route and work mode are set by the automatic travel setting means 70 disposed at an arbitrary position in the cabin 11. The automatic travel setting means 70 may be constituted by a touch panel or the like and integrated with the display means 49.

  Next, switching control between manual operation (manual travel mode) and automatic operation (automatic travel mode) according to the present invention will be described with reference to FIG.

  The control unit 30 includes a manual travel mode 80, an automatic travel mode 81, an automatic travel preparation mode 82, a manual travel preparation mode 83, and mode switching means 84 for switching between these modes.

  The mode switching means 84 is a means for making a transition to a mode that meets the condition when a transition condition described later is satisfied in each mode.

  In the manual travel mode 80, the steering handle 4, the brake pedal 15, the clutch pedal 16, the main transmission lever 17, the lift lever 18, the PTO transmission lever 19, and the auxiliary transmission lever 20 are independent of the program set by the automatic traveling setting means 70. In this mode, the tractor 1 is caused to travel, work, or be stopped by artificially operating the accelerator lever 21, the forward / reverse switching lever 22, the PTO switch 25, and the like. In the manual travel mode 80, when the automatic travel start condition is satisfied (transition condition 1), the mode switching means 84 shifts to the automatic travel preparation mode 82.

The automatic travel preparation mode 82 is a transition mode from the manual travel mode 80 to the automatic travel mode 81, and the engine 3 is set to the idling speed, and waits until the travel work start command is completed as a travel stop state.
When the data necessary for automatic traveling is available in the automatic traveling preparation mode 82, and the data is not an abnormal value and an automatic traveling start instruction is issued (transition condition 2), the mode switching means 84 switches to the automatic traveling mode 81. To be migrated. Further, when the automatic driving interruption condition is satisfied in the automatic driving preparation mode 82 or when the set time has elapsed after the transition (transition condition 3), the mode switching means 84 shifts to the manual driving preparation mode 83. Is done. In other words, if there is no automatic travel preparation mode 82, the automatic travel mode directly shifts from the manual travel mode 80 to the automatic travel mode 81, so that automatic travel is started even when an abnormality occurs during the transition or during GPS signal processing, May be confused at the start of work. In this embodiment, since there is an automatic travel preparation mode 82, these can be avoided and a smooth transition can be achieved.

The automatic travel mode 81 controls the steering actuator 40 and the brake actuator 41 while detecting the position and direction of the tractor 1 automatically along a preset route according to the conditions set by the automatic travel setting means 70. The engine speed and the transmission are controlled so as to achieve the set speed, and the lift actuator 48 and the like are controlled so as to perform the set work.
When the automatic driving mode is 8 o'clock, the data required for automatic driving is not available, the data is abnormal, the driving stop is instructed, or the automatic driving interruption condition is satisfied (transition condition 4), the mode is switched. The means 84 shifts to the manual travel preparation mode 83.

The manual travel preparation mode 83 is a transition mode from the automatic travel mode 81 to the manual travel mode 80. The program by the automatic travel setting means 70 is ignored, the engine 3 is set to the idling speed, and the travel is stopped.
When the manual travel start condition is satisfied in the manual travel preparation mode 83 (transition condition 5), the mode is switched to the manual travel mode 80 by the mode switching means 84. Further, when the automatic travel start condition is satisfied in the manual travel preparation mode 83 (transition condition 6), the mode switching means 84 shifts to the manual travel preparation mode 83. That is, when the automatic travel mode 81 directly shifts to the manual travel mode 80, there is a possibility of sudden acceleration or a sudden increase in the engine speed. Therefore, when the automatic travel mode 81 transitions to the manual travel mode 80, the vehicle speed is temporarily increased. The minimum speed and the engine speed are reduced to the minimum speed to ensure safety before shifting to manual driving. That is, if the manual travel preparation mode 83 is not provided, the automatic travel mode 81 directly shifts to the manual travel mode 80. Therefore, depending on the position of the speed change operation means, the vehicle may start suddenly. Depending on the position of the steering device, the engine may turn sharply. By providing the manual travel preparation mode 83, these are prevented, and the return to the automatic travel mode 81 can be facilitated.

Next, specific transition control to each mode will be described.
First, the tractor 1 is moved to the work start position in the field by manual operation. When the engine 3 is activated, the vehicle is stopped, and the automatic travel is started in the state where the manual travel mode 80 is set, the control unit 30 determines whether the automatic travel start condition is satisfied. That is, when the vehicle speed is equal to or less than the set speed (the set speed is a slow speed such as 1 km / h that does not start suddenly), the forward / reverse switching lever 22 is neutral, and the clutch pedal 16, the brake pedal 15, and the parking lever 39 are Not operated, the sub-shift lever 20 is in the low speed position, and the engine speed is equal to or higher than the set speed (this set speed is the minimum speed at which the engine 3 is operating, for example, 250 rpm or higher), and The automatic / manual changeover switch 71 is turned on (automatic travel) when the steering handle 4 is in the straight travel position (hereinafter referred to as “the straight travel position” is a substantially straight travel position that hardly turns) and the tractor is not abnormal. It is judged whether it is switched to. When this automatic travel start condition (transition condition 1) is satisfied, the automatic travel preparation mode 82 is entered.
The abnormality of the tractor means that the battery voltage is below the set value (minimum operating voltage), the hydraulic pressure is below the set value (minimum operating pressure), or the cooling water temperature is above the set value (overheat water temperature). Or if the sensor is not responding.

  When shifting to the automatic driving preparation mode 82, whether all data necessary for automatic driving are available, whether the automatic driving interruption condition is satisfied, whether the set time (for example, 1 second) or more has elapsed after shifting to the automatic driving preparation mode 82, If all the data required for automatic driving are determined (transition condition 2), the mode shifts to the automatic driving mode 81, and when the automatic driving interruption condition is satisfied, or after the mode shifts to the automatic driving preparation mode 82, When the set time has elapsed (transition condition 3), the mode shifts to the manual travel preparation mode 83.

  The data necessary for the automatic traveling includes traveling route data, work data, position data from GPS, data from the gyro sensor 31 and the direction sensor 32, and the like.

  The automatic travel interruption condition is that the forward / reverse switching lever 22 is in a position other than the neutral position, the clutch pedal 16 or the brake pedal 15 or the parking lever 39 is operated, or the auxiliary transmission lever 20 is When a position other than the low speed position, the engine speed is less than a set speed (for example, less than 250 rpm), or when an abnormality occurs in the tractor, or when the automatic / manual changeover switch 71 is turned off, or This is a case where the PTO switch 25 is operated on or off. That is, when the operator performs a manual operation after shifting to the automatic travel preparation mode 82, the automatic operation is interrupted so that the manual operation is prioritized.

In a state where the automatic traveling is started and the state is shifted to the automatic traveling mode 81, the control unit 30 does not have data necessary for the automatic traveling or whether the data necessary for the automatic traveling has an abnormal value. Alternatively, it is determined whether the automatic driving interruption condition is satisfied, or whether automatic driving stop is instructed (transition condition 4), and when any one of these conditions is satisfied, the process shifts to the manual driving preparation mode 83.
The case where the data required for automatic driving is not available means that the driving route data and work data are deleted or changed, the position data from GPS does not reach, the gyro sensor 31 and the direction sensor 32 This is the case when no data is input.
When the automatic travel stop is instructed, the automatic travel program ends, the stop command (program) is issued using the automatic travel setting means 70, the set value is changed, or the remote operation is performed. For example, when a stop is instructed.

When the automatic travel is interrupted and the process shifts to the manual travel preparation mode 83, it is determined whether the manual travel start condition is satisfied or the automatic travel start condition is satisfied. When the manual travel start condition is satisfied (transition condition 5), the transition to the manual travel mode 80 is permitted, and when the automatic travel start condition is satisfied (transition condition 6), the transition to the automatic travel preparation mode 82 is permitted.
The manual travel start condition is that the forward / reverse switching lever 22 is neutral, the main transmission lever 17 is shifted from the lowest speed position to a position within the set range, and the accelerator lever 21 is in a low rotation range (for example, 50% of the maximum rotation speed). The automatic / manual changeover switch 71 is turned off (manual). In this way, when the engine 3 is running at a low speed and the airframe is stopped, it is possible to shift to the manual travel mode 80 so as not to cause a sudden start or a sudden turn.

  As described above, the GPS position calculation means for receiving the radio wave transmitted from the GPS satellite 37 and calculating the position of the airframe, the steering actuator 40 serving as the steering drive means for rotating the steering device, the engine rotation control means, An engine controller 60, a main transmission actuator 44 and a sub-transmission actuator 47 serving as transmission means, and a control unit 30 for controlling them, and the steering drive so as to travel along a set route based on the position of the machine body. An automatic travel mode 81 that enables automatic travel by controlling the engine, the engine rotation control means and the speed change means, the main speed change lever 17 and the sub speed change lever 20 as the speed change operation means, the steering handle 4 as the steering operation means and the engine speed. Manual travel that allows the aircraft to travel in response to an artificial operation of the accelerator lever 21 as an operation means In the traveling vehicle having the mode 80, the control unit 30 is connected to an automatic / manual switch 71 serving as a mode switching operation means for switching between the automatic travel mode 81 and the manual travel mode 80. When the vehicle is switched from automatic to automatic, the vehicle speed is equal to or lower than the set speed, the steering device is substantially straight, the forward / reverse switching means is neutral, the clutch is off (the clutch pedal 16 is not operated), and the brake is off. If the brake pedal 15 and the parking lever 39 are not operated, the auxiliary transmission is in the low speed position, the tractor is normal, and the engine speed is equal to or higher than the set speed, the automatic travel preparation mode 82 is switched to. In other words, when the necessary data for automatic driving are available, automatic driving mode 81 is entered and automatic driving is started. In the course of switching from the 80 to the automatic driving mode 81, switched to the automatic travel preparation mode 82, smooth automatic travel in is started without sudden acceleration or sudden turns.

  Further, the control unit 30 is configured so that the vehicle speed is faster than a slow set speed required for shifting from the manual travel mode 80 to the automatic travel preparation mode 82 in the automatic travel preparation mode 82, or the steering device is not in a straight traveling position. Alternatively, when the set time has elapsed from the switching operation by the mode switching operation means 84, the mode shifts to the manual travel preparation mode 83, so that the vehicle speed does not sufficiently decrease to the set speed and does not shift to the automatic travel, or the automatic travel If there is no reaction by the switching operation by the automatic / manual switching switch 71 serving as a mode switching operation means without making a turn at the time of transition, the mode shifts to the manual travel preparation mode 83 without being maintained as it is. When the abnormality is recognized and improved, the automatic travel preparation mode 82 can be restored, or the automatic travel can be stopped and the manual travel mode 80 can be promptly shifted.

  Further, when the automatic travel preparation mode 82 is entered, the control unit 30 changes the engine 3 to idle rotation and performs travel stop control. Therefore, the control unit 30 forcibly stops and then shifts to the automatic travel mode 81. Therefore, it is possible to surely shift to the automatic travel mode 81 and improve safety.

  The control unit 30 is provided with mode switching means 84 for switching between the automatic travel mode 81 and the manual travel mode 80. In the automatic travel mode 81, the control unit 30 is configured so that the forward / reverse switching lever 22 serving as the forward / reverse switching means is other than neutral. Alternatively, the clutch pedal 16 is operated or the brake pedal 15 or the parking lever 39 is operated, the sub-shift lever 20 is other than a low speed, or the automatic / manual changeover switch 71 serving as a mode switching operation means is operated, or When the PTO switch 25 is operated or when the engine speed is equal to or lower than the set speed, the automatic travel is interrupted and the manual travel preparation mode 83 is entered. When the operation is performed or when the rotation speed is not possible in the automatic driving mode 81, the automatic driving is interrupted and the operation is easily performed. Operation will be able to, it is possible to avoid the unintended traveling. In addition, since the automatic travel mode 81 does not directly shift to the manual travel mode 80, there is no sudden vehicle speed change, engine speed change, sudden turn, or the like, and a smooth transition can be achieved. Further, the intention of manual operation is confirmed, and unintended mode switching can be prevented.

  When the manual travel preparation mode 83 is entered, the control unit 30 changes the engine 3 to idle rotation. Therefore, the controller 30 temporarily decreases the rotational speed of the engine 3 and then shifts to the manual travel mode 80, and a sudden speed change occurs. It is possible to smoothly shift to the manual travel mode 80 without occurring.

  In the manual travel preparation mode 83, the control unit 30 shifts to the automatic travel preparation mode 82 when the automatic travel start condition is satisfied. Therefore, the automatic travel mode can be easily returned to the automatic travel mode 81 from the state where the automatic travel is interrupted, and the vehicle starts smoothly. become able to.

DESCRIPTION OF SYMBOLS 1 Tractor 4 Steering handle 17 Main transmission lever 20 Sub transmission lever 21 Acceleration lever 30 Control part 37 GPS satellite 40 Steering actuator 44 Main transmission actuator 47 Sub transmission actuator 60 Engine controller 71 Automatic / manual changeover switch 80 Manual driving mode 81 Automatic driving mode 82 Automatic driving preparation mode

Claims (3)

  GPS position calculation means for receiving radio waves transmitted from GPS satellites to calculate the position of the airframe, steering drive means for rotating the steering device, engine rotation control means, speed change means, and control unit for controlling these An automatic travel mode that enables automatic travel by controlling the steering drive means, the engine rotation control means, and the speed change means so as to travel along a set route based on the position of the airframe, speed change operation means, and steering In a traveling vehicle having a manual travel mode that enables the vehicle to travel in response to an artificial operation of the operation means and the engine rotation operation means, the control unit includes a mode switching operation means for switching between the automatic travel mode and the manual travel mode. Connected, the control unit, when the mode switching operation means is switched from manual to automatic, the vehicle speed is equal to or less than the set speed, the steering device is substantially straight, and The reverse switching means is neutral, the clutch pedal 16, the brake pedal 15, and the parking lever 39 are not operated, the auxiliary transmission is in the low speed position, the running vehicle is normal, and the engine speed is set. When the number of revolutions is higher, the vehicle switches to the automatic travel preparation mode, and when the necessary data relating to the automatic travel is obtained, the travel vehicle is started and the automatic travel is started.   In the automatic traveling preparation mode, the control unit is configured to manually operate when the vehicle speed is faster than the set speed, or when the steering operation means is not in the straight traveling position, or when a set time has elapsed from the switching operation by the mode switching operation means. The traveling vehicle according to claim 1, wherein the traveling vehicle shifts to a traveling preparation mode.   The traveling vehicle according to claim 2, wherein when the automatic travel preparation mode is entered, the control unit changes the engine to idle rotation and performs travel stop control.

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