JP2009245002A - Travel controller for working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To favorably conduct steering control along a set route to the utmost, while reducing a cost using an inexpensive gyro device, by using effectively positional information of a vehicular body found by a GPS positional information calculating means. <P>SOLUTION: This travel controller for the working vehicle is provided with the GPS positional information calculating means 100 for finding the positional information of the vehicular body, the gyro device 57 for detecting azimuth displacement information of the vehicular body, and a gyro information determining means 103 for determining a gyro information proper state where the azimuth displacement information of the vehicular body is detected properly by the gyro device 57, or a gyro information improper state where it is not detected properly, the steering control is conducted based on the positional information of the vehicular body found by the GPS positional information calculating means 100 and the azimuth displacement information of the vehicular body detected by the gyro device 57, when the gyro information proper state is detected, and the steering control is conducted based on only the positional information of the vehicular body found by the GPS positional information calculating means 100, when the gyro information improper state is detected. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a GPS position information calculation means for receiving a radio wave transmitted from a GPS satellite and obtaining position information of a vehicle body at set time intervals, a gyro device for detecting azimuth displacement information of the vehicle body, and the GPS position information calculation Steering control means for controlling steering so that the vehicle body travels along a set route based on vehicle body position information obtained by the means and azimuth displacement information detected by the gyro device. The present invention relates to a traveling control device for a work vehicle.

  Such a traveling control device for a work vehicle can be used by, for example, performing a rice planting operation or a grain harvesting operation while automatically driving a vehicle body along a set route in a field or the like instead of being manually operated by an operator. However, it is possible to reduce the burden of the operator's steering operation. In such a traveling control device for a work vehicle, conventionally, the vehicle body position obtained by the GPS position information calculating means at a set time interval is conventionally used. The current position of the vehicle body and the current direction of the vehicle body are obtained by interpolating the position information with the vehicle body direction displacement information detected while the set time elapses by the gyro device, and the steering control is performed based on the information. The means controls the steering so that the vehicle body travels along the set route. That is, when steering control is performed, the current position of the vehicle body and the current direction of the vehicle body are always obtained based on the vehicle body position information obtained by the GPS position information calculation means and the vehicle body direction displacement information detected by the gyro device. It was a composition. And as said gyro apparatus, it is 3 axis | shafts which can detect each angular velocity displacement around each axial center of the axial center along a vehicle body front-back direction, the axial core along a vehicle body width direction, and the axial core along an up-down direction. A type of gyro device has been used (for example, see Patent Document 1).

JP-A-9-120313

  In the above conventional configuration, the above-described three-axis gyro device is used. For example, the vehicle body largely shakes in the left-right direction around the front and rear axis as the work travels, or around the axis in the horizontal direction. Even if there is a large sway in the front-rear direction, the angular velocity displacement in each direction can be detected, so it is possible to accurately detect changes in the traveling direction of the car body with little error. However, such a three-axis gyro apparatus has a disadvantage in that the structure is complicated and the cost is high.

  Therefore, from the viewpoint of suppressing the cost increase, a low-cost single-axis gyro apparatus, that is, a gyro apparatus having a configuration capable of detecting only angular velocity displacement around one axis core, It can be considered that the vehicle body azimuth displacement information is detected based on the angular velocity displacement around the vertical axis of the work vehicle. However, when such a single-axis gyro device is used, if the vehicle body shakes greatly in the left-right direction around the front and rear axis as the work travels, or if it shakes greatly in the front-rear direction around the axis in the width direction, Due to the movement of the vehicle body, even if the vehicle body is not displaced around the vertical axis, it is detected as an angular velocity displacement around the vertical axis. An error is included, and the steering control of the vehicle body may not be performed satisfactorily.

  The object of the present invention is to effectively use the position information of the vehicle body obtained by the GPS position information calculation means, thereby making it possible to reduce the cost by using a low-cost gyro device, while making the vehicle body a set route. The object of the present invention is to provide a traveling control device for a work vehicle that can perform steering control as well as possible so as to travel along.

A traveling control apparatus for a work vehicle according to the present invention includes a GPS position information calculation unit that receives a radio wave transmitted from a GPS satellite and obtains position information of a vehicle body at set time intervals, and a gyro that detects azimuth displacement information of the vehicle body Steering control so that the vehicle body travels along a set route based on the position information of the vehicle body obtained by the device and the GPS position information calculating means and the azimuth displacement information of the vehicle body detected by the gyro device Steering control means for performing the first characteristic configuration,
A gyro that discriminates whether the gyro information is properly detected by the gyro device and the gyro information is properly detected or the gyro information is not properly detected by the gyro information. Information discriminating means is provided,
The steering control means is
When the gyro information determination unit detects that the gyro information is in an appropriate state, the vehicle position information obtained by the GPS position information calculation unit and the azimuth displacement information of the vehicle body detected by the gyro device Steering control based on, and
When the gyro information determination means detects that the gyro information is in an inappropriate state, the steering control is performed based only on the position information of the vehicle body obtained by the GPS position information calculation means. There is in point.

  That is, the gyro information determination means is in a gyro information appropriate state in which the vehicle body azimuth displacement information is properly detected by the gyro device or in a gyro information inappropriate state in which the vehicle body azimuth displacement information is not properly detected. Determine if it exists. When the gyro information discrimination means detects that the gyro information is in an appropriate state, the steering control means detects the position information of the vehicle body obtained by the GPS position information calculation means and the vehicle body detected by the gyro device. Steering control is performed based on the azimuth displacement information. In other words, the vehicle body follows the set route with as little error as possible by effectively using the vehicle body position information obtained by the GPS position information calculation means and the vehicle body azimuth displacement information detected by the gyro device. Steering control can be performed so as to travel.

  On the other hand, when the gyro information discriminating means detects that the gyro information is in an inappropriate state, the steering control means controls the steering based only on the vehicle body position information obtained by the GPS position information calculating means. It will be.

  As a case where it is detected that the gyro information is in an inappropriate state as described above, for example, the position information of the vehicle body is detected using a single-axis gyro device having a simple configuration and low cost as the gyro device. As the vehicle travels, it can be considered that the vehicle body shakes greatly in the left-right direction around the front and rear axis, or greatly shakes in the front and rear direction around the axis in the width direction. In this way, the single axis gyro device is used. When detecting the position information of the vehicle body, if the vehicle body shakes greatly in the left-right direction around the front and rear axis, or greatly shakes in the front and rear direction around the axis in the width direction, it is erroneously detected as angular velocity displacement around the vertical axis In some cases, a large error may be included in the azimuth displacement information of the vehicle body.

  Therefore, when it is detected that the gyro information is in an inappropriate state as described above, the steering control means performs steering control based only on the position information of the vehicle body obtained by the GPS position information calculation means. The steering control is performed so that the vehicle body travels along the set route by effectively using the detection information of the GPS position information calculation means without using the detection information of the gyro device that may include a size detection error. It is possible to perform as well as possible.

  By the way, the position information of the vehicle body obtained by the GPS position information calculating means is the position of the vehicle body before the set time. However, in a work vehicle working in a field or the like, it is long for a short time until the set time elapses. It is considered that the vehicle does not travel a distance, and there is little possibility that the position in the lateral width direction of the vehicle body greatly deviates from the set route in such a short time. Recently, the processing speed of the GPS position information calculating means has been improved, and the set time, which is the time interval for obtaining the position information of the vehicle body, has been shortened, and based on the detection information of the GPS position information calculating means. Thus, it is possible to perform steering control as well as possible so as to travel along the set route.

  Therefore, according to the first characteristic configuration, the vehicle body position information obtained by the GPS position information calculation means can be effectively used to reduce the cost by using a low-cost gyro device. It is possible to provide a travel control device for a work vehicle that can perform steering control as well as possible so as to travel along a set route.

  According to a second characteristic configuration of the present invention, in addition to the first characteristic configuration, the gyro information determination unit causes the steering control unit to cause the vehicle body to travel along a linear path portion of the set path. If the frequency of determining that the azimuth displacement amount of the vehicle body detected by the gyro device exceeds the set allowable amount is greater than the set frequency when the steering control is performed, the gyro The point is that it is configured to determine that the information is in an inappropriate state.

  That is, when the steering control unit is steered so that the vehicle body travels along the straight path portion of the set route, the vehicle body direction is determined if the gyro device is in an appropriate detection state. The amount of displacement is assumed to be approximately zero or a small value close thereto, but when the amount of azimuth displacement detected by the gyro device is large enough to exceed the set allowable amount, for example, the vehicle body is The gyro information determination unit determines that the gyro information determination unit is in a detection abnormal state because it is abnormal such as a large swaying in the left-right direction around or a large swaying in the front-rear direction around the horizontal axis.

  And, if the frequency of determining such a detection abnormal state is greater than the set frequency, the vehicle body shakes greatly in the left-right direction around the front-rear axis or greatly shakes in the front-rear direction around the axis in the horizontal direction In such a case, the work place where the work vehicle travels along the set route has many irregularities, and the gyroscope detects the vehicle body displacement information properly. Since it can be assumed that the situation cannot be performed, it is determined that the gyro information is in an inappropriate state.

  Therefore, according to the second characteristic configuration, it is possible to accurately determine whether the gyro information is in an appropriate state or the gyro information is in an inappropriate state by the gyro information determining unit.

  According to a third feature configuration of the present invention, in addition to the first feature configuration or the second feature configuration, the steering control means controls the vehicle body so as to travel along a curved route portion of the set route. When the direction control is performed, if the gyro information determination unit detects that the gyro information is in an appropriate state, the steering control is performed based only on the azimuth displacement information of the vehicle body detected by the gyro device. It is in the point which is comprised.

  That is, when the steering control unit performs steering control so that the vehicle body travels along the curved path portion of the set route, in other words, when the vehicle body turns and travels along the curved path portion, Since the displacement amount per unit time of the position along the lateral width direction of the vehicle body is large, a positional deviation occurs between the vehicle body position information before the set time obtained by the GPS position information calculation means and the current vehicle body position. There is a greater risk of being. Therefore, when the steering control means performs steering control so as to travel along the curved path portion, when the gyro information determination means detects that the gyro information is in an appropriate state, that is, to the gyro device. If the vehicle body azimuth displacement information is properly detected, steering control is performed based only on the vehicle body azimuth displacement information detected by the gyro device.

  Therefore, according to the third feature configuration, when the vehicle body travels along the curved route portion of the set route, the detection information of the GPS position information calculation means having a large detection error is not used, and the gyro device appropriately By performing the steering control using only the detected azimuth displacement information of the vehicle body, the steering control can be performed so that the vehicle travels as much as possible along the set route without greatly shifting the position.

  According to a fourth feature configuration of the present invention, in addition to any one of the first feature configuration to the third feature configuration, the GPS position information is detected after the gyro information determination unit detects that the gyro information is in an inappropriate state. There is an emergency stop means for stopping travel of the vehicle body when the position information of the vehicle body is not properly obtained by the calculating means.

  That is, in the state where the gyro information determination unit detects that the gyro information is in an inappropriate state and the gyro device does not properly detect the azimuth displacement information of the vehicle body, If the position information is not properly obtained, the current position and current direction of the vehicle body cannot be obtained as correct values, and steering control cannot be performed so that the vehicle body travels along the set route. The running of the vehicle body is stopped.

  Therefore, according to the fourth feature configuration, when neither the gyro device nor the GPS position information calculation unit can obtain the proper detection information, it is possible to ensure the safety in traveling by stopping the traveling of the vehicle body. it can.

  According to a fifth feature configuration of the present invention, in addition to any one of the first feature configuration to the fourth feature configuration, the steering control means is configured so that the vehicle body has a curved route portion from a straight route portion of the set route. When the vehicle travels along the linear route portion again via the vehicle, the vehicle body starts turning on the curved route portion based on the detection information of the GPS position information calculation means, and then turns. And the detection information of the gyro device between the time when the vehicle body starts turning on the curved path portion and the time when the vehicle finishes turning. When it is determined that the difference between the azimuth displacement amount of the vehicle body obtained based on the vehicle position and the azimuth displacement amount of the vehicle body obtained based on the detection information of the GPS position information calculation means exceeds a set allowable amount, In that it is configured to perform the alarm operation processing for operating a.

  That is, the steering control means detects the detection information of the GPS position information calculation means when the vehicle travels along the straight path portion again from the straight path portion of the set route through the curved route portion. Based on this, the azimuth displacement amount of the vehicle body from when the vehicle body starts turning to the end of turning is obtained. In other words, it is possible to determine in which direction the vehicle body has traveled from the position information of the vehicle body that is obtained at every set time in the straight traveling state before turning, and also at every set time in the straight traveling state after turning. Since the position information of the vehicle body determined in (1) can determine which direction the vehicle body has traveled, the azimuth displacement amount of the vehicle body can be determined from the difference between the directions.

  For example, in the curved route portion of the set route, the ground surface may be rough, such as the traveling road surface being greatly recessed due to repeated turning by the vehicle body, and the gyro device accurately May not be detected. Further, as described above, since the position of the vehicle body changes greatly during a short time when turning, the detection information of the GPS position information calculation means is also considered to have a large error. Therefore, the vehicle body obtained based on the detection information of the gyro device If the difference between the azimuth displacement amount of the vehicle body and the azimuth displacement amount of the vehicle body obtained based on the detection information of the GPS position information calculation means is so large that it exceeds the set allowable amount, there is a high possibility that neither information is accurate. Therefore, the alarm means is operated to notify the manager who manages the work.

  Therefore, according to the fifth feature configuration, in the curved route portion of the set route, neither the detection information of the gyro device nor the GPS position information calculation means is accurate, and the abnormal state such as the running road surface is rough In such a case, for example, by notifying a manager or the like of such a situation, for example, a place where the road surface is rough is excluded from the set route, or the leveling of the part is made so as to be a flat surface with less unevenness. It is possible to take measures such as performing work.

  Hereinafter, a case where an embodiment of a traveling control device for a work vehicle according to the present invention is applied to a combine as a work vehicle will be described.

  As shown in FIG. 1, a cutting part 3 is supported at a front part of a vehicle body supported by a pair of left and right crawler type traveling devices 1, 1 so as to be driven up and down around a horizontal axis P <b> 1 by a cutting lift cylinder 2. A driving unit 4 is provided on the right side of the front part of the vehicle body, a threshing unit 5 is provided on the left side of the rear part of the vehicle body, and a glen tank 6 is provided on the right side of the rear part of the vehicle body. The combine is configured.

  The cutting part 3 includes a weeding tool 7 attached to the tip part, a cereal raising device 8, a cutting blade 9 for cutting the stock of the caused cereal, and a threshing part 5 that receives the cutting cereal meal at the tip side. A vertical conveying device 10 and the like that are transferred to the feed chain are provided.

  Next, the power transmission system is shown in FIG. The output of the engine E mounted on the vehicle body is transmitted to the threshing unit via the threshing clutch 12 that can be turned on and off by the threshing clutch motor 11 and also transmitted to the mission unit 14 via the continuously variable transmission 13. The power from the transmission unit 40 is supplied to the crawler type traveling devices 1 on both the left and right sides, and is also transmitted to the cutting unit 3 via the cutting clutch 16 that can be turned on and off by the cutting clutch motor 15. ing. Although not described in detail in the mission section 14, a slow turning state in which one traveling device 1 is driven at a lower speed than the other traveling device 1, a brake turning state in which one traveling device 1 is stopped, and one traveling A turning state switching mechanism 17 having a well-known configuration is provided that can switch between the reverse turning state in which the device 1 is driven in the opposite direction to the other traveling device 1. The switching operation of the turning state switching mechanism 17 is configured by a swinging operation of a cutting height steering lever 18 to be described later in the lateral width direction of the machine body.

  The continuously variable transmission 13 is linked and interlocked so that a manual shift operation can be performed by a manually operated transmission lever 19 provided in the driving unit 4. The speed change lever 19 is provided at the left portion of the driver seat 20 in the driver 4 so as to be swingable in the longitudinal direction of the fuselage. In other words, when the speed change lever 19 is operated forward from a neutral position located in the middle of the front / rear operation range, the continuously variable transmission 13 increases in traveling speed in the forward direction, and the speed change lever 19 moves rearward from the neutral position. When it is operated to the side, the continuously variable transmission 13 is configured to increase the traveling speed in the reverse direction.

  As shown in FIG. 2, a cross-operated type of cutting that is configured to serve both as a cutting up / down commanding tool for raising / lowering the cutting unit 3 and a turning operation commanding tool for turning the vehicle body left and right is provided at the right side of the driving unit 4. A high steering lever 18 is provided. When the cutting height steering lever 18 is swung rearward, the cutting unit 3 is raised, and when the cutting height steering lever 18 is swung forward, the cutting unit 3 is lowered.

  That is, as shown in FIG. 7, a microcomputer for controlling the operation of the hydraulic control valve 21, the threshing clutch motor 11, the cutting clutch motor 15 and the like that switches the pressure oil supply state to the cutting lifting cylinder 2 is provided. A control device H is provided, and a cutting lift switch 22 that is turned on when the cutting height steering lever 18 is swung backward, and a cutting lowering that is turned on when the cutting height steering lever 18 is swung forward. The switch 23 is provided, and information on these switches is input to the control device H. Then, the control device H switches the hydraulic control valve 21 so that the cutting lift cylinder 2 is lifted when the cutting lift switch 22 is turned on, and hydraulic control so that the cutting lift cylinder 2 is lowered when the cutting drop switch 23 is turned on. The valve 21 is controlled to be switched. Further, a threshing on / off switch 24 and a mowing on / off switch 25 that can be turned on and off by manual operation are provided, and the control device H switches and controls the threshing clutch motor 11 according to the operation state of the threshing on / off switch 24, and the mowing on / off. Control is performed so that the mowing clutch motor 15 is switched according to the operating state of the switch 25.

  Although not described in detail about the linkage configuration, the cutting steering lever 18 and the turning state switching mechanism 17 are mechanically linked. When the cutting height steering lever 18 is swung to the left, the vehicle body turns left, When the swinging operation is performed to the right, the airframe turns to the right, and as the tilt angle from the neutral position of the cutting height steering lever 18 increases, the slow turning state, the brake turning state, and the reverse rotation turning The turning state is sequentially switched, that is, the turning state is sequentially switched so that the turning force is increased.

  The cutting height steering lever 18 and the shift lever 19 are manually operated by a driver seated on the driver seat 20, and the cutting height steering lever 18 and the shift lever 19 are provided separately as described later. It is configured to be able to switch to an autopilot state where it can travel unattended along a preset travel route by operating with a drive operation mechanism.

In addition, as shown in FIG. 2, as shown in FIG. 2, the driving operation mechanism for steering that is positioned in the vicinity of the rear side of the body of the cutting height steering lever 18 and operates the cutting height steering lever 18 in the lateral direction of the body. 26 is provided.
As shown in FIGS. 3 to 5, the steering drive operation mechanism 26 is fixed to the operation panel 27 </ b> A on the front side of the seat of the driving unit 4 by screws through a connector 28 </ b> A as an attachment portion. Further, a screw shaft 30 that is rotationally driven by a steering electric motor 29 (hereinafter referred to as a steering motor) is rotatably supported in a state along the lateral width direction of the machine body, and is screwed into the screw shaft 30. A slide member 32 that includes a female screw portion 31 and slides in the axial direction of the screw shaft 30 as the screw shaft 30 rotates is provided.

  A pair of left and right lever holders 33 serving as lever holding portions are bolted to the slide member 32, and the pair of left and right lever holders 33 are provided at positions where they contact the cutting height steering lever 18 from both the left and right sides. Yes. The pair of lever holders 33 includes a mounting plate 33A and a reinforcing rod 33B fixed to the plate 33A by welding.

  Further, as shown in FIG. 3, the portion extending along the axial direction of the screw shaft 30 of the frame portion 28 is formed in a substantially U-shaped cross section, and is formed on the left and right upper edges of the substantially U-shaped cross section. The guided portion 32a of the slide member 32 comes into contact with the slide member 32 so that the slide member 32 is prevented from rotating around the axis of the screw shaft 30 and is guided to be movable along the axis direction. Yes. Therefore, the upper edge portions of the left and right sides of the frame 28 having a substantially U-shaped cross section prevent the slide member 32 from rotating around the axis of the screw shaft 30 and move the slide member 32 along the axis direction. A guide part G for guiding freely is configured.

  Therefore, as the screw shaft 30 is rotated by rotating the steering motor 29, the female screw portion 31 is screwed and the slide member 32 extends along the axial direction of the screw shaft 30. Thus, the cutting height steering lever 18 can be swung in the horizontal direction of the machine body by the lever holder 33.

  The output shaft 34 of the steering motor 29 and the screw shaft 30 are interlocked and connected by a transmission chain 35. However, the motor-side sprocket 36 is formed to have a larger diameter than the screw shaft-side sprocket 37, and is used for steering. While using a general-purpose inexpensive electric motor having a speed reduction mechanism as the motor 29, the screw shaft 30 is rotated as fast as possible so that the steering operation can be performed quickly.

  In addition, a potentiometer 40 having a detection rotary shaft 39 that is rotatable around the front and rear axis is mounted on a support portion 38 that extends upward from a rear side portion of the frame portion 28 in the middle of the width direction of the fuselage. A swing end portion of the swing arm 41 for detection of the potentiometer 40 and the other end portion of the relay link 42 supported by the slide member 32 so as to be rotatable around the front and rear axis are pivoted via a pin. The detection swing arm 41 of the potentiometer 40 swings as the slide member 32 slides. The slide position of the slide member 32, that is, the cutting height steering lever 18 is supported by the potentiometer 40. The left and right swinging operation amount can be detected.

  As shown in FIG. 2, the steering motor 29 is in an oblique position so that the driver seat 20 is positioned at a substantially central position in the lateral width direction of the driver seat 20 in a plan view and the rear side is directed upward in a side view. When the driver is seated on the driver's seat 20, the feet do not interfere with the steering motor 29 during driving, and do not get in the way when getting on and off.

Next, the drive operation mechanism 43 for shifting for operating the shift lever 19 will be described.
As shown in FIGS. 2 and 6, the drive operation mechanism 43 for shifting interferes with various operation tools provided in the left panel portion of the driving section 4 on the left side of the driver seat 20. It is attached and fixed via a pair of front and rear vertical frames 44 in a state where it is positioned upward so as not to move.

  The drive operation mechanism 43 for shifting has the same structure as the drive operation mechanism 26 for steering, and an electric motor (hereinafter referred to as a shifting motor) is attached to the frame portion 45 fixed to the vertical frame 44. A screw shaft 47 that is rotationally driven by 46 is rotatably supported in a state of having a rotary shaft core along the front-rear direction of the machine body, and includes a female screw portion 48 that engages with the screw shaft 47 to rotate the screw shaft 47. Accordingly, a slide member 49 that slides in the axial direction of the screw shaft 47 is provided. The rear end portion of the operation rod 50 extending in the front-rear direction is pivotally connected to the slide member 49 via the connecting plate 50A so as to be rotatable around the horizontal axis. The portion is pivotally connected to a connector 51 mounted on the speed change lever 19 so as to be rotatable around a horizontal axis.

  Therefore, as the screw shaft 47 is rotated by rotating the speed change motor 46, the female screw portion 48 is screwed and the slide member 49 slides along the axial direction of the screw shaft 47. By moving, the speed change lever 19 can be swung in the longitudinal direction of the machine body with the operation rod 50 and the connecting tool 51.

  The drive operation mechanism 43 for shifting is, like the drive operation mechanism 26 for steering, on a support portion 52 provided so as to extend upward from a position on the driver seat side in the middle in the front-rear direction of the frame portion 45. , A potentiometer 54 having a detection rotating shaft 53 that is rotatable around an axis along the width direction of the machine body is provided. The swing end of the detecting swing arm 55 of the potentiometer 54 and the slide member 49 have a horizontal axis. The other end portion of the relay link 56 that is rotatably supported around is pivotally connected via a pin, and the detection swing arm 55 of the potentiometer 54 swings as the slide member 49 slides. The potentiometer 54 is configured to detect the slide position of the slide member 49, that is, the swing operation amount of the speed change lever 19. There.

  In this combine, the GPS position information calculation means 100 that receives the radio wave transmitted from the GPS satellite 58 and obtains the position information of the vehicle body at set time intervals, and the vertical axis around the vehicle body azimuth displacement information as an example. The gyro device 57 for detecting the angular velocity displacement of the vehicle body, the vehicle body position information based on the vehicle body position information obtained by the GPS position information calculation means 100 and the vehicle body azimuth displacement information detected by the gyro device 57 Steering control means 101 for steering control so as to travel along the vehicle is provided.

First, the GPS position information calculation unit 100 will be described.
A local horizontal coordinate system E (east direction), N (north direction), representing the horizontal direction in the east-west direction and the north-south direction with respect to the gravity direction of the point at an appropriate location on the ground side outside the field to be worked on, As shown in FIG. 10, it is installed at a ground-side reference position whose position (coordinate values in the coordinate systems E, N, and H) is known with high accuracy in H (the height direction from the center of the earth). An antenna 59a for a GPS reference station R (hereinafter also simply referred to as a reference station R) that receives a spread spectrum modulated radio wave (carrier signal) from at least four GPS satellites 58, and a received signal of this antenna 59a is processed. A GPS receiver 59 for obtaining phase information of a carrier wave, and a transceiver 60 as a ground side communication means provided with a transmission antenna 60a for transmitting the carrier wave phase information from the GPS receiver 59 toward the vehicle body side; It is provided.

  On the vehicle body side, an antenna 61a for a GPS mobile station I (hereinafter also simply referred to as mobile station I) that receives radio waves (carrier wave signals) from the GPS satellite 58, and a reception signal of the antenna 61a are processed. A GPS receiver 61 for obtaining carrier phase information and a transceiver 62 as vehicle body side communication means provided with an antenna 62a for receiving transmission information from the ground transceiver 60 are provided.

  As shown in FIG. 11, the GPS receivers 59 and 61 of the reference station R and the mobile station I have the same configuration, and the radio signals received by the respective antennas 59a and 61a are first high-frequency signals. The signals are input to the processing units 63 and 64 and converted to a low frequency. The C / A code analysis unit 65, 66 decodes the satellite number or the like of the low frequency converted signal, and the carrier phase measurement unit 67, 68 generates a C / A according to the satellite number. The carrier wave is reproduced in correlation with the code, and the phase of the carrier wave is measured at set time intervals by the built-in clocks 69 and 70. At the same time, on the basis of information from the C / A code analysis units 65 and 66, the satellite position information and the like are determined by the route message decoding units 71 and 72. Information from each of the above parts is input to the respective control computers 73 and 74, and carrier phase information in each reference station R and mobile station I is obtained.

  Further, the carrier phase information at the reference station R output from the reference station R side computer 73 is transmitted from the transmission antenna 60 a via the ground side transceiver 60, received by the vehicle body side antenna 61 a, and passed through the transceiver 62. Double phase difference information is obtained on the basis of both carrier phase information at the reference station R and the mobile station I, which is input to the mobile station I side computer 74. Based on the double phase difference information obtained from the carrier phase information at the mobile station I and the carrier phase information at the reference station R received by the transceiver 62 using the GPS receiver 61, the reference position That is, the GPS position information calculating unit 100 is configured to obtain the position of the mobile station I, that is, the work vehicle V with respect to the reference station R as time-series GPS position data at predetermined time intervals. The GPS position data obtained by the GPS receiver 61 is input to the control device H.

  Here, the outline of the double phase difference information will be described. Each carrier signal from two different GPS satellites 58 is received by two receiving stations (reference station R and mobile station I), and each GPS satellite 58 is received. Two corresponding phase differences are obtained, and the difference between these two phase differences is called a double phase difference. As a result, the influence of the phase disturbance of the transmission signal at each GPS satellite 58 is removed, and the influence of the synchronization deviation of the clock for measuring the phase of each receiving station is removed. Accurate phase difference information with less influence of the error can be obtained. In order to obtain a position vector r, which will be described later, actually, three independent double phase differences are obtained based on carrier signals from four different GPS satellites 58.

  The position detection of the vehicle body based on the three double phase difference information by the GPS position information calculation means 100 will be specifically described. First, the combine body is positioned at a point where the position coordinate values are known with high accuracy in the local horizontal coordinate systems E, N, and H, and the GPS receivers 59 and 61 on the mobile station side and the reference station side are connected. The three double phase differences are calculated from the received information, and the relative position between the reference station R and the vehicle body is known, so that the integral multiple of the carrier wavelength included in the double phase difference information is uncertain (integer value bias). To confirm. Next, as shown in FIG. 9, the position vector r from the reference station R to the vehicle body is obtained from the three double phase difference information when the vehicle body is moved to an arbitrary point in the field, and the reference position of the reference station R is obtained. And the vehicle body position of the work vehicle V is determined from the obtained position vector r. The detection of the vehicle body position from the GPS reception information is obtained as time-series GPS position data every predetermined time (100 msec).

  Apart from the configuration in which the vehicle body of the combiner receives the radio waves transmitted from the GPS satellite 58 as described above and obtains the vehicle body position information at set time intervals, the vertical axis as an example of the vehicle body azimuth displacement information is provided. A uniaxial gyro device 57 for detecting the angular velocity displacement of the vehicle body around is provided.

  Then, using the control device H, the vehicle body travels along the set route based on the vehicle body position information obtained by the GPS position information calculating means 100 and the vehicle body azimuth displacement information detected by the gyro device 57. The steering control means 100 that controls the steering is configured as described above.

  The set route L is set as data determined with reference to the position coordinates (E, N, H coordinate system) on the ground side. Specifically, when performing the rice planting work to plant the planted cereals in the field to be worked, the driver gets on the rice planting machine and performs the planting work while operating manually. When performing the rice planting work, the rice planting machine is provided with GPS position information calculating means similar to the GPS position information calculating means 100, and when performing the rice planting work, the position information of the body of the rice planting machine is used for the rice planting work. Along with this, processing for obtaining in time series and reading and storing in the storage means is performed in advance.

  Then, the storage information is read by the control device H of the combine, and the control device H creates the setting route L for cutting from the information of the planting area planted in the rice planting work, the information of the travel route, and the like from the storage information. It is configured as follows. Accordingly, the control device H constitutes the setting route creating means 102 that creates the setting route L. At that time, in the case where the number of planting lines by the rice planting machine and the number of harvesting lines of the combine are different, the route is corrected as appropriate according to the difference in the number of lines.

  Describing the set route, as shown in FIG. 9, when the work starts from the work start point st and reaches the end of one work process in which the mowing work is performed along the edge of the uncut grain row, The harvesting work is carried out in a so-called surrounding trimming form in which the body is moved in a direction substantially orthogonal to the body and the next harvesting operation is performed, and such traveling is repeated, You will travel through the entire field to harvest all the planted cereals. When turning at the end portion of the cutting operation stroke, the vehicle is moved forward along the leftward oblique direction from the state of traveling along the straight traveling path in the cutting operation stroke, and then stopped. The vehicle travels backward so that the vehicle is positioned in front of the next straight path that intersects the straight path and the front-rear direction of the vehicle body is in a posture along the next straight path, and then stops traveling, and then along the next straight path. The vehicle is designed to perform a turn traveling for switching a work stroke for traveling straight ahead, that is, a so-called α-turn turning travel. Therefore, in the turning travel for switching the work stroke, not only the direction change operation of the vehicle body in the traveling direction by the operation of the steering motor 29 but also the switching between the forward state and the reverse state by the operation of the speed change motor 46 is performed. Done.

And when performing a cutting work in this field, if it sets to the automatic travel mode by operating the mode setting switch 76, it can be made to drive | work automatically along the setting path | route L set as mentioned above.
That is, when the automatic travel mode is commanded, the control device H converts the current GPS position data obtained by the GPS position information calculation means 100 and the vehicle body direction change information detected by the gyro device 57. The position of the vehicle body at the current time obtained based on the position is obtained as a coordinate value based on the position coordinates (E, N, H coordinate system) on the ground side, and the coordinate value and the travel route L are determined. The current position of the vehicle body with respect to the travel route L is obtained by comparing the data, and steering control is performed so that the vehicle body travels along the set route L. More specifically, the steering motor 29 is operated to steer the vehicle body. At this time, when performing the turning for switching the work stroke as described above, the transmission motor 46 is operated. Thus, the vehicle is switched to the forward traveling state or the backward traveling state. In addition to the control for traveling the vehicle body, the control device H automatically performs the on / off operation of the cutting clutch 16 and the threshing clutch 12 and the lifting operation of the cutting unit 3 together.

  When the vehicle is traveling straight ahead in the automatic travel mode, the control device H uses the gyro device 57 to obtain the position information of the vehicle body determined by the GPS position information calculation means 100 for each set time interval while the set time elapses. The current position of the vehicle body is obtained by correcting based on the detected azimuth displacement information of the vehicle body, and steering control is performed so that the current position of the vehicle body travels straight along the set route L.

  The gyro device 57 determines whether the azimuth displacement information of the vehicle body is properly detected, or whether the gyration information is not properly detected. Information discriminating means 103 is provided, and when the steering control means 101 detects that the gyro information proper state is detected by the gyro information discriminating means 103, the vehicle position information obtained by the GPS position information calculating means 100 is obtained. When the gyro information discriminating unit 103 detects that the gyro information is in an inappropriate state, the GPS position information calculating unit performs the steering control based on the vehicle body azimuth displacement information detected by the gyro device 57. The steering control is performed based only on the vehicle body position information obtained at 100.

  Further, the gyro information discriminating means 103 is detected by the gyro device 57 when the steering control means 101 is steered so that the vehicle body travels along the straight path portion of the set route. If the frequency at which it is determined that the azimuth displacement amount of the vehicle body exceeds the set allowable amount is greater than the set frequency, it is determined that the gyro information is in an inappropriate state.

  When the steering control means 101 performs steering control so that the vehicle body travels along the curved route portion of the set route L, the gyro information determination means 103 detects that the gyro information is in an appropriate state. The steering control is performed based only on the azimuth displacement information of the vehicle body detected by the gyro device 57.

  Further, after the gyro information discriminating means 103 detects that the gyro information is in an inappropriate state, the GPS position information calculating means 100 stops the travel of the vehicle body when the vehicle position information is not properly obtained. Emergency stop means 104 is provided.

  The steering control unit 101 detects the GPS position information calculation unit 100 when the vehicle travels along the linear route portion again from the linear route portion of the set route L via the curved route portion. Based on the information, the vehicle body is configured to determine the amount of azimuth displacement of the vehicle body from the start of the cornering on the curved path portion to the end of the cornering, and the vehicle body turns on the curved path portion. The azimuth displacement amount of the vehicle body obtained based on the detection information of the GPS position information calculation means 100 and the azimuth displacement amount of the vehicle body obtained based on the detection information of the gyro device 57 between the start of turning and the end of the turning travel When it is determined that the difference between and exceeds the set allowable amount, an alarm activation process for activating the alarm means is executed.

  The GPS position information calculation means 100 receives an appropriate reception mode in which radio waves transmitted from GPS satellites are properly received, an unstable reception mode in which the position information of the vehicle body is unstable although radio waves are received, and radio waves. It is configured to switch to any of the unreceivable modes that cannot be received, and is provided with a discrimination state display means 78 that has different display modes depending on the mode switching.

  In addition to the explanation of each mode, when all the radio waves from the four GPS satellites 58 are well received, the proper reception mode is set. In this proper reception mode, the measurement error is about ± 2 cm with high accuracy. The position can be measured. In addition, a state in which the radio wave of any one of the four GPS satellites 58 is not properly received, for example, a direct reception wave in which the radio wave from the GPS satellite 58 is directly received by the antenna 61a, and the GPS satellite 58 When there is an indirect received wave that is received by the antenna 61a after the first radio wave is reflected on the ground, the operation may become unstable, for example, two detection values may be obtained simultaneously as the position information of the vehicle body. There is. Such a state is the unstable reception mode. In this unstable reception mode, the measurement error is about ± 1 m, and the measurement accuracy is deteriorated. If the radio wave from the GPS satellite 58 is not received, it is determined that the reception is impossible. Such a state may occur, for example, when radio waves from GPS satellites are blocked by surrounding obstacles such as other buildings. At this time, the position of the vehicle body cannot be measured.

  As shown in FIG. 1, the discrimination state display means 78 is provided in a state of standing on an upper part of a cabin that covers the driving unit 4 of the vehicle body, and is easy to see so that it can be seen from a basket outside the field 2. Two display lamps 79 and 80 are used. The GPS display lamp 79 is lit with the green display lamp 79a when the GPS position information calculation means 100 is switched to the proper reception mode, and is lit with the yellow display lamp 79b when the GPS position information calculation means 100 is switched to the unstable reception mode. When switched to the disabled mode, the red display lamp 79c is turned on, and the display color as a different display content is switched. Further, the display lamp 80 for the gyro is configured as a blue display lamp that is lit in blue when the detection state of the gyro device 57 is abnormal, and is configured to be turned off when it is normal.

  As shown in FIG. 9, on the outer periphery of the field to be worked, when the combine is automatically traveling, the vehicle body is out of the field so that it does not escape from the field and the vehicle body runs out of control. An optical vehicle body detection device 81 is provided for detecting that the vehicle is going to escape toward the direction. The optical vehicle body detection device 81 is located outside the boundary line created by the laser beam described later from the field. When it is detected that the vehicle is moving toward the direction, an emergency stop signal is transmitted by radio transmission to an emergency receiver 82 provided in the vehicle body to stop the vehicle body.

  In the optical vehicle body detection device 81, light emitting devices 81A that emit laser light along the outer peripheral edge of the field are respectively provided at two diagonal corners, and lasers are provided at the other two corners. A light receiving device 81B for receiving light is provided, and when the light receiving device 81B stops receiving laser light, an emergency stop signal is transmitted by radio transmission to the emergency receiver 82 by the wireless transmitter 81C provided in the receiving device 81B. It is the composition to do.

  Next, the control operation of the control device H will be described based on the flowcharts shown in FIGS. Note that the vehicle body is moved from the heel to the work start point st by manual operation or by another transport vehicle. And this control becomes a structure which starts a process by instruct | indicating a start with the radio | wireless communication apparatus which is not shown in figure by the manager who is outside the field. This process is repeatedly executed every unit time (for example, 20 msec).

  As shown in FIG. 12, if the control mode is the route setting mode, the route setting process based on the stored information as described above is executed (steps 1 and 2). In the automatic travel mode, work start processing is first executed (step 3). That is, the threshing clutch 12 and the reaping clutch 16 are turned on and operated, the speed change lever 19 is shifted to the forward speed for reaping, the reaping portion 3 is lowered, and straight running is started. After starting such straight traveling, straight traveling control is executed (step 4).

Next, the straight traveling control will be described with reference to FIGS. 13 and 14.
The GPS position data calculated by the GPS position information calculating means 100 is read every time a set time (100 msec) elapses (steps 41 and 42), and the position of the vehicle body is calculated from the GPS position data (step 43). Also, the detection information of the gyro device 57 is read every unit time (20 msec) for executing the processing, and the azimuth displacement amount of the vehicle body from the previous detection azimuth is calculated based on the detection information (steps 44 and 45).

  Then, it is determined whether or not the detection information of the gyro device 57 is abnormal (step 46). That is, when steering control is performed so that the vehicle travels straight, specifically, the gyro device 57 detects when the cutting height steering lever 18 detected by the potentiometer 40 is in the neutral position. If the azimuth displacement amount of the vehicle body to be detected is less than the set allowable amount, it is determined that all the azimuth displacement information of the vehicle body is properly detected, and the vehicle body detected by the gyro device 57 is detected. When the azimuth displacement amount exceeds the set allowable amount, it is determined that the vehicle body azimuth displacement information is not properly obtained and is in an inappropriate detection state.

  When the gyro device 57 is in the proper detection state, if the GPS position information calculation means 100 is in the proper reception mode at that time, the gyro device 57 is determined to be in the proper detection state and the green display lamp 79a of the GPS display lamp 79 is set. Lights up (steps 47 and 48). If the GPS position information calculation means 100 is in the unstable reception mode, it is determined that it is in an inappropriate detection state, and the yellow display lamp 79b of the GPS display lamp 79 is turned on (step 49). If the GPS position information calculating means 100 is in the reception incapable mode, it is determined that it is in an inappropriate detection state, and the red display lamp 79c of the GPS display lamp 79 is turned on (step 50). If the improper detection state continues for a set time (0.5 seconds) or longer, it is dangerous to run further, so that the vehicle body is brought to an emergency stop and the red display lamp 79c blinks (step 52). , 54).

  If the GPS position information calculating means 100 is in the proper reception mode, the current position of the vehicle body is obtained based on the position information of the vehicle body calculated from the GPS position data at every set time and the detection information of the gyro device 57 (step) 51).

As shown in FIG. 16, how to obtain the position is described. The process of calculating the position of the vehicle body based on the GPS position data is performed every set time (100 msec), and the amount of azimuth displacement by the gyro device 57 is calculated. The processing to be performed is performed every unit time (20 msec). Based on the position GP1, GP2,... Of the vehicle body obtained from the GPS position data, the position displacement data JD and the vehicle speed information at that time are obtained from that position. The current position is obtained every unit time in consideration of the position displacement amount.
When the explanation is added, as described above, the azimuth displacement data JD is obtained every unit time (20 msec), but the positions GP1, GP2,... Of the base body are measured 100 msec before the current time. Position. Thus, every 100 msec after this position information is obtained, the position information that is the basis (data before 100 msec) is corrected with the position data obtained this time, so that accurate position information can be obtained. ing.
The vehicle speed information can be obtained from information on the operation position of the speed change lever 19 by the potentiometer 54 in the drive operation mechanism 43 for speed change.

  Then, the steering motor 29 is controlled so that the current position of the vehicle body obtained as described above is positioned on the set route L (step 55). For example, when the current position of the vehicle body is far away from the set route L beyond the set amount, the steering height steering lever 18 is operated with the operation position corresponding to the brake turning state as the target position. When the current position of the vehicle body is less than the set amount and the current position of the vehicle body is less than the set amount, the cutting height steering lever 18 is operated with the operation position corresponding to the gentle turning state as the target position. The steering motor 29 is controlled as described above.

  If the GPS position information calculation means 100 is not in the unstable reception mode or the incapable reception mode for more than the set time and is not a gyro check mode as described later, the unstable reception mode The GPS position data is not used only during the reception disabled mode, and the current position of the vehicle body is obtained from the detection information of the gyro device 57, and the vehicle body follows the set route based on the information. The steering motor 29 is controlled to run (steps 52A, 53, 55).

  If it is determined in step 46 that the gyro device 57 is in an inappropriate detection state, the blue lamp 80 as the gyro display lamp is turned on to display an abnormality (step 56). When the number of times that the gyro device 57 is determined to be in the inappropriate detection state is continuously generated more than the set number of times, the gyro device 57 is switched to the gyro check mode as the gyro information inappropriate state that does not use the information of the gyro device 57, The blue display lamp 80 is displayed blinking (steps 57, 58, 59). Further, since the information of the gyro device 57 cannot be used in such a detection abnormal state, steering control is performed based only on the current position of the vehicle body calculated from the GPS position data (steps 60 and 55).

  If the number of times that the gyro device 57 has been determined to be in an improper detection state has not been continuously generated more than the set number of times, if the GPS position information calculation means 100 is in the proper reception mode, the green display lamp 79a is displayed. The steering motor 29 is turned on (steps 61 and 62), the position of the vehicle speed is obtained based only on the GPS position information without using the data of the gyro device, and the position of the vehicle body travels along the set route L. Is controlled (step 65).

  If the GPS position information calculating means 100 is in the unstable reception mode, the yellow display lamp 79b is turned on (step 63), and if the GPS position information calculating means 100 is in the unreceivable mode, the red display lamp 79c is turned on. (Step 64). If the improper detection state continues for a set time (0.5 seconds) or longer, it is dangerous to run further, so the vehicle body is brought to an emergency stop and the red display lamp 79c blinks (steps 66 and 54). ). While the improper detection state is shorter than the set time (0.5 seconds), the state at that time is maintained. In the combine, it is considered that there is little change in the direction during such a short time, so that the traveling is continued in the steering state as it is for a short time.

  When reaching the end point of the straight traveling route that is the target of the cutting operation, the cutting operation is terminated, and it is determined that the vehicle has reached a turning point that turns the vehicle body about 90 degrees toward the straight traveling route that is the next target of the cutting operation. Then, running control for turning is executed (steps 5 to 8).

Next, turning traveling control will be described with reference to FIG.
If it is not the gyro check mode, the detection information of the gyro device 57 is read, the azimuth displacement amount of the vehicle body from the previous detection azimuth is calculated from the detection information, and the current vehicle azimuth is calculated (steps 81, 82, 83). ). Based on the detection information of the gyro device 57, the turning operation for switching the work stroke is executed so as to go to the next straight traveling route inclined about 90 degrees with respect to the previous straight traveling route (step 86). However, in the gyro check mode, the next straight run that is inclined by about 90 degrees with respect to the previous straight drive route based on the information on the current position and current direction of the vehicle body calculated from the GPS position data before the start of turning. The turning operation as described above is performed so as to go to the target direction along the travel route (steps 84 and 86).

  After the cornering is finished, in the cornering state, the azimuth displacement amount of the body from the start of the cornering to the end of the cornering is obtained based on the detection information of the GPS position information calculation means 100. In addition, based on the azimuth displacement amount of the vehicle body that is obtained based on the detection information of the gyro device 57 from when the vehicle body starts turning to the end of turning, the detection information of the GPS position information calculation unit 100 is used. When it is determined that the difference between the vehicle body azimuth displacement amount obtained in this way exceeds the set allowable amount, the red display lamp 79c and the blue display lamp 80 are displayed blinking respectively to perform an alarm operation (step). 10, 11). Therefore, the red display lamp 79c and the blue display lamp 80 constitute alarm means.

  When the explanation is added, the detection information of the GPS position information calculation means 100 can determine in which direction the vehicle body has traveled based on the vehicle body position information obtained for each set time in the straight traveling state before turning. In the straight traveling state after turning, the vehicle body position information obtained at every set time can be used to determine which direction the vehicle body has traveled. Therefore, the abnormality of the detection information can be detected by comparing with the amount of azimuth displacement obtained based on the detection information of the gyro device 57.

  After that, the mowing work is executed along the next straight traveling route, and thereafter, the process is repeated until the mowing work in the field is completed while the vehicle body is driven along the set route. Processing will be executed.

[Another embodiment]
(1) In the above-described embodiment, is the frequency at which the gyro information determination means determines that the vehicle body azimuth displacement detected by the gyro device is in a detection abnormal state exceeding a set allowable amount greater than the set frequency? As a configuration for determining whether or not the detection abnormal state is present, if the number of times that the detection abnormal state is continuously set is equal to or greater than the set number of times, it is determined that the gyro information is in an inappropriate state. In addition, a configuration may be adopted in which it is determined that a state in which the number of times that the detection abnormal state is detected is equal to or greater than the first set number of times within a set time is a detection abnormal state that repeatedly occurs for the second set number of times.

(2) In the above-described embodiment, the azimuth displacement amount of the vehicle body obtained based on the detection information of the gyro device after the vehicle body starts turning and ends turning, and the GPS position information When it is determined that the difference from the azimuth displacement amount of the vehicle body obtained based on the detection information of the calculation means exceeds the set allowable amount, an alarm activation process for operating the alarm means is executed. It is good also as a structure which does not perform such an alarm action process.

(3) In the above-described embodiment, when the vehicle body is steered so as to travel along the straight path portion of the set route, the gyro information determining means determines that the azimuth displacement amount of the vehicle body detected by the gyro device is Only when it is determined that the detection abnormal state exceeds the set allowable amount, the steering control is performed based only on the current position and current direction information of the vehicle body calculated from the GPS position data. When steering the vehicle to travel the vehicle, even if the gyro device is not in an abnormal detection state, the steering control is based only on the current position and current direction information of the vehicle calculated from the GPS position data. Also good.

(4) In the above-described embodiment, when steering control is performed so that the vehicle travels straight along the set route, the current position of the vehicle body is determined based on the detection information of the GPS position information calculation unit and the detection information of the gyro device. However, it may be configured to detect the current position of the vehicle body and the current direction of the vehicle body based on the detection information and to perform steering control based on the information.

(5) In the above embodiment, the work vehicle is provided with a pair of left and right crawler type travel devices, and when making a turn, the turn is performed at a speed difference between the left and right travel devices, and a turn travel for switching the work stroke is performed. Sometimes, it was configured to repeat forward travel and reverse travel, but instead of such a configuration, it may be a wheel type work vehicle, which may be a work vehicle that steers by changing the direction of the wheels, In that case, the steering control means may be configured to operate only the steering actuator that changes the direction of the wheel to steer the vehicle body and not to change the traveling speed.

(6) In the above embodiment, the red display lamp 79c and the blue display lamp 80 are configured to also serve as alarm means, but may be configured to include a dedicated alarm lamp.

(7) Although the case where the work vehicle is a combine has been described in the above embodiment, the present invention can also be applied to various work vehicles such as a rice planting work vehicle and an agricultural tractor.

Combine side view Plan view of the operation unit Side view showing the structure of the drive operation mechanism for steering Notched front view showing the configuration of the drive operation mechanism for steering Notched plan view showing the configuration of the drive operation mechanism for steering Side view showing the configuration of the drive operation mechanism for shifting Control block diagram Diagram showing transmission state Schematic plan view showing work vehicle and planned travel route Schematic side view showing work vehicle and reference station Block diagram showing the configuration of the GPS reception system Flow chart of control operation Flow chart of control operation Flow chart of control operation Flow chart of control operation Diagram showing displacement of detection information over time

Explanation of symbols

57 Gyro device 58 GPS satellite 79c, 80 Alarm means 100 GPS position information calculation means 101 Steering control means 103 Gyro information determination means 104 Emergency stop means

Claims (5)

GPS position information calculating means for receiving a radio wave transmitted from a GPS satellite and obtaining vehicle body position information at set time intervals, a gyro device for detecting azimuth displacement information of the vehicle body, and the GPS position information calculating means A steering control means for controlling steering so that the vehicle body travels along a set route based on vehicle body position information and azimuth displacement information detected by the gyro device. A vehicle travel control device,
A gyro that determines whether the gyro information is properly detected by the gyro device and the gyro information is not properly detected. Information discriminating means is provided,
The steering control means is
When the gyro information determining means detects that the gyro information is in an appropriate state, the position information of the vehicle body obtained by the GPS position information calculating means and the azimuth displacement information of the vehicle body detected by the gyro device are used. Steering control based on, and
When the gyro information determination unit detects that the gyro information is in an inappropriate state, the steering control is performed based only on the position information of the vehicle body obtained by the GPS position information calculation unit. A traveling vehicle travel control device. The gyro information discriminating means is
The azimuth displacement amount of the vehicle body detected by the gyro device when the vehicle body is steered so that the vehicle body travels along a straight path portion of the set route. The traveling of the work vehicle according to claim 1, wherein if the frequency at which it is determined that the detection abnormal state exceeds the set allowable amount is greater than the set frequency, it is determined that the gyro information is in an inappropriate state. Control device. The steering control means is
When steering control is performed so that the vehicle body travels along a curved path portion of the set route, if the gyro information determination unit detects that the gyro information is in an appropriate state, the gyro information The traveling control device for a work vehicle according to claim 1 or 2, wherein the steering control is performed based on only the azimuth displacement information of the vehicle body detected by the device.   After the gyro information discriminating means detects that the gyro information is in an inappropriate state, the GPS position information calculating means stops the travel of the vehicle body when the vehicle body position information is not properly obtained. The travel control device for a work vehicle according to any one of claims 1 to 3, further comprising emergency stop means for causing the work vehicle to stop. The steering control means is
When the vehicle body travels again along the linear route portion from the linear route portion of the set route via the curved route portion, the vehicle body is based on the detection information of the GPS position information calculating means. It is configured to obtain the azimuth displacement amount of the vehicle body from the start of turning on the curved path portion to the end of turning, and
The azimuth displacement amount of the vehicle body obtained based on the detection information of the gyro device and the GPS position information calculating means between the start of the vehicle body turning in the curved path portion and the end of the vehicle turning. The alarm activation process for activating the alarm means is executed when it is determined that the difference from the azimuth displacement amount of the vehicle body obtained based on the detection information exceeds a set allowable amount. 5. The traveling control device for a work vehicle according to any one of 4 above.

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