JP2996699B2 - Steering control of reaper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a pair of left and right operation devices that can be individually turned so as to steer by driving the transmission of driving force to one of a pair of left and right traveling devices. A steering clutch and an actuator for operating the steering clutch are provided, and a steering control sensor for detecting a distance in a lateral direction of the machine body with respect to a stump to be planted in a field; and a steering control sensor. Information on the proximity discriminating means for sampling the detected value and repeatedly discriminating the proximity to the stem and rod at a set cycle, and information on the proximity discriminating means so that the proximity to the stem and rod is maintained within a set appropriate range. The steering clutch to be disengaged among the pair of steering clutches is determined based on the above, and the steering clutch is disengaged with a longer clutch disengagement time as the degree of approach to the set appropriate range increases. Of sea urchin the reaper and steering control means for actuating the actuator steering is provided harvester about the steering control device.

[Conventional technology]

In the steering control device of this kind of reaper,
The longer the clutch disengagement time of the steering clutch that cuts off the transmission of drive power to the pair of left and right traveling devices, the greater the change in the direction of the aircraft. By operating the steering actuator in such a manner, when the automatic running is performed while following the row of stems planted in the field, the followability is improved.

By the way, in order to operate the steering actuator by the steering control means based on the information of the proximity determining means, generally, each time the proximity determining means determines the proximity in the set cycle, it is determined based on the proximity. The steering actuator is operated at the required clutch disengagement time.

[Problems to be solved by the invention]

Conventionally, when returning to a proper range from a state in which the degree of proximity has greatly deviated from the proper range, during the return,
Since the disengagement operation for the steering clutch for each of the plurality of determination results of the proximity determining means is simply performed, when the proximity returns to the appropriate range, the direction of travel of the body and the longitudinal direction of the stem row are changed. Due to the large intersection angle, there is a possibility that the aircraft may not be able to properly follow the stem row. In addition, for example, in the case where the aircraft follows a straight stem row, the presence of the crossing angle is a state in which the aircraft progresses in a direction crossing the stem row. In such a case, even when the approaching degree is within the appropriate range, the approaching degree deviates from the appropriate range as the aircraft advances, and the amount of the deviation tends to increase as the aircraft advances. This tendency becomes more remarkable as the intersection angle becomes larger.

If the approaching degree deviates from the appropriate range as the aircraft advances in the state where the crossing angle exists in this manner, the disengagement operation of the steering clutch suppresses the increase in the disengagement amount. Since the clutch disengagement time is short when it is small, the increase in the amount of disengagement cannot be appropriately suppressed when the crossing angle is large. As a result, it is not only disadvantageous to maintain the approaching degree in an appropriate range, but also there is a possibility that the stem may be deviated from the stem row to be followed.

By the way, if the clutch disengagement time required when the degree of approach deviates significantly from the appropriate range is set longer than the discrimination cycle of the approach degree discriminating means, conventionally, the steering clutch is continuously disengaged. In some cases, the above disadvantages become noticeable.

The present invention has been made in view of the above circumstances,
An object of the present invention is to avoid an increase in the intersection angle between the advancing direction of the body and the longitudinal direction of the stem row, and to more appropriately follow the stem row.

[Means for solving the problem]

A steering control device for a reaper and harvester according to the present invention includes a pair of steering clutches each of which can be separately operated so as to perform steering by operating a transmission of driving force to one of a pair of right and left traveling devices, An actuator for operating the steering clutch is provided, and a steering control sensor for detecting a distance in a lateral direction of the body with respect to a stump to be planted in a field, and a detection value of the steering control sensor is sampled. And a pair of proximity determining means for repeatedly determining the degree of approach to the stem and rod at a set cycle, and the pair based on the information of the approach degree determining means so that the degree of approach to the stem and rod is maintained within a proper setting range. The steering clutch to be disengaged among the steering clutches is determined, and the steering clutch is disengaged with a greater clutch disengagement time as the degree of approach to the set appropriate range increases. Be one and the steering control means for actuating the direction actuator are provided, the characterizing feature is as follows.

A first feature configuration is that the steering control means changes the value of the proximity determined by the proximity determination means this time to a value closer to the set appropriate range with respect to the value of the proximity determined last time,
If the steering clutch to be disengaged is the same as the previous one, the steering actuator is operated until a set time longer than the set cycle has elapsed since the last time the steering actuator was operated. The point is that it is configured not to allow this.

A second characteristic configuration is that the steering control sensor is provided with a pair of sensors spaced apart in the front-rear direction, and the proximity determining means is configured to detect a difference between detection values of the pair of steering control sensors. Obtain the inclination to the stalk row in the body advancing direction, and
It is configured to obtain the distance to the stump and rod in the lateral width direction of the body based on the sum or average of the detection values of the pair of steering control sensors, and output information on the inclination and the distance as information corresponding to the proximity. The steering control means is configured to determine the value of the clutch disengagement time based on both the inclination and the distance.

A third characteristic configuration is that the steering control means is configured to determine the value of the clutch disengagement time by fuzzy inference using both the inclination and the distance.

(Operation)

In the first characteristic configuration, when the operation clutch to be disengaged based on the approach degree determined this time is different from the steering clutch to be operated for disengagement determined based on the approach degree determined last time, Even if the steering clutch to be operated and the steering clutch to be disengaged previously determined are the same, the value of the approach degree determined this time changes to the side away from the set appropriate range with respect to the value of the approach degree determined this time. In this case, by operating the steering actuator at the clutch disengagement time corresponding to the currently determined proximity, the return to the set appropriate range can be promptly performed, but the currently determined proximity is determined. Changes to the side approaching the set appropriate range with respect to the value of the proximity determined last time,
If the steering clutch to be disengaged is the same, the steering actuator is not operated until a set time longer than the set cycle has elapsed since the last time the steering actuator was operated. In this way, the clutch is prevented from being disengaged too much.

In other words, if the steering clutch to be disengaged to be sequentially determined is the same, and the value of the degree of approach is changing to the side approaching the appropriate setting range, maintaining the state allows the appropriate degree of approach. By using the point of return to the range and preventing the steering clutch from being disengaged more than necessary, it is possible to minimize the intersection angle between the aircraft's traveling direction and the longitudinal direction of the stem row. I try to avoid it.

In the second characteristic configuration, a pair of front and rear steering control sensors is provided to enable accurate correction of both the distance to the stem row and the inclination of the body with a small number of steering operations. Both the distance and the inclination of the machine are determined to determine the clutch disengagement time.

In the third characteristic configuration, the value of the clutch disengagement time is determined by fuzzy inference using both the inclination and the distance so that the vehicle can be steered at an accurate clutch disengagement time according to both the position and the attitude of the body with respect to the stem and the row. Is decided.

〔The invention's effect〕

In the first characteristic configuration, since the clutch can be prevented from being excessively disengaged, the followability to the stem row can be improved.

In the second characteristic configuration, both the distance to the stem and the inclination of the aircraft can be corrected accurately with a small number of steering operations.
Steering control performance can be improved.

In the third characteristic configuration, an accurate clutch disengagement time can be determined according to both the position and the attitude of the machine body with respect to the stem row, so that the followability of the machine body with respect to the stem row can be improved.

〔Example〕

Hereinafter, an embodiment in which the present invention is applied to a steering control device of a rush harvester as a reaper will be described with reference to the drawings.

As shown in FIGS. 5 and 6, the rush harvester is provided with a mowing part (2) at the front of a body (V) having a pair of right and left crawler traveling devices (1). The cutting unit (2) includes three weeding tools (3) acting on the root of the planted stem rod, a pair of left and right weeding devices (4) for loosening the entanglement of the planted stem rod, A triggering device that introduces a post-grass stem stick while introducing it (5), a clipper-type cutting blade (6) that cuts off the stem of the stem stick that has been raised, and suspends and holds the upper part of the cut stem stick. A nipping and conveying device (7) and the like, which is transported toward the rear of the aircraft, are provided in that order from the front of the aircraft.

The stems and rods transported to the rear of the machine body by the holding and conveying device (7) are cleaned by a sorting device (8) to remove defective substances such as debris, and are bound by a binding device (9) at predetermined intervals. And, it is designed to be loaded on a loading table (10) behind the body which can be freely tilted. Incidentally, in the drawing, (11) is a boarding control section.

As shown in FIG. 1, the rush harvester includes a pair of left and right steering clutches (14) for turning on and off the transmission of driving force to one of the pair of left and right crawler traveling devices (1). It is provided in the transmission section (15) of (1), and one of the clutches (14) is disengaged to steer. Then, the clutch (1
A pair of left and right steering hydraulic cylinders (16) are provided as steering actuators for turning operation 4), and an electromagnetically operated control valve (17) corresponding thereto is provided.

Of the three weeding tools (3), the one on the most cut side is also configured as a plate-shaped sensor cover (12). A pair of steering control sensors (SF) and (SR) that detect the stem and rods introduced between the center and the weeding tool (3) are arranged at intervals in the longitudinal direction of the fuselage. It is provided in the state where it is. As shown in FIG. 3, the sensor cover (12) is supported by a pair of links (12a) so that the sensor cover (12) can be moved to a storage position moved to the rear side of the fuselage. Although not described in detail, the pair of steering control sensors (SF) and (SR) are stored below the sensor cover (12) in accordance with the position change. In the figure, (12b) is a spring that biases the sensor cover (12) toward the storage position, (12b)
c) is a wire for manual operation for operating the sensor cover (12) to the operation position.

The pair of steering control sensors (SF) and (SR) have the same structure in the front and rear, and the configuration of the front sensor (SF) will be described.

As shown in FIGS. 3 and 4, the sensor (SF) is composed of a sensor bar (13) swingable from the front to the rear of the fuselage around the longitudinal axis of the base end, and a sensor bar (13). A potentiometer (13A) for outputting a value corresponding to the swing angle. Although not shown, the sensor bar (13) is urged by a spring or the like to return to an initial position facing the sensor cover (12) in the lateral direction, and is positioned in the lateral direction where the sensor bar (13) comes into contact with the stalks of rush. Swings rearward in accordance with the vehicle. Accordingly, the potentiometer (13A) outputs information corresponding to the swing angle of the sensor bar (13) from the initial posture. However, the control device (18) shown in FIG.
As shown in FIG. 4, the distance (l) from the inner edge to the surface of the stem in the body width direction is expressed in six steps from 0 to 5 based on the output value of the potentiometer (13A). Is determined as the value of the degree of proximity represented by.
In other words, it is determined that the state is closest to the stem and rod at 0,
It is determined that the larger the number is, the farther the distance (l) from the stem is. Accordingly, it is determined that the initial posture is the most distant at 5. Note that the swing angle range of the sensor bar (13) is divided into six steps so that the values of the six degrees of approach are equally spaced, and the range indicated by 3 is set in steering control described later. The area is set as an area corresponding to the appropriate range.

By the way, as shown in the figure, since the stalks of rushes are planted at intervals on a plant basis, even if there is no change in the approach of the body (V) to the stalks, the body (V) is not changed. With the travel of ()), the sensor bar (13) swings.

Therefore, the control device (18) samples and stores the output of each of the pair of steering control sensors (SF) and (SR) every 4 ms by a sensor input processing unit, and uses a microcomputer as a main unit. The control unit obtains and stores the minimum value of the approach degree during the set cycle (200 ms) every set cycle (200 ms), and at the same time, stores the set number (four pieces)
Is determined as a value corresponding to the distance (l) to the stem rod. The value of the set cycle (200 ms) is a standard vehicle speed (for example, 27 cm / S).
Based on the planting pitch of the stalk and rod (for example, 20 cm) and the diameter of the stalk and rod (for example, 10 cm), it is set so that a plurality of cycles (for example, four cycles) can appear while traveling on the planting pitch. I have. However, the pair of steering control sensors (SF),
When storing the minimum value of each output of (SR), only storage is repeated until the number of storage reaches the set number (four),
After reaching the set number (four), the oldest minimum value is discarded and the latest minimum value is stored.

Further, the control device (18) obtains a minimum value for each of the pair of steering control sensors (SF) and (SR) for each of the set periods, and determines a difference between values before and after the minimum value for the pair of steering control sensors. The angle (θ) corresponding to the inclination of the body (V) with respect to the longitudinal direction is obtained, and the sum of the values before and after is obtained as the distance (λ) corresponding to the distance in the body width direction with respect to the stem row. It is. The process of obtaining the declination (θ) and the gap (λ) as information corresponding to the degree of approach to the stem and rod corresponds to the degree of approach determination means (100). By the way, θ =
The state where 0 and λ = 6 (3 + 3) is the state in which the body (V) follows the stem row in the proper setting state, and the steering is performed so as to maintain this state as described later. Control it.

When the control device (18) obtains the declination (θ) and the gap (λ) as described above, the control device (18) then performs control corresponding to the disengagement time of the left and right steering clutches (14) based on these information. An output (u) is obtained, and steering control is performed by energizing the control valve (17) based on the control output (u).

As shown in FIG. 11, the control output (u) is stored in advance as a table corresponding to the argument (θ) and the gap (λ), and the control device (18) stores this table in the table. The control output (u) will be obtained with reference to this.

The table is calculated by fuzzy inference based on the membership functions shown in FIGS. 7 to 9 and the control rules shown in FIG. The seventh
The figure shows the membership function of the argument (θ), FIG. 8 shows the membership function of the gap (λ), and FIG. 9 shows the control amount used as a weighting factor when calculating the control output (u). 3 shows a membership function of (Z).

To briefly explain the creation of the table, the control rule describes the argument (θ) and the gap (λ) as two fuzzy variables of the antecedent part, and the control amount (Z) as the consequent part. The degree of conformity (grade) of the argument (θ) and the distance (λ) to the control rule is determined by the smaller of the degrees of conformity to the membership function (FIGS. 7 and 8). Degree. Further, the control amount (Z) is obtained from the membership function (FIG. 9) based on the degree of conformity thus obtained. Incidentally, when a plurality of control rules are applied to the declination (θ) and the gap (λ), the control amounts (Z) for each control rule are obtained by the above-described procedure, and the control amounts (Z) are calculated. The value obtained by averaging the loads is defined as the final control amount (Z).

The control output (u) is obtained by multiplying the control amount (Z) obtained in the above procedure by the basic output (110 ms in this embodiment).

In FIG. 11, the upper value indicates the control amount (Z), and the lower value indicates the control output (u). In the calculation of the control amount (Z), arithmetic processing such as rounding is performed. Further, the control output (u) is determined in the range of +272 to -272, and the value of +273 or more is +272. , −
A value of 273 or less is -272. In addition, a negative control output (u) indicates that the left steering clutch (14) is disengaged to steer to the uncut side, and a positive control output (u) indicates a right steering clutch (14). ) Indicates that the vehicle is steered to the cut side.

The control output (u) of the table created as described above is
When the value of the declination (θ) is inclined from the appropriate setting range to the uncut side and the value of the distance (λ) is deviated from the proper setting range to the uncut side, the declination (θ) ) Is inclined from the setting appropriate range to the cut side, and the value of the distance (λ) is larger than when the value is shifted from the setting appropriate range to the cut side. The steering amount is set to be larger than the steering amount to the uncut side so as to prevent the stalk rod from being pushed into the row of stems and the stem rods from being depressed.
Incidentally, this corresponds to, for example, a comparison of the control output (u) in the case of SF = 1 and SR = 4 or 5 and the control output (u) in the case of SR = 1 and SF = 4 or 5.

When the control valve (17) is energized to obtain the control output (u) based on the above table, the following points must be considered. That is, since there is a delay time from the start of energization to the control valve (17) to the actual disengagement of the steering clutch (14), if the energization time to the control valve (17) is too short, the actual In this state, the steering clutch (14) cannot be disengaged. Therefore, a short time (eg, 88m) at which the steering clutch (14) can be disengaged and operated.
It is useless to output a clutch disengagement time shorter than s), so it is preferable not to output such a short clutch disengagement time.

Although not shown, the steering clutch (14) is configured so that it can be manually turned off manually. Also, in FIG. 1, (19) is an alarm device as an alarm device that operates as an alarm when the control operation of the steering control is stopped, (20) is a traveling transmission, and (21) is automatically. An automatic switch for instructing the control device (18) to perform steering control, and (E) is an engine. In addition, using the control device (18), the proximity determining means (100)
The control valve (17) is energized based on the control output (u) so that the body (V) follows the stem row based on the information of the approach degree determining means (100). A steering control means (101) for performing steering control is configured.

To explain the steering control, the process for obtaining the value of the control output (u) is performed at the set cycle (200 m) as described above.
In step s), the actual output processing based on the discrimination information is performed using an output cycle (800 ms) having a value longer than the set cycle for obtaining the value of the control output (u). That is, when the steering direction of the control output (u) obtained this time is opposite to the previous one, and when the control output (u) becomes larger than the previous one even if the steering direction is the same, the current output is obtained immediately. The value of the control output (u) is output. On the other hand, if the control output (u) obtained this time changes in the same direction as the previous steering direction and in a direction approaching the set appropriate range, the output cycle (800 ms) from the time when the previous output was started. Is not output until the time elapses.

Therefore, if the deflection angle (θ) and the gap (λ) of the rush can not return to the set appropriate range in the previous steering operation, the control output corresponding to the current state is performed. As a result, the steering operation is repeatedly and continuously performed, and the return to the proper setting range can be accurately performed.
Then, when the vehicle is returning to the proper setting range, the steering operation is temporarily stopped to prevent over-control.

The control operation of each process for the steering control described above is performed when at least one of the pair of steering control sensors (SF) and (SR) approaches within a set distance with respect to the stem row. Starting with the detection of the state of the pedestal, and the state where both of the pair of steering control sensors (SF) and (SR) are apart from the stem row by a set distance or more for a set time or more. The detection is automatically switched based on the information of the pair of steering control sensors (SF) and (SR) so that the detection is stopped in accordance with the detection.

In addition, the pair of steering control sensors (S
F) and (SR) return to the front side when there is no planted stem rod, and the corresponding proximity is 5 at the maximum, and when it comes into contact with the stem rod, it outputs a value of 0 to approx. Will be.
Therefore, when the proximity of one of the front and rear sensors is less than 5, it is determined that the control condition is satisfied, and the mowing work and the steering control can be started.

Next, after the control condition is satisfied and the steering control is started, when the body (V) reaches the end of the work stroke and the planting stem stick disappears, the pair of steering control sensors (SF), ( SR) both return to the initial position, and the corresponding proximity is the maximum of 5. Therefore, if the state in which both the proximity of the front and rear sensors reaches a maximum of 5 continues for a set time or longer, it is determined that the control condition is not satisfied, and the mowing work and the steering control can be stopped.

Hereinafter, the operation of the control unit of the control device (18) will be described with reference to the flowchart shown in FIG.

When power is supplied to the control device (18) and the automatic switch (21) is turned on to start the operation,
After performing initial setting processing for executing processing such as setting the values of various variables to initial values, based on the proximity value detected by the pair of steering control sensors (SF) and (SR). It is determined whether the control condition is satisfied as described above.

If the control condition is not satisfied, the control operation is stopped and waited until the control condition is satisfied. If the control condition is satisfied, the control operation is started.

When the control operation is started, the minimum value is obtained at each set cycle as described above from the detection data of the pair of steering control sensors (SF) and (SR), and the stored minimum value is set to the set number (four pieces). ) Is determined as to whether or not a stack flag indicating whether or not the number has reached ON has been reached.

If the stack flag is not ON, the process of saving the minimum value to the storage stack is repeated. However, when the data saved in the stack is full, that is, when the minimum value has reached the set number, the data with the minimum value among the data saved in the stack is selected and the stack flag is turned ON. Become.

If the stack flag is ON, discard the oldest data in time, save the data corresponding to the newly obtained minimum value on the stack, and select the data with the minimum value in the stack become.

After selecting the minimum value in the stack, the control output (u) is calculated from the combination of the minimum value selected for each of the front and rear steering control sensors (SF) and (SR) in the table (see FIG. 10). ).

Next, it is determined whether the calculated control output (u) has the same steering direction as the previously obtained control output and is smaller, that is, in a direction in which the degree of approach to the rush approaches the set appropriate range. It is determined whether or not the output of the control valve (17) is maintained. If the output is smaller, the current output state of the previous control output is maintained. ) Is energized.

However, as described above, the current output state based on the previous control output is based on the value obtained last time without performing the output process based on the value obtained this time from the start of the current output until the end of the output cycle. Continue output processing.

After executing the output process, the processes from the process of determining whether or not the control condition is satisfied are repeated until the power is turned off.

(Another embodiment)

In the above embodiment, a pair of steering control sensors (SF),
(SR) has been described as a contact type provided with a sensor bar (13) contacting the stalk of rush, but the specific configuration can be changed in various ways such as a non-contact type.

Further, in the above-described embodiment, the case where the steering control sensor is provided in a pair of front and rear so as to be able to determine the inclination of the body with respect to the stem row is exemplified, but with one steering control sensor, in the body width direction. The steering control may be simplified so as to be performed based on only the information on the degree of approach. When a pair of front and rear sensors is provided, the distance to the stem may be obtained by averaging the detection values of the sensors.

Further, in the above-described embodiment, the case where both the start and the stop of the control operation of the steering control are automatically performed is exemplified. However, only the stop is automatically performed, and the start is performed artificially. Is also good.

In the above embodiment, the steering control sensors (SF), (S
R) The example in which the sampling period of the detection value and the output period of the control output are made constant has been described, but the sampling interval and the output period can be switched according to the vehicle speed so as to have a constant traveling distance interval. Alternatively, the vehicle speed may be detected and automatically switched or may be changed according to the vehicle speed. Further, for example, the control output (u) is selected so that a control amount can be selected according to a difference in a field condition such as a wet field or a dry field.
May be provided so that the table to be used can be switched by a changeover switch, or automatically switched according to the vehicle speed.

In the above-described embodiment, the alarm device (19) is used as an alarm device that operates as an alarm when the steering control device stops the control operation.
Is provided, but instead of the alarm (19), a lamp or the like for indicating whether the control operation is in the start state or the stop state is provided, or, for example, the engine (E) is automatically stopped. It may be. However, the alarm means may be omitted for the implementation.

In the above embodiment, the case where the present invention is applied to a rush harvester is illustrated. However, the present invention can be applied to a combine or the like, and the specific configuration of each part can be variously changed. For example, the traveling device (1) may be a crawler type or a multi-wheel type.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the structure shown in the attached drawings.

[Brief description of the drawings]

The drawings show an embodiment of a steering control device of a reaper and harvester according to the present invention. FIG. 1 is a block diagram of a control configuration, FIG. 2 is a flowchart of a control operation, and FIGS. Fig. 5 is a plan view of a rush harvester,
6 is a side view, FIGS. 7 to 9 are explanatory diagrams of membership functions, FIG. 10 is an explanatory diagram of control rules, and FIG. 11 is a table of control output. (SF), (SR): Steering control sensor, (V): Airframe, (θ): Tilt, (λ): Distance, (1): Traveling device, (14): Steering Direction clutch, (16) ... Steering actuator, (100) ... Approach discrimination means, (101) ...
... Steering control means.

Claims (3)

(57) [Claims] A pair of steering clutches (14), each of which can be separately operated so as to steer by turning off the transmission of driving force to one of a pair of left and right traveling devices (1), and an operation thereof. An operation actuator (16) for operating the direction clutch (14), and a steering control sensor (SF), (SR) for detecting a distance in a lateral width direction of the fuselage with respect to a stump to be planted in a field; An approach discrimination means (100) for sampling the detection values of the steering control sensors (SF) and (SR) and repeatedly discriminating the approach to the pedicle at a set cycle; The steering clutch (14) of the pair of steering clutches (14) to be disengaged based on the information of the approach degree determining means (100) so as to be maintained within the range.
And the steering actuator (1) is operated so that the steering clutch (14) is disengaged with a longer clutch disengagement time as the degree of approach to the set appropriate range is greater.
6) A steering control device for a reaper, which is provided with a steering control means (101) for activating the above-mentioned operation. 6) The steering control means (101) includes: When the value of the determined degree of approach changes to a side approaching the set appropriate range with respect to the value of the degree of proximity previously determined and the steering clutch (14) to be disengaged is the same as the previous time, Steering control of a reaper that is configured not to operate the steering actuator (16) until a set time longer than the set period has elapsed since the last time the steering actuator (16) was operated. apparatus. 2. A steering control device for a reaper according to claim 1, wherein a pair of said steering control sensors (SF) and (SR) is provided at an interval in the front-rear direction. The approach degree determining means (100) includes the pair of steering control sensors (SF),
Based on the difference between the detected values of (SR), the inclination (θ) with respect to the stem row in the body advancing direction is obtained, and the sum of the detected values of the pair of steering control sensors (SF) and (SR) or The distance (λ) to the stem and rod in the lateral width direction of the body is obtained based on the average, and information on the inclination (θ) and the distance (λ) is output as information corresponding to the degree of approach, and the steering is performed. The control means (101) is a steering control device for a reaper, configured to determine the value of the clutch disengagement time based on both the inclination (θ) and the distance (λ). 3. The steering control device for a reaper according to claim 2, wherein the steering control means (101) uses fuzzy inference using both the inclination (θ) and the distance (λ). And a steering control device for the reaper.