JPH0787725B2 - Steering control information detector for work vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a steering control information detection device for a work vehicle that detects steering control information for automatically traveling a work vehicle along a work target. .

[Conventional technology]

For example, if a steering control information detecting device for combine is described as an example, conventionally, a contact-type sensor bar having a sensor bar that is connected to a stem culm as a work object to be introduced into the mowing unit along with traveling of the airframe is used. A steering control sensor is provided, and the steering control sensor is used to detect the positional deviation in the lateral direction of the machine body with respect to the stems.

[Problems to be Solved by the Invention]

In the above-mentioned conventional configuration, since the position information at one point in the machine longitudinal direction cannot be detected, there is a disadvantage that local unevenness of the stem culm row as a work object lined up in the machine traveling direction is affected, for example, every set time. Alternatively, it is necessary to perform processing such as determining the position of the machine body with respect to the work target based on information obtained by averaging a plurality of pieces of detection information detected for each set traveling distance. Therefore, when the position of the machine body is discriminated, the position of the work object is passed, and there is a disadvantage that the tracking of the work object is delayed.

Further, the deviation of the orientation of the machine body with respect to the direction of the work target row aligned in the machine body traveling direction cannot be detected, and improvement has been desired.

In addition, using a non-contact type distance sensor such as an ultrasonic sensor,
It is also considered to detect the distance to the work object, but in the past, since the distance sensor was fixed in a state in which the direction could not be changed with respect to the aircraft, the same as when using the above contact type sensor. In addition, only the position information at one point can be detected.

By the way, a means for providing an image pickup means for picking up the work object on the front side of the machine body in the two-dimensional direction and detecting the position of the work object in the two-dimensional direction with respect to the machine body based on the picked-up image information is also considered. However, since the image processing is involved, there is a disadvantage that the device configuration becomes complicated and expensive.

The present invention has been made in view of the above circumstances, and a first object thereof is to reduce the position of a work object in the two-dimensional direction with respect to the machine body while simplifying the device configuration. It is to be able to detect before traveling up to.

A second object is to enable the position of the work object to be accurately detected regardless of changes in the traveling speed of the machine body.

[Means for Solving the Problems]

A first characteristic configuration of a steering control information detection device for a work vehicle according to the present invention is a non-contact type distance sensor that detects a distance to a work object lined up in a machine body traveling direction. Scanning means for scanning the distance sensor to detect distances to a plurality of work objects located in front of the fuselage at least in front of the attachment position of the distance sensor provided on the fuselage at intervals in the width direction. Sampling means for sampling the distance information detected by the distance sensor at each set interval in a state where the distance information corresponds to the scanning angle by the scanning means, and the plural distance information and the scanning angle sampled by the sampling means. Linear calculation means for obtaining an approximate straight line corresponding to the work object row arranged in the machine body traveling direction based on the information. To the point it is there.

A second characteristic configuration is provided with speed detecting means for detecting a traveling speed of the airframe, and the scanning means is configured to increase the traveling speed of the distance sensor as the traveling speed increases. The scanning speed is automatically adjusted based on the detection information of the detection means.

[Work]

In the first characteristic configuration, the non-contact type distance sensor detects distances from a lateral side portion of the machine body with respect to the work object to a plurality of work objects located in front of the machine body with respect to a mounting position of the sensor. While scanning as described above, by sampling a plurality of distance information, it is possible to detect distance information in a two-dimensional direction with respect to a plurality of work object rows arranged in the machine advancing direction, and to sample the plurality of distances. Based on the information and the scanning angle information, an approximate straight line corresponding to the work object row arranged in the machine body signal direction is obtained.

Since the distance information detected by the distance sensor is sampled at every set interval, if the scanning speed is constant,
When the traveling speed of the aircraft is high, the number of work objects that can be detected is smaller than when the traveling speed is low, because the distance that changes with respect to the same work object is repeatedly detected. And the effective scanning range becomes small.

Further, as the traveling speed increases, the sampling interval of the distance to the work object becomes rougher than when the traveling speed is low.

Therefore, in the second characteristic configuration, the traveling speed is automatically adjusted so that the traveling speed of the distance sensor corresponds to the traveling speed of the airframe.

〔The invention's effect〕

Therefore, according to the first characteristic configuration corresponding to claim 1,
Although using a non-contact type distance sensor that originally detects one-dimensional distance information, an approximate straight line corresponding to the work target row lined up in the machine traveling direction, that is, position information across the two-dimensional direction with respect to the work target, It can be detected before the aircraft has traveled to that position.

Further, according to the second characteristic configuration corresponding to claim 2, since the traveling speed of the distance sensor is automatically adjusted according to the traveling speed of the machine body, the work object detected by the distance sensor in the machine body traveling direction side. It is possible to prevent the scanning range in (3) from narrowing due to an increase in traveling speed.

As a result, the position of the machine body with respect to the work target row can be accurately corrected.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 4, a control section (2) is provided on the right front part of a vehicle body (V) equipped with a pair of left and right crawler traveling devices (1), and a threshing device (3) is mounted on the rear side thereof. Has been done. Further, a reaper (4) is provided at a front portion of the machine body (V) so as to be able to move up and down, thereby forming a combine as a work vehicle.

As shown in FIGS. 1 and 4, the control section (2) is
Uncut culm (H) as a work target planted in the field
It is located on the most mown side in the lateral width direction of the machine body, and is provided so as to project to the mown side from the uncut stem row (L ₁ ) arranged in the machine body traveling direction.

Then, the control section (2), which is in a state of being spaced apart from the uncut culm (H) in the lateral direction of the body, is detected at the lower end without contact with the distance to the uncut culm (H). Reflective ultrasonic sensor (S ₁ ) as a non-contact distance sensor
, Are attached so that they can be scanned in the horizontal direction.

Explaining the scanning range of the ultrasonic sensor (S ₁ ), as shown in FIG. ₁ , a plurality of uncut stems located in front of the fuselage with respect to the mounting position of the ultrasonic sensor (S ₁ ). In the state where the position in the lateral direction of the fuselage with respect to the uncut stem row (L ₁ ) in which the fuselage (V) is lined up in the traveling direction of the fuselage is in an appropriate state so that the distance to (H) can be detected by one scan. With reference to the state in which the ultrasonic sensor (S ₁ ) faces the front of the machine body, a range of a set angle (set to 60 degrees) is scanned toward the uncut side.

As shown in FIG. 5 and FIG. 6, the ultrasonic sensor (S ₁ ) is arranged around the vertical axis (P) with respect to the support member (5) fixed to the lower portion of the control section (2). A swing arm (6) pivotally mounted on the lower surface of the ultrasonic sensor (S ₁ ) for scanning the ultrasonic sensor (S ₁ ) around the vertical axis (P). Is stuck to. An elongated hole (7) is formed in the swing arm (6), and a rotary plate (9) having a pin (8) engaging with the elongated hole (7) is provided.
A stepping motor (10) as a scanning means that is rotatably pivoted around a vertical axis (Q) and rotationally drives the rotary plate (9) is provided with the ultrasonic sensor (S ₁ ) of the support member (5). ) Is attached to the rear side.

In FIG. 5, (S ₂ ) is a scanning angle detecting sensor using a potentiometer for detecting the direction of the ultrasonic sensor (S ₁ ), that is, the scanning angle (θ) at the present time.

However, the scanning angle (θ) is the ultrasonic sensor (S ₁ )
Is detected as the angle from the state in which the vehicle faces the front of the machine body to the lateral direction of the machine body.

Then, by rotating the stepping motor (10) at a set speed, the ultrasonic sensor (S ₁ ) is reciprocally scanned within the set angle range, and at every set interval (10 ms), a detection distance is detected. (1) A plurality of samples are sampled, and the positional relationship between the uncut stem row (H) and the machine body (V) is obtained based on the sampled plurality of distance information in the two-dimensional direction. I am doing it.

By the way, if the scanning speed (ω) of the ultrasonic sensor (S ₁ ) is kept constant, the following inconveniences occur. Therefore, as the traveling speed (v) increases, the scanning speed (ω) increases.
In order to increase the vehicle speed, the vehicle body (V) is automatically adjusted according to the traveling speed (v).

That is, when the traveling speed (v) of the vehicle body (V) becomes faster than the scanning speed (ω), for example, when the ultrasonic sensor (S ₁ ) scans in the lateral direction from the state of facing the front surface of the vehicle body. The distance information detected by the ultrasonic sensor (S ₁ ) becomes a state in which the distance to the same uncut culm approaching toward the aircraft side as the aircraft progresses is also detected. The information corresponding to the stem culm (H) may be lost. Further, when the ultrasonic sensor (S ₁ ) scans from the state in which it is oriented in the lateral direction of the machine body in the front direction of the machine body, there is a risk that the intervals of the distances sampled at every set interval become rough, and the traveling speed ( If v) becomes faster, there is a disadvantage that the actual detection range of the distance information detected within the scanning range of the ultrasonic sensor (S ₁ ) becomes narrower.

Therefore, by automatically adjusting the scanning speed (ω) according to the traveling speed (v) of the machine body (V), even if the traveling speed (v) changes, there is no substantial difference in the distance detection range. To do so.

The scanning speed (ω) is adjusted by changing the rotation speed of the stepping motor (10) for scanning.

Next, a control configuration for obtaining an approximate straight line corresponding to the uncut culm row based on the distance information detected while scanning the ultrasonic sensor (S ₁ ) in the horizontal direction will be described.

As shown in FIG. _1, with the detection distance information by the ultrasonic sensor (S ₁ ) corresponding to the information of the scanning angle (θ) by the stepping motor (10) as the scanning means, the set interval is set. Sampling means (100) for sampling for each, a straight line for obtaining an approximate straight line corresponding to the uncut stem row based on the plurality of distance information sampled by the sampling means (100) and the scanning angle information Steering control is performed so that the machine body (V) automatically travels along the uncut stem row based on the calculation means (101) and information on the approximate straight line obtained by the straight line calculation means (101). A control device (11) using a microcomputer, which constitutes each steering control means, is provided.

In FIG. 1, reference numerals (12L) and (12R) denote steering clutch brakes (13L) for switching the left and right crawler traveling devices (1) to a drive state and a drive stop state, respectively.
(13R) is the steering clutch brake (12L), (12R)
Operating hydraulic cylinders, (14L) and (14R) are control valves for operating the hydraulic cylinders (13L) and (13R), (15) is the transmission case of the crawler traveling device (1), and (16) is its The transmission for transmitting the output of the engine (E) to the mission case (15), (S ₃ ) is the transmission case (1)
5) A vehicle speed sensor as a speed detecting means for detecting the traveling speed (v) of the machine body (V) based on the drive rotational speed of the input shaft.

Explaining the automatic traveling of the machine body (V), the position of the uncut stem culverts lined up in the machine body traveling direction in the machine body lateral width direction is
In a state of being located within the proper cutting range of the cutting unit (4), and so that the orientation of the machine body (V) with respect to the length direction of the uncut stem culm is maintained within the set range, Steering will be controlled.

In addition, as shown in FIG. 2, an approximate straight line (f (x) = ax +) corresponding to the uncut stem culm lined up in the machine advancing direction, as shown in FIG.
b) A distance measurement process described later for obtaining (see FIG. 1) is performed, and a lateral position of the straight line with respect to the origin, that is, a distance (b) in the lateral direction of the aircraft with respect to a mounting position of the ultrasonic sensor (S ₁ ). It is determined whether or not the absolute value of is less than or equal to a preset setting value (B). If it is not less than or equal to the setting value (B), the steering clutch brakes (12L), (1
2R) is turned off once during the set time to correct the traveling direction of the aircraft (V).

Then, subsequently, it is determined whether or not the absolute value of the slope (a) of the straight line is equal to or less than a preset value (A). If the absolute value is not equal to or less than the preset value (A), the steering clutch is determined. The brakes (12L) and (12R) are turned once for the set time to correct the traveling direction of the aircraft (V).

Next, the distance measuring process for obtaining the approximate straight line will be described based on the flowchart shown in FIG.

The vehicle speed sensor (S) is set so that the operating speed (ω) of the ultrasonic sensor (S ₁ ) increases as the traveling speed (v) of the machine body (V) increases with the start of the distance measurement process. Based on the traveling speed (v) detected in ₃ ), the operation speed (ω) is set from the following equation (i).

ω = K ₁ · v · ω + ω ₀ (i) where K ₁ is a preset constant and ω ₀ is the traveling speed (v)
Is the initial value of the scanning speed corresponding to zero.

Then, while the ultrasonic sensor (S ₁ ) is scanned once, the detection distance (l) of the ultrasonic sensor (S ₁ ) detected at every set interval (10 ms) is set to the scanning angle detection value. Together with the scanning angle (θ) detected by the sensor (S ₂ ), sampling is repeatedly performed until the set number (N) corresponding to one scan is reached, and the detected distance data (ln) and scanning angle data (θn ) And are stored in the first array (Dn) for storing time series data.

That is, the detection distance (l) of the ultrasonic sensor (S ₁ ) detected at each set interval (10 ms) together with the scanning angle (θ) detected by the scanning angle detection sensor (S ₂ ). ,
The process of repeatedly sampling until the set number (N) is reached corresponds to the sampling means (100).

Next, the number of data (n) is initialized to 1, and the reference distance data (for determining continuity of the detected distance data in order to remove unnecessary noise data from the detected distance data (ln)). Initialize the value of (lp) to the value of the first detection distance data (l ₁ ).

Then, it is determined whether or not the absolute value of the difference between the reference distance data (lp) and the next detected distance data (ln _{+ 1} ) is less than or equal to a preset set value (C), and the set value is set. If not (C) or less, it is determined that the continuity of the detected distance data has been interrupted, and the value of the reference distance data (lp) is updated to the value of the next detected distance data (ln _{+ 1} ). .

That is, since the uncut culm (H) is planted in the field at every set interval, the detected distance data (ln) is a continuous date on the surface side of each stock. , The data will vary greatly between stocks.

Therefore, in order to exclude the data detected between the strains,
The continuity of the detection distance data (ln) is checked, and the discontinuous data is removed as noise.

That is, when the absolute value of the difference between the reference distance data (lp) and the next detected distance data (ln _{+ 1} ) is less than or equal to the set value (C), the value of the detected distance (l). And the scanning speed (ω) by the stepping motor (10), the value of the detected scanning angle data (θn) is corrected using the following equation (ii).

θn = θn−Δθ (ii) However, Δθ = ω · ln / 170.

In the above equation, the denominator 170 is a preset constant and is a value corresponding to the speed of sound.

In addition, the ultrasonic sensor (S ₁ ), while being scanned in the horizontal direction, based on the time difference from the time of emitting the ultrasonic wave to the time of receiving the ultrasonic wave reflected by the detected object, Since it is configured to detect the distance, the ultrasonic wave is scanned by an angle corresponding to the scanning speed (ω) while receiving the reflected wave of the ultrasonic wave from the time when the ultrasonic wave is emitted. Therefore, an error occurs between the scanning angle at the time of emitting the and the scanning angle at the time of receiving the reflected ultrasonic waves.

As the detection distance (l) increases, the time difference between transmission and reception increases, and the error with respect to the scanning angle at the time of ultrasonic wave emission increases. Therefore, the scanning angle data (θ
The value of n) is corrected according to the size of the detected distance data (ln).

Next, if the absolute value of the difference between the reference distance data (lp) and the next detected distance data (ln _{+ 1} ) is less than or equal to the set value (C) and there is continuity, the continuity is obtained. After performing an averaging process for obtaining the average values (lm) and (θm) of the detection distance data (ln) and the scanning angle data (θn), respectively, a flag (conti flag) indicating data continuity is set to true ( true)
Then, the number of data (n) is updated.

On the other hand, if the absolute value of the difference between the reference distance data (lp) and the next detected distance data (ln _{+ 1} ) is not less than the set value (C), the flag (conti flag) is true ( Based on whether it is true or false, it is determined whether or not continuous data is detected. If continuous data is present, the average value (lm), (θm) of the data is determined. Based on the distance (Xm) in the X-axis direction along the lateral direction of the machine body and the distance (Ym) in the Y-axis direction along the machine body longitudinal direction with respect to the position where the mounting position of the ultrasonic sensor (S ₁ ) is the origin. Each of them is calculated from the following equations (iii) and (iv).

Xm = lm · cos θm …… (iii) Ym = lm · sin θm …… (iv) Then, the distance information (Xm, Ym) obtained by the above equations (iii) and (iv) is used as the second array (Dm). It is stored in the state that it is rearranged.

In other words, except discontinuous data from the detected distance data,
By averaging a plurality of continuous data, it is converted into position information representative of the position of each uncut culm (H) located at a distance.

After storing the obtained distance information (Xm, Ym) in the second array (Dm), the value of the number of data (m) is the maximum value (K).
Update after setting to.

However, when the flag (conti flag) is not true, the value of the reference distance data (lp) is updated to the value of the next detected distance data (ln _{+ 1} ).

After updating the number of data (m), or by changing the value of the reference distance data (lp) to the next detected distance data (l _{n + 1} ).
After updating to the value of, the flag (conti flag) is set to false corresponding to the discontinuous state, and then the process returns to the process of updating the number of data (n) of the first array (Dn). Let

After updating the number (n) of the detection data, it is determined whether or not the value has reached the set number (N). If the value has not reached the set number, the reference distance data (lp) Then, each process after the process of determining whether or not the absolute value of the difference between the detected distance data (ln _{+ 1} ) is less than or equal to the set value (C) is repeated.

When the set number (N) is reached, an approximate straight line connecting the positions corresponding to the stored information is calculated based on the distance information (Xm, Ym) stored in the second array (Dm).

In addition, after initializing the value of the number of data (m) of the second array (Dm) to 1, it is sequentially updated until the value of the number of data (m) reaches the maximum value (K). However, the approximate straight line (f (x) = ax + b) (see FIG. 1) connecting the positions corresponding to the respective average distance data (Xm, Ym) stored in the second array (Dm) is calculated by the least squares method. It is calculated using.

That is, based on the average position information of the continuous distance data stored in the second array (Dm), the approximate straight line (fx
The process of obtaining (x)) corresponds to the straight line calculation means (101).

[Another embodiment]

In the above-mentioned embodiment, the linear calculation means (101) calculates the approximate straight line (fx (x)) by using the least square method, but various calculation methods can be applied. However, the specific configuration can be changed in various ways.

Further, in the above-described embodiment, the case where the distance detection is performed in a state where the scanning of the ultrasonic sensor (S ₁ ) and the distance detection interval are asynchronous is illustrated, but, for example, the distance detection is performed every set time. Alternatively, the distance may be detected for each set scanning angle. Further, as the scanning angle range, it is possible to scan up to a range parallel to the X axis along the lateral direction of the machine body, and various changes can be made.

Further, in the above embodiment, the case where the sampling during the scanning of the ultrasonic sensor (S ₁ ) once is determined based on whether or not the sampling number reaches the set number (N) has been exemplified. The sampling start / stop may be controlled based on the scanning angle (θ) detected by the scanning angle detection sensor (S ₂ ). or,
An approximate straight line may be obtained based on distance information detected during one reciprocating scan or a plurality of scans instead of one scan.

Further, in the above-mentioned embodiment, the case where the left and right steering clutch brakes are operated by turning the steering clutch brakes for the set time has been described as an example. However, for example, driving for both the left and right crawler traveling devices (1) is performed. Two hydraulic continuously variable transmissions are provided so that the speed can be changed separately for left and right,
The steering operation may be performed by making a difference between the left and right driving speeds. When steering is performed with a difference in left and right driving speeds, the detected approximate straight line (f
(X)) The inclination (a) and the width (b) in the width direction are adjusted to adjust the magnitude of the difference between the left and right driving speeds to shift the orientation and position of the aircraft (V) with respect to the approximate straight line. The steering angle may be set according to the size of the.

Further, in the above embodiment, the case where the present invention is applied to the device for controlling the steering of the combine is illustrated, but the present invention is
It can be applied to various types of work vehicles, and the specific configuration of each part can be variously changed.

By the way, in the vehicle for fruit and vegetables, fruit and vegetables can be used as a work target. Further, in a work vehicle or the like that sprays chemicals while traveling along a fruit tree, the fruit tree can be used as a work target.

When the traveling device of the work vehicle is a wheel, for example, the front and rear wheels are individually configured to be steerable, and the inclination (a) with respect to the approximate straight line (f (x)) is corrected by the front and rear wheels. The wheels are steered in opposite phases, and the position (b) in the width direction with respect to the approximate straight line (f (x)) is corrected by the parallel steering method in which the front and rear wheels are steered in phase. You may allow it.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 shows an embodiment of a steering control information detecting device for a work vehicle according to the present invention. FIG. 1 is a block diagram showing a control configuration, FIG. 2 is a flowchart of steering control, and FIG. FIG. 4, FIG. 4 is a schematic side view of the combine, FIG. 5 is an enlarged side view of an essential part showing the mounting structure of the distance sensor, and FIG. 6 is a plan view of the same. (S ₁ ) …… Distance sensor, (S ₃ ) …… Speed detection means,
(V) ... Airframe, (v) ... Running speed, (ω) ... Scanning speed, (10) ... Scanning means, (100) ... Sampling means, (101).

Claims (2)

[Claims] 1. A non-contact type distance sensor (S ₁ ) for detecting a distance to a work object lined up in a traveling direction of the machine body (V) in a state in which the non-contact type distance sensor is spaced from the work object in a lateral direction of the machine body. And a scanning means (10) for scanning the distance sensor (S ₁ ) in order to detect the distances to a plurality of work objects located at the front of the machine at least by the distance sensor (S ₁ ) at the mounting position thereof. ) And the detection distance information from the distance sensor (S ₁ ) corresponding to the scanning angle (θ) by the scanning means (10), sampling means (100) for each set interval, and sampling means (100) A straight line calculating means for obtaining an approximate straight line corresponding to the work object row aligned in the machine body traveling direction based on the plurality of distance information sampled by the means (100) and the scanning angle information ( 102) and a steering control information detecting device for a work vehicle. 2. A speed detecting means (S ₃ ) for detecting a traveling speed (v) of the machine body (V) is provided, and the scanning means (10) is provided.
1) is based on the detection information of the speed detecting means (S ₄ ) so that the scanning speed (ω) of the distance sensor (S ₁ ) increases as the traveling speed (v) increases. The steering control information detecting device for a work vehicle according to claim 1, wherein the steering control information detecting device is configured to automatically adjust the speed (ω).