JPH10292420A - Excavating locus control device of hydraulic shovel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase excavating accuracy and excavating efficiency by installing a calculation means to correct a target speed vector so that a front device approaches more to a target surface to be excavated in parallel with that surface when a distance between the front device and the surface to be excavated becomes smaller. SOLUTION: A control unit 9 sets a surface to be excavated for which the top end of a bucket is operated by the detection signals from operating lever devices 4a to 4c, setting device 7, and angle detectors 8a to 8c. Also the unit 9 obtains the feed flow of flow control valves 5a to 5c based on the signals from the lever devices 4a to 4c, and calculates the target speed vector at the top end of the bucket from a target drive speed and the dimensions of a front device. In addition, when the bucket is located in a speed vector transforming area, the unit 9 corrects the vector so that the traveling direction of the front device is along the target surface to be excavated, and drives a front member. Then the unit 9 calculates a target invasion angle when a distance between the front device and the target surface to be excavated becomes small so as to correct the vector. Thus the target surface to be excavated can be excavated accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavation trajectory control device for a hydraulic shovel, and more particularly to a target excavation surface to be excavated by a front device, which is set in advance. The present invention relates to an excavation trajectory control device for a hydraulic excavator that moves a bucket in a straight line to perform a straight excavation.

[0002]

2. Description of the Related Art In a hydraulic excavator, an operator operates a front member such as a boom by a manual operation lever. However, since these front members are connected by joints and rotate, the operation of these front members to move the front end (bucket end) of the front member linearly requires skill. It is a very difficult task to accompany. Therefore, various devices for facilitating such operations have been proposed in many cases.

For example, Japanese Patent Publication No. 49-132801 discloses conditions such as a gradient of a target excavation surface, a posture angle of a bucket, and an excavation speed, and a boom, an arm, etc. necessary for performing a straight excavation under those conditions. The `` automatic linear digging excavator of hydraulic excavator '' that calculates the operation amount of each hydraulic cylinder using a sequential arithmetic circuit, controls the movement of each front member using this calculation result as an input signal, and performs automatic operation of linear digging Proposed.

Japanese Patent Application Laid-Open No. 61-220226 proposes a "power shovel position control device" in which the accuracy of straight excavation is improved in addition to the control of the bucket cylinder.

On the other hand, as another control device for controlling the movement of the front device, an area-limited excavation control device is known.
This is to set a non-entry area or a digtable area of the front apparatus in advance and control the movement of the front apparatus so that the bucket does not enter the non-penetrable area or does not go outside the digtable area. It is.

For example, in Japanese Patent Application Laid-Open No. 4-136324, a deceleration area is set before an inaccessible area, and when a part of the front device, for example, a bucket, enters the deceleration area,
The operation signal of the operation lever is reduced to decelerate the front device, and stop when the bucket reaches the boundary of the inaccessible area.

[0007] International Publication WO95 / 30059
In the publication, an excavation area is set, and when a part of the front device, for example, the bucket approaches the boundary of the excavation area, only the movement of the bucket in the direction toward the boundary is reduced, and the bucket moves to the boundary of the excavation area. Upon reaching the bucket, the bucket does not go outside the excavable area but can move along the boundary of the excavable area.

[0008]

SUMMARY OF THE INVENTION The above Japanese Patent Publication No. 49-13 / 1979
According to the conventional apparatus described in JP-A-2801 and JP-A-61-222626, the bucket can be moved linearly. However, when actually applied to excavation work, the following problems occur.

When straight excavation is performed by the conventional excavation trajectory control, in any of the proposals, a bucket is first brought over an excavation surface, and a target excavation surface is set in a straight line based on the position information by direct teaching. Therefore, a part of the target excavation surface must be excavated by a human operation before actually entering the control. However, when the excavation trajectory control is performed in this manner, the operator may inadvertently excavate an area below the target excavation surface where the excavation is not desired due to a human error of the operator, and work such as reworking is required. . That is, the operator must take care not to dig below the target digging surface while digging to the target digging surface, and the time and effort for automatically performing the straight digging will not change. Further, since the operation is manually switched to the target excavation surface and the operation is automatically switched to the target excavation surface, the continuity of the operation is impaired, and the operation becomes complicated.

On the other hand, among the conventional region-limited excavation control described in Japanese Patent Application Laid-Open No. 4-136324, it cannot be used for excavation trajectory control because it stops when the bucket reaches the boundary of the inaccessible region.

[0011] Further, International Publication WO95 / 30059
In the region-limited excavation control described in the publication, when the bucket reaches the boundary of the excavation area, the bucket does not move in the direction perpendicular to the boundary of the excavation area, but can move along the boundary of the excavation area. An operation similar to the excavation trajectory control can be performed. However, since the speed component in the direction perpendicular to the boundary of the excavable area is reduced, the bucket speed moving along the boundary of the excavable area is lower than the command speed of the operation lever.

On the other hand, the purpose of excavation trajectory control is to form a straight excavation surface. Particularly in recent excavation trajectory control, from the viewpoint of improving the efficiency of linear excavation, the excavation trajectory control is performed along the target excavation surface. It is desirable to be able to move a bucket quickly at a desired speed.

An object of the present invention is to provide an excavation trajectory control device for a hydraulic excavator that can excavate a target excavation surface accurately and efficiently by a simple operation.

[0014]

[Means for Solving the Problems]

(1) In order to solve the above problems, the present invention provides a plurality of front members rotatable in a vertical direction that constitute an articulated front device, and a plurality of hydraulic actuators that respectively drive the plurality of front members. A plurality of operating means for instructing the operation of the plurality of front members, and a plurality of hydraulic pressures driven in accordance with operation signals of the plurality of operating means and controlling a flow rate of hydraulic oil supplied to the plurality of hydraulic actuators An excavation trajectory control device for a hydraulic shovel including a control valve, comprising: (a) target excavation surface setting means for setting a target excavation surface to be excavated by the front device;
(B) detecting means for detecting a state quantity relating to the position and attitude of the front device; (c) first calculating means for calculating the position and attitude of the front device based on a signal from the detecting means; (d) (E) second operation means for calculating a target speed vector of the front device based on operation signals from the plurality of operation means and an operation value of the first operation means;
Calculating a distance between the front device and the target digging surface based on a calculation value of the first calculating means, and correcting the target speed vector so as to approach parallel to the target digging surface as the distance decreases. Computing means; and (f) control means for driving a corresponding hydraulic control valve so that the front device moves in accordance with the corrected target speed vector, and (g) the third computing means comprises: The target penetration angle of the front device with respect to the target excavation surface, which becomes smaller as the distance between the device and the target excavation surface becomes smaller, is calculated, and the target speed vector is corrected so as to obtain the target penetration angle.

In the present invention configured as described above,
The third calculation means calculates a distance between the front device and the target excavation surface based on the calculation value of the first calculation means, and corrects the target speed vector so as to approach in parallel with the target excavation surface as the distance decreases. Since the control means drives the corresponding hydraulic control valve so that the front device moves according to the corrected target speed vector, the front device gradually moves in the direction along the target digging surface when approaching the target digging surface. When the vehicle reaches the target excavation surface, it moves on the target excavation surface, and the target excavation surface can be excavated with a simple operation and with high accuracy.

The third calculating means calculates a target intrusion angle which becomes smaller as the distance between the front device and the target excavation surface becomes smaller, and corrects the target speed vector so as to obtain the target intrusion angle. The absolute value of the subsequent target speed vector can be kept the same as the absolute value of the target speed vector before correction, and the front device can be moved at the speed as instructed by the operation means, so that the target excavation surface can be efficiently excavated.

(2) In the above (1), preferably,
The third calculating means sets in advance the relationship between the distance between the front device and the target excavation surface and the target intrusion angle, and calculates the target intrusion angle from the set relationship and the calculated distance.

(3) In the above (1), preferably, when the distance between the front device and the target excavation surface is equal to or more than a predetermined value, the third calculating means preferably sets the target calculated by the second calculating means. Output the velocity vector as it is.

Thus, when the front device approaches the target excavation surface beyond the predetermined distance, the operation direction gradually changes to the direction along the target excavation surface as described in (1) above. Although the surface is excavated, the front device can be moved according to the operation of the operation lever device at a position apart from the target excavation surface, and can be operated in the same manner as the normal operation.

(4) Further, in the above (1), preferably, the third calculating means is configured such that when the front device exceeds the target excavation surface and the distance between the front device and the target excavation surface becomes a negative value. Calculating the target penetration angle of the front device for returning the front device onto the target excavation surface, and correcting the target speed vector so as to obtain the target penetration angle.

Thus, when the front device is controlled to move in the direction along the target excavation surface as described in the above (1), a response delay in control or inertia of the front device causes the target excavation surface to move below the target excavation surface. Even if the vehicle enters the target digging surface, the target speed vector is corrected so that the front device returns to the target digging surface, and the front device can be returned to the target digging surface immediately after entering.

(5) In the above (1) or (4), preferably, the third calculation means corrects only the angle while keeping the absolute value of the target speed vector.

Thus, the absolute value of the target speed vector corrected by the third calculating means is kept the same as the absolute value of the target speed vector before correction, and the front device can be moved at the speed specified by the operating means. it can.

(6) Further, in the above (1), preferably, the third calculating means sets the angle of entry of the target speed vector calculated by the second calculating means into the target excavation surface to be smaller than the target angle of entry. If the target velocity vector is large, the target velocity vector is corrected so as to obtain the target penetration angle.

Thus, the front device can be more smoothly moved along the target excavation surface.

(7) According to another aspect of the present invention, there is provided a multi-joint type front device which includes a plurality of vertically rotatable front members, and a plurality of the front members. A plurality of hydraulic actuators,
A plurality of operating means for instructing the operation of the plurality of front members; and a plurality of hydraulic controls driven in accordance with operation signals of the plurality of operating means to control a flow rate of pressure oil supplied to the plurality of hydraulic actuators In the excavation trajectory control device for a hydraulic excavator provided with a valve, (a) target excavation surface setting means for setting a target excavation surface to be excavated by the front device, and (b) a state relating to the position and attitude of the front device. Detecting means for detecting the amount; (c) first calculating means for calculating the position and orientation of the front device based on the signal from the detecting means; and (d) operating signals from the plurality of operating means and 1 Based on the operation value of the operation means,
(E) calculating a distance between the front device and the target excavation surface based on a calculation value of the first calculation means, and calculating the distance as the distance decreases. Third calculating means for correcting the target speed vector so as to approach parallel to the target excavation surface; and (f) driving a corresponding hydraulic control valve so that the front device moves according to the corrected target speed vector. (G) the third arithmetic means includes a speed component perpendicular to a speed component parallel to the target excavation surface of the front device, which decreases as the distance between the front device and the target excavation surface decreases. Is calculated, and the target speed vector is corrected so as to obtain the target ratio.

In the present invention configured as described above,
As described in (1) above, when the front device approaches the target excavation surface, the moving direction is gradually changed to a direction along the target excavation surface by the functions of the third arithmetic means and the control unit, and the front excavation surface is moved to the target excavation surface. When it reaches, it will move on the target excavation surface,
The target excavation surface can be excavated with a simple operation with high accuracy.

Further, the third calculating means calculates a target ratio of a speed component that becomes smaller as the distance between the front device and the target excavation surface becomes smaller, and corrects the target speed vector so as to obtain this target ratio. The absolute value of the corrected target speed vector can be kept the same as the absolute value of the target speed vector before correction, and the front device can be moved at the speed specified by the operation means, so that the target excavation surface can be efficiently excavated.

(8) In the above (7), preferably,
The third calculating means calculates a ratio of a speed component perpendicular to a speed component parallel to the target excavation surface of the front device when a distance between the front device and the target excavation surface reaches a predetermined value, and this ratio is calculated. The target ratio is calculated from the ratio of the distance and a predetermined value on the basis of.

(9) In the above (7), preferably, the third arithmetic means is calculated by the second arithmetic means when the distance between the front device and the target excavation surface is a predetermined value or more. The target speed vector is output as it is.

Thus, as described in (3) above,
At a position away from the target excavation surface, the front device can be moved according to the operation of the operation lever device, and can be operated in the same manner as the normal operation.

(10) Further, in the above (7), preferably, the third calculating means is configured such that when the front device exceeds the target excavation surface and the distance between the front device and the target excavation surface becomes a negative value. Calculating a target ratio of the speed component for returning the front device to the target excavation surface, and correcting the target speed vector so as to obtain the target ratio.

Thus, as described in the above (4), even if the vehicle enters below the target excavation surface due to a response delay in control or inertia of the front device, the front device returns to the target excavation surface. Thus, the target speed vector is corrected at the same time, and the front device can be returned to the target excavation surface immediately after entering.

(11) In the above (7) or (10), preferably, the third calculating means corrects only the ratio of the speed components while keeping the absolute value of the target speed vector.

Thus, the front device can be moved at the speed as instructed by the operating means, as described in (5) above.

(12) Further, in the above (7), preferably, the third calculating means is a speed component perpendicular to a speed component parallel to the target excavation surface of the target speed vector calculated by the second calculating means. Is larger than the target ratio, the target speed vector is corrected so as to obtain the target ratio.

Thus, the front device can be moved more smoothly along the target excavation surface.

[0038]

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

First, a first embodiment of the present invention will be described with reference to FIGS.

Referring to FIG. 1, a hydraulic shovel to which the present invention is applied includes a hydraulic pump 2, a boom cylinder 3a, an arm cylinder 3b, a bucket cylinder 3c, a swing motor 3d, and a boom cylinder 3a driven by hydraulic oil from the hydraulic pump 2. A plurality of hydraulic actuators including left and right traveling motors 3e and 3f, and a plurality of operating lever devices 4a to 4 provided corresponding to these hydraulic actuators 3a to 3f, respectively.
f, the hydraulic pump 2 and the plurality of hydraulic actuators 3a to
3f, a plurality of flow control valves 5a controlled by operation signals of the operation lever devices 4a to 4f to control the flow rate of pressure oil supplied to the hydraulic actuators 3a to 3f.
And a relief valve 6 that opens when the pressure between the hydraulic pump 2 and the flow control valves 5a to 5f is equal to or higher than a set value, and these are hydraulic drive devices that drive driven members of the hydraulic shovel. Is composed.

In the present embodiment, the operation levers 4a to 4f are electric lever devices that output electric signals as operation signals, and operation signals (electric signals) from the operation levers 4a to 4f are provided.
Is input to the control unit 9 and is converted into an operation signal (electric signal) for driving the flow control valves 5a to 5f. The flow control valves 5a to 5f are electro-hydraulic operation type valves provided with electro-hydraulic conversion means for converting an electric signal from the control unit 9 into pilot pressure, for example, a proportional magnetic valve at both ends.

As shown in FIG. 2, the hydraulic excavator includes a multi-joint type front device 1A including a boom 1a, an arm 1b, and a bucket 1c which rotate in a vertical direction, and an upper turning pair 1d and a lower traveling body 1e. The base end of the boom 1a of the front device 1A is supported by the front part of the upper swing body 1d. The boom 1a, the arm 1b, the bucket 1c, the upper swing body 1d, and the lower traveling body 1e are respectively a boom cylinder 3a, an arm cylinder 3
b, bucket cylinder 3c, swing motor 3d, and left and right traveling motors 3e and 3f, respectively, and their operations are instructed by the operation lever devices 4a to 4f.

The excavator as described above is provided with the excavation trajectory control device according to the present embodiment. The excavation trajectory control device includes a setting device 7 for instructing setting of a target excavation surface on which the tip of the bucket 1c can move, a boom 1a, and an arm 1b.
And angle detectors 8a, 8b, 8c provided at respective pivot points of the bucket 1c and detecting the respective pivot angles as state quantities relating to the position and posture of the front device 1A.
And the control unit 9 described above. The control unit 9 receives the operation signals of the operation lever devices 4a to 4c, the setting signal of the setting device 7, and the detection signals of the angle detectors 8a, 8b, 8c. Flow control valves 5a to 5 as operation signals (electric signals)
Output to 5f.

The setting unit 7 outputs a setting signal to the control unit 9 by operating means such as a switch provided on an operation panel or a grip, and instructs setting of a target excavation surface, and is displayed on the operation panel. There may be other auxiliary means such as devices.

As shown in FIG. 3, the control unit 9 has functions of a target excavation surface setting section 9a and an excavation trajectory control section 9b. In addition, the control unit 9 outputs operation signals from operation lever devices 4d and 4f (not shown) to the flow control valves 5d and 5d.
It also has a function of converting it into an operation signal for driving 5f, but this is a general function and is not shown.

The target excavation surface setting section 9a calculates the target excavation surface on which the tip of the bucket 1c operates in accordance with an instruction from the setting device 7. One example will be described with reference to FIG. In addition,
In this embodiment, a target excavation plane is set in a vertical plane.

[0047] In FIG. 4, after moving the tip of the bucket 1c to the position of the point P ₁ in the operation of the operator, and calculates the tip position of the bucket 1c at that time in response to an instruction from the setting device 7, then setting device 7 the operates by entering the depth h ₁ from its position, specify the P _{1 *} point on the target excavation plane to be set by the depth. Next, after moving the tip of the bucket 1c to the position of the point P _2, to calculate the instruction at the tip position of the bucket 1c at that time from the setting device 7, the depth from that position by operating the same manner setter 7 It is to input h _2, designating a point P _{2 *} on the target excavation plane to be set by the depth. And
A straight line equation connecting the two points P _{1 *} and P _{2 *} is calculated and used as the target excavation surface.

The control unit 9 stores the dimensions of the front device 1A and the body 1B. The target excavation surface setting unit 9a stores these data and the angle detectors 8a, 8b,
Using the values of the rotation angles α, β, and γ detected in 8c, the positions of the two points P ₁ and P ₂ are calculated using the position and posture calculation function of the excavation trajectory control unit 9b.

Here, the positions of the two points P ₁ and P ₂ are, for example, coordinate values (X) of an XY coordinate system having the origin at the pivot point of the boom 1a.
₁ , Y ₁ ) (X ₂ , Y ₂ ). The XY coordinate system is a rectangular coordinate system fixed to the main body 1B, and is assumed to be in a vertical plane.

Further, the coordinate values (X ₁ , Y ₁ ) (X ₂ , Y ₂ ) of the XY coordinate system from the rotation angles α, β, γ are determined by the rotation fulcrum of the boom 1a and the rotation fulcrum of the arm 1b. Distance L ₁ , arm 1
distance L ₂ between the pivot point of b of the pivot point and the bucket 1c, if the distance between the tip of the pivot point and the bucket 1c of the bucket 1c and L _3, determined from the following equation.

X = L ₁ sin α + L ₂ sin (α + β) + L ₃ sin (α + β + γ) (1) Y = L ₁ cos α + L ₂ cos (α + β) + L ₃ cos (α + β + γ) (2) In the target excavation surface setting section 9a , Two points P _{1 *} on the target excavation surface,
The P _{2 *} coordinate value, respectively, the following calculation of the Y _{coordinate, Y 1 * = Y 1 -h} 1 Y 2 * = determined by performing Y ₂ -h _2. Further, a linear equation connecting the two points P _{1 *} and P _{2 *} is calculated by the following equation.

Y = (Y _{2 *} −Y _{1 *} ) X / (X ₂ −X ₁ ) +
(X ₂ Y _{1 *} −X ₁ Y _{2 *} ) / (X ₂ −X ₁ ) Further, an arbitrary point O on a straight line connecting the above two points P _{1 *} and P _{2 *} is set as the origin, and X with the straight line connecting the two points as the X axis
Considering the aYa coordinate system, coordinate conversion data for converting the value of the XY coordinate system to the XaYa coordinate system is obtained. The XaYa coordinate system can be easily obtained from the coordinate values (X ₀ , Y ₀ ) of the point O in the XY coordinate system.

The excavation trajectory control section 9b of the control unit 9 controls the front apparatus 1A to move the front device 1A linearly in accordance with the flowchart shown in FIG. 5 with respect to the target excavation surface set as described above. Hereinafter, while clarifying the control function of the excavation trajectory control unit 9b according to the flowchart shown in FIG.
The operation of the present embodiment will be described.

First, in step 100, operation signals of the operation lever devices 4a to 4c are input, and in step 110, the rotation angles of the boom 1a, the arm 1b, and the bucket 1c detected by the angle detectors 8a, 8b, 8c are determined. input.

Next, in step 120, the position and orientation of the front device 1A are calculated based on the detected rotation angles α, β, γ and the dimensions of the front device 1A stored in the storage device of the control unit 9 in advance. Is performed, and the front device 1A
, For example, the tip position of the bucket 1c is calculated. The calculation at this time is based on the previous target excavation surface setting unit 9a.
In this case as well, the position of the bucket tip is obtained as a value in the XY coordinate system, and further, coordinate conversion data for converting the value in the XY coordinate system into the XaYa coordinate system is obtained in this case. .

Next, in step 130, the target speed vector Vc at the tip of the bucket 1c, which is instructed by the operation signals of the operation lever devices 4a to 4c, is calculated. That is, the relationship between the operation signals of the operation lever devices 4a to 4c and the supply flow rates of the flow control valves 5a to 5c and the dimensions of each part of the front device 1A are stored in a storage device of the control unit 9 in advance, and the operation lever devices 4a to 4c are stored. The flow control valve 5 corresponding to the operation signal of 4c
The supply flow rates of the hydraulic cylinders 3a to 3c are determined from the supply flow rates of the hydraulic cylinders 3a to 3c, and the target speed vector Vc at the tip end of the bucket is calculated using the target drive speed and the dimensions of each part of the front device 1A. I do. Further, the target speed vector Vc is calculated using the XY coordinate system, and then the target speed vector Vc is converted into the speed vector Vca0 in the XaYa coordinate system using the conversion data from the XY coordinate system previously obtained to the YaYa coordinate system. I do.

Next, in step 140, it is determined whether or not the tip of the bucket 1c is located in the speed vector conversion area, which is the area near the target excavation plane as shown in FIG. If it is in the conversion area, the process proceeds to step 150, in which the traveling direction of the front apparatus 1A is corrected to Vca so as to be along the target excavation surface.
Proceed to.

Next, in step 160, the operation signals of the flow control valves 5a to 5c corresponding to the corrected target speed vector Vca obtained in step 150 are calculated. This is done in step 13
This is the inverse operation of the calculation of the target speed vector Vc at 0.

Next, in step 170, the operation signal input in step 100 or the operation signal calculated in step 160 is output to the flow control valves 5a to 5c to control the driving of each front member, and the process returns to the beginning.

Here, the determination as to whether or not the vehicle is in the velocity vector conversion area in step 140 and the correction of the operation signal in step 150 will be further described with reference to FIGS.

The storage device of the control unit 9 stores the distance D1 between the target excavation surface and the tip of the bucket 1c as shown in FIG.
And the target penetration angle θd are stored. The target penetration angle θd is an angle between the target speed vector at the tip of the bucket 1c and the target excavation surface. This distance D1
And the target penetration angle θd, the distance D1 is the distance Ya1
In the above, θd = 90 °, and when the distance D1 becomes smaller than the distance Ya1, the target penetration angle θd decreases as the distance D1 decreases, and θd = 0 ° at the distance D1 = 0, and the distance D1 becomes 0. Below, that is, when the value becomes a negative value, the target penetration angle θd also becomes a negative value, and as the distance D1 decreases, the target penetration angle θd also decreases, and the distance D1 becomes the distance −Y
If it is smaller than a, it is set so that θd = −90 °.

In step 140, the distance D1 between the tip position of the bucket 1c obtained in step 120 and the target excavation plane is calculated.
If the distance D1 is smaller than the distance Ya1, it is determined that the vehicle has entered the velocity vector conversion area. Here, the distance D1 is obtained by converting the position of the front end to the XaYa coordinate system using the above-described conversion data from the XY coordinate system to the XaYa coordinate system, and obtaining the Ya coordinate value thereof.

In step 150, as shown in FIG. 8, a target penetration angle θd corresponding to the distance D1 at that time is obtained from the relationship between the distance D1 and the target penetration angle θd shown in FIG. 7 (step 180). While keeping the absolute value of the speed vector Vca0 as it is, the angle with respect to the target
Vca is determined from the target velocity vector having the target penetration angle θd shown in FIG. Next, the corrected target speed vector Vca is decomposed in the XaYa direction (step 182). The calculation formula to be decomposed is as follows.

Vcax = | Vca | × cos θd (3) Vcay = − | Vca | × sin θd (4) When the tip of the bucket 1c is corrected according to the corrected target speed vector Vca as described above. Fig. 9 shows an example of the trajectory
And FIG. As the tip of the bucket 1c approaches the target digging surface, the target speed vector Vca0 is corrected so as to be parallel to the target digging surface, and Vca is set on the target digging surface.
y = 0, and the tip of the bucket 1c moves parallel to the target excavation surface. If the tip of the bucket 1c comes out of the excavation area beyond the target excavation surface due to a response delay in control or inertia of the front device 1A, the bucket 1
The target speed vector Vca0 is corrected so that the tip of the c returns to the target excavation surface and becomes parallel to the target excavation surface as the tip of the bucket 1c approaches the target excavation surface. Vcay = 0 on the target excavation surface, and the bucket 1c Moves parallel to the target excavation plane.

Next, the calculation of the correction operation signal in step 160 will be described. Differentiating the above equations (1) and (2), XY
If the coordinate system is converted into XaYa coordinates, velocity vectors in the Xa direction and the Ya direction on the XaYa coordinate system can be obtained. In the equations (1) and (2), if the angles α, β, γ on the right side are differentiated, the positions X, Y on the left side are differentiated. That is, the conversion is performed as follows.

(Α ′, β ′, γ ′) → (X ′, Y ′) →
(Vcax, Vcay) "" represents differentiation. Therefore, here, the boom angular velocity α ′ and the arm angular velocity β ′ are obtained from Vcax and Vcay specified by the equations (3) and (4) by the inverse calculation of the above conversion equation.
Note that the bucket angular velocity γ ′ = 0 is set. When the boom angular velocity α ′ and the arm angular velocity β ′ are obtained, the link correction is performed to obtain the boom speed and the arm speed. Therefore, a boom and arm operation command signal corresponding to these values is calculated.

In the present embodiment configured as described above, when the tip of the bucket 1c is separated from the target excavation surface,
Since the target speed vector Vca0 is not corrected, the front device 1A according to the operation signals of the operation lever devices 4a to 4c.
And can be operated in the same way as normal operation,
When the tip of the bucket 1c approaches the target excavation surface, the target speed vector Vca0 is corrected so as to be parallel to the target excavation surface. Therefore, as shown in FIGS. 9 and 10, the tip of the bucket 1c along the target excavation surface. Can be moved. For this reason, the operator operates the operation lever devices 4a to 4c as in a normal excavation, so that the tip of the bucket 1c automatically moves on the target excavation surface. The excavation surface can be excavated.

When the tip of the bucket 1c approaches the target excavation surface, the correction of the target speed vector Vca0 is performed only by correcting the angle between the target excavation surface and the absolute value of the target speed vector Vca0. Therefore, the front device is moved at the speed as instructed by the operation lever device, and it is possible to efficiently excavate the target excavation surface.

In the above embodiment, in FIG. 8, if the target intrusion angle θd corresponding to the distance D1 at that time is obtained from the relationship between the distance D1 and the target intrusion angle θd in step 180, the target intrusion angle is immediately obtained in step 181. Although the target speed vector Vca was obtained using the angle θd, as shown in FIG. 9, the angle θ of the target speed vector Vca0 of the tip of the bucket 1c calculated in step 130 with respect to the target excavation plane is shown in FIG.
(Step 180A), the process proceeds to Step 181 only when θ becomes larger than θd, and the absolute value of the target speed vector Vca0 is kept as it is, and the angle θ with respect to the target excavation surface is changed. Step 18
Vca may be obtained from the target speed vector set to θd obtained at 0. Thereby, the tip of the bucket 1c can be moved more smoothly along the target excavation surface.

FIGS. 12 and 1 show a second embodiment of the present invention.
3 will be described. In the above embodiment, the target speed vector Vca0 is corrected to be parallel to the target excavation plane by changing the angle of the target speed vector Vca0 to the target intrusion angle θd.
The target speed vector Vca0 is corrected so as to be parallel to the target excavation plane by changing the ratio of the vector components of the ca0 in the Xa direction and the Ya direction.

That is, in the present embodiment, of the procedures 100 to 170 of the flowchart shown in FIG. 5, which are the processing contents of the excavation trajectory control section 9b (see FIG. 3) of the control unit 9, the procedure 150 is the procedure shown in FIG. 150A, and the rest is the same as the first embodiment.

Referring to FIG. 12, in a procedure 150A, first, the bucket 1c is stored in the velocity vector conversion area shown in FIG.
The target speed vector Vca0 obtained in step 130 at the time when the tip of the target speed enters is defined as Vca1, and the absolute value | Vca1 | of the target speed vector Vca1 and the vector components Vcax1 and Vcay1 in the Xa and Ya directions are obtained (step 19).
0). Next, the ratio α of Vcax1 and Vcay1 is calculated by α = V
It is obtained as pay1 / Vcax1 (procedure 191).

Next, the target ratio αd of the vector components in the Xa direction and the Ya direction of the corrected target speed vector Vca to be obtained is determined as follows (step 192).

Αd = α × D1 / Ya1 (5) Next, the Xa direction and Ya of the corrected target speed vector Vca
The following equation is established with the ratio of the vector components in the direction as the target ratio αd.

Vcay / Vcax = αd (6) Further, the following calculation is added to keep the absolute value of the target speed vector at | Vca1 |.

(Vcax) ² + (Vcay) ² = | Vca1 | ² (7) Vcax and Vcay are obtained from the above equations (6) and (7) (step 193). At this time, two combinations of Vcax and Vcay are obtained.

Next, it is determined whether or not the distance D1 is equal to or greater than 0, that is, whether or not the tip of the bucket 1c has moved beyond the target excavation surface and outside the target excavation surface.
As shown in FIG. 3, a combination in which Vcay is a negative value is selected from two combinations of Vcax and Vcay, and
cax, Vcay are determined (procedures 194, 195).
Also, if the tip of the bucket 1c is outside the target excavation plane, V out of two combinations of V cax and V cay
A combination in which Cay has a positive value is selected, and Vcax,
Vcay is determined (procedures 194 and 196).

The trajectory when the tip of the bucket 1c is corrected according to the corrected target speed vector Vca as described above is the same as that described with reference to FIGS. 9 and 10 in the first embodiment. is there. That is, as the tip of the bucket 1c approaches the target excavation surface, the target speed vector Vca0 is corrected so as to be parallel to the target excavation surface, and Vcay = 0 on the target excavation surface. Move in parallel. When the tip of the bucket 1c goes outside the excavation area beyond the target excavation surface, the tip of the bucket 1c returns to the target excavation surface and the bucket 1c
The target speed vector Vca0 is corrected so that the tip of the bucket becomes closer to the target excavation surface as it approaches the target excavation surface, Vcay = 0 on the target excavation surface, and the tip of the bucket 1c moves parallel to the target excavation surface. I do.

When the components Vcax and Vcay of the target speed vector Vca are obtained in step 150A, the target boom angular speed and the arm angular speed are calculated as in the first embodiment.

In the present embodiment configured as described above, when the tip of the bucket 1c approaches the target digging surface, the target speed vector Vca0 is corrected so as to be parallel to the target digging surface. Similar to the embodiment, the target excavation surface can be excavated with a simple operation and high accuracy.

The correction of the target speed vector Vca0 when the tip of the bucket 1c approaches the target excavation surface is performed by X
Since the absolute value of the target speed vector Vca0 is maintained only by correcting the ratio of the vector components in the a direction and the Ya direction,
As in the first embodiment, the front device is moved at a speed as instructed by the operation lever device, and can efficiently excavate the target excavation surface.

Note that the present embodiment can be modified in the same manner as the first embodiment. That is, in FIG. 14, after obtaining α = Vcay1 / Vcax1 in step 191, the vector components Vca in the Xa and Ya directions of the target speed vector Vca0 of the bucket 1c calculated in step 130 are obtained.
The ratio α0 of x01 and Vcay01 is expressed as α0 = Vcay01 /
Vcay01 (procedure 191A), and the target ratio αd of the vector components in the Xa and Ya directions of the correction target speed vector Vca to be obtained is obtained from αd = α × D1 / Ya1 in the above equation (5) (procedure 191A). 192),
Next, it is determined whether or not the ratio α0 is larger than the target ratio αd (step 192A).
3 and Vcax,
Find Vcay. Also in this case, the tip of the bucket 1c can be moved more smoothly along the target excavation surface.

Although the embodiments of the excavation trajectory control device of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications are possible. As an example, a goniometer that detects a rotation angle is used as a means for detecting a state quantity related to the position and orientation of the front device 1A, but a stroke of a cylinder may be detected.

The method for setting the target setting surface may be a method other than that of the present embodiment. For example, the depth and the angle may be set using a dial on the operation panel.

[0085]

According to the present invention, when the front device approaches the target excavation surface, the target velocity vector is corrected so as to be parallel to the target excavation surface. The tip of 1c automatically moves on the target excavation surface, and the target excavation surface can be excavated with a simple operation with high accuracy. In addition, since the front device can be moved at the speed as instructed by the operation means, the target excavation surface can be efficiently excavated.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an excavation trajectory control device of a hydraulic shovel according to a first embodiment of the present invention, together with a hydraulic drive device.

FIG. 2 is a diagram showing the appearance of a hydraulic shovel to which the present invention is applied and the shape of a setting area around the hydraulic shovel.

FIG. 3 is a block diagram showing an outline of functions of a control unit.

FIG. 4 is a diagram illustrating a method of setting a coordinate system and a target excavation surface used in excavation trajectory control.

FIG. 5 is a flowchart illustrating a processing procedure of excavation trajectory control.

FIG. 6 is a diagram illustrating a method of correcting a target speed vector in a speed vector conversion area.

FIG. 7 is a diagram illustrating a relationship between a distance between a tip of a bucket and a target excavation surface and a target penetration angle.

FIG. 8 is a diagram showing details of the procedure of the speed vector conversion control shown in FIG. 5;

FIG. 9 is a diagram illustrating an example of a trajectory when a tip of a bucket is controlled in front of a target excavation surface according to a corrected target speed vector.

FIG. 10 is a diagram illustrating an example of a trajectory when the tip of a bucket is controlled according to a corrected target speed vector outside a target excavation surface.

FIG. 11 is a diagram showing a modification of the processing procedure shown in FIG. 8;

FIG. 12 is a flowchart showing a processing procedure of excavation trajectory control of the excavation trajectory control device for a hydraulic shovel according to the second embodiment of the present invention.

FIG. 13 is a diagram illustrating a method of correcting a target speed vector in a speed vector conversion area.

FIG. 14 is a diagram showing a modification of the processing procedure shown in FIG.

[Explanation of symbols]

 Reference Signs List 1A Front device 1B Body 2 Hydraulic pump 3a-3f Hydraulic actuator 4a-4f Operating lever device 5a-5f Flow control valve 7 Setting device 8a, 8b, 8c Angle detector 9 Control unit

Claims (12)

[Claims] 1. A plurality of front members rotatable in a vertical direction constituting a multi-joint type front device, a plurality of hydraulic actuators respectively driving the plurality of front members, and an operation of the plurality of front members. A hydraulic shovel comprising: a plurality of operating means for instructing; and a plurality of hydraulic control valves that are driven in accordance with operation signals of the plurality of operating means and control a flow rate of hydraulic oil supplied to the plurality of hydraulic actuators. In the excavation trajectory control device, (a) target excavation surface setting means for setting a target excavation surface to be excavated by the front device; (b) detection means for detecting state quantities related to the position and orientation of the front device; (C) first calculating means for calculating the position and orientation of the front device based on a signal from the detecting means; and (d) operation signals from the plurality of operating means. Second calculating means for calculating a target speed vector of the front device based on a signal calculated by the first calculating means; and (e) the front device and the target excavation surface based on the calculated value of the first calculating means. A third calculating means for calculating a distance to the target excavation surface as the distance decreases, and correcting the target speed vector so as to approach the target excavation surface in parallel with the distance. (F) According to the corrected target speed vector, Control means for driving a hydraulic control valve corresponding to movement of the front device; and (g) the third arithmetic means is configured to reduce the target excavation surface which decreases as the distance between the front device and the target excavation surface decreases. The excavation trajectory control of a hydraulic shovel, wherein a target penetration angle of the front device with respect to the vehicle is calculated and the target speed vector is corrected so as to obtain the target penetration angle. Apparatus. 2. The excavation trajectory control device for a hydraulic shovel according to claim 1, wherein said third calculating means sets in advance a relationship between a distance between said front device and a target excavation surface and said target penetration angle. An excavation trajectory control device for a hydraulic shovel, wherein a target intrusion angle is calculated from the set relationship and the calculated distance. 3. The excavation trajectory control device for a hydraulic shovel according to claim 1, wherein said third arithmetic means calculates by said second arithmetic means when a distance between said front device and a target excavation surface is a predetermined value or more. An excavation trajectory control device for a hydraulic shovel, wherein the excavation target speed vector is output as it is. 4. The excavation trajectory control device for a hydraulic shovel according to claim 1, wherein the third calculating means is configured to determine that the distance between the front device and the front device exceeds the target excavation surface and the distance between the front device and the target excavation surface is a negative value. Calculate the target penetration angle of the front device to return the front device to the target excavation surface, and correct the target speed vector so as to obtain the target penetration angle. Control device. 5. The excavator trajectory control device for an excavator according to claim 1, wherein said third calculating means corrects only the angle while keeping the absolute value of said target speed vector. Excavation trajectory control device. 6. The excavation trajectory control device for a hydraulic shovel according to claim 1, wherein the third calculating means determines that the angle of entry of the target speed vector calculated by the second calculating means into the target excavation surface is equal to the target intrusion angle. An excavation trajectory control device for a hydraulic shovel, wherein the target speed vector is corrected so as to obtain the target penetration angle when the angle is larger than the angle. 7. A plurality of front members rotatable in a vertical direction constituting a multi-joint type front device, a plurality of hydraulic actuators respectively driving the plurality of front members, and an operation of the plurality of front members. A hydraulic shovel comprising: a plurality of operating means for instructing; and a plurality of hydraulic control valves that are driven in accordance with operation signals of the plurality of operating means and control a flow rate of hydraulic oil supplied to the plurality of hydraulic actuators. In the excavation trajectory control device, (a) target excavation surface setting means for setting a target excavation surface to be excavated by the front device; (b) detection means for detecting state quantities related to the position and orientation of the front device; (C) first calculating means for calculating the position and orientation of the front device based on a signal from the detecting means; and (d) operation signals from the plurality of operating means. Second calculating means for calculating a target speed vector of the front device based on a signal calculated by the first calculating means; and (e) the front device and the target excavation surface based on the calculated value of the first calculating means. A third calculating means for calculating a distance to the target excavation surface as the distance decreases, and correcting the target speed vector so as to approach the target excavation surface in parallel with the distance. (F) According to the corrected target speed vector, Control means for driving a hydraulic control valve corresponding to movement of the front device; and (g) the third calculation means is configured to reduce the distance between the front device and a target excavation surface, the smaller the distance, the smaller the distance between the front device and a target excavation surface. A hydraulic system, comprising: calculating a target ratio of a speed component perpendicular to a speed component parallel to a target excavation surface, and correcting the target speed vector so as to obtain the target ratio. Le drilling trajectory control device. 8. The excavation trajectory control device for a hydraulic shovel according to claim 7, wherein said third arithmetic means is configured to execute a target excavation of the front device when a distance between the front device and the target excavation surface reaches a predetermined value. An excavation trajectory control device for a hydraulic shovel, wherein a ratio of a vertical speed component to a speed component parallel to a plane is calculated, and the target ratio is calculated from the ratio of the distance and a predetermined value based on the ratio. 9. The excavation trajectory control device for a hydraulic excavator according to claim 7, wherein the third arithmetic means is configured to execute the second arithmetic means when a distance between the front device and the target excavation surface is a predetermined value or more. An excavation trajectory control device for a hydraulic shovel, which directly outputs a calculated target speed vector. 10. The excavation trajectory control device for a hydraulic shovel according to claim 7, wherein the third arithmetic means determines that the distance between the front device exceeds the target excavation surface and the distance between the front device and the target excavation surface is a negative value. And calculating a target ratio of the speed component for returning the front device to the target excavation surface, and correcting the target speed vector so as to obtain the target ratio. 11. The excavation trajectory control apparatus for an excavator according to claim 7, wherein said third calculating means corrects only the ratio of the speed components while keeping the absolute value of said target speed vector. Excavation trajectory control device for hydraulic excavators. 12. The excavation trajectory control device for a hydraulic shovel according to claim 7, wherein the third calculating means is perpendicular to a speed component of the target speed vector calculated by the second calculating means which is parallel to the target excavation surface. An excavation trajectory control device for a hydraulic shovel, wherein the target speed vector is corrected so that the target ratio is obtained when the ratio of the speed components is larger than the target ratio.