JP2000355957A - Zone restrictive excavation controller for hydraulic shovel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a zone where excavation can not be carried out because of an incontrollable range to the utmost by providing a detection means and a velocity vector operation correction means regarding the position and posture of a front device. SOLUTION: A relation of a distance D1 between the boundary of a preset zone and the extremity of a bucket 1c and a deceleration vector coefficient h is operated and stored in a memory. When the distance D1 is larger than the distance YAl, the deceleration vector coefficient h=0, when the distance D1 is smaller than the distance YAl, as the distance D1 decreases, the deceleration vector coefficient h increases. The deceleration vector coefficient h is multiplied by a component Vcy of Ya-axis of a target velocity vector Vc and further multiplied by -1 to obtain a deceleration vector VR and the deceleration vector VR is added to the component Vcy. In this way, the target velocity vector Vc is corrected to have a target velocity vector Vca. That is, a ratio reducing a vector component in the direction of approaching the boundary of the preset zone of a target velocity vector of the front device in accordance with a distance between the boundary of the preset zone and the extremity of the bucket varies. And hence, a zone where excavation is not carried out because of incontrollable range is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavation control apparatus for limiting the area of a construction machine, and more particularly, to excavation in which an area in which a front apparatus can move is limited in a construction machine such as a hydraulic shovel having an articulated front apparatus. The present invention relates to an area limited excavation control device and a recording medium on which a control program of the control device is recorded.

[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 device. However, since these front members are connected by joints and rotate.
Excavating a predetermined area by operating these front members is a very difficult task. Therefore, an area-limited excavation control device for facilitating such an operation has been proposed in International Publication WO95 / 30059. This region-restricted excavation control device prohibits the means for detecting the attitude of the front device, the means for calculating the position of the front device based on a signal from this detection signal, and the region in which the front device can move (set region). Means for setting a boundary with the region, and means for calculating a target speed vector of the front device, wherein the target speed vector is perpendicular to the boundary of the setting region in the target speed vector according to the distance between the front member and the boundary of the setting region. By correcting the target speed vector so as to reduce such components and driving the front device in accordance with the corrected target speed vector, the front device can be moved along the boundary of the set area.

[0003]

However, the above-mentioned invention has the following disadvantages.

[0004] In the region limited excavation control, when the front device is operated toward the boundary of the set region, the target speed vector is corrected so as to gradually reduce the component perpendicular to the boundary of the set region.
In order to drive the front device in accordance with the corrected target speed vector, when control is started from a point somewhat distant from the boundary of the setting region, the front device draws a locus that gradually approaches the boundary of the setting region. Therefore, the area near the intersection of the vertical line that is lowered from the point where the front device starts the control operation (at the time when the arm lever is pulled) to the boundary of the setting region does not pass through, and the region where the excavation is not performed due to the control does not occur. It will always remain. If the control start position is on the boundary of the set area, such an unexcavated area does not remain.

[0005] The area where the excavation is not performed is only necessary for the reason of control when the load is light, but when the load of excavation is large, that is, when hard earth and sand is excavated, the area where the excavation is performed is difficult. The device escapes upward, leaving more area than is theoretically present for control.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic excavator area limiting excavation control device capable of smoothly excavating a desired area by minimizing an area where excavation is not performed.

[0007]

(1) In order to achieve the above-mentioned object, the present invention provides a multi-joint type front device comprising a plurality of vertically rotatable front members; A plurality of hydraulic actuators for respectively driving the front members, a plurality of operating means for instructing the operations of the plurality of front members, and driven in response to operation signals of the plurality of operating means, are supplied to the plurality of hydraulic actuators. A hydraulic excavator having a plurality of hydraulic control valves for controlling the flow rate of pressurized oil, the excavator region limited excavation control device,
(A) detecting means for detecting a state quantity relating to the position and attitude of the front device; (b) first calculating means for calculating the position and attitude of the front device based on a signal from the detecting means; (c) (D) first and second calculations, wherein a second calculation means calculates a target vector of the front device based on a calculation value of the first calculation means and a signal from at least one of the plurality of operation means. Means for inputting the calculated value of the means, and when the front device is in the vicinity of the boundary in the preset setting area, the target speed is reduced so as to reduce a vector component of the target speed vector in the direction approaching the boundary of the setting area. A third calculating means for correcting the vector; and (e) control means for controlling a corresponding hydraulic control valve so that the front device moves according to the target speed vector. (F) detecting means for detecting the start of the excavation work by the area-limited excavation control; and (g) detecting the start of the excavation work by the area-limited excavation control by the detection means. According to the distance between the front device and the boundary of the setting area,
Speed vector subtraction correction means for correcting the ratio of reducing the vector component of the target speed vector in the direction approaching the boundary of the set area in the third calculation means.

By providing the detecting means and the speed vector subtraction correcting means as described above, if the distance from the boundary of the set area of the front apparatus at the time when the excavation work by the area limited excavation control is started is sufficiently large, the same as the conventional case. It becomes a trajectory in which the front device gradually approaches the boundary of the setting area, but as the digging progresses, the distance from the boundary of the setting area of the front device at the time of starting the area limit excavation control becomes smaller, Accordingly, the rate of reduction of the vector component of the target speed vector in the direction approaching the boundary of the set area changes, and as a result, the front device reaches far from the boundary of the set area, In addition, since excavation power can be secured, the area where excavation is not performed is reduced in control, and excavation of the desired area can be performed smoothly. It made.

(2) In the above (1), preferably, one of the front members is an arm, and the detecting means detects the start of the cloud operation of the arm.

[0010] In this way, when the area-limited excavation control can be performed by performing the arm cloud operation, the start of excavation work by the area-limited excavation control can be detected.

(3) Further, in the above (1) or (2), preferably, the speed vector subtraction correction means is configured to detect the start of the excavation work by the area-limited excavation control by the detection means. It is assumed that the smaller the distance from the set area, the smaller the ratio of the reduction of the vector component of the target speed vector in the direction approaching the boundary of the set area.

Thus, in the above-described area-limited excavation control, when the distance from the boundary of the set area of the front device at the time of starting the area-limited excavation control (arm cloud operation start time) becomes smaller as the digging proceeds,
The rate of reduction of the vector component of the target velocity vector in the direction approaching the boundary of the set area decreases, that is, the vector component in the direction approaching the boundary of the original set area before being corrected by the third calculation means. Is corrected so as to be close to the target velocity vector having a large value, so that a region where excavation is not performed is reduced due to control, and excavation of a desired region can be performed smoothly.

(4) In order to achieve the above object,
The present invention provides a multi-joint type front device, a plurality of front members rotatable in a vertical direction, a plurality of hydraulic actuators respectively driving the plurality of front members, and an instruction for operation of the plurality of front members. A hydraulic excavator comprising: a plurality of operating means for performing the operation; 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. A program for performing a region-limited excavation control by the computer, the program causing the computer to: (a) calculate a position and a posture of the front device based on a signal from a detection unit;
Calculating means; (b) second calculating means for calculating a target vector of the front device based on a calculated value of the first calculating means and a signal from at least one of the plurality of operating means; When the first and second calculation means input the calculation values and the front device is in the vicinity of the boundary within the preset setting region, the vector component of the target speed vector in the direction approaching the boundary of the setting region is reduced. (D) control means for controlling the corresponding hydraulic control valve so that the front device moves according to the target speed vector, and (e) the area-limited excavation control. Detecting means for detecting the start of the excavation work by means of (e), and (f) installing the front device at the time when the start of the excavation work by the area-limited excavation control is detected by the detection means. In accordance with the distance from the boundary of the area, the third calculation means functions as a speed vector subtraction correction means for correcting the ratio of reducing the vector component of the target speed vector in the direction approaching the boundary of the set area. .

By constructing an area-limited excavation control device using such a recording medium, the above-mentioned area-limited excavation control device (1) can be obtained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hydraulic excavator will be described below 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, 3f, and a plurality of operating lever devices 4a-4 provided corresponding to each of the hydraulic actuators 3a-3f.
f, and controlled by the hydraulic actuators 3a-3
a plurality of flow control valves 5a to 5f for controlling the flow rate of the pressure oil supplied to the hydraulic pump 2 and a relief valve 6 that opens when the pressure between the hydraulic pump 2 and the flow control valves 5a to 5f becomes equal to or higher than a set value.
And these constitute a hydraulic drive device for driving a driven member of the hydraulic shovel.

In this embodiment, the operation lever devices 4a to 4
f is an electric lever device that outputs an electric signal as an operation signal, and the flow control valves 5a to 5f are electro-hydraulic operation systems provided at both ends with electro-hydraulic conversion means for converting the electric signal into pilot pressure, for example, a proportional solenoid valve. The valve.

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 vertically, an upper revolving unit 1d, and a lower traveling unit 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, a driven device driven by a bucket cylinder 3c, a turning motor 3d, and left and right traveling motors 3e and 3f, respectively, and their operations are performed by the operation lever device 4a.
Drive instructions are given by .about.4f.

The hydraulic excavator as described above is provided with the region limited excavation control device according to the present embodiment. The control device includes a setting device 7 for instructing setting of a predetermined portion of the front device, for example, an excavation region in which the tip of the bucket 1c can move in accordance with the work, and respective pivot points of the boom 1a, the arm 1b, and the bucket 1c. Angle detectors 8a, 8b, 8c for detecting respective rotation angles as state quantities relating to the position and orientation of the front device 1A, and a setting device 7
, A control unit 9 for setting an excavation area in which the tip of the bucket 1c can move and for correcting an operation signal. Hereinafter, the set excavation area is particularly referred to as “set area”.

The setting unit 7 outputs a control start or setting signal to the control unit 9 by operating means such as a switch provided on an operation panel or a grip to instruct the control unit 9 to start control or set a setting area. And a setting switch,
For example, a direct teach switch 7a and an area limit start switch 7b are provided. Other auxiliary means such as a display device may be provided on the operation panel.

In this embodiment, the setting device 7 is used to set the setting area, and the control is started when the operation lever of the operation lever device 4b for the arm (hereinafter, appropriately referred to as the arm operation lever) is neutral. The distance D _1S between the bucket tip position at that time and the set value of the set area (described later)
Is calculated and updated. The control is started when the arm operating lever is operated from the neutral position, and the control is ended when the arm operating lever returns to the neutral position.

FIG. 3 shows the configuration of the control unit 9. The control unit 9 is configured by a microcomputer and includes an input unit 91, a central processing unit (CPU) 92, a read-only memory (ROM) 93, a random access memory (RAM) 94, and an output unit 95. I have. The input unit 91 includes operation signals from the operation lever devices 4a to 4f, instruction signals (direct teach switch signal and area limit start switch signal) from the setting device 7, and angle detectors 8a, 8
The signals from b and 8c are input and A / D conversion is performed. RO
M93 is a recording medium in which a control program (described later) is stored. The CPU 92 performs a predetermined calculation process on a signal taken in from the input unit 91 in accordance with the control program stored in the ROM 93. The RAM 94 temporarily stores numerical values during the operation. The output unit 95 creates an output signal according to the calculation result of the CPU 92, and outputs the signal to the flow control valves 5a to 5a.
The signal is output to f.

FIG. 4 is a functional block diagram showing an outline of the control program stored in the ROM 93 of the control unit 9.
The control unit 9 has an area setting unit 97 and an excavation control unit 98. The region setting section 97 performs a setting calculation of a setting region in which the tip of the bucket 1c can move in accordance with an instruction from the direct teach switch 7a of the setting device 7. Excavation control unit 9
At 8, the area limit start switch 7b of the setting unit 7 is turned off.
In the case of (normal mode), the operation signals from the operation lever devices 4a to 4f are output as they are, and in the case of ON (control mode), the signals from the arm operation lever devices 4b are corrected and output to perform area-limited excavation control. . An example of the setting in the area setting unit 97 will be described with reference to FIG. In the present embodiment, a setting area is set in a vertical plane parallel to the X axis.

First, the setting area is set as an initial value to a value deep enough that the front member 1A cannot reach. Because the area limit start switch of the setting unit 7 is set to O
If the area restriction becomes effective from the time of setting N, then the front member 1A can freely move within a operable range and the setting area can be set freely within the operable range.
This is because the initial value of the setting area must be initially set far below the stationary position of the excavator so that the front member 1A does not pass. Here, as an example, the initial value of the straight line equation at the boundary of the setting area is Y = −20.
m.

Next, in FIG. 5, after moving the tip of the bucket 1c to the position of the point P ₁ in the operation of the operator, calculates the tip position of the bucket 1c at that time by pressing the direct teaching switch 7a of the setting device 7 .

The control unit 9 stores the dimensions of each part of the front apparatus 1A and the vehicle body 1B, and the area setting section 97 stores these data and the rotation angles α, β, detected by the angle detectors 8a, 8b, 8c. to calculate the position of P ₁ by using the value of gamma. Position at this time P ₁ is determined as for example the coordinate value of the XY coordinate system with the origin at the pivot point of the boom _{1a (X 1, Y 1)} . The XY coordinate system is a rectangular coordinate system fixed to the main body 1B, and is assumed to be in a vertical plane. XY from rotation angles α, β, γ
The coordinate values (X ₁ , Y ₁ ) of the coordinate system are represented by the distance L ₁ between the pivot point of the boom 1a and the pivot point of the arm 1b, and the distance between the pivot point of the arm 1b and the pivot point of the bucket 1c. L ₂ , the distance between the pivot of the bucket 1c and the tip of the bucket 1c is L
If it is ₃ , it can be obtained from the following equation.

X ₁ = L ₁ sin α + L ₂ sin (α + β) + L ₃ sin (α + β + γ) (1) Y ₁ = L ₁ cos α + L ₂ cos (α + β) + L ₃ cos (α + β + γ) (2) Region of control unit 9 the setting unit 97, from the Y-coordinate values of P ₁ on the boundary of the set area, to calculate the linear equation of the set area to the following calculation equation.

Y = Y ₁ (3) With respect to the area set as described above (hereinafter, appropriately referred to as a set area), the excavation control section 98 of the control unit 9 uses the flowchart shown in FIG. Is performed to limit. Hereinafter, the operation of the present embodiment will be described while clarifying the control function of the excavation control unit 98 with reference to the flowchart shown in FIG.

First, in step 100, an initial value of a distance D _1S (described later) between the bucket tip immediately before the start of the control operation and the set area is set.

Next, in step 110, the ON / OFF of the area limit start switch 7b of the setting device 7 is determined.

If it is determined that the switch 7b is OFF, the operation signal input from the operation lever devices 4a to 4f is output as it is in step 240 without performing the area limiting excavation control in step 125. , And return to START.

On the other hand, if it is determined that the switch 7b is ON, then in step 120, the operation lever device 4 is turned on.
The operation signals of a to 4f are input, and in step 130, the booms 1a, booms 1a,
The rotation angles α, β, and γ of the arm 1b and the bucket 1c are input.

Next, in step 140, the position and orientation of the front device 1A are calculated based on the detected rotation angles α, β, and γ and the dimensions of each part of the front device 1A that have been input in advance. , For example, the tip position of the bucket 1c is calculated. The calculation at this time is
This is the same as the calculation of the bucket tip position in the previous region setting section 97, and in this case also, the bucket tip position is obtained as a value in the XY coordinate system.

Next, in step 150, it is determined whether or not the arm cloud operation is performed by always detecting the operation of the operation lever device 4b corresponding to the arm operation among the operation lever devices 4a to 4f. If not, proceed to step 160.

In step 160, the distance D _1S between the tip of the bucket and the set area when the arm cloud is not operated is calculated.

[0036] Procedure according to 170 in D _1S, distance D between the tip of the boundary and the bucket 1c of the set area as shown in FIG. 8
The relationship between ₁ and the deceleration vector coefficient h is calculated. The relationship between the distance D ₁ and the coefficient h when the distance D ₁ is greater than Y _a1 is a start region of the deceleration control for the boundary of the set area is h = 0, the D ₁ is smaller than Y _a1 , Distance D ₁
Decreases, the deceleration vector coefficient h increases,
The distance D ₁ = 0 and h = 1 are set. Further, D _1S is the curve gradually representing a relationship D ₁ and h the D _1S decreases as shown in FIG. 8 is changed to C ₁₁ → C ₁₂ → C ₁₃ with respect to the relationship between the D ₁ and h, D It is set to change to a curve in which the value of h for ₁ becomes smaller. That is, as shown in FIG. 8, the relationship characteristics between the distance D ₁ to the boundary and the deceleration vector coefficient h are (0, 1) and (Y _a1 ,
0) D _1S from linear C ₁₁ connecting is calculated and set to be a curve C _13, such as closer to the origin (0,0) with decreasing. Therefore, when D _1S is small (when the control operation is started at a position close to the set area), the procedure 12
The velocity vector is corrected so as to be a vector close to the original velocity vector at the tip of the bucket input at 0 (described later).

Here, since the description of the procedures 150 to 170 is made so that the area limited excavation control is started only when the arm cloud operation is performed, D _1S is always performed when the arm cloud operation is not performed. calculates the arm crowding operation have been if just prior to the operation set relationship D ₁ and h (is intended to vary with D _1S, characteristic curve relationship D ₁ pair h as shown as an example in FIG. 8) Is used for control calculation (described later).

Next, in step 180, the front device 1
The target speed vector Vc at the tip of the bucket 1c, which is instructed by the operation signals of the A operation lever devices 4a to 4c, is calculated. Here, 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 the storage device of the control unit 9 in advance, and the operation lever device 4a 4c, the supply flow rates of the corresponding flow control valves 5a to 5c are determined from the operation signals, and the target drive speeds of the hydraulic cylinders 3a to 3c are determined from the values of the supply flow rates. The target speed vector Vc at the tip of the bucket is calculated using the rotation angles α, β, and γ. Then, the vector component Vc in the direction parallel to the boundary of the set area of the target speed vector Vc
A vector component Vcy in a direction perpendicular to x is obtained. Here, the X coordinate component Vcx of the target speed vector Vc is a vector component in a direction parallel to the boundary of the setting area of the target speed vector Vc, and the Y coordinate component Vcy is the target speed vector Vc.
It becomes a vector component in the direction perpendicular to the boundary of the set area of c.

Next, in step 190, it is determined whether or not the tip of the bucket 1c is in the deceleration area which is the area near the boundary in the set area as shown in FIG. In some cases, the procedure proceeds to step 200, in which the target speed vector Vc is corrected so as to decelerate the front device 1A, and then the procedure proceeds to step 210. If not, the procedure directly proceeds to step 210.

Next, in step 210, it is determined whether or not the tip of the bucket 1c is outside the set area as shown in FIG. 7 set as described above. After correcting the target speed vector Vc so that the tip of the bucket 1c returns to the set area, the procedure proceeds to step 230, and if not, the procedure directly proceeds to step 230.

Next, in step 230, the operation signals of the flow control valves 5a to 5c corresponding to the corrected target speed vector Vca obtained in step 200 or 220 are calculated. This is an inverse operation of the calculation of the target speed vector Vc in the procedure 180.

Next, in step 240, the operation signal input in step 120 or the operation signal calculated in step 230 is output, and the process returns to START.

To end the area limit excavation control, press the area limit start switch 7b of the setting unit 7 again to
Turn off. At this time, the linear equation of the setting area stored in the control unit 9 as the setting area until then is reset to the initial value Y = −20 m.

Here, the determination of whether or not the vehicle is in the deceleration area in step 190 and the correction of the operation signal in the deceleration area in step 200 will be described with reference to FIGS.

Step 17 is stored in the storage device of the control unit 9.
0 Relationship (D ₁ pair h characteristic curve relationship that varies D _1S) between a distance D ₁ and the deceleration vector coefficient h between the tip of the boundary and the bucket 1c of the set area as shown in FIG. 8 based on the calculation and It is remembered. Deceleration vector according to the relationship between the distance D ₁ and the coefficient h when the distance D ₁ is greater than the distance Y _a1 is h = 0, the D ₁ is smaller than the Y _a1, the distance D ₁ is decreased The coefficient h increases and the distance D ₁ =
0 is set so that h = 1. In step 190, it is determined that the distance D ₁ of the boundary of the set area and the tip position of the bucket 1c obtained in Step 140 is invaded a deceleration area is smaller than the distance Y _a1. The distance D ₂ between the boundary of the set area and the tip position of the bucket 1c calculated, it is determined that the value of this distance is penetrated Besides setting area When a negative value.

In step 200, the vector component in the direction (vertical direction) approaching the boundary of the set area of the target velocity vector Vc at the tip of the bucket 1c calculated in step 180, that is, the component Vcy of the Y coordinate in the XY coordinate system Is corrected to reduce the target speed vector Vc. Specifically, calculates the deceleration vector coefficient h corresponding from the relationship shown in FIG. 8 stored in the storage device at a distance D ₁ of the the tip of the boundary and the bucket 1c of the set area at that time, the deceleration vector coefficient h The deceleration vector V _R (= −hVcy) is obtained by multiplying the component of the Ya coordinate (vertical vector component) Vcy of the target speed vector Vc by −1, and adding V _R to Vcy. Here, the deceleration vector V _R bucket 1
Its absolute value in accordance with the distance D ₁ of the boundary of c tip and setting area is smaller than the Y _a1 is increased, D the tip of the final bucket 1c reaches the boundary of the set area ₁ =
At the time of 0 coincides with the opposite direction of the velocity vector of Vcy such V _R = -Vcy. Therefore, the deceleration vector V _R
Is the vertical vector component Vc of the target speed vector Vc.
by adding to y, the distance D ₁ is the vector component Vcy to be greater the subtraction correction amount vector component Vcy in the vertical direction is reduced in accordance smaller than Y _a1,
The target speed vector Vc is corrected to the target speed vector Vca.

FIG. 9 shows an example of a trajectory when the tip of the bucket 1c is controlled to decelerate according to the corrected target speed vector Vca as described above. In accordance with the target speed vector Vc is at a constant obliquely downward, the horizontal component Vcx becomes constant, according to the tip of the vertical component Vcy bucket 1c approaches the boundary of the set area (distance D ₁ is less than Y _a1 ) Its absolute value becomes smaller. Since the corrected target speed vector Vca is a composite thereof,
The trajectory has a curved shape that becomes parallel as it approaches the boundary of the set area as shown in FIG. Also, when D ₁ = 0, h = 1, V _R =
Since −Vcy is obtained, the corrected target speed vector Vca on the boundary of the set area matches the horizontal component Vcx.

As described above, in the deceleration control in the procedure 200, the movement of the tip of the bucket 1c in the direction approaching the boundary of the set area is decelerated, and as a result, the moving direction of the tip of the bucket 1c moves to the boundary of the set area. In this sense, the deceleration control in the procedure 200 can also be called direction change control.

FIG. 10 shows an example of a change in the trajectory of the bucket tip when digging is performed. Here, it is assumed that the operation amount of the arm cloud is always constant. First, when the arm cloud operation is started from the boundary surface of the deceleration area in the first excavation, the excavation trajectory becomes _Tr1 by the deceleration control in the procedure 200.

Next, the start of the arm crowding operation from the top P ₁ point of drilling surface remaining in the bucket tip first round of drilling 2
If the first excavation is performed, the excavation trajectory becomes _Tr2 since _D1S < _Ya1 and h is smaller than the first excavation in step 170. Also it begins to arm crowding operation of the same P ₂ points, drilling trajectory and it is assumed that the drilling third is as T _r3. As the digging is repeated, the digging surface gradually approaches a desired digging surface.

Meanwhile, when it relationship between the distance D ₁ of the the tip of the boundary and the bucket 1c for setting as in the conventional region and deceleration vector coefficient h is constant, even if the drilling times on theory follows the same trajectory T _r1 The desired excavation surface is not approached as compared to the arrangement according to the invention. Therefore, in order to excavate an area where excavation is not performed, it is necessary to release the control once and excavate manually.

In actual excavation, in the second excavation, it is extremely rare that the arm cloud operation is started exactly from the point P ₁ , and the tip of the bucket 1 c penetrates into the ground to reach the point P ₁ ′. Usually, the control operation is started (arm cloud operation is started). Even in such a case, T _r1 tip of the bucket 1c is in the form similar T _r1 '
Not this it follows a trajectory, for example, P ₁ becomes able to follow the trajectory of the 'points are at the same height as the _point P, T _r2 in the form similar T _r2 is that is, if the same D _1S' .

The correction of the operation signal outside the set area in step 220 will be described with reference to FIGS.

[0054] The storage device of the control unit 9, the absolute value of the distance D ₂ between the tip of the boundary and the bucket 1c of the set area as shown in FIG. 11 (D ₂ confidence value here is always negative) and recovery The relationship with the vector AR is stored. This distance D ₂
The relationship between the absolute value and the restoration vector AR is the original Y-coordinate is set in a direction upwardly increasing assumption (see FIG. 5) that the absolute value of the distance D ₂ is reduced (of the set area The restoration vector AR is also set so as to decrease as the distance approaches the boundary. In step 220, step 18
Target speed vector V at the tip of bucket 1c calculated at 0
The target velocity vector Vc is corrected so that the vector component in the vertical direction with respect to the boundary of the setting area of c, that is, the component Vcy of the Y coordinate in the XY coordinate system changes to the vertical component in the direction approaching the boundary of the setting area. More specifically, a horizontal component Vcx is added by adding a backward vector Acy (= −Vcy) of Vcy so as to cancel the vertical vector component Vcy.
Extract only By this correction, the tip of the bucket 1c is prevented from moving away from the boundary of the set area and further moving outside the set area. And then calculates the restoration vector AR corresponding from the relationship shown in FIG. 11 stored in the storage device to the absolute value of the distance D ₂ between the tip of the boundary and the bucket 1c of the set area at that time, the restoration vector AR It is further added to the vertical vector component Vcy of the target speed vector Vc. Here, since the original Y coordinate is set to increase in the upward direction, the restored vector AR
the absolute value of the distance D ₂ between the boundary c tip and setting area of the velocity vector of the small reverse (in the drawing upward direction) in accordance with decreases. Therefore, the restoration vector A
R is the vector component V in the vertical direction of the target speed vector Vc.
by adding to cy, distance as the absolute value of D ₂ is the vertical vector component Vcy becomes smaller decreases, the target speed vector Vc is modified into a target speed vector Vca.

FIG. 12 shows an example of a trajectory when the tip of the bucket 1c is restored and controlled according to the corrected target speed vector Vca as described above. When the target speed vector Vc is constant obliquely downward, the horizontal component Vcx is constant, also the vertical component since restoration vector AR is proportional to the absolute value of the distance D ₂ is the tip of the bucket 1c approaches the boundary of the set area (As the absolute value of the distance D ₂ decreases). Since the corrected target speed vector Vca is a composite of the corrected target speed vector Vca, the trajectory has a curved shape that becomes parallel as it approaches the boundary of the set area as shown in FIG.

As described above, in the restoration control in step 220, since the tip of the bucket 1c is controlled to return to the set area, a restored area is obtained outside the set area. Also in this restoration control, the movement of the tip of the bucket 1c in the direction approaching the boundary of the setting area is decelerated, and as a result, the moving direction of the tip of the bucket 1c is converted to a direction along the boundary of the setting area. In this sense, this restoration control can also be called direction change control.

The details of the area limited excavation control device of the present invention are not limited to the above-described embodiment, and various modifications are possible. As an example, in the above embodiment, the relationship characteristic between the distance D ₁ to the boundary and the deceleration vector coefficient h is represented by a straight line C (0, 1) and (Y _a1 , 0) on the coordinates as shown in FIG.
Whereas the calculation-setting so that the curve C _13, such as closer to the origin (0,0) as D _1S decreases from _11, C ₂₁ → C ₂₂ in accordance with D _1S decreases as shown in FIG. 13 →
Changing the C _23, the values of the horizontal axis intercept of the straight line may be calculated and set to change so as to decrease, the same operation and effect in this obtained.

In the above embodiment, the operating lever device is of the electric lever type in the hardware configuration, but may be a hydraulic pilot type operating lever device. Further, although a goniometer for detecting a rotation angle is used as a means for detecting a state quantity relating to the position and orientation of the front device 1A, a stroke of a cylinder may be detected.

[0059]

According to the present invention, if the distance from the boundary of the set area of the front apparatus at the time when the excavation work by the area limited excavation control is started is sufficiently large, the front apparatus is gradually set as in the conventional case. Although it becomes a trajectory approaching the boundary of the area, as the distance from the boundary of the set area of the front device at the time of starting the area limited excavation control becomes smaller as the digging proceeds, the target speed vector Since the ratio of reducing the vector component in the direction approaching the boundary of the setting area changes, as a result, the front device can reach far from the boundary of the setting area, and the excavation force can be secured, so the control is performed. The area where the upper excavation is not performed is reduced, and the excavation of the desired area can be performed smoothly.

[Brief description of the drawings]

FIG. 1 is a diagram showing an area limiting excavation control device of a construction machine according to an embodiment of the present invention together with its hydraulic drive device.

FIG. 2 is a diagram illustrating an external appearance of a hydraulic shovel to which the present embodiment is applied and a shape of a setting area around the hydraulic shovel.

FIG. 3 is a diagram showing a hardware configuration of a control unit.

FIG. 4 is a functional block diagram illustrating processing functions of a control unit.

FIG. 5 is a diagram illustrating a method of setting a coordinate system and an area used in the area restriction control according to the embodiment.

FIG. 6 is a flowchart showing control means in the control unit.

FIG. 7 is a diagram illustrating a relationship between a distance between a tip of a bucket and a boundary of a setting area and a deceleration vector.

FIG. 8 is a diagram illustrating a method of correcting a target speed vector in a deceleration area and a restoration area according to the present embodiment.

FIG. 9 is a diagram illustrating an example of a trajectory when the tip of a bucket is decelerated as corrected.

FIG. 10 is a diagram illustrating an example of a trajectory when deceleration control is performed as corrected when an excavation operation is performed while shifting the position of the tip of a bucket at the start of control.

FIG. 11 is a diagram illustrating a relationship between a distance between a tip of a bucket and a boundary of a setting area and a restoration vector.

FIG. 12 is a diagram illustrating an example of a trajectory when the tip of a bucket is controlled to be restored as corrected.

FIG. 13 is a diagram illustrating a modification of the relationship between the distance between the tip of the bucket and the boundary of the setting area and the deceleration vector.

[Explanation of symbols]

 Reference Signs List 1A Front device 1B Body 1a Boom 1b Arm 1c Bucket 1d Upper revolving structure 1e Lower traveling structure 2 Hydraulic pump 3a-3f Hydraulic actuator 4a-4f Operating lever device 5a-5f Flow control valve 6 Relief valve 7 Setting device (setting means) 7a Direct teach switch 7b Area limit start switch 8a, 8b, 8c Angle detector 9 Control unit 91 Input unit 92 CPU 93 ROM (recording medium) 94 RAM 95 Output unit 97 Area setting unit 98 Excavation control unit

Claims (4)

[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. An area-limited excavation control device, comprising: (a) detection means for detecting a state quantity relating to the position and attitude of the front device; and (b) calculating the position and attitude of the front device based on a signal from the detection means. (C) an eye of the front device based on an operation value of the first operation means and a signal from at least one of the plurality of operation means. A second calculating means for calculating a vector, and (d) inputting the calculated values of the first and second calculating means and, when the front device is located near a boundary within a preset setting area, the target speed vector A third calculating means for correcting the target speed vector so as to reduce a vector component in a direction approaching the boundary of the set area, and (e) a hydraulic pressure corresponding to the front device to move according to the target speed vector A region excavation control device for a hydraulic shovel, comprising: a control unit for controlling a control valve; (f) a detection unit for detecting a start of excavation work by the region restriction excavation control; and (g) a region restriction excavation by the detection unit. The target speed vector in the third calculating means is determined according to the distance between the front device and the boundary of the set area when the start of the excavation work by the control is detected. The setting area hydraulic shovel area limiting excavation control system, characterized in that it comprises a velocity vector subtraction correction means for correcting the rate of reducing the direction of the vector component approaches the boundary of the. 2. The hydraulic excavator according to claim 1, wherein one of said front members is an arm, and said detecting means detects the start of cloud operation of said arm. Area limited excavation control device. 3. The region limited excavation control device according to claim 1, wherein the speed vector subtraction correction unit includes a control unit configured to detect a start of excavation work by the region limited excavation control by the detection unit. An area limited excavation control device for a hydraulic shovel, wherein a ratio of reducing a vector component of the target speed vector in a direction approaching a boundary of the set area decreases as a distance from the set area decreases. 4. 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 according to operation signals of the plurality of operating means and control a flow rate of hydraulic oil supplied to the plurality of hydraulic actuators. In a recording medium recording a program for causing a computer to perform region-limited excavation control, the program includes: (a) first computing means for computing the position and orientation of the front device based on a signal from a detecting means; b) based on the operation value of the first operation means and a signal from at least one of the plurality of operation means, A second calculating means for calculating a target vector of the front device, (c) inputting the calculated values of the first and second calculating means, and when the front device is in the vicinity of its boundary in a preset setting area, Third calculating means for correcting the target speed vector so as to reduce a vector component of the target speed vector in a direction approaching the boundary of the set area; (d) responding to the front device moving according to the target speed vector Control means for controlling a hydraulic control valve to be activated; (e) detection means for detecting the start of excavation work by the area-limited excavation control; (f) time when the detection means detects the start of excavation work by the area-limited excavation control In accordance with the distance between the front device and the boundary of the set area, the third calculation means sets the target speed vector in the direction approaching the boundary of the set area. A recording medium functioning as speed vector subtraction correction means for correcting a rate at which a vector component is reduced.