JP2631757B2 - Excavation control method for construction machinery - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention moves a bucket while keeping a bucket at a fixed height position and posture with respect to a digging surface, such as a slope excavation (finishing) operation and a horizontal extrusion operation. The present invention relates to a hydraulic shovel excavation control method for repeatedly performing excavation work.

2. Description of the Related Art An excavation control method for a hydraulic excavator among construction machines is disclosed in JP-A-64-14430. FIG. 5 is an external view of a hydraulic excavator operated by a conventional excavation control method. In the drawing, 1 is a revolving structure of a hydraulic excavator body, 2 is a boom pivotally mounted on a front portion of the revolving structure 1, 3 is an arm, 4 is a bucket, 5 is a boom cylinder, 6 is an arm cylinder, and O is a boom base end. , A is the end of the boom, B is the end of the arm, θ ₁ is the ground angle of the boom 2 (same as the boom angle), α ₂ is the angle of the arm 3 with respect to the boom 2 (same as the arm angle), and α ₃ is the bucket with respect to the arm 3 Angle 4 (same as bucket angle), β is the digging angle, l ₁ is the distance from the boom base O to the boom tip A (boom length), l ₂ is the distance from the boom tip A to the arm tip (arm length) X) is the horizontal coordinate axis, y is the vertical coordinate axis,
G is the excavation surface. In addition, when the hydraulic excavator performs the slope excavation, the coordinate calculation of the position of the arm tip B is performed on the coordinate axes x ′,
This is performed based on y ′. Next, FIG. 6 is a block diagram of control showing a basic embodiment of a conventional excavation control method. FIG. 7 shows a controller according to an embodiment of the prior art.
It is a functional block diagram of C _0.

Next, a conventional excavation control method will be described with reference to FIGS. 5 and 6. FIG. First, the operation procedure during the excavation operation is as follows.

(A) The operator manually sets the bucket 4 at the excavation start point on the excavation plane G (for example, the solid line position in FIG. 5).

(B) In this state, turn on the initial posture setting switch 15, and
The initial posture is memorized and the digging angle setting switch 13
Sets the target angle β.

(C) Set the automatic / manual switch 14 to the automatic side.

(D) Automatic excavation is started by operating the arm lever, and the bucket 4 is moved in the direction of arrow A in FIG. 5 to perform the first automatic excavation.

(E) Return the arm lever to end the first automatic excavation.

(F) Return the automatic / manual switch 14 to the manual side.

(G) The operator manually returns the bucket 4 to the approximate initial posture.

(H) Set the automatic / manual switch 14 to the automatic side again.

(I) The automatic return switch 16 accurately adjusts the bucket position and posture to the initial posture stored in the above item (b).

(Nu) The second excavation operation is performed by operating the arm lever in the same manner as in the above items (d) and (e).

Hereinafter, the operations of the items (f) to (nu) are repeated to perform the excavation operation repeatedly.

Next, the function of the controller C during the excavation operation will be described with reference to FIG. The controller C includes an arm control block C _1, the boom control block C _2, consists bucket control block C ₃ Prefecture, during each rotational operation in the repeated drilling operations, the control block C ₁ for each of a plurality of time points, C
In _2, C _3, arm boom, the control amounts for the cylinders (6,5,7) of the bucket is determined as follows.

(I) Arm control block C _{1 In} this block C ₁ , the arithmetic lever 20 multiplies an arm lever signal (speed command signal) by the arm lever pilot pressure detector 11 or 12 by a predetermined gain to obtain a basic control amount u. ₂₁ and the arm link correction means 21
To obtain a primary correction control amount u ₂₂ , and to output a secondary correction control amount u ₂ obtained by further correcting the primary correction control amount u ₂ as a control amount to the arm cylinder hydraulic control unit 17. I have to. Arm 3
Is manually controlled at a constant angular velocity according to a command velocity by an arm lever operation.

(II) Boom control block C _{2 In} this block C ₂ , both detectors 8 for boom angle and arm angle are provided at each time during one excavation operation.
9 by the current boom angle theta ₁ and the arm angle alpha ₂ is input, and these angle signal, based on the basic control quantity u ₂₁ of arm control block C _2, the boom cylinder feedforward control unit 23, the arm tip B the height position of (the bucket height position) operation of the boom cylinder feedforward control amount u ₁₁ for keeping the y _b constant is performed.
Also from the boom angle signal and the arm angle signal, the height position y _b of the actual arm tip B is determined by calculation by the coordinate calculator 24. The coordinate axes (x, y) are corrected to coordinate axes x ', y' by a target angle β (not shown), and the input value θ
_{It is} also assumed that ₁ and α ₂ have been corrected to values symmetrical with respect to the coordinate axes x ′ and y ′. Then, from the deviation Δy _b between the calculated value y _b and the target value y _bo of the arm tip height position, the proportional integration means 25
Feedback control amount u ₁₂ is calculated by. Further, the feedback control amount u ₁₂ is inputted to the learning means 26. In this learning unit 26, the feedback control amount u ₁₂ entered over learning gain calculated learned value, this current learned value and the learned value at the previous same time adds to store the sum ( and updates) the learning value, and outputs a previous learned value storage Zumi as the present learning control quantity u _13. Thus while updating the learning value at each time point for each drilling operation, the pre-update of the learning value u _13, the boom cylinder feedforward control amount u _11, in addition to the feedback control amount u ₁₂ obtains the basic control quantity u _14. This basic control amount u _14, corrected by a boom link correcting unit 27 (first
Next correction control amount u _15), corrected by the boom attitude correcting unit 28 (second-order correction control amount u _16), the boom cylinder control output U ₁ by adding the correction by the nonlinear compensation unit 28 is determined. Since the control accuracy is improved each time the excavation operation is repeated as described above, the boom 2 is controlled such that the arm tip B moves linearly along the excavation surface G while keeping its height constant.

(III) Bucket control block C _{3 In} this block C ₃ , the basic control amount u ₂₁ of the arm control block C _{1 and} the basic control amount u ₂₁ of the boom control block C _2
14 Togato been written, by a bucket cylinder feedforward calculation means 30 based on the two control quantity u _21, u _14, bucket ground angle theta ₃ the directions match the target value theta ₃₀ bucket cylinder feedforward control amount u ₃₁ is calculated. On the other hand, the detected value of the bucket ground angle theta ₃ by a bucket angle detector 10, a target value of the bucket ground angle. θ ₃₀
From the deviation Δθ ₃ , the feedback control amount u ₃₂ is obtained by the proportional integration means 31. Further, the feedback control amount u ₃₂ is input to the learning unit 32, learning control amount by the same processing as the learning means 26 of the boom control block C ₂
u ₃₃ is output. Then, the feedforward, feedback, and learning control amounts u ₃₁ , u ₃₂ , and u ₃₃ are added to obtain a basic control amount u ₃₄ , which is corrected by the bucket link correcting unit 33 (primary correction control amount u _35). ), and obtains the bucket cylinder control output u ₃ by adding the correction by the nonlinear compensation unit 34. Thus a bucket ground angle theta ₃ is kept constant (target value).

The functions of (I) the arm control block C ₁ , (II) the boom control block C ₂ , and (III) the bucket control block C ₃ are exhibited in combination, so that the control deviation can be efficiently improved, and Excavation control can be performed.

Next, a flat digging and shaping control device for a hydraulic excavator is disclosed in Japanese Patent Application Laid-Open No. 61-270421. This proposal (not shown) includes an operation procedure using a boom rotation speed control unit, a bucket rotation speed control unit, a bucket position control unit, a bucket angle control unit, a boom operation lever, and a bucket operation lever. The boom operation lever is operated to enable manual intervention in automatic excavation.

Problems to be Solved by the Invention A boom, an arm, and a bucket are sequentially rotatably connected to a front portion of a turning pair of a hydraulic shovel. A connecting pin is pivotally connected to the connecting portion between the boom, the arm and the bucket. A slight gap is provided between the coupling pin and the bearing in order to necessitate the attachment and detachment of the coupling pin and to smoothly rotate the coupling pin. Therefore, there is a so-called mechanical backlash in each of the connecting portions.

However, in the hydraulic excavator provided with the conventional excavation control method, it was not possible to correct the deviation of the excavation target track surface caused by the mechanical play during the excavation work.
In order to correct the digging surface angle, the operator has temporarily stopped the control of the digging control method and reset the digging surface angle. Also, in that case, there is no means for determining an accurate value of the angle to be reset, so an excavation accuracy error occurs,
Work efficiency was reduced.

An object of the present invention is to solve the above-mentioned problem and to provide an excavation control method capable of correcting a deviation of an excavation target raceway surface caused by mechanical play of a hydraulic shovel.

Means for Solving the Problems Means of the present invention taken to solve the above problems are as follows. In a prior art excavation control method for an excavation surface,
Operating the operation lever not used for the control by manual intervention to correct and calculate the height of the target linear trajectory with respect to the excavation surface for a predetermined lever operation; b. Further, the angle of the target linear trajectory is corrected for a predetermined lever operation.

Action b. First, here, it is set that the height correction of the target linear trajectory is performed by a boom operation, the angle correction is performed by a bucket operation, and the control start is performed by an arm operation.

When the boom operation lever is operated by manual intervention, the boom operation signal is input to the target height calculation means of the controller. The target height calculating means calculates the target height based on the boom operation signal, and derives a boom cylinder control output in the boom control block based on the calculated target height. Thereby, the height of the target linear trajectory on which the arm tip moves with respect to the excavation surface can be changed for each control cycle of the repetitive excavation operation.

B. When the bucket operation lever is operated by manual intervention,
The bucket operation signal is input to target angle calculation means of the controller. The target angle calculation means calculates the target angle based on the bucket operation signal, derives a boom cylinder control output in the boom control block based on the calculation result of the target angle, and derives a bucket cylinder control output in the bucket control block. . Thereby, the angle of the target straight track with respect to the construction machine can be changed every predetermined cycle.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 is a control block diagram of a controller C ₀ in the embodiment of the present invention. In the figure, the same reference numerals are given to components using the same components as the conventional technology.
41 is a boom operation lever, 42 is a bucket operation lever, C '
₂ boom control block C _'3 is a bucket control block 35 is the target angle calculating means, bucket ground angle calculating means 36, 37 is the target height calculation means. Figure 2 is a flow chart showing the functions of the controller C _'0 in the embodiment of the present invention. FIG. 3 is a side view showing a hydraulic excavator to which the excavation control method according to the present invention is applied. In the figure, 43 is a revolving body of the excavator body, 44 is a boom 45, an arm, 46 is a bucket, 47 is an idler link,
O 'is a connection point between the revolving body 43 and the base end of the boom 44, A' is a connection point between the end of the boom 44 and the base end of the arm 45, and B 'is a connection point between the tip of the arm 45 and the base end of the bucket 46 (that is, B 'Is the same point as the arm tip), D is the arm 45 and idler link
Connection points 48, 49, and 50 with 47 are rotation angle detectors provided at connection points O ', A', and D, respectively. FIG. 4 shows the state of the boom operation when the boom operation lever 41 is manually interposed,
It is a chart which shows the relationship with the height h of the arm front-end | tip B '.

Next, an excavation control method according to the present invention will be described with reference to FIGS.
Referring to FIG. Target height calculation means of the controller C _'0 a boom operation signal i ₁ by the boom operation lever 41 37
And the bucket operation signal by the bucket operation lever 42
i ₂ is set so that it can be input to the target angle calculation means 35, and when the boom operation lever 41 is operated by manual intervention, the height h of the target straight-line trajectory B (see FIG. 3) with respect to the excavation plane G 'is repeated. The angle deg of the target straight track B with respect to the hydraulic shovel body is changed at predetermined intervals when the bucket operation lever 42 is operated by manual intervention.

Next, the function of the excavation control method according to the present invention will be described. First, here, it is set that the height correction of the target linear trajectory is performed by a boom operation, the angle correction is performed by a bucket operation, and the control start is performed by an arm operation. When the boom operation lever 41 is operated by manual intervention, the boom operation signal i ₁ is input to the target height calculation means 37 of the controller C _'0.
Performs calculation of target height calculation unit 37 in the target height by the boom operation signal i ₁ (arm end the same as the height desired value y _b0), the boom control based on the target height is calculated result (y _{b0) 'in second} boom cylinder control output _u' block C to derive _one. Thus, the height (y _b0 ) of the target linear trajectory B at which the arm tip B 'moves with respect to the excavation plane G' can be changed for each control cycle of the repetitive excavation operation. Further, when the bucket operation lever 42 is operated by manual intervention, the bucket operation signal i ₂ is input to the target angle calculating unit 35 of the controller C _'0. The target angle calculation means 35 calculates the target angle β based on the bucket operation signal i ₂ , and the boom control block C ′ ₂ derives a boom cylinder control output u ′ ₁ based on the calculation result of the target angle β, deriving the _{3 'bucket} cylinder control output u _3' bucket control block C. Thereby, the angle (β) of the target straight track B with respect to the hydraulic shovel can be changed at predetermined intervals.

Therefore, when the operator manually intervenes in the boom raising operation, the target height h of the target linear trajectory B is increased by the dimension Δα in each control cycle as shown in FIG. The height h can be reduced by the dimension Δα. When the operator performs a bucket excavation operation, the angle β (deg) of the straight track surface is added by an angle Δβ for each control cycle, and when the bucket ejection operation is performed, the angle deg of the straight track surface is changed for each control cycle. , The control operation is performed on the newly updated target height h and angle deg, and the trajectory of the cutting edge of the bucket can be changed.

Effect of the Invention With a hydraulic excavator provided with the conventional excavation control method, it is not possible to correct the deviation of the excavation target raceway surface caused by mechanical backlash caused by the connection between the boom, the arm and the bucket during the excavation work. Was.

However, in the excavation control method according to the present invention, by performing a manual intervention operation of the boom operation lever, the height of the target linear trajectory at which the arm tip moves with respect to the excavation surface is changed every control cycle of the excavation operation. be able to. Also, by performing the manual intervention operation of the bucket operation lever,
The angle of the target linear trajectory with respect to the hydraulic excavator can be changed at predetermined intervals.

Therefore, in the construction machine provided with the excavation control method according to the present invention, since the deviation of the target excavation track surface can be corrected, the excavation control error caused by the mechanical play of the construction machine can be reduced.

[Brief description of the drawings]

FIG. 1 is a control block diagram of a controller in an embodiment of the present invention, FIG. 2 is a flowchart showing functions of the controller in the embodiment of the present invention, and FIG. 3 is a hydraulic excavator to which the excavation control method according to the present invention is applied. FIG. 4 is a drawing showing the relationship between the state of the boom operation and the height of the arm tip when the boom operation lever is manually interposed, and FIG. 5 is a diagram of a hydraulic shovel operated by a conventional excavation control method. FIG. 6 is an external view, FIG. 6 is a control block diagram showing a conventional excavation control method—basic embodiment, and FIG. 7 is a functional block diagram of a controller in the embodiment of the conventional technology. 2,44 boom 3,45 arm 4,46 bucket 5 boom cylinder 6 arm cylinder 7 bucket cylinder 35 target angle calculating means 36 bucket-to-ground angle calculating means 37 … Target height calculation means 41… Boom operation lever 42… Arm operation lever C ₀ , C ′ ₀ … Controller C ₁ … Arm control block C ₂ , C ′ ₂ … Boom control block C ₃ , C ′ _3. Bucket control block

Claims (1)

(57) [Claims] A boom, an arm, and a bucket; a position detecting means for detecting an angle position of each of the boom, the arm, and the bucket; An operating means for operating each actuator and a setting means for setting a target value of the excavation angle are provided. By operating only one of the set operation levers, the bucket moves with a constant relation to the excavation surface. In the excavation control method, the operation lever not used for the operation in the above control is
By operating with manual intervention, the height of the target linear trajectory with respect to the excavation surface is corrected and calculated for a predetermined lever operation, and the angle of the target linear trajectory is corrected and calculated for a predetermined lever operation. An excavation control method for a construction machine, comprising: