JPS61153702A - Soft structure work machine - Google Patents

Abstract

PURPOSE:To position an arm with a high accuracy by calculating an angular acceleration of the arm in accordance with an output of an angle detecting means of the arm, etc. and a distortion sensor, also calculating a deflection quantity of the arm, and correcting a position command signal. CONSTITUTION:A soft structure work machine installs a turning body 2 to its body 1, and it is provided with an arm body 2a to which plural arms 3, 5 have been connected so as to a turnable. These arms 3, 5 are driven by hydraulic cylinders 4, 6. Also, angle gauges 10, 11 and distortion sensors 7, 8 are provided on said arms 3, 5, and the output is provided to an acceleration compensation control device 13 and a distortion quantity arithmetic unit 17 through the respective detecting circuits 11, 12. As for an operating speed which has been commanded from an input device 15, its difference to an actual val ue is calculated by a relational operation control device 14, and said cylinders 4, 6 are controlled. Also, a corrected value of an angle is derived by a deflection quantity compensation control device 18 and outputted to a correcting device 19, and a target angle is corrected through a coordinate converter 20 from a position command signal generating device 21, and outputted to a servo amplifier 16.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The invention is a multi-purpose Yura cargo handling machine, a robot, etc., and a storm body 1c stone formed by connecting a plurality of arms rotatably to each other.
Posthumous works@i related.

[Evening of invention]

In assembly work, construction work, etc., there is a growing need for work machines having attributes with multiple degrees of freedom from the viewpoint of single-handed labor or diversification of work contents.

Also, in terms of manufacturing costs, Sakumokushin is a 4! ! The introduction of i-devices has become a nuisance for manufacturers.

In such a situation, assembly robots and physical robots have been proposed in recent years, but these robots have a relatively short arm (storm body) length of 2 to 3 meters, so even if they have a rigid structure, it is difficult to manufacture them. There is little impact on the cost price.

By the way, in the case of working machines such as construction machines, for example, two long arms are connected to each other in order to handle heavy objects.
I feel safe with arms that have multiple joints from 0 to 30 meters,
Creating a rigid structure like the assembly robot and painting robot mentioned above in such a work machine requires not only increasing the size of each arm, but also increasing the size of the actuator that moves these arms. Manufacturing costs are high, and in the end, there is a shortage of men. Therefore, a work machine with a flexible structure in which the arm shape is made thinner can be considered, but in such a work machine, the rigidity is low, so the natural frequency is low, and the actuator that drives the arm has a low start-up. When lIh,
The low loss frequency pulsations that occur when the vehicle is stopped do not decay over time, and therefore the arm is likely to vibrate, deteriorating the operability of the arm.

In addition, when controlling the position of the tip of the arm in such a working machine, the arm becomes deflected due to its own weight or a load such as a suspended load, making it difficult to control the position with high precision.

Generally, it is effective to add a damping effect to the vibration in order to suppress vibration #7 as described above, and as a countermeasure, for example, providing a mechanical damper may be considered.
If this is done, there is a problem that the arm shape becomes larger. In addition, as a measure to eliminate the above-mentioned deflection, it is better to use a structure as rigid as possible, but the disadvantages of using this rigid structure are as described above.

[Purpose of the invention]

The present invention has been made in view of the actual situation in the prior art, and its purpose is to suppress vibrations occurring in the arm and to position the arm with high precision regardless of the deflection occurring in the arm. The objective is to provide a flexible construction work machine.

[A view of the invention]

To achieve this object, the present invention comprises a pedestal and a plurality of arms rotatably connected to the pedestal and rotatable with respect to each other, one of these arms being provided with an external load. an arm body consisting of a specific arm; an actuator for driving the arm; an input device for commanding the operating speed of the actuator; an angle detection means for detecting a rotation angle of the arm body and a relative angle between the arms; a strain sensor attached to the sensor, an acceleration compensation control device that calculates the angular acceleration of the arm according to the signal value output from the angle detection means and the strain sensor, and a signal value output from the input device and the acceleration compensation control device. A comparison calculation control device that calculates the difference between output signal values, and a specific arm position tx.
The deflection m of the arm is calculated according to the first signal output from the position command signal generator, the angle detecting means, and the strain sensor, and the arm is output from the position command signal generator according to the amount of deflection. The actuator is configured to include a correction means for correcting a signal value, and to control the actuator according to a signal output from the comparison arithmetic control device and a signal output from the correction means.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Below, the structure of the present invention will be explained based on the drawings.

FIG. 1 is an explanatory diagram showing the basic configuration of an example of uninvention.

In this figure, 1 is a main body, 2 is a frame attached to this main body 1, for example, a rotating body that can rotate with respect to the main body 1, 2a
is an arm body rotatably connected to the rotating body 2, and this arm body 2a includes a plurality of arms, for example, a first arm 3 connected to the rotating body 2 via a bottle, and this first arm 3. It consists of 8+42 arms 5, which are specific arms rotatably connected to via a bottle and to which external loads TL such as shipping are applied. Note that the first arm 3 and the second arm 5
It is designed to be damped as much as possible and is formed into a slender shape that is prone to vibration and non-negligible deflection. Also 4 is the same body 2
The actuator mounted on the first arm 3 'kl1gi# is a hydraulic cylinder, 6 is the first arm 3
The second arm 5 fT: An actuator for rotating the second arm 5 fT, which is, for example, an oil field cylinder.

Reference numeral 10 denotes an angle detecting means, for example, an angle meter, which measures the rotational angle of the arm 2a, that is, the rotation angle of the rotating body 2, the arm 3 of the welding unit 1, and the 1st (1) 1-m with respect to the horizontal line passing through the pin for making lees. The rotation angle σ1 is revealed. 9 also has the angle dtk of the angle dtk between the first arm 3 and the arm 5 of the second arm.

7.8 is a strain sensor of each Vcm layer of arm 3.5, which detects the strain of arm 3.5 caused by acceleration. 7't, 11 outputs Hisumi Dotm from the output signal from the strain sensor 7.8, detects tg1m and outputs the temperature as @, 12 determines the angle from the output signal from the corner 11g↑1O19, A detection circuit outputs it as a signal.

9, 15 is an input device that detects the operation of the hydraulic cylinder 4.6, that is, the angular velocity i of the arm 3.5;
This is an input device that outputs the numbers the and θ2r, and is placed in an operating silkworm (not shown), for example, and is added to the Φ mechanical lever. 1
3 has a bypass filter, and in response to the signals output from the U-way 11 and 12, the arm 3.5 has an unpacking inertia hook that raises the angle ytt'' which is generated at the end of the arm 3.5. The reference numeral 14 is a ratio control filter that calculates the difference between the signal value output from the input iron 15 and the signal 11N output from the acceleration device 13.

The contents of the processing carried out in the above-mentioned accelerated concealment compensation control scissors tit13 are as follows. That is, the signal detected by the detection circuit 11 in response to the signal output from the strain sensor 7.8 has an output characteristic M shown in FIG. 2(a). Of the output characteristics shown, steady strain due to hanging loads, etc.
) is removed in a bypass filter, and only the distortion due to acceleration 1lIl:(AC component 31)ε is extracted as shown in FIG. 2(b). The difference between this strained child ε and the acceleration α of the arm is 1 μ = K,・α
Since the relationship (1) holds, the accelerations generated at the tip of the arm 3.5 are α2.5 and α2.5, respectively, as shown in FIG. α2, these α1. α can be easily determined from the above equation (1). Also, the circumferential fulcrum 0IsO of arm 3.5
Angular velocity around 2 θ1. Between θ and the above acceleration αhα, if the arm lengths are 3.50 ls and lt, respectively, ゛α1=601 (2) αt”
There is a relationship of Aft's+αtt (3). Note that α1 in equation (3). is the first arm 3
This false is the acceleration component caused by the production.

From Figure 3, αn=((it l*11cosfJ)/lsl*
) αx (4). Be friends, α8.
α8. By finding θ, 0. ,0. Angular acceleration around 01. θ.

is obtained. The angular acceleration σ, obtained in this way.

The value θ is output to the ratio control device 14.

Further, the processing contents performed in the comparison calculation control iron fit14 are as follows. That is, in the first arm system, the signal θ1r from the input device [15] and the (g number θ) from the acceleration compensation control table tjlt13.

Find the difference ε1 from the value multiplied by the coefficient Katfc, and calculate this difference 6
Multiply 1 by wLKma1 to find fc1kuv, and also the second
For the arm thread, the signal θ2r from the input device 15 and the signal θ from the acceleration compensation system 13 have a coefficient α2'.
Find the difference ε8 from the km-digit value, and multiply this difference ε by a coefficient.
Find the value Vt 't' by multiplying these Vt -Vt
Output k.

Returning to FIG. 1, 21 is the position of the second arm 5, for example, the digit 1 of point O8. A position command signal generator that outputs signals X, yII- corresponding to the X-Y coordinates,
It is arranged in an interlocking manner (not shown). 20 is a position command signal generator [signals xa y output from 21 are connected to angle fingers +
This is a coordinate conversion device that converts into numbers 01r and θ2r, respectively. 17 has a low-pass filter and a comparison function, and calculates the amount of deflection generated in the arm 3.5 according to the signals output from the detection circuits 11 and 12, and calculates the X-Y sitting image based on this amount of deflection. A bending lid calculation device 18 calculates correction values Δx, Jy for the deflection amount calculation device 17, which calculates correction values Δθ8, . a deflection compensation control device that calculates ΔU;
19 is the angle θ1. output from the coordinate conversion device 20. .

At 02r, the positive value Δ01. Perform the operation of adding Δ02 411
! In the normal device, these deflection calculation device li: 17, stiffness compensation control device 18, and correction device 19 are correction means h! for correcting the signal value output from the position command signal generation device 21. has been completed.

The processing contents performed in the above-mentioned deflection foot effecting device 17 are as follows. That is, the strain sensor 7
．． Figure 2 Ca detected according to the signal output from 8.
), in order to extract the steady distortion (DC component 30) εof due to hanging loads, etc., a low-pass filter is used to remove the distortion due to addition and concealment (intercurrent Component 31) t' swims away. In general, this amount of strain εD and arm deflection il
Since the relationship v = KO・εD (5) holds true, the amount of deflection v1%V of arm 3.5
, can be easily obtained from the above equation (5). As shown in Fig. 4, if the angle corresponding to the target position bow of the second arm 5 is 〇t, θ', then θ', #θ1, θ', #θ!
It is. Therefore, the X component and y component of the amount of deflection vl * vt are respectively VIX, Vly, Y2x,
If V2y, Yl x= v, sinθ'1 #VI Sinθ□
vl, = v, cos θS #vlcos 11°v2x = −v, cos (θ; + θ′l−π
/2)=-v! sin (θ1+θriv2.= -v, sin (θ1.10 -π/2)
= v, cos(θ1+02). From this, the correction value Δx in the X direction and the correction value Δy in the Y direction are Δx=vIX+vt! = v, sin O, -v, 5in (θ1+θt)
(6) Δy=v, a+v2゜=vlcos al+v, cos (θ1+θ,
) (n is obtained. The correction values ΔX and Δy of the X-yW mark calculated in this way are output to the deflection amount compensation control device !t18.

Further, the processing contents performed in the deflection assistant control device 18 are as follows. Coordinate conversion device WL20
According to the signals θ1r and θ2r from the second arm 50
The point 0n(X, Y) is x==f1(θ1r-02,) (
8) Y=ft(θ1t+θ2r)
(9) becomes. In general, Y= f (X,, X,
, X, , ...), the errors of X, , ΔX, then the error ΔY of Y is ΔY= CtN7aX, )−
AX, +<af/ax, )-AX.

+(af laX, ) -AX, +--0-0-. Applying this relationship to equations (8) and (9), “X=(a f,/13θiF)*Jθ*+(aft
/aθzr)sΔθyΔy=caft/δθlr)・Δ
θ1 + < art/θθ2r)・Δθ2. By substituting ΔX and Δy from equations (6) and (7) above into equations (lO) and (11), Δθ1 and Δθ are obtained. Δθ1 and Δθ obtained in this way are output to the correction device 19.

Also, returning to Figure 1, 16 is a servo amplifier connected to the above-mentioned comparison calculation control Kl device 14 and correction device 19, and this servo amplifier 16 operates the servo valve 22 that operates the hydraulic cylinder 4 and the hydraulic cylinder 6. Outputs a signal to drive the servo valve ZaW.

In the embodiment configured in this way, the target position t<x, y> of the point 0''l at the tip of the second arm 5 is commanded by the position command signal generator 21 shown in FIG. The target angular velocity F!L of the arm 3.5 is determined by the input device 15.
;r□1. When a2r is commanded, an arrow motion is performed.

That is, the target position t(x
. ,
The servo valve 22.23 is driven, the hydraulic cylinder 4.6 is actuated, and the first arm 3 and the second arm 5 are rotated. Then, the target angle 0 converted by the coordinate conversion device 20
1r+θ2r and the angle θ1. detected via the angle meter 10.9 and the detection circuit 12. θ, deflection amount calculation device 1
At 7, it is hidden, θ, #θ1. .

θ, #θ2r, the strain it (DC component 30
), the flexible lid of arm 3.5 v□.

(5) above to find the correction values ΔX, Δy of Y, X-Y coordinates
The calculations of equations .about.(7) are performed, and these correction values ΔX.

Δy is output to the deflection sleeve compensation control device 18.

The Tomowami t compensation 11tli cape device 18 uses this correction value ΔX
.

Δy and the target angle θl output from the coordinate conversion device 20
The above equations (10) and (11) are calculated from r and θ2r to obtain the angle correction value Δθ1. Δθ2 is calculated and outputted to the correction device 19. Each of the correction devices 19
'1'+Δθ8. θ2r+Δθ is calculated and these values are output to the servo amplifier 16. The servo amplifier 16 thus adjusts the angle (θ1r+Δθ3.θ2
r+Δθ,), the first arm 3 and second arm 5t move further m.

Taking into consideration the deflection that occurs in the first arm 3 and second arm 5 in this way, the arm 3.5, that is, the tip of the arm 5 at the point 0. The position can be tilted to a desired position and bow to a high degree.

On the other hand, as described above, the arm 3.
When the target angular velocities U1r and tJ2r of 5 are commanded, the comparison control device 14 sets the strain sensors 7.8. Based on the strain amount (AC component 31) ε detected via the habituation circuit 11, the above (1) to (4)
)2, the acceleration compensation control device 13 calculates the point O1, (J, the angular acceleration around θ8.θ!
, the coefficient Ka 1 a Ka
2k f5t digit 11! The difference 'Is;'t between L and the angle [';l""" is calculated in the ratio calculation control unit ft14, and a value V1.V corresponding to the difference 61.ε2 is output to the servo amplifier 16. .In other words, servo increase @
Vessel 16. The first part includes the servo valve 22 and the hydraulic cylinder 4.
arm system, and servo amplifier 16, servo valve 23,
The arm thread of wc2, which includes the hydraulic cylinder 6, is controlled at a value V, , V, corresponding to the angular velocity of the arm 3.50, which provides a dampening effect on the vibration system, and the value V is the first
Removal of the influence of acceleration caused by the movement of arm 3 f
Since it is based on the acceleration α shown in FIG. 3, vibrations occurring in the first arm system and the second arm string can be suppressed without causing loss of control.

In the embodiment configured in this manner, the acceleration α1. of the arm 3.5 is measured via the strain sensor 7.8. α
□, and the deflection tvt *'it of arm 3.5 is determined, so a special speedometer and a load detector for detecting external carts such as shipments attached to arm 3 are required. The structure is simple.

In the above embodiment, the arm body 2a is composed of two arms, the first arm 3 and the second arm 5, but the present invention is not limited to this, and the arm body 2a can be composed of three or more arms. Yo [You can also configure it.

Moreover, although the hydraulic cylinder 4.6 is mentioned above as the actuator that drives the arm 3.5, this actuator is not limited to a hydraulic cylinder, and can also be configured with a hydraulic motor. It can also be configured to be driven using pneumatic pressure or electricity instead of hydraulic pressure.

Nine, the above is an angle detection EP that extracts angles 01 and 02.
Although the angle meters 10 and 9 are mentioned as stages, the present invention is not limited to this, and instead of the angle gauge 10.9, the angle detection means may be constructed with a displacement meter that detects the stroke of the hydraulic cylinder at 4.60 strokes. .

[% light effect]

Since the unstructured working mechanism of the present invention is constructed as described above, it is possible to suppress the following movement that occurs in the arm, and to
Regardless of the deflection that occurs in the arm, the arm can be moved to vIL with high accuracy, and therefore construction &! This has an effect that can be applied to work machines such as Kaede, etc., which have a large and bulky arm.

Furthermore, since it is customary to measure the acceleration and deflection tk of the arm through a strain gauge, the structure is simple, and the cost of scissoring is reduced, which is advantageous.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the basic configuration of one embodiment of the unstructured leftover work of the present invention, and FIG. 2(a) is an explanatory diagram showing the output characteristics of the strain gauge provided in the embodiment shown in FIG. 1. , Figure 2 (
b) is the acceleration packing convention provided in the embodiment shown in FIG.
FIG. 2(C) is an explanatory diagram showing the strain characteristics obtained by the processing in the flexural spectral control device provided in the embodiment shown in FIG. 1; FIG. 3 is an explanatory diagram schematically depicting the arm body and state quantities in order to explain the calculations performed in the acceleration inertia control device provided in the embodiment shown in FIG.
The figure is an explanatory diagram schematically depicting a wind body and a state quantity in order to explain the '@ calculation performed in the deflection amount calculating device provided in the embodiment shown in FIG. 1. 2... Rotating body (frame), 2a... Storm body, 3... First arm, 4.6... Hydraulic cylinder (actuator), 5... Second arm, 7.8... Distortion sensor, 9.10.
...Angle meter (angle detection means), 11.12...
...Detection circuit, 13...7 JII's degree control system, 14...Hinu calculation control system, 15...
... Input device, 16 ... Servo amplifier, 1
7. Song/deflection amount calculation device, 18... Deflection amount compensation control device, 19... Correction 4 & setting, 20...
. . . Coordinate exchange device, 21 . . . Position indication signal generator, 22. 23 . . . Servo valve.弗 2 fig. 3

Claims (1)

[Claims] 1. An integral body consisting of a pedestal and a plurality of arms rotatably connected to the pedestal and mutually rotatable, one of which is a specific arm to which an external load is applied, and the arm an actuator for driving the actuator, an input device for commanding the operating speed of the actuator, an angle detection means for detecting a rotation angle of the arm and a relative angle between the arms, and a strain sensor attached to the arm; an acceleration compensation control device that calculates the angular acceleration of the arm according to signal values output from the angle detection means and the strain sensor; and a signal value output from the input device and a signal output from the acceleration compensation control device. A comparison compensation control device that calculates the difference in values, a position command signal generator that commands the position of the specific arm, and a deflection amount of the arm according to the signal values output from the angle detection means and the strain sensor. and a correction means for correcting the signal value output from the position command signal generation device according to the amount of deflection, the signal output from the comparison calculation control device and the signal output from the correction means being depending on,
A flexible structure work machine characterized by controlling the above actuator.