JPS6055413A - Controller for exercising simultaneous playback control over arm and carriage of running type robot - Google Patents

Abstract

PURPOSE:To perform playback control over a robot arm and a carriage by fetching the position of the carriage at previously taught points and performing interpolation, and using those carriage positions for arm interpolating arithmetic. CONSTITUTION:The running type robot 10 has the carriage 12 which moves horizontally and the arm which moves vertically, and a controller 20 while interpolating the position and attitude of the arm 13 drives a driving part 27. This controller 20 is composed of a central processing part 21, etc. The teaching data storage part 23 of the controller 20 stores position data at teaching points by a coordinate system based upon the reference point of the carriage 12 as an origin, and also by a coordinate system based upon the base part of the arm 13 as an origin similarly. The reverse coordinate conversion of the current value and future value of a future value storage part 24 is performed and their difference is calculated to obtain position signals for the carriage 12 and arm 13, which are brought under playback control at the same time.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a control device for a traveling robot, which does not perform playback control on the arm and cart of a busy traveling robot separately, but simultaneously performs playback control on them. [Prior art] Conventionally, in the playback operation of this type of traveling robot, the control of the arm and the control of the trolley are independent, and the playback control of the arm and the trolley is performed simultaneously. Nothing was being done. In other words, conventional mobile robots first position the cart, move/stop the cart, and then perform arm interpolation for, for example, welding work at a complex welding location inside a workpiece or in a narrow space. Welding is performed within the movable range, and then the cart is positioned again, moved/stopped to a different location, and the arm is interpolated again to perform welding at a different welding location. In short, conventional mobile robots only perform discontinuous welding.

However, 1. For example, when trying to weld a workpiece with a long welding length outside the workpiece, conventional traveling robots have to perform various positioning of the cart and interpolation of the arm, which is not only extremely troublesome but also takes time and effort. It is a matter of concern. in this way.

Conventional mobile robots have disadvantages in that they cannot perform playback operations while running, and the movable range of the robot in which continuous work can be performed is limited to only the movable range of the arm.

[Summary of the invention]

Therefore, the present invention has been made in order to eliminate the drawbacks of the conventional traveling type robot as described above. It is an object of the present invention to provide a control device that can perform playback control of an arm and a cart of a traveling robot at the same time by incorporating them into arm interpolation calculations.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

FIG. 1 is a block diagram showing a control device of the present invention and a perspective view showing a traveling robot whose arm and truck are simultaneously playback-controlled by the control device. In the figure, io is a running robot, with a running platform /l, a trolley l that moves linearly in the horizontal direction (X direction) on this running platform ll, and a trolley 7.2 that moves in a vertical direction (Y direction) on this running platform ll. It consists of an arm 13 that moves in a straight line. -〇 is a control device according to the present invention for a traveling robot lθ, which includes a central processing unit 1, 2 control program storage units, a teach data storage unit, 23. Interpolation coefficient, current value/future value storage unit 2'l
, an input/output control section S, a position/orientation control section Colo, a driving section core, a central processing section 21, and the above-mentioned storage section 2--:
4; Consists of I+ common passcode g that sends and receives signals to and from the control section 26;

FIG. 2 is a diagram showing the coordinate system of the traveling robot 10, that is, the coordinate system with the base of the arm 130 as the origin 0', and the coordinate system with the reference point of the truck l- as the origin O. Arm 1
In the orthogonal coordinate system, the coordinate system with the base of 3 as origin 0' is the position k (x',
y' I J' ), welding torch/X of 3a
′ axis, y′ axis, and J′ axis (A.

B, C). Also, in the joint coordinate system, each joint Jt lJJ *J3+JF that constitutes arm/3
IJz, Jg Angle θ, θ, θ3. θda, 0! , θ6 as shown in the figure (θ/, eJ', θ
3,0も, θ! , Ob ). Busy,
The orthogonal system coordinates of arm 13 are expressed as vector lower ma(”+
7', 7+ A t B + C), and the joint system coordinates are vector ■A (θl, θko, θ3゜θke, θ3.θ6
) and 1, the pressure between PA and ■A has the following relationship.

PA 2 MA ・■A Formula (1) ■A = MA - PA formula ((2) Here, MA is the coordinate transformation matrix of arm 13.

1 MA is the inverse transformation matrix of arm 13.

Next, in the coordinate system with the reference point of one bogie 1.2 as the origin 0, the position of one bogie 12 is expressed as (X, Y) in the orthogonal coordinate system, and the angle of each joint J 7 + J t that makes up the bogie 1. θ7,
If 0S is expressed as (θ7.θK) in the joint coordinate system, the orthogonal system coordinates of the cart 12 are vector P T (X,
Y), and the joint system coordinates are vector ■T(O9,
θl), and the following relationship holds between them.

PT = MT ・ ■T Formula (3) ■T = MT-'・ P = Formula (g) Here, 5MT is the coordinate transformation matrix of trolley 12, MT
/ is the inverse transformation matrix of the cart saw.

When the tip position of the welding torch i3a is expressed in an orthogonal coordinate system with the reference point of the cart saw as the origin O, the coordinate vector of the welding torch i3a ``(x+y e )) is X '': )
('+

c, x, y).

Figure 3 shows the central processing unit-7 and the position/orientation control unit:
16, and using this functional block diagram, the operation of the present invention will be described first with respect to tee fy/, and then with respect to playback. At the time of teaching, in order to teach the traveling robot 10 the path to weld the work, the position of the tip of the welding torch/Ja and the position of the one-cart saw at each of the plurality of discontinuous points forming the welding distance Pi5 are determined. Arm movement commands θl to θ6, cart movement commands 07 to θ6 expressed in joint coordinate system
At θt', the input/output control section λ is input from the teaching box 31.
5 and the common path control unit one after another to the position/orientation control unit roller, and the traveling robot i via the drive unit core.
oy move it. At the same time K.

The arm movement command 1 carriage movement command is also given to the mechanical forward conversion means F/, and in this mechanical forward conversion means tIl, the formula (/
From l, welding torch /, ? is first determined by an orthogonal coordinate system with the base of the arm 13 as the origin O', and then by an orthogonal coordinate system with the reference point of the trolley saw as the origin 0. Tip position of a (XIYI
J) and the welding torch / , ? according to the orthogonal coordinate system with the base of the arm 130 as the origin O'. fi posture (A, B, C
), the position of the dolly saw is determined by the orthogonal coordinate system with the origin 0 as the reference point of the dolly saw, and these welding torches/Ja
, the position data of the welding torch/3tl, and the position data of the trolley 12 are sequentially stored in the teach data storage section 23 as teach data. Also.

A command regarding an interpolation method for continuously connecting each of a plurality of discontinuous points is also input from the teaching box 31 and stored in the teaching data storage section 13.

Next, I will talk about the control section of the 1st position, Hair Hodai. The position/orientation control roller is a digital servo (not shown)
It is made up of. In other words, the central processing unit 1 stores the angular displacements Δθ7 to Δθt of the respective joints Jl to Jr that are to be changed in a minute time of 67 seconds according to the control program stored in the control program storage unit, for example, ROM VC.
is transferred to the position/orientation control unit Koro through the common puff 2g￥. Then, this position/orientation controller roller performs slow acceleration/deceleration processing in response to the above-mentioned angular displacements Δθl to Δθt', and compares it with the position feedback amount from the position detector (not shown) provided in the traveling robot IO. Drive (speed) commands are output to all drive units with zero errors, and position/orientation control is performed using these commands.

During playback, in order to have the traveling robot lo perform welding as taught, the operation command 3.2 is remotely controlled and an operation command is given. Then, the central processing unit 1 transfers the above-mentioned tip position data, posture data, position data, and interpolation command stored in the teach data storage unit λJ to step 10 of FIG. /, the data is sequentially read out to the interpolation means tI in FIG. Since the teach data consists of a plurality of discontinuous points, for example, PH9P N 4 / in FIG. ) It is necessary to determine the welding route. For this purpose, the interpolation means Guco uses, for example, three-dimensional linear interpolation that connects two points, but may also use circular interpolation that connects three points. Therefore, the Nth teach data point P
Welding torch between N and Nth → 1st teach data point PN+t/? In order for a and the trolley 12 to run continuously and linearly, the following three-dimensional linear interpolation is performed. The orthogonal system coordinates of the teach data point PN are transformed into a vector PQ (
XN l 'IN+ JN, AN, BN+ CN,
XN+YN), and the orthogonal system coordinates of the teach data point pH→l are expressed as vector PN+/ (XN4/ , yN4/
+JN+/+AN4/ 1BN4/+CM-) t 1
XN4 t , YN+ t ), the straight line PNP
N4 The slope of t is 1 vector ΔN (△X, △y, Δ), △
To, ΔB, ΔC.

ΔX, ΔY) can be expressed by the following equation (3).

The interpolation means lλ calculates the value of this slope vector ΔN in step 103, and stores it in the interpolation coefficient, current value/future value storage unit λda as a three-dimensional linear interpolation coefficient.

Next, set the coordinates of the teach data point P)1 to the current value pectA
/ PC! URR(xcUnn, ycuRn, 1cun
R, ^CURR,! 3CUIIR.

CcuRR,
Melt using 1). In other words, the orthogonal coordinate system with the base of the arm 130 as the origin θ' is
I de'cunR.

J'CURR) □ → −−m−−→ −−1−−→ X'CURR""
C! URR(X'CURR, V'CURR, J'CURR
R,ACURR,Bc,.

``CURR).Additionally, use 1 equation (J).

−7−−−→ OA CURR=MA” Please use equation (1) again.

(1) T CURR=MT-'.pTCURR, and from these OA CURR and (2) T CURR, a current value vector of 51 is calculated and stored in the interpolation coefficient, current value/future value storage section Koda.

The orthogonal system coordinates after a minute time of 61 seconds are the future value vector PNX
If T, then the slope vector AM determined by the above formula (&), that is, the three-dimensional value line interpolation coefficient and the welding torch /,? Using the running speed F of a, as shown in the following equation (6), where F is the speed when the torch tip moves in a straight line between pH and p7, and PN and PN4/. ) and store the interpolation coefficient in the current value/future value storage section Koda.

Current value vector■. Similarly to U□, the orthogonal system coordinate vector "N XT (x'H
X T +'! I'NXT J'NXT).

+PA NXT (X'axr, yNxr,, i
'sxT, ANxr, Bsxr.

``NXT).Furthermore, using formulas (J and (9L)), respectively 11→ ■ANXT = NA-/'' pANXT can NXT
= NT-' ・PTNXT, these 673 and e
) From rxxr, the future value Bem-□-→ Kutle ■NXT is obtained and stored in the interpolation coefficient and current value/future value storage section Koda.

The difference between the current value vector ■CURR obtained in this way and the future value vector 0NxT is expressed as follows: −→ −−1 −−1−→ Δ■ = ■NXT −■CURR The value is The angular displacement of each joint J/~J is obtained in a minute time of 67 seconds, and this is determined by the attachment/posture determination control unit, 2
6 (step toe). Then, the position/orientation control unit 26 applies a drive signal to the drive unit core so that each joint JtyJt takes the calculated displacement after a minute time ΔT. Minute time △T7 seconds Cobb, the future value from earlier is stored in the storage unit Cog as the current value, and the above sequence is repeated to control the mobile robot to move between the taught points using the specified interpolation method. .

If these III'IJ controls are performed every 67 seconds,
Welding torch/, the tip of 7a is straight line PHPH4 every 61 seconds
7 above! It can travel at speed F. Also, trolley 7.
2 is also k at speed F-8, nt, = J(x old, -G>"+-"("YN4 t
-'YN)j- indicates the distance between the bogie positions at PN, P□, and -DI- was described above. ). (Step 10!r) Furthermore, since the speed F controls the playback of the △T knot arm and the trolley at the same time, welding can be performed continuously while the traveling robot is traveling, and the work range can therefore be reduced. This results in expansion and, in turn, improved work efficiency.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the control system of the present invention and a perspective view showing a traveling robot controlled by this control device, FIG. 2 is a diagram showing the coordinate system of the traveling robot, and FIG. 3 is a diagram showing the central processing unit and 6R is a logic block diagram of the positioning/attitude determination control section, and FIG. 6 is a grayback flowchart. IQ is a running robot, 12 is a trolley, l, 7 is an arm, 1
．． 7a is welding 1/-chi, θ is atl + goso a, 21 is tp central processing unit, 23 is teach data, cog is interpolation coefficient, current/future value storage unit, roller is position/attitude determination control unit,
λ7 is the drive unit 1, 71 is the teaching box, 3.2
is an operation board, J/ is a mechanical forward conversion means, Guko is an interpolation means, and q3 is a mechanical inverse conversion means. In each figure, the same reference numerals indicate the same or corresponding parts. Agent Masu Oiwa Yuji Figure 4 PN/″′ 1/′

Claims (1)

[Claims] (/l A control device for a mobile robot that plays back and has a cart that moves linearly in the horizontal direction and an arm that moves linearly in the vertical direction on the cart, and a drive unit for driving the moving robot. , a position/orientation control unit for controlling the drive unit, and a coordinate system having the reference point of the truck as the origin, determine the position of the taught point on the truck and store the data. Engineering,
First, a coordinate system having the base of the arm as the origin is first converted into a coordinate system having the trolley reference point as the origin, thereby determining the position of the arm at the taught point and the coordinates with the base of the arm as the origin. A teaching data storage section in which the posture of the arm at the taught point is stored by the system, a specified interpolation coefficient between the taught points, current value data of the cart and the arm, and a storage section in which future value data after a minute time determined by the interpolation coefficient is stored; and after coordinate inverse transformation of the current value data and future value data stored in this storage section, the difference between them is calculated. a central processing unit that generates a displacement signal for the trolley and the arm and supplies this displacement signal to the position/orientation control unit, and performs playback control of the arm and the trolley at the same time. Device.