JP3007440B2 - Offline teaching device for robots - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot offline teaching device.

[0002]

2. Description of the Related Art Conventionally, in order to teach the contents of work to a working robot, an operator carries a teaching box and enters the operating range of the robot, and teaches while manually operating a desired robot itself. The method was common. However, this method has a serious economical problem that an operable robot needs to be paused for a long time for teaching, and furthermore, a long working in a dangerous place for a teacher is physically. It is a great mental burden.

Therefore, a system has been developed in which a model of a robot or a work is constructed on a computer independent of a controller of an actual robot, and the model is used for studying and teaching arrangements. Is disclosed in
No. 5,779,579, and Japanese Patent Application Laid-Open No. 59-229419.

Further, position data taught off-line,
A method of correcting a “deviation” from required position data at a site where a robot is actually installed is disclosed in
-206809, JP-A-60-65304 and the like.

[0005]

However, the conventional method as described above has the following problems. (1) The position data of several representative points on the work target object is measured by a robot that has already been installed, but the work itself is a work that conforms to the direct teaching method using a teaching box. It has the same drawbacks as teaching.

(2) A robot controller as disclosed in JP-A-63-206809, or
In an editing apparatus installed at a factory site as disclosed in Japanese Patent Application Laid-Open No. 3-273912, in the case of a system that corrects "shift", correction information of "shift" is transmitted to a CAD system that generates teaching data. Because there is no
Each time new teaching data is transferred from the CAD system to the robot, it is necessary to correct the "shift" in the control device and editing device. Also, the teaching data before and after the "shift" is corrected at the factory site. Are mixed, causing confusion in data management.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object the following.
In the following points. (1) When a robot measures position data of a representative point on an object to be worked by the robot, the robot automatically performs a series of operations to be performed for the measurement work according to a program created in advance, thereby performing the work. Free from sensitive and dangerous alignment (measurement) work.

(2) By updating and storing the position of the CAD model of the target object based on the on-site data obtained by the robot measurement, a new robot program having different teaching data for the same target object as in the past can be created. When it is created, the "shift" correction work is not required.

[0009]

In order to achieve the above object, an off-line teaching apparatus for a robot according to the present invention accumulates data relating to a robot, peripheral devices, and works, displays the data on a graphic display, and CAD system having means for simulating the operation of the robot, peripheral devices and workpieces by using the program created by the present invention, and means for correcting the actual displacement of the position / posture data of the work object on the three-dimensional CAD system A personal computer connected to the simulation means and having means for converting the program into a program in accordance with a grammar of a desired robot language, and a robot controller or the like for controlling the robot. Offline teaching of robots that teach motion In the device, means for easily teaching a series of operations of the contact detector required to measure the position of the detection target object offline, a plurality of grippers, and detecting only the presence or absence of contact with the work target object A fitting provided on the gripper and the contact detector so that the mounting position is always constant even when the contact detector that measures the position and orientation of the work object is installed and the gripper and the contact detector are attached and detached. A mounting seat part attached to the hand of a robot having a positioning pin corresponding to a hole for use, and a means for electrically outputting a contact state between an object to be detected and a contact detector, wherein the contact detector is provided at the hand of the robot And, means for storing and holding the position data of the contact detector at the moment when the contact target is in contact with the detection target object, and calculates the position of the detection target object from the stored and held position data, Means for data transfer to the AD system, characterized in that a means for correcting the position of the CAD model of the work object including the detection target object.

[0010] Further, the present invention is characterized in that a mounting structure is provided in which these action lines are the same when the contact detector is replaced with the gripper.

The intersection of the action lines of the gripper and the contact detector intersects in one turn, and the intersection is on the final rotation axis of the robot.

[0012]

According to the present invention, according to the present invention, the position / posture of a detection target object is detected by a contact detector provided at the hand of a robot, and a series of operation programs are created using a CAD system. In accordance with this program, the required position data of the object to be detected is measured and temporarily stored, the position of the object to be detected is calculated from the position data and transferred to the CAD system, and the position and orientation of the model of the object to be detected are corrected. By doing so, it becomes possible to release the worker from dangerous positioning (measurement) work when measuring the position data of the work target object with the robot.
Also, when a new robot program with different teaching data is created for the same target object,
Correction work is not required.

A mounting seat part is attached to the hand of the robot, and a plurality of grippers and a contact detector are attached to the mounting seat part. A contact pin is provided on the mounting seat part and a hole provided on the detector side is fitted, so that the contact detector is provided. Since the attachment position is always constant even if the is attached or detached, it can be efficiently performed when the combination work of the measurement and the work by the gripper is repeated one after another. After the measurement, if the contact detector is removed and another gripper is attached, the operation can be performed using more grippers, and the attachment positions can be easily reproduced.

[0014] Further, by providing a mounting structure in which these action lines are the same when the contact detector is replaced with the gripper, there is no need to redefine the action lines. Further, since the intersection of the action line of the gripper and the contact detector intersects in one turn, and the intersection is on the final rotation axis of the robot, only by rotating the final axis of the robot, the contact detector previously The gripper can be moved so that the line of action of the gripper coincides with the position where the line of action was present, and switching between the measurement operation and the operation by the gripper is facilitated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment.
First, the configuration of the system of the present invention will be described with reference to FIG.
The device of the present invention comprises six parts: a CAD system 1, a personal computer 2, a robot controller 3, a robot body 4, a contact detector 5, and an interface device 6 for the contact detector.

Next, the software configuration of the present invention is shown in FIG.
It will be described according to. As shown in the drawing, in the present invention, a conventional robot teaching system, that is, a CAD system 13, which performs target work teaching, a personal computer 14, a robot controller 15, or a "shift" correcting means, that is, a robot which stores a detected position. A system including a controller 10, a personal computer 11 for calculating the position of an object to be detected, a CAD system 12 for correcting the position of a work object model, and the like, and a CAD system 7 for teaching measurement operations, a personal computer 8, and a robot controller 9 In addition, a means for generating an operation for the robot to measure a representative point in the flat plate 25 (see FIG. 8) as an object to be worked off-line is added.

Here, means for generating the measurement operation of the representative point off-line will be described. In the CAD system,
At least the model of the robot and the work target object, peripheral devices, and the work are input based on the design data.The Lopot model has the same mechanism operation means as the actual machine, and the robot is operated by the instruction of the robot. Operation definition and operation simulation are possible. In addition, the above-mentioned peripheral device is an assembly jig, a transfer device, and all other devices existing around the robot. Further, in the above description, the work means the grippers 21, 22, 23 of the robot.
(Refer to FIG. B) is an object (product part) gripped by (see FIG. B).

In this embodiment, as described below, a cylinder is measured in order to obtain the position of the representative point of the work object. In order to facilitate the teaching of this measurement operation, an identification name is given to the cylinder model, while only the operation pattern is defined, the identification name of the cylinder to be applied is input later, and the input identification of the cylinder is performed. Create a program that automatically combines names with operation patterns. For example, if this program name is "M
EASURE ", and a measurement operation of a cylinder having an identifier" ENCHU1 "is generated, the MEASUR
What is necessary is just to input E (ENCHU1).

Next, the program will be described in more detail with reference to the drawings. First, a flowchart of the entire program is shown in FIG. In the figure, first, a cylinder identifier is read, a second operation point group is generated and an identifier is assigned, and a third operation simulation command is listed.

FIGS. 4A and 4B show a more detailed flowchart of the third processing. That is, in step 100, a move command is issued to P1-U, and
In step 2, a move command is issued to P1-D. In step 104, a search is performed toward the center of the cylinder. In step 106, the position of the contact detector is stored. In step 108, a move command is issued to P1-D. Sends a move command to P1-U.

FIG. 5 is a mounting diagram of the contact detector. In this embodiment, a contact detector and a gripper (gripping means) are attached to the hand of the robot in order to measure the position and orientation of the work target object. That is, three grippers 21, 22, and 23 for gripping parts and a contact detector 2 using the same mounting method as the grippers 21, 22, and 23 are attached to a mounting seat part 20 for mounting grippers and the like of the robot body.
4 is installed.

As shown in FIGS. 6 (a) and 6 (b), the contact detector 24 is fixed by several fixing bolts 30 similarly to the gripper. Consideration has been given so that the position at the time of the previous installation can be easily reproduced. That is, the mounting seat part 20 is attached to the hand of the robot, and a plurality of grippers 2 are attached thereto.
1, 2, 23 and the contact detector 24 are attached side by side, and the contact is made by fitting a positioning pin 31 provided on the mounting part 20 on the robot side with a hole 32 provided on the contact detector side. Even if the detector 24 is attached or detached, the attachment position is always fixed. Therefore, at the end of the "shift" correction process, the contact detector 24 can be removed and another gripper or the like can be attached instead. Of course, the contact detector 24 may be left attached as long as it does not hinder the work.

The contact detector 24 used in this embodiment is
When the detection probe 24a hits an object, the axis of the detection probe 24a is tilted in all directions around the axis of the main body 24b, and the detection probe 2 is compressed in the axial direction of the main body.
4a can also move.

Further, in this embodiment, as shown in FIG. 7, a mounting structure is provided such that when the contact detector 24 is replaced with the grippers 21, 22, 23, these action lines are the same. Then, the intersections of the action lines of the contact detector 24 and the grippers 21, 22, 23 provided side by side intersect at one point,
And the intersection point is on the final rotation axis of the robot.

FIG. 8 shows an example of an object to be worked by a robot. In this embodiment, there are cylinders 26, 27, and 28, which are representative points of a work target object, on a flat plate 25, and a work point group to which the robot should actually give a work effect, for example, a part gripping point group 29. In the “deviation” correction process, the cylinders 26, 2 serving as detection target objects in the robot's reference coordinate system are used.
7 and 28 (X1, Y1, Z
1), (X2, Y2, Z2), and (X3, Y3, Z3), the spatial position data (X, Y, Z, α,
β, γ) is determined, the position of the CAD model of the flat plate 25 is corrected, and thus the position data of the working point group 29 on the flat plate 25 in the reference coordinate system of the robot is obtained.

In order to apply this method, it is necessary that the positional relationship between the cylinder and the work point group is sufficiently accurately input to the CAD model. If the cylinder is inserted into the hole, the positional accuracy can be ensured.

FIG. 9 shows an operation path of the contact detector 24 for measuring the position of the column 26 (27, 28). That is, first, three points around the cylinder are detected to determine the position of the center axis of the cylinder, and then the upper surface of the cylinder is detected.
The detection operation of each point moves slowly from the approach point around the cylinder far enough away from the cylinder toward the cylinder,
The movement stops as soon as the probe of the contact detector contacts,
The contact signal is input to the robot controller, the robot controller stores the position of the contact detector at that time,
It moves to the approach point and goes to the next detection point. It can be easily inferred that such a measuring method can be applied to not a cylinder but a hole.

Here, three points on the circumference are represented by (x1, y1)
Assuming that (x2, y2) (x3, y3), the following conversion is performed to simplify the equation for calculating the center of the circle. X12 = x1 + x2 Y12 = y1 + y2 X13 = x1 + x3 Y13 = y1 + y3 XB12 = x1-x2 XB12 = y1-y2 XB13 = x1-x3 XB13 = y1 -Y3 The center of the circle is calculated using this equation.
Assuming that the center coordinates of the circle are (CX, CY), X12 × XB12 + Y12 × YB12-2 × CY × YB12 CX = ──────────────────────── ──── XB12 × 2 XB12 × XB13 × (X12−X13) + XB13 × Y12 × YB12−XB12 × Y13 × YB13 CY = −──────────────────── ─────────── (XB12 × YB13−XB13 × YB12) × 2.

FIG. 10 is a flowchart for calculating and obtaining position data of the center axis of the cylinder from position data on the cylinder obtained by the detection operation described with reference to FIG. In the figure, initialization is performed in step 200, and the number of circles en and the file name f1 are determined in step 202.
Is stored. In step 204, the number of circles is subtracted by one and e
In step 206, it is determined whether the denominator is 0 or not. And the center coordinates (CX, CY) of the circle
If the denominator of the equation (2) = 0, the process proceeds to step 208; Here, the center coordinates are calculated, the coordinates are displayed in step 212, and the
And the end condition en = 0. If the number of times is 3 or less in step 208, the process returns to step 206. If the number of times is 3 or more, the process proceeds to step 216. Then, in step 218, a file is output. In the present embodiment, this calculation is performed on the personal computer 11 in FIG. 2, but may be performed using the calculation function of the CAD system.

[0030]

As described above, according to the present invention, the contact detector, which is a single sensor for detecting only the presence or absence of contact with the object to be detected, is attached to the hand of the robot via the mounting seat part. Instead, the CAD system generates a complicated detection operation that complements the function with a small number of contact detectors, and generates an X.Y.Z. Since the multi-variable position and orientation variables β and γ can be obtained, the following effects can be obtained. When measuring the position data of the representative point of the work target object of the robot with the robot, the worker can be released from subtle and dangerous positioning (measurement) work. When a new robot program with different teaching data is created for the same target object, "shift" correction work becomes unnecessary. Measurements corresponding to various positions and shapes of the work object to be measured can be performed.
The work using the gripper can be performed immediately after the measurement, and when the combined work of the measurement and the work by the gripper is repeated one after another, the work can be efficiently performed. When the measurement is completed and the contact detector is no longer needed, the contact detector can be removed and another gripper can be attached, so that more grippers can be used and work can be performed. The mounting position can be easily reproduced even if it is detached. When the contact detector is replaced with a gripper, there is no need to redefine the action line. By simply rotating the robot's final axis, the gripper's action line can be moved to the position where the contact detector's action line used to be before, making it easy to switch between measurement work and work by the gripper. .

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a robot offline teaching device.

FIG. 2 is a block diagram showing a flow of software processing of an off-line teaching method of a robot.

FIG. 3 is a diagram showing a schematic flowchart of a program for automatically generating a measurement operation.

FIGS. 4A and 4B are diagrams showing detailed flowcharts of FIG. 3;

FIG. 5 is a perspective view showing an attached state of a contact detector.

FIG. 6A is an exploded perspective view of a contact detector,
(B) is the A arrow view.

FIG. 7 is a diagram showing the relationship between the final rotation axis of the robot and the action lines of the contact detector and the gripper.

FIG. 8 is a diagram illustrating an example of a work target object of the robot.

FIG. 9 is a diagram illustrating an example of a measurement operation on a detection target object.

FIG. 10 is a diagram showing a flowchart of a calculation program for obtaining position data of a detection target object.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CAD system 2 Personal computer 3 Robot controller 4 Robot 5 Contact detector 6 Contact detector interface device 20 Mounting seat parts 21, 22, 23 Gripper 24 Contact detector 25 Flat plate (work object) 26, 27, 28 Cylinder (detection) Target object) 30 bolt 31 positioning pin 32 positioning hole

Continuation of front page (51) Int.Cl. ⁷ Identification code FI G05B 17/02 G05B 17/02 19/4097 19/403 C 19/42 R (56) References JP-A-1-92808 (JP, A) JP-A-1-131904 (JP, A) JP-A-62-151072 (JP, U) JP-A-62-158269 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05B 19/42 G05B 19/4097

Claims (3)

(57) [Claims] 1. means for accumulating data relating to a robot, peripheral equipment and a work, displaying the data on a graphic display, and further simulating the operation of the robot, peripheral equipment and the work by a program created by an operator; A CAD system having means for correcting the actual amount of displacement between the position and orientation data of the target object on the three-dimensional CAD system, and a program which is connected to the simulation means and converts the program into a program conforming to a desired robot language grammar In order to measure the position of the object to be detected in a robot offline teaching device, which is composed of a personal computer having a conversion means and a robot controller that controls the robot, and teaches the operation of the robot without using the actual robot, A series of necessary operations of the contact detector Off-line teaching means, multiple grippers, and a contact detector that detects only the presence or absence of contact with the work object and measures the position / posture of the work object is attached and attached, and makes contact with the gripper A mounting seat part attached to the hand of a robot equipped with positioning pins corresponding to the fitting holes provided on the gripper and the contact detector so that the mounting position is always constant even when the detector is attached and detached. A means for electrically outputting the contact status between the contact target and the detection object, which is provided at the hand of the robot, and the position data of the contact detector at the moment when the detection object contacts the contact detector. Means for calculating the position of the detection target object from the stored position data and transferring the data to a CAD system; and a CAD module for the work target object including the detection target object. Off-line teaching device of the robot, characterized in that a means for correcting the position of the Le. 2. The offline teaching of a robot according to claim 1, further comprising a mounting structure in which when the contact detector is replaced with a gripper, these action lines are the same. apparatus. 3. The teaching device according to claim 1, wherein the intersection of the action line of the grip detector provided in parallel with the contact detector intersects one turn, and the intersection is on the final rotation axis of the robot. Offline teaching device.