DE102008036501A1 - Method for operating robot arm involves moving carrier component into measuring position above object by robot arm, where precise storage position of object is detected with multiple camera systems - Google Patents

Abstract

The method involves moving a carrier component into a measuring position above an object by a robot arm. A precise storage position of the object is detected with multiple camera systems (5). A required adjustment of the position of the robot arm takes place depending on the detected data. An independent claim is included for a robot arm.

Description

The The invention relates to a method for operating a robot gripper and a related robotic gripper consisting of a carrier assembly attached to a robotic arm is and can be moved by this in several degrees of freedom, wherein the carrier assembly comprises a plurality of suckers, the each equipped with an elastic absorbent body, the on the object to be gripped, in particular a disc for motor vehicles, mounted and subjected to negative pressure is and wherein at least one stop is provided, in the gripping direction displaceable relative to the carrier assembly and by means of a Clamping device can be locked in a defined position.

For Numerous technical applications are automated assembly processes realized using robotics. For the use of such Robots must exactly match the assemblies to be joined be brought into a mutually defined relative position to To avoid mistakes in the assembly process.

A in this case typical application is the installation of glass panes on sheet metal parts of a body on production lines of the automotive industry. The discs have a dimensionally accurate outer contour on, allowing a fit between the recess in the sheet metal part and ensures the disc to be mounted in the recess is. Nevertheless, the handling of the vehicle windows is problematic because these are predominantly several sections with one each have different curvature.

For automated assembly of vehicle windows robotic grippers are used which have suction cups for gripping and stops for positioning the pane. Such a technical solution is out DE 37 16 232 C2 known. Here, a handling device with gripping device and a mechanical centering device is used for mounting vehicle windows. The centering device has at least one sensor which is moved along with the gripping device and which is guided along the contour of a cutout in the body.

Out DE 297 12 202 U1 a system for the installation of vehicle windows in bodies is known in which a non-contact measuring system is arranged in the region of the assembly station, with which the position of the discs is detected on a feeder.

outgoing from this position becomes a robotic gripper via a controller moved so that it fits the disc in a montagegerechte to the body Shifted position. For the contactless measuring system several cameras are used.

Independently of the particular variant for the measurement of body cutout and to be mounted vehicle window problems arise, if worked on a plant different body or disc shapes should be. A conversion of the robotic gripper for the installation of different discs requires predominantly a changed position of the stops for positioning the disc. In addition to a separate conversion can This can also be achieved by attaching to a main body of the Robot gripper different for different discs set stops are arranged, each of which is not Required attacks in a non-interfering when gripping Be pivoted position. However, this change requires which can only be partially automated, also a certain Time. In addition, with the pre-set stops Tolerances of the disc dimensions can not be compensated.

DE 202 21 729 U1 describes a device for gripping, for example, motor vehicle windows or body parts by means of a robot arm. This robot gripper consists of a carrier with suction pads, each having an elastic absorbent body. The absorbent body is placed on the object to be gripped and subjected to negative pressure. Furthermore, at least one stop is provided, which determines the position of the gripped object and which is arranged in the gripping direction relative to the carrier displaceable. The stop is associated with a clamping device with which the stop is fixed against the gripping direction after a fixed stroke. The at least one stop is arranged within a suction body and is enclosed by this. The stops automatically adapt to the respective contour of the object to be gripped by first moving slightly in contact with the object in the direction of the carrier and only then being clamped after the robot gripper has reached a defined transfer position. This ensures that the stops touch the object before it is applied with negative pressure, so that an unintentional deformation of the object is avoided. However, a disadvantage of this robotic gripper is the difficult and expensive assembly, because the guide body is designed in two parts and the clamping device is in the overlap of the two parts.

Despite the already known technical solutions, there is still a need for development, resulting in particular from increasingly shorter Taktzei results in the vehicle assembly and the same time increasing quality specifications in terms of installation accuracy.

task the invention is to provide a technical solution with the one for the automated assembly of two together necessary to be joined components relative position Consideration of component tolerances in a short time and high accuracy can be adjusted. In particular, should an application for joining operations in the Automotive industry, primarily for the assembly of Vehicle windows in motor vehicle bodies allows become.

These The object is achieved in that a robot arm is a carrier assembly with suckers and stops first in a measuring position moved above an object to be gripped, then that the concrete storage position of the object to be gripped with several Camera systems is determined, based on the case determined Data a possibly necessary correction of the position of the robot gripper takes place that subsequently the object to be gripped with the attacks fixed in position, raised with the suckers and through the moved from the robot arm carrier assembly in front of a with the Object to be equipped section of another assembly becomes that after that the concrete relative position of object and Assembly is determined with multiple camera systems, where on Basis of the data determined in this case may be necessary again Correction of the position of the robot gripper takes place subsequently the article is mounted to an associated section of the assembly or inserted into an assigned section of the module and that after joining the position of the object measured with respect to the assembly with multiple camera systems is based on the data thus obtained a rating the process control with a statement "OK" or "NOT OK.

For the application of this method is a robotic gripper suitable which has a base frame, on which several suckers, several hold-down supported with Andruckpins and several camera systems, taking the suckers and the Andruckpins, each in the direction of are designed to be gripped object to be gripped, each locking units are assigned, based on the determined by the camera systems Coordinates can be actuated via a controller.

advantageous Embodiments are each subject of dependent Claims whose technical characteristics in the embodiment be explained in more detail.

With The proposed technical solution may be one for the automated assembly of at least two to be joined together Components required relative position, taking into account Component tolerances with little time and high accuracy be set. This technical solution is for various applications suitable, a preferred application Here is the installation of vehicle windows in motor vehicle bodies on production lines of the automotive industry.

By the displacement of the suckers and Andruckpins relative to the base frame it is possible to use the camera systems permanently installed on the base frame with the robotic arm for different discs in different To drive measuring positions. Thus, the field of view of the cameras in the delivery direction are variably positioned. At the same time sucked in the different positions a vehicle window become. This disc is then on the absorbent bodies of Suction cups and on the crests of Andruckpins the hold-down. Thereby is a strain of the disc by external force avoided. In this position, the axially movable components the nipple and Andruckpins clamped. Through this type of disc recording is a stable recording of the vehicle window for the following Glue application and the installation of the disc in the body ensured.

One Embodiment of the invention is in the drawing and will be described below. Show it:

1 a robot gripper in perspective view

2 according to the robot gripper 1 in plan view

3 according to the robot gripper 1 in front view

4 a sectional view taken along the line AA in 2

5 a sectional view taken along the line BB in 2

The robot gripper shown in the drawing consists of a carrier assembly serving as a base frame 1 is designed. This basic frame 1 is attached to a - not shown in the drawing - robot arm and can be moved with this robot arm in several degrees of freedom. At the base frame 1 are several suckers 2 , several hold-downs 3 with pressure pins 4 and several camera systems 5 supported. The robot arm and these assemblies are from a Anla controlled gene control, wherein in the illustrated embodiment, six suckers 2 and hold down 3 as well as four camera systems 5 are provided.

The suckers 2 and the Andruckpins 4 are in the direction of the object to be gripped, for example, a vehicle window for motor vehicle bodies displaced. The suckers can do this 2 and Andruckpins 4 be firmly clamped with a respective associated locking unit in a selectable position, wherein the locking units are not shown in the drawing. The locking position of Andruckpins 4 depends on the specific application. The locking units are based on the camera systems 5 determined coordinates are actuated via a controller.

The suckers 2 are each with an elastic absorbent body 6 equipped, this absorbent body 6 are placed on the object to be gripped and subjected to negative pressure. This is the suckers 2 one vacuum unit each 7 assigned.

An advantageous embodiment provides that the robot gripper has two separate suction circuits each with a separate vacuum monitoring. Thus, a part of the suckers 2 one suction circuit and the other part of the vacuum cleaner 2 be assigned to the other absorption circuit. In this case, the robot gripper preferably has an even number of suckers 2 on, of which in each case a half number is assigned to the first and the second absorption circuit. In the illustrated embodiment with a total of six suckers 2 Consequently, each suction circuit would each three suckers 2 assigned.

For the camera systems 5 Different variants are possible, wherein primarily a design is proposed as an optical or laser-based surveying system.

The basic frame 1 can also be configured differently. In a preferred variant according to the embodiment shown, such a base frame 1 from several lightweight profiles 8th joined together, which are each arranged at right angles to each other. In the transition areas between two adjacently arranged lightweight profiles 8th can each have a reinforcing element on the inside of the frame contour 9 to be ordered. As a result, a simple production and high dimensional stability of the entire base frame 1 reached. The items of the base frame 1 and those on the base frame 1 Supported assemblies are preferably assembled with cylinder screws to the actual robot gripper, with no reference numerals are entered for related fasteners in the drawing.

The basic frame 1 has a centering ring 10 for the associated robot arm. This centering ring 10 is on a flange plate 11 arranged over other lightweight profiles 12 or via a mounting plate 13 on the outside arranged lightweight profiles 8th of the basic frame 1 is supported.

The described robot gripper can be configured differently. For example, in the transition area of centering ring 10 and robotic arm a capacitive sensor 14 to be ordered. Furthermore, on the base frame 1 a plate 15 be arranged for a measuring point for controlling the position of the individual elements.

In the illustrated embodiment of the base frame 1 with lightweight profiles 8th and 12 become the suckers 2 and the hold-downs 3 with the Andruckpins 4 led in recesses in the existing example of aluminum lightweight profiles 8th respectively. 12 are configured on the side surfaces which are arranged approximately at right angles to the base surface of the object to be gripped.

The camera systems 5 are stored so that the outer contours of the objects to be gripped (vehicle windows) in the measuring window / measuring volume of the camera system 5 lie. In recesses of the lightweight profiles 8th becomes a flange clamp 16 with a console 17 led, at the a tubular holder 18 for the camera system 5 is supported.

When operating such a robot gripper, the robot arm first moves the base frame 1 in a measuring position above the object to be gripped, so for example above a front or rear window for a motor vehicle. Automated assembly is supported by an optical or laser-based surveying system. The disc recognition takes place by means of initiators and the concrete storage position of the vehicle window becomes with the camera systems 5 determined. On the basis of the determined data the position of the robot gripper is corrected if necessary.

Then the vehicle window with the Andruckpins 4 the hold down 3 fixed in position and with the absorbent bodies 6 the sucker 2 raised. There are only such Andruckpins 4 and absorbent body 6 activated, which are necessary for a position-stable gripping of the respective vehicle window depending on their particular concrete contour.

Below is the base frame moved by the robot arm 1 placed in front of a to be equipped with the vehicle window cutout of a body. Now, the current relative position of the vehicle window and body cutout with the camera systems 5 determined. If necessary, a correction of the position of the robot gripper takes place on the basis of the data determined here.

Subsequently, the vehicle window is inserted in the associated section of the body. After this joining process, the position of the vehicle window with respect to the body with the camera systems 5 measured. On the basis of the data determined in this case, an evaluation of the process control is concluded with a statement "OK" or "NOT OK".

1

base frame

2

sucker

3

Stripper plate

4

Andruckpins

5

camera system

6

suction body

7

vacuum unit

8th

lightweight profile

9

reinforcing element

10

centering

11

flange

12

lightweight profile

13

mounting plate

14

capacitive sensor

15

plate for measuring point

16

Flange Clamp

17

console

18

bracket

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 3716232 C2 [0004]
• - DE 29712202 U1 [0005]
• - DE 20221729 U1 [0008]

Claims (14)

A method of operating a robotic gripper comprising a support assembly secured to and movable from a plurality of degrees of freedom of movement of the robotic arm, the support assembly having a plurality of aspirators, each fitted with an elastic absorbent body, mounted on the object to be gripped and subjected to negative pressure and wherein at least one stop is provided which is displaceable in the gripping direction relative to the support assembly and by means of a clamping device in a defined position, characterized in that the robot arm first moves the support assembly in a measuring position above an object to be gripped, that thereafter the concrete storage position of the object to be gripped is determined with a plurality of camera systems, wherein on the basis of the data determined in this case a possibly necessary correction of the position of the robot gripper takes place, that subsequently to grasp the Fixed object with the stops in place, lifted with the suckers and placed by the robotic arm moving carrier assembly in front of an object to be equipped with the section of another assembly, that thereafter the concrete relative position of the object and assembly is determined with multiple camera systems, On the basis of the data determined in this case, a possibly once again necessary correction of the position of the robot gripper takes place, that subsequently the object is mounted on an assigned section of the assembly or inserted into an associated section of the assembly and that after the joining the position of the object with respect to the assembly is measured with a plurality of camera systems, wherein on the basis of the data thus obtained, an evaluation of the process control is made with a statement "OK" or "NOT IN ORDER". Method according to claim 1, characterized in that that the robot gripper applied for assembly operations is, in particular for joining slices in cutouts of motor vehicle bodies in the automotive industry. A robotic gripper for an application of the method according to claim 1, comprising a carrier assembly which is mounted on a robot arm and can be moved by the latter in multiple degrees of freedom, wherein the carrier assembly comprises a plurality of suckers, each equipped with an elastic absorbent body, which on the to be gripped object, in particular a disc for motor vehicles, placed and subjected to negative pressure and wherein at least one stop is provided, which is displaceable in the gripping direction relative to the carrier assembly and lockable by means of a clamping device in a defined position, characterized in that the robot gripper a base frame ( 1 ), on which several suckers ( 2 ), several hold-downs ( 3 ) with Andruckpins ( 4 ) and several camera systems ( 5 ), whereby the suckers ( 2 ) and the Andruckpins ( 4 ), which are each designed to be displaceable in the direction of the object to be gripped, in each case locking units are assigned which, starting from the camera systems ( 5 ) coordinates can be actuated via a controller. Robot gripper according to claim 3, characterized in that the robot gripper has two separate suction circuits each with a separate vacuum monitoring, wherein a part of the suckers ( 2 ) one suction circuit and the other part of the suction device ( 2 ) is assigned to the other absorption circuit. Robot gripper according to claim 4, characterized in that the robot gripper has an even number of suckers ( 2 ), of which in each case a half number is assigned to the first and the second absorption circuit. Robot gripper according to claim 3, characterized in that the camera systems ( 5 ) are stored such that the outer contours of the objects to be gripped in the measuring window / measuring volume of the camera system. Robot gripper according to claim 3, characterized in that the camera systems ( 5 ) are designed as optical surveying system. Robot gripper according to claim 3, characterized in that the camera systems ( 5 ) are designed as a laser-based surveying system. Robot gripper according to claim 3, characterized in that the base frame ( 1 ) made of lightweight profiles ( 8th ; 12 ) is arranged, which are each arranged at right angles to each other and which in the transition areas between two adjacently arranged lightweight profiles ( 8th ; 12 ) on the inside of the contour of the base frame ( 1 ) each have a reinforcing element ( 9 ) assigned. Robot gripper according to claim 9, characterized in that the base frame ( 1 ) a centering ring ( 10 ) for the associated robot arm, wherein the centering ring ( 10 ) on a flange plate ( 11 ), which have lightweight profiles ( 12 ) and / or via a mounting plate ( 13 ) on the externally arranged lightweight profiles ( 8th ) of the basic frame ( 1 ) is supported. Robot gripper according to claim 10, characterized in that in the transition region of the centering ring ( 10 ) and robotic arm a capacitive sensor ( 14 ) is arranged. Robot gripper according to claim 9, characterized in that on the base frame ( 1 ) a plate ( 15 ) is arranged for a measuring point for controlling the position of the individual elements of the robot gripper. Robot gripper according to claim 9, characterized in that the suckers ( 2 ) and the hold-downs ( 3 ) with the Andruckpins ( 4 ) are stored in recesses which are in the lightweight profiles ( 8th ; 12 ) are configured on the side surfaces which are arranged approximately at right angles to the base of the object to be gripped. Robot gripper according to claim 9, characterized in that in recesses of the lightweight profiles ( 8th ) a Flanschklemmstück ( 16 ) with a console ( 17 ) is guided on which a tubular holder ( 18 ) for a camera system ( 5 ) is supported.