Device and Method for Gripping an Object

Abstract

A device for gripping an object includes a base element and at least two gripping arms held on the base element. The at least two gripping arms are movable relative to one another and the base element into a configuration suitable for gripping and picking up the object. Preferably at least three gripping arms are provided, with each arm being able to move independently of one another relative to the base element, and a sensor such as a camera provides signals to electronics which can determine the position of the at least three gripping arms and control movement of the gripping arms into position to grip and pick up the object. A method for gripping and picking up an object using the gripping device is also provided.

Claims

1-10. (canceled)

11. A device for gripping an object, comprising: a base element; and at least two gripping arms on the base element, the at least two gripping arms being configured to hold the object to be picked up, wherein at least three gripping arms are provided, which are each movable independently of one another relative to the base element.

12. The device according to claim 11, wherein the gripping arms are pivotable around respective axes of rotation relative to the base element.

13. The device according to claim 12, wherein the axes of rotation are arranged in parallel to one another.

14. The device according to claim 13, wherein at least one of the gripping arms incudes a translation adjustment unit and a gripping element held on the translation adjustment unit, the gripping element being movable relative to the translation adjustment unit.

15. The device according to claim 14, wherein the gripping element is movable along a longitudinal extension direction of the translation adjustment unit.

16. The device according to claim 14, wherein the gripping element is settable in its distance from the translation adjustment unit.

17. The device according to claim 14, wherein the gripping element is settable in its distance from the translation adjustment unit.

18. The device according to claim 17, wherein the gripping element includes a quick change unit configured to receive a gripping tool via a quick-action closure.

19. The device according to claim 18, further comprising a detection unit configured to determine from a sensor signal detection of the object to be gripped; an electronic processing unit configured to receive detected object information from the detection unit and ascertain a relative position of the object to be gripped relative to the gripping arms; and a control unit configured to control the movement of gripping arms relative to the object to grip the object based on the ascertained relative position.

20. The device according to claim 19, further comprising: a fastening unit configured to fasten the device on a robot.

21. A method for gripping an object, comprising the acts of: moving at least two gripping arms of at least three gripping arms held on a base element relative to the base element into a configuration at which the object may be gripped by the at least three gripping arms; and gripping the object with the at least three gripping arms, wherein the at least three gripping arms are each are configured to be moved independently of one another relative to the base element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 shows a perspective view of a robot having a device in accordance with an embodiment of the present invention for gripping a motor vehicle part, by means of which the motor vehicle part is picked up and which is adaptable to the motor vehicle part; and

[0018] FIG. 2 shows a perspective view of the device of FIG. 1 for gripping the motor vehicle part having three gripping arms flexibly movable relative to one another, by means of which a respective gripping tool, by means of which the motor vehicle part can be gripped particularly securely, can be received via a respective quick-action closure of a quick change unit.

DETAILED DESCRIPTION

[0019] Identical elements are provided with identical reference signs in the figures.

[0020] A robot 1 is shown in FIG. 1, by means of which a device 2 for gripping an object is accommodated. In the following, the device 2 is described in conjunction with picking up a motor vehicle part 3 as the object. The device 2 is movable relative to the motor vehicle part 3 by means of the robot 1 to enable the device 2 to be applied to the motor vehicle part 3. The robot 1 can be used, for example, in a production facility for motor vehicles, in particular automobiles, wherein the motor vehicle part 3 is gripped by means of the device 2, the device 2 is moved by means of the robot 1, and subsequently the motor vehicle part 3 is released by means of the device 2, by which the motor vehicle part 3 is transportable from a first location to a second location.

[0021] The device 2 is shown in more detail in FIG. 2. It can be recognized here that the device 2 comprises a base element 4 and three gripping arms 5 held on the base element 4. The gripping arms 5 are held on the base element 4 so they are movable relative to the base element 4. In the present case, the gripping arms 5 are pivotable around respective axes of rotation 6 aligned in parallel to one another independently of one another relative to the base element 4 in a shared movement plane. The device 2 comprises rotation units 15 assigned to the respective gripping arms 5, via which the gripping arms 5 are pivotable around the axes of rotation 6 relative to the base element 4. The rotation units 15 are respective turntables in the present case. In this way, the gripping arms 5 can be adjusted relative to one another in an optimum angle. In the present case, a separate axis of rotation 6 is assigned to each of the gripping arms 5. In an alternative embodiment (not shown), the axes of rotation 6 can coincide with one another.

[0022] In the present case, each of the gripping arms 5 comprises a translation adjustment unit, which in the present case is a rail 7, and a gripping element 8 held on the rail 7. The rails 7 extend in the present case perpendicularly to the respective axis of rotation 6. The rails 7 provide respective traversing axes for the gripping elements 8. This means that the respective gripping elements 8 are movable along a longitudinal extension direction of the respective rails 7 relative to the rails 7. In the present case, two of the three gripping arms 5 comprise a vertical adjustment unit 9, by means of which a distance between the respective gripping elements 8 and the associated rails 7 of the respective gripping arms 5 is settable. In the present case, an adjustment direction of the vertical adjustment unit 9 extends in parallel to the respective assigned axes of rotation 6 of the respective gripping arms 5. Via the respective vertical adjustment units 9, the gripping elements 8 can be moved toward the rail 7 or can be moved away from the respective assigned rail 7.

[0023] To be able to adapt the device 2 particularly advantageously to the respective motor vehicle part 3 to be picked up, the respective gripping elements 8 each comprise a quick change unit 10. The quick change unit 10 is configured to receive a gripping tool adapted to the respective motor vehicle part 3 to be picked up via a quick-action closure. Receiving the respective gripping tool adapted to the motor vehicle part 3 to be gripped enables particularly rapid and simple adaptation of the device 2 to the motor vehicle part 3 by a selection of the respective gripping tools assigned to the motor vehicle part 3.

[0024] To be able to receive the device 2 by means of the robot 1, the device 2 comprises a fastening unit 11, which is schematically identified in the present case by a box. The device 2 is fastenable on the robot 1 and is to be held on the robot 1 via the fastening unit 11. The fastening unit 11 thus enables particularly secure and simple fastening of the device 2 on the robot 1, so that the device 2 is movable relative to the motor vehicle part 3 to be gripped by means of the robot 1. The fastening unit 11 can be designed as an automatic docking system for an automated tool change on the robot 1.

[0025] To enable particularly precise gripping of the motor vehicle part 3 by means of the device 2, in the present case the device 2 comprises a detection unit 12. This detection unit 12 comprises a camera unit in the present case. The detection unit 12 enables positioning of the device 2 relative to the motor vehicle part 3 by means of a camera object recognition. An image of the motor vehicle part 3 is recordable by means of the camera unit. The detection unit 12 provides a sensor signal characterizing the image for an electronic processing unit 13 of the device 2. The received sensor signal can be evaluated by means of the electronic processing unit 13. As a result of the evaluation of the sensor signal, a relative position of the device 2, in particular of the gripping arms 5, relative to the motor vehicle part 3 can be ascertained. The electronic processing unit 13 provides the ascertained relative position for an electronic control unit 14 of the device 2. By means of the control unit 14, which is schematically identified like the electronic processing unit 13 by a box, the gripping arms 5 are movable relative to the base element 4. As a result of the reception of the relative position of the device 2 or the gripping arms 5 in relation to the motor vehicle part 3 to be gripped, the gripping arms 5 are moved by means of the electronic control unit 14 in dependence on the ascertained relative position in relation to the motor vehicle part 3 to be able to pick up the motor vehicle part 3 particularly precisely. In this case, during a movement of the gripping arms 5 relative to the base element 4 or relative to the motor vehicle part 3, the motor vehicle part 3 can be recorded repeatedly at regular intervals by means of the detection unit 12. This enables respective relative positions of the device 2 or the gripping arms 5 assigned to the recordings of the motor vehicle part 3 in relation to the motor vehicle part 3 to be able to be ascertained by means of the electronic processing unit 13. In dependence on the multiple ascertained relative positions, which have been ascertained relative to one another at time intervals, the movement of the gripping arms 5 relative to the motor vehicle part 3 can be adapted and thus corrected by means of the electronic control unit 14. In this way, the motor vehicle part 3 can be picked up particularly precisely by means of the device 2. Alternatively or additionally, the relative position of the device 2 or the gripping arms 5 in relation to the motor vehicle part 3 ascertained by means of the electronic processing unit 13 can be provided for a further electronic control unit, wherein the robot 1 is controllable by means of the further electronic control unit in order to align the device 2 relative to the motor vehicle part 3 in dependence on the ascertained relative position.

[0026] The described device 2 and the described method for gripping the motor vehicle part 3 by means of the device 2 is based on the knowledge that due to a high degree of automation in vehicle body construction, a variety of gripping systems is used to grip motor vehicle parts 3. Many of these gripping systems only have comparatively little flexibility. The device 2 creates an option of gripping a broad spectrum of motor vehicle parts 3, including assemblies in the vehicle construction, particularly advantageously. For this purpose, a three-dimensional movement of the gripping arms 5 relative to the respective motor vehicle part 3 to be gripped is possible by means of the device 2. This allows the motor vehicle component 3 to be able to be gripped independently of features or depending on features by means of the device 2.

[0027] Overall, the invention shows how a flexible gripping system having gripping arms 5 which can be particularly flexibly actuated three-dimensionally can be provided.

LIST OF REFERENCE NUMERALS

[0028] 1 robot [0029] 2 device [0030] 3 motor vehicle part [0031] 4 base element [0032] 5 gripping arm [0033] 6 axis of rotation [0034] 7 rail [0035] 8 gripping element [0036] 9 vertical adjustment unit [0037] 10 quick change unit [0038] 11 fastening unit [0039] 12 detection unit [0040] 13 electronic processing unit [0041] 14 electronic control unit [0042] 15 rotation unit