DE202015004398U1 - Mobile manipulator system with monitoring system - Google Patents

Abstract

A mobile manipulator system (1) comprising: at least one manipulator (20) controlled by a control device (30); at least one mobile platform (10) on which the manipulator (20) is arranged; a monitoring system (100; 200; 300) for detecting movement of the mobile platform (10), the monitoring system (100; 200; 300) comprising: at least one sensor (140; 240; 340) attached to the mobile platform or is arranged on the manipulator, wherein the sensor is adapted to detect a movement of the mobile platform (10), at least one monitoring logic (101; 202; 303) which is adapted to receive a sensor signal and to generate an output signal indicating in that a movement of the mobile platform (10) has taken place.

Description

Field of the invention

The invention relates to mobile manipulator systems comprising at least one manipulator and a mobile platform, further providing a monitoring system configured to detect movement of the mobile platform.

Background of the invention

Mobile manipulator systems typically include a mobile platform and a manipulator. For example, a mobile manipulator system may be a LBR iiwa Springer of KUKA AG. A manipulator is a device that enables physical interaction with the environment. In particular, the manipulator may be an industrial robot, wherein an industrial robot is an automatically guided multipurpose manipulator equipped with three or more freely programmable axes of motion used in industrial applications. Typically, such manipulators carry grippers, tools or workpieces. To be able to guide grippers, tools or workpieces exactly, the position and orientation of the manipulator in the manipulator system must be known.

If the manipulator is attached to a mobile platform, it can be used in mobile applications in industrial applications. For example, a mobile platform may comprise a linear axis, thus enabling movement of the manipulator in at least one coordinate direction. Likewise, a mobile platform can be moved in two directions, for example by combining two linear axes. Furthermore, it is possible that the mobile platform can be moved freely on one level. In this case, the mobile platform is typically equipped with wheels.

A mobile platform can be automated or moved manually. If the mobile platform is operated automatically, then it can be driven, for example, via electric motors, pneumatic motors, hydraulic motors or the like. If the mobile platform is operated manually, the mobile platform can be pushed to the place of use, for example, via castors and fixed castors. Likewise, the mobile platform may have other known roles and / or wheel shapes.

To be fixed in place at the job site, the mobile platform typically has at least one brake that can block the movement of the mobile platform. Such a brake can for example be operated manually or via a corresponding actuator, such as an electric motor, a lifting cylinder or the like are operated. A corresponding brake can act on a wheel of the mobile platform or on all wheels of the mobile platform. Preferably, the mobile platform can be fixed by pressing a brake switch, brake lever or the like.

The stationary fixation of the mobile platform at the site is important because the manipulator must be referenced to determine the position and orientation of the manipulator in the manipulator system. If, for example, workpieces are to be gripped and positioned, then the manipulator must be able to approach the position of the workpieces exactly. If the mobile platform on which the manipulator is located now moves, the position of the manipulator changes, with the result that the manipulator would subsequently operate with an unknown offset.

From the prior art solutions are known according to which mobile platforms are rigidly connected to other structures in order to keep their position constant. However, there is still the problem that a still occurring movement of the mobile platform is not recognized. If such a movement remains unrecognized, the manipulator would, for example, not grasp or position workpieces which it grips, should position, or position with an unknown offset and / or orient. This may result in disruption to the production process or even damage to objects and / or people. It is therefore an object of the present invention to overcome the disadvantages mentioned.

Detailed description of the invention

The object is achieved by a mobile manipulator system according to claim 1.

In particular, the object is achieved by a mobile manipulator system comprising: at least one manipulator which is controlled by a control device; at least one mobile platform on which the manipulator is arranged; a monitoring system for detecting movement of the mobile platform, the monitoring system comprising: at least one sensor disposed on the mobile platform or on the manipulator, the sensor configured to detect movement of the mobile platform; and at least one monitoring logic configured to receive a sensor signal and generate an output signal indicating that movement of the mobile platform has occurred.

If a monitoring system for detecting a movement of the mobile platform is provided, then it can be detected whether a movement of the mobile platform has taken place. Thus, errors that are due to an unwanted movement of the mobile platform can be avoided. The at least one sensor may be, for example, an optical sensor, a magnetic sensor or an acceleration sensor. In principle, any sensor capable of detecting a change in position, a change in speed and / or an acceleration is suitable.

If an output signal is generated based on a sensor signal, which indicates that a movement of the mobile platform has taken place, a control device of the manipulator can start safety-relevant modes, for example. Preferably, the monitoring system is activated when the mobile platform is positioned at a destination where the manipulator is to be deployed. The monitoring system may include both hardware and software. At the destination, the manipulator is typically referenced. The reaching of the destination can be detected, for example, by detecting a brake of the mobile platform. Likewise, the beginning of the referencing of the manipulator can indicate that the destination has been reached. Other inputs indicating that the destination of the mobile platform has been reached are also conceivable, for example an operator may manually confirm that the destination has been reached.

By way of example, after reaching the destination, a button can be activated which indicates that the destination has been reached. Subsequently, a brake which acts, for example, on a wheel of the mobile platform, fix the mobile platform stationary.

After activating the monitoring system, the sensor cyclically monitors whether the mobile platform is moving. When a movement is detected, a signal indicating that movement has occurred is generated. Alternatively, a release signal may be provided if no movement of the mobile platform has been detected. For example, a release signal may allow movement of the manipulator.

Preferably, the control means is arranged to stop the manipulator if the output signal indicates that movement of the mobile platform has taken place. Stopping the manipulator after detecting movement of the mobile platform prevents possible damage in the production process and / or on the workpieces. In particular, damage to persons located in the vicinity of the manipulator can be avoided. In particular, when a manipulator of a mobile manipulator system is operated without a safety fence, the detection of movement of the mobile platform is important. Typically, in these applications, the work area of the robot is monitored with sensors. As the mobile platform shifts, the robot's workspace also shifts so that part of the displaced workspace may no longer be monitored. This creates potential hazards to surrounding objects and people. Therefore, stopping the manipulator after detecting movement of the mobile platform is advantageous to prevent damage.

Preferably, the at least one sensor is an optical sensor and more preferably a camera. An optical sensor is advantageous since existing objects can be detected and evaluated with an optical sensor. If the optical sensor is a camera, for example, the evaluation of the image data can reveal that a movement of the mobile platform has taken place. Preferably, the optical sensor is directed to a wheel of the mobile platform, wherein the optical sensor is further configured to cyclically detect at least a portion of the wheel.

If the optical sensor is directed, for example, to a wheel of the mobile platform, it can be determined by a cyclic comparison of the sensor data whether a wheel is moving. If the recorded image data changes, it can be assumed that the wheel has moved. Preferably, a typical pattern is applied to the wheel, such as a profile. If the optical sensor is configured to recognize the pattern, then it can be evaluated from a comparison of at least two consecutively recorded optical sensor data as the mobile platform has moved. When multiple wheels of the mobile platform are monitored with an optical sensor, information about the distance of the movement of the mobile platform and the direction of movement of the mobile platform can be obtained. This allows, for example, an adaptation of the referencing of the manipulator, which is arranged on the mobile platform.

Preferably, the optical sensor is directed to an object in the vicinity of the mobile platform, wherein the object is preferably the ground, and wherein the optical sensor is further configured to cyclically detect at least a portion of the environment. If the optical sensor is directed towards the surroundings, a movement of the mobile platform can be detected by a comparison of the optical sensor data. A comparison of optical sensor data, with reference to the For example, it is advantageous if the mobile platform is to be used in a dusty environment. In such an application scenario, dust can be whirled up by the wheels and thus a reliable detection and / or evaluation of the sensor data can be made more difficult if the sensor is aimed at one of the wheels. If the optical sensor is aimed at an object in the environment, the sensor can be better protected against possible dirt, such as dust.

Preferably, the at least one sensor is an acceleration sensor, wherein the acceleration sensor is adapted to detect accelerations of the mobile platform in at least one horizontal plane. If the detected accelerations exceed a defined threshold, it can be assumed that the mobile platform has been moved. In particular, acceleration sensors are advantageous because they can be completely surrounded by a housing and thus protected from environmental disturbances such as dirt, dust, moisture and the like.

Detailed description of the figures

The invention is described below by way of example with reference to the figures. Showing:

1 a mobile manipulator system;

2 a monitoring system comprising an optical sensor;

3 a monitoring system comprising a further optical sensor; and

4 a monitoring system comprising an acceleration sensor.

In particular shows 1 a mobile manipulator system 1 comprising a mobile platform 10 , a manipulator 20 and a controller 30 of the manipulator 20 , The mobile manipulator 20 For example, it may be configured to grip and position workpieces or objects in the environment. This is the mobile manipulator 20 on the mobile platform 10 arranged. The mobile platform 10 has at least two wheels 11 . 12 and can be manually pushed to a destination, for example. At this destination, the brakes (not shown) may be the wheels 11 . 12 block and so a movement of the mobile platform 10 prevent. To a possible movement of the mobile platform 10 To be able to detect, the sensor systems, as in the 2 . 3 and 4 are shown used.

2 shows a monitoring system 100 to detect a movement of the mobile platform 10 , Further shows 2 a spherical wheel or roller 111 a mobile platform, which by means of a brake 104 that have a motor 103 can be operated, can be determined. For detecting a movement of the mobile platform, for example, via the light source 120 which, for example, a laser diode can be light on the surface 130 of the wheel 111 blasted, which is an optical sensor 140 cyclically absorbs. The monitoring logic 101 , which may include hardware and / or software, receives the sensor signal of the sensor 140 and generates an output signal indicating whether movement of the mobile platform has taken place. This output signal can, for example, to a control device 102 be sent to the manipulator. The control device 102 preferably includes a safety controller that stops movement of the manipulator when movement of the mobile platform has been detected.

3 shows the monitoring system 200 , The monitoring system 200 includes a spherical wheel 211 the mobile platform 10 which wheel 211 by means of a brake 204 that have a motor 203 can be operated, can be determined. In order to detect a possible movement of the mobile platform, a light source emits light 220 , such as a laser diode on an object in the environment. The light is reflected by the object in the environment and by the optical sensor 240 detected. By a cyclic comparison of the recorded sensor data, a movement of the mobile platform can be detected. The sensor signal is from the monitoring logic 202 , which may include both software and hardware, converted to an output signal indicating whether movement of the mobile platform has taken place. If a mobile platform has taken place, for example, the control device 202 stop the movement of the manipulator.

4 shows a monitoring system 300 for detecting a movement of a mobile platform, wherein the mobile platform is a spherical wheel 311 includes, which via a brake 304 that of a motor 303 can be operated, can be determined. Furthermore, the monitoring system includes 300 an acceleration sensor 340 which is on the mobile platform 10 is appropriate. Detects the acceleration sensor 340 an acceleration that exceeds a threshold, it can be assumed that a movement of the mobile platform has taken place. When movement of the mobile platform is detected, the monitoring logic is generated 301 , which may include both software and hardware, an output signal. The output signal is sent, for example, to a control device 302 passed, which controls the manipulator. If a movement of the mobile platform detected, so the manipulator can be stopped, for example.

LIST OF REFERENCE NUMBERS

1

Mobile manipulator system

10

Mobile platform

11, 12

bikes

20

manipulator

30

control device

100, 200, 300

monitoring system

101, 201, 301

monitoring logic

102, 202, 303

control device

103, 203, 303

engine

104, 204, 304

brake

111, 211, 311

spherical wheel

120, 220

light source

140, 240

Optical sensor

340

accelerometer

Claims (6)

Mobile manipulator system ( 1 ), comprising: at least one manipulator ( 20 ), which is controlled by a control device ( 30 ) is controlled; at least one mobile platform ( 10 ) on which the manipulator ( 20 ) is arranged; a surveillance system ( 100 ; 200 ; 300 ), to detect movement of the mobile platform ( 10 ), the monitoring system ( 100 ; 200 ; 300 ) comprises: at least one sensor ( 140 ; 240 ; 340 ), which is arranged on the mobile platform or on the manipulator, wherein the sensor is adapted to a movement of the mobile platform (FIG. 10 ), at least one monitoring logic ( 101 ; 202 ; 303 ) adapted to receive a sensor signal and to generate an output signal indicating that movement of the mobile platform ( 10 ) has taken place. Mobile manipulator system ( 1 ) according to claim 1, wherein the control device ( 30 ) is adapted to the manipulator ( 20 ) if the output signal indicates that movement of the mobile platform ( 10 ) has taken place. Mobile manipulator system ( 1 ) according to one of the preceding claims, wherein the at least one sensor ( 100 ; 240 ) is an optical sensor and preferably a camera. Mobile manipulator system ( 1 ) according to claim 3, wherein the optical sensor is mounted on a wheel ( 11 . 111 . 211 ) of the mobile platform ( 10 ), and wherein the optical sensor is further adapted to at least a part ( 130 ) of the wheel ( 11 ; 12 ; 111 ) cyclically. Mobile manipulator system ( 1 ) according to claim 3, wherein the optical sensor is incident on an object in the environment of the mobile platform ( 10 ), wherein the object is preferably the bottom, and wherein the optical sensor is further adapted to at least a part ( 230 ) cyclically detect the environment. Mobile manipulator system ( 1 ) according to one of claims 1 or 2, wherein the at least one sensor ( 340 ) is an acceleration sensor, and wherein the acceleration sensor is adapted to accelerate the mobile platform ( 10 ) in at least one horizontal plane.

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