DE102010046327A1 - Method for monitoring mobile robot, involves arranging mirror before monitoring unit, and monitoring one of safety surfaces different from each other in operating mode of manipulator by monitoring device - Google Patents

Abstract

The method involves arranging a mirror (4) before a monitoring unit i.e. laser scanner (3). One of safety surfaces different from each other is monitored in an operating mode of a manipulator by a monitoring device, where the safety surfaces differ in orientation, contour and/or dimensions. The operating mode of the manipulator is executed depending on a monitored safety field. A multi-axle articulated arm (1) of the manipulator is present in the operating mode within a working area defined by the monitoring unit and moved into another operating mode from the working area. An independent claim is also included for a mobile manipulator i.e. robot, including a monitoring device.

Description

The present invention relates to a method for monitoring a manipulator, in particular a robot, with a mobile base, as well as a mobile manipulator with a monitoring device, which is set up to carry out such a method.

Mobile manipulators such as Applicant's OmniRob mobile robot are often equipped with laser scanners that monitor a horizontal security area. The horizontally emitted beams of the laser scanners cycle over the horizontal safety surface. If an obstacle is detected in this, a suitable reaction can be carried out. For example, the mobile base of the manipulator can be re-navigated or stopped to avoid a collision. Similarly, it is also possible, especially on a stagnant basis, to perform an emergency stop when an obstacle is detected in the safety area so as to prevent endangering persons approaching the manipulator while standing on a stationary base.

The monitoring of a security area that is tuned for a particular operating mode, such as a free-wheeling or stationary mobile manipulator, is problematic in other situations, such as a manipulator operating in a confined environment.

The object of the present invention is to improve the monitoring of a mobile manipulator.

This object is achieved by a method having the features of claim 1. Claim 12 protects a mobile manipulator, which is set up to carry out a method according to the invention. The subclaims relate to advantageous developments.

A mobile manipulator in the sense of the present invention preferably has at least one tool or tool flange which, in particular by means of an arm with one or more actuated joints, in particular rotary joints, is movable relative to a base, which in turn is in an environment, in particular by means of wheels, caterpillars, air cushions, rails, portals or the like, is movable.

A monitoring device monitors a first safety surface in a first operating mode of the manipulator. In particular, the monitoring device can have one or more non-contact, in particular optical, monitoring means, wherein preferably each monitoring means monitors a region of a safety surface, which can thus be composed of several (partial) regions. In a preferred embodiment, a monitoring means to a laser scanner, which can monitor a security area, for example, it cyclically leaves. For this purpose, the laser scanner can likewise have a movable laser head, in particular pivotable about one or more axes, and / or optics which are preferably adjustable by one or more axes, in particular one or more pivotable deflecting mirrors. Additionally or alternatively, one or more monitoring means may also comprise other means for detecting an obstacle in a security area, for example light barriers, capacitive or ultrasonic sensors, image evaluations or the like.

According to the invention, in a second operating mode of the manipulator, this monitoring device monitors a second safety surface which is different from the first, which can differ from the first safety surface, at least in regions, in particular in its orientation, contour and / or extent. In a preferred embodiment, one of the security areas or a portion of this security area is oriented, at least substantially, horizontally, while another security area or a portion of this security area is oriented, at least substantially, vertically.

With an at least substantially horizontal safety surface, an obstacle approaching the manipulator can be detected and reacted in the usual way in a free-moving or stationary mobile manipulator. If the manipulator moves, it can, for example, be navigated around the obstacle. If the manipulator is free in its environment, an emergency stop can be carried out in order to avoid any danger to the approaching obstacle by the acting manipulator. It is clear that the safety surface preferably extends horizontally, for example near the bottom, but can also be inclined and / or curved against the horizontal in order to improve, for example, the actuation of the monitoring device, such as the pivoting of a laser scanner.

If, on the other hand, the manipulator is located in a limited environment which would be recognized as an obstacle in a horizontal safety surface, an at least essentially vertical safety surface can be monitored according to the invention which, in a preferred embodiment, partially or completely envelops the mobile manipulator. This will only break through this vertical safety curtain and thus a monitored direct penetration into the working area of the manipulator, while non-dangerous, especially static obstacles that limited the environment in which the mobile manipulator is located, are not detected.

Again, it is clear that this safety surface preferably extends vertically, but may also be inclined and / or curved against the vertical, for example, to improve the actuation of the monitoring device, such as the pivoting of a laser scanner. It will also be appreciated that a vertical safety surface can be used even with a free-standing manipulator, if it is provided that the manipulator moves only within a working space, which is limited by monitoring means of the monitoring device. For example, if two or more monitoring means, which are arranged on the outer edge of a base area of the mobile base and monitor a vertical security area, a working space that extends vertically above the base area, this vertical security area can be used to secure the manipulator against collisions as long as his tool and his movable against the base members are located within this working space.

Accordingly, two modes of operation, which according to the invention are assigned different security surfaces, differ in particular in that the base of the mobile manipulator moves in one operating mode in one environment and in the other operating mode relative to the environment. In the operating mode in which the base of the mobile manipulator moves in the environment, the monitoring device preferably monitors a safety surface that is wholly or partially, at least substantially, horizontally oriented, and in the operating mode in which the base is located, a safety surface, which is wholly or partially oriented, at least substantially, vertically oriented.

Additionally or alternatively, two modes of operation, which are assigned according to the invention different security surfaces, in particular differ in that one or more members, in particular a tool, the manipulator remain in an operating mode within a working space limited by monitoring means of the monitoring device, and in the other mode of operation exit this workspace. In the operating mode in which at least one member, in particular the tool, of the manipulator exits from this working space, the monitoring device preferably monitors a safety surface which is wholly or partially oriented, at least essentially, horizontally oriented, and in the other operating mode a safety surface which wholly or partially, at least substantially, is vertically oriented.

Additionally or alternatively, two modes of operation, which are assigned according to the invention different security areas, differ in particular in that the mobile manipulator is free in one operating mode in one environment or drives and is limited in the other mode of operation by the environment. Preferably, in the operating mode in which the mobile manipulator is standing or driving freely in the environment, the monitoring device monitors a security area that is wholly or partially, at least substantially, horizontally oriented, and in the other operating mode a security area that is entirely or partially , at least substantially, is vertically oriented. In this case, a restriction by the environment is understood in particular to mean a situation in which one or more, preferably stationary, environmental elements are within a predetermined minimum distance from the manipulator, in particular its base. The minimum distance may preferably be predetermined by the, in particular horizontal, action radius of the stationary manipulator.

In addition or as an alternative to one of the above-described changes between vertically and horizontally oriented safety surfaces or safety surface areas, it can be provided that in an operating mode a safety surface is monitored which is completely or partially oriented at least essentially vertically and a working space, which is preferably vertically above extends a base of the mobile base, substantially completely vertically encloses, while in another mode of operation, a security surface is monitored, which is also fully or partially oriented at least substantially vertically, but the working space is not completely vertical encloses, but has one or more recesses and thus additionally or alternatively to their orientation differs in their contour or extent. In particular, two operating modes, which according to the invention are associated with such different safety surfaces, differ in that one or more members, in particular a tool, of the manipulator remain in an operating mode within a limited by monitoring means of the monitoring device working space, and in the other operating mode from this working space escape. Preferably, the monitoring device then monitors in the operating mode in which at least one member, in particular the tool, the manipulator exits from this working space, a safety surface that does not completely surround the working space vertically, and in the other Operating mode, a safety surface that encloses the working space substantially completely vertically. This allows a scheduled escape of the manipulator member from the working space through a recess in the safety surface. A recess can be open-edge or closed. In particular, it can be realized in that a monitoring device does not monitor the cutout area and / or an object within the cutout is not registered or evaluated as a violation of the security area, but is ignored.

The selection of the security area may equally be cumulative, alternative, disjunctive, or otherwise logically related. For example, a security area can be monitored, which is entirely or partially, at least substantially, vertically oriented, if the mobile manipulator is stationary and is restricted by the environment. Similarly, a security area can be monitored, which is wholly or partially oriented, at least substantially, horizontally, if the mobile manipulator drives, is in a free environment and / or at least one limb of the manipulator exits from the limited by monitoring means of the monitoring device working space. In this respect, various of the operating modes explained above can be cascaded by differentiating within an operating mode, such as "standing" or "driving", into further operating modes, for example "within the work space" or "outside the work space".

In general, therefore, it can be provided that the monitoring device, in a third operating mode of the manipulator, monitors the first safety surface, the second safety surface or a third safety surface that is different from the first and second safety surfaces.

According to a preferred embodiment, optionally a deflection means, in particular a mirror, is arranged in front of at least one monitoring means, in particular a laser scanner, in order to monitor different security surfaces. In this way, it is possible to switch between different security surfaces in a simple, mechanical manner by arranging the deflection means in front of the monitoring means or by removing, in particular swinging it away. The deflecting means can be adjusted, for example, by an electric motor, electromagnetically, hydraulically and / or pneumatically, wherein in a preferred embodiment an excellent position is provided, into which the deflecting means is transferred when an energy supply ceases. For example, a mirror may be biased by a spring means into a position pivoted away from a monitoring means and actively transferred, for example by a servo motor or magnet, to a position pivoted in front of the monitoring means, so that it always swings away in the event of failure of the servo motor or magnet Takes position. Equally, it is also possible to reorient the deflection means itself, for example to adjust a laser head and / or a laser optics of a laser scanner accordingly.

Preferably, a deflection means is designed such that the monitored by the monitoring means security surface is transformed by the deflection into another security surface, in particular folded. Thus, for example, a correspondingly shaped, in particular three-dimensional deflecting mirror can fold a horizontal safety surface into a vertical safety surface if it is arranged in front of a laser scanner which emits horizontal beams. In particular, a transition region, preferably a vertical edge, can be produced in the vertical safety surface by means of a deflection means, in which two vertical safety surface regions, which enclose an angle with one another, merge into one another.

In a preferred embodiment, the monitoring means is controlled accordingly to monitor other contours when deflected by the deflection. If, for example, a horizontal security surface with a circle-shaped outer edge folded by a deflecting mirror in a vertical security surface, the circular (segment) shaped outer edge would be folded into a complex curved vertical outer edge. By controlling the monitoring means in accordance with a development or refolding of the desired, for example substantially linear, vertical outer edge, such a desired vertical outer edge can be produced. In general, the edge of a security surface monitored by the monitoring means can be predetermined by retransformation or imaging of the desired edge by the deflection means onto the security surface, which would monitor the monitoring means without upstream deflection means.

According to a preferred embodiment, an operating mode of the manipulator in dependence on a monitored security field is executable. In particular, it can be provided that driving the mobile base is only possible if an at least substantially horizontal safety surface in the direction of travel in front of the base is monitored by the monitoring device. Preferably, the position of a diverter is monitored using secure technology to ensure that the mobile base moves only when an at least substantially horizontal safety surface is being monitored.

If an object is detected in a security area, various reactions of the manipulator can be carried out, in particular depending on the operating mode and / or guarded security area. Thus, for example, the manipulator can be navigated around an obstacle or avoid an obstacle, travel to a safe position, execute an emergency stop, issue a, in particular visual and / or audible warning signal, or the like. Similarly, it is also possible, regardless of the operating mode always perform the same reaction, for example, always an emergency stop.

As explained in the introduction, a security area may consist of several areas, wherein preferably each area is monitored by a monitoring means. In a preferred embodiment, the monitoring means and / or deflection means are controlled differently in an operating mode. For example, a first monitoring means, preferably by upstream of a deflection, monitor a vertical portion, while a second monitoring means, preferably by removing a deflection, monitors a horizontal portion. The total monitored by the monitoring device with the two monitoring means safety surface is then partially vertical, regionally oriented horizontally. By switching one of the two monitoring or deflection means, the safety surface can be oriented completely horizontally or completely vertically.

Further advantages and features emerge from the subclaims and the exemplary embodiments. This shows, partially schematized:

1A a mobile robot according to an embodiment of the present invention from the side in a first mode of operation;

1B : the robot after 1A from above;

2A : the robot after 1 in a second operating mode in 1A corresponding representation;

2 B : the robot after 2A from above;

3A : the robot after 1 in a third operating mode in 1A corresponding representation; and

3B : the robot after 3A from above.

1A shows a mobile robot according to an embodiment of the present invention from the side in a first mode of operation, 1B from above. By way of example, the mobile robot has a multi-axis articulated arm 1 on that on a mobile basis 2 is fixed, which can move by means of wheels in the area.

The base 2 defines an in 1A recognizable rectangular base. At two diametrically opposite corners monitoring means in the form of laser scanners are near the ground 3 arranged, which limit the base area. Each of these two laser scanners monitors in the in 1 illustrated first operating mode, a horizontal circular segment area A and B, the edge of the horizontal pivoting and detection range of the scanner 3 is predetermined. The laser scanners pivot for monitoring 3 their beams horizontally by the laser heads and / or optics are pivoted accordingly.

B bilden. Wird in dieser Sicherheitsfläche ein nicht vorgesehenes Hindernis erkannt, erfolgt eine entsprechende Reaktion. Beispielsweise versucht der Roboter bei ausreichendem Abstand, um das Hindernis herum zu navigieren. Hierzu kann die Basis 2 gegebenenfalls auch angehalten werden oder rückwärts vom Hindernis weg fahren. Zusätzlich oder alternativ kann eine Bewegung des Knickarmes 1 relativ zur Basis 2 entsprechend beschränkt oder gesperrt werden. Reichen diese Maßnahmen nicht aus, um eine Kollision des Armes 1 bzw. der Basis 2 mit dem Hindernis zu verhindern, wird ein Nothalt ausgeführt, um den mobilen Roboter, i. e. Arm 1 und Basis 2 sicher stillzusetzen.Moves the mobile base, so is the mobile robot in the in 1 indicated first operating mode. The two laser scanners 3 Monitor the two horizontal security areas A, B, which together the monitored horizontal security area A.

B form. If an unforeseen obstacle is detected in this safety area, a corresponding reaction takes place. For example, with sufficient clearance, the robot attempts to navigate around the obstacle. This can be the basis 2 if necessary, stop or drive backwards away from the obstacle. Additionally or alternatively, a movement of the articulated arm 1 relative to the base 2 be limited or blocked accordingly. These measures are not enough to make a collision of the arm 1 or the base 2 With the obstacle to prevent, an emergency stop is carried out to the mobile robot, ie arm 1 and base 2 safely shut down.

If the base 2 is free in the environment, ie, there are no environmental components in the circle segment areas A, B, the robot is in a modified first mode of operation. If an unforeseen obstacle is now detected in the still horizontal safety surface, this results from the fact that the obstacle moves towards the stationary robot. Accordingly, here is only a limitation or blocking the movement of the articulated arm 1 relative to the base 2 provided as a reaction. In a modification, it is also possible here to evade using a method of the mobile base 2 be provided.

2 show the mobile robot in 1 corresponding representation in a second operating mode. The robot is in this second mode of operation, if provided that its mobile base 2 in the area stands and his articulated arm 1 does not leave the working space which extends vertically above the base, that is, if, according to a work program or In particular, in an autonomous robot, according to a work task is provided that the articulated arm 1 just above the base of the mobile base 2 surgery. The second mode of operation may also be used instead of that described above with reference to FIG 1 modified modified first operating mode can be selected, in particular, when the mobile robot is not free, but in a close environment.

B' kann dadurch vorgegeben werden, dass die Laserscanner, insbesondere ihr Schwenk- und Erfassungsbereich, entsprechend geändert wird, und/oder, dass die Spiegel 3 entsprechend geformt sind. Allgemein kann die Transformation der Sicherheitsfläche A

B (vgl. 1) in A'

B' (vgl. 2) zum Beispiel dadurch realisiert werden, dass zunächst die Spiegel 3 so gestaltet werden, dass sie die horizontalen Flächen A, B in vertikale Flächen A', B' mit je einer Kante falten, und anschließend die Steuerung der Laserscanner 3, insbesondere die Kontur ihres Erfassungsbereichs, entsprechend angepasst wird. Für diese Anpassung kann beispielsweise die gewünschte Kontur (im Ausführungsbeispiel der 2 im Wesentlichen lineare Grenzen) rechnerisch entsprechend der Abbildungsgesetze der Spiegel 4 auf die Horizontale abgebildet werden, und die Laserscanner 3, die als solche nur die Horizontale überwachen, derart angesteuert werden, dass sie in der Horizontalen Sicherheitsflächen mit diesen abgebildeten Grenzen überwachen.In the second mode of operation are mirrors 4 by means of a pivoting device 5 in front of the laser scanner 3 pivoted. This will be the result of the laser scanners 3 Horizontally emitted beams are deflected vertically and now paint over with a horizontal pivoting of the laser scanner 3 two vertical sections A 'and B', respectively, in one edge (left (top) and right (bottom) in FIG 2A ( 2 B )) and together so wrap the base vertically upwards. The outer, in particular upper, edge of this vertical safety surface A '

B 'can be specified by the fact that the laser scanner, in particular its pan and detection area, is changed accordingly, and / or that the mirror 3 are shaped accordingly. In general, the transformation of the security area A

B (cf. 1 ) in A '

B '(cf. 2 ) be realized, for example, that first the mirror 3 be designed so that they fold the horizontal surfaces A, B in vertical surfaces A ', B', each with an edge, and then the control of the laser scanner 3 , in particular the contour of its detection range, is adjusted accordingly. For this adaptation, for example, the desired contour (in the embodiment of the 2 essentially linear boundaries) arithmetically according to the mapping laws of the mirrors 4 be imaged on the horizontal, and the laser scanner 3 , which as such, only monitor the horizontal, are controlled so that they monitor in the horizontal security areas with these imaged limits.

B in diesem Bereich vertikal entlang der Grundfläche der mobilen Basis orientiert ist.It can be seen in the synopsis of 1 . 2 good that both orientations can also be mixed in another operating mode. For example, if the mobile base is in 1B . 2 B can only move diagonally to the top left, with the articulated arm 1 relative to the base 2 can always extend only in this direction - if necessary, beyond the base area - may be provided that only the in 1 . 2 right mirror 4 before the in 1 . 2 right laser scanner 3 is pivoted, so that the monitored in this operating mode security area of the in 1 shown area B and the in 2 shown area A 'composed. In this way, the robot can safely navigate in the direction of travel. At the same time it is possible to stay close to the in 1B . 2 B right lower corner without triggering a monitoring response, since the monitored security area A '

B is oriented vertically in this area along the base of the mobile base.

B' derart modifiziert ist, dass sich auf der in 3 rechten Seite der Grundfläche kein vertikaler oder horizontaler Sicherheitsflächenbereich erstreckt. Dies kann beispielsweise durch eine entsprechend geänderte Ansteuerung des in 3 rechten Laserscanners 3 und/oder einen entsprechend geformten Spiegel realisiert sein. Insbesondere kann die in 3 rechte Schwenkvorrichtung 5 den Spiegel 4 in zwei Stufen vor den Laserscanner 3 schwenken, wobei in einer ersten Stufe ein Bereich des Spiegels 4 vor dem Laserscanner 3 angeordnet ist, der dessen horizontalen Sicherheitsflächenbereich A in die vertikalen Sicherheitsflächenbereiche A' transformiert, während in der zweiten Stufe ein Bereich des Spiegels 4 vor dem Laserscanner 3 angeordnet ist, der dessen horizontalen Sicherheitsflächenbereich A in den vertikalen Sicherheitsflächenbereich A'' transformiert. Dies kann alternativ auch dadurch realisiert sein, dass im dritten Betriebsmodus Objekte in der in 2B rechten Flanke der Sicherheitsfläche A' nicht registriert bzw. ignoriert werden. 3 show the mobile robot in 1 . 2 corresponding representation in a third mode of operation. The robot is in this third mode of operation, if provided that its mobile base 2 in the area stands and his articulated arm 1 the working space, which extends vertically above the base on the in 3 For example, to leave workpieces from the base in the environment, to pick up workpieces from the environment, or otherwise to contact the environment. Basically, the third corresponds to the second operating mode, but the safety surface A "

B 'is modified so that on the in 3 right side of the base area no vertical or horizontal safety surface area extends. This can be done, for example, by a correspondingly changed control of the in 3 right laser scanner 3 and / or realized a correspondingly shaped mirror. In particular, the in 3 right swivel device 5 the mirror 4 in two stages in front of the laser scanner 3 pivot, wherein in a first stage an area of the mirror 4 in front of the laser scanner 3 is arranged, which transforms the horizontal security surface area A in the vertical security surface areas A ', while in the second stage, an area of the mirror 4 in front of the laser scanner 3 is arranged, which transforms the horizontal security surface area A in the vertical security area area A ''. This can alternatively also be realized by the fact that in the third operating mode objects in the in 2 B right flank of the safety area A 'can not be registered or ignored.

The operating mode that determines the security area to be monitored can be selected, for example, in the form of linked or cascaded queries. Thus, for example, the first operating mode can always be present when the robot is moving. For example, the second mode of operation may be subordinate if the base 2 stands and the arm 1 according to the work program to be executed, does not move beyond the working space vertically above the base of the mobile base 2 extends and so through the laser scanner 3 is limited.

Conversely, the execution of a mode of operation, preferably in secure technique, require that a corresponding safety surface is monitored. For example, in safe technology, it can be monitored that the mirrors 4 from the laser scanners 3 so they can freely monitor a horizontal security area before moving to a mobile base 2 ie the first operating mode is allowed.

This can be realized in a preferred embodiment in that in each case at least one, preferably smaller, region of the mirror 4 not mirrored. In the second and third operating modes, this area is not part of the safety area, for example by the laser scanner 3 this unreflected area is not covered or this area is ignored on detection.

Should now be moved in the first operating mode, as long as a mirror 4 is still folded down, would also be in the first mode of operation, the above-discussed unreflected area of this mirror by the laser scanner 3 sampled and recorded as a (very close) obstacle.

LIST OF REFERENCE NUMBERS

1

articulated

2

mobile base

3

Laser scanner (monitoring means of a monitoring device)

4

Mirror (deflection)

5

swivel mechanism

A, ..., A '', B, B '

Security area

Claims (12)

Method for monitoring a manipulator, in particular a robot, with a mobile base ( 2 ), wherein a monitoring device ( 3 ) in a first operating mode ( 1 ) of the manipulator monitors a first safety surface (A, B), characterized in that this monitoring device is in a second operating mode ( 2 ) of the manipulator one of the first different second security area (A ', B', A '') monitors. A method according to claim 1, characterized in that two security areas (A, A ', A' ', B, B'), which are monitored in different operating modes, at least partially differ in their orientation, contour and / or extent. Method according to claim 2, characterized in that at least one area (A, B) of a security area is oriented at least substantially horizontally and at least one area (A ', A ", B') of another security area is oriented at least substantially vertically; and / or that a safety surface encloses a working space, at least substantially, completely vertically and another safety surface does not completely vertically surround the working space, but has at least one recess. Method according to one of the preceding claims, characterized in that, preferably mechanically, electromagnetically, electromotively, hydraulically and / or pneumatically, optionally a deflection means, in particular a mirror ( 4 ), at least one monitoring means, in particular a laser scanner ( 3 ) is arranged to monitor different security areas. Method according to one of the preceding claims, characterized in that an operating mode of the manipulator in dependence on a monitored security field is executable. Method according to one of the preceding claims, characterized in that the monitoring device in a third operating mode of the manipulator, the first security area, the second security area or a different from the first and second security area third security area (A '

B) monitored. Method according to one of the preceding claims, characterized in that the base of the mobile manipulator moves in an operating mode in an environment and is in a different operating mode relative to the environment. Method according to one of the preceding claims, characterized in that a member ( 1 ), in particular a tool, of the manipulator remains in an operating mode within a limited by monitoring means of the monitoring device working space and exits in another operating mode from this working space. Method according to one of the preceding claims, characterized in that the mobile manipulator is in an operating mode freely in an environment and is limited in another operating mode by the environment. Method according to one of the preceding claims, characterized in that a reaction of the manipulator is carried out if an object is detected in a security area. Method according to one of the preceding claims, characterized in that the monitoring device at least one non-contact, in particular optical, monitoring means, in particular a laser scanner ( 3 ), having. Mobile manipulator, in particular robot, with a monitoring device ( 3 ), characterized in that it is used to carry out a Method according to one of the preceding claims.

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