WO2018145990A1

WO2018145990A1 - Device for securing a machine-controlled handling apparatus and method

Info

Publication number: WO2018145990A1
Application number: PCT/EP2018/052519
Authority: WO
Inventors: Eckhard Wellbrock; Martin Reinhold
Original assignee: Thyssenkrupp System Engineering Gmbh; Thyssenkrupp Ag
Priority date: 2017-02-08
Filing date: 2018-02-01
Publication date: 2018-08-16
Also published as: DE102017202004A1

Abstract

The invention relates to a device (20) for securing a machine-controlled handling apparatus (10), in particular a robot, having a sensor system (22) for sensing objects (10, 12) located in a monitoring space (34) associated with the handling apparatus (10) and having an evaluating unit (24) for determining position data and motion data of the objects (10, 12) located in the monitoring space from sensor signals of the sensor system (22).

Description

Device for securing a machine-controlled handling device and method

The invention relates to a device for securing a machine-controlled handling device, in particular a robot, with sensors for detecting objects located in a monitoring space associated with the handling device and an evaluation unit for determining position data and movement data of the objects located in the monitoring space Sensor signals of the sensors.

The term handling device should be both mechanically controlled, fixed-programmed so-called pick-and-place devices, such as devices for loading, assembly or packaging, as well as universally applicable motion machines - so-called industrial robots - with multiple axes, their movements in terms of motion sequence and the trajectory are freely programmable, be understood.

Nowadays, machine concepts are demanded by the user in which a human-robot collaboration with a conventional industrial robot is implemented. The DIN EN ISO 10218 prescribes a distance and speed monitoring of the operator to protect the operator against hazards that emanate from the industrial robot during operation. In the event that only a permanently installed sensor system is used, it is mandatory to monitor a large monitoring area around the industrial robot. If, for example, so-called floor scanners or running mats are used, they lead to a large minimum distance between the industrial robot and the operator. The reason for this is a detection of the feet or the lower leg of the operator, so that according to DIN EN ISO 13855 a distance of 1.2 m to a prescribed distance for the lower extremities are added in order to take into account the reach of the outstretched arms. However, floor scanners and foot mats have the advantage that they can monitor a large interstitial space without gaps. In contrast, security cameras can not consistently monitor a surveillance space because movement of the industrial robot within the monitored area could result in undesirable emergency stops. Such a sensor is therefore not suitable to reduce the required safety distance between industrial robot and operator while maintaining a safe working environment so far that a direct cooperation between the industrial robot and the operator can be displayed. Such a sensor system is described for example in WO 2006/024431 AI. Another way to significantly reduce the required safety distance between industrial robot and operator while maintaining a safe working environment, consists in a protective sheath created by a sensor directly to an effector of the industrial robot or to the recorded there tool or component. Relative to the entire interstitial space, there is only monitoring in the vicinity. For this purpose, the sensors on the industrial robot must be co-moving, advantageously directly on the robot arm. Thus, EP 2 323 815 B1 discloses a robot arrangement with a contactless distance sensor arranged in or on the end effector, which is a capacitive distance sensor. The robot is a so-called redundant robot that can perform motion in its null space, so can reconfigure its joints while maintaining the position of the effector. With such a sensor, it is not possible to monitor the movement of the industrial robot within a larger surveillance space around the industrial robot, that is in a remote area. Consequently, it is not possible to carry out continuous assembly work in collaboration with an operator with an industrial robot which is equipped with a sensor effective in the near range, since the industrial robot accommodates components stored in a component memory as well as supplies the picked-up component to the immediate mounting location then the operator, for example, performs a screwing of the component. Consequently, both the surveillance space in the remote area, namely for receiving the component and the supply to the installation site, as well as in the vicinity, namely the direct assembly operation by the operator, have to be implemented in order to implement concepts of human-robot collaboration.

Based on this, the object of the present invention is to provide a device for securing a handling device, which provides a suitable combination of sensors, which allows a human-robot collaboration with small working distances.

The object is achieved by a device for securing a mechanically controlled handling device, in particular a robot, comprising a sensor system for detecting objects located in a monitoring device associated with the handling device, an evaluation unit for determining position data and movement data of the objects located in the monitoring space Sensor signals of the sensor, wherein the sensor is designed such that with respect to the interstitial space, a first, monitoring-stationary monitoring area and a second, variable-origin monitoring area can be detected. In this context, an origin-stationary monitoring area is to be understood as meaning that the origin of this area is immovable with respect to the entire apparatus or relative to a higher-order coordinate system. The origin here is the point from which the monitoring is carried out by suitable means. In contrast, an origin variable monitor area is understood to mean that the origin of this area is movable relative to the parent coordinate system. Thus, for example, the case may arise that the originating stationary surveillance area extends over the entire surveillance area, ie coincides with it, and the originally variable surveillance area covers and also moves in a partial area of the surveillance area. It may also be the case that the originating stationary monitoring area extends over a subarea of the entire surveillance space and the originally variable surveillance area covers and also moves in another subarea of the surveillance space.

By means of the device according to the invention, it is possible to implement concepts of human-robot collaboration, since it is advantageously possible to achieve a basic protection of the handling device via the origin-stationary monitoring area and to ensure a well-resolving detection of a working area via the origin-variable monitoring area. Thus, it is particularly preferred that the origin-variable monitoring area is formed as a three-dimensional area. In this case, it is preferred that a three-dimensional and origin-variable monitoring area be placed around an effector of a handling device. This offers the advantage that, in the case of direct cooperation between the handling device, in particular its effector, and the operator, in particular their hands and fingers, a control of the handling device can take place at any time taking into account the proper movements of the operator. In particular, it is provided in this case that the evaluation unit determines position data and movement data of both the handling device and the operator and transfers them either as raw data or as processed data via a suitable interface to a machine control of the handling device. The machine control then imprints the handling device corresponding movements, so that there is no risk of injury to the operator. An advantageous embodiment of the invention accordingly provides that the first monitoring area is a remote area starting from a base of the handling device and the second monitoring area is a short range starting from a movable effector of the handling device. With the combination of long-range and short-range monitoring and thus secure detection of the hands and / or fingers The operator can minimize the necessary safety distance between the machine-controlled handling device and the operator.

An advantageous embodiment of the invention provides that the first monitoring area is aligned close to the ground, in particular forms a plane parallel to a floor level. As a result, the basic security of the handling device is ensured so that it can be reliably detected that an operator is located in the monitoring space around the handling device.

An advantageous embodiment of the invention provides that the evaluation unit is set up to distinguish position data and movement data acquired in the first monitoring area from position data and movement data acquired in the second monitoring area and / or to evaluate them in combination. Preferably, it is further provided that the evaluation unit can distinguish position data and movement data of a first object from position data and movement data of a second object. This makes it possible in an advantageous manner that a control of the handling device can be carried out in dependence on a different detection of the objects. Thus, for example, it is conceivable that initially only a detection takes place in the first monitoring area of both a first object, for example the handling device, and a second object, for example the operator. In the course of a production process, it is then conceivable that a detection in the second monitoring area also takes place of the first object and of a second object. In any case, it is crucial that the evaluation unit can distinguish the two objects from each other.

An advantageous embodiment of the invention provides that the evaluation unit assigns several monitoring levels representing Sensierungsfelder the interstitial space. This makes it possible to store different activation modes depending on the security levels in the evaluation unit. It is thus preferable to assign different traversing speeds to the handling device from the evaluation unit, at least indirectly, to the different security levels, depending on detection of the objects in the sensing fields.

The object is further achieved by a method for securing a mechanically controlled handling device with a device as described, with the following steps:

Detecting a first object guided by the manipulator in a first sensing field of the surveillance space and detecting a second object located in a second sensing field; - Imprinting a first traversing speed at least indirectly via the evaluation unit to the handling device;

- detecting the entering into a third Sensierungsfeld second object;

Impressing a second travel speed, reduced in relation to the first travel speed, at least indirectly via the evaluation unit to the handling device;

Detecting the first object guided by the manipulator into the second and / or third and / or fourth sensing field and detecting the second object entering the third sensing field;

- Imprinting a relation to the second speed reduced third Verfahrge- speed at least indirectly via the evaluation unit on the handling device;

Detecting a movement of the second object in the fourth sensing field;

- stopping the handling device at least indirectly via the evaluation unit.

An advantageous embodiment of the method provides for detecting the first and second objects located in the first, second and third sensing fields via the first, original-state monitoring area.

An advantageous embodiment of the method provides for detecting the first object located in the fourth sensing field via the first, stationary-stationary monitoring area.

An advantageous embodiment of the method provides for detecting the second object entering the fourth sensing field via the second, originally variable monitoring area.

An advantageous embodiment of the method provides for detecting the first object guided by the handling device into the first sensing field and detecting a movement of the second object from the fourth sensing field and impressing the second traversing speed increased compared to the third traversing speed at least indirectly via the evaluation unit the handling device before.

An advantageous embodiment of the method provides for detecting the second object entering into the first sensing field and for impressing the first traversing speed, which is increased relative to the second traversing speed, at least indirectly via the evaluation unit to the handling device.

The invention is explained below with further features, details and advantages with reference to the accompanying figures. The figures illustrate only exemplary embodiments of the invention. Show here Figure 1 is a schematic representation of a handling device with a safeguard device;

2 shows a handling device with a safety device in a first work situation;

FIG. 3 shows a handling device with a safety device in a further work situation;

4 shows a handling device with a safety device in a further working situation and

FIG. 5 shows a flow diagram of a possible method for securing a handling device.

1 shows a schematic representation of a handling device in the form of an industrial robot 10 and an operator 12, which can enter into a collaboration with the industrial robot 10. The industrial robot 10 and the operator 12 are thus installed or present in the same workspace. The industrial robot 10 has an effector 16 at a free end of a robot arm 14, which can be designed, for example, as a tool, gripper, screwdriver, camera or measuring device. The industrial robot may be an articulated robot or a robot with another arm kinematics. Furthermore, a device 20 for securing the handling device is shown, which may include a sensor 22 and an evaluation unit 24. In this case, the sensor system 22 may initially comprise a permanently installed sensor 26 which is fastened, for example, to a frame element 18 of the industrial robot 10. It can also be provided that a plurality of sensors 26 are arranged around the circumference of the frame element 18, so that a sensor element 30 surrounding the frame element 18 and thus the industrial robot 10 can be generated, as will be described later. The sensor 26 may be, for example, a laser sensor, a footswitch mat, a camera or time-of-flight camera or an ultrasound sensor.

The sensor system 22 may further include a sensor 28 disposed on the robot arm 14, which may be referred to as a movable sensor 28 due to the mobility of the robot arm 14. The movable sensor 28 is preferably attached to the free end of the robot arm 14 adjacent to the effector 16. It is expedient if the movable sensor 28 is arranged in a position vertically above the effector 16 and produces a screen-shaped directed sensor field 32 enclosing the effector 16. The sensor field may, for example, be directed substantially downwards, but any other orientation is possible as needed. It is expedient in this case if the movable sensor 16 is arranged such that the generated sensor field 32 is not shaded by the effector 16 or other movable sensor. che parts of the robot arm 14 learns. The sensor 26 may be, for example, a laser sensor, a camera or time-of-flight camera or an ultrasonic sensor.

The industrial robot 10 and the device 20 for its protection can be integrated in a workstation, which is not shown per se, and in which, for example, an assembly process is performed. It can also be provided that the workstation is processually linked via a transport system with one or more other workstations.

Furthermore, FIG. 1 shows a monitoring space 34 around the industrial robot 10. Appropriately, it is provided that the securing device 20 is also disposed within the monitoring space 34. However, it can also be provided that the securing device 20 is arranged at least partially outside the monitoring space 34.

FIGS. 2 to 4 show the industrial robot 10, the securing device 20 and the operator 12 in respective work situations. The sensor field 30 is shown as a horizontally oriented plane. It may be provided that the sensor field is divided to 30 _n in a plurality of concentrically extending to the sensor 26 part 30i circles 30, wherein each part circuit 30i to 30 _n a different security level is assigned. Here, under a security level is understood to be a quantification of light emanating from the industrial robot to the operator hazard potential when the operator resides in one of the runs in the pitch circles sensor arrays 30i to 30 _n. In a practical embodiment, it can be provided that different security speeds are also assigned to different traversing speeds of the industrial robot 10. Thus, it is expedient to reduce the traversing speeds of the industrial robot 10 stepwise from an outer sensor field to an inner sensor field, if an operator is detected in a sensor field.

FIG. 2 shows a situation in which the industrial robot 10 picks up a component via its effector 16 at a buffer space (not shown). Meanwhile, for example, the operator 10 may be in the outermost sensor field 30i, which is assigned the lowest security level with a high travel speed Vi. In the position of the operator, it is spatially impossible for the robot arm 14 to come into contact with the operator 12. The travel speed Vi in this situation is, for example, 1000 mm / s.

FIG. 3 shows a situation in which the industrial robot 10 has moved the component into the area of the sensor fields 30 ₂ to 30 ₄ and at the same time the operator 12 has entered the next inner sensor field 30 ₂ . This sensor field 30 ₂ may be associated with a lower travel speed v ₂ compared to the travel speed Vi. Thus recognizes the evaluation unit 24 via the sensor 22 that an operator 12 has moved from the sensor field 30i into the sensor field 30 ₂ , the evaluation unit 24 impresses the industrial robot 10 or a control unit of the industrial robot 10, not shown, the reduced travel speed v ₂ . The travel speed v ₂ in this situation is, for example, 500 mm / s. FIG. 4 shows a situation, compared to FIG. 3, in which the operator 12 first entered the next inner sensor field 30 ₃ . This sensor field 30 ₃ can be assigned a lower travel speed v ₃ compared to the travel speed v ₂ . If the evaluation unit 24 recognizes the sensor field 30 ₃ , the evaluation unit 24 impresses the industrial robot 10 or a control unit of the industrial robot 10 (not shown) with the reduced travel speed v ₃ . Furthermore, a situation is shown in FIG. 4 in which the operator 12 has extended an arm in the direction of the effector 16 or the component held thereon, thereby entering the sensor field 32 generated by the sensor 28. If the evaluation unit 24 detects via the sensor system 22 that the operator is in the sensor field 32 at least with parts of his body - arms, hands, fingers or other body parts - the evaluation unit 24 sends a hold command to the industrial robot 10 or not shown control unit of the industrial robot 10 so that it stops and remains in a position in which the operator 12 can make, for example, the assembly of the component.

FIG. 5 shows a flow diagram of a possible method for securing a machine-controlled handling device 10.

In summary, the safety device 20 is provided via the evaluation unit 24 with a control option with which the travel speed of the industrial robot 10 can be reduced as soon as the distance to an operator 12 has reduced and with which the travel speed of the industrial robot 10 can be set to zero as soon as possible a defined minimum distance between industrial robot 10 and operator 12 is reached or fallen below. In this case, it is advantageously provided that the sensor field 30 of the permanently installed sensor 26 and the sensor field 32 of the co-moving sensor 28 are switched dynamically depending on the situation. LIST OF REFERENCE NUMBERS

10 industrial robots

12 operator

14 robot arm

16 effector

18 frame element

20 device

22 sensors

24 evaluation unit

26 sensor

28 sensor

30 sensor field

32 sensor field

34 surveillance space

Claims

claims

1. Device (20) for securing a machine-controlled handling device (10), in particular a robot, comprising

a sensor system (22) for detecting objects (10, 12) located in a monitoring space (34) associated with the handling device (10),

an evaluation unit (24) for determining position data and movement data of the objects (10, 12) located in the monitoring space (34) from sensor signals of the sensor system (22),

wherein the sensor system (22) is designed in such a way that, with respect to the monitoring space, a first, monitoring-station-side monitoring area (30) and a second, monitoring-variable monitoring area (32) can be detected.

A device (20) according to claim 1, characterized in that the first monitoring area (30) is a remote area from a base of the manipulator (10) and the second surveillance area (32) is a near area from a mobile one Effector (16) of the handling device (10) acts.

3. Device (20) according to claim 1 or 2, characterized in that the first monitoring area (30) is aligned close to the ground, in particular forms a plane parallel to a floor level.

4. Device (20) according to any one of claims 1 to 3, characterized in that the evaluation unit (24) is adapted to, in the first monitoring area (30) detected position data and movement data of in the second monitoring area (32) detected position data and to differentiate movement data and / or evaluate them in combination.

5. Device (20) according to one of claims 1 to 4, characterized in that the evaluation unit (24) the monitoring space (34) a plurality of different security levels representing Sensierungsfelder (30i ... 30 ₂ , 30 ₅ ) assigns.

6. Device (20) according to claim 5, characterized in that the different security levels are assigned to the handling device (10) of the evaluation unit (24) at least indirectly verfahrgeschwindigkeiten (v _n ), depending on a detection of the objects (10, 12 ) in the sensing fields (30i ... 30 ₂ , 30 ₅ ).

7. A method for securing a mechanically controlled handling device (10) with a device (20) according to any one of claims 1 to 6, comprising the steps:

Detecting a first object (10) guided by the handling device (10) in a first sensing field (30i) of the monitoring space (34) and detecting a second object (12) located in a second sensing field (30 ₂ ) of the monitoring space (34) ;

- Imprinting a first traversing speed (vi) at least indirectly via the evaluation unit (24) on the handling device (10);

Detecting the second object (12) entering a third sensing field (30 ₃ ) of the interstitial space (34);

- Imprinting a relation to the first traversing speed (vi) reduced second traversing speed (v ₂ ) at least indirectly via the evaluation unit (24) on the handling device (10);

Detecting the first object (10) guided by the manipulator (10) into the second and / or third and / or fourth sensing field (30 ₂ , 30 ₃ , 30 ₄ ) of the interstitial space (34) and detecting it in the third sensing field ( 30 ₃ ) entering second object (12);

- Imprinting a relation to the second traversing speed (v ₂ ) reduced third traversing speed (v ₃ ) at least indirectly via the evaluation unit (24) on the handling device (10);

- Detecting a movement of the second object (12) in a fifth Sensierungsfeld (32) of the interstitial space (24);

- stopping the handling device (10) at least indirectly via the evaluation unit (24).

8. The method of claim 7, characterized by detecting the first, second, third and fourth Sensierungsfeld (30i ... 30 ₄ ) located first and second object (10, 12) over the first, stationary stationary monitoring area.

9. Method according to claim 8, characterized by detecting the first object (10) located in the fourth sensing field (30 ₄ ) via the first, stationary-stationary monitoring area.

10. The method according to any one of claims 7 to 9, characterized by detecting the entering into the fifth Sensierungsfeld (32) second object (12) via the second, the origin variable monitoring area.

11. The method according to any one of claims 7 to 10, characterized by the further steps:

- detecting the first object (10) guided by the handling device (10) into the first sensing field (30i) and detecting a movement of the second object (12) out of the fourth sensing field (30 ₄ );

Imprinting the second travel speed (v ₂ ), which is increased relative to the third travel speed (v ₃ ), at least indirectly via the evaluation unit (24) onto the handling device (10).

12. The method as claimed in claim 11, characterized by detecting the second object (12) entering into the first sensing field (30i) and impressing the first traversing speed (vi) increased relative to the second traversing speed (v ₂ ) at least indirectly via the evaluation unit (24) the handling device (10).