MONITORING DEVICE AND METHOD FOR PROTECTING HAZARDOUS AREAS

Description

[0001] The invention relates to a monitoring device and a method for securing hazardous areas.

[0002] Known monitoring devices are used to monitor hazardous areas on vehicles, which can be designed in particular as driverless transport systems or generally as autonomous, i.e., self-driving vehicles. Typically, a sensor is arranged on the front as part of the monitoring device. This sensor monitors the area in front of the vehicle as a hazardous area in order to rule out collisions. A particularly suitable sensor for this purpose is an optical sensor in the form of an area distance sensor, i.e., a scanning distance sensor.

[0003] Such an area distance sensor performs object detection within a protective field adapted to the danger zone. If the area distance sensor detects an object in the protective field, it generates a safety signal that is transmitted to the vehicle's control system, stopping the vehicle and thus preventing dangerous collisions.

[0004] US 2019 / 105 788 A1 relates to a safety system for safeguarding the cooperative operation of humans, robots, and machines in a technical installation. The safety system comprises a first safety-related device configured to monitor a first danger zone of the technical installation and to transfer the technical installation to a safe state when a dangerous situation is detected. The safety system is further configured to identify an autonomously operating technical unit and to register the autonomously operating technical unit when it fulfills a defined condition, as well as to restrict the monitoring of the first danger zone by the first safety-related device in response to the registration.

[0005] WO 2017 / 067876 A1 relates to a method for operating a manipulator system, comprising in particular an automated guided vehicle and further in particular an automated guided vehicle, wherein a protective field of the manipulator system is monitored by a monitoring device. According to the method, environmental information concerning an environment of the manipulator system is provided, the protective field is adapted based on the environmental information, and the adapted protective field is monitored by the monitoring device.

[0006] The invention is based on the object of providing a monitoring device and a method by means of which a location-flexible and safe monitoring of danger areas is possible.

[0007] To achieve this object, the features of the independent claims are provided. Advantageous embodiments and expedient developments of the invention are described in the dependent claims.

[0008] The invention relates to a monitoring device having a vehicle on which a vehicle control system and at least one sensor are present. The sensor is designed to detect objects within at least one protective field. A contactless communication device is provided which is designed for data transmission between the sensor and / or the vehicle control system on the one hand and a machine control system of a stationary machine. Using the sensor alone, hazardous area monitoring can be carried out in different areas of the machine, wherein a hazardous area on the machine is monitored by positioning the vehicle relative to the machine such that the hazardous area is at least partially enclosed by the protective field. A safety signal is generated in the machine control system depending on sensor signals from the sensor.

[0009] The invention further relates to a method for securing danger areas.

[0010] The basic idea of ​​the invention is therefore to use a sensor provided on a vehicle, which is designed for protective field monitoring, for danger area monitoring on stationary machines, whereby the term machine also includes complex systems.

[0011] This enables flexible, comprehensive danger zone monitoring on machines of various types.

[0012] In industrial applications, systems and machines typically perform complex, time-varying functions, which means that depending on the operating location and process step of the machine, different hazard areas can arise both locally and over time.

[0013] Such hazardous areas must generally be secured by appropriate protective measures to avoid danger to people.

[0014] Permanently installed protective devices, such as safety fences, can be used for this purpose. Apart from the fact that these protective devices require considerable installation effort, they also block the area surrounding the respective machine, making it particularly difficult to transport materials to or from the machine. Another disadvantage is that such protective fences do not allow for adaptation to changing operating conditions of the machine and the resulting different danger zones.

[0015] Similar difficulties also arise with sensors permanently installed on the machine for monitoring hazardous areas. These can only monitor changing hazardous areas to a limited extent.

[0016] Particularly in machines or production plants with numerous hazard points that change location or time due to process-related factors, the continuous monitoring of each individual hazard point with permanently installed protective devices involves significant material and installation costs. This means that all machine areas are constantly monitored, even though, due to process-related factors, only a subset of these areas poses a hazard at any given time.

[0017] These problems are solved in a surprisingly simple manner with the monitoring device according to the invention.

[0018] According to the invention, a sensor arranged on a vehicle and thus mobile is used for danger area monitoring on a stationary machine.

[0019] The sensor or vehicle control unit is connected to the machine control unit via a communication device, allowing them to exchange data. Using this communication device, the sensor on the vehicle can be used for hazardous area monitoring on the stationary machine.

[0020] For this purpose, the vehicle is positioned, preferably automatically, on the machine in such a way that the protective field at least partially, and particularly advantageously completely, encompasses the hazardous area to be protected. The hazardous area on the stationary machine is then detected by the sensor in such a way that any intrusion of objects into the protective field is monitored. The corresponding sensor signals are then sent directly from the sensor or from the vehicle control system via the communication device to the machine control system, where they are used to generate a safety signal. The machine control system then advantageously generates a shutdown command if the optical sensor detects an object intrusion into the protective field.

[0021] Since the vehicle is a mobile unit that can be flexibly positioned at different locations, hazardous area monitoring can be performed at different parts of the machine using just the vehicle's sensor. Furthermore, the vehicle can, of course, be positioned at different machines, allowing hazardous area monitoring to be performed at multiple machines using the vehicle's sensor.

[0022] In order to meet the normative requirements for use in the field of safety technology, particularly in the field of personal protection, the vehicle control system, the machine control system, the sensor and the communication device form safety-related units.

[0023] For this purpose, the machine control system, the vehicle control system, and the sensor can have a fail-safe, particularly redundant, dual-channel design. The communication device can ensure fail-safe data transmission by safeguarding with checksums or the like. The communication device can, for example, be designed to transmit radio signals bidirectionally.

[0024] Advantageously, the sensor is an optical sensor or a radar sensor, which is designed to detect objects within two- and / or three-dimensional protective fields.

[0025] The sensor is preferably a distance sensor.

[0026] In particular, the optical sensor is an area distance sensor or a camera sensor.

[0027] In principle, the optical sensor can also be formed by a series arrangement of light sensors that form a reflective light curtain.

[0028] According to an advantageous embodiment, the vehicle is an autonomous vehicle.

[0029] It is particularly advantageous for the machine control system to send a target position at which the vehicle is to be positioned to the vehicle control system via the communication device.

[0030] Based on the transmitted target position, the vehicle control system can then move the vehicle to this target position, so that no further adjustment processes are required.

[0031] It is also advantageous for the current actual position of the vehicle to be transmitted from the vehicle control system to the machine control system via the communication device at predetermined time intervals.

[0032] This allows for a time-based coordination of the times at which hazardous area monitoring on the machine can be carried out using the vehicle's sensor.

[0033] The actual position can be determined using a lane guidance system on the roadway, which is scanned by suitable sensors. The lane guidance system can be implemented in the form of 2D barcodes, RFID tags, or similar devices. Alternatively, the actual position can be determined by detecting known stationary objects.

[0034] Furthermore, the vehicle control system can also exchange data with the machine control systems of multiple machines. This allows for scheduling when the vehicle control system's sensor is used to monitor a hazardous area on a specific machine. Suitable positioning can preferably be specified for this purpose, particularly through suitable requests sent from the machine control system to the vehicle control system via the communication device.

[0035] According to a particularly advantageous development of the invention, a danger zone on the vehicle can be monitored by means of the sensor.

[0036] This further enhances the functionality of the monitoring device according to the invention. Hazardous area monitoring can be performed, particularly during vehicle travel, using the sensor on the vehicle itself, especially in front of it. Hazardous area monitoring can be performed on a machine during vehicle downtimes.

[0037] The functionality of the monitoring device according to the invention can be further increased by navigating the vehicle based on sensor signals from the sensor.

[0038] Further flexibility in the monitoring carried out with the sensor is achieved by the fact that the sensor can be used to monitor objects in different protective fields.

[0039] For this purpose, a specific protective field can be activated from a large number of protective fields, particularly in the sensor.

[0040] This allows a suitable protective field to be selected in the sensor depending on the situation, enabling optimal adaptation to the respective danger area to be monitored.

[0041] According to an advantageous embodiment, an adjustment device is provided on the vehicle by means of which the orientation of the sensor can be adjusted.

[0042] Depending on the orientation of the optical sensor, a protective field can be activated.

[0043] This adjustment option allows the orientation of the sensor's protective field to be adapted to the specific hazardous area situation. For example, if the sensor is used as an area distance sensor, a camera sensor, or a retro-reflective light curtain to monitor a flat, two-dimensional protective field, the sensor's adjustment direction can be adjusted to monitor a protective field oriented in a horizontal or vertical plane.

[0044] In addition to the monitoring sensors, an IP camera can also be installed at an adjustment point or at another location on a vehicle, especially an autonomous vehicle, to visualize and capture live images of the monitored protective field. Live stream images from the camera can then be transmitted to a production control center for visual monitoring via the vehicle's wireless communication system.

[0045] The invention is explained below with reference to the drawings. They show: Figure 1: Schematic representation of the monitoring device according to the invention. Figure 2: Embodiment of a sensor for the monitoring device according to Figure 1 Figure 3: First application example for monitoring with the monitoring device according to Figure 1 . Figure 4:Second application example for monitoring with the monitoring device according to Figure 1 .

[0046] Figure 1 shows an embodiment of the monitoring device 1 according to the invention. On an autonomous vehicle, which in this case is designed as a driverless transport system 2, four sensors 3 are arranged as components of the monitoring device 1. In this case, these sensors are designed as optical sensors 3. In principle, the sensors 3 could also be designed as radar sensors.

[0047] The sensors 3 are identical in this case, but this is not mandatory. Figure 1 shows, a sensor 3 is arranged at each corner of the driverless transport system 2. However, the arrangement and number of sensors 3 can also be based on the configuration according to Figure 1 be different. In this case, the sensors 3 are pivotally mounted on adjustment devices 4.

[0048] A navigation sensor 5 is arranged on the front of the driverless transport system 2. The navigation sensor 5, as well as the sensors 3, are connected to a vehicle control system 6. The navigation sensor 5 generates navigation signals that are read into the vehicle control system 6 for navigation of the driverless transport system 2. The navigation sensor 5 can, for example, detect lane guidance on the roadway on which the vehicle is moving, thereby allowing the current actual position to be determined. The lane guidance can be formed by a linear arrangement of 2D barcodes or RFID tags, which encode absolute position values ​​that are recorded by the navigation sensor 5.

[0049] In general, sensors 3 can also be used for navigation purposes. An additional navigation sensor 5 is not required in this case.

[0050] Figure 1further shows a stationary machine 7, which is controlled by a machine controller 8, which is a component of the monitoring device 1 according to the invention. A communication device 9 is provided as a further component of the monitoring device 1 according to the invention. The communication device 9 comprises a first communication module 9a, which is connected to the vehicle controller 6, and a second communication module 9b, which is connected to the machine controller 8. Bidirectional data transmission takes place via the communication modules 9a, 9b. In the present case, the data is transmitted in the form of radio signals. For this purpose, a radio transmitter and a radio receiver are provided in each communication module 9a, 9b.

[0051] The monitoring device 1 is used in the field of safety technology. For this purpose, its components, in particular the vehicle control system 6, the machine control system 8, the communication device 9, and the sensors 3, are designed as safety-related units. The vehicle control system 6 and the machine control system 8 can consist of two cyclically monitoring computer units. Data transmission via the communication device 9 can be verified by checksums.

[0052] The optical sensors 3 of the monitoring device 1 are designed as area distance sensors in the present case. A corresponding embodiment is shown in Figure 2. The area distance sensor shown there in its side view has a transmitter 11 emitting light beams 10 and a receiver 12 receiving light beams 10, which form a distance sensor operating according to a pulse-time of flight method. To determine the distance of an object 13, the flight time of the light beams 10 from the transmitter 11 to the object 13 and back to the receiver 12 is determined in an evaluation unit 14 and converted into a distance value. The transmitter 11 and receiver 12 are arranged in a rotating measuring head 15. This sits on a stationary base 16 in which the evaluation unit 14 is housed. The motor-driven measuring head 15 rotates about a vertical axis of rotation (relative to the illustration according to Figure 1These sensor components are arranged in a housing 17 mounted on the base 16. The light beams 10 are guided through a window 18 in the housing 17. A switching output 19 for signal output is connected to the evaluation unit 14.

[0053] The rotational movement of the measuring head 15 periodically deflects the light beams 10 within a scanning area located in a horizontal plane. The angular range of the scanning area is determined by the extent of the window 18 in the circumferential direction of the housing 17.

[0054] By continuously measuring distances and determining the current angular positions of the light beams 10, the position of objects 13 in the scanning area can be determined.

[0055] For use in the field of safety technology, the evaluation unit 14 has a redundant structure in the form of two cyclically monitoring computer units.

[0056] In general, the sensors 3 can also be designed as camera sensors or reflex light curtains.

[0057] Sensors 3 generally monitor the protective field. For example, while the automated guided vehicle system 2 is traveling, two sensors 3 monitor a protective field 20 in front of the automated guided vehicle system 2. The evaluation is preferably performed in the respective optical sensor 3 in such a way that a binary switching signal is generated depending on whether an object 13 is detected in the protective field 10 or not. This means that the switching states of the switching signal indicate whether an object 13 is located in the protective field 10 or not.

[0058] Since the area distance sensors scan a flat scanning area, the protective fields 20, as sub-areas of the scanning area, are also flat areas. If a sensor 3 is designed as a camera or radar sensor, three-dimensional protective fields 20 can also be defined.

[0059] In each sensor 3, several protective fields 20 are stored or several protective fields 20 can be entered into it, so that depending on the requirements in the sensor 3 at least one protective field 20 can be activated, within which object detections are then carried out.

[0060] According to the invention, the sensors 3 of the driverless transport system 2 are also used for monitoring danger areas on machines 7, which in Figure 3 is illustrated. Figure 3 shows a series arrangement of three machines 7, 7', 7", each of these machines 7, 7', 7" having a machine control 8 and a communication module 9b.

[0061] The driverless transport system 2 is positioned on a machine 7 in order to be able to monitor a danger zone of this machine 7. With the sensors 3, partial protective fields can then be monitored, which are located in the Figure 3The protective field 20' shown here is dimensioned so that the entire danger zone on machine 7 is monitored.

[0062] To position the driverless transport system 2, the machine controller 8 of the machine 7 sends a target position to the vehicle controller 6 of the driverless transport system 2. Conversely, the vehicle controller 6 sends the actual position of the driverless transport system 2 to the machines 7 at regular intervals. Using this information, the driverless transport system 2 independently moves to the target position on the machine 7 and takes over danger area monitoring using object controllers in the protective field 20'. If an object intrusion is detected in the protective field 20', a corresponding switching signal is generated in one of the sensors 3 and transmitted to the machine controller 8 via the communication device 9. The machine controller 8 then generates a safety signal which causes the machine 7 to be switched off.

[0063] Depending on the operating mode of machine 7, the size and location of the hazardous area can vary. The protective field 20' can be adjusted accordingly. Furthermore, the automated guided vehicle system 2 can also be moved to the other machines 7 to perform hazardous area monitoring there.

[0064] Figure 4 shows a danger area monitoring in the form of a multi-sided access guard on machine 7 of the machine series arrangement according to Figure 3 .

[0065] The danger area monitoring is carried out with the sensors 3 of two driverless transport systems 2 in the positions designated A and B, while another driverless transport system 2 delivers material to the machine 7.

[0066] A horizontal protective field 20a is monitored by one of the sensors 3 of the automated guided vehicle systems 2 in positions A and B. These protective fields 20a cover the danger zone in front of the machine 7. One sensor 3 of the automated guided vehicle systems 2 in positions A and B is pivoted with the adjustment device 4 so that a vertical protective field 20c is monitored as the boundary of the danger zone with these sensors 3.

[0067] Finally, a protective field 20b is monitored by one sensor 3 each of the automated guided vehicle systems 2 in positions A and B. The protective fields 20b complement each other to form a muting zone. If the automated guided vehicle system 2 in position C is detected as a permissible object 13 within the muting zone, the other sensors 3 monitoring the protective fields 20a are muted so that they do not generate a switching signal that leads to the shutdown of the machine 7. The automated guided vehicle system 2 can then approach the machine 7 from position C and approach material without generating a switching signal that would lead to the shutdown of the machine 7. However, the penetration of an impermissible object 13, a safety-critical object 13 that deviates from the permissible object 13, into the protective fields 20 leads to the generation of a switching signal that causes the machine 7 to be shut down. List of reference symbols

[0068] (1)Monitoring device (2)Automatic guided vehicle system (3)Sensor (4)Adjustment device (5)Navigation sensor (6)Vehicle control (7)Machine (7')Machine (7")Machine (8)Machine control (9)Communication device (9a)Communication module (9b)Communication module (10)Light beam (11)Transmitter (12)Receiver (13)Object (14)Evaluation unit (15)Measuring head (16)Base (17)Housing (18)Window (19)Switching arrangement (20)Protective field (20')Protective field

Claims

1. Monitoring device (1) with a vehicle on which a vehicle control (6) and at least one sensor (3) are provided, wherein the sensor (3) is designed to detect objects (13) within at least one protective field, characterised in that a contactless communication device (9) is provided, which is designed for data transmission between the sensor (3) and / or the vehicle control (6) on the one hand and a machine control (8) of a stationary machine (7) on the other hand, in that a hazardous area monitoring system can be carried out solely with the sensor (3) at different areas of the machine (7) can be carried out, wherein a hazardous area on the machine is monitored by the vehicle being positioned on the machine (7) such that the hazardous area is at least partially enclosed by the protective field, wherein a safety signal is generated in the machine control (8) depending on sensor signals from the sensor (3).

2. Monitoring device (1) according to claim 1, characterised in that the vehicle control (6), the machine control (8), the sensor (3) and the communication device (9) form safety-related units.

3. Monitoring device (1) according to one of claims 1 or 2, characterised in that the sensor (3) is an optical sensor (3) or a radar sensor which is designed to detect objects (13) within two- and / or three-dimensional protective fields.

4. Monitoring device (1) according to one of claims 1 to 3, characterised in that the sensor (3) is a distance sensor.

5. Monitoring device (1) according to one of claims 3 or 4, characterised in that the optical sensor (3) is a surface distance sensor or a camera-sensor.

6. Monitoring device (1) according to one of claims 1 to 5, characterised in that the machine control (8) sends a target position to which the vehicle is to be positioned to the vehicle control (6) via the communication device (9).

7. Monitoring device (1) according to one of claims 1 to 6, characterised in that the vehicle control (6) transmits the current actual position of the vehicle to the machine control (8) at predetermined intervals via the communication device (9).

8. Monitoring device (1) according to one of claims 1 to 7, characterised in that the vehicle is an autonomous vehicle.

9. Monitoring device (1) according to one of claims 1 to 8, characterised in that a hazardous area on the vehicle can be monitored by means of the sensor (3).

10. Monitoring device (1) according to one of claims 1 to 9, characterised in that the vehicle is navigated on the basis of sensor signals from the sensor (3).

11. Monitoring device (1) according to one of claims 1-10, characterised in that object monitoring can be carried out in different protective fields using the sensor (3).

12. Monitoring device (1) according to claim 11, characterised in that a specific protective field can be activated in the sensor (3) from a plurality of protective fields.

13. Monitoring device (1) according to one of claims 1-12, characterised in that an adjustment device (4) is provided on the vehicle, by means of which the orientation of the sensor (3) can be adjusted.

14. Monitoring device (1) according to claim 13, characterised in that a protective field can be activated depending on the orientation of the optical sensor (3).

15. Method for securing hazardous areas by means of a monitoring device (1) with a vehicle on which a vehicle control (6) and at least one sensor (3) are present, wherein the sensor (3) is designed to detect objects (13) within at least one protective field, characterised in that a contactless communication device (9) is provided, which is designed for data transmission between the sensor (3) and / or the vehicle control (6) on the one hand and a machine control (8) of a stationary machine (7) on the other hand, in that a hazardous area on the machine (7) is monitored by the fact that hazardous area monitoring can be carried out solely with the sensor (3) at different areas of the machine (7), wherein the vehicle is positioned on the machine (7) such that the hazardous area is at least partially enclosed by the protective field, wherein a safety signal is generated in the machine control (8) depending on sensor signals from the sensor (3).