Method and system for avoiding collisions in cranes

Abstract

In a method for preventing a collision of a load of a crane with an obstacle, a height profile of the obstacle is captured along a trajectory of movement of the load by at least two sensors for distance measurement. Signals of the sensors are transmitted via at least two communication channels to a controller having at least two operating systems. At least one of the operating systems has a safety program in a secure area. The obstacle is identified along the trajectory via the height profile. The controller includes a secure communications interface for transmitting signals from the controller to a crane control.

Claims

1. A method for avoiding a collision of a load of a crane with an obstacle, comprising: acquiring a height profile of the obstacle along a trajectory of movement of the load by a plurality sensors for distance measurement; sending signals of the sensors via at least two communication channels to a controller with at least two operating systems, of which at least one of the at least two operating systems runs a safety program in a secure region of the controller; and identifying the obstacle along the trajectory on the basis of the height profile, sending a secure stop signal to a crane control by the safety program via a secure communication interface, when the obstacle is acquired within a first clearance from the load in a direction of movement of the load.

2. The method of claim 1, further comprising storing the height profile in the secure region.

3. The method of claim 1, further comprising adapting a size of the first clearance to a speed of the load.

4. The method of claim 1, further comprising sending a secure brake signal to a crane control by the safety program when the obstacle is acquired within a second clearance from the load in a direction of movement of the load.

5. The method of claim 4, further comprising adapting a size of the second clearance to a speed of the load.

6. The method of claim 1, further comprising adapting the trajectory to the height profile.

7. The method of claim 1, further comprising: acquiring a position of the load by at least one of the sensors; comparing the position of the load with a known position; and checking, when the position of the load differs from the known position, a functionality of the at least one of the sensors for distance measurement and/or of a measuring system, with which the known position has been determined.

8. The method of claim 1, further comprising determining a range of visibility by at least one of the sensors.

9. The method of claim 1, wherein at least two computing units are used as controller.

10. The method of claim 1, further comprising: measuring distances along lines which intersect at at least one point of intersection by least two of the sensors; and using the measured values at the at least one point of intersection for validating a secure measured value.

11. A system for avoiding a collision of a load of a crane with an obstacle, comprising: a plurality of sensors for distance measurement, said sensors being configured to acquire a height profile along a trajectory of movement of the load; a controller including at least two operating systems, of which at least one of the operating systems runs a safety program in a secure region of the controller; at least two communication channels for transmitting signals of the sensors to the controller; a secure communication interface configured to transmit signals from the controller to a crane control, a secure stop signal configured to be sent to the crane control by the safety program via the secure communication interface, when the obstacle is acquired within a first clearance from the load in a direction of movement of the load.

12. The system of claim 11, wherein at least one of the sensors is configured as a 2D laser scanner.

13. The system of claim 11, wherein at least one of the sensors is configured as a 3D laser scanner.

14. The system of claim 11, wherein two of the sensors measure distances along lines which form at least one right angle.

15. The system of claim 11, wherein at least one sensor is configured as a multibeam laser.

16. The system of claim 11, wherein at least one of the operating systems is real-time-capable.

17. The system of claim 11, wherein at least one of the sensors is configured for arrangement on a trolley of the crane.

18. The system of claim 11, wherein at least one of the sensors is configured for arrangement on a container spreader of the crane.

19. The system of claim 11, wherein the controller comprises at least two computing units.

20. The system of claim 11, wherein at least two of the sensors measure distances along lines which intersect at least one point of intersection, and wherein the measured values of the at least one point of intersection are used for validating a secure measured value.

21. A crane, comprising a system for avoiding a collision of a load of a crane with an obstacle, said system comprising a plurality of sensors for distance measurement, said sensors being configured to acquire a height profile along a trajectory of movement of the load, a controller including at least two operating systems, of which at least one of the operating systems runs a safety program in a secure region of the controller, at least two communication channels for transmitting signals of the sensors to the controller, a secure communication interface configured to transmit signals from the controller to a crane control, and a secure stop signal configured to be sent to the crane control by the safety program via the secure communication interface, when the obstacle is acquired within a first clearance from the load in a direction of movement of the load.

22. A computer program embodied in a non-transitory computer-readable medium, wherein the computer program, when loaded into a controller and executed by the controller, causes the controller to perform a method for avoiding a collision of a load of a crane with an obstacle, comprising: acquiring a height profile of the obstacle along a trajectory of movement of the load by a plurality of sensors for distance measurement; sending signals of the sensors via at least two communication channels to a controller with at least two operating systems, of which at least one of the at least two operating systems runs a safety program in a secure region of the controller; identifying the obstacle along the trajectory on the basis of the height profile; and sending a secure stop signal to a crane control by the safety program via a secure communication interface, when the obstacle is acquired within a first clearance from the load in a direction of movement of the load.

23. A non-transitory computer-readable medium, having stored thereon a computer program with instructions that, when executed by a controller, causes the controller to perform a method for avoiding a collision of a load of a crane with an obstacle, comprising: acquiring a height profile of the obstacle along a trajectory of movement of the load by a plurality of sensors for distance measurement; sending signals of the sensors via at least two communication channels to a controller with at least two operating systems, of which at least one of the at least two operating systems runs a safety program in a secure region of the controller; identifying the obstacle along the trajectory on the basis of the height profile; and sending a secure stop signal to a crane control by the safety program via a secure communication interface, when the obstacle is acquired within a first clearance from the load in a direction of movement of the load.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention is described and explained in more detail below on the basis of the exemplary embodiments shown in the figures, in which:

(2) FIG. 1 shows a schematic representation of a crane,

(3) FIG. 2 shows a controller according to the invention,

(4) FIG. 3 shows an arrangement of two sensors on a bridge crane,

(5) FIG. 4 shows a representation of safety clearances of the load.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(6) FIG. 1 shows a schematic representation of a crane 2, which is designed as a portal crane in the figure (e.g. as an RTG, “Rubber Tired Gantry”). A load 1, in the image a container, is fastened to a container spreader 15, which is able to travel from left to right in the image by means of a trolley 14. The load 1 is intended to be moved along a trajectory 4, wherein a height profile 6 (“container mountain”) at least along the trajectory 4 is determined by at least two sensors for distance measurement 5. Located along the trajectory 4 is an obstacle 3, meaning that the load is not able to be transported to its destination along a direct path (shown as a dashed line). By way of the method according to the invention, the trajectory 4 is adapted to a parabolic movement which safely clears the obstacle 3.

(7) FIG. 2 shows a representation of the at least two sensors for distance measurement 5, which are connected to a controller 8 via a communication channel 7 in each case. The controller 8 has at least two operating systems 9, 10, of which at least one 10 has a safety program in a secure region. The operating systems 9, 10 are advantageously real-time-capable operating systems 9, 10. The communication with a crane control, in particular for sending a secure stop and/or brake signal, takes place via a secure communication interface 13, which e.g. can be designed as a secure bus (such as PROFISAFE) or as a two-channel hardware interface.

(8) FIG. 3 shows a perspective representation of a crane 2 as in FIG. 1, in which a load 1 is able to travel on a spreader 15 via a trolley 14. In this case, the sensors 5 are arranged on the trolley 14, wherein at least 2D laser scanners are chosen as sensors 5. In this context, one of the sensors 5 records a height profile 6 past one side of the load 1, while a second of the sensors 5 acquires distances while being offset by 90 degrees in relation to the first sensor in the direction of movement of the trolley 14. Here, this second laser scanner additionally acquires the position of the load 1 via the trolley position and the spreader height.

(9) FIG. 4 shows a representation of safety clearances 11, 12, within which an obstacle 3 triggers a secure brake signal if an obstacle 3 is acquired within the second clearance 12, and a secure stop signal is triggered if an obstacle 3 is acquired within the first clearance 11. A monitoring of said safety regions emerging from the safety clearances 11, 12 is possible in this context in a simple manner for example using an arrangement of sensors 5 as has been shown in the preceding FIG. 3.

(10) In summary, the invention relates to a method and a system for avoiding a collision of a load of a crane with an obstacle, and also to a crane with a system of this kind, to a program for carrying out a method of this kind and to a computer-readable medium with a program of this kind. In order to specify a solution for collision avoidance, which fulfills a level of safety, a solution is proposed in which the load is moved along a trajectory, wherein a height profile is acquired at least along the trajectory by means of at least two sensors for distance measurement, wherein signals of the sensors are sent via at least two communication channels to a controller with at least two operating systems, of which at least one has a safety program in a secure region, wherein an obstacle along the trajectory is identified on the basis of the height profile. Furthermore, the controller has a secure communication interface for transmitting signals from the controller to a crane control.