Method of moving a load usinsg a crane

Abstract

The present invention relates to a method of moving a load using a crane comprising the steps: defining an origin coordinate system in the crane; defining at least one obstacle coordinate system that is fixedly linked to a deployment location of the load movement; establishing a relationship of the at least one obstacle coordinate system with the origin coordinate system; predefining a travel path of the hook block, preferably with the suspended load, with the aid of the at least one obstacle coordinate system; and converting the travel path from the obstacle coordinate system into actuator controls of the crane for a corresponding movement of the hook block, preferably with the suspended load.

Claims

1. A method of moving a load using a crane comprising the steps: defining an origin coordinate system in the crane; defining at least one obstacle coordinate system that is fixedly linked at least at times to a deployment location of a load movement; establishing a reference of the at least one obstacle coordinate system with the origin coordinate system; predefining a travel path of a hook block with aid of the at least one obstacle coordinate system; and converting the travel path from the obstacle coordinate system into actuator controls of the crane for a corresponding movement of the hook block.

2. The method in accordance with claim 1, further comprising the step: detecting a position and an orientation of the load to be moved in the obstacle coordinate system.

3. The method in accordance with claim 1, wherein the actuator controls for moving the load comprise an individual or common actuation of a lulling movement, of a hoisting movement, of a rotational movement of a superstructure of the crane and/or a telescopic movement of a crane boom.

4. The method in accordance with claim 1, wherein, if the travel path to be converted is implementable by means of a plurality of actuator controls, final actuator controls are reached on a basis of specifications that comprise a maximum payload, a maximum speed and/or a minimal energy consumption.

5. The method in accordance with claim 1, wherein the origin coordinate system is furthermore fixedly linked to the crane; and wherein a spatial relationship of the origin coordinate system and the obstacle coordinate system is made known to a crane control, with the origin coordinate system being at a center of a slewing ring of the crane.

6. The method in accordance with claim 5, wherein a hook block coordinate system is furthermore defined that is fixedly linked to the hook block of the crane, with a movement and a rotation of the hook block coordinate system being reverse calculated to an origin coordinate system fixedly linked to the crane.

7. The method in accordance with claim 6, wherein a camera is used at a boom head to detect the obstacle coordinate system in the crane control; and wherein the hook block coordinate system is aligned superposed with respect to the obstacle coordinate system to make known the obstacle coordinate system in the crane control of the crane.

8. The method in accordance with claim 7, wherein characteristic features of the deployment location, including a building edge or a special topical or construction feature at the deployment location, are used to align the hook block coordinate system at the obstacle coordinate system.

9. The method in accordance with claim 7, wherein an origin of the hook block coordinate system is used to detect the obstacle coordinate system in the crane control in order to make an origin of the obstacle coordinate system and additionally a point of an axis on the obstacle coordinate system known to the crane control of the crane with it.

10. The method in accordance with claim 5, wherein radio GPS transmitters are used to detect the obstacle coordinate system in the crane control that, in interaction with a radio GPS receiver present at the crane, permit the crane control of the crane to draw a conclusion on an orientation and location of the obstacle coordinate system.

11. The method in accordance with claim 1, wherein the crane is arranged in the obstacle coordinate system before the specification of the travel path of the load; and wherein a payload calculation of the crane furthermore takes place for a desired travel path after the specification of the travel path.

12. The method in accordance with claim 6, wherein a tandem hoist of two cranes is provided for the movement of the load; and the origin coordinate systems of both cranes are transmitted into a common obstacle coordinate system.

13. The method in accordance with claim 12, wherein both cranes are coupled to one another before a traveling of the load via a data link that is used to transmit coordinates of the hook block of the one crane in the obstacle coordinate system to the other crane.

14. The method in accordance with claim 13, wherein the other crane moves a position of its hook block in dependence on the coordinates in the obstacle coordinate system of the hook block of the first crane and in dependence on the desired orientation of the load.

15. An apparatus comprising: a crane for moving a load; a crane control for controlling actuators of the crane; and a coordinate system detection device for detecting and fixing a position and orientation of the crane in a spatially fixed obstacle coordinate system that is fixedly linked to a deployment location of the crane; wherein the crane control is configured to travel a load on a basis of the detected position and orientation of the crane in the obstacle coordinate system.

16. The apparatus in accordance with claim 15, wherein the crane control is configured to carry out a payload calculation for a load detected in the obstacle coordinate system after the detection and fixing of the position and orientation of the crane in the spatially fixed obstacle coordinate system.

Description

[0030] Further advantages, features, and details of the present invention will become clear with reference to the following description of the Figures. There are shown:

[0031] FIG. 1: a schematic representation for a straight-line traveling of a load;

[0032] FIG. 2: a schematic representation of the plurality of coordinate systems at a crane;

[0033] FIG. 3: a schematic representation of a travel profile in tandem operation;

[0034] FIGS. 4(a)-4(c): a first possibility of defining an obstacle coordinate system in crane operation;

[0035] FIG. 5: a further possibility of defining the obstacle coordinate system;

[0036] FIG. 6: a third possibility of defining the obstacle coordinate system;

[0037] FIGS. 7(a)-7(b): a fourth possibility of defining an obstacle coordinate system;

[0038] FIGS. 8(a)-8(c): visualized planning steps for moving a load;

[0039] FIGS. 9(a)-9(c): a visualized arrangement for hoisting a load;

[0040] FIGS. 10(a)-(d): visualizations for the individual steps for hoisting a load in an obstacle coordinate system; and

[0041] FIGS. 11(a)-(c): a schematic representation of traveling a load in a tandem hoist in accordance with the present invention.

[0042] FIG. 1 shows a schematic representation or a straight-line traveling of a load along an edge of an obstacle. The crane operator here fixes the direction shown by an arrow and optionally the speed of the movement. The control then calculates how the individual axes and actuators of the crane are to be controlled so that the straight-line movement of the lifting hook or of the load is carried out. It is clear to the skilled person that other, non-straight line travel paths can also be traveled automatically such as circles or free-drawn lines. If the control is to find a plurality of solutions for implementing the travel path since, for example, the travel path can be achieved with the aid of a luffing movement or alternatively thereto by a telescopic movement, such an ambiguity can be resolved using different predefinable specifications. For instance, the maximum payload during the travel movement, a maximum travel speed, or a minimal energy consumption can inter alia be used to resolve such an ambiguity.

[0043] The origin coordinate system of the crane is furthermore also shown in FIG. 1 in which the longitudinal axis of the crane corresponds to the Y axis of this coordinate system. The origin of the coordinate system is typically on the axis of rotation of the superstructure of the crane.

[0044] The conversion carried out in the crane control, that carries out a straight-line movement in the obstacle coordinate system in corresponding controls of the axes and actuators of the crane, typically makes use of the means of coordinate transformation and also of coordinate system transformation.

[0045] FIG. 2 is a schematic representation that shows the plurality of coordinate systems at the crane or in its environment. The spatially fixed obstacle coordinate system 120 whose topographical or construction properties result in frequently demanding load movements is typically present at a deployment location of a crane, that is, at a construction site or the like.

[0046] There is furthermore also the crane-side origin coordinate system whose origin is as a rule at the slewing ring center. The hook block coordinate system 130 that is movable in accordance with the orientation and alignment of the hook block can be recognized as the third coordinate system shown in FIG. 2. It must furthermore be pointed out that the movement and the rotation of the hook block coordinate system 130 to the origin coordinate system 100 using the sensor system and the geometry of the components, which are both known to the crane control, can be calculated by the crane control. The crane control is therefore aware of the spatial relationship of the hook block coordinate system 130 with the origin coordinate system 100 at all times of operation.

[0047] The integration of the obstacle coordinate system is more problematic for the crane control here since the origin of this coordinate system changes its orientation and its location depending on the positioning of the crane at the deployment site. A positioning of the crane at the construction site planned in advance will always differ from the later actual implementation. An attempt could admittedly be made to position the crane at a previously measured point; however, this frequently fails due to the restricted maneuverability of the crane and due to other spatial constraints on a construction site. In addition, such an exact specification of the crane position is extremely laborious and would take up a lot of time.

[0048] It is therefore necessary to make the obstacle coordinate system 120 known to the crane control at the actual crane deployment location after the positioning of the crane so that the origin coordinate system can be brought into a spatial relationship with the obstacle coordinate system 120. The obstacle coordinate system 120 here must be redefined in the crane control (or the orientation and position of the obstacle coordinate system must be made known to the crane control) when the position of the crane (or of the origin coordinate system) changes.

[0049] The use of the obstacle coordinate system 120 is in particular of advantage when a travel movement is desired that is to take place along a straight line.

[0050] If all the coordinate systems are known in the crane control, such as shown with reference to FIG. 2, the hook block can be very simply traveled in the obstacle coordinate system by a distance of 12 m in the Y direction (of the obstacle coordinate system) and can subsequently be traveled by a distance of +5 m in the X direction (of the obstacle coordinate system). The hook block is here traveled by the different crane drives relative to its current position by the above-indicated distances in the obstacle coordinate system. It is clear to the skilled person that this is also possible in three-dimensional space when the Z axis required for this is added to the X axis and the Y axis.

[0051] Alternatively to this, it is also possible to indicate absolute points in the obstacle coordinate system that should be worked through by a travel movement of the hook block. It would thus be possible, for example, to define two spatial points that are arranged at the tips of the two movement arrows starting from the hook block to reach the desired travel destination.

[0052] FIG. 3 is a schematic representation of a tandem operation that provides for a plurality of crane hoists using at least two cranes. It is also of advantage here if the two cranes can make use of one and the same obstacle coordinate system. The control of the plurality of cranes can then be carried out very simply by an operator in the obstacle coordinate system without said operator having to be aware of the respective orientation of the crane to be controlled. Demanding travel paths are possible in tandem operation with the aid of the invention and require a very much smaller lead time. The error-prone simultaneous control by two crane operators during a tandem hoist is also no longer necessary.

[0053] FIGS. 4(a) to (c) represent a possibility of defining the obstacle coordinate system in crane operation. A camera is arranged at the boom head here that looks downwardly in the direction of the ground starting from the boom head. The location and the orientation of the hook block, or of the hook block coordinate system respectively, that is fixedly associated with the hook block, can be recognized by a transmission of this image of the camera to the crane control. The hook block coordinate system or the hook block itself can be positioned at the deployment location via the crane control such that a characteristic feature of the crane deployment location that is associated with the obstacle coordinate system and serves as the origin of the obstacle coordinate system are arranged congruently above one another or are brought into superposition, with the position of the hook block then being communicated to the crane control.

[0054] FIG. 4(c) shows by the thick arrow the path to be covered or covered by the hook block to map the obstacle coordinate system arranged at the edge of the obstacle as congruently as possible with the hook block coordinate system and to thus calibrate it in the origin coordinate system. The known block coordinate system is here duplicated in the camera image shown on the screen. This duplicate is suitably rotated and moved by means of user inputs such as via button operation. Once it is at the correct position (namely at the corner of the obstacle shown at which the obstacle coordinate system is already graphically shown), it becomes the obstacle coordinate system by a repeat user input. The crane control is then aware of the obstacles (buildings, special topographical features or the like) via the construction plan or via an operation schedule. As a result, it thereby becomes possible to input a possible travel path via the touchscreen of a crane control as a free curve in that the travel path is drawn in the crane image by a finger. In the Figures shown, a travel path drawn in this manner only relates to the preset installation height of the crane since the camera cannot itself detect the height. This could, however, be provided with the aid of an altitude sensor, for example.

[0055] The integration of the crane or of the origin coordinate system in the obstacle coordinate system here takes place via the reverse calculation of that position of the hook block at which the hook block coordinate system has been brought into superposition with the obstacle coordinate system with respect to position and orientation.

[0056] FIG. 5 shows a second possibility for making the obstacle coordinate system known to the crane control. For this purpose, travel again takes place with the origin of the hook block coordinate system to the origin of the obstacle coordinate system, with the orientations of the two coordinate systems not having to correspond with one another this time. This state is communicated to the crane control and a point on the X axis of the obstacle coordinate system is selected in a subsequent second step, with this likewise being communicated to the crane control. In a 3D system, the same is also done in a further step for a point of the Y axis of the obstacle coordinate system so that the crane control can calculate the correct orientation and the correct location of the obstacle coordinate system from it.

[0057] A third possibility for making the obstacle coordinate system known is shown in FIG. 6. At least one GPS transmitter 200 having radio transmission to the crane is used here that is at least partially active at predefined points at the construction site. The crane itself likewise has at least one GPS receiver that is configured to receive the signals of the GPS transmitters that are arranged at the obstacle. It is hereby possible to draw a conclusion on the obstacle coordinate system 120. It is clear to the skilled person that all global positioning systems are suitable for this purpose and not just GPS.

[0058] A compass in a portable radio remote control for the crane can likewise be used to make the orientation of the obstacle coordinate system and the origin coordinate system known to the crane control. This is shown by way of example with reference to FIGS. 7(a) and (b). In this respect, the compass installed in the radio remote control is used in interaction with a compass 302 likewise present in the crane to determine the rotation of the crane and the remote control with respect to geographic north. This can be done, for example, in that the remote control is held with a reference surface 301 that is planar against a desired edge 315 at the obstacle (or is aligned in parallel therewith). The angle of rotation is subsequently saved by means of a button so that the rotation between the rotation relative to the crane and the stored rotational angle with respect to geographic north can be calculated using the rotations of the two.

[0059] It is thus achieved that travel can take place relatively in X or Y of the stored position by means of the master switch. It can, however, not be traveled absolutely here since no information on the movement of the two coordinate systems is known. The obstacle coordinate system is accordingly also not present with location and orientation in the crane control.

[0060] The case is also covered by the invention according to which a plurality of the above-shown possibilities for defining or making known the obstacle coordinate system are used.

[0061] FIGS. 8(a) to (c) show the procedure for traveling a load in the planning phase. An obstacle coordinate system is defined in an operation schedule that can run on a PC or also in the crane control (cf. FIG. 8(a)). The frame shown should here represent a display of the operation schedule program.

[0062] For this purpose, the obstacle coordinate system should be aligned at a point of the crane deployment location that is as obvious as possible so that in a later procedure, when the crane is actually on the construction site, the origin of the obstacle coordinate system can be relatively easily brought into superposition with the aid of the hook block. In the present case, there is a rectangle obstacle in which an edge should serve as the origin of the obstacle coordinate system. The longer of the two rectangle edges is here equal to the Y axis, the shorter of them is equal to the Y axis. The calibration later is accordingly facilitated by the use of the striking position on the construction site. A building corner or a building edge is particularly suitable here.

[0063] The position of the load with respect to the obstacle can then furthermore be defined in the operation schedule program.

[0064] FIG. 8(b) shows the positioning of a crane in the operation schedule program.

[0065] Following this step, the travel path of the crane and further intermediate points (attaching the load, rotating the load, etc.) are then defined, with this being able to take place with the aid of a touchscreen or of another input means. It is now possible to carry out a payload calculation in the operation schedule on the basis of the information thus provided. This naturally depends on the type of crane used.

[0066] Unlike FIGS. 8(a) to (c), FIGS. 9(a) to (c) now show the actual position of the crane on a construction site. It can be recognized that it differs from the planned position in the operation schedule program, but this does not bring about any problems on the use of the invention. FIG. 9(b) shows the calibration of the obstacle coordinate system using one of the previously described possibilities. The crane control is thereby now aware of where the crane is to be arranged in the construction site plan that is fixedly linked to the obstacle coordinate system. Since the load is also indicated in the obstacle coordinate system, a repeat payload calculation can now take place whose result can naturally differ from the payload calculation carried out in the planning phase.

[0067] Once the payload calculation has been concluded with a positive result, the crane operator automatically travels the hook block to the starting point of the movement of the load. In so doing, he only regulates the speed with the aid of the master switch and checks that no unexpected collisions with obstacles occur. Once the hook block has arrived above the load to be moved, the load is attached. The crane operator then selects the travel path and specifies the speed by means of his control. The selected paths are then semi-automatically or fully automatically traveled through at the predefined speed (cf. FIG. 9(c)).

[0068] FIGS. 10(a) to (d) and 11)(a) to (c) show the traveling of a load on a predefined load path in a tandem hoist.

[0069] First, the construction site environment is again shown in an operation schedule program, cf. FIGS. 10 (a) to (d). The frame shown should here represent a display of the operation schedule program. The position and the orientation of a load should furthermore be defined by means of a coordinate system (cf. 10 (a)). An obstacle that is to be traveled around is furthermore also located on the construction site. It is therefore suitable to define an obstacle coordinate system, with again a striking point on the construction site being used to facilitate the calibration of the obstacle coordinate system in the crane control. In a similar manner as with a hoist using only one crane, the travel path of the load and possibly required intermediate points (attachment of the load, rotation of the load, etc.) also have to be defined in the subsequent planning step for the tandem hoist. This can be simply carried out by moving the load in the program.

[0070] FIG. 11(a) now shows the arrangement of the two cranes in the planning tool; the frame again stands for the representation in the operation schedule program. The lashing points of the load are defined here and assigned to a respective crane. The cranes are in the further procedure also defined so that the payload can be observed. A separate travel profile thus results for each crane to hold the load in the desired orientation and in the desired position at every point of the travel path.

[0071] It must be taken into account here that the travel paths are dependent on one another since the other crane has to adopt a specific position at each point of the one crane. It is of advantage for the calculation and for the entering of the travel path for the two travel paths of the cranes to relate to the obstacle coordinate system.

[0072] FIG. 11(b) and FIG. 11(c) now no longer show the planning tool, but rather the actual arrangement of the two cranes on a construction site. This does not have to take place exactly as provided in the planning tool.

[0073] Both cranes are now each separately calibrated for the obstacle coordinate system, with reference again being made to the methods provided further above for this purpose. A repeat payload calculation can then take place for the planned travel path of the respective crane. If the payload calculation does not produce any difficulties, both cranes move over the load into a position that enables a connection of the load to the respective cranes. Subsequently, the two cranes have to be coupled to one another so that they have a reliable data link to one another. One of the crane operators then takes over the speed control, with provision preferably being able to be made that the other crane operator has to release the load movement. This can be done, for example, with the aid of a button, the so-called dead man's switch. If the so-called dead man's switch is released by the second crane operator, both cranes stop.

[0074] Since the crane has different crane drives, that drive of a crane component that can carry out the movement the slowest determines the maximum speed to carry out the movement sequence.

[0075] The traveling of the load then takes place such that the first operator increases the speed and his crane starts to move. The crane in so doing transmits the X-Y coordinates of its position of the hook block in the obstacle coordinate system to the other crane. The other crane thereupon changes the position of its hook block using a corresponding regulation so that the desired orientation of the load and the desired movement of the load are achieved. The load is thus traveled as previously defined in master-slave operation. Both cranes stop automatically on too great a difference.

[0076] It is possible to carry out a particularly demanding tandem hoist reliably and precisely using the present invention.