EP0656868A1

EP0656868A1 - Process and device for controlling a portainer.

Info

Publication number: EP0656868A1
Application number: EP93919193A
Authority: EP
Inventors: Johann F Hipp
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-08-28
Filing date: 1993-08-26
Publication date: 1995-06-14
Anticipated expiration: 2013-08-26
Also published as: EP0656868B1; DE59305281D1; WO1994005586A1; SG52219A1

Abstract

A process and device are disclosed for controlling a portainer. The positions of points at an edge of the cargo handling gear or of a container received therein, as well as the position of a point at an edge located at a destination site, are measured and converted into signals for controlling the portainer drive.

Description

Device and method for controlling a container crane.

The invention relates to a device and a method for controlling a container crane.

A number of different types of cranes are used for handling containers. This includes common ship unloading cranes that can be moved freely or on rails, as well as gantry cranes or e.g. Jib cranes. What they all have in common is that they have a movable lifting device on which a loading tableware is suspended. The loading gear is designed in such a way that it can grip and hold the common types of containers.

There are a number of different handling situations. The most common situation is that a container is picked up with an empty loading harness and transported to a destination. On the one hand, this destination can be a suitable parking area, e.g. the loading area of a truck or a freight wagon, but on the other hand also be another container that serves as a stacking base.

Correct control of the loading gear between a starting point and a target point is made difficult by the following factors: 1. the loading gear hanging freely on the lifting device behaves like a pendulum and can be set into undesirable vibrations due to the movement of the lifting device or external influences, such as wind,

2. the point at which the loading gear or the container attached to it is to be set down is not always optimally visible and

3. In the event that containers are transshipped from a ship to land or vice versa, flow-related movements of the ship are to be compensated.

In addition, when loading or unloading e.g. Ships that continuously change the load configuration (i.e. the height of the individual stack of containers to be crossed by the loading tackle), which must also be taken into account to avoid collisions.

At the present time, the movement of the loading gear along the transport path is controlled manually under the sight of a crane operator. The crane operator usually works with so-called instructors who e.g. by radio to help set down the empty or loaded loading gear at the destination.

It goes without saying that the crane driver in particular carries out an extremely responsible task which can only be completed by highly qualified personnel. But even in this case there is always the risk of human error, in which the instructors in the vicinity of the destination are particularly endangered and the cargo can also be damaged. Irrespective of this, the personnel expenditure currently required when handling containers is too high. It is therefore an object of the invention to provide a device and a method with which the movement of the loading gear required when handling containers can be at least partially automatically controlled.

The object is achieved by means of a device according to claim 1 and a method according to opening 9.

The device according to the invention works with at least one sensor attached to the crane, which is able to scan surfaces located within the lifting range of the loading gear and to measure at least one point on edges located therein that have a minimum jump in height. The minimum jump in height is specified with regard to the selected edge to be scanned so that the sensor specifically recognizes this edge and applies it to further z. B. adjacent edges do not respond with a lower jump in height.

The distance sensor can be e.g. act as a sensor described below, which scans a line or a surface in a predetermined angular range with resolution decreasing over the distance. The sensor is oriented in such a way that in any case it measures a point on a selected edge, in particular a horizontal edge, of the loading device or a point on a selected edge of the container accommodated in the loading device. When approaching a container that is to be gripped by the loading gear or serves as a stacking base for a container to be unloaded, the sensor also measures a point on a selected edge of this target container. The device is designed in such a way that it generates control signals for the crane drive for steering the loading gear into an engagement position with the target container from the measurement data determined by the sensor on the basis of the known dimensions of the loading gear or containers contained therein.

The device according to the invention in particular enables automatic height control of the empty or loaded loading device. dishes related to a target container. It can be assumed that the destination for the loading gear is often a destination container. However, it is just as well possible that a loaded load is brought up to an empty storage area, for example on a truck or freight wagon. Such shelves generally also have characteristic edges, which can be measured by means of the sensor in at least one point. If the term target container is used in the context of this application, then it always also includes those (container-free) destinations that have at least one edge that can be detected by the sensor and that clearly defines the position of the storage surface.

Within the scope of the invention it is possible to measure edges with any orientation by means of the sensor. It is sensible, however, to select horizontally or essentially horizontally oriented edges for the measurement. With increased computing effort or the use of several sensors, of course, points on inclined, non-horizontal edges can also be measured and related to one another. For example, assume that a truck usually has a slightly beveled shelf with corresponding edges to be measured. Destination configurations of this type can also be detected and calculated with the device according to the invention.

Embodiments of the invention are protected in the subclaims, with which further automation of the loading device control can be achieved.

These configurations can in particular be implemented in cranes which can be moved overall parallel to one of the horizontal edges of the target container and whose lifting device (trolley) can be moved transversely thereto parallel to a further upper horizontal edge of the target container. In the case of a ship crane, the crane can be moved on wheels or rails, for example, parallel to the longitudinal edges of target containers stacked in transverse rows on a ship. The lifting device is in the direction of the transverse rows movable with loading gear aligned parallel to the target containers. This type of crane is described in detail only because it is commonly used for handling larger quantities of containers and because of the given spatial dimensions in which the crane and lifting device move, sensor-controlled automation makes it particularly simple. Irrespective of this, however, any other crane, for example a gantry or slewing crane, can of course also be equipped with the device according to the invention. In the case of such cranes, only a greater amount of processing work has to be carried out when converting the determined measurement data into control signals. In principle, however, sensor-controlled automation of the loading harness movement is also easily possible here.

The problem has already been mentioned above that the empty or loaded loading gear hanging on the lifting device behaves like a dynamic system. Already due to the movement of the lifting device, but also as a result of e.g. Wind can cause undesired vibrations. Theoretically, the extent of this oscillation can already be measured by measuring a point e.g. determine a selected edge of the loading gear or the container accommodated therein, provided that the selected edge to be scanned is and remains oriented transversely to the plane of vibration. The expected pendulum motion cannot, of course, always be predicted. Especially with pendulum movements, which are overlaid by a rotation of the hanging load, e.g. when moving a container with mass distribution, the measurement of a single edge point can no longer be sufficient to determine the degree of a possible deflection.

An advantageous embodiment according to claim 2 therefore provides that two points located on parallel edges of the load harness or a container accommodated therein are measured by means of the sensor. In the case of continuous measurement, the measured values obtained in each case (which allow a specific statement about the deflection and angular position of the loading gear) the vibration movement can be determined. The device then automatically generates signals that control the crane drive to dampen the vibration.

It is conceivable that the two parallel edges are scanned with a sensor. Corresponding sensors with suitable viewing angles are available. However, the resolution of such sensors decreases as the viewing angle increases, which is why an embodiment according to claim 3 is preferred which assigns each edge to be scanned a separate sensor of higher resolution. If these sensors, as proposed in claim 4, are arranged in different axial positions with respect to the edges to be scanned, then measured values are obtained from which the angular position and deflection of the loading gear can be determined with relatively little computation effort.

In particular, the last-mentioned device also permits a particularly simple parallel alignment of the empty or loaded loading gear to a target container. If, as suggested in claim 5, the sensors are furthermore arranged in a somewhat laterally arranged manner (so that they can look under the loading equipment or a container accommodated therein), then the empty or loaded loading equipment can be moved automatically into one position in which it is located above the target container and aligned parallel to it. The empty or loaded loading gear only has to be adjusted in the direction of the container longitudinal axis for a "flush" engagement position.

With the device according to the invention in the embodiments described so far, for example, the longitudinal edges of a loading gear can be automatically aligned with the longitudinal edges of a target container. This means that the crane operator is relieved of several difficult control processes. For a flush lowering of the load, for example, on a target container, it is additionally necessary that an alignment with respect to the transverse edges is also carried out. This alignment can be done manually by the crane operator, for example. In addition to the example the sensors scanning the longitudinal edges may be provided with further sensors which measure points on the transverse edges.

Advantageously, however, in a configuration according to claim 6, a sensor is provided which is movably received on the crane in the direction of the edge to be scanned. Such a sensor can be moved along the edge to be scanned and its (or its) end points measured. Knowing at least one end point of an edge of the target container to be scanned, the exact position thereof can be determined and the crane can be moved accordingly. In this embodiment, in the simplest case, the alignment of the empty or loaded loading gear to the longitudinal and transverse edges can be done in the simplest case control the destination container. As a rule, it is sufficient to carry out this measurement process once per row of container transshipment. However, should the containers e.g. loaded onto or lifted from a ship, then it makes sense to determine the end points of the edges of the target container (or containers located in the same transverse row) to be scanned at regular intervals and, if necessary, to move the ship due to current etc. to compensate for the corresponding method of the crane. Of course, it is furthermore also possible to simultaneously determine the end points of the edges of the loading gear to be scanned and of a container possibly accommodated therein, as well as the edge of the target container to be scanned.

The sensor is advantageously attached directly to the lifting device. In this way, an optimal overview of the transport process by means of the sensor is made possible.

The sensor can be designed as a 2D distance image sensor. Such a sensor generates a measuring beam swiveling in one plane with constant determination of the outside angle and the beam travel time. Beam travel time is the time it takes, for example, a light pulse after emitting to reach an object after reflection on an object to be measured. catcher to return. The distance of an object to the sensor can be calculated via the beam travel time. A common example for such a distance measurement is, for example, the radar measurement. Using the data determined by the 2D distance image sensor (angle, beam travel time), the spatial coordinates of a measured point can be defined in relation to the sensor. A laser beam or a microwave beam can serve as the measuring beam, for example.

If the scanning plane of the 2 D distance image sensors described above is additionally pivoted, then an area scan is obtained which, for example, Can provide information about the positions of points on a longitudinal and a transverse edge of the target container. Such a sensor (3D distance image sensor) supplies all three coordinates to the measured points.

As already mentioned above, the measurement data determined by the sensors are converted into control signals in the device according to the invention. The computing processes required for this are part of the basic technical knowledge, as is their computer-controlled implementation in control signals for a crane drive. However, it should also be pointed out that, in particular in the case of the embodiment in which the sensor is movably arranged on the crane, its respective position with respect to the crane is also recorded and included in the location calculations. This ensures that the necessary control signals can be generated regardless of the position of the sensor on the crane.

The invention is not limited to a device for controlling container cranes. Rather, a corresponding method is also to be protected.

In this regard, reference is made to independent claim 9. Advantageous refinements of the method are protected in subclaims 10 and 11. The principle of the method according to the invention is to measure at least one point in each case of a selected upper, in particular horizontal, edge of the loading gear, a container possibly accommodated therein and, when approaching a destination, at least one point of a selected edge of this destination. Knowing the measured values, the height position and also the side position of the edges with respect to one another can be determined and, from the known dimensions of the loading gear and any container possibly accommodated therein, the difference in height and side to the destination (the configuration of which is also known) ) into the crane computer or into another computing unit that controls the crane drive. At this point, too, it should be pointed out again that a destination can be represented both by a target container to be gripped or used as a stack base, but also by a storage space for containers, for example on a ship, freight wagon or truck. It is only essential for the method according to the invention that there is a avoidable edge in the destination area which is clearly geometrically related to the destination configuration. In the event that the destination is a container, this can be, for example, one of the upper horizontal edges of the container.

In embodiments of the method according to the invention, it is provided that further points of further edges of the loading gear, a container accommodated therein and, if appropriate, the destination are measured. In this way, the loading gear can be aligned with the destination not only with respect to its lifting height, but also with respect to further geometric axes.

In order to avoid repetitions, reference is made to the relevant explanations regarding the device claims.

The main areas of application of the method according to the invention (and also of the device) discussed so far relate to the approximation and alignment of the loading gear and any container contained therein to a destination and the automatic 1Ü matic damping of any vibrations of the loading gear. In the following, a further embodiment of the method according to the invention is to be dealt with, which relates in particular to the transport route of the loading harness between the destinations. As already explained above, containers are placed next to one another, in particular on ships in transverse rows, and further containers are stacked on top of these containers. The lifting device is moved over the row of (to be dismantled) containers. In the course of the transhipment, the height of the individual stack of containers in the row changes (depending on the loading plan). Care must be taken that the loading harness is guided in a safe distance on its transport route over the upper containers in the row. Due to the constantly changing configuration of the row of container stacks to be set up or dismantled, manual control of the transport route requires a high degree of concentration. According to claim 10 it is therefore provided that at least one upper horizontal edge of each container crossed by the loading gear is measured in at least one point. For this purpose, the same sensor can be used that is also used to measure points on the load harness, a container possibly contained therein and the target container. The sensor is expediently attached to the lifting device and oriented essentially vertically looking downwards.

On the basis of the measured values, a surface profile of the load configuration can be determined with a computing unit, for example in the crane computer, which can be taken into account when controlling the loading gear via the stack of containers to be set up or dismantled. The data entered into the computer are updated with each movement of the loading gear, whereby changes in the loading configuration during the handling, but also in the unloading or loading of the ship, for example, due to a change in the ship position caused by the tidal range are taken into account. The invention is to be explained in more detail below with the aid of several representations which relate to exemplary embodiments.

Fig. 1 shows schematically a container crane with a

Embodiment of the device according to the invention is equipped.

2 shows another crane,

3 shows the approach of a transported container to a destination container using a schematic drawing.

In Fig. 1, a container crane 10 is shown when handling containers 12 stacked in a transverse row 11. The container crane 10 has a bridge 14 which can be moved on wheels 13 and on which a lifting device 15 which can be moved in the longitudinal direction of the bridge is accommodated. On the lifting device 15 there is suspended a loading device 16 with which the containers 12 can be gripped and held. The lifting gear 16 can be moved by the lifting device 15 into any vertical position below the bridge 14.

So far, the container crane 10 shown in FIG. 1 corresponds to the prior art. According to the invention, however, a number of sensors 17a, b, 18a, b are now arranged on the lifting device 15. The sensors 17a, b are arranged in such a way that, as shown, points 170a, b of longitudinal edges 160a, b of the loading harness 16 are offset in the longitudinal direction, and points 170a ', b' of horizontal longitudinal edges 120a, b are also offset from one another Measure containers 120. As explained later in FIG. 3, the height difference between the loading harness 16 and the surface of the container 120 can in particular be easily calculated from the respectively determined point measurement values and a parallel alignment of the longitudinal axes of the loading harness 16 to the longitudinal axis of the container 120 can also be checked . If, as in the given case, the bridge 14 already leads to the container row 11 is aligned. By means of the measurement data determined by the sensors 17a, b, the loading harness 16 can be automatically and easily controlled in a loading operation with one of the containers 12, for example the container 120.

However, the alignment of the bridge 14 to the row of containers 11 can also be automated. The sensors 18a, b serve for this purpose, of which the sensor 18a sweeps a line parallel to the container row 11 with its viewing area 180a (the viewing area of the sensor 18b was not shown for reasons of clarity). To align the crane 10, it can e.g. are moved so far in the longitudinal direction of the container 12 until the viewing area 180a of the sensor 18a detects the end edge corner points of the container 12. The position of the row of containers 11 relative to the crane 10 can be clearly established on the basis of these measured values. It is then sufficient to move the crane 10 until the load harness 16 is arranged centrally over the row 11.

This alignment of the crane can, however, also take place by means of the sensors 17a, b. For this purpose, the crane 10 must be moved in one direction until e.g. the sensor 17a reaches the closer end of the upper horizontal edge 120a of the container 120 which it scans. From the known relationship of the loading harness 16 to the crane 10 and the measured value, the position of the row 11 with respect to the crane 10 can then be determined unambiguously and aligned accordingly. Another possibility described above would be to assign the sensor (s) 17a, b to be movable in the direction of the scanned edge 120a, b in the lifting device 15. In this case, it would be sufficient to move the sensor 17a (and not the entire crane 10) accordingly in order to determine the corner point of the scanned edge of the container 120.

FIG. 2 shows a container crane 20 which in principle corresponds to the crane 10 shown in FIG. 1. Here, too, a bridge 22 which is movable on wheels 21 is provided, on which a lifting device 23 is accommodated so as to be movable in the longitudinal direction of the bridge 22. The Associated with lifting device 23 and movable with it, a driver's cab 50 is provided on bridge 22. A crane driver can control the loading activities from the driver's cab 50. A vertically movable loading gear 24 is suspended from the lifting device 23 and is currently in loading engagement with a container 25. The container 25 belongs to a whole series of further containers, also designated by the reference numeral 25, which are arranged in a transverse row 26 in stacks 27 arranged side by side. In the case shown, the container 25 gripped by the loading gear 24 is to be reloaded onto a truck 28.

To control the loading process, sensors 29a and 29b are provided on the lifting device 23, the sensor areas 290b, 290a of which each measure a point of the upper horizontal longitudinal edges of the loading gear 24.

With the help of the sensors 29a, 29b, the empty loading gear 24 was first lowered onto the container 25 in a targeted manner (shown state). Now the loading gear 24 loaded with the container 25 is moved to the truck 28, with the sensors 29a, 29b additionally sweeping over the surfaces of the container stack 27 and in each case measuring a point on the longitudinal edges of the containers 25 delimiting the surfaces becomes. On the basis of the measured values, a profile of the surfaces defined by the container stack is created in the crane computer, which can be updated with each loading movement of the loading gear 24 or the lifting device 23. The crane computer can thus automatically provide a collision-free route to the desired destination for each container transport, in this case the truck 28.

The truck in turn has upper horizontal edges 30, 31 which can be measured by the sensors 29a, 29b in at least one point. On the basis of the measured values determined for the truck, the container 25 gripped by the loading tackle 24 can be lowered precisely onto the loading area of the truck 28. 3 roughly schematically shows a typical handling situation in which a container 40 is to be placed flush on a target container 41. All other components of the crane transporting the container 40 have been omitted for reasons of clarity. The reference symbols 42 and 43 denote points which were measured by means of a sensor 60 fastened to the crane (not shown) on one of the upper longitudinal edges of the container 40 and the container 41. For the measurement, a measuring beam 600 is pivoted by the sensor 60 over an angular range 61 in one plane. The beam travel time is determined at a defined beam angle. From the beam travel time, the distance between the sensor and a point reflecting the beam can be determined from the outside angle of the beam, its angular position to the sensor. In this way, coordinates can be calculated for each point measured by the sensor, which indicate the vertical and horizontal position of the point in relation to the sensor. In the present case, points 42 and 43 were measured on the upper horizontal longitudinal edges of the containers 40 and 41 by means of the measuring beam 600 in the angular positions A ^ and A2. The vertical distance Δ h and the horizontal distance Δ X between points 42 and 43 can be determined from the corresponding coordinates.

For precise placement, the container 40 and with it the measuring point 42 must be moved so far that the value Δ X goes to zero and the value Δ h becomes equal to the known height of the container 40 Δ C. Knowing the continuously determined and checked position of the measured values 42 and 43, the corresponding control signals for the crane drive can be generated without problems.

On the basis of the previous description of the sensor 60, it is also clear that a minimum height of an edge to be scanned can easily be specified. For this it is sufficient to relate the individual distance values of the measuring beams 600 emitted by the sensor in different angular positions. For example, if the angle changes slightly, a larger one occurs If the distance changes, there is an edge jump. The relationship between the change in angle and the determined distance values can be set as desired, so that the edge jump triggering a measurement can be adapted exactly to the selected edge to be scanned. In this way it can be ensured, for example, that the sensor reliably detects an outer horizontal edge of the container and does not respond to, for example, smaller edges of stiffening profiles on the container. One could, for example, pretend that the sensor only responds to edges that have a jump at the level of the side wall of the container. As stated above, however, there is absolute freedom of choice here.

Claims

PATENT CLAIMS:

1. Device for controlling a container crane, which has a movable lifting device for a hanging load, with which containers can be gripped and held, characterized in that at least one on the crane (10, 20,) above the load (16, 24) Arranged and looking downward sensor (17a, b; 18a, b; 29a, b; 60) is provided, which is able to scan surfaces located within the lifting range of the loading gear (16, 24) and on edges located therein (160a, b; 120a, b), which have a minimum height jump, to measure at least one point (170a, b; 170a ', b';42; 43) of the edge (160a, b; 120a, b), and the like It is aligned that its scanning area points (170a, b) at least one edge (160a, b) of the loading device (16, 24) or at least one upper edge of a container (25) accommodated in the loading device (24) and when approaching to a target contai to be gripped or used as a stack base ner (120) sweeps over at least one upper edge (120a, b) of the target container (120), the device being determined from the positions of the edge points (170a, b; 170a ', b';42; 43) and from the known dimensions of the loading harness (16, 24) or the container (12, 120, 25, 40, 41) control signals for the crane drive for steering the loading harness (16, 24) or a container attached to it in an engagement position with the target container (120).

2. Device according to claim 1, characterized in that the sensor sweeps over at least two selected parallel edges of the loading gear, or the container accommodated therein.

3. Device according to claims 1 or 2, characterized ge indicates that at least two sensors (17a, b; 29a, b) are provided, the respective opposite parallel edges (160a, b) of the charging harness (16) or one in the Scan the loading tackle of the container.

4. Device according to claims 3 or 4, characterized ge indicates that the two sensors (17a, b) in the direction of the edges to be scanned (160a, b) are offset from one another.

5. Device according to one of claims 1 to 4, characterized ge indicates that the sensor (29a, b) outside the perpendicular projection of a container (25) accommodated in the loading gear (24) is arranged on the crane.

6. Device according to one of the preceding claims, da¬ characterized in that the sensor is movably received in the direction of the scanned selected edge.

7. Device according to one of the preceding claims, da¬ characterized in that the sensor (17a, b; 18a, b; 29a, b) on the lifting device (15, 23) is received.

8. Device according to one of the preceding claims, da¬ characterized in that the sensors (17a, b; 18a, b; 29a, b; 60) are conventional 2 D range finders that generate a beam (600) pivoting in one plane with constant simultaneous determination of the beam angle and the beam travel time.

9. A method for controlling a container crane, in which a loading gear for containers hanging on a movable lifting device for containers in the empty or loaded state is moved back and forth between two changing target locations, the target locations essentially being gripped by one or target container serving as a stacking base or a storage area with a characteristic configuration are characterized, characterized in that by means of at least one sensor (17a, b; 18a, b; 29a, b; 60) arranged on the crane (10, 20) at least one point (170a, b; 170a ', b'; 42) of a selected upper edge (160a, b) of the load harness (16) and / or a container (40) accommodated therein and when approaching the destination (120, 28, 41) a point (170a ¹ , b ': 43) of a selected edge (120, 28) located in the destination (120, 28) can be measured, from the measurement results and the known dimensions of the loading gear ( 16, 24) and one possibly contained containers (40) and the known destination configuration, the height difference and the side difference between the loading gear (16, 24) and the destination (120, 28, 41) are determined and converted into control signals for the crane drive.

10. The method according to claim 9, characterized in that the sensor with respect to or together with the crane in the direction of the selected horizontal edge of the destination and at least one of the two corner points of the selected edge is measured and the crane then accordingly of the measured value determined is moved parallel to the scanned edge in such a way that its loading gear can be moved to the destination without further displacement in the direction of the scanned edge.

11. The method according to any one of claims 8 or 9, characterized ge indicates that by means of the sensor in each case at least one point each of a horizontal edge of all surfaces located on the way between the starting and the destination. Chen measured and a profile of the surface traversed by the loading gear is calculated and supplemented from the measured values. _