Device for monitoring cargo to be loaded

Abstract

Device (22) for monitoring a cargo (12) to be loaded, in particular one or more containers (14), comprising: at least one sensor (24) designed to detect at least one set of spatial coordinates of measuring points (28), wherein the measuring points (28) are located in a spatial area comprising the cargo (12), an evaluation unit (32) which is designed to: to determine at least part of a contour of the cargo (12) from the set of spatial coordinates of the measuring points (28) and to carry out a comparison between the determined contour of the cargo (12) and at least one predetermined contour, and an output unit (34) configured to output a signal based on a result of the comparison.

Description

The invention relates to a device for monitoring a cargo to be loaded, in particular one or more containers, according to the preamble of claim 1.In loading cargo in harbors, the treatment of containers plays a central role. For moving a container, i.e. for receiving, transporting and re-depositing such a container, an STS crane (STS) or an RTG crane (RTG) is usually used. The STS or RTG crane has a trolley with containerware, also called spreader, on which rotary locks (so-called twist locks) are mounted. The twist locks are provided for engaging into receiving elements (cornercasts) of the container and being fastened therein. After the spreader is fastened to the freight container by means of the twist locks, the freight container can be lifted by means of the trolley of the STS or RTG crane and transported to a desired position at which the container is set down again.The most widely used containers have a length of 20 feet (6.058 m) or 40 feet (12.192 m), wherein the spreader of a crane is generally capable of accommodating one 40 foot container or two 20 foot containers arranged one behind the other. The operator of the crane, however, often cannot reliably distinguish from his cabin whether the container below the spreader is a 40 foot container or two 20 foot containers. The risk is that the crane operator makes a mis decision due to poor / restricted visibility conditions or compliance and using the spreader secures only the outer cornecasts of the two containers with twist locks and the inner cornecasts are not locked. During the subsequent lifting process, the containers can become tilted or, in the worst case, fall down. The result is a costly and therefore costly recovery. This unsafe lifting process also entails a great risk for humans and machines.From the prior art, systems are known which can detect the presence of a gap between two containers to be gripped after placing the spreader on the containers to be gripped. In this position, the upper and lateral surfaces of the containers to be gripped are examined by means of photoelectric sensors. If a gap is detected by means of the sensors, the detection of two 20 foot containers is reported to the crane driver or an automated crane system. Otherwise, a 40 foot container is reported. A disadvantage of this method is that the detection of the containers is possible only in the target position of the spreader and also only when the spreader is positioned almost centrally. As soon as the spreader is on the containers, displaced by a few centimeters orthogonally to the container gap, the sensors which are intended to detect the gap are no longer between the containers. This makes the detection more difficult or impossible and incorrectly reports a 40 foot instead of two 20 foot containers as detectedIt is therefore the object of the invention to improve a device for monitoring a cargo to be loaded, in particular one or more containers.This object is achieved by a device for monitoring a cargo to be loaded, in particular one or more containers according to claim 1.An apparatus according to the invention for monitoring a cargo to be loaded, in particular one or more containers, first comprises at least one sensor, an evaluation unit and an output unit. The sensor is designed to record at least one set of spatial coordinates of measurement points. The measurement points lie in a spatial region which comprises the freight. The evaluation unit is designed to determine at least a part of a contour of the cargo from the set of spatial coordinates of the measurement points and to perform a comparison between the determined contour of the cargo and at least one predefined contour. The output unit is configured to output a signal based on a result of the comparison.The invention has the advantage that a condition of interest of a freight can be checked easily and reliably during a loading operation. In particular, it is not necessary to grasp the entire contour of the cargo, but rather only that part of a contour which is to be compared with the predefined contour, which can likewise preferably have only a part of the contour of the cargo to be loaded, for example a longitudinal or cross section. This significantly simplifies both data recording and data analysis. This enables an increase in the overall operational efficiency of cargo and in particular container terminals by increased safety during handling of the cargo or container and an increase in the throughput in the dynamic and complex environment of the container turnover.The predefined contour can preferably be part of a contour of an upper side, in particular a length, of a cargo, for example a container. The top side of a freight is usually easy to detect, in particular when the sensor is arranged above the freight, for example on a crane for loading the freight. The term contour is to be construed broadly in the sense of the present invention and comprises not only the exact contour of a freight, for example the typical, corrugated surface structure of a freight container, but also, for example, a length or width of an upper side of a freight.A first predefined contour can preferably comprise a part of an upper side of an individual container and / or a second predefined contour can comprise a part of an upper side of two containers arranged one behind the other. By comparing the determined contour of the cargo with the predetermined contour or contours, a condition of the cargo can be determined in a simple manner and information about the cargo can be output, which facilitates the further treatment of the cargo during loading. Thus, for example, the contour of the top side of an individual container differs from the contour of the top side of two containers arranged one behind the other in that there is a gap between the two containers arranged one behind the other. It is thus possible in a simple manner to distinguish whether the sensor has detected a single container or two containers arranged one behind the other.A first predefined contour can preferably comprise a part of an upper side of a 40 foot container and / or a second predefined contour can comprise a part of an upper side of a 20 foot container and / or a third predefined contour can comprise a part of an upper side of two 20 foot containers arranged one behind the other. By comparing the determined contour of the cargo with the predetermined contour or contours, the length and number of containers to be loaded can thus be determined in a simple manner. Thus, for example, the contour of the top side of a 40 foot container differs from the contour of the top side of two 20 foot containers arranged one behind the other with substantially the same length in that a gap exists between the 20 foot containers. In the region of this gap, the contour and thus the spatial position of the measurement points detected by the sensor differ significantly from the spatial position of the measurement points which are detected at a comparable location of a 40 foot container. It is thus possible to distinguish in a simple manner whether the sensor has detected a 20 foot container, a 40 foot container or two 20 foot containers arranged one behind the other.The sensor can be designed as a LIDAR sensor, with which a predetermined spatial range, which is predetermined by the field of view of the LIDAR sensor, can be scanned. The sensor can thus be designed for distance measurement, for example by measuring the time of flight of light pulses transmitted by the sensor. By means of each distance measurement, the spatial position of, for example, a measurement point of the surface of the container can be determined as spatial coordinates.In one embodiment of the invention, the sensor can be designed as a 2D LIDAR sensor, wherein a light beam generated by a laser periodically scans a predetermined spatial region with the aid of a deflection unit. The light is remitted at objects in the spatial region (e.g. the surface of a container) and evaluated in the scanner. From the angular position of the deflection unit, the angular position of the object and from the time of flight using the speed of light, the distance of the object from the laser scanner is additionally deduced. The angle and distance information is used to record the location of an object in the spatial area in two-dimensional polar coordinates. The positions of objects can thus be determined or their contour can be determined. A 2D LIDAR sensor makes it possible to ascertain a contour of the cargo along a line, which is already sufficient for a large number of applications such as the above-described distinction of a 40 foot container from two 20 foot containers arranged one behind the other. In particular, a distance between two containers can also be determined. This information is necessary, for example, for a correct positioning when loading containers onto a truck trailer.In an alternative embodiment of the invention, the sensor can be designed as a 3D LIDAR sensor, wherein a relative movement in the transverse direction is likewise detected, for example by a further degree of freedom of movement of the deflection unit in the laser scanner. Thus, a contour of the cargo can be determined along a plurality of lines spaced apart from one another in space. This enables redundant evaluation and thus more accurate results in the determination of the contour of the cargo. A 3D LIDAR sensor may be further configured to completely sense a top side of the cargo. In the case of a cargo consisting of two containers, it is thus also possible to detect a lateral displacement of the containers relative to one another, that is to say a displacement perpendicular to the longitudinal axis of the containers.The sensor can preferably be mounted on a so-called spreader, i.e. a lifting harness of a crane which is provided for receiving the cargo. The sensor can then detect a contour of the top side of the cargo when lowering the spreader onto the cargo. Typical LIDAR sensors can detect a field of view of more than 180 degrees, so that as a rule the entire top side of the cargo can be detected until the spreader is placed on the cargo. The signal output by the output unit may include information for setting the spreader. If the cargo consists, for example, of one or more containers, the information can comprise the number and size of the containers, or an indication about the rotary locks (twist locks) to be activated on the spreader in order to secure the container or containers securely to the spreader. Furthermore, the information can comprise a positioning of the spreader relative to the freight.The output unit can preferably be designed to output the signal to an operator of the crane, for example via corresponding display elements or via voice output. The operator is then able to set the spreader correctly to the corresponding freight based on the displayed information. Alternatively or additionally, the output unit can be designed to output the signal to a controller of the crane, for example in the case of an automated crane, wherein the information can additionally be output to an operator for monitoring the automated crane.According to a further embodiment, the evaluation unit can be configured to determine a distance of the cargo from the spreader from the set of spatial coordinates of the measurement points, and the output unit can be configured to output the determined distance to an operator and / or to a controller of the crane. As a result, the cargo can be approached efficiently with the spreader, for example the approach speed of the spreader can be adapted to the distance from the cargo.According to a further embodiment, the evaluation unit can be configured to determine an, in particular longitudinal, offset of the cargo from the spreader from the set of spatial coordinates of the measurement points, and the output unit can be configured to output the offset to an operator and / or to a controller of the crane. As a result, the position of the spreader relative to the cargo can be adjusted during the approach to the cargo.According to a further embodiment, the evaluation unit can be configured to use "prior knowledge" with respect to the freight, for example with respect to a predefined spatial region of the freight or its spatial position, in the determination of the contour of the freight. Such "prior knowledge" can reduce the amount of data to be processed by the evaluation unit. This can reduce the computational complexity required for operating the device. Further, the processing speed may increase.According to a further embodiment, the evaluation unit can be configured to determine an angle between the top side of the freight and a lifting direction in which the freight is lifted by the crane from the set of spatial coordinates of the measurement points, and the output unit can be configured to output the determined angle to an operator and / or to a controller of the crane. As a result, when lifting the cargo, it can be checked whether the cargo is correctly fastened to the spreader. If, for example, the twist locks of the spreader were incorrectly not locked at one end of a container, the crane would only lift the container at one end, so that the angle between the top side of the container and the lifting direction would change during the lifting process. The evaluation unit would detect this angle change. By outputting information about the angle change to the operator or the crane controller, the lifting process can be stopped early if, for example, the angle change exceeds a predefined value and damage to the cargo or the crane is thus avoided.The evaluation unit can be part of the sensor or part of an external control unit, which can also comprise the output unit, for example. The predefined contour or the predefined contours of the cargo can preferably be stored in a memory unit of the evaluation unit.The sensor can have an inertial measurement unit (IMU), wherein the evaluation unit can be designed to receive data from the IMU and to determine a movement of the sensor, in particular relative to the normally stationary cargo. Knowing the sensor movement, multiple sets of spatial coordinates acquired by the sensor can be summed up and thus the robustness of the contour determination can be improved.The sensor can be embodied as a so-called solid state lidar without mechanically movable components for beam deflection. Such a sensor is particularly robust and can have a longer service life than a conventional lidar sensor with a rotating scanning unit, in particular in a harsh working environment.The invention is also explained in more detail below with regard to further features and advantages by way of example on the basis of embodiments and with reference to the appended drawing. The figures of the drawing show in: FIG. 1 shows a schematic illustration of a crane having a device according to the invention for monitoring cargo to be loaded. FIG. 2 shows an exemplary flow diagram for monitoring a cargo to be loaded with a device according to the invention. FIG. 3 shows a schematic illustration of an exemplary embodiment in which the device according to the invention is designed to determine at least one angle between the top side of the cargo and a lifting direction.FIG. 1 shows a schematic illustration of a crane 10 which is provided for loading cargo 12, for example containers 14. For this purpose, the crane 10 comprises a trolley 16, to which a spreader 18 with so-called twist locks 20 is attached for lifting, moving and depositing the cargo. The crane 10 is, for example, an STS (Ship To Shore) crane or an RTG (Rubber Tyred Gantry) crane, as are typically used in modern port installations.A device 22 according to the invention is fastened to the spreader 18 with a sensor 24, which is designed as a LIDAR sensor. The sensor 24 therefore has a laser scanner which detects a certain spatial region on the upper side 26 of the containers 14. The sensor 24 is further designed to acquire a set of spatial coordinates of measurement points 28 from the field of view 30 of the sensor 24, i.e. on the upper side 26 of the containers 14.The sensor 24 is connected to an evaluation unit 32. The connection can be wired or wireless. The evaluation unit 32 is designed to determine at least a part of a contour of the freight 12 from the set of spatial coordinates of the measurement points 28 and to perform a comparison between the determined contour of the freight and at least one predefined contour of the freight 12.An output unit 34 is configured to output a signal based on a result of the comparison, for example to an operator and / or a controller of the crane (not shown).FIG. 2 shows an exemplary flow diagram for monitoring a cargo to be loaded with a device according to the invention.In a first step, at least one set of spatial coordinates of measurement points 28 lying in a spatial area comprising the freight is detected 42 by means of a sensor 24.In a subsequent second step, at least a part of a contour of the cargo 12 is ascertained 44 from the set of spatial coordinates of the measurement points 28, for example using segmentation and clustering methods known from image processing.In a third step, a comparison 46 of the determined contour of the cargo 12 with at least one predefined contour of the cargo 12 takes place, for example a check as to whether the determined contour corresponds to the predefined contour of one or two containers, or whether a length of one container corresponds to the length of a 20 foot container or to the length of a 40 foot container.In a further fourth step, a signal is then output 48 which is output on the basis of a result of the comparison, for example the information as to whether the freight is a 20 foot container, a 40 foot container or two 20 foot containers. Based on the information, an operator or a controller of the crane can adjust the spreader.FIG. 3 shows a schematic representation of an embodiment in which the evaluation unit of the device 22 according to the invention is configured to determine at least one angle 50 between the top side 26 of the cargo, in this case one or more containers 14, and a lifting direction 52, in which the cargo is lifted by the crane.In a), the container 14 is fastened to the twist locks 20 of the spreader 18 in order to be lifted in the lifting direction 52. The angle 50 between the upper side 26 of the container 14 and the lifting direction 50 is in this case at 90 degrees with a certain tolerance, the upper side 26 of the container 14 and the lifting direction 50 thus form a substantially right angle 50.In b), a situation is shown by way of example in which the container 14 is not fastened to the spreader on one side, since, among other things, a twist lock 20 ais not correctly locked. As a result, the container 14 is lifted on only one side, so that the angle 50 between the lifting direction 52 and the upper side 26 of the container 14 changes when the container is lifted. The evaluation unit of the device can detect this angle change and, by output to an operator of the crane or to a crane controller, the lifting process can be stopped early and damage to the cargo or the crane can be avoided.In c), two containers 14 are fastened to the twist locks 20 of the spreader 18 in order to be lifted in the lifting direction 52. The angle 50 between the upper side 26 of the containers 14 and the lifting direction 50 is in this case at 90 degrees with a certain tolerance, the upper side 26 of the container 14 and the lifting direction 50 thus form a substantially right angle 50.In d), a situation is shown by way of example in which the containers 14 are in each case not fastened to the spreader 18 in the middle of the spreader 18. As a result, the containers 14 are in each case only lifted on one side, and the angle 50 between the lifting direction 52 and the upper side 26 of the respective container 14 changes when the containers 14 are lifted. The evaluation unit of the device 22 can record this angle change and, by being output to an operator of the crane or to a crane controller, the lifting process can be stopped at an early stage and damage to the cargo or the crane can be avoided. In addition, in this case the contour of the surface of the cargo 12 formed from the two containers 14 detected by the device 22 also changes. If a corresponding contour is detected by the evaluation unit, an error signal can be output.List of reference characters10 Crane 12 cargo 14 container 16 trolley 18 spreader 20, 20 atwistlock 22 device 24 sensor 26 upper side 28 measurement point 30 viewing area 32 evaluation unit 34 output unit 40 flow diagram 42 detection 44 determination 46 comparison 48 output 50 angle 52 lifting direction

Claims

Device (22) for monitoring a freight (12) to be loaded, in particular one or more containers (14), comprising: at least one sensor (24) which is designed to record at least one set of spatial coordinates of measurement points (28), wherein the measurement points (28) lie in a spatial region which comprises the freight (12), an evaluation unit (32) which is designed to: determine at least part of a contour of the freight (12) from the set of spatial coordinates of the measurement points (28) and to carry out a comparison between the determined contour of the freight (12) and at least one predefined contour, and an output unit (34) which is designed to output a signal based on a result of the comparison.The apparatus (22) of claim 1, wherein the predetermined contour comprises a top of a cargo.The device (22) according to any one of the preceding claims, wherein a first predetermined contour comprises an upper side of an individual container and / or a second predetermined contour comprises an upper side of two containers arranged one behind the other.The device (22) according to claim 1 or 2, wherein a first predefined contour comprises an upper side of a 40 foot container, and / or a second predefined contour comprises an upper side of a 20 foot container, and / or a third predefined contour comprises an upper side of two 20 foot containers arranged one behind the other.The device (22) according to any one of the preceding claims, wherein the sensor (24) is configured as a 2D LIDAR sensor:Device (22) according to one of Claims 1 to 4, wherein the sensor (24) is designed as a 3D LIDAR sensor.The apparatus (22) according to any of the preceding claims, wherein the sensor (24) is mounted on a spreader (18) of a crane (10) provided for receiving the cargo (12).The device (22) according to claim 7, wherein the signal comprises information for adjusting the spreader (18), and the output unit (34) is configured to output the signal to an operator and / or to a controller of the crane (10).The device (22) according to claim 7, wherein the evaluation unit (32) is configured to determine a distance of the cargo (12) from the spreader (18) from the set of spatial coordinates of the measurement points (28), and the output unit (34) is configured to output the distance to an operator and / or to a controller of the crane (10).The device (22) according to claim 7, wherein the evaluation unit (32) is configured to determine a longitudinal offset of the cargo (12) to the spreader (18) from the set of spatial coordinates of the measurement points (28), and the output unit (34) is configured to output the longitudinal offset to an operator and / or to a controller of the crane (10).The device (22) according to claim 7, wherein the evaluation unit (32) is configured to determine from the set of spatial coordinates of the measurement points (28) an angle (50) between the upper side (26) of the freight (12) and a lifting direction (52) in which the freight (12) is lifted by the crane (10), and the output unit (34) is configured to output the determined angle (50) to an operator and / or to a controller of the crane (10).

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