WAREHOUSE INSPECTION SYSTEM

Abstract

System for inspecting a warehouse 50 comprising: a laser scanner 52 attachable to an industrial truck 1 and adapted to scan in a plane E substantially perpendicular to the industrial truck's main direction of travel G in order to scan an environment of a warehouse on at least one side, preferably both sides, of the industrial truck and to generate scan data based thereon, a computing unit 60 adapted to receive the scan data and data on the absolute position and/or relative position change of the industrial truck, or data from which one or more of these variables can be derived, the computing unit 60 being further adapted to construct three-dimensional data of the environment on the basis of the scan data and data on the absolute position and/or relative position change of the industrial truck.

Claims

1. A system for inspecting a warehouse (50) comprising: a laser scanner (52) attachable to an industrial truck (1) and adapted to scan in a plane (E) substantially perpendicular to the industrial truck's main direction of travel (G) in order to scan an environment of a warehouse on at least one side, preferably both sides, of the industrial truck and to generate scan data based thereon, a computing unit (60) that is adapted to receive the scan data and data on the absolute position and/or relative position change of the industrial truck, or data from which one or more of these variables can be derived, wherein the computing unit (60) is further adapted to construct three-dimensional data of the environment based on the scan data and data on the absolute position and/or relative position change of the industrial truck.

2. System according to claim 1, wherein the computing unit (60) is adapted to receive odometry data of the industrial truck (70), data on the absolute position and/or relative position change of the industrial truck being derived from the odometry data of the industrial truck (70).

3. System according to claim 1 or claim 2, wherein the laser scanner (52) has scanning directions that include the two horizontal directions (H1 and H2) and the vertical upward direction (V1).

4. System according to one of the preceding claims, wherein the computing unit (60) is further adapted to detect individual storage elements from the constructed three-dimensional data of the environment.

5. System according to one of the preceding claims, wherein the computing unit (60) is further adapted to receive data from a warehouse management system.

6. System according to claim 4 and claim 5, wherein the computing unit (60) is further adapted to check a storage condition based on a comparison of the three-dimensional data of the individual detected storage elements with corresponding data from the warehouse management system.

7. System according to one of claims 4 to 6, wherein the computing unit (60) is further adapted to check a storage condition based on a comparison of the three-dimensional data of the individual detected storage elements with predefined reference data.

8. System according to claim 6 or claim 7, wherein the computing unit (60) is further adapted to document the storage condition and/or output instructions based on the storage condition.

9. Industrial truck (1) comprising a system (50) according to one of claims 1-8.

10. Industrial truck (1) according to claim 9, wherein the industrial truck is a track-guided industrial truck.

11. Industrial truck according to claim 9 or claim 10, wherein the industrial truck comprises a mast, the laser scanner being fixed to an attachment of the industrial truck that is directly or indirectly movably connected to the mast, the height of the laser scanner being adjustable in relation to the driving surface with a work function of the industrial truck.

12. Industrial truck (1) according to one of claims 8-10, wherein the industrial truck is preferably a high-bay stacker comprising an operator's station (12) with an overhead guard (22) and/or a load carrying apparatus (36) that can be moved laterally back and forth, transverse to the truck's straight-ahead direction of travel (2), the laser scanner (60) preferably being fixedly attached to the overhead guard (22) or to the load carrying apparatus (36).

13. A method for inspecting a warehouse by means of a system (50) according to one of claims 1-8, wherein the system (50) can be assigned to an industrial truck (1) according to one of claims 9-12, comprising: Scanning the environment and generating scan data; Capturing data on the absolute position and/or relative position change of the industrial truck, or data from which one or more of these variables can be derived; Constructing three-dimensional data of the environment based on the scan data and odometry data of the industrial truck (70).

14. Method according to claim 13, further comprising: Capture of odometry data of the industrial truck (70), data on the absolute position and/or relative position change of the industrial truck being derived from the odometry data of the industrial truck (70).

15. Method according to claim 13 or claim 14, further comprising: Automatic activation of the system when a reference point is detected.

16. Method according to one of claims 13-15, further comprising detection of the current spatial position of the laser scanner (52), for example based on externally input data or reference points detected by the laser scanner, the method further including the construction of three-dimensional data of the environment based on the spatial position of the laser scanner.

17. Method according to one of claims 13-15, wherein the method further comprises: Detection of individual storage elements from the constructed three-dimensional data of the environment.

18. Method according to one of claims 13-16, further comprising: Reception of data from a warehouse management system.

19. Method according to claim 17, further comprising: Inspection of a storage condition based on a comparison of the three-dimensional data of the individual detected storage elements with corresponding data from the warehouse management system.

20. Method according to one of claims 16 to 18, further comprising: Inspection of a storage condition based on a comparison of the three-dimensional data of the individual detected storage elements with predefined reference data.

21. Method according to claim 19 or claim 20, further comprising: Detection of damage or irregularities of the storage condition.

22. Method according to one of claims 19-21, further comprising: Output of instructions based on the storage condition and, where necessary, re-establishing a proper storage condition.

23. Method according to one of claims 13-22, wherein the method is carried out during a deposit or retrieval operation.

Description

DESCRIPTION OF DRAWINGS

[0046] FIG. 1 A side view of an exemplary embodiment of an industrial truck with a system for inspecting a warehouse according to the invention.

[0047] FIG. 2 A schematic diagram of the scanning plane of the laser scanner from FIG. 1.

[0048] FIG. 3 A schematic diagram of the components provided for the inspection of a warehouse with the exemplary embodiment of FIG. 1.

[0049] FIG. 4 A schematic diagram illustrating the detection of damage in a warehouse using the system in FIG. 1.

[0050] FIG. 5 A schematic diagram illustrating the detection of an irregularity in a warehouse using the exemplary embodiment of FIG. 1.

[0051] FIG. 6 A schematic diagram illustrating a deposit strategy used in conjunction with the exemplary embodiment of FIG. 1.

[0052] FIG. 7 A schematic diagram illustrating another deposit strategy used in conjunction with the exemplary embodiment of FIG. 1.

[0053] FIG. 1 shows a side view of an exemplary embodiment of an industrial truck 1 with a system for inspecting a warehouse according to the invention, in which exemplary embodiment the industrial truck is a high-bay stacker designed as a trilateral forklift.

[0054] The industrial truck 1 has wheels 2 mounted on wheel suspensions, not shown, which stand on the driving surface 4. The wheel suspensions are in turn attached to a vehicle body 6 to which an upright-mounted mast 8 is also attached. The mast 8 is designed to be telescopically extendable in multiple parts, as illustrated in FIG. 1 by the extended position shown with dotted lines. On the furthest extendable telescope stage 10 of the mast 8, a vertically movable support structure 9 is attached to support the operator's station. The support structure 9 has a cantilever arrangement 24 projecting forward from the mast 8 in the main direction of travel G of the industrial truck as a jib supporting a platform 11 of an operator's station 12 on its underside and carrying a side shift frame 34 at its projecting end.

[0055] The operator's station 12 is designed as a liftable operator's cab, whose frame has a rear wall, side walls and overhead guard 22, with the operator's station platform 11 forming the cab floor. The side shift frame 34 is attached to the cantilever arrangement 24 in front of the operator's station 12 viewed in the main direction of travel G. The side shift frame 34 is part of a load-carrying assembly 36, known per se, which further comprises a side shift device 38 disposed on the side shift frame 34 so as to be movable laterally, transverse to the truck's straight-ahead direction of travel G, in the form of a swivel push device 38 with an additional mast 40 arranged in front of it, on which a load-carrying fork 42 with a fork-carrier arrangement is vertically movable as a load-carrying element. The additional mast 40 can be swiveled together with the load carrying fork 42 about the vertical axis 44 between the position shown in FIG. 1, with lateral alignment of the load carrying fork 42 or its load carrying tines 43 (transverse alignment to the left in relation to the straight-ahead direction of travel G), and a position with opposite lateral alignment (transverse alignment to the right) of the load carrying tines 43.

[0056] All work functions associated with the mast 8 and the load carrying assembly 36 are operable by means of a hydraulic unit, not shown.

[0057] The industrial truck 1 includes a system for inspecting a high-bay warehouse, the system comprising a laser scanner 52 and a computing unit 60, not shown in FIG. 1. The system preferably serves as an extension of the industrial truck, wherein the computer unit 60 can either be assigned to an already existing on-board computer of the industrial truck 1 or can be provided by a separate computer system. The laser scanner 52 is fixed to the industrial truck, preferably to an attachment that is directly or indirectly movably connected to the mast 8, the height of the laser scanner 52 being adjustable in relation to the driving surface 4 with a work function of the industrial truck 1. The laser scanner 52 is preferably fixed on top of the side shift device 38. Alternative locations such as the overhead guard 22 are also suitable for mounting the laser scanner 52. The laser scanner 52 is adapted to perform a scan in a plane E substantially perpendicular to the industrial truck's main direction of travel G.

[0058] FIG. 2 shows the scanning plane E of the laser scanner viewed in the industrial truck's main direction of travel G. The laser scanner 52 preferably has a continuous scanning range 54 of more than 180° and is currently positioned at a certain height h in relation to the driving surface 4 such that the scanning directions of the laser scanner 52 comprise the two horizontal directions H1 and H2 and the vertical upward direction V1. This means that rack fronts of racks 80 and 82 on both sides of the industrial truck 1 can be captured with a single measuring run. Furthermore, the scanning beam of the laser scanner 52 can reach rack fronts from the rack floor to the highest levels of racks 80 and 82, so that all storage locations on both sides of the lane can be detected at once. The system can therefore be particularly advantageous and time-saving, for example when conducting an inventory of a warehouse or inspecting the occupancy status of storage locations.

[0059] FIG. 3 contains a rough schematic diagram illustrating the structure of the system 50 for inspecting a warehouse that is used in the industrial truck 1 shown in FIG. 1. The system 50 includes the laser scanner 52 and the computing unit 60, the laser scanner 52 being disposed to scan the environment in order to generate scan data, and the computing unit 60 being disposed to receive the scan data and construct three-dimensional data of the environment based on these. Since the scanning plane E is perpendicular to the industrial truck's main direction of travel G, data on the spatial position or direction of movement of the laser scanner 52 are additionally needed to construct three-dimensional data of the environment. According to the invention, the computing unit 60 is disposed to receive odometry data of the industrial truck 70, the odometry data of the industrial truck 70 comprising position and orientation data of the vehicle, which can preferably be determined by means of its propulsion system.

[0060] Since the laser scanner 52 is fixedly attached to the industrial truck 1, the direction of movement of the laser scanner 52 results from the direction of travel of the industrial truck 1 and thus directly from the odometry data of the industrial truck 70. In order to determine the spatial position of the laser scanner during scanning, other data may be relevant and consulted in addition to the odometry data 70.

[0061] Since the laser scanner 52 is preferably fixedly attached to an attachment of the industrial truck 1 that is directly or indirectly movably connected to the mast 8, the height of the laser scanner h in relation to the driving surface 4 can be adjusted with a work function, for example the lifting or lowering of a load carrying element of the industrial truck 1. Furthermore, the horizontal position of the laser scanner can also be changed by means of a work function, for example the swiveling of a load carrying element. This means that the relative position of the laser scanner 52 changes with respect to the body 6 of the industrial truck 1. Data 72 corresponding to the work function with respect to, for example, the positioning data of an attachment can be obtained, for example, from a control unit of the industrial truck and/or from a warehouse management system and are preferably used when determining the spatial position of the laser scanner 52.

[0062] Further data 74, for example relating to environmental influences such as ground unevenness or reference data for the localization of the industrial truck, can also be relevant for the determination of the spatial position of the laser scanner, such further data 70 being obtainable with various pre-existing or separately added sensor-based solutions.

[0063] Based on the scan data, the odometry data of the industrial truck and possibly other data mentioned above, the computing unit 60 constructs three-dimensional data of the environment in the form of a point cloud. Through suitable image processing, the computing unit 60 can recognize various storage elements from the constructed point cloud and, based on these, determine three-dimensional data of the individual recognized storage elements. Based on a comparison of the three-dimensional data of individual detected storage elements with corresponding data from the warehouse management system and/or with predefined reference data, the computing unit 60 is able to automatically detect damage or irregularities in a warehouse. FIG. 4 and FIG. 5 each illustrate an example of this.

[0064] FIG. 4 shows part of a rack 84 comprising a plurality of horizontal supports 86 and vertical supports 88. It can be seen in FIG. 4 that rack damage has occurred in the form of a deformed horizontal support 86. When the industrial truck 1 with the system 50 passes the affected storage area, the computing unit 60 is able to recognize, from the constructed point cloud and corresponding image processing algorithms, that the horizontal support 86 is deformed. Based on this, the computing unit 60 can output an instruction to have the horizontal beam 86 repaired or replaced.

[0065] FIG. 5 also shows part of a rack 84 with horizontal supports and vertical supports. It can be seen from FIG. 5 that two deposited load units 90 and 92 are deformed in such a way that the load unit 94 is compressed by the other two and has also been deformed as a result. If the load unit 94 were to be retrieved by an automated industrial truck without taking this irregularity into account, in the worst case the resulting frictional force could cause the adjacent load units 90 and 92 to fall out of the rack, resulting in an accident.

[0066] However, with the solution according to the invention, this irregularity can be detected before the load unit 94 is retrieved, thereby avoiding a potential accident. When the industrial truck 1 with the system 50 passes the storage area concerned, the computing unit 60 is able to detect that the distance between load units 90 and 94 and the distance between load units 92 and 94 is below a predefined, permitted reference value, which is stored in the warehouse management system, for example. When these irregularities are detected, the computing unit 60 will output an appropriate instruction so that the load unit 94 is not retrieved until this irregularity has been rectified.

[0067] FIG. 6 schematically illustrates a deposit strategy used in conjunction with the exemplary embodiment of FIG. 1. The industrial truck 1 preferably receives a transport order from a warehouse management system, which specifies the destination storage location where a load is to be deposited. Based on this, a navigation system of the industrial truck guides the industrial truck 1 to a target position, the load carrying fork 42 of the industrial truck also being set, if necessary, to a target position by a control system of the industrial truck, so that the load can be deposited in the target storage location.

[0068] Before the industrial truck reaches the target position, the warehouse inspection system 50 is preferably activated and the speed of the industrial truck is reduced, if necessary, so that the target storage location can be scanned when the industrial truck passes the target storage location in direction G, and three-dimensional data of the target storage location can be constructed based on this. The scanning range 100 is marked by dashed lines, the complete target storage location with associated storage carriers and adjacent goods being scanned as shown in FIG. 6. Based on the constructed three-dimensional data of the scanning range 100, the computing unit 60 of the system is able to define the target destination position P.sub.target to be approached by the load carrying fork 42 for the deposit operation, the position P.sub.target corresponding, in the embodiment shown, to a central point in the width direction of the target storage location.

[0069] If the defined target position P.sub.target differs from the specified actual target position of the load carrying fork 42, the specified actual target position is preferably replaced by the desired target position P.sub.target. Subsequently, the updated actual target position of the storage location can be approached, allowing the deposit operation to be carried out.

[0070] However, the strategy described above assumes that the industrial truck 1 drives past the complete target storage location, allowing the whole target storage location to be scanned. To enable deposit after scanning, the industrial truck 1 must move back a certain distance in the direction opposite to the industrial truck's main direction of travel G so that the load carrying fork 42 can approach the actual target position, which may have been updated. To avoid this, for example, an alternative strategy can be used to support a deposit operation which is illustrated in FIG. 7.

[0071] In contrast to the strategy shown in FIG. 6, for example, only one rack support, in this case the vertical support 88 shown in FIG. 7, is scanned and recognized when the target storage location is reached (see scanning range 200). Based on this, the control system of the industrial truck, together with data concerning the dimensions of the target storage bin saved locally or externally (such as in the warehouse management system), can calculate the target destination position P.sub.target. Although the strategy shown in FIG. 7 has the disadvantage that part of the target storage location cannot be scanned, this disadvantage can be compensated, for example, by using additional sensors, such as a camera, which also detects the storage location and/or the environment near the storage location during the deposit operation.

[0072] In addition to the strategies illustrated in FIG. 6 and FIG. 7, a person skilled in the art may also use other strategies for deposit or retrieval operations in conjunction with the industrial truck and/or the method of the present invention, as required.

[0073] It should also be noted that, according to the invention, a partially automated industrial truck or a fully automated driverless industrial truck could also be used as an alternative to the manually operated industrial truck shown in FIG. 1. In the case of a fully automated, track-guided industrial truck, for example, the operator's station 12 shown in FIG. 1 can be dispensed with.