Method for navigating a ground transportation vehicle

Abstract

The invention relates to a method for navigating a ground vehicle (5) in a predetermined area, the method comprising the following method steps: - providing a map (1) of the predetermined area with at least one permanent landmark (2), - when a temporary landmark (10) is created, the temporary landmark (10) is registered in the map (1), - when the temporary landmark (10) is cancelled, the temporary landmark (10) is removed from the map (1), and - navigating the ground vehicle (5) in the predetermined area based on the map with the permanent landmark (2) and the temporary landmark (10). As a result, the navigation of a preferably autonomously or semi-autonomously driven ground vehicle in a predetermined area, for example in a warehouse, is improved and in particular becomes safer and more reliable.

Description

Technical Field

[0001] The present invention relates to a method for navigating a ground vehicle in a predetermined area, the method comprising the following method steps:

[0002] - provide a map of the pre-determined area with permanent landmarks, and

[0003] - Navigate ground transportation in a predetermined area based on a map. Background Art

[0004] Floor transport is a transport device used to transport goods horizontally on the ground. The opposite is an overhead transport device suspended from the top of the workshop or using rails. The term "floor transport" is now used in relevant standards. Other sources also use the term "ground transport unit ". Warehouse logistics managers generally distinguish between trackless ground transport vehicles (such as lift trucks, tractors, forklifts), tracked ground transport vehicles (such as trucks (Loren)), and track-guided ground transport vehicles (such as unmanned conveyor systems). The professional association regulation "DGUV Regulation 68" (formerly BGV D27) provides a stricter definition. According to this, ground transport vehicles are transport devices whose construction is characterized by the fact that these ground transport vehicles: run on wheels on the ground and are freely steerable; are adapted for transporting, towing or pushing loads; and are intended for internal use within the company.

[0005] Due to logistical processes (e.g. moving containers by ground vehicles), the static environment of warehouses, where containers and interchangeable containers are stored, for example, is constantly changing. This affects known localization methods and can lead to erroneous results when navigating autonomous ground vehicles in warehouses.

[0006] In this regard, DE 10 2015 011 358 A1 describes the reality problem of the digital map K that always occurs during autonomous driving based on the digital map K. The environment around the vehicle changes, which leads to misjudgment when positioning is performed based on the digital map K that was created at an early time. For example, problems may occur when using objects that change over time as landmarks. For example, trees may change to a large extent with the change of seasons, so that positioning in winter cannot be achieved based on the digital map K recorded in the summer. Another example is dynamic objects, that is, the following objects, which are immovable during the creation of the digital map K and are therefore detected as relevant objects, but these objects are movable, such as other vehicles, which are no longer located at the location detected during the creation of the digital map K at a subsequent time after the creation of the digital map K. This, for example, involves vehicles in a public parking lot, which appear or disappear in the parking lot at different times due to changes in the parking lot occupancy rate.

[0007] Furthermore, DE 10 2016 211 625 A1 describes a method and a system for using parked vehicles as landmarks to advantageously influence the stability of a vehicle positioning system. Here, a method for creating a digital map for positioning a movable motor vehicle is proposed, wherein at least one parked motor vehicle is used as a landmark provided for positioning. The parked motor vehicle here transmits information about its position on the digital map, in particular about its position relative to at least one second landmark located on the digital map, to a server as a landmark.

[0008] Specifically, DE 10 2016 211 625 A1 explains that the position of the parked vehicle often changes, which may lead to the frequent need to change the digital map in order to ensure the required positioning accuracy. Therefore, in these cases, the vehicle must repeatedly pass the track to detect new objects on the map, which forms a large additional cost. In the method for establishing a digital map to locate a moving motor vehicle, at least one stopped motor vehicle is used as a landmark set for positioning. The stopped motor vehicle transmits information about its position on the digital map, especially about its position relative to at least one second landmark located on the digital map, to the server as a landmark. Through this so-called communication, the stopped motor vehicle can transmit its position from itself and does not have to be detected by other motor vehicles first. As a result, the reality of the digital map is better guaranteed, which in turn improves the positioning accuracy of the motor vehicle using the digital map.

[0009] DE 10 2017 105 086 A1 describes how the updating of landmark maps should be improved. To this end, a vehicle is driven into an area, the area is recorded by the vehicle to obtain area data, and vehicle position data of the vehicle in the area are obtained. The presence or disappearance of landmarks that have changed in the area data relative to the landmark map are determined with reference to the vehicle position data. Finally, the landmark map is updated relative to the landmarks.

[0010] DE 10 2015 011 467 A1 describes a method for creating a digital map of a parking space. According to the invention, a digital map is created by means of a plurality of vehicles detecting map data and parking space trajectory data relating to the parking space and transmitting them to a control center, wherein the control center transmits the digital map and the corresponding parking space trajectory to the vehicle to be parked.

[0011] The object of the present invention is therefore to improve the navigation of a preferably autonomously or semi-autonomously travelling ground vehicle in a predetermined area, for example in a warehouse, and in particular to make it safer and more reliable. Summary of the invention

[0012] This object is achieved by a navigation method. Preferred improvements of the present invention are described in the detailed description.

[0013] Therefore, according to the present invention, a method for navigating a ground vehicle in a predetermined area is proposed, the method comprising the following method steps:

[0014] - providing a map of a predetermined area having at least one permanent landmark,

[0015] -When a temporary landmark is created, the temporary landmark is registered in the map,

[0016] - when the temporary landmark is cancelled, the temporary landmark is removed from the map, and

[0017] - navigating the ground transportation vehicle in the predetermined area on the basis of the map having the permanent landmark and the temporary landmark.

[0018] Therefore, a method is provided, which can also be used, for example, in very frequently used warehouses, in which, for example, ground transport vehicles, interchangeable boxes, trailers and / or containers are temporarily stored. The invention makes it possible to also take these landmarks, which are only temporarily present, into account during navigation, which makes navigation simpler, safer and more reliable. In particular, according to a preferred improvement of the invention, it is provided that the map has a plurality of temporary landmarks. Likewise, according to a preferred improvement of the invention, it is provided that the map has a plurality of permanent landmarks.

[0019] Preferably, the temporary landmark is a stored ground vehicle, a stored interchangeable box, a stored trailer or a stored container. In addition, the method is preferably used for a plurality of ground vehicles to be navigated and a plurality of temporary landmarks, and is particularly preferably used for a plurality of ground vehicles at least partially simultaneously.

[0020] In principle, permanent landmarks can be registered in the map in different ways, for example with the aid of separate coordinate points. However, according to a preferred improvement of the present invention, permanent landmarks are registered in the map with the aid of geographic coordinates, which describe the position of the two-dimensional spatial extension or the three-dimensional spatial extension of the permanent landmark. In particular, in the case of large permanent landmarks, further improvements in the accuracy and reliability of the navigation of ground transportation vehicles can be achieved thereby. It is preferably proposed that an identifier that uniquely identifies a temporary landmark is associated with the geographic coordinates that describe the two-dimensional spatial extension or the three-dimensional spatial extension of the temporary landmark. According to a preferred design of the present invention, the geographic coordinates of the temporary landmark may include at least one satellite-based or radio-based geographic coordinate of the storage location of the established landmark.

[0021] According to a preferred improvement of the present invention, when a temporary landmark is established, the step of registering the temporary landmark into the map includes the following:

[0022] - transmitting to the map an identifier that uniquely identifies the temporary landmark, and

[0023] - transmitting at least one geographical coordinate of the created temporary landmark to the map.

[0024] Here, the identifier of the landmark preferably includes the type of landmark, for example the type or size of the pallet or the type or size of the container. However, the geographical coordinates of the temporary landmark to be created can also simply be an identifier, for example the number of the storage place, which uniquely identifies the storage place. Therefore, it is also preferably proposed in this regard that the geographical coordinates include an identifier that uniquely identifies the storage place of the temporary landmark to be created.

[0025] Likewise, the identifier that uniquely identifies the stored landmark may be a number that uniquely identifies the landmark, such as a container number that uniquely identifies a shipping container made according to ISO 668. This container number consists of an owner code or operator code, a classifier, a serial number, and a checker.

[0026] In addition, according to a preferred improvement of the present invention, when a temporary landmark is established, the step of registering the temporary landmark into the map further includes:

[0027] - registering the geometrical and / or optical properties of the temporary landmark into the map.

[0028] This can simplify the retrieval of the temporary landmark or the identification of the temporary landmark when the temporary landmark is to be removed again, ie to be cancelled again.

[0029] According to a preferred design solution of the present invention, the step of establishing a temporary landmark includes the following steps:

[0030] -Classify and / or measure temporary landmarks for re-identification.

[0031] The classification of temporary landmarks can be performed, for example, with respect to the type of landmark, ie, for example, with respect to classification as a forklift, container or pallet. The classification of temporary landmarks and the measurement of temporary landmarks can simplify the re-identification of temporary landmarks when they are to be removed again.

[0032] Furthermore, it is preferably proposed that the step of establishing a temporary landmark includes the following steps:

[0033] - estimating the storage position of the temporary landmark according to the posture of the ground transportation vehicle.

[0034] In this way, the storage location does not have to be determined individually, but only information about the ground vehicle (ie its attitude) is required.

[0035] Furthermore, it is preferably proposed that the step of cancelling the temporary landmark includes the following steps:

[0036] - identifying the temporary landmark by the ground vehicle by means of an optically discernible feature of the temporary landmark, and

[0037] - Delivering the temporary landmark by ground transportation after positively identifying the temporary landmark.

[0038] It is particularly preferably applicable here if the optically discernible feature of the temporary landmark is formed by an optically discernible code applied or mounted on the temporary landmark and / or by properties of a hubcap of the temporary landmark.

[0039] It further applies that when cancelling a temporary landmark, the step of cancelling the temporary landmark preferably comprises the following steps:

[0040] - Estimate the pose of temporary landmarks.

[0041] This simplifies the transport of the temporary landmark by ground transport. Preferably, the step of estimating the pose of the temporary landmark is here implemented by means of scan matching and / or by means of particle filtering, wherein in principle all standard algorithms are of course possible.

[0042] According to a preferred improvement of the present invention, it is also proposed that the step of transmitting the geographical coordinates of the created temporary landmark to the map is carried out by the created temporary landmark itself or by the ground transport vehicle that has created the temporary landmark. This makes the method particularly simple, because in this way no additional equipment for the method according to the present invention needs to be provided.

[0043] In principle, the map can be managed in different places, for example in a ground vehicle or also in multiple ground vehicles at the same time. However, according to a preferred improvement of the invention, the map is managed centrally in a central unit. When a temporary landmark is created, the temporary landmark is registered in the map, which means that the corresponding information is transmitted to the central unit. This central unit, which is almost a common server, simplifies the method and reduces the hardware expenditure.

[0044] The registration of a temporary landmark in the map can be performed at different times and occasions. According to a preferred design of the present invention, the step of registering the temporary landmark in the map when the temporary landmark is established and the step of removing the temporary landmark from the map when the temporary landmark is cancelled are performed in real time. In this way, a particularly large benefit can be obtained from the map, because there is actually always current map data reflecting the current situation in the predetermined area.

[0045] In principle, permanent landmarks are considered to be completely different facilities. Preferably, permanent landmarks are formed by buildings, terrain objects, signs, signs or boundaries of predetermined areas. It is also applicable that the ground vehicle is preferably an autonomous or semi-autonomous vehicle.

[0046] It is also preferably provided that for navigation the vehicle determines its position with the aid of a map using satellite-based or radio-based coordinates, for example using DGPS coordinates. For navigation relative to other non-parked vehicles, the ground vehicle is preferably equipped with an optical camera, a LIDAR sensor and / or an ultrasonic sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention will be explained in more detail below with reference to the accompanying drawings using preferred exemplary embodiments.

[0048] In the attached picture:

[0049] Figure 1 Schematically shows a map with permanent landmarks according to a preferred embodiment of the present invention,

[0050] Figure 2 Schematically shows a central unit according to the presently described preferred embodiment of the invention, which communicates by radio with a plurality of ground vehicles,

[0051] Figure 3 A ground transport vehicle according to the presently described preferred embodiment of the invention is schematically shown,

[0052] Figure 4 schematically shows a map with permanent and temporary landmarks according to the presently described preferred embodiment of the invention, and

[0053] Figure 5 Schematically shows Figure 4 , from which the temporary landmarks were again removed. DETAILED DESCRIPTION

[0054] With regard to the preferred embodiments of the present invention described herein, Figure 1 The warehouse area can be seen schematically in Figure 1 The warehouse has a substantially rectangular outer boundary 3 within which a plurality of permanent landmarks 2 have been registered. Figure 1 The geographical coordinates of the two-dimensional boundaries of these permanent landmarks 2 and the geographical coordinates of the outer boundary 3 of the warehouse are given. These permanent landmarks can be, for example, buildings, terrain objects, marks and signs. The permanent landmarks 2 have in common that they define the area of ​​the warehouse in which the ground transport vehicles 5 can move. In other words, the permanent landmarks 2 form obstacles that the ground transport vehicles 5 must take into account when driving in the warehouse and when navigating accordingly in the warehouse. In addition, the outer boundary 3 of the warehouse naturally also forms a permanent landmark in fact, because the ground transport vehicles 5 should not or cannot drive beyond this outer boundary 3 when driving in the warehouse.

[0055] As from Figure 2 As can be seen schematically in the figure, this Figure 1 The warehouse is centrally stored and managed in a central unit 4. This central unit 4 is connected to all ground transport vehicles 5 moving in the warehouse via radio. Figure 2 The radio connection is shown by a dotted line in FIG. 5 . All these ground vehicles 5 access the ground in this way. Figure 1 , and therefore access based on Figure 1 In addition, the ground vehicle 5 can also send information to the central unit 4 based on its corresponding radio connection with the central unit 4 to update or supplement the map data. Figure 1 With the permanent landmarks 2 of the warehouse (as shown above) and the outer boundary 3 of the warehouse, it is possible for the ground vehicle 5 to navigate within the warehouse without colliding with the permanent landmarks 2.

[0056] exist Figure 3Schematically, one of the ground vehicles 5 moving within a warehouse is shown. This ground vehicle 5 has a GPS receiver 6 for satellite navigation. With the help of satellite navigation, the ground vehicle 5 can determine the geographical coordinates of the place where it happens to be. This allows the ground vehicle 5 to use the GPS receiver 6 to determine the geographical coordinates of the place where it happens to be located. Figure 1 Navigation in the warehouse. In addition, the ground vehicle 5 has further sensors, namely an optical camera 7, a LIDAR sensor 8 and a plurality of ultrasonic sensors 9. These further sensors allow the ground vehicle 5 to detect its real-time environment, so that other ground vehicles 5 traveling in the warehouse can also be detected and can be considered dynamic for navigation in the warehouse. Overall, fully autonomous driving of the ground vehicle 5 in the warehouse is allowed.

[0057] Furthermore, the ground vehicle 5 has a radio unit 11 in order to be able to communicate with the central unit by radio. Figure 3 The other ground transport vehicles 5 for the warehouse shown schematically are correspondingly equipped with a radio unit 11 for communicating with the central unit 4, a GPS receiver 6 for satellite navigation, as well as an optical camera 7, a LIDAR sensor 8 and a plurality of ultrasonic sensors 9 in order to be able to detect the dynamically changing environment of these ground transport vehicles.

[0058] In the preferred embodiment of the invention described here, the purpose of the ground vehicle 5 is to store facilities (e.g. containers, interchangeable boxes and pallets) in the warehouse and to subsequently remove them again when required. These facilities stored at least temporarily in the warehouse form temporary landmarks, so that the ground vehicle 5 must also take these temporary landmarks into account when navigating in the warehouse. In addition, when a facility is to be removed again, the ground vehicle 5 needs information about the location where this facility is stored. In the case of the preferred embodiment of the invention described here, it is provided that, as schematically shown in FIG. Figure 4 As shown in FIG. 1 , when a temporary landmark is established, the temporary landmark 10 is registered on the ground. Figure 1 In the example of FIG. 4 , the map is centrally retained and managed in the central unit 4. From a previously empty warehouse (i.e. a warehouse that does not yet contain temporary landmarks, such as in Figure 1 ) shown in the beginning, Figure 4 Now three temporary landmarks 10 are shown, corresponding to three facilities which have been stored in the warehouse in the meantime by means of ground transport 5. The temporary landmarks 10 are here interchangeable boxes stored in the warehouse.

[0059] Now register the temporary landmark 10 to the ground Figure 1In the embodiment, the method is as follows: after storing the replaceable box, the ground transportation vehicle 5 (which has stored the corresponding replaceable box in the warehouse) immediately notifies the central unit 4 by radio that it has stored the replaceable box in the corresponding storage place. To this end, the ground transportation vehicle 5 transmits the unique identifier of the corresponding replaceable box and the geographical coordinates of the stored replaceable box to the central unit 4, and these geographical coordinates represent the outer boundaries of the storage area of ​​the corresponding replaceable box in two dimensions. This information is correspondingly registered in the central unit 4 to the geographical coordinates. Figure 1 middle.

[0060] Instead of geographic coordinates, it is also possible to transmit only the identifier of the storage location, i.e., for example, “parking space 45”, when storing information in the central unit 4 that gives information about where to find the corresponding storage location in the map. It is also possible to transmit only the type of interchangeable box (e.g., “type C”) or the size of the interchangeable box (instead of the unique identifier of the interchangeable box) to the central unit 4. When the type of interchangeable box is transmitted to the central unit 4, it is naturally necessary to store information in the central unit 4 again that allows the description of the type of interchangeable box to be registered as a temporary landmark 10 in the map. Figure 1 In this way, it is possible to identify which space or which surface the replaceable box occupies in the warehouse and which space or surface must be considered as inaccessible when the ground vehicle 5 is driving in the warehouse.

[0061] Finally, from Figure 5 As can be seen in FIG. 1 , when the temporary landmark is cancelled, that is, when the corresponding replaceable box is taken away and removed from the warehouse or when the warehouse is reversed, it is also removed from the ground again. Figure 1 Remove the registration address Figure 1 Temporary landmark 10. Figure 5 As can be seen in Figure 4 Still in the ground Figure 1 The two temporary landmarks 10 shown in the upper right of FIG. 1 no longer exist because they were removed from the warehouse by the ground transport 5. Figure 1 The removal of these temporary landmarks 10 is carried out as follows: immediately after the corresponding interchangeable box is loaded onto the ground transport vehicle 5, the corresponding ground transport vehicle 5 notifies the central unit 4 by radio that the interchangeable box is no longer located at its current storage location, and thus cancels the corresponding temporary landmark 10.

[0062] Overall, the navigation of autonomously traveling ground vehicles 5 in a warehouse is significantly improved in a simple manner, i.e. becomes safer and more reliable, since the ground vehicles 5 traveling in the warehouse register these temporary landmarks in the ground in real time when temporary landmarks 10 (in the form of replaceable boxes) are created or removed again. Figure 1In or remove these temporary landmarks again.In addition, the method described here can also significantly simplify the search and transportation of replaceable boxes.

[0063] List of Reference Numerals

[0064] 1 Map

[0065] 2 Permanent landmarks

[0066] 3 Outer boundary

[0067] 4 Central Unit

[0068] 5 Ground transportation

[0069] 6 GPS receiver

[0070] 7 Optical Camera

[0071] 8 LIDAR Sensor

[0072] 9 Ultrasonic Sensor

[0073] 10 Temporary Landmarks

[0074] 11 Radio Unit

Claims

1. A method for navigating a ground vehicle (5) in a predetermined area, the method comprising the following method steps: - providing a map (1) of a predetermined area having at least one permanent landmark (2), wherein the map (1) is managed in a central unit (4) located outside the ground transport vehicle (5), - when a temporary landmark (10) is established, registering the temporary landmark (10) in the map (1), wherein the temporary landmark (10) is a stored ground transportation vehicle, a stored interchangeable box, a stored trailer or a stored container, - when the temporary landmark (10) is cancelled, the temporary landmark (10) is removed from the map (1), and - navigating the ground transport vehicle (5) in the predetermined area based on a map having the permanent landmark (2) and the temporary landmark (10), wherein When the temporary landmark (10) is established, the step of registering the temporary landmark (10) into the map (1) comprises: at least one geographical coordinate of a temporary landmark (10) created is transmitted to the map (1), wherein the temporary landmark (10) also determines its geographical coordinates, and wherein The step of transmitting at least one geographical coordinate of the created temporary landmark (10) to the map (1) is performed by the created temporary landmark (10) itself, The step of registering the temporary landmark (10) in the map (1) when the temporary landmark (10) is established and / or the step of removing the temporary landmark (10) from the map (1) when the temporary landmark (10) is cancelled are performed in real time.

2. The method according to claim 1, wherein the permanent landmark (2) and / or the temporary landmark (10) is registered in the map (1) with the aid of geographic coordinates, which describe the position of the two-dimensional spatial extension or three-dimensional spatial extension of the permanent landmark (2) or the temporary landmark (10).

3. The method according to claim 1, wherein when the temporary landmark (10) is established, the step of registering the temporary landmark (10) in the map (1) comprises: - transmitting to the map (1) an identifier that uniquely identifies the temporary landmark (10).

4. The method according to any one of the preceding claims 1 to 3, wherein the step of registering the temporary landmark (10) in the map (1) when establishing the temporary landmark (10) further comprises: - registering the geometrical and / or optical properties of the temporary landmark (10) in the map (1). 5 . The method according to claim 1 , wherein the ground vehicle ( 5 ) is an autonomous or semi-autonomous vehicle.

6. The method according to any one of claims 1 to 3, wherein the step of establishing the temporary landmark (10) comprises the following steps: - classifying and / or measuring the temporary landmark (10) for re-identifying the temporary landmark (10), and - Register the classification results or measurement results in the map (1).

7. The method according to any one of claims 1 to 3, wherein the step of establishing the temporary landmark (10) comprises the following steps: - estimating the storage position of the temporary landmark (10) based on the posture of the ground transportation vehicle (5), and - Registering the estimated storage location of the temporary landmark (10) into the map (1).

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