LOADING AND UNLOADING A CARGO AREA WITH A LOADING VEHICLE

Description

[0001] The invention relates to a method for loading and / or unloading a loading space with a loading vehicle and to a safety system for loading and / or unloading a loading space with a loading vehicle according to the preamble of claim 1 or 15.

[0002] Loading and unloading a truck or its trailer at a loading ramp (truck loading) is currently done manually using a manned forklift. It is the forklift driver's responsibility to pay attention to people and avoid accidents. While autonomous vehicles are used in the logistics sector, these vehicles would in principle be capable of handling loading and unloading, or at least enabling a mix of manual and automated operations, there is no solution to ensure that no one is in the trailer during loading and unloading. In other automated applications in logistics, autonomous vehicles only operate in areas restricted to people. This is not feasible at a loading ramp.

[0003] Autonomous vehicles already monitor their progress with sensors to prevent accidents. For example, a protective field is monitored in the direction of travel. If an object is detected in the protective field, a hazardous situation is assumed and the vehicle is braked. Non-contact sensor principles are used for this purpose. Sensors used in accident prevention or safety technology must be particularly reliable and therefore meet stringent safety requirements, such as the EN ISO 13849 standard for machinery safety and the EN / IEC 61496 device standard for electro-sensitive protective devices (ESPE). To comply with these safety standards, a number of measures must be taken, such as secure electronic evaluation using redundant, diverse electronics, function monitoring, or monitoring for contamination of optical components.

[0004] However, conventional protective field monitoring doesn't work in a semi-trailer. For economic reasons, the load is packed very tightly and without empty spaces. Protective field monitoring typically only determines whether the protective field is free of objects. This would almost never be the case inside the semi-trailer, making it virtually impossible for the vehicle to stop. There are already approaches to distinguishing between permissible and non-permissible objects in a protective field, but especially under the dense storage conditions mentioned above, current sensor technology is unable to reliably distinguish between people and cargo.

[0005] US Patent No. 10,815,080 B2 discloses an automatic loading and unloading system for trucks that plans an optimized load layout and controls autonomous vehicles accordingly. However, the document does not address safety aspects.

[0006] Other conventional approaches rely on special installations in the loading area, such as conveyor systems. For example, it is common practice to prepare the entire load outside the truck or trailer in the correct arrangement and then move it as a whole. This approach is therefore limited to special loading infrastructure, and again, safety is not initially considered and therefore must be ensured separately and separately.

[0007] DE 10 2019 128 782 A1 introduces so-called safety points. These are positions that a mobile machine identifies using a localization system and at which a safety function of the mobile machine's safety system is switched. In the case of DE 10 2019 128 782 A1, the localization system is based on a distance sensor and a contour recognition unit. However, the safety points are not related to loading and unloading.

[0008] The document US 2018 / 194575 A1 discloses a system for loading objects in which an automated vehicle is controlled during the loading of objects based on the size of the vehicle to be loaded and the size of the objects to be loaded.

[0009] EP 3 859 382 A1 discloses a method for locating a person or object in a monitored area using a security system. It is based on a radio positioning system with multiple radio stations that detect radio transponders on the person or object. A position-resolving sensor is also provided for position determination. Reliable position data is acquired by comparing the position data of the radio positioning system and the position-resolving sensor. This position determination is described without any connection to loading and unloading.

[0010] It is therefore an object of the invention to simplify the loading or unloading of a cargo space with a loading vehicle.

[0011] This object is achieved by a method for loading and / or unloading a loading space with a loading vehicle and a safety system for loading and / or unloading a loading space with a loading vehicle according to claim 1 and 15, respectively. A loading space is an area, for example, enclosed by walls and therefore only accessible through an access area, in which goods or other objects referred to as loading objects are stored, preferably for transport such as in the case of a container, trailer, or semi-trailer. For this purpose, a loading vehicle drives into the loading space at least once, usually repeatedly, to deposit and / or retrieve at least one loading object. The loading vehicle is preferably an autonomous vehicle, such as an AGV (Automated Guided Vehicle) or an AMR (Autonomous Mobile Robot). Alternatively, the loading vehicle can be driven by a driver.The invention then automatically protects the driver against possible accidents with people or other objects in his work area.

[0012] The access area, which represents the only way into the cargo area, is protected by at least one first sensor. Protection with the first sensor is sometimes referred to below as stationary protection. The loading vehicle itself is protected by at least a second sensor. Protection with the second sensor is accordingly referred to as mobile protection. The stationary and mobile protection together ensure that the loading vehicle does not collide with unexpected objects during loading and unloading and, in particular, prevent accidents involving personal injury.

[0013] The invention is based on the basic idea that stationary and mobile security complement each other and together ensure automated, accident-free operation. A critical aspect is that the stationary security must remain permeable for the loading vehicle, without this being able to be used intentionally or inadvertently by people to gain unnoticed access to the loading vehicle's path or the loading area. To this end, the invention defines a first position of the loading vehicle by placing it very close to the secured access area. A person in the first position will not fit between the loading vehicle and the secured access area. This is based on anthropometric measurements, whereby a body is typically larger than, for example, 20 cm, 30 cm, 50 cm, or 70 cm in the cross-sectional dimensions relevant here.The first position is initially defined in only one dimension to establish a distance from the secured access area. A second lateral dimension may be added in later embodiments.

[0014] When entering the loading area, the loading vehicle first drives to the first position. The first sensor then adjusts the access area security to create a passageway for the loading vehicle. In other words, in stationary security, partial muting occurs, allowing the loading vehicle to drive through the secured access area into the loading area. Because the first position is so close to the access area, no one can enter the passageway unnoticed.

[0015] The invention has the advantage of enabling automated loading and unloading that takes safety aspects into account. This eliminates the need to close off the entire operating area of ​​the loading vehicle to personnel, unlike previous approaches. This, along with shifting responsibility to the forklift driver, has been the traditional approach to preventing accidents. However, preventing personnel from accessing the vehicle altogether requires an expensive and complex infrastructure with numerous components and corresponding space requirements. Furthermore, this significantly limits the flexibility of logistical processes and is prone to failure. The invention does not have these disadvantages. Persons are permitted to remain in the vicinity and, for example, intervene in a timely manner in the event of impending disruptions or perform additional work steps. Thanks to the invention, accidents cannot occur.

[0016] The first sensor preferentially detects the presence of an object in the access area. Except in the exceptional situation of the loading vehicle in the passage corridor, the access area should be impermeable; in any case, objects should not enter undetected. The second sensor preferentially detects the presence of an object in front of the loading vehicle. This is intended to prevent collisions while the loading vehicle is moving; therefore, objects in the direction of travel are of particular interest. Objects in other directions can also be detected, for example to prevent accidents when the loading vehicle changes direction or to deal with situations such as a person jumping in front of the loading vehicle from the side. If the presence of an object is detected, a safety reaction of the loading vehicle is preferably initiated. If the mobile security system has detected an object, the potential hazard is obvious.An object detected by the stationary security system means that objects may be located in areas where the mobile security system is not prepared, particularly in the cargo area. Therefore, the stationary security system preferably also triggers a safety response when the presence of an object is detected in the access area. Depending on the safety concept, the loading vehicle can, for example, be stopped, perform an evasive maneuver, or decelerate to a safe slow speed of, for example, less than 0.3 m / s. The safety response can be accompanied or announced by a visual or acoustic warning signal.

[0017] The loading space is preferably a trailer or semi-trailer of a commercial vehicle or truck. Loading and / or unloading thus relates to the scenario explained in the introduction, with the access area preferably being located at a loading ramp. The loading vehicle, for example, travels back and forth between a logistics area and the trailer and semi-trailer. Preferably, the cargo is first prepared near the loading ramp and then loaded in two steps, with the loading process according to the invention then relating to the second step between the loading ramp and the loading space.

[0018] The loading vehicle preferably drives through the passage corridor to a second position, which is so close to the secured access area that no person can fit between the loading vehicle and the secured access area. The passage corridor is then closed, thus fully reactivating the security of the access area via the first sensor. In the second position, the access area is thus located behind the loading vehicle, again so close that it is impossible for a person to use the passage corridor unnoticed. If the passage corridor is closed again in the second position, a person inside it would be detected by the stationary security, and there would be insufficient space between the loading vehicle and the passage corridor for a person to slip through unnoticed into the loading area in time.After these steps, the loading vehicle is in the loading area, the access area is again impermeable, and it is ensured that only the loading vehicle has passed through the secured access area.

[0019] When exiting the loading area, the loading vehicle preferably first moves to the second position, and then the protection of the access area by the first sensor is adjusted such that a passageway is created for the loading vehicle. The loading vehicle then preferably moves through the passageway to the first position, and then the passageway is closed, thus fully reactivating the protection of the access area by the first sensor. The passageway is thus opened exclusively for the loading vehicle; at no time is there sufficient space for a person to use the passageway unnoticed. When exiting, the steps during entry are, to a certain extent, repeated with the roles of the first and second positions reversed. However, differences arise in the preferred activity of the mobile security, as explained below.

[0020] Preferably, a lateral position of the passage corridor is adapted to a lateral position of the loading vehicle. Thus, the position of the loading vehicle in the lateral direction in front of the access area is detected, and the passage corridor opens directly in front of the loading vehicle. In this embodiment, the first and second positions are defined only one-dimensionally as the distance to the access area; the second lateral spatial dimension, or transverse to the distance, is processed dynamically. Alternatively, the passage corridor can be created only at a fixed, now two-dimensionally defined first or second position, which the loading vehicle must then approach accordingly, taking the lateral position into account. Such a passage corridor can, in particular, be prepared as a predefined protective field configuration, to which the stationary protection is switched for and during the passage.It is also possible to provide several first and / or second positions that differ from each other in their lateral coordinates; this is a kind of intermediate step from fixed first and second positions to a completely dynamic consideration of the lateral position of the loading vehicle.

[0021] The securing of the loading vehicle with the second sensor is preferably inactive while moving within the loading space. The inventive procedure ensures that no person can have entered the loading space. Thus, the loading vehicle can operate within the loading space without regard to possible accidents involving moving objects or persons. This requires that no persons are initially present in the loading space when the stationary securing system is activated. However, checking this, for example, by the driver of a truck when preparing and opening a trailer, is a common requirement when commissioning a security application.

[0022] The protection of the loading vehicle with the second sensor is preferably deactivated from the first position at the earliest when entering the loading area and reactivated at the second position when exiting the loading area at the latest. From the first position when entering and up to the second position when exiting, the mobile protection is not required because the stationary protection ensures that no people cross the loading vehicle's path. Switching preferably takes place exactly at the first position when entering and exactly at the second position when exiting, so that the mobile protection does not operate unnecessarily redundantly to the stationary protection and, for example, an unnecessary safety reaction is not triggered by a loading object already in the entrance area of ​​the loading area.When exiting, the mobile security system must already be activated at the second position, as a person could be standing directly in front of the access area where the stationary security system has not yet detected them.

[0023] Preferably, the loading vehicle detects when it moves into a safety-relevant area in front of the access area and then activates the security with the second sensor at the latest. The area in front of the access area, in particular the area of ​​a loading ramp, is to be regarded as safety-relevant (confined). According to the invention, it is precisely not necessary to take additional measures to exclude the presence of people there, for example a driver of the truck or an employee who activates the stationary security for a loading / unloading process. For this reason, mobile security should be active. Further inside, for example in a logistics hall, where the cargo objects are fetched from or taken to, a restricted area for people can certainly be set up. Such areas are then not safety-relevant from the perspective of the loading vehicle, and mobile security can be dispensed with there.The detection of the safety-relevant area and the switching can be realized in particular by means of safety points according to the aforementioned DE 10 2019 128 782 A1.

[0024] The cross-section of the passage corridor preferably corresponds to the cross-section of the loading vehicle, at least except for a buffer area smaller than a person. The passage corridor is therefore just large enough for the loading vehicle to fit through and no person can enter the loading area unnoticed. A certain margin or buffer area is permissible to prevent even minor mishandling of the loading vehicle from being detected by the stationary security system. However, such a buffer area remains too small for a person, and the dimensions of a possible buffer area must be defined similarly to the distances between the first and second positions and the secured access area.

[0025] A stationary security system for the access area, equipped with the first sensor, and a mobile security system for the loading vehicle, equipped with the second sensor, are preferably connected to one another in a communication link. This allows the loading vehicle, in particular, to request the opening and closing of the access corridor and preferably to receive confirmation of this. Another possible application of the communication link, which is not exhaustive, is that the mobile security system can thus learn when the stationary security system has detected an object. In this case, it can no longer be guaranteed that the loading area is clear of people, and the loading vehicle must adapt its further activities accordingly; for example, it may only operate at a safe, slow speed or, if necessary, stop completely.Since safety-relevant information is exchanged between the stationary and mobile security systems, functionally secure communication must preferably be ensured, in particular through appropriate protocols.

[0026] The first sensor for securing the access area preferably monitors an upright, particularly vertical, protective field. The term protective field has a certain historical origin and can refer to a protective volume, i.e. a three-dimensional area. The upright protective field acts like a virtual wall that encloses the loading area, although this wall may have a certain inclination. The upright protective field is preferably monitored by more than one first sensor in order to realize different perspectives, for example by a first sensor on each side of the access area. Otherwise, a person in the shadow of the loading vehicle would remain undetected while it is passing through, so an additional first sensor from the opposite direction is preferably used. Alternatively, a sensor from a bird's eye view can be used; in this case, shadowing effects may be tolerable depending on the specific geometry.

[0027] The second sensor for protecting the loading vehicle preferably monitors a protective field, particularly a horizontal one in the direction of travel. Mobile protection is therefore based on protective field monitoring. The protective field extends at least in the direction of travel and is preferably oriented at least approximately parallel to the ground. Alternatively, there can be a fan of protective fields with different inclinations, in which case violations of the protective field caused by the ground are preferably detected and filtered out. The protective field or at least one additional protective field can protect at a wide angle to the front and also take into account lateral or even rear areas. Protective field protection of a vehicle is known per se, so a suitable protective field configuration and, for example, adaptation to the speed of the loading vehicle will not be discussed in detail.

[0028] The protective field of the second sensor is preferably successively shortened as the access area is approached. The protective field of the mobile protection device is designed so that if a person is detected, a timely reaction or braking can be carried out. From a certain point onwards to the first position when entering the loading area, such a protective field already extends into the area that the stationary protection device makes inaccessible anyway. This monitoring is redundant and can lead to unnecessary safety reactions, for example due to objects in the entrance area of ​​the loading area. This can be prevented by shortening the protective field of the mobile protection device, preferably just enough so that it ends at the access area. Switching the mobile protection device off in the first position is therefore preceded by a continuous transition with shortening of the protective field, whereby switching off can be understood as shortening to a length of zero.

[0029] The first sensor and / or the second sensor is preferably one of the following: a single-layer or multi-layer laser scanner, a LIDAR sensor, a 3D camera, in particular a time-of-flight camera, a radar, or a radio location system, the latter in particular an ultra-wideband system as described in the aforementioned EP 3 859 382 A1. When using a radio location system, the loading vehicle or persons are preferably equipped with a radio transponder.

[0030] Sensor options are available for both stationary and mobile protection, with different selections possible, for example, the access area can be protected with laser scanners and the loading vehicle with a camera or radar. The sensors are preferably safe sensors. As used throughout the description, safe and security mean that measures have been taken to control errors up to a specified safety level or to comply with the regulations of a relevant safety standard for machinery safety or electro-sensitive protective devices, some of which are mentioned in the introduction. "Not safe" is the opposite of "safe"; for non-safe devices, transmission paths, evaluation systems, and the like, the specified fail-safe requirements are therefore not met.

[0031] The loading vehicle is preferably securely located, at least in the first position and / or the second position. Optionally, the loading vehicle can be securely located at additional positions, up to and including the entire loading and unloading area. For this purpose, positions can be identified as safe points of interest within the meaning of DE 10 2019 128 782 A1, cited above.

[0032] The method is a computer-implemented method, at least with regard to the safeguards and preferably also with regard to an autonomous control of the charging vehicle, which runs, for example, in a computing unit of the mobile and / or stationary safeguards or of a higher-level system.

[0033] The inventive security system for loading and / or unloading a cargo space with a loading vehicle comprises a first sensor system for securing an access area of ​​the cargo space and a second sensor system for securing the loading vehicle. The two sensor systems can also be referred to as a stationary or mobile security system or as a stationary and mobile contactless protective device. The security system is designed to create a passage corridor for the loading vehicle in the first sensor system when the loading vehicle, upon entering the cargo space, has moved into a first position that is so close to the secured access area that no person can fit between the loading vehicle and the secured access area.It is not initially determined whether the corresponding control and evaluation functionality is to be assigned to the first sensor system, the second sensor system, and / or a higher-level system, whereby a communication connection preferably exists to distribute such roles. The safeguarding can be implemented according to one of the described embodiments of the method according to the invention.

[0034] The invention will be explained in more detail below with regard to further features and advantages, using exemplary embodiments and with reference to the accompanying drawings. The figures of the drawing show: Fig. 1 is a schematic overview of a security system with stationary security for an access area and mobile security for a loading vehicle; Fig. 2 is a schematic plan view of a loading area with potential hazards to persons posed by a loading vehicle; Fig. 3 is a schematic plan view of a loading area as an incoming loading vehicle approaches a secured access area; Fig. 4 is a schematic plan view of the loading area in which the incoming loading vehicle has reached a first position close to the secured access area; Fig. 5 is a schematic plan view of the loading area in which the incoming loading vehicle is located in a passage corridor through the secured access area;Fig. 6 is a schematic plan view of the loading area after the incoming loading vehicle has entered a second position close behind the secured access area and the drive-through corridor is closed again; Fig. 7 is a schematic plan view of the loading area in which the loading vehicle has again reached the second position close to the secured access area upon exiting the loading space; Fig. 8 is a schematic plan view of the loading area in which the outgoing loading vehicle is in the drive-through corridor through the secured access area; and Fig. 9 is a schematic plan view of the loading area in which the outgoing loading vehicle has again reached the first position outside and close to the secured access area and the drive-through corridor is closed again.

[0035] Figure 1shows a schematic overview of a security system for a loading / unloading process with a stationary security system 10 of an access area 12 and a mobile security system 14 of a loading vehicle 16. The loading vehicle 16 is preferably an autonomous vehicle, such as an AGV (Automated Guided Vehicle) or an AMR (Autonomous Mobile Robot) and is capable of picking up and putting down load objects and thus transporting them from one location to another.

[0036] The stationary security system 10 has at least one preferably secure sensor 18a-b, wherein, in the figures, two sensors 18a-b are used on each side of the access area 12 by way of example. The mobile security system 14 also has at least one preferably secure sensor 20, wherein, in the figures, only one sensor 20 is provided in the direction of travel by way of example, but at least one additional sensor can be added for redundant, rearward, and / or lateral monitoring.The sensors 18a-b and 20 operate according to a non-contact sensor principle, preferably according to an optical sensor principle such as a light grid, a laser scanner, a LIDAR sensor, a camera, or a 3D camera, in particular a time-of-flight camera, but also according to non-optical sensor principles such as a radar or radio location system, in particular an ultra-wideband system, as described in the aforementioned EP 3 859 382 A1. The sensors 18a-b and 20 can be selected as desired from the aforementioned and other non-contact sensors, although some sensors are not equally suitable for both protection systems 10, 14, for example, a light grid only for the stationary protection system 10. The invention is described below using laser scanners as an example.The object detection is based on a protective field concept, which is also exemplary, since it only matters to safely detect objects in the access area 12 or in the respective travel path of the loading vehicle 16.

[0037] A control and evaluation unit 22, 24 is provided in each of the stationary protection system 10 and the mobile protection system 14. The control and evaluation functionality, using the method described below, can be distributed virtually arbitrarily between the two control and evaluation units 22, 24 and also at least one external control and evaluation unit of a higher-level system. Preferably, however, at least the respective object detection or protective field evaluation takes place close to or in the associated sensor 18a-b, 20.

[0038] Any computing units can be considered as the hardware of the control and evaluation units 22, 24, such as digital computing components such as a microprocessor or a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor), an ASIC (Application-Specific Integrated Circuit), a K1 processor, an NPU (Neural Processing Unit), a GPU (Graphics Processing Unit), or the like. An external computing unit can be a computer of any type, including notebooks, smartphones, tablets, a (safety) controller, a local network, an edge device, or a cloud. Safety-relevant parts of the control and evaluation systems are preferably implemented in secure hardware or achieve a required level of security through other measures such as redundancy or testing.

[0039] Furthermore, a communication interface 26, 28 is provided in each of the stationary security system 10 and the mobile security system 14. Via these interfaces, the stationary security system 10 and the mobile security system 14 are preferably wirelessly connected to each other to exchange data, information, and control signals. The communication connections can be implemented using any protocol, such as Bluetooth, WLAN, Wi-Fi, 3G / 4G / 5G, and in principle any other protocol.

[0040] The stationary protection system 10 implements the access protection safety function. It detects when an object is located in the access area 12, and in particular when a person attempts to pass through. It is possible to keep certain parts of the protected access area 12 clear, thus creating a passageway in which the safety function is bypassed or muted. This can also be achieved by switching to a protective field with a clear area.

[0041] The mobile safety system 14 implements the collision avoidance safety function of the loading vehicle 16. This ensures that safety distances are maintained and that objects or persons do not come into direct contact with the loading vehicle 16, or at most only come into inconsequential contact at the minimum, safe speed of the loading vehicle 16.

[0042] If an unauthorized object is detected in the access area 12 or in front of the loading vehicle 16, this triggers a safety reaction of the loading vehicle 16 to prevent hazards to persons. The mobile protection system 14 reacts to an object in front of the loading vehicle 16 in a safety-oriented manner as part of its own collision avoidance. A safety-relevant situation due to an object in the access area 12 is reported to the mobile protection system 14 via the communication interfaces 26, 28 by the stationary protection system 10. As a respective safety reaction, the loading vehicle 16 is stopped, executes an evasive maneuver, or reduces its speed such that a collision with a person becomes extremely unlikely and, in any case, cannot seriously endanger their health.The safety response may differ depending on whether it is triggered by collision avoidance or access control.

[0043] With the mobile security system 14 and / or other sensors not shown, a secure localization system for the loading vehicle 16 is preferably also implemented. For this purpose, a map can additionally be stored in the control and evaluation unit 24. It is also possible to attach optical or physical markers in the vicinity of the loading / unloading zone. With the localization system, the loading vehicle 16 recognizes, in particular, that it is located in a security-relevant area and no longer, for example, in a cordoned-off logistics area inaccessible to persons, so that the mobile security system 14 must be activated. Furthermore, it can be used to recognize certain relevant positions (to be described later) during loading / unloading. To implement the method according to the invention, a few positions are sufficient, which can, for example, be security points according to DE 10 2019 128 782 A1 mentioned in the introduction.

[0044] Figure 1shows a stationary security system 10 in a 1:1 relationship to a mobile security system 14. This is an exemplary simplification. One or more stationary security systems 10 can cooperate with one or more mobile security systems 14, or corresponding connections can be established or terminated depending on the location and task of the loading vehicle 16.

[0045] Figure 2shows a schematic top view of a loading area or loading / unloading zone. The loading area comprises a loading ramp 30 and a loading space 32, of which only the front part is shown. The loading ramp 30 forms a safety-relevant area ("confined zone") because people may be present there. Therefore, to avoid potential danger to people, the loading vehicle 16 must activate its mobile safety system 14, which is shown here for simplified purposes and representatively only with a laser scanner as sensor 20. Figure 2shows some possible hazards posed by a person 34a on the loading ramp, a person 34b in the loading space 32, or a person 34c-d located to the side, whose arm in particular could be crushed. The mobile safety system 14 is capable of detecting all of these persons 34a-d in a timely manner and initiating an appropriate safety response. The problem is that, particularly within the loading space 32, due to the densely packed and unknown load objects, it is practically impossible to determine whether a person 34b is present there. The loading vehicle 16 must initiate its safety response as a precaution and is thus virtually unavailable. On the other hand, the mobile safety system 14 cannot simply be deactivated because then the safety of persons 34a-d in the positions shown and in other positions would not be guaranteed.

[0046] With reference to the Figures 3 to 9The method according to the invention for loading and unloading the loading space 32 will now be explained. Not all of the described steps of the particularly preferred overall concept necessarily have to be carried out. For example, the loading space 32 is the trailer of a truck. However, the invention can also be used for a different loading space 32 with a different front area than the loading ramp 30.

[0047] Figure 3shows a schematic plan view of the loading area with loading ramp 30 and loading space 32 as an incoming loading vehicle 16 approaches. The loading space 32 is closed on all sides with the exception of the access area 12, via which the loading space 32 can be accessed from the loading ramp 30. The stationary security system 10 monitors the access area 12 so that no object or person can enter the loading space 32 unnoticed. For the sake of simplicity and representativeness, only two laser scanners arranged opposite one another as sensors 18a-b are shown here; the mobile security system 14 of the loading vehicle 16 is still represented by the sensor 20, which monitors a protective field 36 in the direction of travel.

[0048] At the start of a loading / unloading process, the semi-trailer with the loading space 32 is docked at the loading ramp, and the truck driver or a logistics employee opens the semi-trailer, thus making the loading space 32 accessible via the access area 12. This is followed by a manual check to ensure that no one is in the loading space 32, by checking, calling, or the like. The stationary safety system 10 is then activated, for example, via a button. Such a manual release or (re)start process for commissioning is common for safety-related applications. After activation, the stationary safety system ensures that no access is permitted and that the loading space 32 remains clear of persons.

[0049] When the loading vehicle 16 approaches the loading ramp 30, it detects, preferably by means of its secure localization system, that it is now in a safety-relevant area and then activates its mobile security system 14 or the protective field 36. Alternatively, the protective field 36 can always be active while the loading vehicle 16 is traveling, with the exception of the movements in the loading area 32 explained below. The loading vehicle 16 or its mobile security system 14 establishes a communication connection to the stationary security system 10. It queries whether the access protection is operational, i.e. whether no access has yet been made and therefore no person can be in the loading area 32. As the loading vehicle 16 approaches the secured access area 12, the protective field 36 can be successively shortened, as indicated by the arrow 38.Monitoring into the loading space 32 is not necessary because the stationary security system 10 prevents access, so that a protective field 36 projecting into the loading space 32 cannot detect a person anyway, but a false triggering of the safety reaction by an object in the loading space 32 is very possible.

[0050] Figure 4shows a schematic plan view of the loading area in which the entering loading vehicle 16 has reached a first position close to the secured access area 12. In the first position, the distance d between the loading vehicle 16 and the secured access area 12 is no longer sufficient for a person 34, indicated by shade, to fit between them. For example, the distance d is 20 cm or even less, but even with a somewhat larger distance d such as 30 cm, 50 cm, or 70 cm, a person will not be able to push themselves between the loading vehicle 16 and the secured access area 12 without being noticed by the stationary security system 10. The loading vehicle 16 detects the reaching of the first position, in particular with its secure localization system.

[0051] In the first position, the mobile protection system 14 requests the release of a passage corridor from the stationary protection system. A corresponding section of the secured access area 12 should therefore be muted or switched to a protective field configuration that leaves the passage corridor clear. If necessary, because the passage corridor cannot be established quickly enough, the loading vehicle 16 stops temporarily. From now on, the mobile protection system 14 is preferably deactivated, since no person can be in front of the loading vehicle 16 and thus in the loading area 32 behind the secured access area 12 anyway.

[0052] Figure 5shows a schematic plan view of the loading area in which the entering loading vehicle 16 is located in the released or muted passage corridor 40 of the secured access area 12. Laterally, i.e. in a dimension transverse to the direction of travel, the position of the passage corridor 40 is either dynamically adapted to the lateral position of the loading vehicle 16, or the loading vehicle 16 is moved into a first position with a fixed lateral position, so that the lateral position of a fixed passage corridor 40 matches the lateral position of the loading vehicle 16. In the figures, the direction of travel during entry is from left to right, for example, so that the lateral position in the illustration corresponds to the vertical position. During the passage, a signal exchange preferably takes place between the mobile security system 14 and the stationary security system 10 in order to keep the passage corridor 40 open.

[0053] Figure 6 shows a schematic plan view of the loading area after the incoming loading vehicle 16 has entered a second position close behind the secured access area 12. In the second position, analogous to the first position, there is too little space between the loading vehicle 16, now its rear end, and the secured access area 12 for a person 34 to fit inside. The drive-through corridor 40 is now closed again after the mobile security system 14 has detected arrival at the second position and has reported to the stationary security system 10 that muting is no longer required. The secured access area 12 is thus no longer permeable. The loading vehicle 16 can now move freely in the loading space 32 with the mobile security system 14 still inactive and move cargo objects there, in particular deposit its brought-along load there or pick up a new load.

[0054] Figure 7 shows a schematic plan view of the loading area, in which the loading vehicle 16 wishes to leave the loading space 32 after completing its work and, upon exiting the loading space 32, has again reached the second position close to the secured access area 12. Since this is the return journey, the front end of the loading vehicle 16 is again decisive here. Incidentally, the loading vehicle 16 can also reverse instead of turning in the loading space 32; in this case, the rear end of the loading vehicle 16 is still decisive, and the mobile safety system 14 must secure the reversing journey, which is not further differentiated here.

[0055] Analogous to the entry at the first position, the mobile protection system 14 requests the release of the through corridor 40 from the stationary protection system 10 upon exit at the second position, and the loading vehicle 16 is stopped, if necessary, until confirmation of the establishment of the through corridor 40 has been received. The mobile protection system 14 now reactivates its collision protection or the protective field 36 at the latest, since a person 34 may be standing in front of the secured access area 12. Activation can also occur somewhat earlier, depending on the speed at which the loading vehicle 16 is moving. If, for example, it is scheduled to stop in the second position first to establish the through corridor 40, earlier activation is unnecessary.

[0056] Figure 8shows a schematic plan view of the loading area, in which the departing loading vehicle 16 is located in the passage corridor 40 through the secured access area 12. Again, during the passage, a signal exchange preferably takes place between the mobile security system 14 and the stationary security system 10 in order to keep the passage corridor 40 open during the passage.

[0057] Figure 9shows a schematic plan view of the loading area, in which the departing loading vehicle 16, after passing through, has reached the first position outside the loading space 32 and close to the secured access area 12. The mobile security system 14 signals to the stationary security system 10 that the access area 12 can be closed again. As soon as this has happened, the stationary security system 10 alone ensures that no persons enter the loading space 32 unnoticed. The loading vehicle 16 can move further along the loading ramp 30 under the sole responsibility of its mobile security system 14 and, for example, pick up the next load or deposit a load brought from the loading space 32 at a designated location, for example at the edge of the loading ramp 30 or in a logistics hall.

[0058] As long as the passage corridor 40 is open, and this applies to the exit as well as to the entry, the loading vehicle 16 physically prevents an unnoticed intrusion of a person due to the dimensions of the passage corridor 40 adapted to the loading vehicle 16 and the first position and second position located close to the secured access area 12, which would inevitably be noticed by the non-muted part of the secured access area 12.

[0059] If at any time the stationary security system 10 detects an object in the secured access area 12, the loading vehicle 16 may no longer enter the loading area 32 until the stationary security system 10 is cleared again, which generally requires a manual inspection of the loading area 32. Under certain circumstances, the stationary security system 10 can still differentiate a direction of movement and tolerate an object that partially moves in and then back out again. An object that only moves out indicates that the initial clearance was faulty; this must not occur, and a fundamental inventory should be conducted if necessary.If the loading vehicle 16 is already in the loading space 32 when the secured access area is violated, the loading vehicle 16 must stop or leave the loading space 32 at a very slow safe speed or with the collision avoidance function active.

Claims

1. A method for loading and / or unloading a loading space (32), in particular the loading space (32) of a transport vehicle, using a loading vehicle (16) which drives at least once into the loading space (32) in order to deposit and / or pick up at least one load object, an access area (12) of the loading space (32) being protected in a stationary protection by at least one first sensor (18a-b) that detects the presence of an object in the access area (12), and the loading vehicle (16) being protected in a mobile protection by at least one second sensor (20) that detects the presence of an object in front of the loading vehicle (16) and thus stationary and mobile protection jointly ensure that the loading vehicle (16) does not collide with unexpected objects during loading and / or unloading, characterized in that, when entering the loading space (32), the loading vehicle (16) first moves into a first position which is so close to the protected access area (12) that no person (34) can fit between the loading vehicle (16) and the protected access area (12), and then the protection of the access area (12) by the first sensor (18a-b) is adapted in such a way that a passage corridor (40) is created for the loading vehicle (16), thus partial muting takes place in the stationary protection, which enables the loading vehicle (16) to drive through the protected access area (12) into the loading space (32).

2. The method according to claim 1, wherein a safety reaction of the loading vehicle (16) is initiated when the presence of an object is detected.

3. The method according to claim 1 or 2, wherein the loading space (32) is a trailer or semitrailer of a commercial vehicle or truck and / or the access area (12) is arranged at a loading ramp (30).

4. The method according to any of the preceding claims, wherein the loading vehicle (16) drives through the passage corridor (40) to a second position which is so close to the protected access area (12) that no person (34) fits between the loading vehicle (16) and the protected access area (12), and then the passage corridor (40) is closed and thus the protection of the access area (12) by the first sensor (18a-b) is fully reactivated.

5. The method according to any of the preceding claims, wherein the loading vehicle (16) initially moves into the second position when leaving the loading space (32) and then the protection of the access area (12) by the first sensor (18a-b) is adapted such that a passage corridor (40) is created for the loading vehicle (32) and wherein in particular the loading vehicle (16) moves through the passage corridor (40) into the first position and then the passage corridor (40) is closed and thus the protection of the access area (12) by the first sensor (18a-b) is fully activated again.

6. The method according to any of the preceding claims, wherein a lateral position of the passage corridor (40) is adapted to a lateral position of the loading vehicle (16).

7. The method according to any of the preceding claims, wherein the protection of the loading vehicle (16) with the second sensor (20) is inactive during the movement in the loading space (32), wherein in particular the protection of the loading vehicle (16) with the second sensor (20) is switched to inactive at the earliest from the first position when entering the loading space (32) and is switched to active again at the latest up to the second position when leaving the loading space (32).

8. The method according to any of the preceding claims, wherein the loading vehicle (16) recognizes when it moves into a safety-relevant area (30) in front of the access area (12) and at the latest then switches the protection with the second sensor (20) to active.

9. The method according to any of the preceding claims, wherein the cross-section of the passage corridor (40) corresponds to the cross-section of the loading vehicle (16) at least except for a buffer area smaller than a person (34).

10. The method according to any of the preceding claims, wherein a stationary safeguarding system (10) of the access area (12) including the first sensor (18a-b) and a mobile safeguarding system (14) of the loading vehicle (16) including the second sensor (20) are in communication connection (26, 28) with each other, in particular so that the loading vehicle (16) requests an opening and closing of the passage corridor (40) and / or in order to inform the loading vehicle (16) of the presence of an object in the access area (12).

11. The method according to any of the preceding claims, wherein the first sensor (18a-b) monitors an upright, in particular vertical, protective field to protect the access area (12) and / or the second sensor (20) monitors an in particular horizontal protective field (36) in the direction of travel to protect the loading vehicle (16).

12. The method according to claim 11, wherein the protective field (36) of the second sensor is successively shortened as the access area (12) is approached.

13. The method according to any of the preceding claims, wherein the first sensor (18a-b) and / or the second sensor (20) is one of the following: a single-layer or multi-layer laser scanner, a LIDAR sensor, a 3D camera, in particular a time-of-flight camera, a radar or a radiolocation system.

14. The method according to any of the preceding claims, wherein the loading vehicle (16) is reliably localized, at least in the first position and / or the second position.

15. A safety system (10, 14) for loading and / or unloading a loading space (32) with a loading vehicle (16), wherein the safety system (10, 14) comprises a stationary sensor system (10) for protecting an access area (12) of the loading space (32) using a first sensor (18a-b) for detecting the presence of an object in the access area (12) and a mobile sensor system (14) for protecting the loading vehicle (16) with a second sensor (20) for detecting the presence of an object in front of the loading vehicle (16), and thus the stationary sensor system (10) and the mobile sensor system (14) jointly ensure that the loading vehicle (16) does not collide with unexpected objects during loading and / or unloading, characterized in that the safety system (10, 14) is configured to create a passage corridor (40) for the loading vehicle (16) in the stationary sensor system (10) when the loading vehicle (16) has moved into a first position when entering the loading space (32), so that partial muting takes place in the stationary sensor system (10), which enables the loading vehicle (16) to drive through the protected access area (12) into the loading space (32), the first position being so close to the protected access area (12) that no person (34) can fit between the loading vehicle (16) and the protected access area (12).