Barrier device, and assembly in a through-access area

Abstract

The invention relates to a barrier system comprising a blocking means, wherein, using one or more LIDAR sensors and a computer unit, the position, movement direction and speed of objects, including people, are detected and calculated, and comprising a control unit which automatically prompts a change in position of the blocking means between the release position and blocking position thereof according to the determined object movement.

Description

[0001] The invention relates to a barrier device according to the features in the preamble of claim 1 and an arrangement in a passageway according to the features in the preamble of claim 16.

[0002] Entrances and exits of publicly accessible buildings or similar structures, hereinafter collectively referred to as passageways, generally feature barrier devices to allow regulated entry and exit. These barrier devices are arranged within a passageway that may extend in front of and behind the barrier device and in which persons or objects, hereinafter collectively referred to as objects, may be located. Furthermore, barrier devices include adjustable locking mechanisms such as doors, barrier bars, gates, or the like. Before entering retail premises, such as supermarkets, kiosks, drugstores, etc.,In order for people to enter buildings such as hotels, office buildings, or similar structures, access must be granted by moving the locking device from a closed position to a release position, thus enabling objects to pass through the barrier in the direction of passage. If the passage is an entrance, the direction of passage is for entering, whereas in the case of an exit, the direction of passage is for leaving.

[0003] As a result of their steadily increasing prevalence, automated barrier devices will become increasingly important, especially for so-called self-check-out facilities, which are regularly operated without staff.

[0004] Automated barrier devices with detection units, comprising signal transmitters and receivers, are well-known in practice. Laser scanners are particularly common as signal transmitters, emitting numerous parallel, plane-aligned laser pulses into a scanning environment for object detection. The boundaries within which the laser scanner scans the environment define a so-called detection field. The laser beams are reflected by objects located within the detection field and detected by a signal receiver. By determining the travel time of the individual reflected laser beams, the position of an object within the detection field can be ascertained.

[0005] From EP 2 332 805 A1, a sensor arrangement is known with a laser scanner positioned at a distance from a barrier. The starting point for controlling a barrier device is several zones, which are delimited within a scanning area. As soon as an object is detected in a specific zone, the barrier device is adjusted accordingly.

[0006] All known barrier devices share the problem of highly imprecise control. In practice, this manifests itself, for example, in barriers being opened unnecessarily. Unnecessarily opening doors, for instance, can lead to heat loss in winter or heat gain in summer. Furthermore, airlocks with at least two doors, barriers, or similar devices connected in series in the direction of passage are known from practical experience in order to compensate for the imprecise control of the known devices. However, such airlock systems significantly increase the required space and technical complexity.

[0007] US Patent 2005 / 0224700A1 discloses a device for the automatic operation of a door, in particular a vertical door, such as those known in practice as high-speed doors. This device can have more than one signal transmitter by having more than one detection device in order to create multiple detection fields and, for example, to cover the respective access areas to a passageway in the wall on both sides.

[0008] From DE 10 2020 106 825 A1, a control system for access control systems is known that enables demand-based operation of an access control system. From a previously determined set of demand parameters, at least one dynamic setpoint value is calculated for controlling the access control system, and a swing arm element of the access control system is controlled with this dynamic setpoint value, thus ensuring continuous demand-based operation of the access control system.

[0009] US patent 2012 / 0274466 A1 discloses an anti-theft device that incorporates a laser scanner whose detection range defines a monitoring plane. The laser scanner is positioned and oriented such that its monitoring plane detects the crossing of a barrier—for example, a sales counter or checkout area—and subsequently triggers a theft alarm. Furthermore, the anti-theft device includes an authorization mechanism for activating or deactivating the laser scanner.

[0010] The present invention aims to improve known devices, particularly by preventing malfunctions so that passage is only granted when necessary. Furthermore, an economically advantageous solution is to be proposed, especially minimizing the equipment required. This objective is achieved by a barrier device according to the features of claim 1 and by an arrangement of a barrier device according to claim 16. Advantageous embodiments are described in the dependent claims.

[0011] In other words, the invention proposes a barrier device that is controlled independently of the detection area. By calculating the direction or speed of an object, its movement can be predicted in the form of a trajectory within the passageway. Essentially, a distinction is made between whether an object is approaching a barrier or not, allowing for a precise determination of whether and when passage should be opened, thus preventing malfunctions of the barrier device. This is based on a dynamic determination of the object's position within the passageway, as opposed to a low-resolution, static position determination using zone delimitation within the detection area.

[0012] As proposed, the detection field covers at least the area of ​​the passageway which is in front of a barrier - i.e., in the direction of passage, the area of ​​the passageway in which the objects are located before passing the barrier.

[0013] The invention is based on the idea that, directly from the calculated information regarding the direction and speed of movement, derived from the travel times of the laser beams, a distinction can be made between an object approaching the barrier and one at rest. The control unit only initiates a change to the release position when an object is approaching the barrier. Furthermore, the approach of an object only results in the passage being released if, for example, the calculated direction of approach allows the conclusion that the object is actually moving towards the barrier. For objects that merely move past a barrier without appearing to intend to pass through it, the control unit does not initiate a change in the position of the locking mechanism.

[0014] Particularly advantageous in terms of very high spatial resolution is the ability of the computing unit to derive the object movement in real time or near real time, thus increasing the precision of the control and avoiding collisions of objects with a barrier.

[0015] As proposed, the detection field is oriented essentially parallel to the horizontal plane, preferably at an angle between 0 and 10°, and particularly preferably at an angle between 0 and 3°. Furthermore, only one detection plane is provided for the detection field, thus significantly simplifying the design of the detection device in an economically advantageous way.

[0016] According to the invention, the precision of the motion data is further increased by the fact that the barrier device has several signal transmitters that essentially cover the passageway. In particular, the arrangement of multiple signal transmitters would also allow for the detection of areas that, when using only one signal transmitter, would be detectable in the detection shadow, i.e., on the side of an object facing away from the signal transmitter. Such shadows, i.e., areas lying outside the detection field, can be particularly problematic with objects placed in the passageway, thus preventing unimpeded object detection by the detection device. As long as a second object located behind the first does not extend beyond the detection shadow of the first object into the detection field, the second object would not be detected.Advantageously, to prevent shadowing, a first signal transmitter can be placed in, on or adjacent to the barrier and a second signal transmitter at a distance from it.

[0017] Furthermore, according to the invention, multiple travel times are determined for each object, thus allowing the derivation of multiple pieces of information regarding the direction and speed of movement. A fundamental problem arises here, however, that peripheral body parts of people, such as arms swinging while walking, significantly increase the variance of an object's motion data. To refine the derived object motion, the processing unit can advantageously be designed for computational refinement. In other words, the processing unit can derive from the object's motion data which of the determined motion data represent the core of the object, so that, for example, arms swinging while walking are recognized as such, and the processing unit preferably uses the motion data of the object's core to calculate the direction and speed of movement.This concretization of the derived object movement could lead to a significant refinement and thus more precise control of the barrier device.

[0018] Finally, the invention also provides that the multiple time-of-flights determined by several detection devices designed as LiDAR sensors result in a multiple of individual points of the same object, designated as point curves, and that the processing unit is configured in such a way that this point curve is represented in a polar coordinate system and is subsequently automatically transformed into a Cartesian coordinate system, taking into account the Cartesian position of each individual LiDAR sensor. The point curves of the multiple LiDAR sensors are then automatically converted into a common Cartesian coordinate system, and the probable position of the object is then automatically calculated from the multiple point curves that represent the same object in the common coordinate system.

[0019] The signal transmitter can be positioned in, on, or adjacent to the barrier. The smaller the distance between the object and the signal transmitter, especially between the object and a laser scanner, the more precise the time-of-flight measurement. Such an arrangement would therefore contribute to increasing the precision of the determined object movement, since objects intending to cross the barrier generally move towards the barrier and, consequently, towards the signal transmitter.

[0020] Particularly for barriers such as gates, barrier bars, or similar devices, the signal transmitter can be positioned at the same height as the barrier. This would ensure that the control unit preferably releases the passage for objects whose height closely corresponds to the barrier's mounting height relative to the ground surface supporting the objects. False triggers, for example, those caused by small animals, could be avoided. Reducing unnecessary false triggers of the barrier device generally results in an economically advantageous extension of its service life. Initial tests have shown a mounting height between 20 and 80 cm to be advantageous.

[0021] With multiple signal transmitters, the respective detection fields of the transmitters can be aligned parallel to each other and offset vertically. This would allow for the targeted detection of objects of different sizes, especially different heights, and minimize shadowing areas.

[0022] In a particularly advantageous embodiment, the signal transmitter can be mounted for rotation about a substantially vertically oriented axis of rotation and configured to detect at least a portion of a circular detection field around the transmitter. A correspondingly rotating signal transmitter could emit at least 10 laser pulses per second to create the most realistic possible representation of the objects. Initial tests have shown that a detection radius of up to 5 m is particularly suitable for deriving sufficiently high precision in object movement, even at a distance from the signal transmitter.

[0023] An economically advantageous arrangement of a rotating signal transmitter can be, for example, in or on a support of a barrier, where the support pivots to hold a locking bar, barrier, or similar device, thus enabling the detection field to extend from in front of to behind the barrier in the direction of passage, even if the barrier device only has one signal transmitter. In this way, a large detection field could be achieved with minimal equipment.

[0024] The invention is based on the consideration of both quantitatively detecting object movement and recognizing a stationary, motionless object, and initiating control of the barrier device with respect to the stationary object. If the direction and speed of movement of an object are essentially zero for a period of time, the object could be recognized as temporarily stationary. Control can consist, on the one hand, of initially withholding passage for a stationary object. On the other hand, in one embodiment, the control can nevertheless trigger passage for a stationary object in exceptional cases, namely when the object remains at a certain distance from the barrier for a specific period of time. This area is referred to here as the trigger area.Initial tests have shown that an area with a distance of up to 50 cm in the direction of passage in front of and behind the barrier and a dwell time of at least 5 s are particularly suitable.

[0025] Particularly for horizontally movable locking devices with multiple locking device segments, such as a sliding door consisting of several doors or door segments, or the like, which are held by a wall like a retaining element, the opening width can advantageously be adapted to the object's movement. For a further embodiment, it can therefore be provided that the object's movement is first precisely determined in order to derive which locking device segment needs to be controlled sufficiently to allow passage for the object. In practice, for example, only the door segment towards which the object is moving could be opened by the control unit, or the sliding door could only be opened up to a certain door segment, so that separate control of a locking device or a locking device segment would not yet be necessary.Advantageously, with this design of the barrier device, the opening width of the passage for release could be significantly reduced, so that, for example, energy loss due to escaping heat from a shop in winter would be minimized.

[0026] Separate control of multiple barrier devices or barrier segments can be provided, for example, to allow passage for several objects simultaneously. In practice, the barrier device could, for instance, have two separately controllable, pivoting barrier bars, as are found in many shops, which the control unit could open and close independently of each other, depending on how closely an object approaches the individual barrier bars.

[0027] Furthermore, the switching speed from a closed locking position to an open release position can be advantageously adjusted to the movement speed of an object, for example, the horizontally oriented swinging motion of a swing door or the retraction of a sliding door, or a vertically opening barrier or gate. Generally, a slower opening of a locking device, especially with heavy locking devices such as glass doors, is advantageous in order to protect drive units and braking systems and to extend their service life in an economically advantageous way.

[0028] A locking device can pose a hazard to an object in the passageway, insofar as the object, particularly during a change of position from a released to a locked position, can collide with the movable locking device. This section of the passageway is referred to here as the collision zone. Advantageously, the control unit is designed to take into account the current position of an object in the collision zone, as well as its expected position derived from the direction and speed of movement, when controlling the locking device, in order to prevent a collision. It can be provided that a movement of a locking device or...In the event of a collision risk, the movement of a segment of a barrier device may be prevented, and / or the movement of the barrier device may be accelerated, and / or the characteristics of the barrier device's movement, such as the opening width of a door, the swing height of a barrier, or similar, may be adjusted to avoid a collision. For example, if a shopping cart is placed in the collision zone of a barrier device, it may be ensured that, in the case of another approaching object, the passage is only opened to the extent that the barrier device does not collide with the shopping cart.

[0029] For customer management purposes, a further design option could include a counting unit in the barrier device. This unit uses object movement data to determine the number of objects that have passed through the barrier. This allows for a simple and cost-effective way to track, for example, how many objects have used a passage within a given time period. Furthermore, it is advantageous to determine, ideally in real time, how many objects are present in a store or similar location at any given time. This could be achieved, for instance, with a system of multiple interconnected barrier devices, each positioned at an entrance or exit.To minimize the required installation space and thus be economically advantageous, a barrier device can be used that serves as both an entrance and an exit, tracking the number of objects in the store, particularly in relation to the direction of movement of the objects as they pass through the barrier, since each direction of passage can be assigned to entering or exiting the store. If a capacity limit regarding the maximum number of objects in a store, building, or similar structure is reached, the control unit, in feedback with the counting unit, can only release the barrier again after a corresponding number of objects have left the store. Tracking the number of objects in a store is a common practice, for example, using shopping baskets or carts issued to customers.If all baskets or shopping carts are in use, this can signal that a capacity limit has been reached. However, this requires that every customer, i.e., every item, must carry either a shopping basket or a shopping cart, which, especially during pandemic times, necessitated additional staff and is therefore economically disadvantageous.

[0030] For a barrier system, it can be designed to detect objects crossing it in the opposite direction to the flow of traffic. For example, the passageway could be an entrance, and the detection field could cover areas of the passageway located in front of and behind the barrier in the direction of entry. More generally, the detection field could cover areas of the passageway located in front of and behind the barrier in the direction of traffic. If such object movement is detected, an alarm device can advantageously be provided that generates a visual and / or audible signal, for example, if a customer leaves a store or similar establishment without having passed through a checkout area. It can also be provided that the control unit prevents the passageway from opening if such object movement is detected.This design is particularly advantageous because it eliminates the need for structurally complex double barrier devices in the form of a lock.

[0031] In accordance with the considerations underlying the invention, a method for opening a passage in a passageway in which objects move at least intermittently may, in particular, comprise the following steps: A laser scanner emits laser pulses that generate a plane-like detection field, which is essentially parallel to the horizontal plane and at least partially aligned with the passageway. The travel time of the laser beams is determined after they have been reflected by objects located in the passageway. From the travel time, an object movement is calculated, specifically a direction and speed of movement of the objects in the passageway. Depending on the calculated object movement, the barrier is controlled in such a way that the passageway is opened, possibly individually adapted to a specific object, or blocked.

[0032] A barrier device or arrangement as described above can advantageously be implemented using one or more combined LIDAR sensors (= abbreviation for Light detection and ranging or Light imaging, detection and ranging) for the detection of objects, including moving objects such as people.

[0033] Access and egress control is achieved either without barriers or by movable barriers that must not collide with objects or persons during their movement. As an example of physically implemented, movable barriers, pivoting barriers are mentioned below. These are horizontally pivoting and are widely known from shopping centers; they must not collide with objects or persons when pivoting. A barrier-free barrier device can, for example, have an imaginary line as a barrier in accordance with the present invention, and the holding device in this case is the device in which the imaginary line is defined. This can be the automated control unit connected to the computing unit of the barrier device, so that, for example, a certain distance from the detection device, known as the boundary distance, defines a virtual line.Different boundary distances can be defined for different angles at which the light rays are emitted or detected by the detection device, so that the line path does not necessarily have to run in a circular arc around the detection device at a constant distance, but can also deviate from this, e.g., be defined as a straight line. For example, a barrier-free device can be arranged in the exit area of ​​a market, downstream of the cash registers, so that the barrier device according to the invention serves as an exit control.

[0034] When using the barrier device as an exit control, for example, a customer's dwell time at the checkout can be recorded. If this dwell time falls below a certain minimum and the customer subsequently crosses the imaginary line, an alarm can be automatically triggered. In this way, the imaginary line acts as a barrier to prevent people from leaving the store without paying. Such an exit control system can be installed using a barrier device according to the invention, particularly in self-checkout or scanner checkouts where customers register their purchases electronically—e.g., using barcodes, RFID tags, or the like. The automated control unit can be connected not only to the processing unit of the barrier device but also to the self-checkout or scanner checkouts themselves, such that—for example—Regardless of or in addition to the length of stay at the checkout, the alarm is automatically triggered if no payment transaction has been carried out at a particular checkout and the person initially at the checkout then moves towards the blocking device, namely the aforementioned imaginary line.

[0035] A change in position between the release and blocking positions of a barrier device, which is automatically initiated by the control unit, can be achieved, for example, by a horizontal pivoting movement of the physical barrier. In the case of a physical barrier, the change in position can be achieved, for example, by switching a switching element, such as to trigger or suppress an alarm. During entry and exit, objects must be detected with regard to their position, distance, and speed of movement. In this context, "objects" refers to both inanimate and living entities, particularly people.

[0036] When movement occurs in a predefined permissible direction, a physical locking device should open the barrier, e.g., swing a barrier into a release or open position, provided the space behind the barrier is clear in the direction of swing. However, if an object is located within the locking device's range of motion, the device's movement can be restricted: the locking device may move over a reduced portion of its range to avoid a collision with the object. Alternatively, the movement may be slowed—at least when approaching the object—to prevent damage or injury. Finally, the movement may be completely suppressed. With a barrier system without a fixed barrier, no alarm is triggered when movement is detected in a predefined permissible direction.

[0037] Unlike the movement described above, which occurs in a predefined direction as permissible, the barrier can remain closed during movement in a direction defined as impermissible. For example, the barrier can remain in a locked or closed position. This can be used for so-called "opposite-passers," meaning people who do not enter a store through the entrance but instead exit through the entrance, bypassing the checkouts. The barrier device serves as an access control system in this case. If the barrier is not already closed and remains in its closed position, the barrier's control system can be configured to move the currently open barrier into its closed position. In a barrier-free access control system, an alarm can be triggered in this situation.The barrier device can have one, two or more locking devices, and the barriers can be arranged side by side, e.g. opposite each other and working synchronously in opposite directions in the form of a double barrier to allow for a large opening width.

[0038] Alternatively or additionally, the barriers can be arranged one behind the other, as a "gateway" with alternating release of the individual barriers.

[0039] The barriers can be interconnected via a radio system, therefore they can cooperate logically (via software) instead of physically (via cable).

[0040] If the LIDAR sensors monitor an overlapping area, their readings can be "combined" by software. This offers the advantage of eliminating shadows cast by objects located one behind the other, as monitoring is performed from different angles.

[0041] The LiDAR sensors can be mounted separately from the barriers. The barriers' swing range is therefore independent of the monitored areas. This allows paths "around corners" to be monitored.

[0042] In one embodiment, object detection takes place in at least two areas. A monitored area A (the swing area of ​​the barrier) must be free of objects, regardless of whether they are stationary or moving. In the other area B, the position, direction, and speed of objects are detected. The barrier opens when area A is free of objects and an object in area B approaches the barrier at the correct angle and with sufficient speed. "Parallel runners" (objects moving parallel to the barrier or the monitoring boundary A / B) do not trigger the opening.

[0043] "Returning" individuals who pass through a randomly opened barrier are detected by their speed and direction of travel and, in one configuration of the barrier device, trigger an alarm as soon as area B is entered from area A. This method of evaluating the detected movements can replace a physically implemented "airlock" with two barriers arranged one behind the other in the direction of travel.

[0044] The detection of objects and their behavior in one configuration of the barrier device is based on cluster analysis, which calculates the object's position from the LiDAR data points. Of the various types of cluster analysis, one appears advantageous and well-suited for practical use, as it is suitable for running on a microcontroller with limited memory and processing speed, given the amount of data involved (number of data points). The cluster analysis to be used can be preferably selected based on these criteria.

[0045] In one design of the barrier device, data exchange between the LIDAR sensors takes place via a radio system and is therefore wireless.

[0046] In one configuration of the barrier device, mechanisms are included that can detect a system failure (e.g., of the rotation) or a laser failure based on the supplied data. The control unit can be designed in such a way that, in such a case, an error message is automatically generated and transmitted to a central control unit, enabling maintenance work to be initiated. If a failure of the rotation or timing of a LIDAR sensor is detected, one configuration of the barrier device automatically switches off the laser in accordance with laser safety regulations, in order to prevent any resulting localized damage from the laser beam (e.g., to the eye, directly or after a reflection) caused by the standstill.

[0047] Since not only the rotary drive but also the laser itself is subject to an aging process, one design of the barrier device incorporates markers to help monitor the beam intensity as part of its operating mode. These markers can be special reflective elements specifically positioned within the detection range of a sensor, or they can be elements already present within the detection range, such as a wall or column of a building. In the latter case, a calibration is first performed to establish the reflected beam intensity as the target value. A warning, which can be described as a wear indicator, can be automatically triggered if a predetermined deviation from the target values ​​occurs. The affected components can then be proactively replaced before a malfunction occurs.The affected components could be, for example, the markers, e.g. in the case of damage, or it could be the laser itself, e.g. due to the aforementioned aging.

[0048] The aforementioned developments and improvements can be implemented individually, or two or more of them can be implemented in any combination, provided they are not mutually exclusive, e.g., in the form of alternatives, as explained using the barriers arranged either as a double barrier side by side or as an airlock one behind the other. The described developments and improvements can be particularly advantageously implemented in an object as described in DE 20 2022 101 749 U1; however, they can also be applied to differently designed access and egress control systems, unless this is precluded by a technical impossibility.

[0049] Additionally, the following should be noted: With the availability of Time-of-Flight (ToF) sensors, it is possible to obtain a direct distance measurement by measuring the travel time of an electromagnetic wave, i.e., by measuring time and the constant propagation speed. While an even more precise method would be possible using interferometric measurement, this requires referencing, precise knowledge and stability of the wavelength, as well as other prerequisites for its application. Both of these are one-dimensional measurements.

[0050] Spatial measurements using Time-of-Flight (ToF) technology are possible with camera systems. A dot pattern is projected into space. The individual measurements of each point allow conclusions to be drawn about the spatial dimensions of the contour. This is a matrix measurement, where each field corresponds to a distance. This 3D measurement requires a complex sensor setup.

[0051] Two-dimensional distance measurement is achieved using a rotating Time-of-Flight (ToF) sensor. Each angle then provides distance information perpendicular to the axis of rotation. This method presents only a mechanical challenge due to the rotation. The actual ToF sensor still operates in one dimension. This allows for a very simple electronic design, which is reflected in the cost. LiDAR sensors are therefore widely used, for example in consumer products such as autonomous robotic vacuum cleaners, where the sensor is both permanently attached to the mobile device and also independently mounted. This enables the device to detect obstacles in its path. The rotational principle of LiDAR sensors provides angular information and distances relative to the direction of travel.

[0052] The present invention takes a different approach. Here, the LIDAR is permanently installed to detect moving objects. Unlike light barriers, which only operate in one dimension and require multiple units and adjustments for spatial monitoring, or simple radar sensors, which can only detect moving objects without direction recognition, a fixed LIDAR sensor mounted parallel to the plane on which the objects move enables the monitoring of an entire two-dimensional area and detects objects regardless of whether they are stationary or moving. Because the measurement is performed rotating, moving objects transmit their position changes within the rotational speed and thus, in addition to their velocity information, also their direction of movement.

[0053] Based on a very inexpensive sensor, this provides information that would otherwise only be obtainable with much more complex systems. These include, for example, camera systems that can locate or even track objects or people using image processing. However, image processing requires considerable effort and therefore more energy. Furthermore, a camera usually has to be mounted "overhead" to track objects. However, orthogonal mounting to the monitoring plane is often not possible due to limited ceiling height, especially if the camera is to be positioned at a height protected from vandalism and accidental damage. Cameras can also be susceptible to interference due to lighting conditions (sunlight), which can vary depending on the time of year and / or day. In contrast, the LIDAR-based barrier system according to the invention operates parallel to the plane of movement.The detection height above the monitoring or movement plane can be individually adjusted. Because top-down mounting is not required, this system is easy to install and is also suitable for angled areas, such as L-shaped ones. The cost advantage allows for the easy combination of multiple LiDAR sensors, thus optimizing the localization or tracking of objects within the monitored area. Combining two or more LiDARs is straightforward. Since each system is permanently mounted and therefore fixed, their relative positions are also unchangeable. The data supplied by a LiDAR sensor corresponds to polar coordinates, which, according to the invention, are automatically transformed into another coordinate system, such as Cartesian. This transformation is performed in such a way that the Cartesian position of each individual LiDAR sensor is also taken into account.This allows each individual measurement point from each LiDAR sensor to be plotted in the common coordinate system. It doesn't matter which LiDAR sensor provided which measurement point; the XY data can simply be aggregated.

[0054] It must be assumed that the measurements contain errors and that the objects to be located also have a certain size. Therefore, identical positions will never be obtained. For this reason, each object is represented by a point cloud with a specific extent. Ideally, the center of this point cloud represents the object's position. Statistically speaking, the accuracy of this representation increases with the number of measurement points, regardless of which LiDAR sensor they originate from.

[0055] If one of the multiple LiDAR sensors is obscured or malfunctions, the localization accuracy will decrease slightly because the point cloud will shift. However, a complete failure is not to be expected, so the barrier system's functionality can still be guaranteed.

[0056] Regarding the evaluation of the point cloud(s), multiple point clouds must be considered, as various objects may be located in the monitored plane. These point clouds require differentiation so that not all measurements are combined into a single point cloud, but rather each individual point cloud represents an object, and the evaluation provides a localized position for that object. A mathematical-numerical method for this is cluster analysis, which allows the number and density of the point clouds to be selected to obtain optimal positions that correctly represent the objects in the plane.

[0057] If localization occurs sufficiently quickly, it is possible to determine not only the speed of movement over time, but also, by observing changes in position, the direction of movement of an object – or, if there is no change in position, its resting position. These two properties, in particular, are otherwise only provided by significantly more complex systems. Thus, with a barrier system designed according to the invention, information is available using technically simple and cost-effective means, enabling a qualified assessment of the detected objects.

[0058] As described above, a single sensor, or multiple sensors, provide the position of a stationary or moving object within a common coordinate system. The number of LiDAR sensors providing data is irrelevant, as long as at least one LiDAR sensor is active. This is crucial for the fault tolerance and reliability of the barrier system. If a sensor or a segment of a sensor is temporarily obscured, the impact on the object's position is minimal, provided the object is also detected by one or more other sensors or the obscuration lasts only a few seconds. This is particularly relevant for areas with high object movement, such as entrances or exits frequented by people.

[0059] Because individual people can be located at the movement or monitoring level, and because their dynamics can be recorded, it is possible not only to determine the number of people, but also their direction and speed of movement, in addition to unusually rapid movements or prolonged periods of inactivity. Many conclusions can be drawn from this group, subgroup, or individual analysis.

[0060] For example, if many objects / people move quickly and together in one direction, it can be assumed that this is an escape movement, allowing the control unit to automatically activate an emergency mode of the barrier system. In this mode, all barriers are automatically opened, and an additional alarm may be triggered. If a single object moves improperly against a predetermined direction, it can be identified as a "reverse" or "opposing" person. If individuals remain stationary for a certain period of time on opposite sides of a boundary or dividing line, this situation could also be detected and lead to an automatic alarm, for example, to counteract an attempt to effect an unauthorized transfer across a barrier.

[0061] Furthermore, a cumulative count of objects is possible to determine how many people are present at a location at a given time. Even if the entry and exit areas are identical, direction detection enables simultaneous counting of arrivals and departures. The analysis of movement patterns can be performed using AI, which can distinguish between "normal" and atypical dynamics. A simple count based on crossing virtual boundaries is also feasible.

[0062] When used in access control systems that use barriers or doors to open or close an entrance or exit, these functions can be automatically triggered based on movement dynamics. If a person approaches the barrier at a certain speed and in a specific direction, this movement pattern can be used to initiate an opening or closing process. If a person approaches very slowly or in a less direct direction, triggering is not yet necessary, thus avoiding unnecessary operation.

[0063] In the case of a rotating or pivoting barrier, it is possible to partially, slowly, or not at all trigger it in order to prevent a collision with stationary or approaching persons within its pivoting range. The automatic collision monitoring system can be designed to implement anticipatory monitoring, in which a potential collision is predicted based on the object's speed and direction, as well as the speed at which the barrier is moving. Consequently, the movement of the barrier is aborted, delayed, or not initiated in the first place.

[0064] The described functions of the barrier system according to the invention are possible because each individual LIDAR sensor performs a rotational movement of several revolutions per second, scanning its radii and providing the distance and angle upon reflection. Both the conversion to Cartesian object positions and the cluster analysis are implemented in one embodiment of the barrier system based on microcontrollers that filter and condense all object properties. This occurs continuously at defined short intervals, so that the speed and direction of the objects are reliably and automatically determined. Biometric evaluation is therefore not possible. The movement profiles could, in principle, be stored. However, assignment to individuals is not possible. Apart from registering the number of people, malfunctions, or other cycles for service purposes, no data is collected.Despite the continuous calculations, no complex system is required, such as a computer system based on PC architecture. Since all calculations and control processes are performed on microcontrollers, minimal energy consumption and a small form factor are necessary. The system, particularly with regard to its own computing and control units, is very energy-efficient, and because it does not require a complex operating system, it is highly reliable and requires little maintenance.

[0065] In lower-level geodesy, methods are known for determining locations in a plane through trilateration and / or triangulation. These locations are landmarks or similarly unchanging points. This means that if geodetic measurements do not yield identical results, they are essentially due to measurement errors, since the locations themselves typically remain unchanged. Therefore, geodesy employs least squares adjustment procedures, which ultimately derive from the "method of least squares." In this process, the determined positions are shifted until the error is minimized.

[0066] In the barrier system according to the invention, the measurements are also subject to errors; however, the measured—in this case, scanned—positions are in most cases considered non-static. Geodetic methods might be applicable, but would yield inferior results because outliers or other disturbances could hardly be filtered out. The automatic evaluation of the measurement data provided for in the invention is based on the fact that the measurements form a cluster and the location represented by this cluster lies at the center of the cluster. As many measurements as possible are performed, and it is assumed that the vast majority of represented locations are at the center of the respective cluster formed. It is advantageous that it does not matter which sensor contributed data points to the "cluster cloud" and how often. Accordingly, many measuring devices / LIDARs can provide data simultaneously.The only requirement is that the data are in the same reference system, preferably a Cartesian one. This condition can be met if the location of each individual LIDAR and its relative position to each other are also known.

[0067] A LiDAR provides a distance and an angle with each measurement. It therefore maps a polar coordinate system, which can be transformed into a Cartesian coordinate system. By shifting the coordinates using an offset, the centers of multiple LiDARs can be aligned to a common center. In this system, all measurements from the multiple LiDARs are combined and subjected to cluster analysis. This is a fundamental difference from the geodetic methods of trilateration, triangulation, and least squares. In geodetic least squares, each measurement point exists only once. With cluster analysis, it is actually advantageous if each point is captured multiple times, ideally by different LiDARs, i.e., from different directions. Cluster analysis, as used in many big data applications, directly maps the desired location.It can be assumed that errors resulting from the large number of measurements of the identical object largely average out due to statistical reasons.

[0068] In one configuration of the barrier system, a cost-effective (consumer) LiDAR with a measurement frequency of 4500 Hz, meaning 4500 measurements across 360° per second. Since the LiDAR rotates at approximately 10 revolutions per second, the 360° plane of rotation is captured 10 times per second with approximately 450 measurements. Each reflection point within the plane of rotation is therefore captured up to 10 times per second. Due to the short cycle time of 0.1 s and the expected maximum movement speed of people of approximately 2 m / s, a maximum deviation of 200 mm between successive positions can be expected. This value, which is smaller than the expected object dimensions, is acceptable, especially since successive measurements would exhibit almost identical deviations relative to each other, thus having little impact on the direction and speed measurements.

[0069] Successive position measurements and their time intervals yield an object's velocity. Since multiple measurements are taken per second, the object's velocity can also be determined with good accuracy. Furthermore, the consecutive positions of an object derived from cluster analysis also provide information about its direction of movement. It is expected that the number of clusters found corresponds to the number of objects within the scan area. If the objects cross a predetermined boundary, incrementing or decrementing (in the opposite direction) allows, for example, counting. If the extent of a cluster is also included in the analysis, objects and their behavior can be differentiated with sufficient precision (e.g., person or goods).

[0070] All determined parameters, such as size, velocity, direction, and position, together allow for a behavioral analysis / assessment of the LiDAR-scanned object. The LiDAR scanner is relatively inexpensive, and the described evaluation of the combined LiDAR data is possible using embedded electronics, i.e., without the use of a PC, thus supporting the most economical design of the barrier system. Commercially available and therefore inexpensive components, which may optionally incorporate PC technology, can be used for data storage and / or transmission. Using as little PC technology as possible in a barrier system according to the invention is advantageous because a larger, more complex operating system can be considered a universal tool that offers many opportunities for misuse in the event of external attacks.Embedded electronics, on the other hand, are highly specialized for their intended use, therefore offering little additional functionality and thus hardly any room for harmful elements.

[0071] The present invention is explained in more detail below with reference to purely schematic drawings. These drawings show Figs. 1 and 2: Point curves of the same object, detected by two LiDAR sensors of a barrier system, in two different polar coordinate systems; Figs. 3 and 4: The point curves of the detected object, each transformed into Cartesian coordinate systems; Fig. 5: The two point curves, transformed into a common Cartesian coordinate system; and Fig. 6: The representation of the position of an object calculated from the two point curves in the coordinate system of the Fig. 5 .

[0072] The Fig. 1 and 2The images show the same object, detected by two different LiDAR sensors, located within the detection range of a barrier system. Because the LiDARs are mounted in different locations, they detect the identical object from different angles and distances. Fig. 1 The object is shown as a curved line of points located in the lower right quadrant and at a distance of between 600 and 800 from a first LIDAR sensor. Fig. 2 The same object is shown as a point curve in the upper right quadrant at a distance of 400 to 500 mm from a second LiDAR sensor. The unit for distance is mm in both cases, purely for illustrative purposes. Both LiDAR sensors provide their measurement results in a polar coordinate system, with each sensor located at the origin.

[0073] The representation of the measurements is not 100% accurate, but rather purely illustrative and schematic. Unlike the depicted point curves, which are concave towards the origin, the point curves for people detected by the sensor would be exactly the opposite, i.e., convex with respect to the origin. However, this is irrelevant for describing the process by which the measured values ​​are evaluated.

[0074] The Fig. 3 and 4 show the same object from the two polar coordinate systems of the Fig. 1 and 2 after a transformation into Cartesian coordinate systems. This represents Fig. 3 the measured values ​​of the first LIDAR sensor and represents the transformation of the Fig. 1 represented in Cartesian coordinates, while Fig. 3 the measured values ​​of the second LIDAR sensor according to Fig. 2 as a transformation into Cartesian coordinates. The pole of the polar coordinate system is the origin of the Cartesian system. This also applies to the Cartesian coordinate systems of... Fig. 3 and 4 The LiDAR sensors are each located at the origin of the coordinate system, where the zero lines intersect. Apart from the respective point curves, which are located in the lower right quadrant for the first LiDAR sensor and in the upper right quadrant for the second LiDAR sensor, the Fig. 3 and 4 including the LIDAR sensors themselves, each represented by a point at the origin of the coordinate system.

[0075] The relative positions of the stationary LIDAR systems are known. Therefore, based on the representations of the Fig. 3 and 4 to transform the individual, different Cartesian LIDAR coordinate systems into a common coordinate system by means of an offset transformation, which is then Fig. 5 The position of the first LiDAR sensor is shown as a point in the upper left of this coordinate system, and the point curve associated with this first LiDAR sensor runs in an arc from the lower left upwards to the upper right. The second LiDAR sensor is shown as a point in the lower left of this coordinate system; its point curve runs in an arc from the upper left downwards to the lower right and intersects the point curve of the first LiDAR sensor.

[0076] Converting the data to a common coordinate system simplifies the merging of different LIDAR data.

[0077] Since detected objects always have an extent that exceeds the beam thickness of the LiDAR laser beam, and because the LiDAR scans the object surfaces very quickly and from different angles, a point pattern is generated in a short time, representing the scanned surface and depicted as an arc or curve in the example shown. The point pattern reflected from the surface—the depicted point curve—corresponds to the surface structure of the object and can vary considerably because it was scanned from different angles. Therefore, interpolating surface lines, such as the depicted point curve, is insufficient to accurately determine the object's position.

[0078] The informational value of the recorded points lies in their extent. Since this was recorded from various angles, cluster analysis can be used to automatically determine the "core" of these extents with sufficiently good accuracy. This "core" or center of gravity corresponds to the most probable or typical location of the object and can be considered a very good approximation of its location.

[0079] Fig. 6 shows the representation of Fig. 5However, the calculated "core" or center of gravity, resulting from the cluster analysis, is also plotted as the object's most probable location. In the example shown, this location lies approximately at the intersection of the two point curves. Cluster analysis is capable of simultaneously capturing multiple clusters. Therefore, when using multiple LiDAR sensors, the several point curves resulting from the detection of the same object can be processed, and multiple objects can be detected simultaneously. The number of LiDAR sensors involved is irrelevant. Every transmitted coordinate point is included in the cluster analysis. Furthermore, it is irrelevant whether individual LiDARs are shaded or individual LiDAR measurements are lost, as the large number of individual measurements or measurement points, based on the rotational speed and measurement frequency of the LiDAR sensors, results in a high error tolerance for the barrier system.The impact on localization is minimal because the measurements follow each other very quickly. Therefore, simultaneous movement of an object also has no significant effect, as the measurement frequency is high compared to the speed of movement and also scales with the number of LIDARs.

[0080] The latter is even sufficient for the rapid, repeated localization of an object to simultaneously determine its speed and direction. From this data, movement and standstill patterns can be automatically calculated. This allows, for example, the control unit of a barrier system to react automatically in a targeted manner or trigger alarms.

Claims

1. A barrier device for a passage in a passage space in which objects are at least temporarily located, • having a barrier having a blocking means and a holding element, wherein the blocking means is able to move relative to the holding element between a clearance position that opens the passage and a blocking position that closes the passage, • and having a capture apparatus having a signal transmitter and a signal receiver, wherein the signal transmitter outputs laser pulses generating a planar capture field that captures at least regions of the passage space, and wherein the signal receiver captures the laser beams reflected by objects located in the passage space, • and having an evaluation unit that determines the time of flight of the reflected laser beams, • wherein the capture field is oriented substantially parallel to the horizontal plane, and wherein, the barrier device has a computing unit that derives an object movement from the time of flight, namely in the manner of a direction of movement and a speed of movement of the captured objects in the passage space, wherein the barrier device has an automated control unit that is connected to the computing unit and to the barrier so as to be able to transmit signals, and which prompts a change of position between the clearance position and the blocking position on the basis of the determined object movement, wherein the barrier device has multiple capture apparatuses designed as lidar sensors und multiple signal transmitters, characterized in that the evaluation unit is designed to determine a multiplicity of times of flight for each position of an object and the computing unit is designed to derive a concretized direction of movement and speed of movement from multiple times of flight when computing the object movement, wherein the respective multiplicities of times of flight determined by the multiple capture apparatuses designed as lidar sensors give rise to a respective multiplicity of individual points of the same object, referred to as a point curve, and the computing unit is designed such that • this point curve is present in a polar coordinate system, • the point curve is then transformed automatically into a Cartesian coordinate system, • the point curves of the multiple lidar sensors are then converted automatically into a common Cartesian coordinate system, • wherein the Cartesian position of each individual lidar sensor is also computed alongside, and • the probable position of the object is then computed automatically from the multiple point curves representing the same object in the common coordinate system.

2. The barrier device as claimed in claim 1, wherein the signal transmitter is arranged in, on or next to the barrier.

3. The barrier device as claimed in claim 1 or 2, wherein the signal transmitter is arranged level with the blocking means at a distance from a ground surface supporting the objects.

4. The barrier device as claimed in claim 3, wherein the signal transmitter is arranged at a height of between 20 cm and 80 cm above the ground surface.

5. The barrier device as claimed in one of the preceding claims, wherein the signal transmitters generate capture fields that are arranged parallel to one another and shifted in relation to one another in the vertical direction.

6. The barrier device as claimed in one of the preceding claims, wherein the signal transmitter is mounted so as to be able to move in rotation about a substantially vertically oriented axis of rotation and is designed to capture at least sections of a circular ring-shaped capture field around the signal transmitter.

7. The barrier device as claimed in one of the preceding claims, wherein the capture field has a trigger region, in the passage space, in which the barrier is arranged and within which an at least temporarily paused object triggers clearance by the control unit.

8. The barrier device as claimed in one of the preceding claims, wherein the computing unit is designed such that the probable position of the object is computed automatically by way of a cluster analysis.

9. The barrier device as claimed in one of the preceding claims, wherein the capture field is oriented at an angle of 0 to 10° to the horizontal plane.

10. The barrier device as claimed in one of the preceding claims, wherein the control unit prompts an object-dependent movement such that, based on the determined object movement, the blocking means moves only to the extent necessary to clear the passage.

11. The barrier device as claimed in one of the preceding claims, wherein the control unit sets the opening or closing speed of a blocking means on the basis of the object speed of movement.

12. The barrier device as claimed in one of the preceding claims, wherein the movement of the blocking means in the passage space creates a collision space, and wherein the computing unit derives a current position of an object in the collision space and / or a position derived from a direction of movement and speed of movement and the control unit controls the movement of the blocking means so as to prevent a collision.

13. The barrier device as claimed in one of the preceding claims, wherein the barrier device has multiple blocking means and / or segmented blocking means that are able to be controlled separately.

14. The barrier device as claimed in one of the preceding claims, wherein a counting unit is arranged and intended to count the objects that pass through the passage.

15. The barrier device as claimed in one of the preceding claims, wherein the passage is an entrance and the capture field captures regions of the passage space located in front of and behind the barrier in the entrance direction, and wherein the barrier device has an alarm device that is triggered when an object passes through the barrier in the manner of an exit in the opposite direction to the entrance direction.

16. The arrangement of a barrier device in order to regulate a passage in a passage space of a shop, hotel, office building or the like in which objects are at least temporarily located, characterized in that the barrier device is designed as claimed in one of the preceding claims.

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