TRAFFIC MONITORING SYSTEM AND METHOD FOR MONITORING A DISTANCE

Description

[0001] The invention relates to a traffic monitoring system and a method for monitoring a lateral distance between an overtaking vehicle and a road user being overtaken, preferably a bicycle.

[0002] Maintaining a sufficient distance between road users is a crucial safety requirement, as insufficient distance can significantly increase the risk of accidents. Sufficient distance is particularly important during overtaking maneuvers, where a vehicle passes another road user. Especially when overtaking bicycles, an insufficient distance between the overtaking vehicle and the bicycle can lead to serious accidents, such as falls. The larger and faster the overtaking vehicle, the stronger and more dangerous the airflow it generates, which can push a bicycle sideways or pull it towards the road, and in the worst case, even knock it over.Therefore, many countries prescribe a minimum distance that a vehicle must maintain from a vehicle being overtaken during an overtaking maneuver. In Germany, for example, this is regulated in Section 5 of the Road Traffic Regulations. However, a problem arises because monitoring compliance with this distance using automated systems is difficult. Monitoring by police or other enforcement officers is costly and can usually only be carried out on a random basis.

[0003] Several systems are known in practice that, in principle, allow monitoring of the distance between a bicycle and an overtaking vehicle. For example, an article by Joachim Kroll, dated August 22, 2018, is available at http: / / www.elektroniknet.de and refers to distance measurement using an Arduino system. In this system, a device with ultrasonic sensors is attached to the bicycle. The ultrasonic sensors measure the lateral distance of overtaking vehicles to the left and right of the bicycle. If a minimum distance is breached, a warning is transmitted via Bluetooth to a connected smartphone. The smartphone can then issue the warning and take a photo of the overtaking vehicle for documentation purposes.

[0004] A similar system is sold by Garmin under the model name Varia RCT716. In addition to functioning as a taillight, the device uses a radar sensor to detect the distance to approaching vehicles. If a vehicle approaches quickly or overtakes too closely, the device generates a video sequence documenting the event.

[0005] These bicycle-based systems offer the advantage of documenting dangerous behavior by an overtaking vehicle in the event of a dispute or accident. Because the bicycle serves as the reference point, these systems can be relatively simple in terms of sensor technology. However, a disadvantage is that these systems can only monitor overtaking maneuvers involving a specific bicycle. General traffic monitoring, which would allow for maintaining a safe distance similar to general speed enforcement, is therefore not possible. While a general rollout of such systems to all cyclists would be conceivable, this is neither practical nor would the results be admissible as evidence by law enforcement. Furthermore, this solution would involve considerable costs.

[0006] DE 10 2019 107 279 A1 discloses a system for detecting a breach of a permissible distance between a following vehicle and a leading vehicle.

[0007] From EP 3 912 888 A1, an overtaking assistant can be taken, with which a vehicle driver can be warned before a lateral distance to an overtaken vehicle is reduced.

[0008] Comparable systems are known from DE 10 2019 005 497 A1 and WO 2022 / 233676 A1.

[0009] The invention is based on the objective of providing a traffic monitoring system and a method that allows monitoring of the lateral distance between an overtaking vehicle and a road user being overtaken. It is desirable for the traffic monitoring system to be able to operate automatically.

[0010] This problem is solved by the combinations of features in the dependent claims. Further embodiments of the invention are disclosed in the respective subclaims.

[0011] It should be noted that the features listed individually in the claims can be combined with one another in any technically meaningful way without exceeding the scope of protection. The scope of protection is defined exclusively by the following patent claims.

[0012] The description further characterizes and specifies the invention, particularly in connection with the figures.

[0013] It should also be noted that the conjunction "and / or" used herein, which stands between two characteristics and links them together, is always to be interpreted in such a way that in a first embodiment only the first characteristic can be present, in a second embodiment only the second characteristic can be present, and in a third embodiment both the first and the second characteristic can be present.

[0014] It has been recognized that a monitoring system for tracking the distance between an overtaking vehicle and the overtaken road user can be designed as a stationary system, similar to a general speed control system. Such a distance monitoring system does not necessarily have to be a moving system with the overtaken road user as the reference point. Even though a stationary system increases the complexity of the sensors and data processing, it offers significant advantages and opens up a wider range of applications. In particular, it enables general traffic monitoring that warns road users of insufficient following distance or even allows for the enforcement of penalties for following too closely.

[0015] Such a system can include a measuring system that detects passing road users within a detection area. These passing road users can include a wide variety of vehicles, such as cars, trucks, two-wheelers, bicycles, e-scooters and / or electric kick scooters, as well as pedestrians and / or other road users. In particular, passing road users can consist of overtaking vehicles and / or overtaken road users. It simplifies matters that passing road users typically move in a known direction, namely in the direction of travel along a monitored road or section of a road. This means, firstly, that the detection area can be easily adapted to the specific traffic situation being monitored. Secondly, it is usually possible to distinguish relatively clearly between an overtaking and an overtaken road user.

[0016] In the following, such passing road users are also generally referred to as "objects in the detection area".

[0017] In general, the "measuring system" can be designed in various ways. The only essential requirement is that the measuring system has a detection range and that it can detect objects moving through or within this range. An object can be entirely within the detection range, at least temporarily. However, it is also conceivable that an object is only partially detected. In this case, the detected portion should be large enough to allow for object identification. Generally, the measuring system should be capable of generating measurements that are representative of objects within the detection range, particularly passing road users, and their respective movements. These requirements can be met by a wide variety of measuring systems.

[0018] The measuring system is designed to be "stationary." This means that the measuring system is not moved (or at least not to a significant extent) while generating measurements. This does not necessarily mean that the measuring system is permanently anchored to a surface, for example, via a mast embedded in concrete or mounted on a house wall, bridge pier, or wall. Rather, the measuring system (or the traffic monitoring system as a whole) can be portable and set up in a fixed location—that is, stationary—for a specific monitoring purpose.

[0019] The monitoring system further comprises an evaluation unit, a rating unit, a comparator, and a display and / or acquisition unit. The evaluation unit is connected to the measurement system and can receive measured values ​​from the measurement system via this connection. In principle, it is also conceivable that the measurement system and the evaluation unit are designed as integral components, meaning that the two components are distinguishable only in their function and not as separate units. The evaluation unit is designed to identify objects within the detection range based on the measured values. Its primary task is to identify objects as either an overtaking vehicle, a overtaken vehicle, or another type of object. For the purposes of this analysis, "identified objects" can be understood as anything that cannot be considered a stationary object.Such a stationary object could include, for example, the road itself, a roadside marker post, a traffic light, a street lamp, a parked car, a tree, and / or the like. The evaluation unit can also recognize these stationary objects itself by identifying unchanging measured values ​​over a certain period of time (for example, one or five minutes) as stationary objects and excluding them from further identification.

[0020] If only one object moves through the detection area, further processing can generally be aborted. However, it is also conceivable that this single object will be identified as an overtaken road user, since an overtaking vehicle can also enter the detection area at a later time. Identifying an overtaking vehicle requires that an overtaken road user is present, as an overtaking maneuver is not possible without one. Ideally, the overtaking vehicle and the overtaken road user are simultaneously within the detection area. However, the overtaken road user may have left the detection area shortly before the overtaking vehicle is detected or may enter the detection area shortly after the overtaking vehicle leaves it. This can also, in principle, still be interpreted and evaluated as an overtaking maneuver.The term "short" likely depends on the speed of the objects. In most cases, "short" will probably be in the range of a few seconds, but for the sake of accuracy when extrapolating the movements of the objects, it should ideally be in the range of one second or less.

[0021] In principle, an "overtaking vehicle" can be any type of vehicle. Regulations regarding maintaining a minimum distance are often not limited to specific vehicles or vehicle types. For example, a bicycle overtaking another bicycle must also maintain a minimum distance. However, since larger vehicles pose a significant risk, the term "overtaking vehicle" typically refers to a motor vehicle, i.e., a vehicle powered by an engine and not bound to rails. This can include a passenger car, a truck, a tractor, a motorcycle, a motorized cargo bike, a motorhome, agricultural machinery, or similar vehicles. A characteristic of an overtaking vehicle is that it travels in approximately the same direction as the overtaken road user but at a higher speed.In right-hand traffic, the overtaking vehicle is usually positioned to the left of the vehicle being overtaken. In exceptional situations, overtaking can also occur on the right, for example, at turning lanes. In left-hand traffic, this is reversed.

[0022] A "road user being overtaken" can be any road user who can be overtaken by an overtaking vehicle, generally assuming that both the overtaking vehicle and the road user being overtaken are moving in approximately the same direction. A road user being overtaken can, in principle, also be a pedestrian. In one interpretation, this refers to vehicles not bound to rails. These vehicles can be powered by either a motor or muscle power. In another interpretation, a "road user being overtaken" refers to single-track vehicles, particularly bicycles, e-bikes, or pedelecs. An insufficient distance is especially dangerous with such road users.

[0023] The evaluation unit is designed to determine distances between objects within its detection range. Additionally, the evaluation unit can be designed to determine the speed and / or size (preferably width and / or height) of objects within the detection range. For this purpose, the evaluation unit can be connected to the measurement system and receive its measurement data. Distances between all objects within the detection range can be determined, regardless of whether the object is stationary, an overtaking vehicle, a vehicle being overtaken, or any other type of object. To increase the efficiency of the monitoring system, the evaluation unit can utilize information about the identified objects when determining distances. For this purpose, the evaluation unit can be connected to the evaluation unit and receive information about the identified objects.In this way, distance determination can be reduced to the relevant objects, namely overtaking vehicles and overtaken road users that are in the detection range at the same time and / or within a predefined time window. The latter applies to the previously mentioned case where the overtaking vehicle and the overtaken road user are not in the detection range at the same time, but the overtaking vehicle or the overtaken road user enters or leaves the detection range shortly beforehand. The same applies if speed and / or size are optionally recorded.

[0024] In principle, a measured distance can refer to various distances between any two objects. In one embodiment, "distance" is understood as a gap, i.e., between points on the overtaking vehicle and the overtaken road user that are at a minimum distance from each other. Since the present disclosure is intended to monitor the distance between the overtaking vehicle and the overtaken road user during an overtaking maneuver, the point in time at which the overtaking vehicle and the overtaken road user come particularly close to each other and / or at which the greatest danger to the overtaken road user exists is of particular interest. Therefore, in one embodiment, the measured distance is a lateral distance.If the location of the shortest distance should be before or after the detection range of the measuring system, the shortest distance can also be extrapolated - within certain limits.

[0025] The comparator is designed to compare distances between objects within the detection range, as determined by the evaluation unit, with a minimum distance and, based on the result of this comparison, to generate and output a trigger event. For this purpose, the comparator is connected to the evaluation unit and can receive distance values ​​determined by it. Additionally, a minimum value can be entered into the comparator, for example, from memory. In one embodiment, the comparator can receive the distances, compare them with the minimum value, and output a trigger event if the distance falls below the minimum value. It is also conceivable that the comparator compares the distance values ​​with several threshold values ​​and outputs different trigger events. For example, an initial trigger event could signal that a sufficiently large distance has been detected.In this case, the comparator can compare a distance with the minimum value and, if the difference between the distance and the minimum value is sufficiently large, generate and output a "Distance OK" trigger event. This comparison can also be performed using a second threshold. A second trigger event can indicate that while the distance is not too small, a greater distance is still advisable for safety reasons. In this case, the comparator can compare a distance with the minimum value and, if the distance is greater than the minimum value but still shows a small difference between the distance and the minimum value, generate and output a "Distance borderline" trigger event. This comparison can also be performed using a third threshold. A third trigger event can indicate that the minimum distance has been breached.In this case, the comparator would compare a distance with the minimum value and, if the distance falls below the minimum value, generate and output a trigger event "Distance too short". This trigger event can also include the calculated distance. These examples of comparators and generated trigger events, which are neither exhaustive nor limiting, illustrate how flexible this concept can be.

[0026] A "trigger event" is, generally speaking, a message that represents a result of the comparator's comparison and is simultaneously linked to an action to be initiated. The trigger event may contain only simple activation information. However, it can also contain more comprehensive information, such as a timestamp, a measured distance, a used threshold, or a measurement duration. The trigger event can be implemented in a variety of ways. In particular, it can be an analog or digital signal, or an analog or digital signal sequence. In one implementation, a trigger event can be a voltage level that assumes a first level when a trigger event is activated and a second level otherwise, whereby the two levels should be clearly distinguishable from each other. This allows for particularly fast transmission of the trigger event.In another configuration, a trigger event can consist of one or more data packets structured according to the Internet Protocol or another digital transmission protocol. This enables or simplifies transmission via a wide variety of standardized communication interfaces, and allows for the transmission of a relatively large amount of information with such a trigger event. This brief list, which is neither exhaustive nor limiting, demonstrates the flexibility with which a trigger event can be structured and implemented.

[0027] The display and / or detection unit can be configured to execute an action based on a trigger event. For this purpose, the display and / or detection unit is communicatively connected to the comparator and can receive a trigger event in this way. In one embodiment, the action can involve a camera capturing the overtaking vehicle. In another embodiment, the action can involve issuing a warning to the overtaking vehicle, for example, via a light signal. Using the aforementioned examples of trigger events, the trigger event "distance too short" can trigger the camera to capture an image or video of the overtaking vehicle. Additionally or alternatively, a light signal, such as a red symbol, can be displayed to the overtaking vehicle.When a trigger event "distance too close" is received, the display and / or detection unit can show the overtaking vehicle a corresponding warning, indicating to the driver that the distance should be increased. This could be, for example, an orange icon. In this way, drivers can better judge distances to overtaken vehicles during future overtaking maneuvers. If a trigger event "distance OK" is received, this trigger event can result in the action "ignore". To motivate drivers, positive feedback can also be provided, such as a green light, a smiley face, a thumbs-up, or other similar indicator. These examples are neither exhaustive nor limiting and are intended only to illustrate the function of the display and / or detection unit.

[0028] The individual components of the traffic monitoring system, such as the measuring system, the evaluation unit, the assessment unit, the comparator, and the display and / or recording unit, can be designed and / or implemented in a variety of ways, as long as the aforementioned properties, or at least some of them, are achievable. In one embodiment, the components of the traffic monitoring system can be implemented entirely in hardware. In another embodiment, the components are implemented through a combination of hardware and software. The hardware can include sensors (e.g., radar sensor, camera, infrared camera, ToF sensor, LiDAR, etc.).The components of a traffic monitoring system include analog-to-digital converters, filters (such as high-pass, low-pass, and band-pass filters), one or more processors (such as microcontrollers, digital signal processors, or ASICs (application-specific integrated circuits)), and / or programmable logic circuitry (such as FPGAs (field-programmable gate arrays) or CPLDs (complex programmable logic devices)). Furthermore, one or more memory modules may be present, such as RAM (random access memory), ROM (read-only memory), flash memory, hard disk(s), or SSD (solid-state drive), which other hardware components can access. Software can control the individual components of the traffic monitoring system and their interaction.

[0029] In one configuration, the evaluation unit is designed to identify objects based on their dimensions and / or their position within the detection area. This method is particularly useful for distinguishing between overtaking motor vehicles and overtaken bicycles. Motor vehicles are generally quite wide, typically at least 1.60 meters, and usually considerably wider. Bicycles, on the other hand, are relatively narrow (e.g., 60 to 80 centimeters) and relatively tall (e.g., 1.5 to 2.0 meters). This allows for differentiation based on dimensions. Furthermore, bicycles typically ride close to the edge of the road, while overtaking vehicles usually overtake to the left.Therefore, the position of the road users makes it easy to identify the overtaking vehicle and the overtaken road user.

[0030] In one embodiment, the evaluation unit is based on an AI (Artificial Intelligence) approach and preferably features a neural network for identifying objects within the detection area. This allows for particularly reliable object identification. Artificial intelligence relies on predefined prior knowledge and can therefore perform highly reliable identifications. For example, a neural network can be trained with a large number of measurements from a measurement system where the detected objects are known, such as known overtaking vehicles and known overtaken road users. In this case, it may be sufficient for the categories to be quite broad, such as "motor vehicle" and "bicycle."Further detailing can be advantageous for training the neural network, for example into categories such as cars, trucks, motorcycles and bicycles, to name just a few conceivable examples.

[0031] In one configuration, the measuring system includes a camera whose image can be used by the evaluation unit to identify objects within the detection range. In principle, the measured values ​​themselves can be used for object identification. However, it can also be advantageous to use a separate camera whose images are used for object identification. This camera could be an infrared camera, an RGB camera, a grayscale camera, or similar. This facilitates the use of established techniques, such as image recognition algorithms. Additionally, the images and / or videos from this camera could be used to document an overtaking maneuver.

[0032] In one embodiment, the measurement data from the measuring system includes information about distances between the measuring system and detected objects within the detection range. The evaluation unit is designed to determine the distances between objects within the detection range based on these distances. By detecting objects and their distance from the measuring system, the spatial classification of the objects can be improved. Using these measurement data to determine the distances between the objects can enhance the accuracy of the distance measurement.

[0033] In advanced training, the evaluation unit is trained to determine the distances between objects within the detection range as the difference between the measuring system and the detected objects within that range. This difference can usually be understood as a vector difference. In this way, distance determination is further simplified and reduced to a comparatively simple calculation of the edges of a triangle.

[0034] In one embodiment, the evaluation unit is designed to use reference points and / or reference lines in the measurement data from the measuring system when determining distances between objects within the detection range. This leverages the fact that the detection range contains not only overtaking vehicles and overtaken road users, but also, and especially, stationary objects. These stationary objects can include, for example, lines on the roadway, poles at the roadside, road marker posts, or similar features, and they have a known and constant distance between them. These reference points and / or reference lines can be used to determine distances. A line on the roadway could, for example, be the boundary lines of a bicycle path.Such reference points or lines may also have been explicitly installed for distance monitoring, for example painted on the road surface. In this way, distances can be determined using simple means.

[0035] In one embodiment, the evaluation unit for determining distances between objects within the detection range is designed to utilize a temporal profile within the measurement data of the measuring system. This allows for improved distance determination. The temporal profile can, for example, make the paths of the overtaking vehicle and / or the overtaken road user traceable and / or extrapolate them. An example of tracing a path occurs when the overtaken road user reduces the distance to the overtaking vehicle within the detection range for no apparent reason. An example of extrapolation occurs when the actual overtaking maneuver takes place immediately before or after the detection range. Since the paths of vehicles cannot change abruptly, the distance during the actual overtaking maneuver can be estimated very accurately.

[0036] In one embodiment, the measuring system comprises a radar system, preferably an FMCW (Frequency Modulated Continuous Wave) radar, a ToF (Time of Flight) camera, a stereo camera, or a LIDAR (Laser Imaging Detection and Ranging) system. A radar system enables high-resolution distance measurements with cost-effective sensor technology. Further developing the radar system with an FMCW radar, in which the transmission frequency is periodically varied over time, enables precise distance measurement along with additional velocity measurement. A ToF camera is a 3D camera system in which a captured scene is illuminated with light pulses, and the time elapsed until the reflections from an object are detected and evaluated. This allows reliable information about the three-dimensional position of an object to be acquired. In a LIDAR system, a laser beam scans a detection area.The travel time of reflected portions of the laser beam is recorded and analyzed. This allows for the acquisition of highly precise distance information. A relatively inexpensive measurement system can be built using a stereo camera.

[0037] In one embodiment, the measuring system comprises a hybrid system that combines several sensors. In a further development, this hybrid system includes, in addition to a camera (for example, an infrared camera or an RGB camera), another sensor, preferably a radar system, a ToF camera, a LiDAR system, or the like. A camera image could be used to control the acquisition by the other sensor. For example, if the camera image is used to detect an overtaking vehicle and the overtaken road user, it may be sufficient for distance determination to focus more precisely on only the portion of the potentially possible detection range in which the overtaking maneuver takes place. In this way, the acquisition process can be accelerated, and the generation of unnecessary measurement values ​​can be avoided.

[0038] In one embodiment, the measuring system is arranged relative to a monitored roadway such that at least one plane within the system's detection range is perpendicular to the roadway. This can be achieved, for example, by mounting the measuring system on a mast in an elevated position and creating a downward-facing detection range towards the roadway. A plane within the detection range can then be arranged perpendicular to the roadway. "Perpendicular" can refer, for example, to the roadway surface and / or the roadway's alignment (e.g., defined by lane markings). In the aforementioned example, the plane can also include the mast. This simplifies distance measurement.

[0039] In one embodiment, the measuring system, the evaluation unit, the assessment unit, the comparator, and the display and / or recording unit are arranged in a single housing. This creates a traffic monitoring system that functions similarly to a speed display board or a speed monitoring device.

[0040] In one embodiment, at least the measuring system and the display and / or recording unit are spatially separated, with the display and / or recording unit preferably receiving the trigger event wirelessly. Such spatial separation allows the detection range and the position of the display and / or recording unit to be optimized for the specific purpose. In a further embodiment, the evaluation unit, assessment unit, and / or comparator are located at the measuring system or within the measuring system's housing, thereby minimizing data transmission between devices. Wireless transmission of trigger events simplifies the installation of the traffic monitoring system, particularly in mobile systems.

[0041] In one embodiment, the evaluation unit, the assessment unit, and / or the comparator are located remotely from the measurement system and / or the display and / or acquisition unit. This allows the evaluation unit, the assessment unit, and / or the comparator to be outsourced to a cloud system, for example. Depending on the outsourced function, a sufficiently suitable communication connection may be required, for example, with regard to transmission speed, bandwidth, and latency.

[0042] In one embodiment, the display and / or detection unit is configured to issue light signals based on a trigger event, preferably indicating a breach of the minimum distance and / or adherence to the minimum distance. Issuing a light signal allows for a simple and easily perceptible display of the result to the driver of the overtaking vehicle and the overtaken road user. It is advantageous if the meaning of the light signal is easily perceptible to all involved. This can be achieved, for example, by a pictogram containing, for instance, a stylized car on the left, a stylized bicycle on the right, and a double arrow between the two.A warning when the minimum following distance is breached makes it easier for the driver of an overtaking vehicle to judge the distance for future overtaking maneuvers and reminds them of the rules regarding following distances. Furthermore, the distance can then potentially be increased to reduce the risk to the overtaken road user. A warning indicating that the minimum following distance is being maintained provides the driver of the overtaking vehicle with positive feedback about their overtaking behavior.

[0043] In one configuration, the display and / or recording unit is designed to generate a photo and / or video based on a trigger event that documents an overtaking maneuver by the overtaking vehicle. This allows for the documentation and, if necessary, enforcement of following distance violations.

[0044] In one embodiment, the traffic monitoring system additionally includes a logging unit, which is communicatively connected to the measuring system, the evaluation unit, the assessment unit, and / or the comparator. The logging unit is configured to store and / or evaluate events recorded by the traffic monitoring system. Recorded events preferably include objects present in the detection area, detected overtaking maneuvers, determined distances, generated images, and / or generated trigger events. This allows for a better evaluation of a monitored location. For example, the logging unit can be configured to generate safety statistics that relate the number of passing vehicles and / or road users to the number of overtaking maneuvers and / or the number of following distance violations.The protocol unit can be implemented in a cloud, which can improve data storage and the availability of the information obtained.

[0045] In one embodiment, the traffic monitoring system includes a communication unit, preferably for communication via a wide-area network. This communication unit is designed to transmit trigger events, recorded photos, recorded videos, and / or measured values ​​to a control center and / or a logging unit. The communication unit enables communication between the traffic monitoring system and the outside world. This allows for external communication with the traffic monitoring system, for example, to configure the system or provide software updates. Conversely, the communication unit can be used to transmit various acquired information and / or status information to a control center.The various pieces of information gathered can include triggered events, photos / videos, and / or recorded measurements. Communicating trigger events allows for an assessment of the extent of distance violations. Sharing photos / videos can be used to penalize these violations. Communicating generated measurements allows for an evaluation of the measurement quality. A "control center" can be comprised of various facilities where the information is received and further analyzed. The logging unit can be configured according to the aforementioned specifications.

[0046] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments of the invention, which are not to be understood as limiting and are explained in more detail below with reference to the drawing. This drawing schematically shows: Fig. 1 a block diagram of an embodiment of a traffic monitoring system according to the present disclosure and Fig. 2 an oblique view of an application scenario of an embodiment of a traffic monitoring system according to the present disclosure.

[0047] In the different figures, parts that are equivalent in function are always provided with the same reference symbols, so that they are usually only described once.

[0048] Fig. 1 Figure 1 shows a block diagram of an embodiment of a traffic monitoring system according to the present disclosure. The traffic monitoring system 1 comprises a measuring system 2, an evaluation unit 3, a rating unit 4, a comparator 5, and a display and / or recording unit 6. The measuring system 2 has a detection range 7 within which the measuring system 2 detects passing objects (in Fig. 1not shown), in particular overtaking vehicles and / or overtaken road users (in Fig. 1(not shown) can detect. Measurement data obtained from passing objects is transmitted to evaluation unit 3 and assessment unit 4. Evaluation unit 3 identifies overtaking vehicles and / or overtaken road users in the received measurement data. Evaluation unit 3 can use an AI approach, such as a neural network, for this purpose. Assessment unit 4 uses the measurement data and the identification information obtained by evaluation unit 3 to determine distances between individual objects in the detection area 7, in particular overtaking vehicles and overtaken road users. The determined distances are transmitted to comparator 5, which compares them with an entered minimum distance 8. A trigger event is generated from the comparison result, which is output to display and / or detection unit 6.The display and / or detection unit 6 receives the trigger event and executes the associated action, for example, issuing a warning via a light signal 9 and / or taking a photograph with a camera 10 to document the overtaking maneuver. The light signal 9 and the camera 10 can be components of the display and / or detection unit 6.

[0049] The traffic monitoring system 1 can additionally include a memory 11 in which, for example, recorded measurements, generated trigger events, and / or generated photos / videos can be stored. Additionally, a timer (not shown) can be provided, which is used to generate a timestamp for information stored in the memory 11. The traffic monitoring system 1 can also include a control unit 12, which controls the functions of the traffic monitoring system 1. Furthermore, a communication unit 13 can be provided, which allows external communication, preferably radio-based communication, and preferably communication with a wide-area network, for example, a mobile network.

[0050] Fig. 2Figure 1 shows an application scenario for such a traffic monitoring system. The traffic monitoring system 1 comprises two individual devices, one of which is the measuring system 2 and the other the display and / or recording unit 6. Both devices are spaced apart from each other and are mounted at the top of a mast at the edge of a roadway 14 with a bicycle lane 15. The edge of the roadway 14 is marked by a lane boundary line 16. The bicycle lane 15 is separated from the driving area for other vehicles by a dividing line 17. A center line 18 indicates the center of the roadway 14. Lines 16, 17, and 18 can, in principle, be used for object identification and / or distance determination.

[0051] In the present case, the measuring system 2 is formed by a radar, for example, an FMCW radar. The detection area 7 of the measuring system 2 is essentially a cone with the roadway 14 as its inclined base and the measuring system 2 at its apex. The detection area 7 comprises a plane (not explicitly shown for clarity) that is perpendicular to the roadway 14 and parallel to the mast of the measuring system 2.

[0052] Various objects can pass through detection area 7. For example, in Fig. 2An overtaking maneuver is depicted in the detection area 7, in which an overtaking vehicle 19 overtakes a road user 20 (a bicycle). The measuring system 2 records a distance aA to the overtaking vehicle 19 and a distance aF to the overtaken road user 20, with the distances being measured relative to the measuring system 2. From the distances aA and aF, a distance a between the overtaking vehicle 19 and the overtaken road user 20 is calculated. The distance a is compared with a minimum distance 8 using a comparator 5 (not shown here), and a trigger event is output depending on the comparison result. The trigger event is transmitted wirelessly (in Fig. 2The data (symbolized by radio waves) is transmitted to the display and / or recording unit 6. LoRa or Bluetooth, for example, can be used for this purpose. Depending on the trigger event, the display and / or recording unit 6 performs an action, for example, displaying a colored pictogram to the overtaking vehicle 19 and the overtaken road user 20 via a light signal 9 (here a display), and / or taking a photograph of the overtaking maneuver for documentation purposes using a camera 10.

[0053] Regarding further advantageous embodiments, reference is made to the general part of the description and to the attached claims to avoid repetition.

[0054] Finally, it should be expressly pointed out that the exemplary embodiments described above serve only to illustrate the claimed teaching, but do not limit it to these exemplary embodiments. Reference symbol list

[0055] 1 Traffic monitoring system 2 Measuring system 3 Evaluation unit 4 Assessment unit 5 Comparator 6 Display and / or recording unit 7 Detection range 8 Minimum distance 9 Traffic signal 10 Camera 11 Memory 12 Control unit 13 Communication unit 14 Roadway 15 Bicycle lane 16 Lane boundary line 17 Dividing line 18 Center line 19 Overtaking vehicle 20 Overtaken road user

Claims

1. A traffic monitoring system for monitoring a lateral distance between an overtaking vehicle (19) and an overtaken road user (20), comprising: a measurement system (2) which is stationary and designed to generate measured values of moving objects in a detection area (7) of the measurement system (2), an evaluation unit (3) which is designed to identify objects in the detection area (7) as an overtaking vehicle (19) and an overtaken road user (20) in measured values generated by the measurement system (2), an estimation unit (4) which is designed to determine distances (a) between objects in the detection area (7), a comparator (5) which is designed to compare distances (a) between objects in the detection area (7) determined by the estimation unit (4) with a minimum distance (8) and to generate and output a trigger event based thereon, and a display and / or detection unit (6) which is designed to perform an action based on the trigger event.

2. The traffic monitoring system according to claim 1, wherein the evaluation unit (3) is designed to identify objects on the basis of their dimension and / or their position in the detection area (7).

3. The traffic monitoring system according to claim 1 or 2, wherein the evaluation unit (3) is based on an AI - artificial intelligence - approach.

4. The traffic monitoring system according to any one of claims 1 to 3, wherein the measurement system (2) comprises a camera, the image of which can be used by the evaluation unit (3) when identifying objects in the detection area (7).

5. The traffic monitoring system according to any one of claims 1 to 4, wherein the measured values of the measurement system (2) comprise information about distances (aA, aF) between the measurement system (2) and detected objects in the detection area (7), and wherein the evaluation unit (4) is designed to determine the distances (aA, aF) between objects in the detection area (7) on the basis of distances (a) between the measurement system (2) and detected objects in the detection area (7).

6. The traffic monitoring system according to claim 5, wherein the evaluation unit (4) is designed to determine the distances (a) between objects in the detection area (7) as the difference of distances (aA, aF) between the measurement system (2) and detected objects in the detection area (7).

7. The traffic monitoring system according to any one of claims 1 to 6, wherein the evaluation unit (4), when it determines the distances (a) between objects in the detection area, is designed to use reference points and / or reference lines (17, 18, 19) in measured values of the measurement system (2) and / or a time course within the measured values of the measurement system (2).

8. The traffic monitoring system according to any one of claims 1 to 7, wherein the measurement system (2) comprises a radar system, a ToF - time of flight - camera, a stereo camera or a LIDAR - laser imaging detection and ranging - system.

9. The traffic monitoring system according to any one of claims 1 to 8, wherein the measurement system (2) is arranged relative to a monitored carriageway (14) in such a way that at least one plane within the detection area (7) of the measurement system (2) is arranged perpendicular to the carriageway (14).

10. The traffic monitoring system according to any one of claims 1 to 9, wherein at least the measurement system (2) and the display and / or detection unit (6) are spatially separated from one another, wherein the display and / or detection unit (6) receives the trigger event, or the measurement system (2), the evaluation unit (3), the estimation unit (4), the comparator (5) and the display and / or detection unit (6) are arranged in a common housing.

11. The traffic monitoring system according to any one of claims 1 to 10, wherein the display and / or detection unit (6) is designed to output light characters (9) on the basis of the trigger event.

12. The traffic monitoring system according to any one of claims 1 to 11, wherein the display and / or detection unit (6) is designed to generate a photograph and / or a video by means of a camera (10) on the basis of the trigger event, which documents an overtaking procedure of the overtaken road user by the overtaking vehicle.

13. The traffic monitoring system according to any one of claims 1 to 12, additionally comprising a logging unit, wherein the logging unit is communicatively connected to the measurement system (2), the evaluation unit (3), the estimation unit (4) and / or the comparator (5), wherein the logging unit is designed to store and / or evaluate events detected by the traffic monitoring system.

14. The traffic monitoring system according to any one of claims 1 to 13, additionally comprising a communication unit (13), wherein the communication unit (13) is designed to communicate trigger events and / or recorded photos and / or recorded videos and / or measured values to a control point and / or a logging unit.

15. A method for monitoring a lateral distance between an overtaking vehicle (19) and an overtaken road user (20), comprising: generating measured values by means of a stationary measurement system (2), wherein the measured values represent moving objects in a detection area (7) of the measurement system (2), identifying objects in the detection area (7) as an overtaking vehicle (19) and / or an overtaken road user (20) based on the measured values, determining distances (a) between objects in the detection area (7), comparing determined distances (a) between objects in the detection area (7) with a minimum distance (8), generating and outputting a trigger event based on the comparison of determined distances (a) with the minimum distance (8), and performing an action by a display and / or detection unit (6) based on the trigger event.