VEHICLE GUIDANCE PROCEDURES FOR SITUATIONS WITH LIMITED VISIBILITY DUE TO WEATHER CONDITIONS

Abstract

 The invention relates to a vehicle guidance method for situations with visibility limitation due to weather conditions, the vehicle guidance method being executable by an ego motor vehicle, the vehicle guidance method comprising at least the following steps in the order mentioned, which are communicated between the on-board computer and a cloud system via the telematics device:
a. using the on-board computer, maintaining a data exchange with a weather service in a cloud system;
b. by the on-board computer or the weather service, in the event of a current weather-related situation with visibility restriction, checking whether it is relevant for the ego motor vehicle;
c. by the weather service, if the visibility restriction is determined to be relevant, transmitting an indication of the current presence of a visibility restriction situation; and
d. from the on-board computer, issuing a command to the propulsion system to move into defensive driving mode.
The vehicle guidance system enables safe driving in the presence of a severe visibility restriction.

Description

[0001] The invention relates to a vehicle guidance method for situations with visibility restriction due to weather conditions, a motor vehicle on which such a vehicle guidance method is executable, a computer program and a computer program product with such a vehicle guidance method.

[0002] It is known to support vehicle drivers in individual traffic, especially in critical situations. This ranges from brake assistance to fully autonomous driving. Here, a vehicle guidance method is proposed that provides support in poor visibility conditions. In fog or heavy rain, visibility for a vehicle driver is so limited that normal driving at an otherwise appropriate speed is no longer possible. Such events can occur very suddenly and/or locally without any warning that can be perceived by the driver's senses.

[0003] On this basis, the present invention is based on the task of at least partially overcoming the disadvantages known from the prior art. The features according to the invention result from the independent claims, for which advantageous embodiments are shown in the dependent claims. The features of the claims can be combined in any technically sensible manner, whereby the explanations from the following description as well as features from the figures, which comprise supplementary embodiments of the invention, can also be used for this purpose.

[0004] The invention relates to a vehicle guidance method for situations with visibility limitation due to weather conditions, the vehicle guidance method being executable by an ego motor vehicle, the ego motor vehicle comprising at least the following components:

• a drive entity for propelling and steering the ego motor vehicle;
• an on-board computer configured to communicate with the drive entity of the ego motor vehicle and to perform autonomous driving; and
• a telematics device configured to locate the ego motor vehicle and to communicate wirelessly with a cloud system,

the telematics device being communicatively connected to the on-board computer, and
wherein the vehicle guidance method comprises at least the following steps in the order named, communicated via the telematics device between the on-board computer and a cloud system:

a. using the on-board computer, maintaining a data exchange with a weather service in a cloud system;

b. by the on-board computer or the weather service, in the event of a current weather-related situation with visibility restriction, checking whether it is relevant for the ego motor vehicle;

c. by the weather service, if the visibility restriction is determined to be relevant, transmitting an indication of the current existence of a visibility-restricted situation; and

d. from the on-board computer, issuing a command to the drive entity to move into defensive driving mode.

[0005] Unless explicitly stated to the contrary, ordinal numbers used in the preceding and following descriptions are for the purpose of clear distinction only and do not reflect any order or ranking of the designated components. An ordinal number greater than one does not imply that another such component must necessarily be present.

[0006] The vehicle guidance method proposed here is designed in communication with a cloud system that guides a weather service, whereupon the drive entity of the motor vehicle is taken over by an on-board computer in fully autonomous driving. It should be noted that, for the sake of simplicity, the term drive entity here includes both the drive machine and the steering device, which are necessary for the purposeful driving of a motor vehicle. In a concrete application, such a drive entity is highly complex and also comprises (at least in communication with it) a multitude of sensors and control units, for example an engine control, a brake assistance, a tyre pressure monitoring, distance sensors and many more. The on-board computer is not or at least not exclusively a simple classic on-board computer, but configured for fully autonomous driving. An ordinary on-board computer is thus configured with high computing power and a highly complex control system. In its simplest form, the telematics device is configured for wireless communication, for example via WLAN [Wireless Local Area Network], PAN [Personal Area Network] or mobile radio (for example according to a current GSMA standard, preferably 5G). Furthermore, the telematics device is configured to locate the ego motor vehicle, for example via a geolocation device (e.g., GPS, Galileo or BeiDou) and/or triangulation, for example as part of a mobile radio communication. Alternatively or supportively, a sensor system for (h)odometry can also be used.

[0007] The weather service in a cloud system is a sovereign provider, a private provider and/or a proprietary provider, which is configured to provide information about weather data and, above all, dangers due to specific weather events. For example, such weather data or weather information is used for navigation in a motor vehicle navigation system.

[0008] A situation of restricted visibility is at least a situation in which a person's vision is reduced i.e., the range of vision and/or the contrasts are restricted compared to normal conditions. Preferably, the visibility restriction is to be classified as severe, for example in such a way that continuing the journey without the assistance of a human being is not possible or at least not sufficiently safe or is assessed (by the cloud system and/or the on-board computer of the ego motor vehicle) as unsafe. In one embodiment, such a situation of restricted visibility only or already exists if one or all of the vision sensors of an ego-driven vehicle are also restricted in their performance. This is, for example, different for infrared sensors from the situations for the human eye. It should be noted that rain, for example, is significantly more limiting for such vision sensors for their own performance than for human perception.

[0009] The ego motor vehicle is a motor vehicle that is currently being considered and configured to perform the vehicle control procedure. In an execution of the vehicle guidance method from the perspective of the cloud system, a large number of such ego motor vehicles are present.

[0010] In the data exchange (according to step a.) with a weather service in a cloud system, the ego motor vehicle receives an indication of a current weather event with relevance for the ego vehicle in the event of the vehicle guidance method proposed here becoming active in step c. Relevance for the ego vehicle is present if a trajectory (planned navigation trajectory or trajectory to be driven with high probability due to road guidance) of the ego motor vehicle crosses the region in which the weather event occurs. For example, a currently or planned road traverses a valley in which a low fog field hangs. This is checked in step b. In one embodiment, step b. is configured exclusively by the cloud system to which the trajectory of the ego vehicle has been or will be communicated. In one embodiment, step b. is configured exclusively by the on-board computer of the ego motor vehicle, so that a trajectory of the ego motor vehicle does not need to be communicated to the cloud system. Alternatively, both are configured and/or supported by another cloud system independent of the weather service. It should be noted that the indication according to step c. is communicated to the ego motor vehicle even if there is no relevance, provided that the on-board computer should or must decide on the relevance.

[0011] The drive entity assumes a defensive driving on the command according to step d. if the indication in step c. has been received. A defensive driving is such a driving mode in which the danger to the ego motor vehicle, but also and above all to other road users, is reduced, at least compared to a normal driving mode in the affected region with the current (relevant) weather event causing the visibility restriction situation. Defensive driving includes driving slowly, refraining from overtaking manoeuvres, increasing a distance to a vehicle in front, reducing the maximum steering angle, avoiding lane changes, increasing the receptacle of communication with other road users (for example using the cloud system and/or as vehicle-to-vehicle communication, for example as so-called V2V communication or including other participants V2X communication).

[0012] Thus, dangers in the situation of limited visibility are significantly reduced compared to normal driving. It should be noted that defensive driving is preferably always configured fully autonomously.

[0013] It is further proposed in an advantageous embodiment of the vehicle guidance method that, in order to assume defensive driving, at least one of the following steps is configured by the on-board computer:

• issuing a command to the drive entity to move into a convoy;
• using a position monitor, checking in which lane of a road currently being travelled on the ego motor vehicle is located and, if necessary, issuing a command to the drive entity to change to a safe lane of the road; and
• with the aid of a distance monitor, regulating a speed and a distance to a vehicle driving in front while maintaining a safety distance, preferably within visual range under the current visual restriction; and
• with the aid of a visual sensor, checking whether the ego motor vehicle is in a situation of visual restriction and, if this is not the case, cancelling the command to the drive entity to move into defensive driving.

[0014] A convoy is a group of vehicles driving behind each other with the distance control set. Often the speed, but also the distance between the vehicles involved is reduced. A convoy has the advantage that (safe) distances between vehicles can be adjusted well, especially adapted to the current visibility restriction. In one embodiment, the convoy is configured exclusively using direct communication between the vehicles involved in the convoy. In one embodiment, the convoy is supported or configured by the cloud system, whereby preferably the distance and/or the speed of the respective vehicle is used for the concrete implementation e.g., distance control. It should be noted that under certain circumstances a higher speed is driven than is recommended for the visibility restriction, for example in order to be able to maintain a convoy in adaptation to other road users.

[0015] The safe lane is a lane of the road, which is statistically and/or currently determined to be the safest or one of a plurality of safest lanes of the present road. In one case, the safe lane is the outermost e.g., the rightmost lane for right-hand traffic. Therefore, as a result of changing to or not leaving the safe lane, a free passage is formed so that road users who have not been adequately warned can take a safe lane and any oncoming vehicles can enter this cleared (opposite) lane with reduced risk when taking evasive action. This also creates an emergency lane. Another reason is to increase the density of vehicles in the safe lane of the road, so that a convoy can be carried out with very small distances.

[0016] The position monitoring is configured using radar sensors, visual sensors, navigation systems and/or (h)odometry. Alternatively or additionally, position monitoring is carried out or supported using vehicle-to-vehicle communication or V2X communication.

[0017] Distance monitoring is configured using radar sensors and/or visual sensors. Alternatively or additionally, the position monitoring is carried out or supported using vehicle-to-vehicle communication or V2X communication. Furthermore, the navigation system and/or (h)odometry may also be used for support.

[0018] In one embodiment, a safety distance is a fixed value. Alternatively or additionally, the safety distance is dependent on a plurality of conditions, for example, road conditions, current speed, tyre pressure, visibility restriction (responsiveness), type of vehicle ahead (longer or shorter expected stopping distance) and/or weight of the ego motor vehicle in question. The visibility range is that of the vehicle driver (estimated, for example determined by the cloud system weather service) or the vision sensors (measured or estimated), preferably the greater of the two. It should be noted that maintaining a safe distance comprises, in particular, speed control and, more specifically, depending on the current behaviour of the vehicle in front. In an advantageous embodiment, the behaviour of a plurality of vehicles or at least the foremost vehicle in a convoy is monitored using the cloud system and/or V2V communication or V2X communication for distance monitoring, so that a reaction (e.g., deceleration) is not only triggered by an acute reduction in the distance to the vehicle in front, but a reaction can already be taken in advance. A build-up of vehicle movements can thus be efficiently prevented.

[0019] It is well known that information from a weather service is not always up to date or even locally precise enough. Therefore, it is advantageous to check the information from the weather service with the help of at least one visual sensor. If such a situation of visibility restriction does not exist, interventions in the driving behaviour can be refused or at least reduced. For example, in a semi-autonomous journey, only a warning is issued to the vehicle driver. Alternatively, a maximum permissible speed is reduced as long as such a warning is available from the weather service. Alternatively, further measures are taken, for example as mentioned above, which result in a defensive driving or at least a more defensive behaviour of the ego motor vehicle.

[0020] It is further proposed in an advantageous embodiment of the vehicle guidance method that during defensive driving the ego motor vehicle shares its current position including the road lane currently being travelled on with the cloud system, wherein the cloud system manages the position of the plurality of communicating vehicles depending on the current positions of these vehicles,
wherein preferably depending on the positions and/or amount of managed vehicles the cloud system sets speed, distance and/or lane to be travelled on by the managed vehicles.

[0021] In this embodiment, the plurality of vehicles being in active communication with the cloud system and e.g., the weather service as the algorithm to carry out the management, are positioned by the cloud system. For example, the respective vehicle's on-board computer would not have decided to make a change of lane, speed or distance or would have (based on it's sensors) decided differently in this regard. However, in this method the order from the cloud system wins over the vehicle's own decision. However, preferably still the respective vehicles inhere the possibility of changing the lane, speed and distance due to sensor data from it's own sensors e.g., if a minimal safety distance limit is trespassed or about to be trespassed. Another reason might be a defect in the respective vehicle or (e.g., suddenly occurring change to) severely worse weather conditions than being the assumption basis of the weather service.

[0022] It is further proposed in an advantageous embodiment of the vehicle guidance method that during semi-autonomous driving with the ego motor vehicle, taking over from the on-board computer and fully autonomous driving with the ego motor vehicle in order to take over the defensive driving or to configure it meanwhile, whereby preferably after the end of the situation of visibility restriction the termination of the fully autonomous driving is offered to a vehicle driver of the ego motor vehicle.

[0023] In this embodiment, defensive driving is taken over by the on-board computer in fully autonomous driving in a relevant situation of restricted visibility. In one embodiment, this takeover by the on-board computer already takes place before the defensive driving is assumed i.e., already the initiation or transition to the defensive driving. In one embodiment, the vehicle driver must first initiate or transfer to defensive driving and the on-board computer does not take over until defensive driving (parameters) is reached. In one embodiment, the takeover by the on-board computer is optional, if necessary, also with regard to the time of the takeover in this process. In one embodiment, the takeover is forced. In one embodiment, the vehicle driver is offered at least one alternative to the takeover by the on-board computer (fully autonomous), such as taking up a parking position or maintaining a maximum speed.

[0024] In an advantageous embodiment, after the end of the visibility restriction situation, the offer is issued for the vehicle driver to take over (or more of) control of the ego motor vehicle again i.e., the end of the fully autonomous journey. In one embodiment, if the vehicle driver fails to take over, the journey is continued in a fully autonomous mode or a parking situation is assumed. The latter, for example, if in the current (subsequent) situation a fully autonomous journey is not deemed to be sufficiently safe.

[0025] In an advantageous embodiment of the vehicle guidance method, it is further proposed that the telematics device uses the on-board computer in vehicle-to-vehicle communication with at least one, preferably all, vehicles in the current ego environment to query whether this at least one vehicle is in a convoy.

[0026] Here, it is suggested that a convoy can be detected, and a convoy is not formed with a vehicle that is (possibly) not in a safe driving mode. If necessary, a vehicle in the ego environment of the ego motor vehicle is automatically categorised as an obstacle or as a hazardous situation and a correspondingly higher distance to this non-communicating vehicle is maintained. As a basis for this, if this is not possible with the distance monitoring of the ego vehicle due to the desired distance and the current visibility restriction or visibility range, support is provided using a trajectory estimation for the non-communicating vehicle. The trajectory estimation is configured or supported, for example, by the on-board computer, a vehicle-to-vehicle communication or V2X communication (preferably using swarm intelligence) or a cloud system.

[0027] It is further proposed in an advantageous embodiment of the vehicle guidance method that the ego motor vehicle negotiates with the at least one interrogated other vehicle in the convoy before assuming a position in the convoy where and/or how the ego motor vehicle assumes its position in the convoy.

[0028] Here it is suggested that a convoy is not left solely to the sensor system or a distance monitoring system, but negotiated on a communication path when vehicle-to-vehicle communication is possible. This opens up possibilities for a more efficient and/or smoother integration into an existing or to be formed convoy. The distance monitoring system is preferably active in a supporting or configuring capacity when implementing the result of the negotiation.

[0029] It is further proposed in an advantageous embodiment of the vehicle guidance method that the ego motor vehicle and the at least one interrogated other vehicle in a convoy share action instructions with each other in case of and/or warn of:

• an obstacle;
• a hazardous situation;
• a non-communicating vehicle; and/or
• detection of the beginning and/or end of the current visibility restriction situation.

[0030] Here, a swarm driving mode within the convoy is suggested, whereby the individual distance monitoring of the vehicles involved in the convoy does not (alone) regulate the distances. As described above, this can lead to a build-up of speeds and distances. Instead, the situations known to the other (communicating) vehicles are shared with the others. Preferably, one's own (planned) action (e.g., deceleration or stop) and/or a recommendation for action is also passed on.

[0031] In one embodiment, the aspect that the ego motor vehicle itself checks whether the visibility restriction situation is actually relevant or present is supplemented by the fact that another (communicating) vehicle in or leaving the convoy indicates the end of the visibility restriction situation. Conversely, however, the beginning of the visibility restriction situation is also communicated to the other (communicating) vehicles (especially in the case of a deviation from the information from the weather service). For this purpose, it is intended, for example, that the vehicles capable of communication communicate with each other before entering the region with restricted visibility and coordinate with each other in the swarm without having to adopt a defensive driving position.

[0032] According to a further aspect, a motor vehicle is proposed comprising at least the following components:

• a drive entity having at least one propulsion wheel, having at least one drive machine and a deceleration device for accelerating the motor vehicle using the at least one propulsion wheel, and having a steering device for steering the motor vehicle;
• an on-board computer configured to communicate with the propulsion system of the ego motor vehicle and to perform autonomous driving;
• a telematics device for locating the motor vehicle and for wireless communication with a cloud system, the telematics device being communicatively connected to the on-board computer; and
• a sensor system for sensing the ego environment,

wherein the on-board computer is configured to execute the vehicle guidance method according to an embodiment according to the above description and, following this, to issue recommendations and/or commands for accelerating the motor vehicle and/or for controlling the drive machine and the deceleration device.

[0033] The motor vehicle is a possible ego motor vehicle for the vehicle guidance method described above. For this purpose, the motor vehicle has a drive entity, which comprises at least one drive machine and a steering device. The motor vehicle is configured for fully autonomous driving using the corresponding on-board computer, but can preferably also be driven semi-autonomously. It can be driven by means of one or more propulsion wheels of the drive entity, whereby an on-board computer is able to intervene in the driving action by using a recommendation to a vehicle driver and/or by using direct control. The drive machine is, for example, an internal combustion engine and/or an electric traction engine. The deceleration device is a braking device, a recuperation device and/or a parking brake. Reference is made to the preceding description with reference to the vehicle control method at least as one possible embodiment, insofar as this relates to the motor vehicle and its components. An on-board computer with processor and data memory is configured conventionally, for example, and reference is made to the following description, especially to the figures.

[0034] A telematics device is configured to communicate wirelessly with cloud services (via a mobile network or cellular communication network) or with other vehicles in the vicinity (direct vehicle-to-vehicle communication via a V2X standard), as explained above. In many cases, the cellular communication networks are operated according to the 3GPP suite of radio access technologies, such as 2G-GSM, 3G-UMTS, 4G-LTE, 5G-NR (or an upcoming successor technology) used for data transmission. Because a telematics device is carried on board a motor vehicle, it can collect telemetry data from the motor vehicle, such as (its) position, speed, engine data, connection quality and/or more, by interfacing (for example, via data buses and/or control buses) with various subsystems in the motor vehicle. In general, all data collected throughout the motor vehicle and processed by the telematics device can be considered sensor data.

[0035] In addition, the telematics device can offer the vehicle driver and/or passengers connectivity in the motor vehicle via wireless connection, for example using WLAN [wireless local area network] and/or PAN [personal area network]. The eCall function required in many markets (use of the vehicle's internal voice systems in connectivity with a mobile phone, for example a so-called smartphone) can also be implemented by the telematics device.

[0036] The sensor system today is comprehensive and complex. For the vehicle guidance method, special mention should be made here of the vision sensors, such as a so-called LIDaR [Light Imaging, Detection and Ranging] and/or cameras, which operate in or near the light spectrum visible to humans. Furthermore, radar sensors. But also acceleration sensors, gyroscopes, (h)odometers, steering angle meters, engine control, and many more can at least be used within the framework of the vehicle control system.

[0037] In one embodiment, the on-board computer is a classic centrally located computer unit. Alternatively or additionally, decentralised computers, microprocessors, microcontrollers, and similar units are provided and perform, for example, subtasks.

[0038] According to a further aspect, a computer program is proposed comprising
a computer program code, the computer program code being executable on at least one computer such that the at least one computer is caused to configure the vehicle guidance method according to an embodiment according to the above description, wherein at least one unit of the computer:

• is arranged in an on-board computer of a motor vehicle, preferably according to an embodiment according to the above description; and/or
• is arranged to communicate with a cloud system on which preferably at least part of the computer program code is provided.

[0039] The computer-implemented (vehicle guidance) method is realised, for example, by a computer program, the computer program comprising computer program code, the computer program code, when executed on a computer, causing the computer to configure the method according to an embodiment according to the preceding description. Computer program code is synonymously one or more instructions or commands that cause a computer to perform a series of operations representing, for example, an algorithm and/or other processing methods.

[0040] The computer program is preferably partially or completely executable on an on-board computer and/or on a server or server unit of a so-called cloud or cloud system, a handheld (for example a smartphone) and/or on at least one unit of the computer. The term server or server unit is used here to refer to such a computer which provides data and/or operational services or services for one or more other computer-based devices or computers and thus forms the cloud system. Preferably, the computer on board a motor vehicle is able to configure the computer program independently without using further resources and thus to provide the data for real-time operations in a short and (transmission) secure way for downstream control procedures as input values, for example for collision avoidance of the ego motor vehicle with another vehicle and/or for increasing the efficiency of the driving behaviour of the ego motor vehicle in heavy traffic.

[0041] Terms cloud (system) or computer are used here synonymously with the devices known from the prior art. Accordingly, a computer comprises one or more general purpose processors (CPU) or microprocessors, RISC processors, GPU and/or DSP. The computer has, for example, additional elements such as memory interfaces or communication interfaces. Optionally or additionally, the terms denote such a device capable of configuring a provided or embedded program, preferably using standardised programming language (for example C++, JavaScript, or Python) and/or controlling and/or accessing data storage devices and/or other devices such as input interfaces and output interfaces. The term computer also refers to a plurality of processors or a plurality of (sub-) computers which are interconnected and/or otherwise communicating with each other via physical lines and may share one or more other resources, such as a data memory. A (data) memory is, for example, a hard disk drive (HDD) or a solid state (non-volatile) memory, for example a ROM memory or flash memory [Flash EEPROM]. The memory often comprises a plurality of individual physical units or is distributed across a number of separate devices so that access to it takes place via data communication, for example package data service. The latter is a decentralised solution, whereby the memory and processors of a large number of separate computers are used instead of or in addition to a (single) central server.

[0042] According to a further aspect, a computer program product is proposed on which
a computer program code is stored, the computer program code being executable on at least one computer such that the at least one computer is caused to configure the vehicle guidance method according to an embodiment according to the above description, wherein at least one unit of the computer:

• is arranged in an on-board computer of a motor vehicle, preferably according to an embodiment according to the above description; and/or
• is arranged to communicate with a cloud system on which preferably at least part of the computer program code is provided.

[0043] A computer program product comprising the computer program code described above is, for example, a medium such as RAM, ROM, an SD card, a memory card, a flash memory card, or a disc, or stored on a server and downloadable. Once the computer program is made readable via a readout unit, for example a drive and/or an installation, the computer program code contained therein and the method for segmenting objects with proper motion contained therein is executable by a computer or in communication with a plurality of server units, for example as described above.

[0044] In one aspect of the invention, preferably in case that all vehicles are communicating with the cloud system hosting the weather service:

1) the weather service of the cloud system discovers an upcoming fog or other visibility restricting condition and sends all communicating vehicles in that particular area a signal with a start and end position of the fog (or the like) to move to a safe (e.g., right) lane, if they are on another (e.g., the left) lane. The vehicles will be also warned and asked to be prepared for an full-autonomous defensive driving for a fog trip:

2) the autonomous system will be enabled by the cloud system in the communicating vehicles and drive in a convoy will be enabled with a determined Distance D. This is made use of Adaptive Cruise Control [ACC], lane system to avoid crashes in low visibility weather conditions. These vehicles drive now at reduced speed with determined distance D to neighboring vehicle(s). The weather service of the cloud system knows start and end point, how many (communicating) vehicles are driving in the particular area, and at which distance D to each other.

3) As convoy driving is enabled, the communicating vehicles will be driven full-autonomously at a determined speed through the fog area, controlled by the weather service of the cloud system. Finally, the weather service enables a safe journey to avoid death and crash.

[0045] The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, it being noted that the drawings are not dimensionally accurate and are not suitable for defining dimensional relationships. It is illustrated in:

Fig. 1:

schematic of a plurality of motor vehicles with convoy driving in communication with a weather service in a cloud system;

Fig. 2:

schematic of a motor vehicle with on-board computer, drive entity and sensor system; and

Fig. 3:

a diagram of a sequence of the vehicle guidance procedure.

[0046] Fig. 1 schematically shows a plurality of motor vehicles 1 driving in convoy on a road 9 in communication with a weather service in a cloud system 5. On the safe (here outermost or rightmost) lane 8 of the road (in this case the uppermost lane) there are, purely representatively, four vehicles 12 travelling in a convoy with a distance 11 from each other or from the vehicle 12 in front regulated using a distance monitoring system 10. Furthermore, two vehicles 12, one of which is referred to here by way of example as the ego motor vehicle 1 under consideration, want to join the convoy. A further vehicle 13 is not connected to the weather service of the cloud system 5 and, moreover, is not in communicating connection with the other vehicles 12. The other vehicles 12 communicate with at least one of the other communicating vehicles 12, for example at least with the vehicle 12 in front in each case. The (purely representative two) vehicles 12 in the road-inner lane 7 of the road not only want to join the convoy, but also or alternatively want to change solely to the safe lane 8 of the road. In doing so, the respective sensor system 22 detects the other vehicles 12,13 or is preferably in indirect (for example via the cloud system 5) or direct (for example as vehicle-to-vehicle communication) communication with them. The ego motor vehicle 1 (as well as, purely optionally, the other communicating vehicles 12) is here in direct communicating connection with the cloud system 5 and receives from the weather service a (possibly relevant) indication of a situation of visibility restriction on its anticipated (for example planned) trajectory. For example, in the scene shown, the entire road 9 is in a fog field 25. For a vehicle driver in the ego motor vehicle 1, the other vehicles 12,13 that are clearly visible under normal conditions in the ego environment 17 (with a high degree of probability according to the assessment of the weather service and/or the e.g., own visual sensors 16) are not or only insufficiently visible. Defensive driving is therefore to be adopted for the ego motor vehicle 1. Driving in a convoy is shown here as an example. In this convoy, the distance 11 is to be set, preferably between a minimum safety distance 14 and a visibility range 15 in the current situation of restricted visibility. This is regulated by the own distance monitoring 10 using corresponding control of the own speed.

[0047] Fig. 2 schematically shows a motor vehicle 1 with on-board computer 3, drive entity 2 and sensor system 22. The drive entity 2 comprises a drive machine 19 (for example an electric traction machine), a deceleration device 20 (here exemplified by a brake disc) and a steering device 21 (here symbolised by a steering rod and steering wheel) and a propulsion wheel 18 (here purely optional on the front axle). The sensor system 22 comprises a position monitor 6 (here exemplarily satellite-based, symbolised by a satellite dish), a vision sensor 16 (here exemplarily a camera) and a distance monitor 10 (for example a LIDaR or radar). The on-board computer 3 is represented here by a CPU and a data memory and the telematics device 4 by a SIM card, as used in mobile telephony. A visibility range 15 is also indicated here, which here symbolically extends to a fog field 25.

[0048] Fig. 3 shows a diagram of a sequence of the vehicle control process. A cloud system 5 is shown on the left of the diagram and an ego motor vehicle 1 with an on-board computer 3 is shown on the right, which is in communication with a logic 24 for processing weather data 23 from the weather service of the cloud system 5. This logic 24 is shown disassembled here, but preferably configured in a physical component of the on-board computer 3.

[0049] First, weather data 23 arrives in the cloud system 5 and it is determined (ii) whether it is a visibility restriction situation. If applicable, it is already determined for which vehicles this information is relevant and/or, if applicable, one or a plurality of commands (ii) are already issued. Such a command is, for example, a lane change, assumption of a convoy, limitation of the maximum speed or a specific speed or a speed window. Furthermore, the cloud system 5 outputs the (local and/or temporal) beginning and end of the visibility restriction situation. The on-board computer 3 passes this information (based on the weather data 23) and, if necessary, commands (iii) to the logic 24. There, in this example, it is checked (iv) whether the ego motor vehicle 1 is already in the safe lane 8 of the road and, if necessary, (v) changed to the safe lane 8 of the road and outputs its (new) position (vi). The ego motor vehicle 1 also prefers (vii) to pass on its position and the lane 8 currently being travelled in to the cloud system 5 so that the calculations for driving in a convoy (ix) are configured there after the position (viii) has been checked. For this purpose, the speed and distance 11 to a vehicle 12,13 travelling ahead are calculated and sent (x). Alternatively or additionally, this is configured by the on-board computer 3 and/or negotiated in a swarm intelligence with the other communicating vehicles 12. The logic 24 implements the commands (xi) of the cloud system, in this case, for example, taking the convoy (xiii) with a predetermined speed and distance 11 (xii). The vehicle driver is informed of this process and that the ego motor vehicle 1 is now being guided fully autonomously by the on-board computer 3. The own position is now transmitted to the cloud system 5 again, permanently or at short intervals (xiv) and (xv). If the cloud system 5 (or alternatively the ego motor vehicle 1 itself, for example in protection with the communicating connected other vehicles 12 in the ego environment 17) now determines (xiv) that the ego motor vehicle 1 is leaving the situation of limited visibility or the weather event has settled, it gives the command (xvii) to cancel the defensive driving again i.e., to end the driving in a convoy here. The ego motor vehicle 1 implements this command (xviii) i.e., dissolves the convoy (xix), and informs (xx) the vehicle driver that he or she should or can take control again shortly (for example in a semi-autonomous driving mode).

[0050] The invention relates to a vehicle guidance method for situations with visibility limitation due to weather conditions, the vehicle guidance method being executable by an ego motor vehicle, the vehicle guidance method comprising at least the following steps in the order mentioned, which are communicated between the onboard computer and a cloud system via the telematics device:

a. using the on-board computer, maintaining a data exchange with a weather service in a cloud system;

b. by the on-board computer or the weather service, in the event of a current weather-related situation with visibility restriction, checking whether it is relevant for the ego motor vehicle;

c. by the weather service, if the visibility restriction is determined to be relevant, transmitting an indication of the current presence of a visibility restriction situation; and

d. from the on-board computer, issuing a command to the propulsion system to move into defensive driving mode.

[0051] The vehicle guidance system enables safe driving in the presence of a severe visibility restriction.

List of reference signs

[0052] 

1

ego motor vehicle

2

drive entity

3

onboard computer

4

telematics device

5

cloud system

6

position monitoring

7

road-inner lane

8

safe lane

9

road

10

distance monitoring

11

distance

12

communicating vehicle

13

non-communicating vehicle

14

safety distance

15

visibility range

16

vision sensor

17

ego environment

18

propulsion wheel

19

drive machine

20

deceleration device

21

steering device

22

sensor system

23

weather data

24

logic

25

fog field

Claims

1. Vehicle guidance method for situations with visibility restriction due to weather conditions, wherein the vehicle guidance method is executable by an ego motor vehicle (1) and the ego motor vehicle (1) comprises at least the following components:

- a drive entity (2) for propelling and steering the ego motor vehicle (1);

- an on-board computer (3) configured to communicate with the drive entity (2) of the ego motor vehicle (1) and to perform autonomous driving; and

- a telematics device (4) configured to locate the ego motor vehicle (1) and to communicate wirelessly with a cloud system (5),

wherein the telematics device (4) is communicatively connected to the onboard computer (3), and
wherein the vehicle guidance method comprises at least the following steps in the order mentioned, which are communicated via the telematics device (4) between the on-board computer (3) and a cloud system (5):

a. using the on-board computer (3), maintaining a data exchange with a weather service in a cloud system (5);

b. by the on-board computer (3) or the weather service, in the event of a current weather-related situation with visibility restriction, checking whether it is relevant for the ego motor vehicle (1);

c. by the weather service, if the visibility restriction is determined to be relevant, transmitting an indication of the current existence of a visibility-restricted situation; and

d. from the on-board computer (3), issuing a command to the propulsion system (2) to move into defensive driving.

2. The vehicle guidance method according to claim 1, wherein
at least one of the following steps is configured
by the on-board computer (3) for assuming defensive driving:

- outputting a command to the drive entity (2) to move into a convoy;

- using a position monitor (6) to check in which lane (7, 8) of a road (9) currently being travelled on the ego motor vehicle (1) is located and, if necessary, outputting a command to the drive entity (2) to change to a safe lane (8) of the road; and

- with the aid of distance monitoring (10), regulating a speed and a distance (11) to a vehicle (12, 13) travelling in front while maintaining a safety distance (14), preferably within visibility range (15) under the current visibility restriction; and

- with the aid of a vision sensor (16) checking whether the ego motor vehicle (1) is in a situation of visibility restriction and, if this is not the case, cancelling the command to the drive entity (2) to move into defensive driving.

3. The vehicle guidance method according to claim 1 or claim 2, wherein during defensive driving the ego motor vehicle (1) shares its current position including the road lane currently being travelled on with the cloud system (5), wherein the cloud system (5) manages the position of the plurality of communicating vehicles (1,12) depending on the current positions of these vehicles (1,12),
wherein preferably depending on the positions and/or amount of managed vehicles (1,12) the cloud system (5) sets speed, distance and/or lane to be travelled on by the managed vehicles (1,12).

4. The vehicle guidance method according to one of the preceding claims,
wherein

during semi-autonomous driving with the ego motor vehicle (1), taking over from the on-board computer (3) and fully autonomous driving with the ego motor vehicle (1) to take over the defensive driving or to configure it meanwhile,

wherein preferably after the end of the situation of visibility restriction the termination of the fully autonomous driving is offered to a vehicle driver of the ego motor vehicle (1).

5. The vehicle guidance method according to one of the preceding claims,
wherein
the telematics device (4) interrogates, using the on-board computer (3) in vehicle-to-vehicle communication with at least one, preferably all, vehicles (12, 13) located in the current ego environment (17), whether this at least one vehicle (12) is in a convoy.

6. The vehicle guidance method according to claim 5, wherein
the ego motor vehicle (1) negotiates with the at least one interrogated other vehicle (12) in a convoy, before assuming a position in the convoy, where and/or how the ego motor vehicle (1) assumes its position in the convoy.

7. The vehicle guidance method according to claim 5 or claim 6, wherein the ego vehicle (1) and the at least one interrogated other vehicle (12) in line of sight communicate with each other instructions to act upon and/or warn of:

- an obstacle;

- a hazardous situation;

- a non-communicating vehicle (13); and/or

- detection of the beginning and/or end of the current visibility restriction situation.

8. A motor vehicle (1), having at least the following components:

- a drive entity (2) with at least one propulsion wheel (18), with at least one drive machine (19) and a deceleration device (20) for accelerating the motor vehicle (1) using the at least one propulsion wheel (18) and with a steering device (21) for steering the motor vehicle (1);

- an on-board computer (3) configured for communicating with the drive entity (2) of the ego motor vehicle (1) and for carrying out autonomous driving;

- a telematics device (4) for locating the ego motor vehicle (1) and for wirelessly communicating with a cloud system (5), the telematics device (4) being communicatively connected to the on-board computer (3); and

- a sensor system (22) for detecting the ego environment (17), wherein the on-board computer (3) is configured to perform the vehicle guidance method according to one of the preceding claims and subsequently to issue recommendations and/or commands for accelerating the motor vehicle (1) and/or for controlling the drive machine (19) and the deceleration device (20).

9. A computer program comprising
computer program code, the computer program code being executable on at least one computer such that the at least one computer is caused to perform the vehicle guidance method according to any one of claims 1 to 7, wherein at least one unit of the computer:

- is arranged in an on-board computer (3) of a motor vehicle (1), preferably according to claim 8; and/or

- is arranged to communicate with a cloud system (5) on which preferably at least part of the computer program code is provided.

10. A computer program product on which
computer program code is stored, the computer program code being executable on at least one computer in such a way that the at least one computer is caused to execute the vehicle guidance method according to any one of claims 1 to 7, wherein at least one unit of the computer:

- is arranged in an on-board computer (3) of a motor vehicle (1), preferably according to claim 8; and/or

- is configured to communicate with a cloud system (5) on which preferably at least part of the computer program code is provided.

Drawing