Patent Publication Number: US-2021163042-A1

Title: Method for stopping a self-driving vehicle

Description:
RELATED APPLICATIONS 
     The present application claims priority to German Patent Application No. DE 102019218411.1 to van de Klashorst et al., titled “Method for Stopping a Self-Driving Vehicle”, filed Nov. 27, 2019, the contents of which is incorporated by reference in its entirety herein. 
     BACKGROUND 
     The present disclosure relates to a method for stopping a self-driving vehicle, that enables an improved boarding and exiting the vehicle by passengers. A further aspect of the present disclosure relates to a self-driving vehicle configured to execute the technologies and techniques according to the present disclosure. 
     Current vehicles already have numerous assistance systems that assist drivers in a computer-based manner in numerous driving situations. These assistance systems can access sensors for obtaining measurement data that substantially surpasses the sensory capabilities of humans. In addition, the speed of these assistance systems significantly exceeds human reaction times. Known driver assistance systems include, e.g., lane keeping assistance, braking assistance when pedestrians are detected, and adaptive cruise control, in particular in heavy traffic. 
     By using such assistance systems, the autonomy of the driver with respect to driving decisions is increasingly transferred to the vehicle, or these operating control units. The ultimate result of this development will be a self-driving vehicle, which can maneuver entirely without human intervention. Fully automated passenger transportation can be obtained with such a self-driving vehicle. 
     Such self-driving passenger transportation will result in numerous mobility concepts, in particular in urban metropolitan areas. This is based on known ride hailing concepts, in which numerous users access vehicles in a vehicle fleet for limited periods of time, independently of one another. In that the vehicles are only associated with a specific user for the time they are actually in use, the unused time when the vehicle is parked can be minimized. This concept can also be supplemented with so-called ride pooling, in which numerous passengers share a vehicle, at least for parts of the respective route. 
     The concepts have the potential of significantly reducing the total number of necessary vehicles, thus making a positive contribution to environmental protection. 
     With a combination of the aforementioned mobility concepts with self-driving vehicles, in addition to the actual driving tasks other functions become available, without requiring action on the part of a human driver. In addition to storing baggage, directing nonlocal passengers to intermediate and/or target destinations also belong to these functions, as well as enabling a safe boarding and exiting for the passengers. The passengers are no longer assisted by a driver during these procedures, who might first exit the vehicle, for example, to hold the door open for the passengers. As such, the passengers are exposed to greater danger when boarding and exiting. 
     Methods for assisting passengers when boarding and exiting non-self-driving vehicles are known from the prior art, in particular for preventing collisions between other road users and the passengers. A common feature of these methods is that they are executed by a stationary vehicle, or linked to a standstill of the vehicle or its arrival at a target destination. According to these methods, arrival at predetermined target destination is always a prerequisite for executing the remaining steps of the method. 
     The known methods are adequate for conventional vehicles, in which the driver is solely responsible for the decision regarding the actual stopping maneuver. These methods are disadvantageous for self-driving vehicles, however, because they may result in delays in boarding and exiting the vehicle at the target destination. With self-driving automobiles, this may mean that waiting times must be taken into consideration in the overall evaluation of the driving experience, thus potentially reducing customer satisfaction. 
     BRIEF SUMMARY 
     Aspects of the present disclosure are therefore to overcome the disadvantages of the prior art, and provide an improved method for stopping a self-driving vehicle, which minimizes the waiting times for boarding and exiting passengers, thus contributing to the acceptance of self-driving vehicles. 
     Technologies and techniques are disclosed for stopping a self-driving vehicle, comprising determining the approach to a specified stopping point for the vehicle; detecting at least one moving object in an environment of the vehicle; determining a projected trajectory of the vehicle and a projected trajectory of the object at a first point in time t 1 ; determining a second point in time t 2  for the arrival of the vehicle at the specified stopping point based on the projected trajectory of the vehicle, and a position and speed of the object at the second point in time t 2  based on the projected trajectory of the object; determining a collision probability between the object and a door or a passenger of the vehicle at the specified stopping point based on the position and speed of the object at the second point in time t 2 ; and determining a third point in time t 3  for opening at least one door of the vehicle based on the determined collision probability. 
    
    
     
       BREIF DESCRIPTION OF THE DRAWINGS 
       The invention shall be explained below in exemplary embodiments, with reference to the associated drawings. Therein: 
         FIG. 1  shows a schematic illustration of a self-driving motor vehicle according to some aspects of the present disclosure; 
         FIGS. 2 a , 2 b  and 2 c    show schematic illustrations of a self-driving motor vehicle and a further moving object at different points in time according to some aspects of the present disclosure. 
         FIG. 3  shows a schematic illustration of a self-driving motor vehicle and a further moving object at a third point in time according to some aspects of the present disclosure; and 
         FIGS. 4 a  and 4 b    show schematic illustrations of a self-driving motor vehicle and a further moving object at a third and fourth point in time according to some aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In some examples, the present disclosure relates to technologies and techniques for stopping a self-driving vehicle, such as a self-driving motor vehicle, in the semiautomatic or fully automatic transportation of at least one passenger. The method comprises at least the steps described below. In a first step of the method according to the present disclosure, it may be determined that the vehicle may be approaching a specified stopping point for the vehicle. This specified stopping point for the vehicle is preferably a stopping point specified by a passenger of the vehicle. This specified stopping point is preferably input by the user via an input means, e.g. a user interface in the vehicle, or via a mobile end device connected to the vehicle. Furthermore, it is also possible for the user to alter the specified stopping point, even during the stopping procedure. This specified stopping point may also be a stopping point specified by a user who is not yet in the vehicle. This user determines the stopping point, e.g., by inputting it in a mobile end device, wherein this input may be transmitted via a network server for the vehicle. The at least one passenger is preferably located in the vehicle, and would like to exit the vehicle at the specified stop. Alternatively, the at least one passenger may want to board the vehicle at the specified stop. 
     After the initial step, at least one mobile object may be detected in the environment of the vehicle. Self-driving vehicles have numerous sensors for continuously monitoring the environment, e.g. lidar, radar, ultrasound sensors, optical sensors, etc. The distances between the vehicle and surrounding objects are basically continuously determined using these sensors. An identification of the surrounding objects likewise preferably takes place, e.g. through vehicle to vehicle communication or vehicle to X communication, by means of which other mobile vehicles can be distinguished from stationary objects. This object identification also preferably involves algorithms, e.g. based on artificial intelligence (algorithms for machine learning), in order to reliably identify bicyclists, for example, on the basis of their characteristic shape. This therefore represents a simple programming task for the person skilled in the art using the sensors and control units available in a self-driving vehicle for at least detecting a moving object located in the environment of the vehicle. The environment of the vehicle is particularly preferably defined thereby by a distance threshold. This distance threshold is preferably not isotropic in all spatial directions, but instead may be greater in the direction of travel, i.e. along a roadway, than in the lateral direction. 
     In some examples, a projected trajectory of the vehicle and a projected trajectory of the object at a first point in time t 1  are also determined in the method according to the present disclosure. The vehicle uses information regarding the location and speed of the vehicle obtained at numerous points in time to extrapolate the trajectory of the vehicle for this. The vehicle also uses information regarding the location and speed of the object obtained at numerous points in time to extrapolate the trajectory of the object. The determination of the trajectories of vehicles and objects based on numerous measurement values regarding the position and speed of the vehicle/object and the extrapolation of these trajectories into the future, e.g. by means of transverse line methods, is within the abilities of the person skilled in the art. 
     A second time t 2  may be determined on the basis of the determined projected trajectory of the vehicle in the method according to the present disclosure, at which the vehicle arrives at the specified stop. In other words, a specified stopping point may be determined for the vehicle. The position and speed of the object at the second time t 2  may be then determined on the basis of this second point in time t 2  and the determined projected trajectories of the object. In other words, the location and speed of the object may be determined at the specified stopping point for the vehicle. A probability of a collision between the object and a door and/or a passenger of the vehicle at the specified stopping point may be then determined on the basis of the position and speed of the object at the second point in time t 2 . A predefined opening range for the vehicle door and/or a predefined exiting region for a passenger, for example, are also assumed for the position of the vehicle. This opening range and/or exiting region is preferably defined as an arc segment on the exterior of the vehicle. A shortest connection between a position of the vehicle and a nearby footpath, etc. may be determined for a passenger, which comprises the trajectory of the passenger. A collision between an object and a passenger is then preferably defined as an intersection of the trajectory of the object and this arc segment, or an intersection of the trajectories of the object and the pedestrian. 
     A collision probability may be obtained when an intersection of the object trajectory and the arc segment (relating to the door) or an intersection of the trajectories of an object and a pedestrian are determined. Uncertainties in the predicted trajectory of the object in relation to the specified stopping point at time t 2  and relating to the behavior of the passenger are preferably taken into account in determining the collision probability. In other words, these values are varied within predetermined ranges and it may be determined whether one of the intersections defined above applies for each of the varied values. A numerical value may be determined for the risk of a collision between the object and door or passenger based on the number of varied values for which an intersection, i.e. a collision, may be determined. 
     A third time t 3  may be then determined in the vehicle according to the present disclosure based on the determined collision probability, at which at least one door of the vehicle is opened in order to allow a passenger to board or exit. In other words, a time t 3  may be determined at which it is possible to safely board or exit, e.g., without the risk of a collision with the object. In other words, a third time t 3  may be determined at which the collision probability is at a minimum. Such configurations make it possible to already determine a safe point in time for boarding and exiting while a self-driving vehicle is underway. Determination of the point in time while the vehicle is traveling advantageously enables a particularly user-friendly coordination of the boarding and exiting process, as shall be described in greater detail below. In particular, the boarding and exiting can be coordinated such that a passenger will not notice any delays due to a passenger in the interior of the vehicle being unable to open a blocked door. This prevents the passenger for feeling locked in. Furthermore, the time in which the vehicle is stopped, e.g. in no-parking zones, can be advantageously minimized. 
     In some examples, if the collision probability exceeds a predetermined threshold value, a collision between the object and a door or a passenger of the vehicle is probable. According to this embodiment, a third time t 3  is preferably determined that differs from the second time t 2 . In other words, the doors are not opened at the specified stopping time t 2 , but at a different point in time t 3 . The at least one door is preferably opened automatically by a correspondingly regulated mechanism in the self-driving vehicle. Alternatively, the door is opened by outputting the third time t 3  to the passenger, such that the passenger can open the door at this time t 3 . 
     In some examples, an alternative stopping point may be determined within a predetermined tolerance for the specified stopping point. The tolerance is preferably selected such that a passenger or user inside the vehicle, who has called the vehicle, will only have to walk a short distance, and not cross the street. According to this embodiment, the vehicle then stops at the alternative stopping point at the third point in time t 3 . In other words, the determined actual stopping time t 3  according to this embodiment corresponds to a different, alternative stopping point. The alternative stopping point is then preferably sufficiently outside a projected trajectory of the object. This alternative stopping point is also preferably close to a projected trajectory of the object, which is at a distance, however, to the vehicle at the third point in time t 3 , which distance is greater than a predetermined threshold value. In other words, the alternative stopping point is preferably reached by executing an additional steering maneuver. The alternative stopping point is also preferably reached by driving more quickly along the existing trajectory, in order to increase the distance to a slow-moving object. A sufficient exit time for the passenger should be taken into account in increasing the distance to an object. 
     In some examples, the determined collision probability between the vehicle and the object exceeds a threshold value, and the actual third point in time t 3  and the specified second point in time t 2  are identical. According to this embodiment, a collision is prevented exclusively by altering the stopping point, thus stopping at the alternative stopping point. The determined collision probability between the vehicle and the object can also fall below a threshold value, such that the vehicle can stop at the specified stopping point and at the specified point in time, without endangering the passenger/user. 
     In some examples, the speed of the vehicle is adjusted if the collision probability exceeds a threshold value, and the third point in time t 3  and the second point in time t 2  differ. The vehicle also stops at the specified stopping point at the third point in time t 3  according to this preferred embodiment. In other words, the specified stopping point is not altered according to this embodiment, but instead, only the point in time is altered. The vehicle is particularly preferably braked in its trajectory, in order to allow a nearby object to pass by the vehicle. If the user then exits the vehicle at the specified stop, the moving object has already passed, and there is no longer any danger of a collision. It has been shown to be the case that such a stopping behavior is found to be substantially more acceptable by users than stopping at the specified stopping point and locking the doors until the third point in time t 3 ; in particular, the delay in boarding or exiting due to the potential collision with the object is less noticeable. 
     In some examples, a distance between the vehicle and the object at the third point in time t 3  preferably exceeds a predetermined threshold value. This advantageously ensures that even unpredictable acceleration and/or steering maneuvers of the moving object will not result in a collision between the vehicle and the object. Furthermore, a distance between the vehicle and the object has preferably increased at the third point in time t 3 , such that the object has already passed the vehicle at the third point in time t 3 . The aforementioned conditions are likewise preferably already taken into account when determining the third point in time t 3 . 
     A fourth time t 4 , for closing the at least one door of the vehicle is likewise preferably determined in the method according to the present disclosure, wherein this fourth time t 4  is also determined based on the projected trajectory of the moving object. In other words, a time window is determined between the third point in time t 3  and the fourth point in time t 4 , during which it is possible to board or exit the vehicle without the risk of a collision with the object. If, for example, the vehicle is stopped at an alternative stopping point after accelerating the vehicle at time t 3 , which is at a sufficient distance to the object at this time (time t 3 ), this sufficient distance may no longer exist at a fourth point in time t 4 , due to the continued movement of the object. The door must therefore be closed at time t 4 . Furthermore, information regarding the environment with respect to opening and closing the door is preferably provided in a multimodal manner via visual and/or acoustic notifications, as shall be explained in greater detail below. 
     At least one other moving object may also be detected within the environment of the stopping vehicle. The detection of this second object likewise takes place using the numerous sensors and control units built into the vehicle, as explained above. According to this example, a projected trajectory may also be determined for the second object, and the fourth point in time t 4  is determined, alternatively or additionally, on the basis of the projected trajectory of the second object. As such, in a situation in which the distance to a first determined object has already increased at time t 3 , because the vehicle has passed it, there may be a risk posed by a newly arriving moving object. By closing the doors (automatically or manually, after request by a notification) at the fourth point in time t 4 , danger to the passengers from the other object is avoided. 
     In some examples, collision probabilities between the object and each of the numerous doors of the vehicle at the third point in time t 3  are determined. The various doors are defined, e.g., by various arc segments on the outside of the vehicle. An expanded spatial model of the vehicle is also preferably used, by means of which the various doors are defined in various directions by arc segments. According to this embodiment, one of the numerous doors is preferably determined and opened at the third point in time t 3  based on the determined collision probabilities. The selected door is preferably opened automatically by a mechanism for this in the self-driving vehicle, or by the user after a notification has been output to the user. According to this embodiment, boarding or exiting by the user through a particularly endangered door of the vehicle, e.g. facing toward the middle of the road, can preferably be prevented. 
     The number and/or characteristics of passengers of the vehicle is likewise preferably determined using the technologies and techniques described herein. According to some examples, the collision probability between the object and the at least one passenger of the vehicle at the specified stopping point is also determined on the basis of the number and/or characteristics of the passengers. In one example, a longer period of time for boarding and exiting the vehicle is assumed for a larger number of people, and the collision probability is adjusted accordingly (increased). The collision probability is likewise preferably increased for passengers who move slower than average due to injuries or other physical conditions (passengers in wheelchairs, or older, walking-impaired individuals). The same applies for people with children, dogs, or large items, who require more time to board. By taking the number and/or characteristics of passengers into account, the safety of the passengers is further increased when boarding and/or exiting. 
     In some examples, alternatively or additionally to an automatic opening or closing of the vehicle doors, a notification is issued to a passenger of the vehicle. According to one example, this notification may include information regarding the third point in time t 3 , the alternative stopping point, and/or at least one moving object in the environment of the vehicle. This informs the passenger of the maneuvering of the self-driving vehicle as well as dangers posed by other objects. It has been shown to be the case that warning notifications without specific contents are frequently ignored by users. According to this example, notifications relating to specific situations are issued to the passengers, which preferably inform them of the positions and speeds of approaching objects and/or of a safe time window between the points in time t 3  and t 4  for boarding or exiting the vehicle. 
     A number and/or characteristic of at least one passenger or user of the vehicle may also be determined. This characteristic can be, e.g. the age, health, mobility, or nationality of the passenger or user. According to one example, the notification is also preferably adapted on the basis of the number and/or characteristics of the at least one passenger or user. A preferred language may be determined on the basis of a passenger&#39;s input, and the notification is issued in this language accordingly. A visual impairment of a user can likewise be determined, and the notification is then issued acoustically. 
     The notification may be issued via a screen and/or loudspeaker located in the vehicle. This notification informs the passengers of a suitable point in time or timeframe for exiting, as well as approaching objects. The notification is also preferably issued via a screen located on the exterior of the vehicle, or other visual or acoustic interfaces. As a result, users not inside the vehicle can be informed of a suitable point in time, or timeframe, for boarding, as well as of approaching objects. The notification is also preferably projected in an environment of the vehicle to inform a user in the environment of the vehicle who has called the vehicle, for example. 
     The examples provided herein may be implemented by electronic elements or components (hardware), or firmware (ASIC), or realized by executing a suitable program (software). The examples disclosed herein may likewise be realized or implemented by a combination of hardware, firmware, and/or software. Individual components may be configured as separate integrated circuits to execute individual steps, or they are located on a shared integrated circuit. Individual components configured to execute individual steps are also preferably located on a (flexible) printed circuit board (FPCB/PCB), a tape carrier package (TCP), or some other substrate. 
     The individual steps of the methods disclosed herein may be configured as one or more processes that can run on one or more processors in one or more electronic computer devices, and are generated when one or more computer programs are executed. The computers are preferably configured to function with other components, e.g. a communication module and one or more sensors, in order to realize the functions described herein. The instructions of the computer programs are preferably stored in a memory, e.g. a RAM element. The computer programs can also be stored in non-volatile storage mediums, e.g. a flash memory. 
     It should be also clear to the person skilled in the art that the functions of numerous computers (data processing devices) can be combined, or combined in a single device, or that the function of one specific data processing device can be distributed among numerous devices in order to execute the steps of the method without deviating from the method according to the present disclosure described above. 
     Another aspect of the present disclosure relates to a self-driving vehicle, such as a motor vehicle configured for semiautomatic or fully automatic passenger transportation, which is configured to execute the method according to the present disclosure. The motor vehicle may include, but is not limited to, numerous first sensors configured for detecting at least one moving object in the environment of the vehicle. The first sensors may be configured to detect sensor signals relating to the environment of the vehicle. The motor vehicle may also include numerous second sensors for obtaining movement data relating to the vehicle. The second sensors may be configured to detect sensor signals relating to the vehicle itself. The motor vehicle also contains a communication module for communicating with another vehicle and/or mobile end device. The communication module is configured to receive information via a communication network. The communication module preferably contains a radio signal, mobile communications, WLAN, and/or Bluetooth transceiver, or a wireless communication device. The communication module is also preferably configured to receive danger signals from other vehicles in the environment, e.g., via a car-to-car communication network. 
     The motor vehicle according to the present disclosure may also include a first output means for issuing notifications to passengers in the vehicle interior and/or a second output means for issuing notifications to passengers outside the vehicle. The outputting means are preferably a screen, projectors, and/or loudspeakers in the interior and on the exterior of the vehicle. The motor vehicle also contains a driving system configured for autonomous driving of the motor vehicle. The driving system is preferably configured for autonomous lateral and longitudinal control of the vehicle. The motor vehicle also contains a control unit designed and configured to execute the method according to the present disclosure, which is configured in particular to control all of the aforementioned components for executing the method according to the present disclosure. 
     Another aspect of the present disclosure relates to a computer program that includes commands which cause a computer that executes the program, e.g. a control unit in a motor vehicle according to the present disclosure, to execute the method according to the present disclosure, in particular the steps: determining the approach of a specified stopping point for the vehicle; detecting at least one moving object in the environment of the vehicle; determining a projected trajectory of the vehicle and a projected trajectory of the object at a first time t 1 ; determining a second point in time t 2  for the arrival of the vehicle at the specified stopping point based on the projected trajectory of the vehicle, and determining a position and speed of the object at the second point in time t 2  based on the projected trajectory of the object; determining a collision probability between the object and a door or a passenger of the vehicle at the specified stopping point, based on the position and speed of the object at the second point in time t 2 ; and determining a third point in time t 3  for opening at least one door of the vehicle based on the determined collision probability. 
     Another aspect of the present disclosure relates to a computer-readable storage medium, including commands, which cause a computer, e.g. a control unit in a motor vehicle according to the present disclosure, that executes them to execute the method according to the present disclosure, in particular the steps: determining the approach of a specified stopping point for the vehicle; detecting at least one moving object in the environment of the vehicle; determining a projected trajectory of the vehicle and a projected trajectory of the object at a first time t 1 ; determining a second point in time t 2  for the arrival of the vehicle at the specified stopping point, based on the projected trajectory of the vehicle, and a position and speed of the object at the second point in time t 2 , based on the projected trajectory of the object; determining a collision probability between the object and a door or a passenger of the vehicle at the specified stopping point, based on the position and speed of the object at the second point in time t 2 ; and determining a third point in time t 3  for opening at least one door of the vehicle based on the determined collision probability. 
     Further examples of the present disclosure can be derived from the other features specified herein. The various examples of the present disclosures specified in this application can be advantageously combined with one another, as long as not otherwise specified. 
       FIG. 1  shows a schematic diagram, in particular a block diagram of an exemplary self-driving motor vehicle  10  designed for passenger transportation, which includes numerous first sensors, in particular a first sensor  11 , second sensor  12 , and third sensor  13 . The first sensors  11 ,  12 ,  13  may be configured to detect the environment of the vehicle, and in particular objects located in the environment of the vehicle, or the distances between the vehicle and these objects. The first sensors contain, for example, a lidar (sensor  11 ), a radar (sensor  12 ), and an ultrasound sensor (sensor  13 ). The first sensors  11 ,  12 ,  13  transmit the environment signals they record to a control unit  40  in the motor vehicle. 
     The motor vehicle  10  also includes numerous second sensors, in particular a fourth sensor  51 , fifth sensor  52  and sixth sensor  53 . The second sensors  51 ,  52 ,  53  are sensors for determining data relating to the state of the motor vehicle  10  itself, e.g. current position and movement information for the motor vehicle. The second sensors are therefore, e.g., speed sensors, acceleration sensors, tilt sensors, etc. The second sensors  51 ,  52 ,  53  transmit the vehicle state signals they record to the control unit  40  and a driving system  30  in the motor vehicle  10 . 
     The motor vehicle  10  may also include a communication module  20  that contains a loudspeaker  21  and one or more transponders or transceivers  22 . The transponders  22  may include a radio signal, WLAN, GPS, or Bluetooth transceiver, or the like. The transponder communicates with the internal memory  21  in the communication module  20 , e.g. via a suitable data bus. The current position of the motor vehicle  10  can be determined by means of the transponder  22  through communication with a GPS satellite  61 , and store this position in the internal memory  21 . The communication module  20  communicates with the control unit  40 . The communication module  20  may be configured to communicate with network servers, a base station  62 , a mobile communication network, and other (self-driving) vehicles  63 . By way of example, the communication module  20  is configured to communicate with the aforementioned devices via an UMTS or LTE (long term evolution) mobile communication network. 
     The motor vehicle  10  also includes the driving system  30 , which is configured for fully autonomous driving, in particular the longitudinal and lateral control of the motor vehicle  10 . The driving system  30  includes a navigation module  32 , which may be configured to calculate routes between a starting point and a target destination, and to determine the maneuvers that must be executed along these routes by the motor vehicle  10 . The driving system  30  also includes an internal memory  31 , e.g. for map data, which communicates with the navigation module  32 , e.g. via a suitable data bus. At least a portion of the second sensors  51 ,  52 ,  53  in the motor vehicle transmit their results directly to the driving system  30 . The data transmitted directly to the driving system are the current position and movement information for the motor vehicle. These data are preferably obtained from speed sensors, acceleration sensors, tilt sensors, etc. 
     The motor vehicle  10  also includes a control unit  40  according to the present disclosure, which is configured to execute the method according to the present disclosure, as shall be explained in detail below. For this, the control unit  40  has an internal memory  41  and a CPU  42 , which communicate with one another, e.g. via a suitable data bus. Moreover, the control unit is connected for communication to at least the first sensors  11 ,  12 ,  13 , the second sensors  51 ,  52 ,  53 , the communication module  20 , and the driving system  30 , e.g. via one or more respective CAN connections, one or more respective SPI connections, or other suitable data connections. 
     The vehicle  10  also includes an output system  65  for outputting notifications to passengers. The output system  65  contains first output means  66  for outputting notifications to passengers in the vehicle, in particular screens, loudspeakers, and other light signals (e.g. LED light sources). The output system  65  also contains second output means  67  for issuing notifications to passengers outside the vehicle  10 , in particular screens, loudspeakers, and projectors for projecting notifications onto the ground, etc. 
       FIGS. 2( a ) to 2( c )  show schematic illustrations of a self-driving motor vehicle  10  according to some examples, and an additional moving object  70 , at different points in time while the method is being carried out. 
       FIG. 2 a    shows the vehicle  10  according to the present disclosure, and the object  70 , at a first point in time t 1 . At this time, the vehicle  10  and the object  70  are each on a right-hand lane  81  in a fourlane street, which is delimited by a curb  82 . A passenger is conveyed in the vehicle  10 . At the first point in time t 1 , the vehicle has a location x_Fz( 1 ), which has been retrieved from GPS satellites  61  via the communication module, and a speed v_FZ( 1 ), which is determined by the second sensors  51 ,  52 ,  53  and/or by means of the communication module and the GPS satellites  61 . The object has a location x_Ob 1 ( 1 ) and speed v_Ob 1 ( 1 ) at the first point in time t 1 , which are determined by the first sensors  11 ,  12 ,  13  in the vehicle  10 . In addition, the vehicle  10  can use a CAM notification received from the object  70  via car-to-car communication to determine x_Ob 1 ( 1 ) and v_Ob 1 ( 1 ). At the first point in time t 1 , the control unit  40  in the vehicle  10  determines a projected trajectory  84  for the vehicle  10  and a projected trajectory  85  for the object  70  based on the available measurement data and/or communication data. 
     As is shown in  FIG. 2 b   , the second point in time t 2  is determined on the basis of the projected trajectory  84  for the vehicle  10 , at which the vehicle  10  reaches the location x_Fz( 1 ) of a specified stopping point  83 . The specified stopping point  83  corresponds to a target destination for the passengers in the vehicle  10 . The projection of the trajectory  84  for the vehicle  10  is obtained such that the speed of the vehicle  10  v_FZ( 2 ) at the second point in time t 2  is zero, and the vehicle  10  also comes to a stop a the specified stopping point  83 . A position x_Ob 1 ( 2 ) and speed v_Ob 1 ( 2 ) of the object  70  at the second point in time t 2  are also determined on the basis of the projected trajectory  85  for the object  70 . As  FIG. 2 b    shows, the moving object  70 , such as a bicycle, is just behind the vehicle  10  at the second point in time t 2 , with a speed vector that runs along a line between the stopping vehicle  10  and the specified stopping point  83 . The object  70  is therefore in danger of colliding with a door of the vehicle  10  or a passenger getting out of the vehicle  10 . This can be determined on the basis of the position and speed of the object  70  at the second point in time t 2 . 
     Because of the existing collision probability between the object  70  and the vehicle  10  at the specified stopping point  83  at the second point in time t 2 , a third point in time t 3  is determined according to the present disclosure. This third point in time t 3  is determined on the basis of the collision probability such that a door of the vehicle  10  can be safely opened, and a passenger can safely exit the vehicle  10 . According to the situation shown in  FIG. 2 c   , the third point in time t 3  follows the second point in time t 2 , and the vehicle  10  comes to a standstill at a speed v_FZ( 3 ) of zero at the specified stopping point  83  x_Fz( 3 ). The self-driving vehicle  10  has therefore slowed down after the determination of the collision probability, such that the object  70  has enough time to pass by the vehicle  10 . In particular, the object  70  may be located at a position x_Ob 1 ( 3 ) at the third point in time t 3  with a speed vector v_Ob 1 ( 3 ) leading away from the vehicle  10 . The distance between the object  70  and the vehicle is therefore already greater at the third point in time t 3 . The door  15  of the vehicle  10  can therefore be opened, without the threat of a collision with the object  70 . 
       FIG. 3  shows a schematic illustration of the self-driving motor vehicle  10  and the other moving object  70  at the third point in time t 3 ′ according to an alternative embodiment of the method according to the present disclosure. An existing collision probability between the vehicle  10  and the object  70  is first determined, as explained in reference to  FIGS. 2 a  and 2 b   . A third point in time t 3 ′ is likewise subsequently determined, which is the same, however, as the second point in time t 2  according to this example. An alternative stopping point  86  is also determined according to this embodiment, which lies within a tolerance range surrounding the specified stopping point  83 . In particular, the alternative stopping point  86  lies along the projected trajectory  84  of the vehicle  10  before the specified stopping point  83 . The vehicle  10  can therefore stop at the alternative stopping point  86  x_Fz( 3 ′) at the third point in time t 3 ′, without noticeably slowing down, while the object  70  has already passed by the vehicle  10  at this point in time, and is located at a position x_Ob 1 ( 3 ′) that corresponds to the position x_Ob 1 ( 2 ), and wherein the object  70  exhibits a speed vector v_Ob 1 ( 3 ′) that leads away from the vehicle  10 . There is therefore minimal to no risk of a collision between the object  70  and the vehicle door  15 , or the passenger exiting the vehicle  10 . 
       FIGS. 4 a  and 4 b    show schematic illustrations of the self-driving motor vehicle  10  according to the present disclosure, and the other moving object  70 , at the third point in time t 3″  and at a fourth point in time t 4 , according to an alternative embodiment of the method according to the present disclosure. An existing collision probability between the vehicle  10  and the object  70  is first determined, as explained in reference to  FIGS. 2 a  and 2 b   , and a third point in time t 3″  is determined, at which the vehicle stops at the specified stopping point  83 , which is not shown in  FIG. 4  for purposes of clarity. In differing from  FIG. 2 , there is another passenger at the specified stopping point who wants to board the vehicle  10 . These types of transfers of car sharing vehicles are known to the person skilled in the art. Furthermore, another moving object  71  is detected at the location x_Ob 2 ( 3 ″) in the environment of the vehicle  10  at the point in time t 3″  and moving at a speed v_Ob 2 ( 3 ″). In addition, a projected trajectory of this other object  71  is determined at the point in time  t3″ . Based on the projected trajectory  86  of the second object  71 , it is determined that there is the risk of a collision between the boarding passenger and the second object  71 . Based on this risk of collision, a fourth point in time t 4  is also determined, before which the probability of a collision between the passenger and the second object  71  is extremely low. This fourth point in time t 4  is therefore determined to be the point in time at which the opened vehicle door  15  should be closed. 
     Furthermore, a notification is sent to the passenger outside the vehicle  10  by a second output means  67 , in particular a screen or projector on the exterior of the vehicle, which notifies the passenger of the fourth point in time t 4 , the necessity of boarding before the fourth point in time t 4 , and of the second object  71 . The passenger is therefore warned of the approaching object  71  and boards the vehicle  10  before the fourth point in time t 4 , such that the vehicle door is already closed at the fourth point in time t 4  shown in  FIG. 4 b   , before the second object  71  is within a few meters of the vehicle. The boarding procedure is therefore safely concluded, and the second object poses no danger to the passengers. 
     LIST OF REFERENCE SYMBOLS 
       10  motor vehicle 
       11  first sensor 
       12  second sensor 
       13  third sensor 
       15  vehicle door 
       20  comm. module 
       21  memory 
       22  transponder 
       30  driving system 
       31  memory 
       32  navigation module 
       40  control unit 
       41  memory 
       42  CPU 
       51  fourth sensor 
       52  fifth sensor 
       53  sixth sensor