Vehicle, vehicle system and method for increasing safety and/or comfort during autonomous driving

Abstract

A vehicle, vehicle system and method for increasing at least one of safety and comfort during autonomous driving is provided. The vehicle system includes an autonomous drive arrangement with multiple sensors, a vehicle control arrangement and a positioning system. The vehicle system is configured to determine an estimated probability that at least one sensor will become unavailable, or an estimated time/distance ahead until at least one sensor is determined to become unavailable. The vehicle system is further configured to activate at least one countermeasure based on at least one of the estimated probability, the estimated time and the estimated distance.

Claims

1. A vehicle system configured to increase at least one of safety and comfort during autonomous driving of a host vehicle, the vehicle system comprising: an autonomous drive arrangement comprising a plurality of sensors configured to monitor at least one of a vehicle surrounding and a vehicle communication system status, a processing unit connected to at least one memory unit configured to store sensor data, and a control arrangement configured to control steering and velocity of the host vehicle based on information received from the sensors; and a positioning system configured to determine a host vehicle position and driving direction; wherein the vehicle system is configured to determine, by the processing unit, at least one of an estimated probability that at least one sensor will become unavailable, and an estimated time or distance ahead until at least one sensor is determined to become unavailable, the determination being based on at least one of a detected host vehicle condition or a detected host vehicle surrounding condition, detected by at least one of the plurality of sensors, and host vehicle surrounding condition information stored in the memory unit; wherein the vehicle system further is configured to activate, by the autonomous drive arrangement, at least one first countermeasure based on at least one of the estimated probability, the estimated time and the estimated distance.

2. The vehicle system according to claim 1 wherein the vehicle system is configured to activate, by the autonomous drive arrangement, at least one first countermeasure if the estimated probability that at least one sensor will become unavailable exceeds a threshold probability or if the estimated time or distance ahead until at least one sensor is determined to become unavailable is below a threshold level.

3. The vehicle system according to claim 1 wherein the plurality of sensors is configured to provide detected information on the host vehicle surrounding to the memory unit, such that detected vehicle surrounding information on routes driven by the host vehicle is accessible during subsequent driving on the same routes.

4. The vehicle system according to claim 1 wherein the activation of at least one countermeasure is based on a detected host vehicle surrounding condition, detected by at least one of the plurality of sensor, in a form of sun-light negatively affecting a vehicle camera sensor.

5. The vehicle system according to claim 1 wherein the activation of at least one countermeasure is based on host vehicle surrounding condition information stored in the memory unit, the information being related to a sun position.

6. The vehicle system according to claim 5 wherein the activation of at least one countermeasure is based on stored information related to a sun position combined with information on the host vehicle driving direction received from the positioning system.

7. The vehicle system according to claim 1 wherein the activation of at least one countermeasure is based on a detected host vehicle surrounding condition, detected by at least one of the plurality of sensors, in a form of a weather condition negatively affecting at least one of a camera sensor, a radar sensor and a lidar sensor.

8. The vehicle system according to claim 1 further comprising a communication system configured for communication between the host vehicle and external communication arrangements, wherein the host vehicle is configured to receive data relating to host vehicle surrounding conditions from the external communication arrangements.

9. The vehicle system according to claim 1 further comprising a navigation system configured to provide the autonomous drive arrangement with information on available routes in a road network surrounding the host vehicle and to allow a vehicle operator to input a preferred route.

10. The vehicle system according to claim 8 wherein the activation of at least one countermeasure is based on a detected decreased communication capacity, detected by at least one of the plurality of sensors, between the host vehicle and at least one external communication arrangement.

11. The vehicle system according to claim 8 wherein the activation of at least one countermeasure is based on a host vehicle surrounding condition information indicative of a communication capacity in a predefined geographical area.

12. The vehicle system according to claim 1 wherein a sensor is determined to be unavailable if a sensor performance level is below a threshold sensor performance level, and wherein at least one first countermeasure is activated only if the sensor is determined to be unavailable for a duration of time that exceeds a threshold duration of time.

13. The vehicle system according to claim 1 wherein the vehicle system is configured to activate the at least first countermeasure, the countermeasure selected from a host vehicle operator alert indicative of an upcoming reduced autonomous driving capacity, a disablement of one or more autonomous drive functions, a generation of an alternatively route to a previously selected preferred route, an increase of safety distance to at least one object in the vehicle surrounding, a change of vehicle velocity, a stop of the host vehicle, and activation of dead reckoning.

14. A vehicle comprising a vehicle system according to any one of claim 1.

15. A method for increasing at least one of safety and comfort during autonomous driving of a host vehicle including a vehicle system, the vehicle system comprising an autonomous drive arrangement comprising a plurality of sensors configured to monitor at least one of a vehicle surrounding and a vehicle communication system status, a processing unit connected to at least one memory unit configured to store sensor data, and a control arrangement configured to control steering and velocity of the host vehicle based on information received from the sensors, the vehicle system further comprising a positioning system configured to determine a host vehicle position and driving direction, the method comprising: determining, by the processing unit, at least one of the estimated probability that at least one sensor will become unavailable and the estimated time or distance ahead until at least one sensor is determined to become unavailable, the determination being based on at least one of a detected host vehicle condition or a detected host vehicle surrounding condition, detected by at least one of the plurality of sensors, and host vehicle surrounding condition information stored in the memory unit; and activating, by the autonomous drive arrangement, at least one first countermeasure based on at least one of the estimated probability, the estimated time and the estimated distance.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Various aspects of embodiments herein, including its particular features and advantages, will be readily understood from the following detailed description and the accompanying drawings, in which:

(2) FIG. 1a illustrates a vehicle having a vehicle system according to some embodiments herein.

(3) FIG. 1b illustrates a vehicle having a vehicle system according to some embodiments herein and surrounding vehicles on a road.

(4) FIG. 2a illustrates a vehicle having a vehicle system according to some further embodiments herein.

(5) FIG. 2b illustrates a vehicle having a vehicle system according to some embodiments herein driving from a point A to a point B on a road.

(6) FIG. 3 illustrates a method according to embodiments herein.

DETAILED DESCRIPTION

(7) As required, detailed embodiments are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary and embodiments may take various and alternative forms. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.

(8) Embodiments herein will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown. However, this application should not be construed as limited to the embodiments set forth herein. Disclosed features of example embodiments may be combined as readily understood by one of ordinary skill in the art to which this application belongs. Like numbers refer to like elements throughout.

(9) Well-known functions or constructions will not necessarily be described in detail for brevity and/or clarity.

(10) FIG. 1a illustrates a host vehicle 1, arranged for autonomous driving. The host vehicle 1 may be any vehicle, such as a car, a bus or a truck, which is capable of driving autonomously on a road.

(11) The host vehicle 1 comprises a vehicle system 2, which is arranged to increase safety and/or comfort during autonomous driving of the host vehicle 1. The vehicle system 2 comprises an autonomous drive arrangement 3 and a positioning system 4.

(12) The autonomous drive arrangement 3 comprises a plurality of sensors 5, arranged to monitor a vehicle surrounding. The sensors 5 may be one or more camera sensors 5a, one or more radar sensors 5b and/or one or more lidar-sensors 5c. As illustrated in FIG. 1a, sensors 5 may be arranged at any position in/on the host vehicle 1 from where detection of an interior or exterior condition is possible. Sensors 5 may for example be arranged at a vehicle front-, side and/or rear portion, at a vehicle grille, bumpers, rear-view-mirrors and/or a windshield. Some sensors 5 may be arranged in or near a vehicle compartment, chassis, motor, drivetrain and/or wheels. The sensor 5 position may depend on the type of sensor. For example, a camera sensor 5a and/or a lidar sensor 5c may be arranged at the inside of the windshield, while one or more radar sensors 5b may be arranged in the grille and/or bumpers.

(13) A camera sensor 5a may be e.g. a front- or rear facing digital camera equipped with or connected to one or more processors with object recognition logics. Hereby surrounding objects, such as road lanes, other vehicles, traffic signs, pedestrians, animals, different obstacles etc. may be detected and in some cases, identified/classified. Radar sensors 5b may include transmitters that emit signals that bounces back from object around the host vehicle, and receivers that receive the returned signals. The radar sensors 5b may include e.g. ultra wide band radars, narrow band radars and/or multi node radars. Lidar-sensors 5c may measure distances to objects by illuminating the objects with a laser and analyzing the reflected light. Other types of sensors 5 used to monitor the vehicle surrounding may be e.g. ultrasonic sensors and/or infrared sensors.

(14) Some sensors 5 may be arranged to detect a vehicle communication system status. Such sensors may determine signal strength/accessibility for signals between a communication system in the host vehicle 1 and external communication arrangements. If a signal gets weaker, such that the communication decreases or fails, the sensors 5 may provide the autonomous drive arrangement 3 with information hereof. A communication system status may decrease e.g. due to package loss and/or an decreased signal strength. The signals may relate e.g. to mobile or mobile-data signals (such as GSM 3G, 4G, LTE, 5G) or any satellite and/or global positioning system signals (such as GPS, Galileo, GLONASS).

(15) As illustrated in FIG. 1a, the autonomous drive arrangement 3 comprises at least one processing unit 6 connected to at least one memory unit 7, arranged to store sensor data. In some embodiments the one or more processing units 6 are used for processing in several different vehicle systems. Some processing units 6 may be dedicated to a specific processing task. In some embodiments the host vehicle 1 and/or the vehicle system 2 may comprise a large number of processing units 6. The one or more processing units 6 may be central processing units, CPUs, also referred to as central processor units, that carries out instructions of computer programs/software, which, when executed perform basic arithmetical, logical, and input/output operations. The vehicle system 2 may also comprise an accelerated processing unit, APU, also referred to as an advanced processing unit. An APU is a processing unit that includes additional processing capability designed to accelerate one or more types of computations outside of the CPU. One or more processing units 6 may comprise application programming interfaces, APIs, which specify how software components may interact with each other.

(16) The one or more processing units 6 comprise and/or are connected to one or more memory units 7. The one or more memory units 7 may be arranged in the host vehicle 1 and/or outside of the host vehicle 1. In some embodiments, the one or more processing units 6 may save information to the so called cloud, e.g. memory units 6 arranged in remote servers.

(17) The autonomous drive arrangement 3 further comprises an electrical/mechanical control arrangement 8, arranged to control steering and velocity of the host vehicle 1 based on information received from the sensors 5. The control arrangement 8 is connected to a vehicle steering system, such that the control arrangement 8, directly or indirectly, may control a direction of at least some of the wheels of the host vehicle 1. Hereby e.g. a yaw rate of the host vehicle 1 may be adjusted, such that the driving direction of the host vehicle 1 is adjusted in accordance with the input from the control arrangement 8. The control arrangement 8 is also connected to a vehicle engine and a vehicle braking system, such that the control arrangement 8, directly or indirectly, may control acceleration and/or deceleration of the host vehicle 1. The control arrangement 8 may e.g. increase a vehicle velocity by increasing the engine speed, and decrease the vehicle velocity by motor-braking or by activation of one or more wheel brakes. The control arrangement 8 may e.g. be connected to an ABS (anti-lock braking system), such that one or more wheel brakes may be activated selectively.

(18) As illustrated in FIG. 1a, the vehicle system 2 comprises a positioning system 4, arranged to determine a host vehicle position and driving direction/heading. The positioning system 4 may determine the host vehicle position and driving direction e.g. via a satellite based global positioning system and/or matching relatively a map. A compass may be used for determination of a vehicle direction. The positioning system 4 may comprise or be connected to a navigation system.

(19) The processing unit 6 is arranged to determine an estimated probability that at least one sensor 5 will become unavailable and/or an estimated time to or distance ahead until at least one sensor 5 is determined to become unavailable. The probability that at least one of the sensors 5 will become unavailable within a certain time amount or within a certain distance ahead of the host vehicle 1 is based on a host vehicle 1 or host vehicle surrounding condition, detected by one or more sensors 5, and/or host vehicle surrounding condition information, previously detected and stored in the memory unit 7. The vehicle system 2 is further arranged to activate, by the autonomous drive arrangement, at least one first countermeasure, based on the estimated probability and/or the estimated time and/or the estimated distance.

(20) According to some embodiments a sensor is determined to be unavailable if a sensor performance level is below a threshold sensor performance level, and in that at least one first countermeasure is activated only if the sensor is determined to be unavailable for a duration of time that exceeds a threshold duration of time. The duration of time may depend e.g. on host vehicle surrounding conditions, host vehicle velocity, traffic intensity. According to some embodiments, the threshold duration of time may be one or a few seconds, such as 1-15 s. According to some embodiments, the threshold duration of time may be about 3 s.

(21) FIG. 1b illustrates the host vehicle 1 and the vehicle system 2 as seen from above. During autonomous driving, the sensors arranged in/on the host vehicle 1 are arranged to continuously monitor the host vehicle surrounding along a road 10, on which the host vehicle 1 is travelling. The sensors thus gather the type of information that a vehicle operator normally perceives through his/her senses during manual or semi-manual driving. The information may relate to any factor which may affect a current or upcoming traffic situation. The detected information may e.g. relate to road direction, road surface, road friction, road lanes, surrounding climate and weather conditions, light conditions, other vehicles, objects, pedestrian, bicyclists, animals etc. on or in the vicinity of the road, nearby buildings or obstacles, traffic intensity, general traffic information, upcoming crossings etc.

(22) The information detected via the sensors is used as input to the host vehicle control arrangement. The control arrangement may be configured to control the steering and velocity of the host vehicle 1 in a manner that an attentive and experienced driver would have done in a similar situation, i.e. to follow a traffic rhythm and avoid potentially dangerous situations. For example, if sensors detect that a distance 15a to a slower driving vehicle 12 ahead of the host vehicle 1 decreases below a predefined safety distance, or with a closing velocity above a threshold velocity, the vehicle system 2 may be configured to apply the brakes of the host vehicle 1. If a distance 15b, 15c to surrounding vehicles 12 becomes too small, the host vehicle 1 may adjust its lateral position, such that the distance 15b, 15c is increased. The vehicle system 2 may be configured to increase the safety margins to other vehicles more in higher speeds, and may adjust brake forces and yaw rates e.g. in accordance with detected ice or other slippery surfaces on the road 10.

(23) The vehicle system 2 is dependent on robust sensor information in order to provide autonomous driving functionality. If one or more sensors becomes defect, blocked or in any other way unavailable to detect the host vehicle surroundings and/or a vehicle communication system status, the host vehicle operator may have to take control over the vehicle until the sensor or sensors functions properly again. In order to avoid that the vehicle operator will have to take control of the host vehicle 1, if one or more sensors become unavailable, the processing unit is arranged to determine the estimated probability that at least one sensor will become unavailable and/or the estimated time or distance ahead until at least one sensor is determined to become unavailable. The probability that at least one of the sensors will become unavailable, within a certain amount of time or within a certain distance ahead of the host vehicle 1, is based on a detected host vehicle or host vehicle surrounding condition, detected by one or more sensors, and/or host vehicle surrounding condition information stored in the memory unit. The vehicle system 2 is further arranged to activate at least one first countermeasure, based on the estimated probability and/or the estimated time and/or the estimated distance.

(24) In FIG. 2a the host vehicle 1 is illustrated in a road environment. The host vehicle 1 is depicted when driving on a road 10 provided with road markings 11. Ahead of the host vehicle 10 a surrounding vehicle 12 is illustrated.

(25) The host vehicle 1 comprises the vehicle system 2, which allows the host vehicle 1 to drive autonomously. The host vehicle 1 may therefore be referred to as an autonomous vehicle, in which many or all of vehicle operator tasks, such as steering, accelerating and braking are performed automatically by the vehicle system 2. The vehicle operator may instead focus on secondary tasks, such as reading, socializing or browsing the internet, instead of the otherwise primary task of driving the vehicle. The vehicle system 2 may comprise and/or be connected to a number of co-operating subsystems, such as adaptive cruise control systems, lane departure control systems, collision avoidance system, traffic sign recognition systems, communication systems, navigation systems, ultrasonic sensor systems, infrared camera systems, inertial measuring systems, intelligent transportation systems, safe road train systems, automatic parking systems etc.

(26) According to some embodiments, the activation of at least one countermeasure is based on a, by at least one of the sensors 5, detected host vehicle surrounding condition in form of sun-light, negatively affecting a vehicle camera sensor 5a. This scenario is depicted in FIG. 2a. When the host vehicle 1 autonomously drives in a direction where a longitudinal direction of the host vehicle 1, or a monitoring field direction 5d of the camera sensor 5a, is larger than a predetermined angle relative to the sun 13, the camera sensor 5a is determined to be available. When the host vehicle 1 continues along the road 10 in FIG. 2a, the angle relative to the sun 13 will decrease. When the longitudinal direction of the host vehicle 1 or the monitoring field direction 5d of the camera sensor 5a is equal or less than the predetermined angle to the sun 13, the risk that the sun 13 shines straight into the lens of the camera sensor 5a is high. The lens may become saturated, whereby the sensor 5a may fail to provide sensor information on the host vehicle surrounding to the control arrangement 8. If the sensor 5a fails to provide sensor information on the host vehicle surrounding to the control arrangement 8, the sensor 5 is determined to be unavailable. The vehicle system 2 may use information on an upcoming road direction, a selected route and/or historical data for the determination of the time and/or distance until the sensor is determined to become unavailable.

(27) Since expected upcoming sensor unavailability is determined before the sensor 5 actually becomes unavailable, one or more countermeasures to the determined sensor unavailability may be activated. In the FIG. 2a-illustration, where the host vehicle driving direction approaches the sun 13, such a determination may be based on factors such as the luminous intensity of the sun 13 and the vertical and/or horizontal distance between the host vehicle driving direction and the position of the sun. The relationship may be expressed e.g. as a mathematical formula. Upcoming curves and crests, clouds, houses, trees, particles in the atmosphere etc. may be taken into account for the determination. The determination may also be based on the present time of the day, the geographical position of the host vehicle etc. For example, a sensor may be determined to be unavailable if a probability that the sensor will stop to function properly is higher than a pre-defined probability, According to some embodiments such probability may be between 50-99%, such as 60%, 70%, 80% or 90%.

(28) The vehicle system 2 may be arranged to activate, by the autonomous drive arrangement 3, at least one first countermeasure if the estimated probability that at least one sensor will become unavailable exceeds a threshold probability or if the estimated time or distance ahead, until at least one sensor is determined to become unavailable, is below a threshold level. Different threshold levels may be selected, e.g. depending on which level of safety that is required, and if information from available sensors may compensate for the determined sensor unavailability.

(29) According to some embodiments, the plurality of sensors 5 may be arranged to provide detected information on the host vehicle surrounding to the memory unit 7, such that detected vehicle surrounding information on routes driven by the host vehicle 1 is accessible during subsequent drive along the same routes.

(30) As mentioned above, several types of sensors 5 may be used to monitor the host vehicle surroundings. According to some embodiments, the activation of at least one countermeasure may be based on a, by at least one of the sensors, detected host vehicle surrounding condition in form of a weather condition, negatively affecting at least one of a camera sensor, a radar sensor and a lidar sensor.

(31) In some situations, a sensor 5 may be unavailable due to obstacles near the road 10. In FIG. 2a the vehicle system 2 may determine that e.g. a camera sensor 5a will be at least temporarily unavailable if e.g. a building 14 blocks a part of or the entire monitoring field 5d. A sensor 5 may also be determined to be unavailable due to a curve or a crest. A radar sensor 5b may not be able to detect relevant areas of the host vehicle surrounding if its field of view is blocked by obstacles. Radar sensors 5b may also be blocked e.g. due to rain, snow and water spray from surrounding vehicles. During certain temperature and/or humidity conditions, moisture on the inside of the windshield may be predicted in advance, e.g. from communicated weather forecasts. A sensor may be determined to be unavailable during such conditions.

(32) In FIG. 2b the host vehicle 1 is illustrated on a road in a road network 10a, 10b. In this illustrated embodiment the host vehicle 1 is about to autonomously drive from point A to point B. According to some embodiments the vehicle system 2 comprises a communication system arranged for communication between the host vehicle 1 and external communication arrangements. The host vehicle 1 may then be arranged to receive data relating to host vehicle surrounding conditions from the external communication arrangements. According to some embodiments, the vehicle system 2 further comprises a navigation system arranged to provide the autonomous drive arrangement with information on the available routes 10a, 10b of the road network surrounding the host vehicle 1 and to allow a vehicle operator to input a preferred route. The navigation system may be connected to the abovementioned positioning system 4.

(33) Due to the detected and/or received information, or due to information detected and saved during previously driven routes along the routes 10a, 10b, the vehicle system 2 may be aware of the expected conditions prevailing along the routes. If a camera sensor during previously driven routes became unavailable due to a particular sun position at a particular time of the day, this information may be used to activate a countermeasure to the unavailability during later trips along the same route.

(34) A few examples are given with reference to FIG. 2b. A vehicle operator may like to autonomously travel from point A to point B. If the vehicle system 2 determines that sensor unavailability is likely to occur during route 10b, which may make autonomous driving impossible, it may select, or recommend the driver to instead select route 10a.

(35) Obstacles, sharp curves and/or crests, weather forecasts, information on road construction sites, accident sites etc. may be communicated as map data to the host vehicle 1. Some information may be detected by the host vehicle sensors 5 before they are determined to be unavailable.

(36) Examples of surrounding conditions which may negatively affect a sensor 5 are given in the following. Diffuse lane markers 16 may negatively affect a camera sensor. A tunnel 17 may negatively affect a GPS-signal-sensor. The sun 13 may negatively affect a camera sensor. In a predefined or delimited geographical area 18 a communication capacity may be insufficient, which may negatively affect a signal between the host vehicle 1 and external communication arrangements, such as servers, roadside units, surrounding vehicles and/or intelligent traffic systems.

(37) Thus, according to some embodiments, the activation of at least one countermeasure is based on host vehicle surrounding condition information, indicative of a communication capacity in the predefined geographical area 18. Hence, a countermeasure may be activated e.g. if a data signal or positioning signal becomes weaker. This may be the case e.g. if the host vehicle 1 is far from a telecommunication-mast, or if a signal is blocked e.g. by the illustrated mountain 19.

(38) As mentioned above, one or more countermeasures may be activated when a sensor is determined to become unavailable. For example, two, three, four or five different countermeasures may be activated. The one or more countermeasures may include: activation of a host vehicle operator alert, indicative of an upcoming reduced autonomous driving capacity, disablement of one or more autonomous drive functions, generation of an alternative route to a previously selected preferred route. In FIG. 2b, the vehicle system may generate the route 10a instead of route 10b if it is determined that route 10b may render autonomous driving impossible.

(39) A countermeasure may also be: an increase safety distance between the host vehicle 1 and at least one object in the host vehicle surrounding, a change of vehicle velocity, stopping the vehicle or a lateral displacement. A countermeasure may also be dead reckoning. Dead reckoning is a process for estimating a value (e.g. indicative of a velocity and/or a position) based on earlier values, together with occurring changes. If a sensor becomes unavailable, dead reckoning may be used to continue to control the vehicle along a path determined when sensors were available. Hence, historically gathered data may be used for shorter periods of time until sensor information is available again.

(40) FIG. 3 illustrates a method 100 for increasing at least one of safety and comfort during autonomous driving of a host vehicle, where the host vehicle comprises a vehicle system with: an autonomous drive arrangement, the autonomous drive arrangement comprising a plurality of sensors arranged to monitor at least one of a vehicle surrounding and a vehicle communication system status, a processing unit connected to at least one memory unit, arranged to store sensor data, a control arrangement, arranged to control steering and velocity of the host vehicle based on information received from the sensors.

(41) The autonomous drive arrangement also comprises a positioning system, arranged to determine a host vehicle position and driving direction.

(42) The method 100 comprises the steps of determining 101, by the processing unit, at least one of the estimated probability that at least one sensor will become unavailable and the estimated time or distance ahead until at least one sensor is determined to become unavailable. The determination is based on at least one of a, by at least one of the sensors, detected host vehicle or host vehicle surrounding condition and a host vehicle surrounding condition information stored in the memory unit, and activating 102, by the autonomous drive arrangement, at least one first countermeasure based on at least one of the estimated probability, the estimated time and the estimated distance.

(43) If the determination of sensor unavailability is based on a, by at least one of the sensors, detected host vehicle surrounding condition, the time/distance may be small. For example, if water splash from a surrounding vehicle is detected, the time until the sensor is determined to be unavailable may be e.g. a few milliseconds or a few seconds. If a sunset ahead is detected, the time until the sensor is determined to be unavailable may be e.g. a few seconds or a few minutes. If the host vehicle surrounding condition is stored in the memory unit, the time until the sensor is determined to be unavailable may be longer, such as minutes or hours ahead.

(44) Although aspects have been described with reference to example embodiments, many different alterations, modifications and the like will become apparent for those skilled in the art. Therefore, it is to be understood that the foregoing is illustrative of various example embodiments and the scope of the appended claims is not to be limited to the specific embodiments disclosed and that modifications to the disclosed embodiments, combinations of features of disclosed embodiments as well as other embodiments are intended to be included within the scope of the appended claims.

(45) As used herein, the term “comprising” or “comprises” is open-ended, and includes one or more stated features, elements, steps, components or functions but does not preclude the presence or addition of one or more other features, elements, steps, components, functions or groups thereof.

(46) While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the disclosure. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. Additionally, the features of various implementing embodiments may be combined to form further embodiments.