ESTIMATE DRIVER DISTRACTION DEGREE

Description

[0001] The invention relates to a device for estimating the degree of distraction of a driver while driving a motor vehicle, as well as a corresponding system, method and computer program.

[0002] Modern vehicles, in addition to primary controls such as the steering wheel and pedals, offer driver controls that can distract the driver from the road. These include, for example, the vehicle's infotainment system and additional displays in the instrument cluster, such as driving data, radio information, driver assistance system (DAS) displays, instrument cluster settings, and so on. Operating and viewing these elements distracts the driver and prevents them from fully concentrating on driving, resulting in an increased risk to the driver, passengers, and / or other road users.

[0003] Publication US 2020 O 198 645 A1 concerns a driver distraction detection system. The detection system comprises an integrated data acquisition and computing system that includes inertial sensors, internal sensors, and external sensors. During a journey, the data acquisition system samples data from the sensors to determine steering activity metrics and driver behavior. A steering activity metric is a representation of the driver's steering inputs while driving. Driver behavior is a representation of how distracted the driver is while driving. By performing the above steps, the system can provide an analysis of the driver's distraction and optionally take control of the vehicle to prevent aberrant behavior. A disadvantage is that an exact determination of the driver's distraction is not possible, as only attention-reducing data is considered.

[0004] Document US 10,246,014 B2 relates to a method for determining the distraction of a vehicle driver, including sensor measurements using an onboard system of the vehicle; generating an output indicating a distracted state; determining, based on the output, that the vehicle driver is characterized by the distracted state; generating a second output using a second distraction detection module of a remote computer system, indicating that the driver is characterized by the distracted state, based on the sensor measurements; and calculating a distraction score at an evaluation module of the remote computer system in response to the generation of the second output and based on the sensor measurements and the distracted state. A disadvantage of this method is that it requires a complex analysis to determine driver distraction, which is performed on a remote computer system.Consequently, a stable data connection between the remote computer system and the vehicle is required. The method can therefore only be reliably executed if a data connection exists. The disclosed teaching is thus error-prone, complex, and costly.

[0005] Document US 10,752,261 B2 relates to a control device and a control procedure for a driver distraction warning. The control device comprises a sensor device that detects a driver's gaze, an adjustment device configured to divide a virtual area in front of the driver into multiple viewing zones and to set a threshold for each viewing zone, a determination device that selects a viewing zone corresponding to the driver's gaze direction from the viewing zones, and a control device that controls the driver distraction warning based on the threshold set for the selected viewing zone. The only disadvantage is that a block of driver guidance is used to determine the driver's distraction.An accurate and reliable determination of the driver's distraction is not possible, as only small amounts of data are taken into account.

[0006] Document US 6,756,903 B2 relates to a system and method for determining the alertness of a driver of a motor vehicle, including acquiring at least one first motion characteristic of at least one first part of a motor vehicle, acquiring at least one second motion characteristic of at least one second part of the motor vehicle, using at least one temporal relationship between the at least one first motion characteristic and the at least one second motion characteristic to detect and distinguish driver-initiated movements from non-driver-initiated movements, and to determine the alertness of the driver of the motor vehicle based on at least one relationship between the driver-initiated movements and the non-driver-initiated movements.A precise and reliable determination of driver distraction is not possible because only limited data regarding vehicle behavior is considered. Driver actions that have no effect on vehicle behavior can indicate driver distraction. The described method is therefore imprecise.

[0007] Document US 6,813,562 B2 relates to an algorithm for use in a predictive collision warning system for use in a vehicle. The collision warning system includes a radar unit that generates path files containing the distance and speed of objects in the vehicle's path. The system further includes a collision warning processor that executes the algorithm, which receives the path files and various input data to determine whether and to what extent a warning of a potential collision should be issued. The input data includes the vehicle's speed and acceleration, whether the vehicle's brakes are applied, the sensitivity to collision warnings, driver distraction modifiers, road condition data such as wiper speed and ambient air temperature, and so on.The processor calculates an alarm level based on various inputs and outputs this level to a driver-vehicle interface to inform the driver of a potential collision. A disadvantage of this system is that it only warns the driver of an impending collision. Preventive warnings for excessive driver distraction are not described. The system cannot mitigate or prevent other consequences of excessive driver distraction, such as leaving the roadway.

[0008] German patent application DE 601 15 693 T2 describes a method for informing a vehicle operator to improve their performance. This involves monitoring an interior section of the vehicle and estimating operator activity data. The method also estimates the operator's cognitive load by synthesizing and summarizing vehicle operating data, operator activity data, and operator state data. In this way, the driver's physical condition and level of distraction are monitored. An alarm or warning can be issued if necessary.

[0009] Document US 2020 / 122734 A1 describes an emergency control device for a vehicle. The emergency control device comprises a sensor configured to measure an area inside or outside the vehicle, a processor configured to process the data collected by the sensor, and a controller configured to control the vehicle by reflecting the data processed by the processor, wherein the sensor detects whether a driver is inattentive, the processor determines the degree of the driver's inattentiveness according to the detected state of the driver, and the controller controls the vehicle according to the degree of the driver's inattentiveness.

[0010] German patent application DE 10 2018 216 511 A1 describes a method for estimating the driver's attention in a vehicle. This method uses a long-term estimate to determine an initial attention value, which decreases as the vehicle's driving time increases. The method then detects any interaction the driver has with vehicle controls. Based on this detected interaction, a second attention value is determined using a short-term estimate of the driver's attention. Depending on the first and / or second attention value, a message can be issued to the driver or a vehicle function can be triggered.

[0011] The invention is based on the objective of creating an improved way to determine a driver's level of distraction and preferably to warn the driver in a convenient manner.

[0012] This task is solved by a device for estimating the degree of distraction of a driver while driving a motor vehicle, with: an input interface for receiving driver data, including operating data and sensor data with information on driver behavior during driving; an analysis unit for determining a variable level of driver distraction based on the driver data; an output interface for transmitting a control command to an output unit, which causes a warning to be issued to the driver when the analysis unit detects a level of distraction greater than a predefined threshold, in order to alert the driver to an increased level of distraction, wherein the level of distraction is represented by an index indicating the driver's current state of attention and having a neutral level of attention as a reference value, wherein the index can take values ​​indicating both a higher level of attention than the neutral level of attention and values ​​indicating a lower level of attention than the neutral level of attention.wherein the analysis unit is trained to detect an increase in the level of distraction based on a predefined behavior of the driver during the journey, and a decrease based on a predefined behavior of the driver during the journey, and to adjust the index accordingly, and wherein the analysis unit is trained to continuously reduce the index according to a gradient to the neutral level of attention if no predefined behavior of the driver indicating an increase or decrease in the level of distraction is detected over a parameterizable time.

[0013] The above problem is further solved by a system for estimating the degree of distraction of a driver while driving a motor vehicle, with: a device as previously described; and an output unit for issuing a warning to the driver when the analysis unit detects a level of distraction that is greater than a predefined threshold, in order to alert the driver to an increased level of distraction.

[0014] Finally, the above problem is solved by a method for estimating the degree of distraction of a driver while driving a motor vehicle, preferably by means of a device and / or system as previously described, comprising the steps: Receiving driver data, including operating data and sensor data with information on driver behavior during driving; determining a driver distraction level based on the driver data; transmitting a control command to an output unit that issues a warning to the driver when a determined distraction level is greater than a predefined threshold to alert the driver to an increased level of distraction, wherein the distraction level is represented by an index indicating the driver's current state of attention and having a neutral level of attention as a reference value, where the index can take values ​​indicating both a higher level of attention and a lower level of attention than the neutral level of attention;wherein, based on a predefined driver behavior during the journey, an increase in the level of distraction is determined, and based on a predefined driver behavior during the journey, a decrease in the level of distraction is determined, and the index is adjusted accordingly, and the index is continuously reduced according to a gradient to the neutral level of attention if no predefined driver behavior indicating an increase or decrease in the level of distraction is detected over a parameterizable time.

[0015] An input interface enables the creation of a cost-effective device that can preferably be used with existing sensors and units installed in the vehicle. This input interface can be wired and / or wireless and preferably supports one or more communication protocols. An analysis unit can reliably detect driver distraction. By determining an increase and / or decrease in the degree of distraction based on predefined driver behavior during driving, unnecessary driver warnings can be prevented. A more precise determination of driver distraction is possible. This reduces the number of warnings issued, ensuring the driver takes them seriously. Driver desensitization due to excessive warnings can be counteracted. Road safety is increased.An output interface enables a cost-effective device that can preferably be used with existing output devices.

[0016] In a preferred embodiment of the invention, the operating data includes information regarding the activation of a control device in the area of ​​a driver's workstation, in particular a control unit of a central display and / or a center console, a control unit of a multifunction steering wheel, a control unit for adjusting mirrors, a control unit for adjusting seats, a control unit of an electric window regulator, a control unit for adjusting the interior light, and / or a control unit for adjusting the sunroof. By detecting the activation of a control device, it can be technically easily determined that the driver is not engaged with a device for primary vehicle control and, consequently, that the driver is receiving less attention to vehicle control, at least temporarily. This detection can be performed by a sensor.Furthermore, a control command generated by the operating device can be received via the device's input interface. For example, a control unit for adjusting mirrors transmits a signal or control command to a mirror adjustment unit. This control command can be received by the input interface.

[0017] In a further preferred embodiment of the invention, the operating data includes information regarding the operation of primary vehicle control devices, in particular pedals and / or steering wheel position; and / or the sensor data includes information on the vehicle's driving behavior, in particular its acceleration behavior, and / or information regarding the driver, in particular driver observation by a camera. Based on the information regarding primary vehicle control devices, the quality of vehicle handling can be reliably determined. For example, a sharp change in the steering angle or strong acceleration or deceleration of the vehicle can indicate active, intentional control of the vehicle by the driver and suggest a high level of attention or low distraction on the part of the driver.In particular, acceleration behavior includes positive acceleration and negative acceleration, i.e., deceleration behavior.

[0018] In a further preferred embodiment of the invention, the analysis unit is configured to determine a warning time based on a data fusion of the operating data and sensor data, wherein the control command causes the warning to be issued to the driver at the warning time. Data fusion allows for improved determination of the warning time. In particular, false warning messages can be avoided. Furthermore, this makes it technically easy to take into account both attention-enhancing and attention-decreasing actions of the driver.

[0019] In a further preferred embodiment of the invention, the analysis unit is configured to assign a, preferably weighted, expected driver distraction to a driver input and / or driver action. In particular, the analysis unit is configured to assign a parameterizable attention potential to each driver distraction in order to determine the effect of the driver distraction on the driver's level of distraction. This improves the accuracy and sensitivity of the device. The driver's attention can be modeled by assigning a parameterizable attention potential. By weighting the expected driver distraction, a driver-specific, individual assessment of the driver distraction can be performed.

[0020] In a further preferred embodiment of the invention, the analysis unit is configured to assign a duration to driver distraction that corresponds to the duration of the driver's distraction caused by and / or resulting from the operating input and / or driver action. This allows for a further improvement in the estimation of driver distraction. In particular, it ensures that driver distraction caused by an operating input and / or driver action is taken into account for the entire duration of the distraction and not just for the moment of operation. Furthermore, after the distraction period, the estimated driver distraction can return to a normal value.For example, the time a driver spends focusing their attention on an infotainment system to read and understand the displayed information such as outside temperature, range, etc., can be taken into account, after which normal driver distraction / attention can be assumed again.

[0021] In a further preferred embodiment of the invention, the analysis unit is configured to assign the expected driver distraction of a single input and / or action to a plurality of identical operating inputs and / or driving actions within a predefined dead time. This allows the estimation of driver distraction to be further refined. It has been shown that a driver is not more distracted by several, especially similar, consecutive operating inputs and / or driving actions, but rather is distracted for a longer period.

[0022] Further preferred embodiments of the invention result from the other features mentioned in the dependent claims.

[0023] A driver attention can preferably be estimated using the following method: Upon a driver input, the method detects an event, which is then weighted according to the expected driver distraction. Each event can be parameterized and assigned an attention potential, for example, ranging from highly attention-grabbing to neutral to highly distracting. Additionally, a duration or dwell time is determined, corresponding to the expected duration of the driver's distraction for the specific event. If the driver makes several identical inputs in quick succession, these are filtered out within a defined time interval or dead time, as it is assumed that the driver is distracted for a longer period, not more intensely. An index is then calculated from the events.The index can rise, indicating that the driver is currently becoming increasingly distracted, and it can fall due to specific operating actions, such as strong acceleration / braking or sharp steering, which indicates that the driver is once again attentive to driving. If no further events are detected over a configurable period, the index returns to a neutral value. If the index exceeds a predefined threshold, the system issues a distraction warning.

[0024] The driver's workplace is in particular the driver's seat and the area around the driver's seat with controls that a driver can operate while driving.

[0025] Unless otherwise stated in individual cases, the various embodiments of the invention mentioned in this application can be advantageously combined with one another.

[0026] The invention is explained below using exemplary embodiments with reference to the accompanying drawings. These show: Figure 1 is a schematic simplified representation of a device according to the invention; Figure 2 is a schematic simplified representation of a system according to the invention; Figure 3 is a schematic representation of a situation in a motor vehicle; Figure 4 is a schematic representation of a driver's workplace; Figure 5 shows schematic diagrams for determining the degree of distraction of a driver; and Figure 6 schematically shows the process steps of a method according to the invention.

[0027] Figure 1Figure 10 shows a device according to the invention for estimating the degree of distraction of a driver while driving a motor vehicle, comprising an input interface 12, an analysis unit 14, and an output interface 16. It is understood that the input interface 12 and the output interface 16 can also be configured together as a transceiver. The separate representation chosen here serves for clarity.

[0028] The input interface 12 is designed to receive comprehensive operating data and sensor data from driver data, including information on the driver's behavior during the journey.

[0029] Preferably, the operating data can include information regarding the activation of a control device in the area of ​​a driver's workplace, in particular a control unit of a central display and / or a center console, a control unit of a multifunction steering wheel, a control unit for adjusting mirrors, a control unit for adjusting seats, a control unit of an electric window regulator, a control unit for adjusting the interior light, a control unit for adjusting the sunroof, and information regarding devices for primary vehicle control, in particular pedals and / or steering wheel position. The sensor data can preferably include information on the driving behavior of the vehicle, in particular the acceleration behavior of the vehicle, and / or information regarding the driver, in particular driver observation by a camera.

[0030] Analysis Unit 14 is designed to determine a variable level of driver distraction based on driver data. Analysis Unit 14 can be, for example, a circuit, switching logic, or a unit of the vehicle's on-board electronics. For instance, an increase and / or decrease in the level of distraction can be determined based on predefined driver behavior during driving.

[0031] The output interface 16 is configured to transmit a control command to an output unit, which causes an output of a warning to the driver when the analysis unit 14 detects a level of distraction that is greater than a predefined threshold, in order to warn the driver of an increased level of distraction.

[0032] Figure 2Figure 18 shows a system 18 for estimating the degree of driver distraction during a journey, comprising a device 10 and an output unit 20. The system 18 further includes primary vehicle control devices 22, such as a steering wheel 24. The system 18 may also include a steering angle sensor 26. Furthermore, the system 18 includes a sensor in the form of a camera 28, preferably directed towards the driver of the vehicle to detect the driver's movements and / or facial expressions, etc. It is understood that the camera 28 may also include a microphone to detect sounds inside the vehicle.

[0033] The output unit 20 can, for example, be a display in an instrument cluster, a vibration module in the seat and / or steering wheel 24, a loudspeaker, and / or a warning light. Furthermore, the output unit 20 can include a reversible belt tensioner for a belt jolt and / or a braking device for a brake jolt. It is understood that the device 10 can also be extended by a corresponding output unit 20.

[0034] Using System 18, the driver's level of distraction can be determined as described above, and the driver can be warned if their level of distraction exceeds a predefined threshold. It is understood that an embodiment is conceivable in which the driver can determine or influence the threshold at which a warning is issued. For example, the driver can adjust the sensitivity of System 18 in the infotainment system and thus influence the warning threshold. In particular, it is conceivable that the driver can choose between three sensitivity values ​​and thus adapt System 18 to their needs.Furthermore, it is conceivable that the driver can determine the type of warning himself, i.e., whether it is an audible warning, a visual warning in the form of a display on an instrument cluster or by the illumination of a light, or a haptic warning, for example, by vibration of the steering wheel 24 or a driver's seat. It is also understood that the system 18 can be implemented by a smartphone, whereby the smartphone is connected to the vehicle and is designed to receive driver data and / or at least partially record it using sensors on the smartphone.

[0035] In Figure 3A schematic representation of a situation in a motor vehicle 30 is shown, wherein the motor vehicle 30 includes a system 18 as previously described. In the example shown, a driver can be observed by means of the camera 28 during a journey, whereby driver behavior is evaluated by the system 18 and, if necessary, a warning can be issued by means of the output unit 20 in the form of a display.

[0036] For example, driver inputs can be recorded by camera 28. It is understood that eye movements, in particular the driver's gaze direction, can also be recorded, whereby a gaze directed towards a control element and / or a display suggests a higher degree of driver distraction, and a gaze directed through the windshield suggests increased driver attention.

[0037] In Figure 4Figure 1 schematically shows a driver's workstation in a motor vehicle 30 with a system 18. The driver's workstation includes devices for primary vehicle control 22, such as a steering wheel 24, pedals 32, and a shift unit 34. The driver's workstation also includes operating devices, such as a control unit for adjusting the mirrors 36, a control unit for an electric window regulator 38, a control unit for a central display 40, in particular in the form of a touchscreen display, and a control unit for an instrument cluster 42. Preferably, the instrument cluster 42 is operated by means of a multifunction steering wheel, which may also include further operating elements. Furthermore, the driver's workstation includes, not for the sake of clarity, a more precisely defined control unit for the multifunction steering wheel, a control unit for the climate control system, and a control unit for adjusting the seat.It is understood that the driver's workplace may include further control units and that only an exemplary selection has been shown here to describe the invention.

[0038] The driver's level of attention while driving can be determined by observing the operation of various devices. For example, if a device for primary vehicle control 22 is operated, the system 18 can detect increased driver attention and preferably not issue a warning. The operation of a control device not related to primary vehicle control indicates decreased driver attention. If the driver's attention falls below a predefined threshold, i.e., if the driver's level of distraction exceeds a predefined threshold, a warning can be issued to the driver to increase their attention.

[0039] It is understood that the driver's attention is inversely proportional to the driver's level of distraction. Therefore, within the scope of this application, a high level of attention corresponds to a low level of driver distraction, and vice versa.

[0040] Figure 5 Figure 44, 46, and 48 show schematic diagrams for determining a driver's degree of distraction. In Figures 44, 46, and 48, time is plotted on an x-axis. The time axis is the same for Figures 44, 46, and 48, with the same common time points highlighted by vertical dashed lines for better comparability. Individual data points are indicated by circles 50. It is understood that the procedure described with respect to Figures 44, 46, and 48 can be carried out using a device 10 as described above.

[0041] In the upper diagram 44, 52 operating inputs and / or driver actions are plotted on the Y-axis. Inputs and / or driver actions that increase attention are plotted above the X-axis, while those that decrease attention are plotted below the X-axis. The distance from the X-axis indicates the degree to which the inputs and / or driver actions influence the driver's attention or distraction, i.e., the expected driver distraction. A double arrow represents a dead time 54, where identical inputs and / or driver actions within this dead time 54 have no additional influence on determining the driver's level of distraction. It is understood that different inputs and / or driver actions can be assigned different dead times 54.

[0042] In the middle diagram 46, 56 dwell times 58 are plotted on the Y-axis. The dwell times 58 are preferably always positive. A dwell time 58 is understood to be the period during which an operating input and / or driver action is attributed an effect on the driver's degree of distraction. The decrease in dwell time 58 is clearly indicated by lines running diagonally to the X-axis. It is understood that a corresponding slope of the lines, or duration of the dwell time 58, can be individually assigned to individual operating inputs and / or driver actions. For simplification, a uniform dwell time 58 can also be assumed for each of the operating inputs and / or driver actions.

[0043] In the lower diagram 48, the determined driver distraction level 62 is plotted on the Y-axis 60. This level can be determined, for example, based on a parameterizable attention potential for an operating input and / or driver action. A threshold value 64 for insufficient attention is shown as a horizontal dashed line. A maximum value 65 for driver distraction is shown as a solid line. Preferably, the driver's distraction level cannot exceed the maximum value 65. The threshold value 64 for a message is preferably below the maximum limit, i.e., the maximum value 65. A neutral attention level is shown as a horizontal dashed line and labeled 66. If the driver's distraction level 62 exceeds the threshold value 64, a message 68 is issued to the driver.

[0044] The attention potential is preferably a measure of how strongly an operating input and / or driver action affects the driver's distraction level 62. The expected driver distraction is preferably a measure of how strongly an operating input and / or driver action affects the dwell time 58.

[0045] In diagrams 44, 46, and 48, it can be seen from left to right that the driver's distraction level 62 increases due to several attention-reducing operating inputs and / or driving actions. The first four operating inputs and / or driving actions were performed within the dead time 54. Therefore, the determined distraction level 62 only increased with respect to the first of the four operating inputs and / or driving actions. A fifth operating input and / or driving action occurred outside the dead time 54 and resulted in a further increase in the distraction level 62. After the holding time 58 has elapsed, the distraction level 62 steadily returns to a neutral attention level 66.

[0046] Due to a further, more attention-reducing input and / or driving action, the distraction level 62 exceeds the threshold 64, and the warning 68 is issued to the driver. This prompts the driver to perform an input and / or driving action that increases their attention; this is marked with an "X" in diagram 44. Since it is not a similar input and / or driving action, the dead time 54a has no effect, and the attention-enhancing input and / or driving action is taken into account.

[0047] In particular, the dwell time 58 is preferably ignored at the point marked with "X". Because a distracted driver was previously detected, and this driver then performed an action that increased their attention, and the distraction level remains in the distracted range even after this action, the driver's level of distraction can no longer be unambiguously determined. The index is continuously reduced to a neutral level of attention 66 according to a gradient. This procedure is also applied if the driver was previously attentive, performs a distracting action, and the distraction level still indicates an attentive driver. However, if the distraction level changes ranges, the driver's level of distraction can preferably be unambiguously determined, and the dwell time can be evaluated.

[0048] A further input or action that increases attention leads to a further reduction in the determined distraction level 62, indicating increased driver attention. Due to the reduced distraction level 62, the last input or action that significantly reduces attention is insufficient to again exceed the threshold 64 and trigger a warning 68 to be displayed to the driver. Since no further inputs or actions occur, the distraction level 62 steadily returns to a neutral attention level 66 after the dwell time 58 has elapsed.

[0049] In Figure 6 The steps of a method according to the invention for estimating a degree of distraction 62 of a driver while driving in a motor vehicle 30, preferably by means of a device 10 as described above, and / or a system 18 as described above, are shown schematically.

[0050] In a first step S1, driver data is received, including operating and sensor data with information about the driver's behavior while driving. In a second step S2, the driver's distraction level 62 is determined based on this driver data. Subsequently, in a third step S3, a control command is transmitted to an output unit 20, which triggers the output of a warning 68 to the driver if the determined distraction level 62 exceeds a predefined threshold 64, thus alerting the driver to an increased distraction level 62. This warning can be based on predefined driver behavior during driving, indicating an increase and / or decrease in the distraction level 62.

[0051] The invention has been described in detail. It is understood that the individual features can be combined not only as described in the exemplary embodiments but also in other ways. Furthermore, a person skilled in the art will recognize that the disclosed teaching can readily be transferred to areas where machines are guided or operated by user input. Reference symbol list

[0052] 10 Device 12 Input interface 14 Analysis unit 16 Output interface 18 System 20 Output unit 22 Primary vehicle guidance devices 24 Steering wheel 26 Steering angle sensor 28 Camera 30 Motor vehicle 32 Pedal assembly 34 Shift unit 36 ​​Mirror adjustment control unit 38 Electric window control unit 40 Center display control unit 42 Instrument cluster control unit 44 Diagram 46 Diagram 48 Diagram 50 Circle 52 Y-axis 54 Dead time 56 Y-axis 58 Hold time 60 Y-axis 62 Distraction level 64 Threshold 65 Maximum value 66 Neutral attention level 68 Note S1 to S3 Procedure steps

Claims

1. Device (10) for estimating the degree of distraction (62) of a driver during a journey in a motor vehicle (30), comprising: - an input interface (12) for receiving driver data including operating data and sensor data containing information regarding the behavior of the driver during the journey; - an analysis unit (14) for determining a variable degree of distraction (62) of the driver based on driver data, - an output interface (16) for transmitting a control command to an output unit (20), which command causes an alert (68) to be output to the driver when the analysis unit (14) detects a degree of distraction (62) that is greater than a predefined threshold value (64) in order to alert the driver to an increased degree of distraction (62), characterized in that the degree of distraction (62) is represented by an index that indicates the current state of attention of the driver and has a neutral degree of attention (66) as a reference value, it being possible for the index to take on values which indicate a higher level of attention than the neutral degree of attention (66), as well as values which indicate a lower level of attention than the neutral degree of attention (66), the analysis unit (14) being designed to detect, based on a predefined behavior of the driver during the journey, an increase and, based on a predefined behavior of the driver during the journey, a decrease in the degree of distraction (62) and to adjust the index accordingly, and in that the analysis unit (14) is designed to continuously reduce the index according to a gradient to the neutral degree of attention (66) when no predefined behavior of the driver which indicates an increase or decrease in the degree of distraction (62) is identified over a parameterizable time.

2. Device (10) according to claim 1, characterized in that the operating data comprise information regarding the activation of an operator control apparatus in the region of a driver task area, in particular an operating unit of a central display (40) and / or a center console, an operating unit of a multifunction steering wheel, an operating unit for adjusting mirrors (36), an operating unit for adjusting seats, an operating unit for an electric window lifter (38), an operating unit for adjusting the interior light and / or an operating unit for adjusting the roof window.

3. Device (10) according to any of the preceding claims, characterized in that the operating data comprise information relating to the operation of devices for primary vehicle control (22), in particular a pedal assembly (32) and / or a steering wheel position; and / or the sensor data comprise information relating to a driving behavior of the motor vehicle (30), in particular an acceleration behavior of the motor vehicle (30), and / or information relating to the driver, in particular observation of the driver by a camera (28).

4. Device (10) according to any of the preceding claims, characterized in that the analysis unit (14) is designed to determine a warning time based on data fusion of the operating data and sensor data, the control command causing an alert (68) to be output to the driver at the warning time.

5. Device (10) according to any of the preceding claims, characterized in that the analysis unit (14) is designed to assign an expected, preferably weighted, driver distraction to an operating input and / or a driver action of the driver, in particular the analysis unit (14) being designed to parameterizably assign an attention level potential to each driver distraction in order to determine an effect of the driver distraction on the degree of distraction (62) of the driver.

6. Device (10) according to any of the preceding claims, characterized in that the analysis unit (14) is designed to assign a hold time (58) to a driver distraction, which hold time corresponds to the duration of the distraction of the driver caused by and / or as a result of an operating input and / or a driver action.

7. Device (10) according to any of the preceding claims, characterized in that the analysis unit (14) is designed to assign the expected driver distraction of a single operating input and / or driver action to a plurality of consistent operating inputs and / or driver actions within a predefined downtime (54).

8. System (18) for estimating the degree of distraction (62) of a driver during a journey in a motor vehicle (30), comprising: a device (10) according to any of the preceding claims; and an output unit (20) for outputting an alert (68) to the driver when the analysis unit (14) detects a degree of distraction (62) that is greater than a predefined threshold value (64) in order to alert the driver to an increased degree of distraction (62).

9. Method for estimating the degree of distraction (62) of a driver during a journey in a motor vehicle (30), preferably by means of a device (10) according to any of claims 1 to 7 and / or a system (18) according to claim 8, comprising the steps of: - receiving (S1) driver data comprising operating data and sensor data comprising information regarding the behavior of the driver during the journey; - determining (S2) a degree of distraction (62) of the driver based on the driver data, - transmitting (S3) a control command to an output unit (20) which causes an alert (68) to be output to the driver when a determined degree of distraction (62) is greater than a predefined threshold value (64) in order to alert the driver to an increased degree of distraction (62), characterized in that the degree of distraction (62) is represented by an index which indicates the current state of attention of the driver and has a neutral degree of attention (66) as a reference value, it being possible for the index to take on values which indicate a higher level of attention than the neutral degree of attention (66), as well as values which indicate a lower level of attention than the neutral degree of attention (66), based on a predefined behavior of the driver during the journey, an increase and, based on a predefined behavior of the driver during the journey, a decrease in the degree of distraction (62) is detected and the index is adjusted accordingly, and the index is continuously reduced according to a gradient to the neutral degree of attention (66) when no predefined behavior of the driver which indicates an increase or decrease in the degree of distraction (62) of the driver is identified over a parameterizable time.

10. Computer program having program code means for carrying out all steps of a method according to the preceding claim 9 when the computer program is executed on a computer or a corresponding computing unit.