Apparatus and method for detecting distraction of a driver of a vehicle

Description

[0001] The present invention relates generally to the detection of distraction of an individual, particularly in a vehicle.

[0002] It relates more particularly to a device and a method for detecting distraction of a driver of a vehicle.

[0003] It is known to monitor the driver of a motor vehicle using a monitoring device adapted to determine the driver's state of alertness and in particular to prevent him from falling asleep at the wheel. Depending on the determined state of alertness, the monitoring device alerts the driver to prevent him from putting himself in a dangerous situation.

[0004] Such a monitoring device infers the driver's state of alertness based on behavioral parameters associated with the driver and / or vehicle operating parameters. In practice, the behavioral parameters, for example the rate of eyelid closure or the direction of gaze, are obtained by analyzing images of the driver's head, and the vehicle operating parameters, for example parameters relating to a steering wheel rotation angle, a vehicle speed or the driver's action on certain keys, are obtained from physical sensors of the vehicle.

[0005] Detection systems are also known that are adapted to assess driver distraction, for example based on the driver's direction of gaze. Thus, the driver is considered not to be distracted when looking at the road or his or her interior rearview mirror. The driver is considered distracted when looking in a direction other than that of the road and the organs necessary for driving, for example, the front passenger side. Document US10013620B1 describes an on-board system intended to monitor drivers and passengers inside vehicles via sensors and cameras. It allows image data to be automatically compressed by removing those deemed redundant. The data collected (positions of the head, hands, seat belt, telephone, etc.) are used to assess the insurance risk based on the driver's behavior.The driver's hands are tracked by onboard cameras that analyze their position, movements, and the objects held, using skeletal models. This data makes it possible to assess the driver's distraction or attention.

[0006] These driver distraction detection systems have the advantage of estimating whether a driver is distracted while a vehicle is in operation and thus significantly improve driver safety conditions.

[0007] In order to improve driver distraction detection systems, the present invention provides a device for detecting distraction of a driver of a vehicle.

[0008] More particularly, the invention provides a device for detecting distraction of a driver of a vehicle comprising: an image acquisition assembly adapted to acquire at least one image of a detection zone located in said vehicle, said detection zone comprising at least a part of the driver of the vehicle, a module for processing the acquired image designed to determine: a direction associated with the driver's head, and a position of at least one hand of the driver, and an analysis module designed to detect the distraction of said driver by determining, on the basis of the direction associated with the head and the position of at least one hand, the possible presence of at least one hand in the direction associated with the driver's head.

[0009] Thus, the device of the invention makes it possible to determine whether a driver's attention is focused on his hand, and therefore possibly on an object that he is holding in his hand and which could potentially compromise his safety by distracting him from the road.

[0010] Other non-limiting and advantageous characteristics of the detection device according to the invention, taken individually or in all technically possible combinations, are as follows: there is also provided a module for measuring a time designed to evaluate a detection time during which at least one hand is located in said direction associated with the head determined by the processing module; there is also provided a module for transmitting an alarm signal depending on the detection of a distraction situation; the distraction situation corresponds to a configuration in which at least one hand of the driver is located outside at least one authorized zone; the distraction situation comprises a configuration in which the detection time is greater than a predetermined threshold; the transmitting module is designed to transmit the alarm signal in the case of a vehicle driving condition; the driving condition corresponds to the detection of a vehicle speed greater than a predetermined speed value or to the absence of use of an autonomous driving unit;the processing module is also designed to determine a posture of the driver; the processing module of the acquired image is designed to determine the direction associated with the driver's head and the position of at least one hand of the driver on the basis of a representation of the driver's posture; the processing module is designed to determine a direction of orientation of the head or a direction of gaze of the driver. ;

[0011] The invention also provides a method for detecting distraction of a driver of a vehicle comprising steps of: acquiring at least one image of a detection zone located in said vehicle, said detection zone comprising at least a part of the driver of the vehicle, determining a direction associated with the driver's head, determining a position of at least one hand of the driver, and detecting the distraction of said driver by comparing the direction associated with the head and the position of at least one hand determined to determine the possible presence of at least one hand in the direction associated with the driver's head.

[0012] The method may also include steps of: measuring a detection time during which at least one hand is located in said direction associated with the head determined by a processing module, and emitting an alarm signal as a function of the detection of a distraction situation.

[0013] The description which follows with reference to the appended drawings, given as non-limiting examples, will make it clear what the invention consists of and how it can be implemented.

[0014] On the attached drawings: [ Fig. 1 ] schematically represents a front view of a motor vehicle equipped with a device for detecting driver distraction in accordance with the invention, [ Fig. 2 ] represents an example of a device for detecting driver distraction in accordance with the invention, [ Fig. 3 ] represents, in the form of a flowchart, a first example of a method for detecting driver distraction in accordance with the invention, and [ Fig. 4 ] represents, in the form of a flowchart, a second example of a method for detecting driver distraction in accordance with the invention.

[0015] On the figure 1 , the front of a motor vehicle 1 (also called “vehicle 1” hereinafter) is shown, carrying a device 10 for detecting the distraction of a driver 4 of the vehicle 1.

[0016] More specifically, such a distraction detection device 10 is adapted to determine the state of distraction of the driver 4 as a function of the determination of a posture of the driver 4 in the vehicle 1. The posture thus determined makes it possible to deduce in particular the position of the head and of at least one hand of the driver in order to know whether the driver 4 is concentrating on his driving or on the contrary is distracted.

[0017] In this description, the driver 4 is considered to be distracted if he does not focus his attention on the road, nor on a rearview mirror (for example a right rearview mirror 6 or a left rearview mirror 7 or a central rearview mirror 8) or on a driving device such as a steering wheel 3 or a gear lever 2. On the contrary, the driver 4 is for example considered to be distracted if he focuses his attention on the front passenger or on an object not useful for driving. For example, in the case shown in the figure 1 , the driver holds an object 20 in one hand, here a mobile phone.

[0018] As visible on the figure 2 , the distraction detection device 10 comprises an image acquisition assembly 22, a processing module 24 for at least one acquired image, an analysis module 26, a time measurement module 28 and a transmission module 30 for an alarm signal.

[0019] The image acquisition assembly 22 is installed in the vehicle 1, more precisely in the passenger compartment of the vehicle 1. The image acquisition assembly 22 is adapted to acquire at least one image inside the vehicle 1.

[0020] In particular, the image acquisition assembly 22 is adapted to acquire an image of a detection zone D located inside the vehicle 1. As shown in the figure 1 , the detection zone D extends between the gear lever 2 and the front door of the vehicle 1 (not visible on the figure 1 ). This detection zone D therefore includes the steering wheel 3 and at least part of the driver 4. In practice, the head and at least one hand of the driver are located in the detection zone D.

[0021] The image acquisition assembly 22 comprises for example at least one three-dimensional sensor 21 making it possible to capture a three-dimensional image of the detection zone D and in particular of the driver 4 of the vehicle 1. As a variant, the image acquisition assembly 22 may also comprise a two-dimensional sensor 23. The two-dimensional sensor 23 is for example adapted to capture an image of the face of the driver 4, and in particular of his eyes.

[0022] In practice, to capture images of the detection zone D, the three-dimensional sensor 21 is for example positioned in a front ceiling light of the vehicle 1, so that it takes a top view of the detection zone D. The two-dimensional sensor 23 is for example arranged in a lower part of the windshield of the vehicle 1, substantially opposite the driver 4.

[0023] Alternatively, the three-dimensional 21 and two-dimensional 23 sensors can be placed on a dashboard of the vehicle 1, in a central area of the latter.

[0024] As shown in the figure 2 , the distraction detection device 10 also comprises the processing module 24 of the image acquired by the image acquisition assembly 22. The processing module 24 is designed to receive the acquired images and determine a posture of the driver 4 in the vehicle 1.

[0025] In particular, the processing module 24 is designed to determine, from the processing of the acquired images, a representation of the posture of the driver. By representation of the posture of the driver 4, we mean the location and position of different members of the body of the driver 4, in particular the head and hands of the driver 4.

[0026] In practice, from this representation of the posture, the processing module 24 is designed to determine a direction associated with the head of the driver 4. By direction associated with the head, is meant for example here a direction of overall orientation of the head or a direction of an element of the driver's head. In the example described here, the direction associated with the head comprises the direction of orientation of the head or the direction of gaze of the driver 4. In particular, the processing module 24 is here designed to determine a direction of orientation of the head of the driver 4. The processing module 24 is also designed to determine the position of at least one hand of the driver 4 as a function of the representation of the posture. The processing module 24 is also designed to determine a direction of gaze of the driver 4 when images are acquired by the two-dimensional sensor 23.

[0027] The distraction detection device 10 also comprises the analysis module 26. The analysis module 26 is designed to determine, from the direction of orientation of the head and the position of the hands determined by the processing module 24, the possible presence of at least one hand in the direction of orientation of the head of the driver 4. In other words, the analysis module 26 determines whether the head of the driver 4 is directed towards one of his hands (or towards both). Alternatively, the analysis module 26 can determine whether the gaze of the driver 4 is directed towards one of his hands.

[0028] As visible on the figure 2 , the distraction detection device 10 comprises a time measurement module 28. This time measurement module 28 is designed to evaluate a detection time during which at least one hand is located in the direction of orientation of the head of the driver 4. In other words, the time measurement module 28 evaluates the time (hereinafter called detection time) during which the head of the driver 4 remains directed towards at least one of his hands. Alternatively, the time measurement module 28 can evaluate the time during which the driver's gaze remains directed towards at least one of his hands.

[0029] The distraction detection device 10 finally comprises a module 30 for transmitting an alarm signal. The module 30 for transmitting an alarm signal is designed to transmit an alarm signal when a distraction situation is detected. By distraction situation, we mean for example the location of at least one hand of the driver 4 outside an authorized zone (described below) or the measurement of the detection time greater than a predetermined threshold (also described below).

[0030] The invention also relates to a method for detecting the distraction of a driver 4 of the vehicle 1 by using the detection device 10 described above.

[0031] This method can be advantageously used, for example, to determine whether driver 4 is distracted by an object he is holding in one of his hands, for example a mobile phone.

[0032] There figure 3 represents a first example of implementation of a method for detecting distraction of the driver 4 of the vehicle 1, illustrated in the form of steps.

[0033] As shown in the figure 3 , the method begins at step E2. During this step, at least one image of the detection zone D is acquired by the three-dimensional sensor 21 of the image acquisition assembly 22. The acquired image includes in particular the head and at least one hand of the driver 4.

[0034] In step E4, the image acquired in step E2 is processed by the processing module 24 in order to determine the posture of the driver. In practice, the processing module 24 determines, from the acquired image (here three-dimensional as indicated previously), a representation of the posture of the driver. In other words, the processing module 24 makes it possible to determine the position of different elements of the body of the driver 4 and in particular the position of the head and at least one hand of the driver 4.

[0035] The processing module 24 then determines, from the representation of the posture of the driver 4 and therefore by analysis of the acquired images, the direction of orientation of his head and the position of at least one of his hands (step E6).

[0036] The method then continues in step E8. In this step, the analysis module 26 uses the position of the hands determined in step E6 to determine whether the hands are located in at least one authorized zone. An authorized zone for the position of the hands is defined from the zones in which the hands are placed while driving a vehicle. For example, here, an authorized zone may include the gear lever 2, the steering wheel 3, elements for adjusting the ventilation of the passenger compartment or any other driving or adjustment member useful to the driver 4 while driving. In the example of the figure 1 , the driver's left hand is positioned on the steering wheel 3 and is therefore in the authorized zone as defined previously. On the other hand, the right hand is holding a mobile phone 20 and is not in the authorized zone.

[0037] In the method according to the invention, if both hands are in the authorized zone, the method continues at step E2. If one or both hands are outside the authorized zone, the method continues at step E10.

[0038] In step E10, the analysis module 26 determines the possible presence of the hand located outside the authorized zone in the direction of orientation of the head of the driver 4. In other words, the analysis module 26 determines whether the head of the driver 4 is oriented towards one of his hands.

[0039] If the head of driver 4 is not facing the hand located outside the authorized zone, the process resumes at step E2.

[0040] Otherwise, as visible on the figure 3 , the method continues at step E12. During this step, the time measurement module 28 measures the detection time during which the head of the driver 4 remains directed towards his hand, that is to say the time during which the hand is located in the determined orientation direction.

[0041] This detection time is then compared to a predetermined threshold (step E14). This predetermined threshold corresponds, for example, to a maximum time during which the driver 4 could divert his attention from the road without entailing danger to his safety. In practice, this predetermined threshold is here between 1 second (s) and 3 s, for example of the order of 2 s. This predetermined threshold could, for example, be a function of the speed of the vehicle 1.

[0042] If the detection time is less than this predetermined threshold, the driver is not considered to be distracted and the process resumes at step E2.

[0043] On the other hand, if the detection time is greater than or equal to the predetermined threshold, the method continues with steps E16 and E18. During these steps, the analysis module 26 determines whether the driver is in driving condition. In particular, the driver is in driving condition if an autonomous driving unit 50 is not used or if the speed of the vehicle 1 is greater than a predetermined speed value.

[0044] In step E16, the analysis module checks, for example, whether the autonomous driving unit 50 is being used. If this is the case, the driver 4 is not considered to be distracted from his driving since the autonomous control unit assists him. The method then resumes at step E2.

[0045] If the autonomous driving unit 50 is not used, the method continues at step E18. During step E18, the speed of the vehicle 1 is compared to the predetermined speed value. The predetermined speed value is for example very low; step E18 then makes it possible to determine whether the vehicle is stationary. If the speed of the vehicle 1 is lower than this predetermined value, the driver 4 is not considered to be in driving condition (and therefore his state of distraction does not need to be controlled). The method resumes at step E2.

[0046] If the speed of the vehicle 1 is greater than the predetermined value, the driver 4 is considered to be in driving condition and must not be distracted. An alarm signal is then emitted in step E20 by the transmission module 30. The alarm signal emitted following the detection of the distraction of the driver 4 is for example specific, in particular by being more emphatic than a conventional alarm signal (of the type for example of the signal emitted in the event of a low fuel level). The alarm signal emitted during step E20 is for example of the type of signal emitted when the driver has not fastened his seat belt, that is to say an intermittent signal whose intensity and frequency increase as long as the belt is not fastened. Here, the intensity and frequency of the alarm signal could increase until the driver 4 diverts his attention from the object he is holding in his hand.

[0047] There figure 4 represents a second example of implementation of the method for detecting the distraction of a driver 4 of the vehicle 1, illustrated in the form of steps.

[0048] As shown in the figure 4 , the method begins at step E42. During this step, at least one image of the detection zone is acquired by the three-dimensional sensor 21 of the image acquisition assembly 22. The acquired image comprises in particular the head and at least one hand of the driver 4. Simultaneously, another image is also acquired by the two-dimensional sensor 23 of the image acquisition assembly 22. This other image comprises for example the face of the driver 4.

[0049] In step E44, the image acquired in step E42 is processed by the processing module 24 in order to determine the posture of the driver (in a similar manner to step E4 described previously). During this step E44, the other image is also processed in order to determine a position of the head and a direction of gaze of the driver 4 (this direction of gaze being, as already indicated, an example of a direction associated with the head of the driver).

[0050] At the end of step E44, the processing module 24 has therefore determined the representation of the posture of the driver 4 and his direction of gaze.

[0051] The processing module 24 then determines, from the representation of the posture of the driver 4, the position of at least one of his hands (step E46 similar to step E6 previously described). Alternatively, the direction of orientation of the head of the driver 4 may possibly be determined from the representation of the posture of the driver 4 in order to be combined with the direction of gaze of the driver 4.

[0052] The method then continues in step E48. In this step, as in step E8, the analysis module 26 uses the position of the hands determined in step E46 to determine whether the hands are located in the authorized zone.

[0053] In the method according to the invention, if both hands are in the authorized zone, the method continues at step E42. If one or both hands are outside the authorized zone, the method continues at step E50.

[0054] In step E50, the analysis module 26 determines the possible presence of the hand located outside the authorized zone in the direction of orientation of the head of the driver 4. In particular, the analysis module 26 determines whether the gaze of the driver 4 is oriented towards one of his hands. This evaluation makes the detection of the distraction of the driver 4 more precise (compared to the use of the direction of orientation of the head) because the determination of the gaze detection makes it possible to know where the attention of the driver 4 is actually directed.

[0055] If the gaze of driver 4 is not directed towards the hand located outside the authorized zone, the process resumes at step E42.

[0056] Otherwise, as visible on the figure 4, the method continues at step E52. As in step E12, the time measurement module 28 measures the detection time during which the driver's head remains directed towards his hand, i.e. the time during which the hand is located in the determined direction of gaze.

[0057] This detection time is then compared to a predetermined threshold (step E54).

[0058] If the detection time is less than this predetermined threshold, the driver is not considered to be distracted and the process resumes at step E42.

[0059] On the other hand, if the detection time is greater than or equal to the predetermined threshold, the method continues with steps E56 and E58 (similar to steps E16 and E18). During these steps, the analysis module 26 determines whether the driver is in driving condition. In particular, the driver is in driving condition if an autonomous driving unit 50 is not used or if the speed of the vehicle 1 is greater than a predetermined speed value.

[0060] In step E56, the analysis module checks, for example, whether the autonomous driving unit 50 is being used. If this is the case, the driver 4 is not considered to be distracted from his driving since the autonomous control unit assists him. The method then resumes at step E42.

[0061] If the autonomous driving unit 50 is not used, the method continues at step E58. During step E58, the speed of the vehicle 1 is compared to the predetermined speed value. If the speed of the vehicle 1 is lower than this predetermined value, the driver 4 is not considered to be in driving condition (and therefore his state of distraction does not need to be controlled). The method continues at step E42.

[0062] If the speed of the vehicle 1 is greater than the predetermined value, the driver is considered to be in driving condition and must not be distracted. Just as in step E20 described previously, an alarm signal is then emitted in step E60 by the transmission module 30.

Claims

1. Device (10) for detecting distraction of a driver (4) of a vehicle (1) comprising : - an image acquisition assembly (22) adapted to acquire at least one image of a detection zone (D) located in said vehicle (1), said detection zone (D) comprising at least part of the driver (4) of the vehicle (1), - an acquired image processing module (24) designed to determine : a direction associated with the head of the driver (4), and a position of at least one hand of the driver (4), - a emission module (30) for emitting an alarm signal based on the detection of a distraction situation, and - an analysis module (26) designed to detect distraction of the said driver (4) by determining, on the basis of the direction associated with the head and the position of at least one hand, the possible presence of at least one hand in the direction associated with the head of the driver (4) characterised in that the distraction situation corresponds to a configuration in which at least one hand of the driver (4) is located outside at least one authorised zone defined from the zones in which the hands rest while driving a vehicle, the device also comprising a time measurement module (28) designed to evaluate a detection time during which at least one hand is located in said direction associated with the head determined by the processing module (24), the distraction situation comprising a configuration in which the detection time is greater than a predetermined threshold.

2. Device (10) according to claim 1, wherein the emission module (30) is designed to emit the alarm signal in the event of a driving condition of the vehicle (1).

3. A device (10) according to claim 2, wherein the driving condition corresponds to the detection of a vehicle speed greater than a predetermined speed value or to the absence of use of an autonomous driving unit (50).

4. Device (10) according to any one of claims 1 to 3, wherein the processing module (24) is also designed to determine a posture of the driver (4).

5. Device (10) according to claim 4, in which the acquired image processing module (24) is designed to determine the direction associated with the head of the driver (4) and the position of at least one hand of the driver (4) on the basis of a representation of the posture of the driver (4).

6. Device (10) according to any one of claims 1 to 5, in which the processing module (24) is designed to determine a direction of orientation of the head or a direction of gaze of the driver (4).

7. A method of detecting distraction of a driver (4) of a vehicle (1) comprising the steps of : - acquiring at least one image of a detection zone (D) located in said vehicle (1), said detection zone (D) comprising at least part of the driver (4) of the vehicle (1), - determination of a direction associated with the head of the driver (4), - determining a position of at least one hand of the driver (4), - emitting an alarm signal as a function of the detection of a distraction situation - detecting distraction of said driver (4) by comparing the direction associated with the head and the position of at least one hand determined to determine the possible presence of at least one hand in the direction associated with the head of the driver (4) characterised in that the distraction situation corresponds to a configuration in which at least one hand of the driver (4) is located outside at least one authorised zone defined from the zones in which the hands rest while driving a vehicle, the method also comprising the steps of : - measuring a detection time during which at least one hand is located in said direction associated with the head determined by a processing module (24), and - emitting an alarm signal as a function of the detection of a distraction situation.