FR3119479A1 - Determination of driver fatigue status in a controlled environment - Google Patents

Abstract

The invention relates to a method for verifying the state of fatigue of a driver of a vehicle comprising the storage (200) of reference physiological data in a memory and the verification (202) that an environment of the driver is in a given reference state. When the driver's environment is in the given reference state, obtaining (203) current physiological data of the driver, the method includes comparing (206) the current physiological data with the reference physiological data and determining (206) of a fatigue state of the driver as a function of the comparison FIG. 2

Description

Determination of driver fatigue status in a controlled environment

The present invention belongs to the field of the control of motor vehicle drivers, in particular professional drivers. It relates in particular to a method and a device for monitoring the state of fatigue of a driver.

It is particularly advantageous in the case where the control is prior to starting the vehicle

“Vehicle” means any type of vehicle such as a motor vehicle, moped, motorcycle, warehouse storage robot, etc.

Before starting a vehicle, the regulations of some countries require the driver to make a self-declaration of their state of fatigue. This is particularly the case for professional drivers, taxis or personal drivers. In case of too intense fatigue, the driver cannot work.

Such a self-assessment is then transmitted to a centralized server of a control center, so as to follow the driver during his professional mission and possibly switch him to a rest period or an alternative mission.

Otherwise, when the level of fatigue is low enough, the driver can start the vehicle in order to begin his professional mission.

Driver monitoring systems, called “Driver Monitoring Systems”, DMS, in English are known.

However, such systems are activated during the driving operation, and do not make it possible to check beforehand, before the driving operation, the state of fatigue of the driver.

In addition, a DMS requires a learning phase to calibrate the software on which it is based, which cannot be achieved the first time the driver gets into the vehicle at the start of a working day.

A self-declaration concerning the state of fatigue of a professional driver is often poorly informed, even knowingly erroneous, since the car driver has a financial incentive to carry out his professional mission.

Inside the vehicle, when rudimentary physiological data is collected, it is most often of poor quality, and it is very difficult to accurately monitor the evolution of the driver's state of fatigue. The risk of error associated with diagnosis is therefore high, which creates significant safety issues for the driver.

Inaccuracies in the driver's physiological data may be due to:

- changes in ambient light (cabin light, sunlight, approaching car traffic, entering or exiting a tunnel or parking lot. Such changes have an impact on blinking of the eyes, dilation of the pupils, perspiration, stress, and other physiological data;

- variations in temperature, from hot to cold or cold to hot, which affects perspiration, blood pressure, respiration, vasomotricity and other physiological data.

Therefore, the techniques of the prior art are based:

- either on subjective data;

- or on objective physiological data of lesser quality.

Thus, it is not possible to obtain clear and exact information on the state of fatigue of the driver in order to monitor, coordinate and protect the driver.

As for driver monitoring cameras, they can measure the driver's distraction but require calibration to the driver, which is complicated when the car is static and the driver appears for the first time in front of the camera.

The present invention improves the situation.

To this end, a first aspect of the invention relates to a method for checking the state of fatigue of a driver of a vehicle comprising the following steps, prior to starting the vehicle:

- storage of reference physiological data in a memory;

- verification that a driver's environment is in a given reference state;

- when the driver's environment is in the given reference state, obtaining current physiological data of the driver;

- comparison of current physiological data with reference physiological data;

- determination of a state of fatigue of the driver as a function of the comparison .

By ensuring that the driver's environment corresponds to a predefined state, the quality of the physiological data collected is improved and the reliability associated with determining the state of driver fatigue is improved.

According to one embodiment, when the driver's environment is not in the given reference state, the method may further comprise:

- the display of a message for the driver indicating to modify one or more current vehicle data representative of the driver's environment; Or

- the automatic modification of current vehicle data representative of the driver's environment.

Thus, it is possible to rectify the driver's environment so that it corresponds to the reference state. Thus, physiological data is always collected in a similar context, which improves the reliability associated with determining the state of driver fatigue.

According to one embodiment, the method may further comprise a step of controlling the starting of the vehicle according to the determined state of fatigue.

Thus, safety is improved, in that starting of the vehicle is prevented when the state of fatigue of the driver does not allow him to drive with a sufficient level of safety.

According to one embodiment of the invention, the method may further comprise a step of adapting a route or a driving program to the state of fatigue of the driver.

Thus, when the driver is tired, the journey offered to him can be adapted, for example by adding break times or by shortening the overall journey time.

According to one embodiment, the physiological data of the driver can be stored in association with a user identifier, and can include, prior to the verification of the driver's environment, a driver identification step.

Indeed, each driver has different physiological reference data. Thus, the same memory can store the physiological data of several conductors.

According to one embodiment of the invention, the step of verifying that the driver's environment is in a reference state comprises comparing current vehicle data with reference vehicle data.

Thus, it is ensured that the physiological data is collected in a stable and predefined environment.

In addition, the reference vehicle data may include at least one of the following elements:

- a vehicle reference speed;

- reference lighting for a vehicle cabin;

- reference settings for a heating and ventilation system;

- reference infotainment settings;

- one or more reference location zones of the vehicle; and or

- a reference moment or a reference time slot.

Such vehicle data ensures that the driver's environment allows the acquisition of reliable physiological data.

According to one embodiment, the reference physiological data may comprise at least one of the following elements:

- a reference weight;

- a reference blood pressure;

- a reference heart rate; and or

- reference electroencephalogram measurements.

Thus, the physiological data collected is representative of the driver's state of fatigue.

A second aspect of the invention relates to a computer program comprising instructions for implementing the method according to the first aspect of the invention, when these instructions are executed by a processor.

A third aspect of the invention relates to a device for controlling a driver of a vehicle comprising:

- a reference physiological data storage memory or an interface for accessing a physiological data storage memory;

- a processor configured for:

verify that a driver's environment is in a given reference state;

when the driver's environment is in the given reference state, obtaining current physiological data of the driver;

comparing current physiological data with the reference physiological data;

determining a fatigue state of the driver based on said comparison.

Other characteristics and advantages of the invention will appear on examination of the detailed description below, and of the appended drawings in which:

illustrates a system according to one embodiment of the invention;

is a diagram illustrating the steps of a method according to one embodiment of the invention;

illustrates a vehicle driver control system according to one embodiment of the invention;

There presents a system according to one embodiment of the invention.

The system includes a vehicle 100 including a driver monitoring device 110, or DMS.

The DMS 110 can be connected to at least one physiological sensor 111. No restriction is attached to the physiological sensor, which can be any device capable of acquiring physiological data from the driver of the vehicle 100. By way of example, the physiological sensor 111 can be an electroencephalogram, a device able to measure the tension or the pulse of the driver, a temperature sensor of the driver or any other sensor able to obtain physiological data representative of a state of fatigue of the driver.

The vehicle 100 may further comprise an on-board camera 112, such as a driver monitoring camera, called “On Board Driver Monitoring Camera”. The camera 112 is able to obtain video data or photos of the driver of the vehicle 100.

The vehicle 100 can further comprise a first on-board device 113 and a second on-board device 114. Each on-board device is capable of modifying the internal or external environment of the vehicle 100. No restriction is attached to the number or type of on-board device that vehicle 100 includes. For example, vehicle 100 may include a radio, a lighting system, a ventilation system, or a heating system.

The vehicle 100 may also comprise a GPS module 116, for " Global Positioning System " able to acquire position data of the vehicle 100, in particular by satellite.

The vehicle 100 may further comprise a man-machine interface, HMI, 119, able to provide the interface between the driver and the vehicle 100, and in particular with the DMS 110. The HMI 119 is in particular able to receive data from input from a user of the vehicle 100. No restriction is attached to the HMI 119 which can be a set of mechanical buttons, a touch screen or capacitive or resistive touch keys. Preferably, the HMI 1119 comprises a display screen making it possible to display data for the attention of the driver. No restriction is attached to the technology of such a screen.

The vehicle 100 can further comprise a first interface 117, capable of accessing one or more remote servers. Preferably, the first interface 117 is a wireless interface, such as an interface capable of accessing a cellular network such as a 4G, 5G network or any subsequent generation.

The cellular network can allow access to an extended data network such as the Internet network for example, via which the communication interface 117 can access a first server 120 and a second server 121.

The first server 120 may be a server storing vehicle data, such as a vehicle identifier in association with vehicle characteristics or with driver identifiers. No restriction is attached to vehicle characteristics which may include a model, a list of vehicle equipment such as devices 113 and 114, camera 112, and sensor(s) 111.

According to the invention, the first server 120 may further comprise reference vehicle data stored in association with a vehicle identifier such as the vehicle identifier 100. No restriction is attached to the format of the vehicle identifier 100. In addition, no restriction is attached to the reference vehicle data, which may include one or more of the following data:

- a reference speed: 0 km/h for example, i.e. the vehicle stationary;

- reference lighting: stable low-intensity lighting, for example in the shadow of a building;

- reference settings for the heating and ventilation system: for example 25°C with weak and indirect ventilation, for example in the direction of the windscreen, in order to avoid ventilating the driver's face;

- reference infotainment settings: off status of the radio and other infotainment systems;

- one or more reference location areas of the vehicle: for example, anywhere the noise level is low, away from highways, or any other reference state;

- a reference time: for example, a schedule in the morning.

As a variant, the reference vehicle data are intervals of values, obtained for example from statistical distributions. For example, the reference moment can be replaced by a reference time range.

Other reference vehicle data may be stored in the first server 120.

Alternatively, instead of being stored in the first server 120, the reference vehicle data can be stored locally in the memory 115 or in a memory internal to the DMS 110.

The second server 121 may be a server storing personal data, such as driver data. According to the invention, the second server 121 can in particular store reference physiological data. Reference physiological data means any data indicative of a so-called normal physiological state of the driver. Such a normal state may in particular correspond to a low level of fatigue.

The baseline physiological data may include one or more of the following data:

- a reference weight;

- a reference blood pressure;

- a reference heart rate

- reference electroencephalogram measurements;

- a reference body temperature;

- any other physiological reference data.

As a variant, the reference physiological data are intervals of values, obtained for example from statistical distributions of the data.

The system may further include one or more user devices, such as a first user device 130 and a second user device 131.

The user devices 130 and 131 can communicate with the DMS 110 and more generally with the vehicle 100, via a second interface 118. No restriction is attached to the second interface, which can be a short or medium range interface such as a Wifi or Bluetooth interface.

Furthermore, the user devices 130 and 131 can communicate with the second server 121, via an extended network of the Internet type for example.

User device means any device capable of acquiring data relating to the driver, such as physiological data or activity data. The data collected can be used to determine baseline physiological data. User devices can for example be connected objects such as:

- a connected scale capable of acquiring and transmitting weight data from a user to the second server 121 or to the DMS 110 for local storage;

- a diary connected to list activities such as sports sessions, work, etc., and capable of transmitting this data to the second server 121 or to the DMS 110 for local storage for example;

- a connected bracelet or a connected watch capable of acquiring and transmitting activity data, such as a number of steps, quality of sleep, sports activity, heart rate, body temperature;

- a blood pressure measuring device able to acquire and transmit blood pressure data of the driver.

There is a diagram illustrating the steps of a method according to one embodiment of the invention.

At a prior step 200, the driver's physiological reference data is stored in a memory, in association with a user identifier. Such a memory can be a memory of the DMS 110, a memory of the second server 121 or the memory 115 of the vehicle 100. The reference vehicle data can also be stored at a step prior to steps 201 and following.

At a step 201, the driver of the vehicle is identified with the vehicle 100. For example, the driver is identified when he enters the vehicle, before starting the vehicle 100. No restriction is attached to the way in which the driver of the vehicle is identified. For example, the identification may comprise the selection of an identifier by the driver, for example via the HMI 119, the acquisition of biometric data from the driver, or any other method allowing the driver to be identified.

At a step 202, the DMS verifies that the driver's environment is in a given reference state. The given reference state corresponds to the reference vehicle data. Thus, the DMS 110 compares current vehicle data with the reference vehicle data, stored locally or in the first server 120, in order to verify that the driver's environment is in the reference state.

Current vehicle data can be acquired by the GPS module 116, by the camera 112, from the operating status of the on-board devices 113 and 114 and/or from the sensor(s) 111.

In the case where the current vehicle data corresponds to the reference vehicle data, the method proceeds to step 203 described below.

The fact that the compared data correspond may indicate that an absolute value of their difference is less than a given threshold, predetermined for example. For example, when one of the reference vehicle data is a reference cabin temperature of 25°C, it is considered that the current temperature is close to the reference temperature if the temperature is between 24 and 26°C, i.e. a threshold set at 1°C for the comparison. Similarly, when one of the reference vehicle data is a given first brightness level, and the current vehicle data is a second brightness level, the two levels are close if the absolute value of their difference is less than one given threshold. The reference vehicle data can also be intervals, in which case the match is effective when the current data is included in the reference interval. The interval can for example be a time slot. In this case, the current vehicle data is a current timetable, and it corresponds to the reference vehicle data, if the current timetable is included in the time slot.

In the case where the current vehicle data is different from the reference vehicle data, the method comprises a step 204 of modifying the current vehicle data.

The modification step 204 may include:

- the display on the HMI 119 of a message intended for the driver telling him to modify one or more of the current vehicle data. For example, the message can tell the driver to modify the brightness, for example by lowering a sun visor or moving the vehicle into the shade, or, when the noise level is too high, to move the vehicle to a less noisy area. or to close the windows of the vehicle 100;

- automatic modification, without driver intervention, of current vehicle data. Such automatic modification may include modifying the state of the vehicle's ventilation and heating system so as to change the current cabin temperature. The automatic modification may also include switching off the car radio.

At a step 203, the vehicle 100 is in a reference state, and the DMS 110 collects current physiological data from the driver. As stated previously, common physiological data can be derived from:

- of the camera 112;

- the physiological sensor(s) 111;

- user devices 130 and 131;

- other sensors of the vehicle 100 or external to the vehicle 100.

At an optional step 205, the DMS 110 can receive a self-declaration from the driver identified in step 201, in particular via the HMI 119. Such a self-declaration identifies the state of fatigue of the driver, perceived by the driver himself. -even.

Alternatively, optional step 205 can be performed before step 203 presented above.

In a step 206, the DMS 110 determines whether the driver's state of fatigue is acceptable or not, based on the current physiological data collected in step 203. Optionally, the determination in step 206 can further take into account of the self-declaration received at step 105.

In order to determine whether the state of fatigue of the driver is acceptable or not, the current physiological data is compared with the reference physiological data stored locally or on the second remote server 121.

If the current physiological data are identical or close to the reference physiological data, the driver can be considered able to perform a driving task and the method goes to a step 207.

Otherwise, if the current physiological data is different, or significantly different, from the reference physiological data, the driver can be considered tired and the method goes to a step 209.

Thus, the data are considered close if they are not significantly different. “Significantly different” can mean for example that the absolute value of a difference between a reference user datum and a current user datum is less than a given threshold, for example predetermined.

If the driver is considered fit, or not very tired, a program or a route can be indicated, via a screen of the vehicle 100 for example, at step 207. The program can for example correspond to the program of a working day , in particular in the case where the driver is a professional driver.

At a step 208, the DMS 110 can authorize the starting of the vehicle 100 by the driver.

If the driver is considered tired, the DMS 110 can determine if the program for the day or if the route can be adapted to the state of fatigue, at step 209.

In the event that the program or the route cannot be adapted, for example because the current physiological data is too far from the reference physiological data, the DMS 110 can prevent the vehicle from starting. In addition or as a variant, an alert message can be displayed on the HMI 119 to indicate to the driver that he is too tired to drive. As a variant or in addition, an alert message is transmitted to the second server 121 storing the user's personal data, or to another remote server.

In the event that the DMS 110 determines that the route or program for the day can be adapted, the DMS 110 adapts the driving route or the program for the day at a step 211, for example by providing additional breaks or by reducing the total travel time. No restriction is attached to the adaptation of the route or the program of the day.

The DMS 110 then authorizes the starting of the vehicle 100 by the driver.

Step 209 is optional and step 210 can be performed by default when the driver is tired. Alternatively, step 209 is optional and steps 211 and 212 are performed by default when the driver is tired.

There presents the structure of a driver control device 110, such as the DMS 110 presented above, according to one embodiment of the invention.

The DMS 110 can comprise a processor 302 and a memory 301, the processor 302 being able to implement the steps of the method illustrated with reference to the , for example by executing instructions stored in the memory 301. The memory 301 can further comprise the reference vehicle data and/or the reference physiological data, as explained previously. In addition, the memory may store the identifier of vehicle 100 and other characteristic data of vehicle 100.

The device 110 can comprise a first interface 303 able to communicate with the GPS module 110.

The device 110 can comprise a second interface 304 capable of communicating with the physiological sensor(s) 111.

Device 110 may include a third interface 305 able to communicate with camera 112.

The device 110 can include a fourth interface 306 capable of communicating with the first on-board device 113.

The device 110 can include a fifth interface 307 capable of communicating with the second on-board device 114.

Vehicle 100 may include more than two on-board devices, and to this end, device 110 may include additional interfaces for communicating with these additional on-board devices.

The device 110 can comprise a sixth interface 308 able to communicate with the memory 115 of the vehicle 100.

The device 110 can further comprise a seventh interface 309 able to communicate with the first external communication interface 117.

The device 110 can further comprise an eighth interface 310 able to communicate with the second external communication interface 118.

The device 110 can further comprise a ninth interface 311 able to communicate with the HMI 119.

No restriction is attached to the interfaces introduced above, which can be wired, data bus or wireless.

Some of the above interfaces can be shared. No restriction is attached to the number of interfaces of device 110.

The device 110 can further comprise an internal clock 312. Alternatively, the device 110 is connected to a clock of the vehicle 100 which is external to it.

The present invention is not limited to the embodiments described above by way of examples; it extends to other variants.

Claims (10)

Method for checking the state of fatigue of a driver of a vehicle (100) comprising the following steps, prior to starting the vehicle:
- storage (200) of reference physiological data in a memory;
- checking (202) that a driver's environment is in a given reference state;
- when the driver's environment is in the given reference state, obtaining (203) current physiological data of the driver;
- comparison (206) of the current physiological data with the reference physiological data;
- Determination (206) of a state of driver fatigue based on said comparison . A method according to claim 1, wherein when the driver's environment is not in the given reference state, the method further comprises:
- the display (204) of a message intended for the driver indicating to modify one or more current vehicle data representative of the driver's environment; Or
- the automatic modification (204) of current vehicle data representative of the driver's environment. Method according to claim 1 or 2, further comprising a step of controlling (208; 210; 212) the starting of the vehicle (100) according to the determined state of fatigue. Method according to claim 1 to 3, in which, comprising a step of adapting (211) a route or a driving program to the state of fatigue of the driver. Method according to one of the preceding claims, in which the physiological data of the driver are stored in association with a user identifier, and comprising, prior to the verification (202) of the driver's environment, a step of identifying (201) of the driver. Method according to one of the preceding claims, in which the step of verifying (202) that the driver's environment is in a reference state comprises comparing (202) current vehicle data with reference vehicle data. A method according to claim 6, wherein the reference vehicle data comprises at least one of the following:
- a vehicle reference speed;
- reference lighting of a cabin of the vehicle;
- reference settings for a heating and ventilation system;
- reference infotainment settings;
- one or more reference location zones of the vehicle; and or
- a reference moment or a reference time slot. Method according to one of the preceding claims, in which the reference physiological data comprises at least one of the following elements:
- a reference weight;
- a reference blood pressure;
- a reference heart rate; and or
- reference electroencephalogram measurements. Computer program comprising instructions for implementing the method according to any one of the preceding claims, when these instructions are executed by a processor (302). Device for controlling a driver (110) of a vehicle comprising:
- a memory (301) for storing reference physiological data or an interface for accessing a memory (115; 121) for storing physiological data;
- a processor (302) configured for:
verifying that a driver's environment is in a given reference state;
when the driver's environment is in the given reference state, obtaining current physiological data of the driver;
comparing current physiological data with the reference physiological data;
determining a fatigue state of the driver based on said comparison.