ES2212888B1 - SYSTEM AND DEVICE FOR THE PREDICTION IN THE TIME OF THE DEGREE OF CARE OF A DRIVER. - Google Patents

Abstract

System and device for predicting the degree of attention of a driver over time. The system is intended to predict the degree of attention that the driver of a vehicle has at all times, as well as calculate the time left for the driver's attention to reach worrying levels, acting prior to that predictable state, for which an electronic control unit (1), an active signal generator (2), a direction turn sensor (6), active signal emitters (16), response sensors (7) of the conductor are provided , as well as a calibration subsystem and optionally peripheral subsystems that allow to activate an emergency signal (8), a horn (9), the brakes (10), the fuel injection system (11) and the steering (12), in order that in the event that the driver does not perceive signals originated by the system in the presence of a lack of attention in driving, the vehicle's speed can be reduced, a steering wheel vibration can occur, etc. That is to say, the system allows to calculate the tendency that the driver has towards a lack of attention in the driving, and therefore to calculate the time that it takes for the attention of the driver to arrive at worryingly low levels.

Description

System and device for prediction in the time of the degree of attention of a driver.

Object of the invention

The present invention relates to a system intended to know the degree of attention that the driver of a vehicle owns at all times, as well as calculating the trend of it and, therefore, to predict the time left before Driver's attention reaches worryingly low levels. The system is based on combining the signals obtained in the identification of angular wheel movements vehicle guidelines and signals obtained through the periodic actuation by the driver of actuators in response to emitted light and / or acoustic signals randomly by a control unit. That is, it is about predict what will happen to the driver and take action Timely to avoid it.

It is an intelligent and expert system with own capacity of management and decision, and based on it with ability to act on different components of the vehicle.

The system can also serve as a "box black "as soon as it has the ability to file incidents occurred during a trip or tour.

Therefore, the invention allows to know in every moment the degree of attention that the driver of a vehicle is lending to driving, memorize it for a whole route, study its evolution, calculate its tendency, determine the time left for the driver to reach a level insufficient attention to driving and, before that happen, notify the driver of the risk.

The system can be complemented with subsystems peripherals that handle some of the essential elements of the vehicle, such as brakes, fuel injection, steering, speakers, lights, etc., also including a subsystem of initial calibration by verifying the status of driver concentration at the time the trip begins.

Background of the invention

It is demonstrated by the statistics that they produce numerous accidents due to a lack of attention of drivers, well caused by fatigue, drowsiness or Other causes Some studies estimate the number of accidents with an undetermined cause and therefore they blame distractions, fatigue or drowsiness.

Regarding fatigue or lack of attention, two evidences are known, since fatigue leads always a difficulty to keep the line straight as well as the difficulty in appreciating the visual stimuli that arrive through the indirect field of vision.

As is known, when a driver goes concentrated continuously perceives visual stimuli, some in the direct field of vision and others in the indirect, such as the appearance in the distance of another vehicle, some children in a garden side, another vehicle that is perceived in the rearview mirror and that appreciate that it comes at great speed, etc.

The perception of these stimuli entails immediately voluntary viewing by the driver, the which discriminates if you have to do something or if you have to do it in the future. Well, when the fatigue in the driver increases the "residual" attention is increasingly focused on the road ahead and stop serving your field of vision indirect, with the risks that this entails, since the loss of information that arrives through this indirect field of vision implies ignorance of a part of the environment, and security implies a total knowledge of the circumstances that concur in the circulation.

Systems that are based on measuring the driver's vital signs to determine the drowsiness of the driver are known, either by measuring the heart rate, either by measuring the pressure of the hands on the steering wheel, or by measuring the flicker frequency, etc., although It is true that the systems hitherto experienced are not fully reliable, since they may be influenced by other factors, such as driver's corpulence, age, sex,
etc.

There is no known system that is trained to predict the degree of attention a driver will have in a certain time, so the existing systems in the currently allow a critical attention situation to reach occur

Description of the invention

The system that is recommended is not provided precisely to detect a degree of driver attention by below a pre-established minimum, but is intended for predict the degree of attention that the driver will have in the future, as well as to calculate the time left for the Driver's attention reaches worrying levels, acting with prior to that possible state.

More specifically, the system is based on combining Two types of measurement: on the one hand get a direction signal of the vehicle, corresponding to the lack of precision in the trajectory maintenance, and on the other hand get the degree of driver attention at any time by actuation newspaper that this one must realize on some actuators, in response to active luminous and / or acoustic signals generated randomly by an electronic control unit.

The system is also complemented by a initial calibration subsystem that allows to verify the status of driver concentration at the time of starting the trip, being able to complement itself with peripheral subsystems of action on elements of the vehicle, such as on the brakes, on the steering, on the lights, on the horn, etc.

The system for the development of its functions It basically comprises the following:

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A electronic control unit

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A active signal generator.

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A steering turn sensor.

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Some active signal emitters.

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Some driver response sensors.

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A calibration subsystem

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Some peripheral control subsystems to vehicle elements, such such as brakes, injection, steering, speakers and lights.

Based on these means and their association functional, in case the driver does not react conveniently, the system in question can effect the following functions:

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Activate a signal from emergency.

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Activate a sound signal inside vehicle.

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Automatically and gradually reduce the vehicle speed

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Do that the advance of the vehicle is to pulls.

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Do Vibrate the direction of the vehicle.

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It could, under certain circumstances, control the direction of the vehicle to prevent the exit of the highway.

All in order to warn the risk driver, as well as other drivers or users of the highway.

That is, the system according to the invention controls automatically and constantly if the driver has difficulties in:

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Keep track rectilinear

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Attend to visual stimuli located out of direct field of vision.

Given these circumstances or factors the system in its operability acts in a way that:

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Follow the real trajectory and compare it with the desired theoretical one.

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Known the degree of attention of the driver according to the signals that They appear in the field of vision.

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Calculate the maintenance trend of the trajectory.

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Calculate the trend of the evolution of degree of attention of the driver.

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Compare the evolution of referrals trends.

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Verify the compatibility of these trends.

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Calculate estimated time for the driver's attention level reaches a threshold of risk.

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Warn to the driver.

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Control the technological functions of the own vehicle

As is evident, the advantages and benefits social that are obtained through the application of the system are numerous, citing as most important:

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Be Avoid a lot of accidents.

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Be eliminates the personal cost of care in accident victims, with the consequent economic savings.

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Be improves the quality of work of the driver.

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Be you will get a decrease in the cost of insurance premiums, etc.

Description of the drawings

To complement the description that is being performing and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical realization of it, is accompanied as part member of said description, a set of figures where with an illustrative and non-limiting nature, what has been represented next:

- Figure 1: consists of a representation Schematic of the device for predicting the degree of attention of the driver object of this invention.

- Figure 2: consists of four graphs representative of the determination of trends and time critic Tc, where graph (a) illustrates the determination of the trend of maintaining the vehicle's trajectory, the Graph (b) illustrates the determination of the trend of the degree of attention, graph (c) illustrates the compatibility or relationship between both trends, and graph (d) illustrates the determination of critical time Tc missing for the driver to reach a grade of minimum attention.

- Figure 3: consists of a flow chart representative of the operational sequence carried out by the system object of the invention, where with labels consisting of a letter within a circle indicates the different breaks or links in the diagram.

- Figure 4: consists of a continuation of the flow chart of figure 3.

- Figure 5: consists of a continuation of the flow chart of figures 3 and 4.

Preferred Embodiment of the Invention

Based on the referred figure, it can be observed as the system of the invention basically comprises a unit control electronics (1), which is provided with a base of times allowing to calculate the frequency and amplitude of the lateral movement of the vehicle, said unit being associated control electronics (1) to an active signal generator (2), and connected to a display (3) where a certain one will appear information. To such electronic control unit (1) are connected infrared sensors (4), sensors optical (5), a sensor for the rotation of the direction of the vehicle (6) and a series of response sensors (7).

In addition, that control unit (1), according to the signals received, is complemented by a series of subsystems control peripherals intended to control or interfere with any of the vehicle's own devices such as: the horn (9) of the vehicle, the brakes (10), the injection system of fuel (11) thereof and the direction (12), a signal of emergency (8), and can also send signals to activate a yellow or caution light (13), a red or hazard light (14) and an interior horn (15).

Through the active signal generator (2) stimulus emitters can be activated (16).

According to the block diagram of the figure 1, the operation according to a preferred embodiment of the System object of the invention is as follows:

1º.- From the beginning of the vehicle journey, the steering rotation sensor (6) of the vehicle, sends signals to the electronic control unit (1), signals that indicate the angle of rotation of the direction on the neutral point, that is on the straight line. The sensor cell of the rotation of the address (6) may be any type of sensor known in the state of the art, and for example measure the steering wheel rotation of the vehicle through a differential magnetic pickup system or simply a rheostat., transforming the measurement of the turn into a proportional signal for example in millivolts.

2º.- Because what matters is the straight line movement with wide curves, the electronic unit control (1) is temporarily deactivated once it detects that the vehicle is taking a medium or small radius curve, reactivating again when the vehicle circulates again in the conditions referred to above.

3º.- The system records and archives in its memory, from the beginning of the tour, both the amplitudes and the frequencies of alternative vehicle movements around of the path required by the driver, either straight or turning large.

In this way a record of the driver behavior along the entire route, all incidents being registered in the system occurred

4th.- The system continuously compares the signals received from the steering rotation sensor (6), looking for some mathematical relationship that allows establishing a trend with respect to time base, that is, compare continuously said signals to determine if their frequency is stable, increasing or decreasing, so that in the case that the tendency found is decreasing, it means that the amplitude of the zigzag that describes the vehicle is growing, data that is considered by the system as a sign of possible increase in driver fatigue and decreased attention in the driving.

5th.- Simultaneously, and depending on the trends detected by the electronic control unit (1) based on the data received from the pickup cell of the vehicle address (6), the system is generating about stimuli or randomly active signals, through the active signal generator (2), signals that are sent to the emitters (16) in order for the driver to respond to them through the response sensors (7).

6 .- Said stimulus emitters (16) present the signals in the driver's indirect field of vision, is say, rearview mirrors and front windows lateral. Other signals can also be generated in others vehicle points located in the indirect field of vision of the driver, such as dashboard and windshield corners. These signals are purely optical in a first phase, although the driver will take more than a certain time in advance in activate the corresponding response sensor (7), the signal optics is complemented by a sound warning generated likewise by the electronic control unit (1).

7º.- The driver, when perceiving these signals active should trigger the commented response sensors (7), which are in turn connected to the electronic control unit (1), then calculating the control unit (1) the time of driver reaction. These sensors (7) may consist of simple push buttons strategically located near the hands of the driver, or these sensors (7) can be about acoustic sensors sensitive to the driver's voice, or any other type of sensor that is considered appropriate.

8 ° .- The reaction times of the driver are registered and filed in the memory of the unit itself control electronics (1).

9 .- The system also compares and in a way Continue the reaction times of the driver, looking for some mathematical relationship that allows establishing a trend with respect to the basis of times, stable, increasing relationship times or decreasing, so that in the event that the trend found to be increasing, the system considers that data as a sign of possible increase in driver fatigue and decrease in driving attention.

10º.- That tendency allows to establish the time missing until the driver reaches a minimum level of Attention. This minimum level of attention has been determined by statistical form from experimental data, and from that trend starts a sequence of performances and warnings, which are the following:

to)

twenty minutes before that minimum time, it lights up so flashing a yellow light or signal (13) located on the dashboard controls, while the system continues operationally from way that will verify if the trend found above, that served as the basis for the calculation, is maintained, increases or decreases, of so that in any case the system keeps calculating the time missing for the driver to reach the minimum level of Attention.

b)

If he time mentioned above increases since the appearance of the signal up to a certain minimum, the system turns off the light corresponding to the yellow signal (13).

C)

If he time continues to decrease, with an advance of for example 15 minutes, the system replaces the yellow signal (13) with a signal or red light (14), also flashing, following the system continuously checking the trend evolution, calculating time.

d)

In a Estimated time of 10 minutes, a beep or horn indoor (15) is activated in addition to the corresponding light signal in the red light (14). In the event that the driver does not perceive those signals that establish a minimum level of attention for that one, then the system begins to influence a series of devices or own subsystems of the vehicle, activating, for example, the brake system (10), regardless of driver, activation which is done intermittently which makes the advance of the  vehicle is made on a non-regular basis, that is, pulling. An emergency signal from the vehicle is also turned on and it acts on the fuel injection system (11), looking reduced vehicle speed to a fixed value that can Estimate between 40 and 60 km / hour.

Also, the system sends a signal to the pump management assistance (12), acting on it and making it oscillate and consequently the steering wheel regarding its central point.

The system would also act on the horn (9) of the vehicle, intermittently and can even lower the speed up to 20 km / hour.

Obviously, the speeds and times referred so far have been cited by way of example, the system can be calibrated to act in other times and / or speeds.

In certain circumstances the system could completely control the direction of the vehicle, although for this peripheral subsystems based on any of the techniques known in the state of the art, which in in combination with the electronic control unit (1), they will detect the road profile, and between whose peripheral subsystems an optical system that detects the lateral illumination can be mentioned of the vehicle with respect to the white lines painted on the asphalt, and on the other hand an ultrasonic sensor located vertically in the front corners of the vehicle, to measure vertical distance to the asphalt.

On the other hand and as already said with previously, the system can be complemented with a subsystem of calibration, based on which and before starting the tour the driver must enter his personal identification in the system, starting the driver calibration sequence, presenting the system on the display (3) the procedure that the driver must follow.

The calibration subsystem consists of set the initial level of the driver based on his response time for a series of random signals sent by the system, so that that initial level marks on the one hand the degree of initial concentration of the driver, and serves as the basis for subsequent calculations, and on the other hand allows you to choose the minimum level of attention between different databases available in the system.

The following describes as an example the operating sequence carried out by the system:

Phase TO

Data collection and archiving

1.- Start of the application: When putting the contact Calibration starts from the vehicle.

2.- Calibration: It is carried out through the sending a series of active signals and calculating the time of driver reaction. The calibration has two results, positive and negative.

2.1.- Negative result, in the case in which driver is not able to maintain a minimum degree of attention and essential for driving: The contact is cut off and returned to "1".

2.2.- Positive: The vehicle can start occur

3.- Continuous measurement of the speed of the vehicle (Vv): the speed can be higher or lower than 50 Km / hour

3.1.- If the speed is lower the system is waiting.

3.2.- If the speed is higher the system continuously controls the steering wheel's angle of rotation.

4.- Max steering wheel angle: The angle maximum acceptable rotation (?) is the maximum acceptable for the operation of the system and with which areas of driving with very sharp bends or city driving. This determined for each vehicle based on the distance between axes and direction geometry.

4.1.- If the steering wheel angle (? 1) is greater than (?) for a time greater than (T1) (experimentally determined) the system returns to 3.2.

4.2.- If (α1) is less than (α) the system goes on to determine the trend in the direction.

5.- Determination of the trend of vehicle path maintenance: The system measures continuously the maximum points in angular displacements of the steering wheel. The system eliminates the singular points produced for a performance that goes beyond the general tone of the measures, as for example it can be a blow of the wheel to save a obstacle. The system calculates the average slope using a conventional mathematical procedure. The system stores in the Memory the slope.

6.- Current slope: The current slope (Pa) is defined as the slope found in the last sequence of time (t). This pending is filed in the system memory and It is continuously compared with the five current slopes previous. In other preferred embodiments, this comparison is can perform with a greater or lesser number of previous slopes and that is considered optimal to determine this trend.

6.1.- If "Pa" is lower than the slopes previous the system returns to "2.2", since this situation indicates that the trend in the direction is not maintained vehicle.

6.2.- If "Pa" is higher than the slopes The trend that gives rise to an indication that the driver is losing attention, and then the system sends a series of active signals through the signal generator (2) and of the signal emitters (16).

7.- Sending active signals: The system will send a series of 4 signals (a higher value or less than 4).

8.- Measurement of the response time of the driver: It is determined by the time it takes for the driver to each signal to perform a response action on the sensor (7) adequate; This time is recorded by the system.

8.1.- If the driver does not respond before three seconds the system emits an audible warning that ceases when produces the driver's response and returns to "8".

8.2.- The driver's response generates the measurement of response time and its file in memory and it Increase an I.S.A. active signal counter = I.S.A. + 1.

9.- ¿I.S.A. > 4?

9.1.- Negative response: the system returns to "7".

9.2.- Positive response: the system eliminates singular points and calculates the average of the 4 reaction times (Tm), and file the result.

10.- Default sending of active signals: every 10 minutes (can be adapted to another value) the system performs the sequence of points "7, 8 and 9", and determines the time reaction (Tm).

Phase B

Critical Times Prediction

11.- With every 4 consecutive points corresponding to singular determinations of the time of reaction (Tm), the system calculates the average slope (Pm) corresponding to those points, and thus determines the tendency of the degree of attention of the driver.

12.- That slope will cut into some axes of coordinates, in which the ordinates correspond to the time of trip and abscissa correspond to the reaction time, to the horizontal line representing the level corresponding to a degree of dangerously low attention, which has been determined experimentally. The cut-off point between the two, when projected to ordinate axis will give us the travel time (Tc) that is missing (from keep the current trend) until the driver reaches that Dangerously low level of attention.

12.1.- If that Tc is greater than 90 minutes the system returns to point 3.

12.2.- Yes 90 min. > Tc> 20 min. the system Compare the result with the three times (Tc) above.

12.2.1.- If the previous times are some increasing and other decreasing, the system decreases the sequence of sending active signals at 8 min. interval, and return to point 3.

12.2.2.- If the previous times are all decreasing, the system decreases the signal sending sequence active at 5 min. interval, and return to point 3.

12.3.- If Tc <20 min., The system turns on the dashboard a warning signal consisting of a light flashing yellow and returns to point 3.

12.4.- If Tc <15 min., The system turns on a flashing red light and return to point 3.

12.5.- If Tc <10 min., The system, keeping the red light, it activates an audible signal intermittently inside and return to point 3.

12.6.- If Tc <5 min., The system activates a intermittent braking while maintaining the red light and the audible signal.

12.7.- At Tc = 0, the system turns on the signal of emergency and cut the fuel injection until the Vehicle speed (Vv) go down to 50 Km / hour.

12.7.1.- If Vv> 50, the system returns to 12.7

12.7.2.- If Vv <50, the system opens the fuel injection until Vv> 50 and the system returns to 12.7

12.8.- 5 min. later than time Tc = 0, the system, maintaining the speed of 50 km / hour, the signals of emergency, the red light and the intermittent sound signal, sends a signal to the steering system so that the steering wheel starts to vibrate.

13.- From this moment, and in a way optional, the system would activate optical sensors and ultrasounds that detect the white stripes that delimit each lane of a way, so that, in conjunction and connection with the control unit and management system, be sent to the latter the information necessary to keep the vehicle within road limits.

Claims (13)

1. System for the prediction in time of the degree of attention of a driver, whose purpose is to know at all times the degree of attention of the driver of a vehicle and determine the time left for the degree of attention to reach a critical value , characterized in that it consists of: continually determine the trend in the vehicle path maintenance, based on the measurement of the maximum points of the angular displacements of the vehicle steering wheel, continually determine the trend of the degree of driver attention, when the trend in maintenance of the vehicle's trajectory offers signs of a loss criticism of the degree of attention of the driver, obtaining said trend of the degree of attention based on the measurement of the times of driver reaction to stimuli randomly caused by the system, calculate the critical time left for the Driver's attention level reaches a risk value predetermined, take preventive measures by activating means of warning or alarm when the calculated critical time is below of a predetermined time. 2. System for the prediction in time of the degree of attention of a driver, according to claim la, characterized in that for the determination of the trend in the maintenance of the trajectory of the vehicle, the system continuously measures the maximum points in angular displacements of the steering wheel, and calculates the average slope from these points. 3. System for the prediction in time of the degree of attention of a driver, according to claim 1, characterized in that to determine whether the trend in the maintenance of the vehicle's trajectory offers indications of a loss of attention of the driver, the system compares continuously the current slope (Pa) with several consecutive slopes obtained prior to said current slope (Pa). 4. System for the prediction in time of the degree of attention of a driver, according to claim 1, characterized in that the determination of the trend of the degree of attention of the driver is performed by calculating average slope from various singular measurements of the reaction time from the driver to various stimuli caused by the system. 5. System for the prediction in time of the degree of attention of a driver, according to claim l, characterized in that for the calculation of the critical time (Tc) the average slope corresponding to the trend of the degree of attention is transferred, it is transferred to coordinate axes in which the ordinate axis is the travel time, the abscissa axis is the reaction time of the driver, and where a horizontal line corresponding to a critical attention level of the driver has been established, obtaining the critical time (Tc) by intersecting said slope with said horizontal line. 6. System for predicting the degree of attention of a driver in time, according to claim 1, characterized in that it is capable of acting on any of the vehicle's own devices, such as the steering, the brake system, the system of injection, from a critical time value. 7. System for predicting the degree of attention of a driver in time, according to previous claims, characterized in that the stimuli caused by the system consist of optical stimuli produced in the driver's indirect field of vision, and / or acoustic stimuli produced inside the vehicle. 8. System for the prediction in time of the degree of attention of a driver, according to claim 7, characterized in that the optical stimuli are caused from the rearview mirrors of the vehicle or from the front and side windows. 9. System for the prediction in time of the degree of attention of a driver, according to previous claims, characterized in that it establishes a minimum vehicle speed and a maximum steering angle of rotation, outside of which the system enters a waiting state in which it is not operational. 10. System for predicting the degree of attention of a driver in time, according to previous claims, characterized in that it has a calibration subsystem to determine the degree of initial attention of the driver before starting the driving of the vehicle, which is based in measuring the reaction time of the driver to stimuli randomly caused by the system. 11. Device for the prediction in time of the degree of attention of a conductor, to carry out the system described in claims 1 to 10, characterized in that it has: an electronic control unit (1) that implements a time base based on which it is possible calculate the frequency and amplitude of lateral movement of the vehicle, a sensor cell (6) of the steering turn of the vehicle that sends the measured signals to the electronic unit control (1), an active signal generating unit (2) governed by the electronic control unit (1), by means of which stimulus emitters are activated (16), a plurality of response sensors (7) intended to be operated by the driver in response to stimuli caused by stimulus emitters (16), and whose activation is collected by the electronic control unit (1), Y a plurality of alarm emitters (13), (14) and (15) controlled by the electronic control unit (1). 12. Device for the prediction in time of the degree of attention of a conductor, according to claim 11, characterized in that it has peripheral control subsystems controlled by the electronic control unit (1), and through which said control unit Control (1) is capable of interfering with the vehicle's injection system, in the direction, in the horn, in the vehicle's braking system and activating an emergency signal. 13. Device for the prediction in time of the degree of attention of a driver, according to claim 11, characterized in that the electronic control unit (1) stores all the data obtained by the cell (6) capturing the steering turn of the vehicle, and the data related to the driver's reaction times on the response sensors (7) obtained during the entire vehicle journey.