JP2012000280A - Brain wave estimating device, brain wave estimation method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brain wave estimating device which estimates a neck myoelectric potential without adhering an electrode to a neck, and removes the estimated neck myoelectric potential from the electroencephalographic data as a noise component, and to provide a brain wave estimation method and a program.SOLUTION: The brain wave estimating device 100 includes: an engine operation determination section 110; a brain wave measurement section 120 for measuring a brain wave; a face direction measurement section 130 for measuring an angle of the face direction of a driver; a neck myoelectric potential data accumulation section 140 for associating the measured face direction angle and the electroencephalographic data measured by the brain wave measurement section 120 to accumulate as a neck myoelectric potential data; a neck myoelectric potential estimation section 150 for estimating the neck myoelectric potential according to the measured face direction angle, referring to the neck myoelectric potential data accumulated in the neck myoelectric potential accumulation section 140; and a brain wave signal processing section 160 for removing the neck myoelectric potential from the measured electroencephalographic data as the noise component. Thus, the neck myoelectric potential component that is directly influenced by the driving action while driving is removed from the electroencephalographic data without directly measuring the neck myoelectric potential.

Description

  The present invention relates to an electroencephalogram estimation apparatus, an electroencephalogram estimation method, and a program, and more specifically, in an electroencephalogram measurement during driving of a vehicle, an electroencephalogram estimation during driving that removes a signal component of cervical myoelectric potential accompanying driving behavior from electroencephalogram data. The present invention relates to an apparatus and an electroencephalogram estimation method.

  Patent Document 1 describes a brain motor function analysis / diagnosis method and apparatus that extracts a brain potential signal component that changes in relation to exercise from brain wave data and performs an analysis diagnosis of the brain motor function. The brain motor function analysis and diagnosis method described in Patent Document 1 focuses on the fact that brain potential changes that change in relation to exercise are easily detected as changes in frequency, and the motor-related brain potentials embedded in the electroencephalogram data. A minute signal component can be easily measured in the form of time change of frequency distribution by wavelet transform.

  FIG. 1 is a diagram showing a brain motor function analysis and diagnosis method described in Patent Document 1. In FIG.

  As shown in FIG. 1, digital data of brain potential acquired from the human scalp as a subject, digital data of eyeball potential, digital data of earlobe potential, and digital data of myoelectric potential acquired from the skin are time data. It is once stored in the file storage device 21 together with the marker.

  The addition average processing unit 22 reads a plurality of waveforms of the brain potential digital data from the file storage device 21 and performs an addition average process. The addition-averaged brain potential digital data is subjected to wavelet transform in the wavelet transform processing unit 23.

  The dynamic spectrum generation processing unit 24 generates a dynamic spectrum from the wavelet transform result and stores it in the file storage device 25.

  On the other hand, the eyeball potential digital data, earlobe potential digital data, and myoelectric potential digital data acquired from the skin simultaneously with the brain potential are each wavelet transformed by the wavelet transform processing unit 26.

  The dynamic spectrum generation processing unit 27 generates a dynamic spectrum from each wavelet transform result and stores it in the file storage device 25.

  The change occurrence time detection processing unit 28 detects the simultaneous change of the wideband frequency components on the dynamic spectrum because the change of the myoelectric potential caused by the start of the exercise is pulsed and includes the wideband frequency. The time position is detected and output as the reference time.

  The brain motor function analysis processing unit 29 analyzes the dynamic spectrum of the brain potential based on the reference time, and identifies the motion-related brain potential.

JP 2002-272692 A

Okakane et al. “Head Posture Estimation System Using Particle Filter with Adaptive Diffusion Control” IEICE Transactions D-II Vol. J88-D-II No. 8, 2005 (pp. 1601-01603)

  The electroencephalogram estimation apparatus described in Patent Document 1 is obtained by attaching a myoelectric potential measuring electrode directly to the neck in order to extract from the electroencephalogram data a signal component of electroencephalogram that changes in relation to exercise. The exercise start time is detected from the data. Most of the noise included in the measured electroencephalogram data is cervical myoelectric potential generated by moving the cervix, and accurately measuring this cervical myoelectric potential leads to improvement in measurement accuracy of the electroencephalogram data.

  However, since electroencephalogram measurement during driving is performed by attaching electrodes to the skin of the head, the myoelectric potential generated by moving the neck portion has a great influence on the electroencephalogram data measurement. That is, during driving, it is difficult to stably measure the electroencephalogram due to safety confirmation actions such as visual confirmation that moved the neck, and because the driver frequently performs safety confirmation actions, electrodes are attached to the neck. Therefore, it was difficult to measure.

  An object of the present invention is to provide an electroencephalogram estimation apparatus, an electroencephalogram estimation method, and a program for estimating a cervical myoelectric potential without attaching an electrode to the cervix and removing the estimated cervical myoelectric potential from the electroencephalogram data as a noise component It is to be.

  An electroencephalogram estimation apparatus according to the present invention estimates a cervical myoelectric potential in accordance with an electroencephalogram measurement unit that measures an electroencephalogram, a face orientation measurement unit that measures a face orientation angle, and a face orientation angle measured by the face orientation measurement unit. A configuration is provided that includes a cervical myoelectric potential estimation unit and an electroencephalogram signal processing unit that removes the cervical myoelectric potential estimated by the cervical myoelectric potential estimation unit from the electroencephalogram data measured by the electroencephalogram measurement unit as a noise component.

  The method of estimating an electroencephalogram according to the present invention includes a step of measuring an electroencephalogram, a step of measuring a face orientation angle, a cervical myoelectric potential estimation step of estimating a cervical myoelectric potential according to the measured face orientation angle, Removing the cervical myoelectric potential estimated from the electroencephalogram data as a noise component.

  From another viewpoint, the present invention is a program for causing a computer to execute each step of the above-described electroencephalogram estimation method.

  According to the present invention, a cervical myoelectric potential can be estimated without attaching an electrode to the cervix, and the estimated cervical myoelectric potential can be removed from the electroencephalogram data as a noise component. Without directly measuring the cervical myoelectric potential, it is possible to measure the electroencephalogram during driving by removing the cervical myoelectric potential directly affected by driving behavior during driving from the electroencephalogram data.

Diagram showing conventional brain motor function analysis diagnostic method The block diagram which shows the structure of the electroencephalogram estimation apparatus which concerns on embodiment of this invention The figure which shows an example of a structure of the face direction measurement part of the electroencephalogram estimation apparatus which concerns on the said embodiment. The flowchart which shows the process of the electroencephalogram estimation method at the time of the driving | operation of the electroencephalogram estimation apparatus which concerns on the said embodiment. The figure which shows the data structure of the cervical myoelectric potential storage part of the electroencephalogram estimation apparatus which concerns on the said embodiment. The figure which shows the cervical myoelectric potential example of the cervical myoelectric potential storage part of the electroencephalogram estimation apparatus which concerns on the said embodiment. The figure which shows the example of an electroencephalogram frequency analysis when the driver | operator's face direction angle of the electroencephalogram estimation apparatus which concerns on the said embodiment is moved 30 degree | times to the right direction from the central axis of a head. The figure which shows the electrode position of the international 10-20 method The figure which shows the electroencephalogram frequency analysis result according to the driver | operator's face direction angle of the electroencephalogram estimation apparatus which concerns on the said embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment)
FIG. 2 is a block diagram showing the configuration of the electroencephalogram estimation apparatus according to one embodiment of the present invention. The present embodiment is an example applied to an electroencephalogram estimation apparatus that removes a signal component of cervical myoelectric potential associated with driving behavior from electroencephalogram data in electroencephalogram measurement during vehicle driving.

  2, the electroencephalogram estimation apparatus 100 includes an engine operation determination unit 110, an electroencephalogram measurement unit 120, a face orientation measurement unit 130, a cervical myoelectric potential storage unit 140, a cervical myoelectric potential estimation unit 150, and an electroencephalogram signal process. Part 160.

  The electroencephalogram estimation apparatus 100 removes a cervical myoelectric potential component that is directly influenced by driving behavior during driving from the electroencephalogram data without directly measuring the cervical myoelectric potential.

  The engine operation determination unit 110 determines whether or not the vehicle engine is started.

  The electroencephalogram measurement unit 120 measures an electroencephalogram.

  The face orientation measurement unit 130 measures the driver's face orientation angle. As a method for calculating the orientation of the driver's face, for example, there is a head posture calculation method based on image analysis using a particle filter with adaptive diffusion control described in Non-Patent Document 1. Details of the method of calculating the driver's face orientation will be described later with reference to FIG.

  The cervical myoelectric potential accumulation unit 140 associates the face orientation angle measured by the face orientation measurement unit 130 with the electroencephalogram data measured by the electroencephalogram measurement unit 130 and accumulates them as cervical myoelectric potential data.

  The cervical myoelectric potential estimation unit 150 associates the face orientation angle previously measured by the face orientation measurement unit 130 with the electroencephalogram data measured by the electroencephalogram measurement unit 120 and accumulates them in the cervical myoelectric potential accumulation unit 140, and the face orientation measurement unit The cervical myoelectric potential is estimated according to the face orientation angle measured at 130. Specifically, the cervical myoelectric potential estimation unit 150 associates the face angle and the electroencephalogram data measured by the face direction measurement unit 130 when the engine operation determination unit 110 determines that the engine of the vehicle is not started. When it is determined that the engine has been started, the cervical myoelectric potential is estimated according to the face orientation angle measured by the face orientation measuring unit 130.

  The electroencephalogram signal processing unit 160 removes the cervical myoelectric potential estimated by the cervical myoelectric potential estimation unit 150 from the electroencephalogram data measured by the electroencephalogram measurement unit 120 as a noise component. Specifically, the electroencephalogram signal processing section 160 is estimated by the cervical myoelectric potential estimation section 150 from the electroencephalogram data measured by the electroencephalogram measurement section 120 when the engine operation determination section 110 determines that the vehicle engine is started. Neck myoelectric potential is removed as a noise component.

  FIG. 3 is a diagram showing an example of the configuration of the face orientation measurement unit 130, and shows the configuration of a head posture calculation method using a particle filter with adaptive diffusion control.

  In this embodiment, the three-dimensional posture of the head is estimated based on input images from two cameras installed in front of the driver's seat.

  As shown in FIG. 3, the face orientation measurement unit 130 includes an initialization unit 131 that automatically acquires a three-dimensional model of the user's head, and a tracking unit 132 that tracks the head posture from the particle filter.

  The tracking unit 132 adaptively controls the diffusion of hypotheses in the head motion model of the particle filter. As the calculation of the driver's face orientation, the estimation accuracy when the user's head is stationary is maintained at a high level and the followability when the user suddenly moves is strong. Is suitable.

  In the head posture calculation method based on image analysis described in Non-Patent Document 1, the three-dimensional posture of the head can be estimated. In the cervical myoelectric potential estimation method according to the present embodiment, a change in the electroencephalogram output is observed according to the angle in the horizontal direction with respect to the central axis of the head. Calculate the angle.

  Further, instead of measuring the electroencephalogram data when the driver's face direction is moved laterally from the central axis of the head by an angle (0 ° to ± 40 °), the face direction measuring unit 130 is not limited to the rearview mirror side. A fixed target in the passenger compartment, such as the mirror position, is set in advance, and it is detected that the driver's face has moved in the direction of the target. The data may be stored in the storage unit 140.

  Hereinafter, the operation of the electroencephalogram estimation apparatus 100 configured as described above will be described.

  The electroencephalogram estimation apparatus 100 has different processing contents depending on the configuration before driving and during driving, and performs processing for storing the measured electroencephalogram data in association with the face direction angle of the driver before driving, and the face during driving. Neck myoelectric potential corresponding to the orientation angle is estimated, and processing for removing the neck myoelectric potential from the electroencephalogram data is performed. For this reason, in the present embodiment, engine operation determination unit 110 determines the state of the driver.

  FIG. 4 is a flowchart showing the process of the electroencephalogram estimation method when the electroencephalogram estimation apparatus 100 is in operation. In the figure, S indicates each step of the flow.

  In steps S1 to S4, a process of accumulating the electroencephalogram data measured in a quiet state before driving in association with the driver's face orientation angle is performed.

  In steps S11 to S15, a cervical myoelectric potential corresponding to the face orientation angle during driving is estimated, and a process of removing the cervical myoelectric potential from the electroencephalogram data is performed.

  First, the electroencephalogram data is measured when the driver before driving moves his / her face from the central axis of the head in the lateral direction by an angle (0 ° to ± 40 °) in a resting state. In order to measure the electroencephalogram data when the driver before starting the engine of the vehicle is in a resting state, the engine operation determining unit 110 determines whether or not the engine of the vehicle is started.

  When the engine operation determination unit 110 determines that the engine is not started, the face direction measurement unit 130 measures the face direction angle when the driver moves the face direction, and the electroencephalogram measurement unit 120 detects the brain wave. measure.

  Next, the cervical myoelectric potential estimation unit 150 associates the face orientation angle measured by the face orientation measurement unit 130 with the electroencephalogram data measured by the electroencephalogram measurement unit 120 and accumulates them in the cervical myoelectric potential accumulation unit 140. Focusing on the fact that the driver's face angle is correlated with cervical myoelectric potential, EEG data measured in a resting state before driving is correlated with the driver's face angle and stored as cervical myoelectric potential. . The above processing is repeated until the vehicle engine is started.

  Next, the electroencephalogram data of the driving driver is measured. The engine operation determination unit 110 determines whether or not the vehicle engine is started.

  When the engine operation determination unit 110 determines that the engine is started, the face direction measurement unit 130 measures the face direction angle when the driver moves the face direction, and the electroencephalogram measurement unit 120 detects the brain wave. measure.

  Next, the cervical myoelectric potential estimation unit 150 uses the cervical myoelectric potential accumulation unit 140 to estimate the cervical myoelectric potential from the face orientation angle measured by the face orientation measurement unit 130. The electroencephalogram signal processing unit 160 removes the cervical myoelectric potential estimated by the cervical myoelectric potential estimation unit 150 from the electroencephalogram data measured by the electroencephalogram measurement unit 120 and estimates the electroencephalogram data from which the cervical myoelectric potential during driving is removed. To do.

  Next, the engine operation determination unit 110 determines whether or not the vehicle engine has been stopped. If the engine operation determination unit 110 determines that the engine has ended, this processing flow ends.

[Processing when the driver is resting before driving]
Next, the processing flow of the electroencephalogram measurement method in a resting state before driving will be described in detail.

  First, in steps S1 to S4, a description will be given of a process of measuring brain wave data corresponding to the face orientation angle in a resting state before driving and accumulating it as cervical myoelectric potential during driving.

  In step S1, the engine operation determination unit 110 determines whether or not the vehicle engine is started. When the engine operation determination unit 110 determines that the engine has not been started, the process proceeds to step S2.

  In step S <b> 2, the face orientation measurement unit 130 calculates the face orientation of the driver at an angle in the lateral direction from the center axis of the head. The method of calculating the driver's face orientation has been described with reference to FIG.

  In step S3, the electroencephalogram measurement unit 120 measures an electroencephalogram with an electrode attached to the head. The measurement time is about 30 seconds, and the face direction is measured from the central axis of the head to the lateral direction at an angle of -40 degrees to 40 degrees in units of 10 degrees and is measured in a stationary state.

  In step S4, the cervical myoelectric potential estimation unit 150 performs Fourier transform (FFT) on the time-series brain wave data measured by the brain wave measurement unit 120, and extracts frequency components. This is used as a frequency component of the cervical myoelectric potential, and is stored in the cervical myoelectric potential accumulating unit 140 in association with the face orientation angle measured by the face orientation measuring unit 130.

  FIG. 5 is a diagram illustrating a data structure of the cervical myoelectric potential storage unit 140, and FIG. 6 is a diagram illustrating an example of cervical myoelectric potential of the cervical myoelectric potential storage unit 140.

  As shown in FIG. 5, the cervical myoelectric potential storage unit 140 includes data items of a face orientation angle, the number of data, a measurement time, a cervical myoelectric potential storage address, and a cervical myoelectric potential data number. Further, as shown in FIG. 6, the cervical myoelectric potential is composed of data items of frequency and power. The face orientation angle is stored in units of 10 degrees from -40 degrees to 40 degrees, and the frequency of the cervical myoelectric potential is stored in units of 0.1 Hz from 0.1 Hz to 45 Hz.

  For example, when the face orientation angle is set to 30 degrees in the face orientation measurement unit 130, the myoelectric potential estimation unit 150 performs Fourier transform (FFT) on the electroencephalogram data measured by the electroencephalogram measurement unit 120 to extract the frequency component of the electroencephalogram data. . The myoelectric potential estimation unit 150 stores the frequency component of the extracted electroencephalogram data in the cervical myoelectric potential of the cervical myoelectric potential storage unit 140 in units of 0.1 Hz from 0.1 Hz to 45 Hz, and the measurement time at the face orientation angle of 30 degrees. Then, the storage address of the cervical myoelectric potential and the number of cervical myoelectric potential data are stored, and the number of data is incremented by one.

  When the storage process of the cervical myoelectric potential storage unit 140 of the cervical myoelectric potential estimation unit 150 is completed in step S4, the process returns to step S1, and the processes from step S1 to step S4 are repeated before the engine is started.

[Processing of EEG estimation method during driving]
Next, the processing flow of the brain wave estimation method during driving will be described in detail.

  When the engine is started, the process proceeds to step S11.

  In the process of step S11, the same face orientation measurement process as in step S2 is performed, and in the process of step S12, the same electroencephalogram measurement process as in step S3 is performed.

  In step S <b> 13, the cervical myoelectric potential estimation unit 150 performs a process of extracting the frequency component of the electroencephalogram data measured by the electroencephalogram measurement unit 120 and a process of estimating the cervical myoelectric potential using the cervical myoelectric potential storage unit 140. Do.

  For example, when the face orientation measurement unit 130 measures a face orientation angle of 30 degrees, the cervical myoelectric potential estimation unit 150 performs Fourier transform (FFT) on the driving electroencephalogram data measured by the electroencephalogram measurement unit 120 and performs frequency components. To extract. The cervical myoelectric potential estimation unit 150 refers to the cervical myoelectric potential storage address and the number of data at the face orientation angle of 30 degrees of the cervical myoelectric potential storage unit 140, and determines the frequency and power of the cervical myoelectric potential as the number of data. Extract minutes. This is estimated as a cervical myoelectric potential at a face orientation angle of 30 degrees and passed to the electroencephalogram signal processing unit 160.

  In step S14, the electroencephalogram signal processing unit 160 performs a process of estimating electroencephalogram data from which the cervical myoelectric potential during driving is removed as a noise component.

  FIG. 7 is a diagram illustrating an electroencephalogram frequency analysis example when the driver's face angle is moved 30 degrees to the right from the central axis of the head.

  FIG. 7 is an example of electroencephalogram frequency analysis when the driver's face orientation angle is moved 30 degrees to the right. A method of removing cervical myoelectric potential from the electroencephalogram waveform during driving with reference to FIG. Will be described.

  The electroencephalogram signal processing unit 160 receives two components, the frequency component of the electroencephalogram data obtained by the cervical myoelectric potential estimation unit 150 and the cervical myoelectric potential. The neck myoelectric potential changes according to the driver's face orientation angle. For example, when the driver moves the face direction angle to the right by 30 degrees, the face direction measurement unit 130 detects that the driver's face direction angle is 30 degrees, and the cervical myoelectric potential estimation unit 150 Neck myoelectric potential data corresponding to a face orientation angle of 30 degrees is estimated as a neck myoelectric potential.

  The electroencephalogram signal processing unit 160 performs a process of removing cervical myoelectric potential from desired electroencephalogram data. For example, in the case where a β wave (13 to 20 Hz) is extracted as desired brain wave data to detect the driver's arousal state, the frequency component waveform (A) of the brain wave having a frequency in the range of 13 to 20 Hz in FIG. The cervical myoelectric potential estimation waveform (B) at a face angle of 30 degrees is used as an input waveform in the electroencephalogram signal processor 160, and the waveforms of (A)-(B) are analyzed as a β wave waveform at a face angle of 30 degrees. And the driver's arousal state is output.

  In step S15, the engine operation determination unit 110 determines whether or not the vehicle engine has been stopped. If the engine is not stopped, the process returns to step S11 and the processes from step S11 to step S14 are repeated. If the engine is stopped, this processing flow ends.

  In the processing flow described above, the case where the cervical myoelectric potential corresponding to the face orientation angle is accumulated in step S13 has been described, but the case where the cervical myoelectric potential corresponding to the face orientation angle is not accumulated will be described.

  FIG. 8 is a diagram showing electrode positions in the international 10-20 method. FIG. 9 is a diagram illustrating a result of analyzing the electroencephalogram frequency according to the driver's face orientation angle.

  The test subject wears an electroencephalograph (manufactured by TEAC, polymate AP-1132), uses an international 10-20 method (FIG. 8) for the electrode arrangement, the lead electrode is Oz (occipital region; intermediate between O1 and O2), reference electrode Is A2 (right earlobe) and the ground electrode is the forehead. The measurement of the electroencephalogram data is a result of measuring the potential of Oz with reference to the potential of A2, and measuring at a sampling frequency of 200 Hz and a time constant of 3 seconds.

  An electroencephalogram is composed of many components having various frequencies and waveforms. The most common classification of the electroencephalogram is a method of classifying the appearing waveform into a frequency band. Based on this method, it can be classified as δ wave (0.5 to 3 Hz), θ wave (4 to 8 Hz), α wave (8 to 13 Hz), and β wave (13 to 20 Hz). From the measurement result of FIG. 9, there is a change in the output (power) of the frequency component of the electroencephalogram according to the change in the lateral angle of the face.

  Thereby, even when the cervical myoelectric potential corresponding to the face orientation angle is not accumulated, the frequency component waveform of the electroencephalogram is 10 degrees or more and 30 degrees when the face orientation angle is less than 10 degrees (FIG. 9: pattern 1). If the angle is less than (FIG. 9: pattern 2), and if it is 30 degrees or more (FIG. 9: pattern 3), by defining a plurality of patterns according to the face orientation angle, for example, the face orientation angle is 35 degrees In this case, pattern 3 can be estimated as cervical myoelectric potential.

  As described above in detail, the electroencephalogram estimation apparatus 100 of the present exemplary embodiment includes an engine operation determination unit 110 that determines whether or not the vehicle engine is started, an electroencephalogram measurement unit 120 that measures an electroencephalogram, and driving. A face orientation measuring unit 130 that measures the face orientation angle of the person, and a cervical myoelectric potential storage unit 140 that associates the measured face orientation angle with the electroencephalogram data measured by the electroencephalogram measurement unit 120 and accumulates them as cervical myoelectric potential data. The cervical myoelectric potential data accumulated in the cervical myoelectric potential accumulating unit 140, the cervical myoelectric potential estimating unit 150 for estimating the cervical myoelectric potential according to the measured face orientation angle, and the measured electroencephalogram data An electroencephalogram signal processing unit 160 that removes the cervical myoelectric potential as a noise component from the cervical myoelectric potential component directly influenced by driving behavior during driving without directly measuring the cervical myoelectric potential. Removal That.

  According to such a configuration, attention is paid to the fact that the driver's face orientation angle has a correlation with the cervical myoelectric potential, and before driving, the brain wave data in the driver's resting state and the face orientation angle are associated with each other in the neck. By accumulating in the cervical myoelectric potential accumulating unit 140, the electroencephalogram data in a resting state before driving can be estimated as the cervical myoelectric potential.

  Further, during driving, the cervical myoelectric potential estimation unit 150 uses the cervical myoelectric potential storage unit 140 to estimate the cervical myoelectric potential corresponding to the driver's face orientation angle. This makes it possible to measure EEG during driving by directly removing cervical myoelectric potential, which is directly affected by driving behavior during driving, from EEG data as a noise component, without directly measuring cervical myoelectric potential. Become.

  As described above, the cervical myoelectric potential estimation unit 150 uses the cervical myoelectric potential data stored in the cervical myoelectric potential storage unit 140 before driving and the face direction change amount measured by the face measuring unit 130 during driving. Estimate myoelectric component (cervical myoelectric potential). The electroencephalogram signal processing unit 160 removes the cervical myoelectric potential from the electroencephalogram data, thereby making it possible to measure the electroencephalogram during driving without directly measuring the cervical myoelectric potential.

  The above description is an illustration of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this.

  For example, in the above-described embodiment, the engine operation determination unit 110 is provided in order to store the brain wave data and the face orientation angle in a resting state before driving in association with the cervical myoelectric potential storage unit 140. It is only necessary to have a configuration in which the brain wave data and the face orientation angle in a calm state are associated with each other and stored in the cervical myoelectric potential storage unit 140 without the engine operation determination unit 110. It can also be applied to.

  Moreover, as long as it is a response | compatibility which accumulate | stores beforehand the data measured in places other than a driving | operation or other than a driving | operation, what kind of aspect may be sufficient. However, the measurement conditions vary greatly depending on the position of the electrode attached to the head. For this reason, it is preferable to measure the difference between the resting state before driving and during driving without changing the electrode attachment position.

  In this embodiment, the names of an electroencephalogram estimation apparatus and an electroencephalogram estimation method are used. However, this is for convenience of explanation, and the apparatus is an electroencephalogram measurement apparatus from which cervical myoelectric potential is removed, and the method is cervical myoelectric potential estimation. It may be a method or the like.

  Further, each component constituting the above-described brain wave estimation apparatus, for example, the type of engine operation determination, the measurement method of the face direction measurement unit, and the like are not limited to the above-described embodiment.

  The electroencephalogram estimation method described above is also realized by a program for causing the electroencephalogram estimation method to function. This program is stored in a computer-readable recording medium.

  The electroencephalogram estimation apparatus and the electroencephalogram estimation method according to the present invention have the effect of removing, from the electroencephalogram data, the cervical myoelectric potential directly affected by driving behavior as a noise component without directly measuring the cervical myoelectric potential. It is useful as an electroencephalogram measurement application for detecting a decrease in arousal during driving, monotonous fatigue, distraction, and the like. In addition, the electroencephalogram measurement apparatus having the face orientation measuring unit can be applied to warning applications such as aside looking and falling asleep while driving. Furthermore, it can be applied to cases other than driving using the neck, such as when watching TV or engaging in video surveillance.

DESCRIPTION OF SYMBOLS 100 Electroencephalogram estimation apparatus 110 Engine operation | movement determination part 120 Electroencephalogram measurement part 130 Face direction measurement part 140 Neck part myoelectric potential accumulation part 150 Neck part myoelectric potential estimation part 160 EEG signal processing part

Claims (12)

An electroencephalogram measurement unit for measuring an electroencephalogram,
A face orientation measurement unit for measuring the face orientation angle;
A cervical myoelectric potential estimation unit that estimates a cervical myoelectric potential according to the face orientation angle measured by the face orientation measuring unit;
An electroencephalogram signal processing unit for removing the cervical myoelectric potential estimated by the cervical myoelectric potential estimation unit from the electroencephalogram data measured by the electroencephalogram measurement unit, as a noise component;
An electroencephalogram estimation apparatus comprising:   The electroencephalogram estimation apparatus according to claim 1, further comprising a cervical myoelectric potential accumulating unit that accumulates cervical myoelectric potential data in association with the face orientation angle measured by the face orientation measuring unit and the electroencephalogram data measured by the electroencephalogram measuring unit. .   The cervical myoelectric potential estimator refers to cervical myoelectric potential data stored in the cervical myoelectric potential accumulator, and estimates cervical myoelectric potential according to the face orientation angle measured by the face orientation measuring unit. The electroencephalogram estimation apparatus according to claim 2. An engine operation determination unit for determining whether or not the vehicle engine is started,
The neck myoelectric potential estimation unit,
When the engine operation determination unit determines that the engine of the vehicle has not started, the face angle measured by the face direction measurement unit and the electroencephalogram data are associated with each other and stored in the cervical myoelectric potential storage unit, The electroencephalogram estimation apparatus according to claim 2, wherein when it is determined that the engine is started, a cervical myoelectric potential is estimated according to a face orientation angle measured by the face orientation measurement unit. An engine operation determination unit for determining whether or not the vehicle engine is started,
The electroencephalogram signal processor is
When it is determined by the engine operation determination unit that the vehicle engine is started, the cervical myoelectric potential estimated by the cervical myoelectric potential estimation unit is removed as a noise component from the electroencephalogram data measured by the electroencephalogram measurement unit. The electroencephalogram estimation apparatus according to claim 1. The face direction measurement unit measures the angle when the face direction is moved laterally from the central axis of the head in a resting state before driving,
The electroencephalogram estimation apparatus according to claim 1, wherein the cervical myoelectric potential accumulation unit accumulates the measured angle in association with the electroencephalogram data. The cervical myoelectric potential estimation unit estimates a cervical myoelectric potential component corresponding to an angle when the face is moved laterally from the central axis of the head during driving,
The electroencephalogram estimation apparatus according to claim 1, wherein the electroencephalogram signal processing unit extracts electroencephalogram data from which the myoelectric potential component is removed. The cervical myoelectric potential estimation unit linearly complements the amount of change in angle and the myoelectric potential component when the face is moved laterally from the central axis of the head at the time of driving. Estimate
The electroencephalogram estimation apparatus according to claim 1, wherein the electroencephalogram signal processing unit extracts electroencephalogram data from which the myoelectric potential component is removed. The cervical myoelectric potential estimation unit estimates the cervical myoelectric potential component by linearly complementing the moving speed and myoelectric potential component when the face is moved laterally from the central axis of the head during driving. And
The electroencephalogram estimation apparatus according to claim 1, wherein the electroencephalogram signal processing unit extracts electroencephalogram data from which the myoelectric potential component is removed. Measuring brain waves,
Measuring the face angle; and
A cervical myoelectric potential estimating step for estimating a cervical myoelectric potential according to the measured face orientation angle;
Removing the cervical myoelectric potential estimated from the measured electroencephalogram data as a noise component. Further comprising the step of storing the measured face orientation angle and the measured electroencephalogram data in association with each other as cervical myoelectric potential data,
The electroencephalogram estimation method according to claim 10, wherein in the cervical myoelectric potential estimation step, the cervical myoelectric potential is estimated according to the measured face orientation angle with reference to the accumulated cervical myoelectric potential data. The program for making a computer perform each step of the electroencephalogram estimation method of Claim 10 or Claim 11.

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