Search

CN-122004866-A - Fatigue driving intervention method and system based on head electrical stimulation

CN122004866ACN 122004866 ACN122004866 ACN 122004866ACN-122004866-A

Abstract

The invention discloses a fatigue driving intervention method and a system based on head electric pulse stimulation, which relate to the technical field of fatigue driving intervention and comprise the steps of acquiring scalp inching frequency and scalp-electrode impedance change of a driver through a head-mounted sensing device to obtain an original physiological state signal; the method comprises the steps of calculating a current fatigue index according to an original physiological state signal, wherein scalp inching frequency reduction and impedance fluctuation amplitude increase correspond to fatigue degree increase and attention dispersion aggravation respectively, continuously comparing the fatigue index with a dynamically adjusted physiological threshold value, generating a first intervention trigger condition when the fatigue index exceeds the physiological threshold value and maintains for a preset duration, judging whether a second intervention trigger condition or a third intervention trigger condition is generated according to an intervention mode preset by a user, vehicle continuous running time and a manual trigger instruction, and outputting an intervention enabling signal based on a logic relation among the first intervention trigger condition, the second intervention trigger condition and the third intervention trigger condition.

Inventors

  • YE ZHIWEI

Assignees

  • 叶志伟

Dates

Publication Date
20260512
Application Date
20260202

Claims (10)

  1. 1. A fatigue driving intervention method based on forehead electrical stimulation is characterized by comprising the following steps: Acquiring an original physiological state signal from EEG signals of the forehead of a driver through a head-mounted sensing device; Calculating a current fatigue index according to the ratio of the low-frequency component to the high-frequency component in the original physiological state signal, wherein the reduction of the fatigue index corresponds to the increase of the fatigue degree and the increase of the distraction; continuously comparing the fatigue index with a dynamically adjusted physiological threshold, and generating a first intervention triggering condition when the fatigue index exceeds the physiological threshold and is maintained for a preset period of time; judging whether a first-stage, second-stage or third-stage intervention triggering condition is met according to an intervention mode, vehicle continuous running time and a manual triggering instruction preset by a user, and outputting an electric pulse stimulation instruction signal with a corresponding intensity level according to the grade of the met triggering condition; After receiving the intervention enabling signal, detecting the contact impedance between the head-wearing electrode and the forehead skin, outputting short pulse width modulation electric pulse to the connection position between the head-wearing electrode and the forehead skin according to the stimulation intensity level set by a user only when the contact impedance is in an effective conduction interval, accumulating the electric stimulation triggering times in unit time and implementing upper limit locking, and performing intervention and detection periodically. And transmitting the intervention mode, the intervention time and the intensity and the fatigue index to a mobile phone or a vehicle-mounted Bluetooth system through Bluetooth to realize interaction with a user or a management system. The intervention mode, the intervention time and the real-time data of the intensity are stored in the device, at least 24-hour long data are stored, the black box function is realized, and the stored data can be obtained outside through USB or Bluetooth.
  2. 2. The method for intervening in fatigue driving based on electric stimulation of forehead according to claim 1, wherein the step of acquiring EEG signals of forehead of driver through the head-mounted sensing device to obtain the original physiological state signals comprises the following specific steps: after a driver wears intelligent head-mounted equipment integrated with the flexible dry electrode, the system starts an electroencephalogram signal acquisition process; sequentially performing pre-amplification, band-pass filtering (0.5-55 Hz) and power frequency notch processing on the acquired original EEG signals to obtain purified time domain EEG signals; Windowing and segmenting the purified electroencephalogram signals, and performing Fast Fourier Transform (FFT) on each segment to obtain power spectral density in the range of 1-55 Hz; Extracting alpha wave band (8-12 Hz) and Average power values of the bands (12-25 Hz), respectively, are recorded as And (3) with ; Will be And (3) with As a key feature of the original physiological status signal.
  3. 3. The method for intervention in fatigue driving based on electrical stimulation of forehead according to claim 2, wherein the calculating the current fatigue index based on the original physiological state signal comprises the following specific steps: Calculating spectral ratios ; Setting a reference ratio in a awake state ; For a pair of Normalized mapping is carried out to obtain fatigue index The expression is: ; Wherein, the E [0, 100], lower values indicating higher fatigue; The fatigue index The value of (2) corresponds to the following state: 90-100 means fully awake; 80-90 indicates slight fatigue; 70-80 represent moderate fatigue; 60-70 represents deep fatigue; 40-60 represent deep sleep tendencies; <40 represents a deep unconscious risk; the said The system is configured by a user through a serial touch screen or loaded by adopting factory default values in the system initialization stage.
  4. 4. The method for intervention in fatigue driving based on electrical stimulation of forehead according to claim 3, wherein the step of continuously comparing the fatigue index with a dynamically adjusted physiological threshold value and generating a first intervention trigger condition when the fatigue index is lower than the physiological threshold value for a preset period of time comprises the steps of: Setting the initial physiological threshold as ∈[75, 85]; Introducing environmental correction factors If the vehicle start time is at night (22:00-6:00), then = >0, Otherwise α=0; Introducing a behavior feedback correction factor beta, wherein the system records whether a driver stops and rests within 5 minutes after K times of intervention, if the number of times of rest is not more than 50%, beta=beta_high > 0, otherwise, beta=0; Dynamically updating physiological thresholds The method comprises the following steps: ; the system is sampling period Continuous monitoring of fatigue index If it is continuous Each cycle satisfies < And judging that the continuous overrun condition is met, and generating a first intervention triggering condition.
  5. 5. The method for intervention in fatigue driving based on head electrical stimulation of claim 4, wherein the method is characterized by combining an intervention Mode preset by a user, continuous running time of a vehicle and a manual trigger instruction, judging whether to generate a second intervention trigger condition or a third intervention trigger condition, and outputting an intervention enabling signal based on a logic relation among the first intervention trigger condition, the second intervention trigger condition and the third intervention trigger condition; if mode=active, then starting the vehicle running timer, when the accumulated continuous running time is not less than Generating a second intervention trigger condition; If mode=passive, continuously monitoring a physical key signal on the head-mounted device, and generating a third intervention triggering condition when an effective press is detected and the duration is greater than the debounce threshold; if mode=hybrid, outputting an intervention enabling signal when either the first intervention triggering condition or the second intervention triggering condition is established; Upon detection of a manual trigger instruction, the intervention enable signal is immediately set and the running timer is cleared, with priority over other conditions.
  6. 6. The method for intervention in fatigue driving based on electrical stimulation of head as set forth in claim 5, wherein after receiving the intervention enabling signal, detecting contact impedance between the head-wearing electrode and the forehead skin, outputting pulse width modulation electrical pulse to the specific region of the head according to the stimulation intensity level set by the user only when the contact impedance is in the effective conduction interval, and accumulating the electrical stimulation triggering times in unit time and implementing upper limit locking, comprising the following specific steps: applying an alternating excitation voltage with constant amplitude and fixed frequency to the electrodes Measuring loop current Calculating contact impedance ; Setting the effective conduction interval as ; If it is ≤ ≤ Judging that the electrode is well attached, and allowing the electric stimulation to be output; otherwise, forbidding output and prompting that the electrode is not attached on the display screen; If the bonding is good, the stimulation intensity level set by the user is read Wherein =1 To 5, corresponding to 5-gear output current; the drive booster circuit and the H bridge output bipolar square wave pulse with fixed frequency Duration of single stimulus Second, wherein the second is; Hourly trigger counter for system maintenance Check before each output < ; If true, then execute the stimulus and ; Otherwise, the locking state is entered until the next hour is automatically reset.
  7. 7. The method for intervening fatigue driving based on head electric stimulation according to claim 6, wherein the intervening mode type, the time count value, the history stimulation record and the electrode contact state are transmitted to a serial touch display screen through serial communication, and are presented on the screen in real time for user interaction configuration, and the method comprises the following specific steps: the main control module packs current operation data in a fixed frame format, wherein the current operation data comprises an intervention mode identifier, a vehicle continuous operation time, a last five intervention time stamp, a current contact impedance, an hour trigger count and a locking flag bit; transmitting the data to a serial touch display screen through a UART interface at 9600 baud rate; the display screen analyzes the data and updates the data at the UI interface, and the method comprises the following steps: A mode icon running time progress bar, an intervention record list and a contact state indicator lamp; When the user operates the slider or button, a setlevel =l or setmode =mode instruction is generated; Writing the main control into an internal EEPROM after receiving and immediately effecting the next intervention flow; all intervention events, fatigue indexes and mode switching logs are locally stored for more than or equal to 24 hours, and are exported through USB or Bluetooth, so that the black box function is realized.
  8. 8. The fatigue driving intervention system based on the head electric stimulation and the fatigue driving intervention method based on the head electric stimulation as claimed in any one of claims 1 to 7 are characterized by comprising a physiological signal acquisition module, a fatigue index calculation module, a dynamic threshold judgment module, a dual-mode intervention decision module, a safety electric stimulation execution module and a human-computer interaction display module; The physiological signal acquisition module is used for acquiring the brain electrical signals of the forehead area of the driver in real time through a flexible electrode on the head-mounted sensing device, performing digital conversion after amplifying and filtering the signals, performing spectrum analysis on the brain electrical signals within a set time window, and extracting high-frequency brain electrical components related to a wakeful state and low-frequency brain electrical components related to a relaxed or drowsy state to form an original physiological state signal for fatigue evaluation; The fatigue index calculation module is used for calculating a fatigue index reflecting the brain activity degree according to the power proportion relation of the high-frequency brain electrical component and the low-frequency brain electrical component, wherein the higher the fatigue index is, the more awake the driver is, the lower the fatigue index is, the more serious the fatigue degree is and the more distraction is, and the fatigue index is counted to be a value between zero and one hundred; The dynamic threshold judging module is used for continuously comparing the current fatigue index with a dynamically adjusted physiological threshold, the physiological threshold automatically corrects the response behavior of the intervention prompt according to whether the vehicle starting time is at night or not and whether the driver passes the intervention prompt, and when the fatigue index is lower than the physiological threshold and continuously reaches a preset duration, a first intervention triggering condition is generated; The dual-mode intervention decision module is used for judging whether to output an intervention enabling signal according to preset priority logic by combining the continuous operation time length of the vehicle, a manual triggering instruction and the first intervention triggering condition according to an intervention mode selected by a user in advance; The safety electric stimulation execution module is used for detecting the contact impedance between the head-wearing electrode and the forehead skin after receiving the intervention enabling signal, outputting short-duration electric pulse stimulation to the forehead area according to the intensity level set by a user only when the impedance is in an effective conduction range, counting the triggering times of the electric stimulation in each hour, and stopping outputting until the next hour is reset once the upper limit is reached; The man-machine interaction display module is used for receiving the setting of the intervention mode and the stimulus intensity by a user through a touch display screen connected with a serial port, displaying the current fatigue state, the running timing, the latest intervention records for a plurality of times, the electrode contact state and whether the current fatigue state, the running timing, the electrode contact state and the electrode contact state are in a triggering locking state or not in real time, and realizing the bidirectional interaction functions of parameter configuration, state feedback and data persistence storage.
  9. 9. The computer equipment comprises a memory and a processor, wherein the memory stores a computer program, and the computer program is characterized in that the processor realizes the steps of the fatigue driving intervention method based on the head electrical stimulation according to any one of claims 1-7 when executing the computer program.
  10. 10. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the fatigue driving intervention method based on head electrical stimulation as claimed in any one of claims 1-7.

Description

Fatigue driving intervention method and system based on head electrical stimulation Technical Field The invention relates to the technical field of fatigue driving intervention, in particular to a fatigue driving intervention method and system based on head electrical stimulation. Background The fatigue driving intervention technology is an intelligent safety technology for preventing traffic accidents caused by slow response, misjudgment or short sleep due to fatigue by monitoring the physiological state or driving behavior of a driver and actively adopting physical, acousto-optic or nerve stimulation means and the like after the fatigue symptom is identified and waking up the attention of the driver in time to promote the rest of the driver. Therefore, how to improve the intelligent level and safety of fatigue driving intervention by using advanced technical means is one of the problems to be solved in the current urgent need. In the field of fatigue driving intervention, the prior art mostly depends on a single external behavior signal, is easy to be interfered by illumination, shielding, driving habit or vehicle type, can not truly reflect the fatigue state of a central nervous system of a driver, and has high false alarm rate or serious missing alarm, most systems adopt a fixed time threshold or a general fatigue model, do not consider individual physiological differences, circadian rhythms or historical response behaviors, and are difficult to realize the intervention on demand. Disclosure of Invention The present invention has been made in view of the above-described problems occurring in the prior art. Therefore, the invention provides a fatigue driving intervention method based on head electrical stimulation, which solves the problems that the prior art depends on single external behavior signals, is easy to be interfered by illumination, shielding, driving habit or vehicle type, cannot truly reflect the fatigue state of a central nervous system of a driver, and has high false alarm rate or serious false alarm, and most systems adopt fixed time threshold or general fatigue models, do not consider individual physiological differences, circadian rhythms or historical response behaviors, and are difficult to realize on-demand intervention. In order to solve the technical problems, the invention provides the following technical scheme: In a first aspect, the invention provides a fatigue driving intervention method based on head electrical stimulation, comprising: Acquiring scalp micro-motion frequency and scalp-inter-electrode impedance change of a driver through a head-mounted sensing device to obtain an original physiological state signal; Calculating a current fatigue index according to the original physiological state signal, wherein the scalp micro-motion frequency decrease and the impedance fluctuation amplitude increase correspond to the fatigue degree increase and the attention dispersion aggravation respectively; continuously comparing the fatigue index with a dynamically adjusted physiological threshold, and generating a first intervention triggering condition when the fatigue index exceeds the physiological threshold and is maintained for a preset period of time; judging whether to generate a second intervention trigger condition or a third intervention trigger condition according to an intervention mode preset by a user, the continuous running time of the vehicle and a manual trigger instruction, and outputting an intervention enabling signal based on the logic relation among the first intervention trigger condition, the second intervention trigger condition and the third intervention trigger condition; After receiving the intervention enabling signal, detecting the contact impedance between the head cover electrode and the scalp, outputting pulse width modulation electric pulse to a specific area of the head according to the stimulation intensity level set by a user only when the contact impedance is in an effective conduction interval, and accumulating the electric stimulation triggering times in unit time and implementing upper limit locking; the intervention mode type, the time count value, the historical stimulation record and the electrode contact state are transmitted to a serial touch display screen through serial communication, and the configuration is presented on the screen in real time for user interaction. The head electric stimulation-based fatigue driving intervention method is characterized by comprising the following steps of collecting scalp micro-motion frequency and scalp-electrode impedance change of a driver through a head-mounted sensing device to obtain an original physiological state signal, wherein the method comprises the following specific steps of: after the driver wears the intelligent headgear integrated with the flexible electrode, the system starts a physiological signal acquisition process; In the time window In the interior, the micro-vibration sensor cont