Disclosure of Invention
In view of the above, the invention provides a maneuver decision modeling method based on multi-modal physiological information, which is used for solving the problems of large workload, excessive rationality and low fidelity of the conventional maneuver decision modeling method.
Therefore, the invention provides a maneuvering decision modeling method based on multi-modal physiological information, which comprises the following steps:
s1: building a real person immersive combat simulation scene;
s2: carrying out experimental design on the collection of the multi-modal physiological information; the multi-modal physiological information comprises an electroencephalogram signal, an eye movement signal and an electrocardiosignal;
s3: collecting the multi-modal physiological information;
s4: preprocessing the acquired electroencephalogram signals;
s5: extracting and screening the collected eye movement signals, the electrocardiosignals and the characteristics of the preprocessed electroencephalogram signals;
s6: and constructing a behavior maneuver decision model by adopting a support vector machine mode.
In a possible implementation manner, in the maneuver decision modeling method provided by the present invention, in step S2, the experimental design of the collection of the multi-modal physiological information specifically includes:
s21: recruiting the testees, and screening according to the physiological conditions and task experience of the testees;
s22: carrying out task training on the screened tested object, judging whether the tested object learns the basic operation of the flight simulator in an experiment period and independently completing a preset experiment task; if yes, go to step S23; if not, returning to the step S21, and continuing to recruit an equal number of new subjects until the number of the subjects reaches the standard;
s23: performing a pre-experiment on a tested object, checking a training result of the tested object and checking feasibility of experimental design;
s24: and carrying out formal experiments on the tested object, sequentially completing each experiment task according to a preset experiment sequence, and collecting multi-modal physiological experiment data when a person executes a maneuver decision.
In a possible implementation manner, in the maneuver decision modeling method provided by the present invention, in step S4, the preprocessing is performed on the acquired electroencephalogram signal, which specifically includes:
s41: preprocessing the acquired electroencephalogram signal by utilizing an MATLAB open source tool box to obtain an noiseless electroencephalogram signal;
s42: and storing the noiseless electroencephalogram signals.
In a possible implementation manner, in the above maneuvering decision modeling method provided by the present invention, step S41, the acquired electroencephalogram signal is preprocessed by using an open source toolbox of MATLAB, so as to obtain an electroencephalogram signal without noise, which specifically includes:
and carrying out electrode positioning, band-pass filtering, superposition averaging, baseline correction, re-referencing and independent component analysis on the acquired electroencephalogram signals by utilizing an open source tool box of MATLAB to obtain noiseless electroencephalogram signals.
In a possible implementation manner, in the above maneuvering decision modeling method provided by the present invention, step S5, the extracting and screening features of the collected eye movement signal, the collected electrocardiographic signal, and the preprocessed electroencephalogram signal specifically includes:
s51: for electroencephalogram signals with different maneuvering decisions, extracting and screening the characteristics of the electroencephalogram signals by adopting a time-frequency characteristic extraction method, a self-adaptive regression method, a common spatial mode method and a power spectrum analysis method;
s52: extracting and screening the blink rate characteristic, the fixation rate characteristic, the average fixation duration characteristic and the average pupil diameter characteristic of the eye movement signals for different maneuver decisions;
s53: extracting and screening the characteristics of the electrocardiosignals with different maneuvering decisions by respectively adopting a time domain analysis method, a frequency domain analysis method and a nonlinear analysis method;
s54: and summarizing the characteristics of the screened electroencephalogram signals, the characteristics of the eye movement signals and the characteristics of the electrocardiosignals to form multi-mode mixed physiological characteristics.
In a possible implementation manner, in the maneuver decision modeling method provided by the present invention, in step S52, for eye movement signals of different maneuvers, extracting a blink rate feature, a gaze rate feature, an average gaze duration feature, and an average pupil diameter feature of the eye movement signals specifically includes:
calculating the blink rate f of eye movement using the following formulabIs characterized in that:
wherein n represents the total number of winks and T represents the total time of the task;
the fixation rate f of eye movement is calculated using the following formulagIs characterized in that:
wherein m represents the total number of fixations;
the average duration of gaze of the eye movement is calculated using the following formula
Is characterized in that:
wherein d isfiRepresents the duration of the ith gaze activity;
the average pupil diameter of the eye movement is calculated using the following formula
Is characterized in that:
wherein ldiRepresenting the measured pupil diameter size during the i-th fixation activity.
In a possible implementation manner, in the maneuver decision modeling method provided by the present invention, after the step S6 is executed, a behavior maneuver decision model is constructed in a support vector machine manner, the method further includes the following steps:
s7: performing model training on the behavior maneuver decision model by adopting a cross validation mode;
s8: and optimizing the parameters of the behavior maneuver decision model by adopting an optimization algorithm of grid search.
The maneuvering decision modeling method provided by the invention directly extracts multi-modal physiological information from the process of executing maneuvering actions by people, constructs a model, does not depend on experience summary of domain experts and knowledge discovery of a computer, can reduce the workload of people and save labor cost compared with the traditional modeling mode which depends on the experience summary of the domain experts, and has the characteristic of perceptual transformation from pure rationality compared with the modeling mode which depends on the knowledge discovery of the computer, so that the established model has higher fidelity and is closer to the behavior decision process of people; in addition, the maneuvering decision modeling is carried out by utilizing the multi-modal physiological information, and the problem that the maneuvering decision modeling by utilizing a single physiological signal has one-sidedness can be solved; in addition, an important advantage of utilizing multimodal physiological information is the objectivity of the characteristics, and compared with the traditional modeling mode which depends on a domain expert experience summary formula, the acquired data is more real and reliable, and the real maneuvering decision process of a person can be reflected more objectively.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only illustrative and are not intended to limit the present application.
The maneuvering decision modeling method based on the multi-modal physiological information provided by the embodiment of the invention has the flow diagram and the flow chart respectively shown in fig. 1 and fig. 2, and comprises the following steps:
s1: building a real person immersive combat simulation scene;
s2: carrying out experimental design on the collection of multi-modal physiological information; the multi-modal physiological information comprises an electroencephalogram signal, an eye movement signal and an electrocardiosignal;
s3: collecting multi-modal physiological information;
s4: preprocessing the acquired electroencephalogram signals;
s5: extracting and screening the characteristics of the collected eye movement signals, the collected electrocardiosignals and the preprocessed electroencephalogram signals;
s6: and constructing a behavior maneuver decision model by adopting a support vector machine mode.
The maneuvering decision modeling method provided by the embodiment of the invention directly extracts multi-modal physiological information from the process of executing maneuvering actions by people, constructs the model, does not depend on experience summary of domain experts and knowledge discovery of a computer, can reduce the workload of people and save labor cost compared with the traditional modeling mode which depends on the experience summary of the domain experts, and has the characteristic of being perceptual after being converted from pure rationality compared with the modeling mode which depends on the knowledge discovery of the computer, so that the established model has higher fidelity and is closer to the behavior decision process of people; in addition, the maneuvering decision modeling is carried out by utilizing the multi-modal physiological information, and the problem that the maneuvering decision modeling by utilizing a single physiological signal has one-sidedness can be solved; in addition, an important advantage of utilizing multimodal physiological information is the objectivity of the characteristics, and compared with the traditional modeling mode which depends on a domain expert experience summary formula, the acquired data is more real and reliable, and the real maneuvering decision process of a person can be reflected more objectively. The maneuver decision modeling method provided by the embodiment of the invention benefits from the rapid development of neuroengineering, particularly the improvement of physiological signal acquisition equipment such as electroencephalogram signals, eye movement signals, electrocardiosignals and the like and the great development of signal processing methods, and promotes the detection research of behavior physiological information.
In specific implementation, step S1 in the maneuver decision modeling method provided in the embodiment of the present invention builds an experimental simulation scene, and provides a real-person immersive simulation environment for a test to assist the test in making an effective maneuver decision. Specifically, an experimental simulation scene can be set up by taking the experimental purpose of modeling the human maneuver as a starting point. Taking an aircraft simulator as an example, the aircraft simulator comprises a visual system, an air combat simulator cockpit and a computer network system. The visual scene system adopts a computer imaging system to generate visual scenes outside a battle base cabin, mainly comprises landforms such as airport runways, buildings, fields, roads and the like, and can carry out simulation on battle scenes under complex conditions, such as rainy days, snowy days and thunderstorm days, and scenes in daytime and night modes. The appearance of the cabin of the air war simulator adopts a full-cover type cabin, and various instrument panels, operating devices and unmanned aerial vehicle seats are arranged in the cabin; the instrument panel can be divided into an instrument module, a central console module and a control panel according to a functional structure and a functional module; the control panel is a multifunctional display, and the main flight display panel is symmetrically arranged according to the driving position; the operating device comprises a throttle lever, a handle, pedals and the like, and is symmetrically arranged according to the driving position. The computer network system is the core of the whole airplane simulator, the hardware comprises a host, an interface and a bus, the software comprises software management, application software and support software, the software comprises a scene computer, a server computer and a central control computer, and the three computers are mutually matched through Ethernet to perform real-time data exchange and cooperate with each other to complete a flight simulation task.
In specific implementation, when step S2 of the maneuver decision modeling method provided by the embodiment of the present invention is performed to design an experiment for collecting multi-modal physiological information, a specific experimental process may include four stages of a subject recruitment stage, a subject training stage, a pre-experiment stage, and a formal experiment stage (as shown in fig. 3), and step S2, as shown in fig. 4, may be specifically implemented in the following manner:
s21: recruiting the testees, and screening according to the physiological conditions and task experience of the testees;
specifically, the requirement of the experiment on the subject is high and the experiment is limited to a specific population, so that the subject needs to be screened strictly according to the physiological conditions and task experience of the subject when being recruited;
s22: carrying out task training on the screened tested object, judging whether the tested object learns the basic operation of the flight simulator in an experiment period and independently completing a preset experiment task; if yes, go to step S23; if not, returning to the step S21, and continuing to recruit an equal number of new subjects until the number of the subjects reaches the standard;
specifically, the tested person needs to learn the basic operation of the flight simulator in the experimental period and independently complete the preset experimental task, and if the tested person cannot successfully complete the training, an equal number of new tested persons need to be recruited until the number of the tested persons reaches the standard;
s23: performing a pre-experiment on a tested object, checking a training result of the tested object and checking feasibility of experimental design;
specifically, the main test controls the experiment time and the experiment process through the pre-experiment, and fine adjustment improvement of the subsequent process is carried out according to the pre-experiment condition;
s24: and carrying out formal experiments on the tested object, sequentially completing each experiment task according to a preset experiment sequence, and collecting multi-modal physiological experiment data when a person executes a maneuver decision.
In specific implementation, when step S4 in the maneuver decision modeling method provided by the embodiment of the present invention is executed to perform preprocessing on the acquired electroencephalogram signal, as shown in fig. 4, the preprocessing may be specifically implemented in the following manner:
s41: preprocessing the acquired electroencephalogram signals by utilizing an MATLAB open source tool box to obtain noiseless electroencephalogram signals;
specifically, the open source toolbox for MATLAB may be Letswave;
s42: storing the noise-free electroencephalogram signals;
in particular, it can be stored in txt format.
In specific implementation, when the step S41 in the above-described maneuver decision modeling method provided in the embodiment of the present invention is executed, and the acquired electroencephalogram signal is preprocessed by using the MATLAB open source kit to obtain a noiseless electroencephalogram signal, the acquired electroencephalogram signal may be specifically subjected to electrode localization, band-pass filtering, superposition averaging, baseline correction, re-referencing, and independent component analysis by using the MATLAB open source kit to obtain a pure noiseless electroencephalogram signal as much as possible, and a preprocessing flow diagram based on the electroencephalogram signal is shown in fig. 5.
In specific implementation, when step S5 in the maneuver decision modeling method provided by the embodiment of the present invention is executed to extract and screen features of the acquired eye movement signal, the acquired electrocardiogram signal, and the preprocessed electroencephalogram signal, as shown in fig. 4, the following methods may be specifically implemented:
s51: for electroencephalogram signals with different maneuvering decisions, extracting and screening the characteristics of the electroencephalogram signals by adopting a time-frequency characteristic extraction method, a self-adaptive regression method, a common spatial mode method and a power spectrum analysis method;
specifically, when a time-frequency analysis method is adopted, the characteristics of five frequency bands of the electroencephalogram signals can be extracted by adopting a relatively classical Fast Fourier Transform (FFT), a short-time fourier transform (STFT) and a wavelet transform method, and the extracted frequency domain characteristics comprise frequency sub-bands of five wave bands of alpha waves, beta waves, delta waves, theta waves and gamma waves. The method comprises the steps of selecting the strongest frequency characteristic as a characteristic alternative by comparing the strength of the frequency characteristics among different time-frequency methods, then comparing the characteristic alternative with the characteristics of an adaptive regression model, a common spatial mode, power spectrum analysis, energy mean value and variance analysis in a significance difference mode, selecting the characteristics with significance difference among different maneuver decision characteristics as standby characteristics established by the model, and effectively decoding the maneuver decision intention of a person by the screened characteristics. The technical route of feature extraction based on electroencephalogram signals is shown in fig. 6;
s52: extracting and screening the blink rate characteristic, the fixation rate characteristic, the average fixation duration characteristic and the average pupil diameter characteristic of the eye movement signals for different maneuver decisions;
in particular, eye movement signals of different manoeuvres are another good indicator of the human-machine-action behavior of the decoding. The characteristics of the eye movement signal mainly include blink rate, pupil size, average fixation time of fixation point, and the like. In the course of performing maneuvers, the person's blink rate shows a decreasing trend as he performs stressful emotions. When the same task is completed, the pupils of the people can be expanded firstly due to the influence of time pressure; as the combat mission progresses, the person gradually becomes tired and the pupil shrinks. Therefore, the processing of the eye movement signals finally selects the blink rate, the fixation rate, the average fixation duration and the average pupil diameter as main analysis characteristics. The characteristics of the eye movement signals are screened, the characteristics with significant differences among different maneuver decisions are selected, and the change of the eye movement signals is helpful for comprehensively decoding the situations of attention maintenance, conversion and distribution when a person performs a maneuver. The technical route of feature extraction based on eye movement signals is shown in fig. 7;
s53: extracting and screening the characteristics of the electrocardiosignals with different maneuvering decisions by respectively adopting a time domain analysis method, a frequency domain analysis method and a nonlinear analysis method;
specifically, electrocardiosignals of different maneuvering decisions are used as another consideration index of the maneuvering of the decoding person. The heart rate variability index is analyzed by adopting three solving methods, namely a time domain analysis method, a frequency domain analysis method and a nonlinear analysis method, so as to identify maneuver decision information contained in behavior decision. The technical route of feature extraction based on electrocardiosignals is shown in fig. 8;
the variation of the R-R interval of the electrocardiosignal is calculated by a statistical discrete trend analysis method, namely the interval between two peaks of one heartbeat is the R-R interval. The electrocardiosignal is decomposed into a series of components with different energies and different frequency bands by respectively adopting a time domain analysis method and a frequency domain analysis method and is analyzed, so that the heart rate variability dynamic characteristics missing in a time sequence method can be effectively compensated, the balance action of sympathetic nerves and parasympathetic nerves can be quantitatively judged, and the effect on index sensitivity and specificity is better;
each of the time domain and frequency domain features of the heart rate variability to be used is specifically described below in the form of a table, and as shown in tables 1 and 2, the features of the electrocardiographic signals are screened according to the results. The heart rate variability features provide theoretical basis for establishing a maneuvering decision model for physiological information;
TABLE 1 commonly used heart rate variability time domain characterization table
TABLE 2 commonly used heart rate variability frequency domain characterization table
S54: summarizing the characteristics of the screened electroencephalogram signals, the characteristics of the eye movement signals and the characteristics of the electrocardiosignals to form multi-mode mixed physiological characteristics; as shown in fig. 9, this provides a basis for the construction of the maneuver decision model of step S5.
It should be noted that the key of modeling is the similarity to the real situation, and modeling that does not conform to the real situation loses the existing value. On the premise of rapid development of the current physiological measurement technology, the maneuver decision modeling method provided by the embodiment of the invention can comprehensively measure various physiological indexes of a person in a maneuver decision, and can measure physiological signals directly or indirectly related to central nervous system activities, such as a skin electrical signal, a respiratory wave, a functional near infrared spectrum and the like, besides an electroencephalogram signal, an oculomotor signal and an electrocardio signal. The method comprises the steps of processing multi-modal physiological information by utilizing various physiological information processing methods, decoding human brain through extracting characteristics of electroencephalogram signals to perform a decision process during information processing, analyzing attention of a human in a task execution process through extracting characteristics of eye movement signals, extracting psychological conditions of motor decision of the human through characteristics of electrocardiosignals, combining the characteristics of the multi-modal physiological information to serve as fusion characteristics, reflecting diversity of multi-modal behavior characteristics, and playing an important role in motor decision modeling. The invention constructs the behavior model by fusing the multi-modal characteristics of the electroencephalogram signal, the eye movement signal and the electrocardiosignal of the human behavior, and the constructed maneuver decision model directly obtains maneuver decision data from the human body, does not depend on the summary of field experts and the knowledge discovery of a computer, can overcome the defects of low fidelity and excessive rationality of the human behavior model, and can solve the problem that the maneuver decision modeling by using a single physiological signal has one-sidedness.
In specific implementation, in step S52 of the maneuver decision modeling method provided in the embodiment of the present invention, for eye movement signals of different maneuvers, a blink rate feature, a gaze rate feature, an average gaze duration feature, and an average pupil diameter feature of the eye movement signals are extracted, where the blink rate refers to a number of blinks in a unit time, generally speaking, a closed-eye behavior of a person lasting 70 to 500ms may be regarded as a single blink, and specifically, a blink rate f of the eye movement may be calculated by using the following formulabIs characterized in that:
wherein n represents the total number of winks and T represents the total time of the task;
the fixation rate of eye movement is the number of fixations per unit time, and may be regarded as one fixation with a duration of not less than 100ms, and specifically, the fixation rate f of eye movement may be calculated by using the following formulagIs characterized in that:
wherein m represents the total number of fixations;
the average duration of the fixation of the eye movement refers to the average duration of each fixation behavior, and the average duration of the fixation of the eye movement can be calculated by using the following formula
Is characterized in that:
wherein d isfiRepresents the duration of the ith gaze activity;
the average pupil diameter of the eye movement refers to the average value of all pupil diameter measurement results, and the eye movement acquisition equipment measures the eye movement once during each individual gazing behavior, and particularly, the average pupil diameter of the eye movement can be calculated by the following formula
Is characterized in that:
wherein ldiRepresenting the measured pupil diameter size during the i-th fixation activity.
In specific implementation, in step S6 of the maneuver decision modeling method provided in the embodiment of the present invention, in the behavior maneuver decision model is constructed in a support vector machine manner, the support vector machine manner has good classification performance and excellent generalization capability, and pseudo codes of the construction process are shown in table 3.
Table 3: support vector machine classifier pseudo code
In specific implementation, after the step S6 in the maneuver decision modeling method provided by the embodiment of the present invention is executed, and a behavior maneuver decision model is constructed in a support vector machine manner, as shown in fig. 4, the method may further include the following steps:
s7: performing model training on the behavior maneuver decision model by adopting a cross validation mode;
specifically, in order to prevent overfitting of the maneuvering model, a cross validation mode is adopted for model training in the model training process;
s8: optimizing parameters of the behavior maneuver decision model by adopting an optimization algorithm of grid search; therefore, the identification accuracy can be further improved, and the behavior maneuver model can be more accurately established for the multi-modal physiological information.
From the view point of model construction, the maneuvering decision model based on the multi-modal physiological information takes the multi-modal physiological mixed characteristics of maneuvering decision as model input, and is richer than the input of the maneuvering decision model established by traditional single physiological signals. The output results based on different maneuver decisions as models are shown in FIG. 10.
The maneuvering decision modeling method provided by the embodiment of the invention directly extracts multi-modal physiological information from the process of executing maneuvering actions by people, constructs the model, does not depend on experience summary of domain experts and knowledge discovery of a computer, can reduce the workload of people and save labor cost compared with the traditional modeling mode which depends on the experience summary of the domain experts, and has the characteristic of being perceptual after being converted from pure rationality compared with the modeling mode which depends on the knowledge discovery of the computer, so that the established model has higher fidelity and is closer to the behavior decision process of people; in addition, the maneuvering decision modeling is carried out by utilizing the multi-modal physiological information, and the problem that the maneuvering decision modeling by utilizing a single physiological signal has one-sidedness can be solved; in addition, an important advantage of utilizing multimodal physiological information is the objectivity of the characteristics, and compared with the traditional modeling mode which depends on a domain expert experience summary formula, the acquired data is more real and reliable, and the real maneuvering decision process of a person can be reflected more objectively. The maneuver decision modeling method provided by the embodiment of the invention benefits from the rapid development of neuroengineering, particularly the improvement of physiological signal acquisition equipment such as electroencephalogram signals, eye movement signals, electrocardiosignals and the like and the great development of signal processing methods, and promotes the detection research of behavior physiological information.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.