A method for monitoring pilot's physiological state in the air and evaluating flight state

Abstract

The invention relates to a method for monitoring the physiological state of a pilot in the air and evaluating the flight state, and belongs to the field of aviation medical diagnosis. The method comprises the following steps: predetermining a pilot reference value; monitoring φ and six-axis acceleration during flight; calculating an offset ratio in real time based on the reference value; providing a Coriolis illusion risk warning to the pilot in real time based on φ and six-axis acceleration; and obtaining a flight state evaluation result in real time through real-time heart rate, φ and six-axis acceleration.

Description

Technical Field

[0001] The invention relates to the technical field of aviation medical diagnosis, and in particular to a method for monitoring a pilot's physiological state in the air and evaluating his flight state. Background Art

[0002] With the continuous improvement of the maneuverability of new aircraft and the substantial increase in the level of aircraft informatization, pilots not only have to face a complex acceleration environment, but also have to face enormous information pressure and mental workload. These problems have greatly increased the difficulty of diagnosing the pilot's flight status and the complexity of the commander's medical diagnosis and decision-making based on the flight status assessment. These situations may lead to the failure of the flight mission at the least, or even a flight accident at the worst.

[0003] Specifically, in recent years, the training level and intensity of pilots in my country have been greatly improved. Night low-visibility training, low-altitude raids at sea, long-flight training, and complex weather flight training have become the norm. These high-difficulty, high-load flights generally require pilots to maintain good attention and alertness for a long time, and to ensure that they can maintain a good psychological state and cognitive level. In addition, the acceleration of multiple axes at the same time may also cause serious flight illusions (also known as spatial orientation disorders) for pilots, which brings severe challenges to pilots. When performing flight missions, even if the pilots are extremely tired or disabled in the air, the commanders, decision makers, aviation doctors, etc. at the tower or command center cannot understand the pilots' physiological state in real time, let alone adjust the flight mission in real time according to the situation.

[0004] Since monitoring the physiological state of pilots has important application value for flight safety and the completion of flight missions, some air force powers have begun monitoring the physiological state of pilots since at least the 1960s. However, due to the limitations of the monitoring technology and hardware conditions at the time, this type of monitoring was still relatively primitive and had not been applied on a large scale.

[0005] The rise of wearable devices in recent years has made it easier to monitor physiological status during flight. For example, chest straps, ECG stickers, and dynamic electrocardiographs can be used to collect pilots' electrocardiograms in the air. , Electrocardiography), and then based on Calculate the heart rate ( , Heart Rate, unit is ), heart rate variability ( , Heart Rate Variability) and other indicators are used to evaluate the state of the pilot's individual autonomic nervous system. Dry electrodes or wet electrodes are used on the head to measure EEG ( ) status, which can be used to evaluate indicators such as pilot fatigue status.

[0006] Photoplethysmography ( Photoplethysmography is another non-invasive photoelectric measurement technique. The signal measurement equipment contains at least one infrared transmitter and one receiver (or multiple receivers), which can detect the relative blood volume changes in peripheral tissue blood vessels. The principle is to illuminate the skin of a specified part with light of a specific wavelength, and then receive the transmitted light or reflected light by the transmission or reflection principle. Due to the absorption and attenuation of the skin, muscles and blood, the light intensity monitored by the receiver will attenuate, and then important physiological information of the cardiovascular system such as cardiac function and blood flow will be obtained through specific algorithms. This technology has the advantages of being non-invasive, easy to operate, and having stable measurement results. Based on the above principle, the blood volume pulse wave can be obtained through a specific algorithm. signal, and then get and According to existing research, and Obtained Features are highly correlated. Expected to replace conduct In addition, the above method can be used to calculate and Understand the pilot's heart status and blood perfusion.

[0007] Based on the above principle, some powerful air force countries have developed a variety of portable bio-signal monitoring devices, which can generally collect pilots' electrocardiogram, breathing and other physiological data in real time, and then help aviation doctors understand the pilots' physiological status in real time. However, this type of equipment has never been used on a large scale for many reasons, mainly the following aspects.

[0008] First, the monitoring equipment is inconvenient to wear, which seriously affects the pilot's operation and comfort. Since pilots have to wear anti-gravity suits, flight helmets and other flight equipment, the collection of ECG and EEG data is limited. These collection devices interfere with the flight equipment, and pilots are likely to experience electrode detachment and electrode position movement during intense driving operations. In addition, flight equipment is generally multi-lead wired electrodes that need to be tightly adhered to the skin surface. After sweating, itching and stinging will occur, and tearing them off will cause skin damage, which makes pilots very disgusted. Too many signal lines may even affect the pilot's operation, and in extreme cases, it may affect the pilot's ejection.

[0009] Second, the monitoring equipment signal is too affected by the pilot's movement, resulting in too much signal noise and cannot be used to evaluate the pilot's flight status. Existing acquisition devices will generate a lot of artifacts as long as the head moves, and wristwatch-type measurement devices are greatly affected by hand movements, resulting in poor measurement data accuracy. Pilots have to perform complex flight operations in actual flight and quickly turn their heads to observe the target. During rapid maneuvering flight, pilots are also affected by three-dimensional acceleration fields and severe vibrations. These factors make it impossible for physiological equipment monitoring devices to accurately collect human physiological status signals, which seriously limits the development of pilot physiological monitoring technology;

[0010] Third, the existing physiological detection / monitoring equipment for pilots generally only focuses on the health status of pilots, and simply moves the ground monitoring equipment to the air. These devices have little guiding significance for flight, and cannot provide effective information for flight missions. Specifically, the existing wearable physiological detection / monitoring equipment is generally a modification of commonly used consumer-grade health monitoring equipment. Generally, it can only simply monitor indicators such as breathing, blood oxygen, heart rate, and body temperature. These indicators can be used to evaluate physiological conditions such as sleep status, exercise intensity, and tension, but they are not combined with air flight. It is impossible to objectively evaluate the pilot's fatigue level during long-distance flight, the pilot's cerebral ischemia under high load, and the pilot's ability to resist psychological shock when performing flight missions. In general, it can neither provide guarantee for flight safety nor help the completion of flight missions. Therefore, this technology has not been valued and widely used. Summary of the invention

[0011] In view of the above analysis, an embodiment of the present invention aims to provide a method for monitoring a pilot's physiological state in the air and evaluating the flight state, so as to solve the technical problems that existing pilot physiological monitoring equipment is inconvenient to wear, the signal is greatly disturbed by motion, and is not closely integrated with the flight mission, which limits the application of physiological monitoring equipment in flight safety and mission evaluation.

[0012] The present invention provides a method for monitoring a pilot's physiological state in the air and evaluating the flight state, comprising the following steps:

[0013] Predetermine the regional brain oxygen saturation of the pilot to be evaluated Baseline value;

[0014] During flight, the pilot's blood volume pulse wave is monitored Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data;

[0015] Based on the regional cerebral oxygen saturation Baseline value, regional cerebral oxygen saturation Real-time calculation of physiological status data in the air The offset ratio ;

[0016] Based on the offset ratio and six-axis acceleration signal data, respectively, to monitor the pilot in real time Risk Warning and Coriolis Illusion Risk Warning;

[0017] Based on the blood volume pulse wave The pilot's real-time heart rate obtained from the signal , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment result in real time.

[0018] Further, based on the offset ratio Real-time monitoring of the pilot Risk warning; among them,

[0019] when The output result is "good oxygen supply";

[0020] when The output result is "mild hypoxia";

[0021] when The output result is "moderate hypoxia, pay close attention";

[0022] when The output result is "Severe hypoxia, take action";

[0023] in, is the default value.

[0024] Furthermore, the six-axis acceleration signal data includes the rotational acceleration of the three rotation axes X, Y, and Z and the linear accelerations in the three axes ;

[0025] When the rotational acceleration When any two or three of the above are simultaneously greater than a preset threshold, it is determined that the pilot is at risk of Coriolis illusion.

[0026] Furthermore, the pilot's flight status assessment results include flight proficiency, flight tension, flight fatigue, flight stability, flight training intensity and flight training difficulty assessment results.

[0027] Further, based on the pilot's real-time heart rate , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment results in real time, including:

[0028] Based on the real-time heart rate , obtain the average, maximum and minimum heart rate values ​​of the pilot from the start of takeoff to the current moment, and calculate the pilot's flight proficiency in real time;

[0029] Based on the maximum and average heart rate values ​​at the current moment, the pilot's flight stress level is calculated in real time;

[0030] Based on the offset ratio Make segmented judgments and obtain the pilot's flight fatigue in real time;

[0031] Based on the maximum and minimum heart rate values ​​at the current moment, the pilot's flight stability is calculated in real time;

[0032] Based on the monitored linear acceleration , calculate the aircraft load value, and then obtain the maximum and minimum load values ​​of the aircraft from the beginning of takeoff to the current moment;

[0033] Based on the maximum load value of the aircraft at the current moment, the pilot's flight training intensity is calculated in real time;

[0034] Based on the maximum and minimum load values ​​of the aircraft at the current moment, the pilot's flight training difficulty is calculated in real time.

[0035] Furthermore, a radar chart is used to output and display the pilot's flight status evaluation result in real time; wherein the radar chart includes six axes, each axis represents a dimension, and the data points on the axis are the pilot's performance level in the dimension;

[0036] Each axis of the radar chart has a preset corresponding threshold value, which is used as a benchmark threshold value of six dimensions for each pilot during the flight process for evaluation and intuitive display.

[0037] Furthermore, the pilot's flight proficiency is calculated as follows:

[0038] ;

[0039] in, For pilots’ flying proficiency; and It is divided into the pilot's average heart rate during flight, and the maximum and minimum heart rate at the current moment;

[0040] The pilot's flight stress is calculated as follows:

[0041] ;

[0042] in, The flight tension of the pilots;

[0043] The pilot's flight fatigue is calculated as follows:

[0044] ;

[0045] in, It is the pilot's flight fatigue.

[0046] Furthermore, the pilot's flight stability is calculated as follows:

[0047] ;

[0048] in, Flight stability for the pilot;

[0049] The flight training intensity of the pilot is calculated as follows:

[0050] ;

[0051] in, The intensity of flight training for pilots, is the maximum load value of the aircraft at the current moment;

[0052] The pilot's flight training difficulty is calculated as follows:

[0053] ;

[0054] in, The difficulty of flight training for pilots, It is the minimum load value of the aircraft at the current moment.

[0055] Furthermore, the local brain oxygen saturation of the pilot to be evaluated is predetermined Benchmark values ​​include:

[0056] Before the flight begins, measure The pilot's regional brain oxygen saturation is to be assessed in minutes Physiological status data, obtained Within minutes The continuous change data is averaged to obtain the local cerebral oxygen saturation Benchmark value ;in, is the default value.

[0057] Further, based on the monitored blood volume pulse wave Signal, measurement The interval between the P peaks of the signal, get the time interval between the P peaks , based on the Calculate the pilot's real-time heart rate ,as follows:

[0058] ;

[0059] Based on the linear acceleration , calculate aircraft load values ​​in real time ,as follows:

[0060] ;

[0061] in, is the acceleration due to gravity.

[0062] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0063] 1. The present invention monitors the pilot's blood volume pulse wave during flight Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data are used to monitor the pilot in real time. Risk warning and Coriolis illusion risk warning solve the problem that the existing pilot physiological status monitoring signal is greatly disturbed by movement and cannot provide real-time risk warning, thus ensuring safe flight for pilots;

[0064] 2. The present invention can measure the pilot's local brain oxygen saturation Real-time monitoring of the pilot's blood oxygen level is then divided into four states: good oxygen supply, mild hypoxia, moderate hypoxia (close attention should be paid), and severe hypoxia (action should be taken). When a heavy load flight occurs, the blood moves downward rapidly under the action of gravity, resulting in insufficient oxygen supply to the brain, which may induce black vision or gray vision and seriously affect flight safety. The method of the present invention can effectively monitor the brain oxygen supply level. When moderate or severe hypoxia occurs, a real-time risk warning is issued, and the commander intervenes in time to avoid flight accidents caused by it.

[0065] 3. The six-axis acceleration signal data monitored in real time by the present invention is as long as any two or three of the rotational accelerations are greater than , determine that the pilot is at risk of Coriolis illusion, output "Coriolis illusion has occurred" warning information, and realize real-time warning of Coriolis illusion. This method is relatively simple and easy to implement. It directly measures the acceleration of head rotation to determine whether Coriolis illusion has occurred, without paying attention to the human body's own feelings at this time. This avoids the complicated judgment process, and provides real-time warning of Coriolis illusion risk, which reduces the difficulty of warning and improves flight safety.

[0066] 4. The physiological status measurement results are closely related to the flight status, but most of the previous physiological monitoring equipment only focused on the physiological status, and it is difficult to provide information on the pilot's flight level. This leads to the decoupling of physiological status monitoring from flight ability judgment, which seriously hinders the practical application of physiological monitoring during flight. The present invention designs a six-dimensional flight status assessment method, which assesses the pilot's mastery of training subjects through flight proficiency; judges the pilot's tension during flight through flight tension; judges the pilot's brain fatigue level at this time through flight fatigue; judges the pilot's stability during flight through flight stability; judges whether the flight training can reach the predetermined intensity through flight training intensity; and judges whether the flight process can reach the predetermined difficulty level through flight training difficulty. The six indicators are output and displayed in real time in a comprehensive and intuitive manner through radar charts, so that commanders can fully understand the pilot's physiological data and grasp the pilot's flight status, training effect and task completion level;

[0067] 5. The pilot's physiological status data monitored by the present invention is mainly blood volume pulse wave Signal, regional cerebral oxygen saturation These physiological status data are less affected by the acceleration and vibration of the aircraft. Since the monitoring part is on the forehead and not on the arm, the pilot's operation process will not affect the physiological status data, thus achieving accurate assessment of the pilot's flight status.

[0068] 6. Real-time Risk warning and Coriolis illusion risk warning, as well as real-time pilot flight status assessment results, make it convenient for commanders to adjust flight missions in real time according to the pilot's physical condition and force the aircraft to change operations, which is conducive to preventing flight accidents and improving the efficiency of flight mission training.

[0069] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. In the entire drawings, the same reference symbols represent the same components;

[0071] Figure 1 This is a flow chart of a method for monitoring a pilot's physiological state in the air and evaluating his flight state in an embodiment of the present invention;

[0072] Figure 2This is a schematic diagram of the overall structure of the monitoring device in an embodiment of the present invention;

[0073] Figure 3 The outer shape and inner structure of the headband type physiological monitoring module in the embodiment of the present invention;

[0074] Figure 4 is a schematic diagram of six-axis acceleration of a pilot's head in an embodiment of the present invention;

[0075] Figure 5 This is an example diagram of using a six-dimensional radar chart to output and display a six-dimensional flight level assessment result in an embodiment of the present invention. DETAILED DESCRIPTION

[0076] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0077] During the flight, the pilot's head swings slightly and the forehead is more convenient to measure. Therefore, the forehead is used in the present invention. Signal monitoring has certain convenience advantages. The headband physiological monitoring module is based on Signal to get real-time heart rate It helps to collect heart signals to monitor changes in alertness levels, and existing studies have shown that heart rate The change in can be used as a potential predictor of fatigue onset, indicating that headband sensors can be used to monitor changes in workload or stress during flight training or flight missions. It can be used to accelerate the training of flight trainees, and when flight fatigue is more serious, training can be suspended, thereby reducing training costs and continuous psychological and physiological stress on pilots. It can also help commanders understand the fatigue status of pilots during flight missions, conduct real-time diagnosis and decision-making, and reasonably adjust and allocate task intensity to make flight missions more efficient.

[0078] In addition, since oxygenated hemoglobin and deoxygenated hemoglobin in the blood have different absorption spectra in the red light and near-infrared light regions, The signal has also become a simple and effective method to study blood oxygen status. Signal measurement can be obtained by synchronization (regional cerebral oxygen saturation) The measurement is about the change of local cerebral blood oxygen in the frontal cortex brain tissue, which reflects the balance of brain tissue oxygen supply. Compared with measuring arterial blood oxygen saturation at the fingernails, it can better reflect the pilot's brain hypoxia and reflect the changes in the pilot's brain cognitive function. In addition, when flying for a long time, the pilot's brain will slowly become hypoxic, causing decline.

[0079] A specific embodiment of the present invention discloses a method for monitoring the physiological state of a pilot in the air and evaluating the flight state, such as Figure 1 As shown, the following steps are included:

[0080] Step S1: Predetermine the local brain oxygen saturation of the pilot to be evaluated Baseline value;

[0081] Step S2: During the flight, monitor the pilot's blood volume pulse wave Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data;

[0082] Based on the regional cerebral oxygen saturation Baseline value, regional cerebral oxygen saturation Real-time calculation of physiological status data in the air The offset ratio ;

[0083] Step S3: Based on the offset ratio and six-axis acceleration signal data, respectively, to monitor the pilot in real time Risk Warning and Coriolis Illusion Risk Warning;

[0084] Based on the blood volume pulse wave The pilot's real-time heart rate obtained from the signal , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment result in real time.

[0085] like Figure 2 As shown, the overall structure of the monitoring equipment used in the present invention is composed of a tower command module, an onboard receiving and transmitting module, a headband physiological monitoring module, and a data link between the aircraft and the tower command module;

[0086] The headband physiological monitoring module has a built-in six-axis acceleration sensor, a blood oxygen pulse wave sensor (including a near-infrared blood oxygen transmitter module and two near-infrared blood oxygen receiver modules), a battery, a main board, a signal processing chip, a Bluetooth transmission chip, and quick-release buckle structures on both sides. Figure 3 Schematic diagram of the outside and inside of the headband shown.

[0087] The headband physiological monitoring module is worn on the pilot's forehead and is fixed by a moderately tight elastic headband connected to the quick-release buckles on both sides. It can monitor the pilot's blood volume and pulse wave in real time. Signal, regional cerebral oxygen saturation , six-axis acceleration signal;

[0088] Figure 3 The signal processing chip and Bluetooth transmission chip in it are the onboard receiving and transmitting modules; the signal processing chip is responsible for processing and analyzing the physiological data collected by the sensor; the Bluetooth transmission chip receives the data sent by the headband physiological monitoring module in real time, and transmits the data to the data link sending device on the aircraft, and sends the data to the tower command module built into the airport tower computer through the data link.

[0089] The tower command module calculates the monitoring data in real time according to the preset algorithm to obtain the pilot's physiological state and the completion of the flight mission, and then understands the pilot's real-time physiological state and flight mission execution status in the air. When there is a risk warning or a dangerous situation such as the Coriolis illusion risk warning, the commander can respond quickly based on the pilot's physiological status data and risk warning situation, and it can also help the commander make flight mission decisions and adjust the flight mission in a timely manner.

[0090] The blood oxygen pulse wave sensor includes a blood oxygen transmitting module and two blood oxygen receiving modules; the transmitter of the blood oxygen transmitting module transmits near-infrared light of a specific frequency, and the receivers of the two blood oxygen receiving modules respectively receive the near-infrared light reflected back by the human cerebral cortex tissue. The receiver of the blood oxygen receiving module closer to the blood oxygen transmitting module reversely infers the change in the intensity of the received near-infrared light to obtain the blood volume pulse wave Signal;

[0091] The receiver of the blood oxygen receiving module that is farther away from the blood oxygen transmitting module can subtract the near-infrared light intensity it receives from the near-infrared light intensity received by the receiver that is closer to the transmitting module, and then use a specific algorithm to obtain the blood oxygen situation in the cerebral cortex, that is, the local brain oxygen saturation. .

[0092] The six-axis acceleration sensor monitors the six-axis acceleration signal data of the three rotation axes of X, Y, and Z, including the rotation acceleration of the three axes and the linear accelerations in the three axes ;like Figure 4 shown.

[0093] The batteries are placed between the two blood oxygen receiving modules to power each module in the headband physiological monitoring module;

[0094] The mainboard's built-in Bluetooth transmission chip and signal processing chip are mainly used for data analysis, processing and transmission.

[0095] The headband-type physiological monitoring module has quick-release buckles on both sides for easy disassembly and assembly. Pilots can easily install the monitoring module on the headband, or quickly and conveniently remove it when monitoring is not needed. The elastic strap can be quickly replaced.

[0096] Different pilots have different head circumferences and require different headband sizes or styles. The quick-release buckle allows pilots to easily replace the headband according to their needs.

[0097] Step S1: predetermining the local brain oxygen saturation of the pilot to be evaluated Benchmark values ​​include:

[0098] Before the flight begins, measure The pilot's regional brain oxygen saturation is to be assessed in minutes Physiological status data, obtained Within minutes The continuous change data is averaged to obtain the local cerebral oxygen saturation Benchmark value ;in, is the default value.

[0099] For example, The timer is 5 minutes. It can be set according to the specific needs of the actual flight mission.

[0100] Step S2 is divided into steps S21-S23, specifically.

[0101] Step S21: During the flight, monitor the pilot's blood volume pulse wave Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data;

[0102] The receiver of the blood oxygen receiving module closer to the blood oxygen transmitting module obtains the blood volume pulse wave through the change of the received near-infrared light intensity. Signal;

[0103] The receiver of the blood oxygen receiving module farther away from the blood oxygen transmitting module subtracts the near-infrared light intensity received by the receiver closer to the transmitting module from the near-infrared light intensity it receives to obtain the blood oxygen situation in the cerebral cortex, that is, the local brain oxygen saturation. ;

[0104] The six-axis acceleration sensor receives six-axis acceleration signal data in real time. The six-axis acceleration signal data includes the rotational acceleration of the three rotation axes X, Y, and Z. and the linear accelerations in the three axes .

[0105] Step S22: based on the local brain oxygen saturation Benchmark value , regional cerebral oxygen saturation Real-time calculation of physiological status data in the air The offset ratio ;

[0106] Regional cerebral oxygen saturation It is the change of local cerebral blood oxygen in the frontal cortex brain tissue, reflecting the balance of brain tissue oxygen supply. It can directly and continuously monitor the brain hypoxia non-invasively. Compared with measuring arterial blood oxygen saturation at the fingernails, it can better reflect the pilot's brain hypoxia state and reflect the changes in brain cognitive function. In addition, when the pilot's body is loaded towards the head and feet during flight, the pilot's blood will gather towards the lower limbs under the action of the load, causing severe ischemia and hypoxia in the head, which is manifested as a decline in cognitive function, and in severe cases, it will lead to black or gray vision.

[0107] Based on the regional cerebral oxygen saturation Baseline value, regional cerebral oxygen saturation Real-time calculation of physiological status data in the air The offset ratio , as shown in formula (1):

[0108] ;

[0109] in, For real-time monitoring of pilots .

[0110] Step S3, including steps S31-S34, specifically.

[0111] Step S31: based on the local brain oxygen saturation Baseline values, monitored regional cerebral oxygen saturation In-flight physiological status data, real-time monitoring of pilots Risk warning.

[0112] Based on the offset ratio Real-time monitoring of the pilot Risk warning; among them,

[0113] when The output result is "good oxygen supply";

[0114] when The output result is "mild hypoxia";

[0115] when The output result is "moderate hypoxia, pay close attention";

[0116] when The output result is "Severe hypoxia, take action";

[0117] in, is the default value.

[0118] Default Value Set according to specific flight requirements; for example, , the output is as follows:

[0119] when The output result is "good oxygen supply";

[0120] when The output result is "mild hypoxia";

[0121] when The output result is "moderate hypoxia, pay close attention";

[0122] when The output result is "Severe hypoxia, action is required".

[0123] The above method can help the commander understand the pilot's cerebral cortex hypoxia state.

[0124] When "serious hypoxia, action is required", the commander can decisively take measures such as automatic leveling and forced oxygen supply according to the flight mission to avoid flight accidents;

[0125] In the case of "moderate hypoxia, pay close attention", the local brain oxygen saturation Determine the level of hypoxia, understand the pilot's fatigue state and brain excitement level, and assign further flight tasks based on the pilot's level of alertness.

[0126] Regional cerebral oxygen saturation deviation ratio The division method here is and , can be reset by the commander according to the specific needs of the flight mission, so when performing certain heavy load or long-term flight missions, the pilot who monitors in real time The value can become lower than normal flight missions.

[0127] Step S32: Based on the six-axis acceleration signal data, a Coriolis illusion risk warning is provided to the pilot in real time.

[0128] During flight, when the aircraft rotates around an axis (such as circling, rolling and spiraling), if the pilot's head also rotates at the same time, or when the aircraft rotates around two or three axes at the same time (such as when performing stunts such as half somersaults), the pilot's head will experience a special acceleration, called "Coriolis acceleration". The complex feeling of flipping, rolling or rotating felt by the pilot when subjected to this acceleration is called the Coriolis illusion. After the Coriolis illusion occurs, symptoms such as dizziness, sweating, pale complexion, nausea and vomiting will appear one after another depending on the severity, and even syncope may occur, which seriously affects flight safety.

[0129] Coriolis illusion warning has always been a difficult problem in illusion warning. The reason is that Coriolis illusion is caused by the movement of the pilot's head and the movement of the aircraft. It is impossible to issue a warning based on the flight parameters (i.e., the acceleration of the aircraft) alone. The six-axis acceleration sensor of the present invention measures the six-axis acceleration of the head, such as Figure 4 As shown, both head movement and aircraft movement can be effectively measured, and because the measurement is made on the head, it is closer to the acceleration of the semicircular canals in the vestibular system, thus ensuring that the measured six-axis acceleration signal data is closer to the acceleration perceived by the human body.

[0130] When the rotational acceleration When any two or three of the above are simultaneously greater than a preset threshold, it is determined that the pilot is at risk of Coriolis illusion.

[0131] Exemplarily, the preset threshold is .

[0132] in is the unit of angular acceleration, If any one of them rotates, the pilot will not experience the Coriolis illusion. If any two of them rotate at the same time, or if all three rotate at the same time, the pilot will not experience the Coriolis illusion. When the pilot is flying, he experiences the Coriolis delusion.

[0133] Regardless of whether the pilot suffers from severe dizziness at this time, the risk warning information of "Coriolis illusion has occurred" is immediately and directly output; at this time, the command tower will directly take the approach of leveling off or issue an order to terminate the flight mission based on the flight mission situation and the local blood oxygen saturation level in the brain.

[0134] Step S33: based on the pilot's real-time heart rate , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment result in real time.

[0135] The pilot's flight status assessment results include flight proficiency, flight tension, flight fatigue, flight stability, flight training intensity and flight training difficulty assessment results.

[0136] In order to conduct a systematic evaluation of the completion of the flight mission, the collected Signal data and linear acceleration Perform analysis and calculation to obtain real-time heart rate and aircraft load values.

[0137] Based on the blood volume pulse wave monitored Signal, measurement The interval between the P peaks of the signal is obtained, and the time interval between the P peaks (PP interval, in seconds) is obtained based on the Calculate the pilot's real-time heart rate , as shown in formula (2):

[0138] ;

[0139] Based on the linear acceleration , calculate aircraft load values ​​in real time , as shown in formula (3):

[0140] ;

[0141] in, is the acceleration due to gravity.

[0142] The linear acceleration of three axes is measured by the six-axis motion sensor, and the results are: , the units are .in, is the acceleration along the longitudinal axis of the human body, which has the greatest impact on the human body. , convert it into aircraft load value , the unit is , for example , or take , determined according to the specific accuracy required. Aircraft load value It means that the value of gravity acceleration to which the pilot is subjected is several times greater than that of a normal human body standing on the ground. The maximum value of , the minimum value is recorded as .

[0143] Based on the pilot's real-time heart rate , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment results in real time, including:

[0144] Based on the real-time heart rate , obtain the average, maximum and minimum heart rate values ​​of the pilot from the start of takeoff to the current moment, and calculate the pilot's flight proficiency in real time;

[0145] Based on the maximum and average heart rate values ​​at the current moment, the pilot's flight stress level is calculated in real time;

[0146] Based on the offset ratio Make segmented judgments and obtain the pilot's flight fatigue in real time;

[0147] Based on the maximum and minimum heart rate values ​​at the current moment, the pilot's flight stability is calculated in real time;

[0148] Based on the monitored linear acceleration , calculate the aircraft load value, and then obtain the maximum and minimum load values ​​of the aircraft from the beginning of takeoff to the current moment;

[0149] Based on the maximum load value of the aircraft at the current moment, the pilot's flight training intensity is calculated in real time;

[0150] Based on the maximum and minimum load values ​​of the aircraft at the current moment, the pilot's flight training difficulty is calculated in real time.

[0151] The pilot's flight evaluation results, flight proficiency, flight stress, flight fatigue, flight stability, flight training intensity and flight training difficulty are calculated as follows:

[0152] (1) Pilot’s flying proficiency ( ), reflects the pilot's familiarity with flight maneuvers during the flight, and uses the average heart rate indicator to reflect the pilot's energy consumption during the flight. The larger the flight proficiency value, the more proficient the pilot is in the training subjects and the more stable his mentality.

[0153] The pilot's flight proficiency is calculated as shown in formula (4):

[0154] ;

[0155] in, For pilots’ flying proficiency; and It is divided into the pilot's average heart rate during flight, and the maximum and minimum heart rate at the current moment;

[0156] (2) Flight stress ), reflects the pilot's tension during the entire flight process, and uses the maximum heart rate indicator to reflect the pilot's psychological changes during the flight. The larger the value, the more relaxed the pilot is during the flight, and the smaller the value, the more nervous the pilot is.

[0157] The pilot's flight stress is calculated as shown in formula (5):

[0158] ;

[0159] in, The flight tension of the pilots;

[0160] (3) Flight fatigue ), reflects the pilot's fatigue level during the entire flight. The change in the size of the indicator reflects the degree of brain nerve activity during the entire flight, and indirectly reflects the degree of fatigue during the flight. The larger the value, the more likely the pilot is to The lower the value, the more tired the pilot is, and the higher the value, the more relaxed the pilot is after completing the mission.

[0161] The pilot's flight fatigue is calculated as shown in formula (6):

[0162] ;

[0163] in, It is the pilot's flight fatigue.

[0164] (4) Flight stability ( ), reflects the pilot's stability during the entire flight. The heart rate difference during the flight is used to calculate the heart rate changes during the flight to reflect the flight stability. The larger the value, the more stable the flight.

[0165] The pilot's flight stability is calculated as shown in formula (7):

[0166] ;

[0167] in, Flight stability for the pilot;

[0168] (5) Flight training intensity ( ), reflects the intensity of the entire flight process, and uses the maximum overload to calculate the training intensity during the flight. The larger the value, the greater the intensity of the flight training.

[0169] The pilot's flight training intensity is calculated as shown in formula (8):

[0170] ;

[0171] in, The intensity of flight training for pilots, is the maximum load value of the aircraft at the current moment;

[0172] (6) Flight training difficulty ( ), reflects the difficulty of the entire flight process. The training difficulty during the flight is calculated with the help of the overload difference during the flight. The larger the value, the greater the difficulty of the training.

[0173] The pilot's flight training difficulty is calculated as shown in formula (9):

[0174] ;

[0175] in, The difficulty of flight training for pilots, It is the minimum load value of the aircraft at the current moment.

[0176] Step S34: output and display the pilot's six-dimensional flight mission evaluation result using a radar chart.

[0177] like Figure 5 As shown, a radar chart is used to output and display the flight status evaluation result of the pilot in real time; wherein the radar chart includes six axes, each axis represents a dimension, and the data points on the axis are the performance level of the pilot in the dimension;

[0178] Each axis of the radar chart has a preset corresponding threshold value, which is used as a benchmark threshold value of six dimensions for each pilot during the flight process for evaluation and intuitive display.

[0179] Before using the radar chart, pre-set the upper and lower limits of each dimension. The maximum value of the dimension on the corresponding axis in the radar chart is the upper limit, and the minimum value is the lower limit. If the value of the dimension is lower than the lower limit or higher than the upper limit, the output remains at the lower limit or upper limit. When the value of the dimension changes between the upper and lower limits, the output of the dimension moves on the corresponding dimension axis in the radar chart.

[0180] For example,

[0181] The upper and lower limits of flight proficiency are 1 and 0 by default;

[0182] The default upper and lower limits of flight tension are 1 and 0.5;

[0183] The default upper and lower limits of flight fatigue are 20 and 0;

[0184] The default upper and lower limits of flight stability are 4 and 0;

[0185] The default upper and lower limits of flight training intensity are 1 and 0.1;

[0186] The default upper and lower limits of flight training difficulty are 2 and 0.

[0187] The upper and lower limit values ​​are the default values ​​of the system and are preset values;

[0188] Fine-tune according to the actual needs of flight training and the pilot's physical condition (the upper limit shall not exceed 2 times the default upper limit, and the lower limit shall not be less than 0).

[0189] The results of the pilot's flight status assessment provide a real-time and comprehensive understanding of the pilot's flight performance and mission completion from six dimensions. Among them, flight proficiency, flight stress, flight fatigue, and flight stability are used to evaluate the pilot's performance in flight and the degree of mastery of flight technology. If the value in one dimension is low, subsequent targeted training can be carried out; flight training intensity and flight training difficulty are used to evaluate whether the design of the flight mission is reasonable and whether the pilot has properly implemented the flight mission as planned. If the value is low, it means that the difficulty and intensity of the flight training mission should be adjusted.

[0190] The six-dimensional radar chart is used to output and display the pilot's six-dimensional flight mission evaluation results, which are output and displayed in real time. At the end of the flight, the displayed radar chart is the six-dimensional pilot flight status evaluation result of the entire flight training process.

[0191] The above six dimensions are the six aspects of the pilot's flight status that commanders are most concerned about. Therefore, this radar chart allows commanders to understand which aspects of the pilot's flight status have shortcomings and which aspects perform better through just this one chart, which is conducive to the commander's subsequent more effective training tasks for the pilot.

[0192] In summary, the method for monitoring the physiological state of a pilot in the air and evaluating the flight state according to the embodiment of the present invention has the following beneficial effects:

[0193] 1. The present invention monitors the pilot's blood volume pulse wave during flight Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data are used to monitor the pilot in real time. Risk warning and Coriolis illusion risk warning solve the problem that the existing pilot physiological status monitoring signal is greatly disturbed by movement and cannot provide real-time risk warning, thus ensuring safe flight for pilots;

[0194] 2. The present invention can measure the pilot's local brain oxygen saturation Real-time monitoring of the pilot's blood oxygen level is then divided into four states: good oxygen supply, mild hypoxia, moderate hypoxia (close attention should be paid), and severe hypoxia (action should be taken). When a heavy load flight occurs, the blood moves downward rapidly under the action of gravity, resulting in insufficient oxygen supply to the brain, which may induce black vision or gray vision and seriously affect flight safety. The method of the present invention can effectively monitor the brain oxygen supply level. When moderate or severe hypoxia occurs, a real-time risk warning is issued, and the commander intervenes in time to avoid flight accidents caused by it.

[0195] 3. The six-axis acceleration signal data monitored in real time by the present invention is as long as any two or three of the rotational accelerations are greater than , determine that the pilot is at risk of Coriolis illusion, output "Coriolis illusion has occurred" warning information, and realize real-time warning of Coriolis illusion. This method is relatively simple and easy to implement. It directly measures the acceleration of head rotation to determine whether Coriolis illusion has occurred, without paying attention to the human body's own feelings at this time. This avoids the complicated judgment process, and provides real-time warning of Coriolis illusion risk, which reduces the difficulty of warning and improves flight safety.

[0196] 4. The physiological status measurement results are closely related to the flight status, but most of the previous physiological monitoring equipment only focused on the physiological status, and it is difficult to provide information on the pilot's flight level. This leads to the decoupling of physiological status monitoring from flight ability judgment, which seriously hinders the practical application of physiological monitoring during flight. The present invention designs a six-dimensional flight status assessment method, which assesses the pilot's mastery of training subjects through flight proficiency; judges the pilot's tension during flight through flight tension; judges the pilot's brain fatigue level at this time through flight fatigue; judges the pilot's stability during flight through flight stability; judges whether the flight training can reach the predetermined intensity through flight training intensity; and judges whether the flight process can reach the predetermined difficulty level through flight training difficulty. The six indicators are output and displayed in real time in a comprehensive and intuitive manner through radar charts, so that commanders can fully understand the pilot's physiological data and grasp the pilot's flight status, training effect and task completion level;

[0197] 5. The pilot's physiological status data monitored by the present invention is mainly blood volume pulse wave Signal, regional cerebral oxygen saturation These physiological status data are less affected by the acceleration and vibration of the aircraft. Since the monitoring part is on the forehead and not on the arm, the pilot's operation process will not affect the physiological status data, thus achieving accurate assessment of the pilot's flight status.

[0198] 6. Real-time Risk warning and Coriolis illusion risk warning, as well as real-time pilot flight status assessment results, make it convenient for commanders to adjust flight missions in real time according to the pilot's physical condition and force the aircraft to change operations, which is conducive to preventing flight accidents and improving the efficiency of flight mission training.

[0199] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for monitoring a pilot's physiological state in the air and evaluating his flight state, characterized in that: The steps include: Predetermine the regional brain oxygen saturation of the pilot to be evaluated Baseline value; During flight, the pilot's blood volume pulse wave is monitored Signal, regional cerebral oxygen saturation In-flight physiological status data and six-axis acceleration signal data; Based on the regional cerebral oxygen saturation Baseline value, regional cerebral oxygen saturation Real-time calculation of physiological status data in the air The offset ratio ; Based on the offset ratio and six-axis acceleration signal data, respectively, to monitor the pilot in real time Risk Warning and Coriolis Illusion Risk Warning; Based on the blood volume pulse wave The pilot's real-time heart rate obtained from the signal , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment result in real time; The six-axis acceleration signal data includes the rotational acceleration of the three rotation axes X, Y, and Z. and the linear accelerations in the three axes ; When the rotational acceleration When any two or three of the above are greater than a preset threshold at the same time, it is determined that the pilot is at risk of Coriolis illusion; The preset threshold is ; The pilot's flight status assessment results include flight proficiency, flight tension, flight fatigue, flight stability, flight training intensity and flight training difficulty assessment results; Based on the pilot's real-time heart rate , and the offset ratio and six-axis acceleration signal data to obtain the pilot's flight status assessment results in real time, including: Based on the real-time heart rate , obtain the average, maximum and minimum heart rate values ​​of the pilot from the start of takeoff to the current moment, and calculate the pilot's flight proficiency in real time; Based on the maximum and average heart rate values ​​at the current moment, the pilot's flight stress level is calculated in real time; Based on the offset ratio Make segmented judgments and obtain the pilot's flight fatigue in real time; Based on the maximum and minimum heart rate values ​​at the current moment, the pilot's flight stability is calculated in real time; Based on the monitored linear acceleration , calculate the aircraft load value, and then obtain the maximum and minimum load values ​​of the aircraft from the beginning of takeoff to the current moment; Based on the maximum load value of the aircraft at the current moment, the pilot's flight training intensity is calculated in real time; Based on the maximum and minimum load values ​​of the aircraft at the current moment, the pilot's flight training difficulty is calculated in real time.

2. The method according to claim 1, characterized in that: Based on the offset ratio The pilot is monitored in real time Risk warning; among them, when The output result is "good oxygen supply"; when The output result is "mild hypoxia"; when The output result is "moderate hypoxia, pay close attention"; when The output result is "severe hypoxia, take action"; in, is the default value.

3. The method according to claim 1, characterized in that: The radar chart is used to output and display the flight status evaluation result of the pilot in real time; wherein the radar chart includes six axes, each axis represents a dimension, and the data points on the axis are the performance level of the pilot in the dimension; Each axis of the radar chart has a preset corresponding threshold value, which is used as a benchmark threshold value of six dimensions for each pilot during the flight process for evaluation and intuitive display.

4. The method according to claim 1, characterized in that: The pilot's flying proficiency is calculated as follows: ； in, For pilots’ flying proficiency; and It is divided into the pilot's average heart rate during flight, and the maximum and minimum heart rate at the current moment; The pilot's flight stress is calculated as follows: ； in, The flight tension of the pilots; The pilot's flight fatigue is calculated as follows: ； in, It is the pilot's flight fatigue.

5. The method according to claim 4, characterized in that: The pilot's flight stability is calculated as follows: ； in, Flight stability for the pilot; The flight training intensity of the pilot is calculated as follows: ； in, The intensity of flight training for pilots, is the maximum load value of the aircraft at the current moment; The pilot's flight training difficulty is calculated as follows: ； in, The difficulty of flight training for pilots, It is the minimum load value of the aircraft at the current moment.

6. The method according to claim 1, characterized in that: The local cerebral oxygen saturation of the pilot to be evaluated is predetermined Benchmark values ​​include: Before the flight begins, measure The pilot's regional brain oxygen saturation is to be assessed in minutes Physiological status data, obtained Within minutes The continuous change data is averaged to obtain the local cerebral oxygen saturation Benchmark value ;in, is the default value.

7. The method according to claim 1, characterized in that: Based on the blood volume pulse wave monitored Signal, measurement The interval between the P peaks of the signal, get the time interval between the P peaks , based on the Calculate the pilot's real-time heart rate ,as follows: ； Based on the linear acceleration , calculate aircraft load values ​​in real time ,as follows: ； in, is the acceleration due to gravity.

Images