TWI602143B - Fatigue detection apparatus and a fatigue detection method - Google Patents

Description

Fatigue detecting device and fatigue detecting method

The invention relates to a detecting device and a detecting method, and in particular to a fatigue detecting device and a fatigue detecting method.

Traditionally, there are two main types of techniques commonly used for fatigue detection, namely brain wave analysis and cardiovascular index analysis. In the analysis of brain waves, it is mainly to detect whether there is a sleep wave in the brain wave, and then determine the state of consciousness of the subject. However, due to the large individual differences, the high complexity of brain waves, and the characteristics of being susceptible to noise interference, the reliability of brainwave analysis has not been well applied. On the other hand, in the analysis of cardiovascular indicators, it is mainly to detect a single physiological index related to cardiovascular assessment to assess whether the subject appears to have a sleep state, such as heartbeat slowing, etc., to determine whether the subject has entered fatigue state. . In other words, analyzing the spectrum of the heartbeat can reflect whether the subject's parasympathetic nerve is active, and then determine whether the subject is in a state of fatigue. However, when analyzing the spectrum by such methods, it is easy to cause a distortion of the object to be analyzed in the spectrum due to other variables having similar frequencies (for example, breathing). In addition, once the subject is tired, the heartbeat does not slow down immediately, so the lack of response immediately leads to limitations in its application. As such, how to establish an accurate and more immediate fatigue detecting device and method is still a goal of those skilled in the art.

The invention provides a fatigue detecting device and a fatigue detecting method, which can accurately and instantly determine a change in a user's mental state.

The fatigue detecting device of the present invention comprises a first detecting unit, a second detecting unit and a processing unit. The first detecting unit is configured to obtain the first physiological signal, and the second detecting unit is configured to obtain the second physiological signal. The processing unit is coupled to the first detecting unit and the second detecting unit, and obtains a plurality of characteristic time differences according to the first physiological signal and the second physiological signal, and determines according to the obtained trend of the plurality of characteristic time differences over time. Fatigue detection results.

The fatigue detecting method of the present invention includes the following steps. Get the first physiological signal. Obtain a second physiological signal. A plurality of characteristic time differences are obtained according to the first physiological signal and the second physiological signal. The fatigue detection result is determined according to the trend of the obtained characteristic time difference with time.

Based on the above, the fatigue detecting device and the fatigue detecting method of the present invention use the trend of the plurality of characteristic time differences of the two physiological signals as a basis to determine the fatigue detecting result, and the determining method can be accurate and more accurate. Instantly determine the user's mental state changes, with a wider range of applications.

The above described features and advantages of the invention will be apparent from the following description.

1 is a schematic block diagram of a fatigue detecting device according to an embodiment of the present invention. Referring to FIG. 1 , the fatigue detecting apparatus 100 of the present embodiment includes a first detecting unit 110 , a second detecting unit 130 , and a processing unit 150 . In this embodiment, the first detecting unit is configured to obtain a first physiological signal corresponding to the first physiological indicator, and the second detecting unit is configured to obtain a second physiological signal corresponding to the second physiological indicator. The processing unit 150 is coupled to the first detecting unit 110 and the second detecting unit 130 to calculate a plurality of characteristic time differences according to the first physiological signal and the second physiological signal, and according to the obtained characteristic time difference, changes with time. Trend to determine fatigue detection results.

The first detecting unit 110 and the second detecting unit 130 include, for example, a physiological signal detector for detecting physiological indexes corresponding to blood pressure, body temperature, heart sound, electrocardiogram, pulse wave, respiratory or blood oxygen concentration, etc., to obtain Corresponding physiological signals, the invention is not limited thereto. In this embodiment, the first detecting unit 110 is, for example, an electrocardiogram detector. For example, at least two electrodes can be used to detect potential changes of different parts of the user's body surface to obtain an electrocardiogram as the first physiological signal. Signal. The second detecting unit 130 is, for example, a heart sound detector. For example, the piezoelectric film can be used to detect the heart sound of the user to obtain a heart sound signal as the second physiological signal. However, the present invention does not limit the implementation manner of the first detecting unit 110 and the second detecting unit 130. In other words, those skilled in the art have the ability to adjust the implementation of each of the physiological signal detectors as needed to obtain a corresponding physiological signal.

It is to be noted that, in this embodiment, the first detecting unit 110 and the second detecting unit 130 respectively correspond to different physiological indicators to obtain different types of physiological signals. In another embodiment, the first detecting unit 110 and the second detecting unit 130 may also correspond to the same physiological indicator and obtain the same type of physiological signal. For example, the heart sound signal obtained from different positions of the user's body may correspond to a shock wave emitted by different valves when the user's heart operates. Therefore, the first detecting unit 110 and the second detecting unit 130 can also be, for example, heart sound detectors installed at different positions of the user's body to obtain heart sound signal signals from different valves. The type of physiological signal obtained by a person skilled in the art can determine the type of physiological signal obtained according to the requirements of the present invention, and the present invention is not limited thereto.

The processing unit 150 includes, for example, a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), and a field-programmable gate array (FPGA). The programmable logic device (PLD) or other similar device or a combination of these devices is not limited in the present invention. In this embodiment, the processing unit 150 is coupled to the first detecting unit 110 and the second detecting unit 130, for example, by wire or wirelessly, for acquiring the first physiological signal and the second physiological signal, and according to the first physiological The signal and the second physiological signal are calculated to obtain a plurality of characteristic time differences, and the fatigue detection result is determined according to the trend of the obtained characteristic time difference with time.

In addition, in other embodiments of the present invention, the fatigue detecting device 100 further includes a storage unit and a warning unit. The storage unit is, for example, a hard disk or other form of storage medium, coupled to the processing unit 150 and used to record a plurality of historical information. The historical information includes, for example, various physiological information of a plurality of users in the past, and can reflect different physiological conditions of each user, but the present invention is not limited thereto. In this way, the processing unit 150 can determine the fatigue detection result according to the trend of the characteristic time difference with time and the historical information to respond to the physiological conditions of different users, so as to obtain a more accurate determination result. On the other hand, the warning unit is coupled to the processing unit 150 for issuing a warning signal according to the determined fatigue detection result. The warning unit is, for example, a device that can emit an electrical stimulation signal, an audio signal, a visual signal or other warning signals, and the present invention is not limited thereto.

In one embodiment of the present invention, the fatigue detecting device 100 is mounted on a vehicle as the vehicle fatigue detecting device 100, for example. 2 is a schematic view of a vehicle fatigue detecting device according to an embodiment of the present invention. Referring to FIG. 2, the first detecting unit 110 of the vehicle fatigue detecting apparatus 100 of the present embodiment is, for example, an electrocardiograph, and includes a first electrode 110_1 and a second electrode 110_2 for respectively detecting a user's body. The potentials of the left and right halves are used to obtain a complete electrocardiogram signal as the first physiological signal PS1. The second detecting unit 130 of the vehicle fatigue detecting device 100 is, for example, a heart sound detector, and is mounted on the seat belt SB to accurately obtain the heart sound signal by the characteristics of the seat belt SB close to the human body. The second physiological signal PS2. The processing unit 150 of the vehicle fatigue device 100 is, for example, a buckle attached to a seat belt, a center console of a vehicle, or other position of the vehicle, and the present invention is not limited thereto. In this way, the vehicle fatigue detecting device 100 provided by the embodiment of the present invention can instantly determine the fatigue detecting result of the user when the user drives. In other embodiments, the vehicle fatigue detecting device 100 can promptly alert the user by promptly sending a warning signal to the user to improve the safety of the driving when the fatigue detecting result of the user is determined to be fatigued.

However, the present invention does not limit the installation position or the use range of the fatigue detecting device 100. In other words, the fatigue detecting device 100 of the embodiment of FIG. 1 can also be installed at other locations or used in other contexts according to the needs of the user.

FIG. 3 is a flow chart of a fatigue detecting method according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a fatigue detecting method according to an embodiment of the invention. Referring to FIG. 1 to FIG. 4 simultaneously, the fatigue detecting method of the embodiment is applicable to the fatigue detecting device 100 of the embodiment of FIG. 1 or FIG. The detailed steps of the fatigue detecting method of the present embodiment will be described below with reference to the elements of the fatigue detecting device 100 of FIG.

First, the processing unit 150 of the fatigue detecting device 100 acquires the first physiological signal PS1 from the first detecting unit 110 (step S310), and acquires the second physiological signal PS2 from the second detecting unit 130 (step S320). In this embodiment, the first physiological signal PS1 is, for example, an electrocardiogram signal, and the second physiological signal PS2 is, for example, a heart sound signal. The first detecting unit 110 and the second detecting unit 130 respectively obtain the first physiological signal PS1 and The manner of the second physiological signal PS2 has been described in detail in the embodiment of FIG. 1, and details are not described herein again.

Subsequently, the processing unit 150 acquires a plurality of feature time differences CTD1, CTD2, and CTD3 according to the first physiological signal PS1 and the second physiological signal PS2 (step S330). The characteristic time differences CTD1, CTD2, and CTD3 are, for example, blood pre-ejection period (PEP) times associated with the first physiological signal PS1 and the second physiological signal PS2. In this embodiment, the first physiological signal PS1 is an electrocardiogram signal having a plurality of QRS complexes including a plurality of Q waves Q1 to Q3. The processing unit 150 acquires the occurrence times of the Q waves Q1 to Q3 as the first feature time, respectively (step S331). On the other hand, the second physiological signal PS2 is a heart sound map signal having a plurality of first heart sounds S11 to S13. The processing unit respectively obtains the occurrence times of the first heart sounds S11 to S13 as the second feature time (step S333). After the first feature time and the second feature time are obtained, the processing unit 150 calculates the difference between each of the first feature time and each of the second feature times as the feature time difference (step S335). In detail, in the embodiment, the processing unit 150 calculates the time difference between the Q wave Q1 and the first heart sound S11 as the feature time difference CTD1, and calculates the time difference between the Q wave Q2 and the first heart sound S12 as the characteristic time difference. CTD2, and calculates the time difference between the Q wave Q3 and the first heart sound S13 as the feature time difference CTD3.

After the processing unit 150 obtains a plurality of characteristic time differences, the fatigue detection result may be determined according to the obtained trend of the plurality of characteristic time differences over time (step S340). In this embodiment, the processing unit 150 determines whether the characteristic time differences CTD1, CTD2, and CTD3 change in time with time (step S341), wherein the change trend is consistent to indicate that the change trend is increasing or decreasing. In general, the length of time before the blood output can reflect the blood output of the user's heart, and the longer the blood output period, the less the blood output of the heart. When the blood output of the heart is decreasing, the cerebral blood flow will gradually decrease and the fatigue state will occur. Specifically, in an embodiment of the present invention, the time before the blood output is taken as the characteristic time differences CTD1, CTD2, and CTD3. When the CTD3 is greater than the CTD2 and the CTD2 is greater than the CTD1, it indicates that the time difference of the characteristic time increases with time, which may indicate that the cerebral blood flow of the user is gradually decreased, and the processing unit 150 determines that the fatigue detection result is the fatigue state. (Step S343). Otherwise, the processing unit 150 does not determine that the fatigue detection result is a fatigue state (step S345). In some embodiments, when the processing unit 150 determines that the fatigue detection result is in a fatigue state, the warning unit is further sent a warning signal to remind the user, the manner of which is illustrated in the embodiment of FIG. 1, and details are not described herein again.

It should be noted that, for convenience of description, the number of the first feature time, the second feature time, and the feature time difference in this embodiment is exemplified by three, but the present invention is not limited thereto. In other embodiments, a greater or lesser number of feature time and feature time differences may be obtained as needed to determine the fatigue detection result.

It is worth mentioning that, since the blood output pre-time is taken as the characteristic time difference in the foregoing embodiment, when the characteristic time difference changes with time, the processing unit 150 determines that the fatigue detection result is a fatigue state. However, in other embodiments, the type of the calculated feature time difference will also change based on the type of physiological signal obtained. Therefore, the present invention does not limit the correspondence between the fatigue detection result and the characteristic time difference with time, and the correspondence relationship is determined, for example, depending on the type of the characteristic time difference obtained. In other words, in other embodiments, the processing unit 150 may also determine that the fatigue detection result is a fatigue state because the trend of the time difference of other types of features is decreasing with time.

In particular, in general, the heart rate declines after a period of reduction in cerebral blood flow. Therefore, the fatigue detecting device and the fatigue detecting method provided by the embodiments of the present invention use high-order physiological indexes, and can make fatigue judgment or reminder in real time compared with the conventional technology. On the other hand, since different users may have different physiological conditions, the embodiment of the present invention determines whether the user is in a fatigue state according to whether the characteristic time difference has a consistent trend with time, instead of the absolute value according to the characteristic time difference. To judge. In this way, the fatigue detecting device and the fatigue detecting method provided by the embodiments of the present invention can be adapted to different users, and the fatigue detecting result of the corresponding user is determined to have a wider application.

In addition, in another embodiment of the present invention, the processing unit 150 can determine the fatigue detection result by, for example, matching a plurality of historical information and a trend of the characteristic time difference with time. Historical information, for example, includes various physiological information of a plurality of users in the past, which can reflect the physiological conditions of different users. That is to say, the criterion for determining the fatigue detection result may be determined according to the physiological condition of the user in the past, wherein the determination criterion may be, for example, the number of characteristic time differences having the same change trend, and the like, and the present invention is not limited thereto. In this way, it is more able to adapt to different users and provide more accurate fatigue judgment function.

In summary, the fatigue detecting device and the fatigue detecting method provided by the embodiments of the present invention determine the fatigue detecting result of the user by using the trend of the characteristic time difference with time, and can be adapted to different users. The result of the judgment. In addition, the characteristic time difference is related to the first physiological signal and the second physiological signal, and a higher-order physiological index can be obtained, and the fatigue judgment can be made more instantaneously, thereby having a wider application.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100‧‧‧Fatigue detection device
110‧‧‧First detection unit
110_1‧‧‧First electrode
110_2‧‧‧second electrode
130‧‧‧Second detection unit
150‧‧‧Processing unit
CTD1, CTD2, CTD3‧‧‧ characteristic time difference
PS1‧‧‧First physiological signal
PS2‧‧‧Second physiological signal
Q1, Q2, Q3‧‧‧Q wave

S11, S12, S13‧‧‧ first heart sounds

S310, S320, S330, S331, S333, S335, S340, S341, S343, S345‧‧‧ steps of fatigue detection method

SB‧‧‧Safety belt

1 is a schematic block diagram of a fatigue detecting device according to an embodiment of the present invention. 2 is a schematic view of a vehicle fatigue detecting device according to an embodiment of the present invention. FIG. 3 is a flow chart of a fatigue detecting method according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a fatigue detecting method according to an embodiment of the invention.

S310, S320, S330, S331, S333, S335, S340, S341, S343, S345‧‧‧ steps of fatigue detection method

Claims (17)

A fatigue detecting device includes: a first detecting unit for acquiring a first physiological signal; a second detecting unit for acquiring a second physiological signal; and a processing unit coupled to the first a detecting unit and the second detecting unit, wherein the processing unit obtains a plurality of characteristic time differences according to the first physiological signal and the second physiological signal, and determines a fatigue according to a change trend of the characteristic time differences with time Detect results. The fatigue detecting device of claim 1, wherein the first physiological signal corresponds to a first physiological indicator, the second physiological signal corresponds to a second physiological indicator, and the first physiological indicator is different from the first physiological indicator Two physiological indicators. The fatigue detecting device of claim 1, wherein each of the characteristic time differences is associated with the first physiological signal and the second physiological signal. The fatigue detecting device of claim 1, wherein the processing unit determines that the fatigue detecting result is a fatigue state, wherein the change trend is a fatigue state, wherein the change trend is a fatigue state. To be consistent, the trend is one of increasing or decreasing. The fatigue detecting device of claim 1, further comprising: a storage unit coupled to the processing unit for recording a plurality of historical information, wherein the processing unit is based on the historical information and the change trend Determine the fatigue detection result. For example, the fatigue detecting device described in claim 1 further includes: An alarm unit is coupled to the processing unit for issuing a warning signal according to the fatigue detection result. The fatigue detecting device of claim 2, wherein the first detecting unit is an ECG detector, and the second detecting unit is a heart sound detector. The fatigue detecting device of claim 7, wherein the first physiological signal is an electrocardiogram signal, the second physiological signal is a heart sound signal, and the characteristic time difference is a plurality of blood output pre-pre (pre -ejection period, PEP) time. The fatigue detecting device of claim 1, wherein the fatigue detecting device is adapted to be mounted on a vehicle as a vehicle fatigue detecting device, wherein the first detecting unit and the second detecting unit are at least One of them is mounted on a safety belt of the vehicle. A fatigue detecting method includes: obtaining a first physiological signal; obtaining a second physiological signal; obtaining a plurality of characteristic time differences according to the first physiological signal and the second physiological signal; and time-lapse according to the characteristic time A change trend determines a fatigue detection result. The fatigue detection method of claim 10, wherein the first physiological signal corresponds to a first physiological indicator, the second physiological signal corresponds to a second physiological indicator, and the first physiological indicator is different from the first physiological indicator Two physiological indicators. The method of claim 10, wherein the obtaining the characteristic time difference according to the first physiological signal and the second physiological signal comprises: obtaining a plurality of first characteristic times of the first physiological signal Obtaining a plurality of second feature times of the second physiological signal; and calculating a time difference between each of the first feature times and each of the second feature times as the feature time differences. The fatigue detecting method according to claim 10, wherein the step of determining the fatigue detecting result according to the changing trend of the characteristic time differences over time comprises: determining the trend of the characteristic time differences over time Whether the consistency is consistent; and if the characteristic time difference of the characteristic time is consistent with time, the fatigue detection result is determined to be a fatigue state, wherein the change trend is consistent, that is, the change trend is one of increasing or decreasing. The fatigue detecting method according to claim 10, wherein the step of determining the fatigue detecting result according to the change trend of the characteristic time difference with time comprises: according to a plurality of historical information and the time difference of the features over time This change trend determines the fatigue detection result. The method for detecting fatigue according to claim 10, further comprising: issuing a warning signal according to the fatigue detection result. The fatigue detecting method of claim 11, wherein the first physiological signal is an electrocardiogram signal, and the second physiological signal is a heart sound signal. The fatigue detecting method according to claim 16, wherein the characteristic time difference is a plurality of pre-ejection period (PEP) times.