阅读说明：本技术 Ppg信号的测量方法、装置、设备及存储介质 (PPG signal measuring method, device, equipment and storage medium ) 是由 尚春莉 于 2020-05-25 设计创作，主要内容包括：本发明实施例公开了一种PPG信号的测量方法,基于设置有PPG传感器的终端；所述方法包括：通过PPG传感器采集初始PPG信号,确定与初始PPG信号对应的初始PPG波形；获取初始PPG波形的目标特征数据；判断目标特征数据是否满足预设的特征标准条件；在目标特征数据不满足预设的特征标准条件的情况下,根据目标特征数据生成按压力度调节的提示信息,按压力度调节的提示信息用于提示用户增大或减小与PPG传感器对应的按压力度；在目标特征数据满足预设的特征标准条件的情况下,将初始PPG波形作为目标PPG波形。此外,本发明实施例还公开了一种PPG信号的测量装置、智能可穿戴设备及计算机可读存储介质。采用本发明,可提高PPG信号测量的准确性和完整性。(The embodiment of the invention discloses a PPG signal measuring method, which is based on a terminal provided with a PPG sensor; the method comprises the following steps: acquiring an initial PPG signal through a PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal; acquiring target characteristic data of an initial PPG waveform; judging whether the target characteristic data meets a preset characteristic standard condition or not; under the condition that the target characteristic data do not meet the preset characteristic standard conditions, generating pressing force degree adjustment prompt information according to the target characteristic data, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor; and taking the initial PPG waveform as the target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition. In addition, the embodiment of the invention also discloses a PPG signal measuring device, intelligent wearable equipment and a computer readable storage medium. By adopting the invention, the accuracy and the integrity of the PPG signal measurement can be improved.)

1. A method for measuring PPG signals, characterized in that it is based on a terminal provided with a PPG sensor;

the method comprises the following steps:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

2. The method of measuring PPG signals according to claim 1, wherein the step of acquiring target feature data of the initial PPG waveform further comprises:

and extracting one or more of at least one characteristic point, the number of characteristic points, the number of break points, the number of inflection points, the average curvature, the number of peak points, amplitude characteristics, average amplitude, a systolic starting point, a heartbeat wave and a dominant wave crest corresponding to the initial PPG waveform as the target characteristic data according to a preset characteristic extraction algorithm.

3. The method for measuring the PPG signal according to claim 2, wherein the step of determining whether the target feature data satisfies a preset feature criterion condition further comprises:

judging whether the number of the feature points meets a preset feature point threshold interval, and if so, judging that the target feature data meets a preset feature standard condition;

and/or judging whether the average curvature meets a preset curvature threshold interval, if so, judging that the target characteristic data meets a preset characteristic standard condition;

and/or judging whether the amplitude characteristic and/or the average amplitude meet a preset amplitude threshold interval, if so, judging that the target characteristic data meet a preset characteristic standard condition.

4. The method for measuring the PPG signal according to claim 3, wherein the step of generating a prompt message of a pressing force degree adjustment for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor according to the target feature data further comprises:

under the condition that the target characteristic data do not meet a preset characteristic standard condition, determining prompt information of pressing force degree adjustment corresponding to a comparison relation according to the comparison relation between the target characteristic data and the characteristic standard condition;

the comparison relationship comprises a first comparison relationship and a second comparison relationship, and the prompt information of the pressing force degree adjustment comprises first pressing force degree prompt information corresponding to the first comparison relationship and second pressing force degree prompt information corresponding to the second comparison relationship; the first pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is increased, and the second pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is decreased;

the first comparison relationship comprises one or more of the characteristic point number is greater than the preset characteristic point threshold interval, the average curvature is greater than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is greater than the preset amplitude threshold interval; the second comparison relationship comprises one or more of the number of the characteristic points is smaller than the preset characteristic point threshold interval, the average curvature is smaller than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is smaller than the preset amplitude threshold interval.

5. The method for measuring the PPG signal according to claim 4, wherein the prompting information adjusted according to the pressure degree further comprises an adjustment amplitude reference value;

the step of determining, according to a comparison relationship between the target feature data and the feature standard condition, a prompt message for pressing force degree adjustment corresponding to the comparison relationship further includes:

and determining a difference quantization value between the target characteristic data and the characteristic standard condition, and determining the adjustment amplitude reference value according to the difference quantization value.

6. The method for measuring the PPG signal according to claim 5, wherein the terminal is further provided with a display screen;

after the step of determining the adjusted amplitude reference value according to the difference quantization value, the method further includes:

and displaying the reference value of the adjusting amplitude based on the preset progress bar component of the display screen so as to display prompt information of the pressing force degree adjustment.

7. The method of measuring the PPG signal of claim 6, wherein the step of using the initial PPG waveform as the target PPG waveform is followed by further comprising:

calculating preset feature values according to the target PPG waveform, wherein the feature values comprise one or more of heart rate, blood pressure and blood oxygen;

and displaying the characteristic value and/or the target PPG waveform in a preset display area on the display screen.

8. The method of measuring a PPG signal according to claim 1, wherein the step of determining an initial PPG waveform corresponding to the initial PPG signal further comprises:

generating an initial PPG waveform corresponding to the initial PPG signal according to the initial PPG signal and a preset waveform generation method;

or the like, or, alternatively,

and preprocessing the initial PPG signal according to a preset preprocessing method, and generating an initial PPG waveform corresponding to the preprocessed initial PPG signal according to a preset waveform generation method, wherein the preprocessing comprises denoising processing and/or smoothing processing.

9. The method for measuring the PPG signal according to claim 1, wherein the step of generating an initial PPG waveform corresponding to the initial PPG signal according to a preset waveform generation method further comprises:

determining a compensation parameter from the initial PPG waveform;

and performing compensation correction on the initial PPG waveform according to the compensation parameters, and taking the PPG waveform after the compensation correction as the initial PPG waveform.

10. A PPG signal measuring device is characterized in that the device is based on a terminal provided with a PPG sensor;

the device comprises:

a PPG waveform acquisition unit, configured to acquire an initial PPG signal by the PPG sensor, and determine an initial PPG waveform corresponding to the initial PPG signal;

a feature data extraction unit, configured to acquire target feature data of the initial PPG waveform;

the judging unit is used for judging whether the target characteristic data meets a preset characteristic standard condition or not;

the pressing force degree adjusting unit is used for generating pressing force degree adjusting prompt information according to the target characteristic data under the condition that the target characteristic data does not meet a preset characteristic standard condition, and the pressing force degree adjusting prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and the PPG waveform determining unit is used for taking the initial PPG waveform as the target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

11. A computer-readable storage medium, storing a computer program which, when executed by a processor, causes the processor to carry out the steps of the method according to any one of claims 1 to 9.

12. A smart wearable device comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of the method of any of claims 1 to 9.

Technical Field

The invention relates to the technical field of wearable equipment and signal measurement, in particular to a method and a device for measuring PPG signals, intelligent wearable equipment and a computer-readable storage medium.

Background

With the increasing popularity of smart wearable devices, more and more manufacturers integrate various sensors on smart wearable devices (e.g., smart watches) for measuring physiological parameters of a wearer to detect and monitor the physical condition of a user. For example, a PPG (photoplethysmography) sensor is provided on a smart watch for measuring data of the wearer such as blood pressure, heart rate, blood oxygen, etc.

The principle of the PPG sensor is that an LED (Light Emitting Diode) emits infrared Light, red Light or green Light to illuminate the skin of a human body, then a PD (Photo-Diode) collects signals reflected and scattered by the skin of the human body, measures the change of reflected Light intensity caused by blood flow, thereby obtaining a pulse waveform, and extracts effective signals therefrom to calculate human body physiological parameters such as heart rate, blood pressure, blood oxygen, and the like. However, in the measurement process of the PPG sensor, the blood flow velocity of the corresponding measurement position is caused by the wearing pressure of the smart wearable device such as a smart watch or the force of the finger pressing the PPG sensor. If the pressing force is too large, the blood flow speed is influenced, even the blood flow at the finger position is blocked, so that the measurement of the pulse wave signal is influenced; if the pressing force is too small, the contact area between the human body and the PPG sensor can not cover the PPG sensor, so that ambient light enters the PD to cause light leakage and disordered pulse wave signals.

That is to say, in the related art scheme that the PPG sensor measures the pulse wave signal to measure the physiological signal of the wearer, the pressing force cannot be controlled well, so that the accuracy of the pulse wave signal measured by the PPG sensor is insufficient, and further, the accuracy of the human body physiological parameter of the wearer calculated according to the pulse wave signal is insufficient.

Disclosure of Invention

In view of the above, it is necessary to provide a method and an apparatus for measuring a PPG signal, a smart wearable device, and a computer-readable storage medium.

A method of measurement of PPG signals, the method being based on a terminal provided with a PPG sensor;

the method comprises the following steps:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

Wherein the step of obtaining target feature data of the initial PPG waveform further comprises:

and extracting one or more of at least one characteristic point, characteristic point quantity, average curvature, inflection point quantity, peak point quantity, amplitude characteristic, average amplitude, systolic start point, heavy pulse wave and main wave peak corresponding to the initial PPG waveform as the target characteristic data according to a preset characteristic extraction algorithm.

Wherein, the step of judging whether the target characteristic data meets a preset characteristic standard condition further comprises:

judging whether the number of the feature points meets a preset feature point threshold interval, and if so, judging that the target feature data meets a preset feature standard condition;

and/or judging whether the average curvature meets a preset curvature threshold interval, if so, judging that the target characteristic data meets a preset characteristic standard condition;

and/or judging whether the amplitude characteristic and/or the average amplitude meet a preset amplitude threshold interval, if so, judging that the target characteristic data meet a preset characteristic standard condition.

Wherein, the step of generating a prompt message for pressing force degree adjustment according to the target feature data, where the prompt message for pressing force degree adjustment is used to prompt a user to increase or decrease the pressing force degree corresponding to the PPG sensor, further includes:

under the condition that the target characteristic data do not meet a preset characteristic standard condition, determining prompt information of pressing force degree adjustment corresponding to a comparison relation according to the comparison relation between the target characteristic data and the characteristic standard condition;

the comparison relationship comprises a first comparison relationship and a second comparison relationship, and the prompt information of the pressing force degree adjustment comprises first pressing force degree prompt information corresponding to the first comparison relationship and second pressing force degree prompt information corresponding to the second comparison relationship; the first pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is increased, and the second pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is decreased;

the first comparison relationship comprises one or more of the characteristic point number is greater than the preset characteristic point threshold interval, the average curvature is greater than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is greater than the preset amplitude threshold interval; the second comparison relationship comprises one or more of the number of the characteristic points is smaller than the preset characteristic point threshold interval, the average curvature is smaller than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is smaller than the preset amplitude threshold interval.

The prompt message of adjusting according to the pressure degree also comprises an adjusting amplitude reference value;

the step of determining, according to a comparison relationship between the target feature data and the feature standard condition, a prompt message for pressing force degree adjustment corresponding to the comparison relationship further includes:

and determining a difference quantization value between the target characteristic data and the characteristic standard condition, and determining the adjustment amplitude reference value according to the difference quantization value.

The terminal is also provided with a display screen;

after the step of determining the adjusted amplitude reference value according to the difference quantization value, the method further includes:

and displaying the reference value of the adjusting amplitude based on the preset progress bar component of the display screen so as to display prompt information of the pressing force degree adjustment.

Wherein, after the step of using the initial PPG waveform as the target PPG waveform, the method further comprises:

calculating preset feature values according to the target PPG waveform, wherein the feature values comprise one or more of heart rate, blood pressure and blood oxygen;

and displaying the characteristic value and/or the target PPG waveform in a preset display area on the display screen.

Wherein the step of determining an initial PPG waveform corresponding to the initial PPG signal further comprises:

generating an initial PPG waveform corresponding to the initial PPG signal according to the initial PPG signal and a preset waveform generation method;

or the like, or, alternatively,

and preprocessing the initial PPG signal according to a preset preprocessing method, and generating an initial PPG waveform corresponding to the preprocessed initial PPG signal according to a preset waveform generation method, wherein the preprocessing comprises denoising processing and/or smoothing processing.

Wherein the step of generating an initial PPG waveform corresponding to the initial PPG signal according to a preset waveform generation method further includes:

determining a compensation parameter from the initial PPG waveform;

and performing compensation correction on the initial PPG waveform according to the compensation parameters, and taking the PPG waveform after the compensation correction as the initial PPG waveform.

A PPG signal measuring device is based on a terminal provided with a PPG sensor;

the device comprises:

a PPG waveform acquisition unit, configured to acquire an initial PPG signal by the PPG sensor, and determine an initial PPG waveform corresponding to the initial PPG signal;

a feature data extraction unit, configured to acquire target feature data of the initial PPG waveform;

the judging unit is used for judging whether the target characteristic data meets a preset characteristic standard condition or not;

the pressing force degree adjusting unit is used for generating pressing force degree adjusting prompt information according to the target characteristic data under the condition that the target characteristic data does not meet a preset characteristic standard condition, and the pressing force degree adjusting prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and the PPG waveform determining unit is used for taking the initial PPG waveform as the target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

A smart wearable device comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

A computer-readable storage medium storing a computer program which, when executed by a processor, causes the processor to perform the steps of:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

The embodiment of the invention has the following beneficial effects:

after the method and the device for measuring the PPG signal, the intelligent wearable device and the computer readable storage medium are adopted, in the process of measuring the PPG signal of the user through the PPG sensor, the corresponding PPG waveform is determined according to the PPG signal obtained through measurement, then the feature analysis is carried out on the PPG waveform to determine whether the feature of the PPG waveform meets the preset feature standard condition or not, only under the condition that the feature of the PPG waveform meets the preset feature standard condition, the corresponding PPG waveform is taken as the target PPG waveform, on the contrary, under the condition that the feature of the PPG waveform does not meet the preset feature standard condition, the pressing force degree between the PPG sensor and the human body is considered to be too large or too small in the process of measuring the PPG signal of the user through the PPG sensor, adjustment is needed, under the condition, the prompt information for adjusting the pressing force degree is generated according to the feature of the PPG waveform, the user is prompted to adjust the pressure degree between the PPG sensor and the human body, so that the PPG signal is measured again, the PPG signal meeting the preset characteristic standard condition is obtained, and the measurement of the PPG signal of the user is completed.

That is to say, in the embodiment of the present invention, the characteristic analysis is performed on the measured PPG waveform to determine whether the pressing force between the PPG sensor and the human body is appropriate, and the user is reminded to adjust when the pressing force is too large or too small, so that the situation that the measured PPG signal has incomplete characteristics is avoided, the accuracy and the integrity of the measurement of the PPG signal are improved, the analysis accuracy of the subsequent further analysis according to the PPG signal is improved, and the user experience is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Wherein:

fig. 1 is a schematic flow chart of a method for measuring PPG signals according to an embodiment;

FIG. 2 is a diagram illustrating a progress bar component in one embodiment;

FIG. 3 is a schematic diagram of a display interface in one embodiment;

fig. 4 is a schematic structural diagram of a PPG signal measurement device according to an embodiment;

fig. 5 is a schematic diagram of a computer device for executing the method for measuring the PPG signal.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to solve the above technical problem that the wearing pressure or the pressing force degree affects the accuracy of the PPG sensor in measuring the pulse wave signal, in this embodiment, a method for measuring the PPG signal is provided, and feature analysis is performed on the measured PPG signal to prompt the user to change the wearing pressure or the pressing force degree when the feature does not meet the requirement, so as to obtain the PPG signal and the PPG waveform meeting the requirement, thereby improving the accuracy and the integrity of the measurement of the PPG signal and the PPG waveform.

Specifically, referring to fig. 1, fig. 1 provides a schematic flow chart of a method for measuring a PPG signal.

In this embodiment, the method for measuring the PPG signal is implemented by a terminal provided with a PPG sensor, for example, a smart wearable device such as a smart watch, or other terminal devices provided with a PPG sensor and measuring physiological parameters of a user. Wherein. The PPG signal refers to a signal measured from a PPG sensor, which may be a pulse wave signal or a combined signal including a pulse wave signal.

In this embodiment, the PPG sensor may be disposed on a contact surface of the smart wearable device and the human body, for example, a back surface of the smart watch, and in a case where the smart wearable device is worn by the user, the PPG sensor is in contact with the human body, so that the relevant physiological parameter of the user may be measured. In this case, the magnitude of the wearing pressure (the degree of pressing of the PPG sensor against the external skin of the person) may influence the measurement of the PPG signal. In another embodiment, the PPG sensor may also be arranged external to the smart wearable device, e.g. on the side or front of the smart watch, and the user may measure the relevant physiological parameter of the user by touching or pressing the PPG sensor with a finger. In this case, the pressing force of the finger may affect the measurement of the PPG signal.

In this embodiment, whether the measured PPG signal meets the condition is determined by analyzing the measured PPG signal, and then it is determined whether the user needs to be prompted to adjust the degree of pressing (including the degree of pressing corresponding to the wearing pressure and the degree of pressing of the finger). For convenience of description, the pressing force degree when the finger presses the sensor is described later, but the pressing force degree corresponding to the wearing pressure when the user wears the smart wearable device is also included.

Specifically, referring to fig. 1, the method for measuring a PPG signal includes steps S102 to S110 shown in fig. 1:

step S102: acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal.

Under the condition that the PPG sensor is in contact with the skin of a human body, the LED emits infrared light, red light or green light to irradiate the skin of the human body, signals reflected and scattered by the skin of the human body are collected through the PD, and a corresponding initial PPG signal is obtained, wherein the PPG signal is a pulse wave signal obtained through measurement (in another embodiment, the PPG signal can also be a combined signal containing the pulse wave signal obtained through measurement). Processing the PPG signal may generate a corresponding waveform, i.e., an initial PPG waveform corresponding to the initial PPG signal. The PPG waveform is a waveform corresponding to the PPG signal, for example, a pulse wave waveform corresponding to the pulse wave signal, or a combined waveform including the pulse wave waveform. In this embodiment, the initial PPG waveform may be used for presentation, so that the user knows the corresponding physiological signal change according to the initial PPG waveform, or the initial PPG waveform may be used for calculating the corresponding physiological parameter of the user, for example, calculating the physiological parameter of the user, such as the heart rate or the blood pressure, according to the initial PPG waveform.

Specifically, according to the initial PPG signal, an initial PPG waveform corresponding to the initial PPG signal is generated according to a preset waveform generation method. Alternatively, in other embodiments, pre-processing of the initial PPG signal is also required to improve the signal quality of the initial PPG signal. Specifically, the initial PPG signal is preprocessed according to a preset preprocessing method, and an initial PPG waveform corresponding to the preprocessed initial PPG signal is generated according to a preset waveform generation method, where the preprocessing includes denoising and/or smoothing. It should be noted that the foregoing preprocessing is not limited to the denoising processing and/or the smoothing processing.

In another embodiment, in order to reduce the impact of different compression conditions on the PPG signal measurement, in case of generating a PPG waveform, a certain compensation and correction may also be performed on the initial PPG waveform to get a more optimized PPG waveform after the compensation correction.

In a specific embodiment, after the initial PPG waveform is generated according to the initial PPG signal, a compensation parameter corresponding to the initial PPG waveform is determined; and then, performing compensation correction on the initial PPG waveform according to the compensation parameters, and taking the PPG waveform after compensation correction as the updated initial PPG waveform. The compensation parameter may be determined according to the pressure detected by a pressure sensor that is additionally provided, or may be determined by analyzing the pressing force of the measured PPG waveform. It should be noted that, in this embodiment, compensating and correcting the PPG waveform may avoid correcting the PPG waveform under the condition that the PPG signal is slightly weak or strong, reduce the influence of different wearing conditions or finger pressing conditions on the PPG waveform, and further improve the accuracy of the measurement of the PPG signal.

Step S104: target feature data of the initial PPG waveform is acquired.

The characteristic data of the initial PPG waveform includes one or more of characteristic points, number of characteristic points, mean curvature, number of peak points, amplitude characteristics, mean amplitude, systolic start point, beat wave, dominant wave peak, etc., which characteristic data or characteristic data to employ may be determined, in particular implementations, based on the need for PPG waveform analysis. Specifically, the process of extracting the feature data of the initial PPG waveform includes extracting one or more of at least one feature point, a number of feature points, a number of inflection points, an average curvature, a number of peak points, an amplitude feature, an average amplitude, a systolic start point, a rebble wave, and a dominant wave corresponding to the initial PPG waveform according to a preset feature extraction algorithm, and then using the extracted feature data as target feature data.

The characteristic points comprise inflection points, inflection points and the like, the number of the characteristic points is the number of the characteristic points such as the inflection points, the inflection points and the like, the characteristic points or the number of the characteristic points can determine the characteristic change points of the PPG waveform, and under a normal condition, the characteristic points and the number of the characteristic points of the PPG waveform should be within a certain range. The number of peak points is the number of points corresponding to the peak in the PPG waveform, and in a normal case, the number of peak points of the PPG waveform should be kept within a certain range or the like.

The average curvature is an average value calculated from curvatures corresponding to curves of the PPG waveform, and under normal conditions, the curvature of the PPG waveform is kept within a certain range. The amplitude characteristic is the amplitude corresponding to the PPG waveform and the amplitude change characteristic corresponding to the needle, the average amplitude is the average value of the amplitude corresponding to the PPG waveform, and under the normal condition, the amplitude characteristic or the average amplitude should be kept in a certain range.

The cardiac cycle is a mechanical activity cycle formed by one contraction and relaxation of the heart, wherein the contraction phase comprises a ventricular contraction phase, and a contraction phase starting point is a corresponding ventricular contraction phase starting point. Under normal conditions, the significant wave and the main wave peak are visible, and if the significant wave and the main wave peak are not visible, the measurement is not accurate or the user has corresponding pathological changes.

Step S106: judging whether the target characteristic data meets a preset characteristic standard condition or not;

if yes, go to step S108: taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition;

if not, go to step S110: and generating prompt information of pressing force degree adjustment according to the target characteristic data, wherein the prompt information of pressing force degree adjustment is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor.

If the target characteristic data meets the preset characteristic standard data, the initial PPG waveform obtained by current measurement can be used as the target PPG waveform, and subsequent calculation of physiological parameters and monitoring of the physical condition of the user are carried out. If the target characteristic data does not meet the preset characteristic standard data, the initial PPG waveform obtained by current measurement cannot be used as the target PPG waveform, and subsequent calculation of physiological parameters and detection of the physical condition of the user are required to be measured again. In this embodiment, the reason why the initial PPG waveform does not satisfy the preset characteristic standard condition is mainly caused by the fact that the pressing force corresponding to the PPG sensor is too large or too small, and therefore, the user is required to readjust the pressing force with the PPG sensor, so as to obtain the target PPG waveform satisfying the preset characteristic standard condition and obtain a better and more complete target PPG waveform.

Specifically, the process of determining whether the target feature data meets the preset feature standard condition may be determined according to a relationship between different feature data and corresponding feature standard conditions.

And under the condition that the number of the feature points is within a certain range (the number of the feature points meets a preset feature point threshold interval), judging that the initial PPG waveform meets a preset feature standard condition, and on the contrary, if the number of the feature points is not within the certain range (too large or too small), judging that the initial PPG waveform meets the preset feature standard condition.

And if the average curvature is within a certain range (the average curvature meets a preset curvature threshold interval), the initial PPG waveform is judged to meet a preset characteristic standard condition, and if the average curvature is not within the certain range (too large or too small), the initial PPG waveform is judged not to meet the preset characteristic standard condition.

In the case where the amplitude characteristic and/or the average amplitude is within a certain range (the amplitude characteristic and/or the average amplitude satisfies a preset amplitude threshold interval), the initial PPG waveform is determined to satisfy the preset characteristic standard condition, whereas if the amplitude characteristic and/or the average amplitude is not within a certain range (too large or too small), the initial PPG waveform is determined not to satisfy the preset characteristic standard condition.

In other embodiments, the comparison relationship between the target characteristic data such as the above characteristic points, the number of inflection points, the number of peak points, the systolic start point, the beat wave, the main wave peak, and the like, and the preset characteristic standard condition may be further defined, which is not described in detail herein.

It should be noted that, for different users, the processing unit is configured to determine whether the target feature data meets the feature standard condition in the preset feature standard condition, and may further perform personalized setting according to the different users, for example, the number of feature points and the amplitude corresponding to the PPG waveforms of the different users have a certain difference in a certain range, and if the processing unit determines according to the unified standard, the processing unit may also have a certain inaccuracy in measurement for the users with different physical conditions, so in this embodiment, in order to improve the accuracy of the PPG signal measurement, before step S106, a user personalized parameter needs to be obtained, and the preset feature standard condition is determined according to the personalized parameter. Wherein the user personalized parameters comprise one or more of age, gender, height, weight, physical examination data, historical PPG detection data, and the like.

Under the condition that target characteristic data extracted from the initial PPG waveform does not meet a preset characteristic standard condition, the problem exists in the current PPG signal measurement, and adjustment is needed. As described above, the reason for the inaccuracy of the PPG signal measurement includes that the degree of pressing force is too large or too small, and therefore, in this embodiment, a prompt message for adjusting the degree of pressing force is generated according to the target feature data to prompt the user to adjust the degree of pressing force. However, whether the pressing force level is increased or decreased needs to be specifically determined based on the target feature data.

Specifically, when the target characteristic data does not meet a preset characteristic standard condition, determining a prompt message for pressing force degree adjustment corresponding to a comparison relationship according to the comparison relationship between the target characteristic data and the characteristic standard condition; the comparison relationship comprises a first comparison relationship and a second comparison relationship, and the prompt information of the pressing force degree adjustment comprises first pressing force degree prompt information corresponding to the first comparison relationship and second pressing force degree prompt information corresponding to the second comparison relationship; the first pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is increased, and the second pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is decreased; the first comparison relationship comprises one or more of the characteristic point number is greater than the preset characteristic point threshold interval, the average curvature is greater than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is greater than the preset amplitude threshold interval; the second comparison relationship comprises one or more of the number of the characteristic points is smaller than the preset characteristic point threshold interval, the average curvature is smaller than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is smaller than the preset amplitude threshold interval.

For example, when the number of feature points is greater than a preset feature point threshold interval, it is assumed that the target feature data and the feature standard condition satisfy a first comparison relationship, and in this case, the generated prompt information is first pressing force degree prompt information for prompting an increase in the pressing force degree corresponding to the PPG sensor. For example, when the number of feature points is smaller than a preset feature point threshold interval, it is considered that the target feature data and the feature standard condition satisfy the second comparison relationship, and in this case, the generated prompt information is second pressing force degree prompt information for prompting reduction of the pressing force degree corresponding to the PPG sensor.

In this embodiment, in order to prompt the user to increase or decrease the pressing force level corresponding to the PPG sensor, the above-mentioned presentation of the first pressing force level prompt information and the second pressing force level prompt information may be presented in the form of sound, vibration, or a display screen.

Further, in order to improve the accuracy of the measurement of the PPG signal, the user needs to be informed of the amplitude to be adjusted when the prompt information for adjusting the pressing force degree is displayed for the user, so that the user can accurately adjust the pressing force degree to the required pressing force degree to acquire the PPG signal meeting the requirements, i.e., a more complete and better PPG waveform is acquired, thereby improving the accuracy and integrity of the measurement of the PPG signal.

Specifically, in the process of generating the prompt message for pressing force degree adjustment, a difference quantization value between the target characteristic data and the characteristic standard condition is determined according to the target characteristic data, an adjustment amplitude reference value is determined according to the determined difference quantization value, and the adjustment amplitude reference value is displayed in the prompt message for displaying pressing force degree adjustment.

The calculation of the difference quantization value between the target feature data and the feature standard condition and the adjustment amplitude reference value is exemplarily described below. It should be noted that the calculation method of the quantized difference value and the adjustment amplitude reference value between the target feature data and the feature standard condition is not limited to the following calculation method, and may be any method that describes the difference situation between the target feature data and the feature standard condition and calculates the adjustment amplitude reference value according to the difference situation, and is not limited herein.

The description is given in terms of the number of feature points.

The number of the feature points extracted according to the initial PPG waveform is N1, and the threshold interval of the feature points corresponding to the number of the feature points in the feature standard condition is [ M1, M2]]If N1E [ M1, M2]]And then, the number of the characteristic points is indicated to meet the characteristic standard condition, and the initial PPG waveform can be used as the target PPG waveform. Further, if, for example,the number of feature points is not satisfied with the feature standard condition. In this case, N1 and [ M1, M2] need to be calculated]The difference between them E1.

Specifically, in the case of N1< M1:

in the case of N1> M2:

that is, the difference quantization value between the target feature data and the feature criterion condition is a ratio of a difference between the number of feature points and an end point of the number of adjacent feature points in the feature point threshold interval to an average value of the feature point threshold interval, where N1< M1, E1<0 corresponds to a case where the number of feature values is too small and the degree of pressing force needs to be reduced, and N1> M2 corresponds to a case where the number of feature values is too large and the degree of pressing force needs to be increased, and E1>0 corresponds to a case where the number of feature values is too large.

Further, the determination process of the adjustment amplitude reference value is as follows.

First, a value range of the pressing force is initialized, for example, in a case where a possible pressing force value is (a, b), a corresponding relationship between the pressing force and (-1,1) is constructed, where, in a case where 0 corresponds to the best pressing force value, the corresponding pressing force value c may be obtained through experiments. In the case where the pressing force is (c-epsilon, c + epsilon) (where epsilon is a constant greater than 0 and less than 1), it corresponds to the feature point number satisfying the feature criterion condition, i.e., to N1 e [ M1, M2 ].

The adjustment amplitude reference value E2 is calculated as follows:

E2＝f(E1)

where f (E1) is a correspondence between mapping the difference quantization value E1 to (-1,1), thereby determining the adjustment amplitude reference value E2.

That is, the finally calculated and determined adjustment amplitude reference value E2 is a value of (-1,1), and the amplitude that should be increased or decreased is determined according to the value of E2. For example, if E2 is-0.5, it indicates that the degree of pressing force needs to be reduced, and the reduced adjustment amplitude reference value is-0.5.

Further, in the process of displaying the adjustment amplitude reference value, the adjustment amplitude reference value may be displayed by a preset progress bar assembly and displayed on a display screen of the terminal. Referring specifically to fig. 2, fig. 2 shows a preset progress bar assembly showing the adjustment amplitude reference. As shown in fig. 2, the section Q2 [ [ Q2], Q3] corresponds to (c-epsilon, c + epsilon) ] and indicates that when the pressing force falls within the section, the pressing force is not adjusted, the section Q1 [ [ Q1 ], Q2] corresponds to a case where the pressing force is small, the section Q2 corresponding to Q1 is equal to or infinitely close to 1, the section Q3 [ [ Q3], Q4] corresponds to a case where the pressing force is too large, and the section Q4 corresponds to a case where the section E2 is equal to or wirelessly close to-1.

In the application scenario shown in fig. 2, a value on the progress bar assembly is determined according to the magnitude of the adjustment amplitude reference value E2, and then the user is prompted in the form of a progress bar to adjust the pressing force. Further, in this embodiment, under the condition of displaying the progress bar, other prompt information can be displayed in the form of characters and the like, so that the user can quickly adjust the pressing strength.

As mentioned previously, the display screen is arranged on the terminal such as the intelligent wearable device, and the preset progress bar assembly and other prompt information can be displayed. Furthermore, more information can be displayed through the display screen. In a specific embodiment, after the initial PPG waveform is acquired, the corresponding initial PPG waveform may be displayed in a preset display area on the display screen, and in the case that the initial PPG waveform is determined to be the target PPG waveform, the target PPG waveform is displayed in the same preset display area on the display screen.

Further, after the target PPG waveform is determined, one or more preset characteristic values, such as heart rate, blood pressure, blood oxygen and the like, are calculated according to the determined target PPG waveform, and then the calculated characteristic values are displayed in a preset display area on a display screen, so that a user can directly and intuitively know the current physiological parameter data, such as heart rate, blood pressure and the like, through the display screen to know the current physical condition.

In particular, referring to fig. 3, fig. 3 shows an example of displaying the initial/target PPG waveforms and corresponding heart rate, blood pressure, blood oxygen, and other characteristic values in a preset display area on the display screen.

Further, referring to fig. 4, fig. 4 is a schematic structural diagram of a measurement apparatus for a PPG signal provided in an embodiment of the present invention, where the measurement apparatus for a PPG signal includes:

a PPG waveform acquisition unit 102, configured to acquire an initial PPG signal by the PPG sensor, and determine an initial PPG waveform corresponding to the initial PPG signal;

a feature data extraction unit 104, configured to acquire target feature data of the initial PPG waveform;

a judging unit 106, configured to judge whether the target feature data meets a preset feature standard condition;

the pressing force degree adjusting unit 108 is configured to generate, according to the target feature data, pressing force degree adjustment prompting information when the target feature data does not meet a preset feature standard condition, where the pressing force degree adjustment prompting information is used to prompt a user to increase or decrease a pressing force degree corresponding to the PPG sensor;

a PPG waveform determining unit 110, configured to take the initial PPG waveform as the target PPG waveform if the target feature data meets a preset feature criterion condition.

The feature data extraction unit 104 is further configured to extract, according to a preset feature extraction algorithm, one or more of at least one feature point, a number of feature points, an average curvature, a number of peak points, an amplitude feature, an average amplitude, a systolic start point, a heartbeat wave, and a dominant wave peak corresponding to the initial PPG waveform as the target feature data.

The determining unit 106 is further configured to determine whether the number of the feature points meets a preset feature point threshold interval, and if so, determine that the target feature data meets a preset feature standard condition; and/or judging whether the average curvature meets a preset curvature threshold interval, if so, judging that the target characteristic data meets a preset characteristic standard condition; and/or judging whether the amplitude characteristic and/or the average amplitude meet a preset amplitude threshold interval, if so, judging that the target characteristic data meet a preset characteristic standard condition.

The pressing force degree adjusting unit 108 is further configured to determine, when the target feature data does not meet a preset feature standard condition, a prompt message for pressing force degree adjustment corresponding to a comparison relationship between the target feature data and the feature standard condition according to the comparison relationship between the target feature data and the feature standard condition; the comparison relationship comprises a first comparison relationship and a second comparison relationship, and the prompt information of the pressing force degree adjustment comprises first pressing force degree prompt information corresponding to the first comparison relationship and second pressing force degree prompt information corresponding to the second comparison relationship; the first pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is increased, and the second pressing force degree prompt information is used for prompting that the pressing force degree corresponding to the PPG sensor is decreased; the first comparison relationship comprises one or more of the characteristic point number is greater than the preset characteristic point threshold interval, the average curvature is greater than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is greater than the preset amplitude threshold interval; the second comparison relationship comprises one or more of the number of the characteristic points is smaller than the preset characteristic point threshold interval, the average curvature is smaller than the preset curvature threshold interval, and the amplitude characteristic and/or the average amplitude is smaller than the preset amplitude threshold interval.

The prompt message of adjusting according to the pressure degree also comprises an adjusting amplitude reference value; the pressing force degree adjusting unit 108 is further configured to determine a difference quantization value between the target feature data and the feature standard condition, and determine the adjustment amplitude reference value according to the difference quantization value.

The pressing force degree adjusting unit 108 is further configured to display the adjustment amplitude reference value based on a preset progress bar assembly, so as to display prompt information of the pressing force degree adjustment.

As shown in fig. 4, the measurement apparatus for PPG signals further includes a feature calculation presentation unit 112, configured to calculate preset feature values according to the target PPG waveform, where the feature values include one or more of heart rate, blood pressure, and blood oxygen; displaying the characteristic value and/or the target PPG waveform in a preset display area.

The PPG waveform acquisition unit 102 is further configured to generate an initial PPG waveform corresponding to the initial PPG signal according to the initial PPG signal and a preset waveform generation method; or, preprocessing the initial PPG signal according to a preset preprocessing method, and generating an initial PPG waveform corresponding to the preprocessed initial PPG signal according to a preset waveform generation method, wherein the preprocessing includes denoising and/or smoothing.

Wherein the PPG waveform acquisition unit 102 is further configured to determine compensation parameters for the initial PPG waveform; and performing compensation correction on the initial PPG waveform according to the compensation parameters, and taking the PPG waveform after the compensation correction as the initial PPG waveform.

FIG. 5 is a diagram illustrating an internal structure of a computer device in one embodiment. The computer device may specifically be a terminal, and may also be a server. As shown in fig. 5, the computer device includes a processor, a memory, and a network interface connected by a system bus. Wherein the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program which, when executed by the processor, may cause the processor to implement the method of measuring the PPG signal. The internal memory may also have stored therein a computer program which, when executed by the processor, causes the processor to perform a method of measuring PPG signals. Those skilled in the art will appreciate that the architecture shown in fig. 5 is merely a block diagram of some of the structures associated with the disclosed aspects and is not intended to limit the computing devices to which the disclosed aspects apply, as particular computing devices may include more or less components than those shown, or may combine certain components, or have a different arrangement of components.

In one embodiment, a smart wearable device is presented, comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

In one embodiment, a computer-readable storage medium is proposed, in which a computer program is stored which, when executed by a processor, causes the processor to carry out the steps of:

acquiring an initial PPG signal by the PPG sensor, and determining an initial PPG waveform corresponding to the initial PPG signal;

acquiring target characteristic data of the initial PPG waveform;

judging whether the target characteristic data meets a preset characteristic standard condition or not;

generating pressing force degree adjustment prompt information according to the target characteristic data under the condition that the target characteristic data do not meet preset characteristic standard conditions, wherein the pressing force degree adjustment prompt information is used for prompting a user to increase or decrease the pressing force degree corresponding to the PPG sensor;

and taking the initial PPG waveform as a target PPG waveform under the condition that the target characteristic data meets a preset characteristic standard condition.

The embodiment of the invention has the following beneficial effects:

after the method and the device for measuring the PPG signal, the intelligent wearable device and the computer readable storage medium are adopted, in the process of measuring the PPG signal of the user through the PPG sensor, the corresponding PPG waveform is determined according to the PPG signal obtained through measurement, then the feature analysis is carried out on the PPG waveform to determine whether the feature of the PPG waveform meets the preset feature standard condition or not, only under the condition that the feature of the PPG waveform meets the preset feature standard condition, the corresponding PPG waveform is taken as the target PPG waveform, on the contrary, under the condition that the feature of the PPG waveform does not meet the preset feature standard condition, the pressing force degree between the PPG sensor and the human body is considered to be too large or too small in the process of measuring the PPG signal of the user through the PPG sensor, adjustment is needed, under the condition, the prompt information for adjusting the pressing force degree is generated according to the feature of the PPG waveform, the user is prompted to adjust the pressure degree between the PPG sensor and the human body, so that the PPG signal is measured again, the PPG signal meeting the preset characteristic standard condition is obtained, and the measurement of the PPG signal of the user is completed.

That is to say, in the embodiment of the present invention, the characteristic analysis is performed on the measured PPG waveform to determine whether the pressing force between the PPG sensor and the human body is appropriate, and the user is prompted to adjust when the pressing force is too large or too small, so that a situation that the measured PPG signal has incomplete characteristics is avoided, the accuracy of the measurement of the PPG signal is improved, the accuracy of the subsequent analysis performed according to the PPG signal is improved, and the user experience is improved.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by a computer program, which can be stored in a non-volatile computer-readable storage medium, and can include the processes of the embodiments of the methods described above when the program is executed. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.