阅读说明：本技术 一种ppg脉搏波模拟仪 (PPG pulse wave simulator ) 是由 刘阳 夏丽娇 裴治国 于 2021-10-14 设计创作，主要内容包括：本申请公开了一种PPG脉搏波模拟仪,包括主机、仿真手腕和智能终端,所述仿真手腕包括仿真主体和光线入射窗口,在光线入射窗口内沿光线入射路径依次设置遮光环、减光片、分光片、液晶光阀和反射片,光路周边设置黑色吸光层,所述智能终端通过USB或BT与主机通讯连接,所述仿真手腕与主机可拆卸式连接,在主机上设有用于插入仿真手腕的凹槽,在凹槽和仿真手腕连接位置分别设有对应连接的金属触点、以及对应连接的磁吸件,所述仿真主体内设有连接液晶光阀的控制电路,表面设有触点连接指示灯。本申请可用于对各类型可穿戴健康设备的PPG指标进行检测,通过对光路的反射、透射控制,较为真实地模拟出手腕的光学特性,检测结果贴近实际情况。(The application discloses PPG pulse wave analog instrument, including host computer, emulation wrist and intelligent terminal, the emulation wrist includes emulation main part and light incident window, sets gradually shading ring, dimmer, beam splitter, liquid crystal light valve and reflector plate along light incident path in the light incident window, and the light path periphery sets up black light-absorbing layer, intelligent terminal passes through USB or BT and is connected with the host computer communication, the emulation wrist is connected with the host computer is detachable, is equipped with the recess that is used for inserting the emulation wrist on the host computer, is equipped with the metal contact that corresponds the connection respectively at recess and emulation wrist hookup location and corresponds the magnetism piece of connecting, be equipped with the control circuit of connecting the liquid crystal light valve in the emulation main part, the surface is equipped with the contact connection pilot lamp. The application can be used for detecting PPG indexes of various types of wearable health equipment, the optical characteristics of the wrist can be simulated really through reflection and transmission control of the light path, and the detection result is close to the actual situation.)

1. The utility model provides a PPG pulse wave simulator, its characterized in that, includes host computer (1) and human simulation structure, human simulation structure includes emulation main part (21) and light incident window (22) set gradually dimmer (24), beam splitter (25), liquid crystal light valve (26) and reflector plate (27) along light incident path in light incident window (22), host computer (1) is connected with human simulation structure electricity be equipped with the control circuit who connects liquid crystal light valve (26) in emulation main part (21).

2. The PPG pulse wave simulator according to claim 1, wherein a light shield (23) is further provided at the entrance of the light entrance window (22).

3. The PPG pulse-wave simulator according to claim 2, characterized in that a black light-absorbing layer (28) is arranged on the inner wall of the light entrance window (22).

4. The PPG pulse wave simulator according to claim 3, further comprising an intelligent terminal (3), wherein the intelligent terminal (3) is provided with a human-computer interface, and the intelligent terminal (3) is in communication connection with the host (1) through USB or BT.

5. The PPG pulse wave simulator according to claim 4, wherein said human body simulation structure is a simulated wrist (2).

6. The PPG pulse wave simulator according to any one of claims 1-5, wherein the light incident window (22) is detachably connected with the simulation main body (21); or the dimmer (24) and the light splitting sheet (25) are detachably connected with the light incidence window (22).

7. The PPG pulse wave simulator according to any of claims 1-5, wherein the human body simulation structure is detachably connected to the host (1).

8. The PPG pulse wave simulator according to claim 7, wherein said host (1) is provided with a groove (11) for inserting and fixing the human body simulation structure, and the groove (11) and the insertion end of the human body simulation structure are respectively provided with a metal contact (4) for corresponding connection.

9. The PPG pulse wave simulator according to claim 8, wherein a magnetic element (5) or a snap-fit component is respectively disposed in the groove (11) and at a corresponding position of the insertion end of the human body simulation structure.

10. The PPG pulse wave simulator according to claim 9, wherein an indicator light for indicating whether metal contacts are in normal contact is further provided on the host (1).

Technical Field

The invention relates to the technical field of wearable equipment detection, in particular to a PPG pulse wave simulator.

Background

Photoplethysmography (PPG) is a technique that can non-invasively detect physiological parameters such as human pulse and blood oxygen saturation, and is widely applied to health products such as medical instruments and smart watches. The working principle of the device is that specific light is emitted to a human body, after the light is absorbed, reflected and transmitted by human tissues, an optical sensor acquires an optical signal returned by the human body and converts the optical signal into an electric signal, and the electric signal is analyzed and processed through an algorithm and corresponding physiological parameters are extracted.

Normally, when light acts on muscles, bones, veins and other connective tissues, their absorption of light is substantially constant, while for light impinging on arterial blood vessels, the light is modulated due to the dynamic blood in the blood vessel and the periodic variation of the light with the heart beat, and the output signal of the optical sensor is the result of the superposition of the two different light beams, the former determining the DC component of the output signal and the latter determining the AC component of the output signal.

With the rapid development of wearable health products and market scales, PPG technologies are applied to more and more wearable products, and in order to evaluate the quality of related products, PPG indicator detection is inevitably required. The current PPG index detection adopts a PPG blood oxygen simulator, and the principle is as follows: the PPG blood oxygen simulator receives the optical information sent by the product to be detected and converts the optical information into corresponding electrical signals, then modulates the signals according to the human pulse condition simulated as required, finally converts the modulated electrical signals into optical signals, returns to the product to be detected, and judges the detection precision of the product to be detected when the product is used by comparing the physiological parameters calculated by the product with the simulation parameters set in the PPG blood oxygen simulator. However, this method has the following drawbacks:

1. the received light signal of wearable healthy product in the use is that its self sends the result after human tissue processing, belongs to the same light source, and when detecting through PPG blood oxygen simulator, the received light signal is that PPG blood oxygen simulator self sends after the modulation, belongs to different light sources, consequently can not really simulate out the practical application scene of product, and product quality testing result is not accurate.

2. The light source of the PPG blood oxygen simulator is red light and infrared light, and the most commonly adopted light source of most wearable health products (such as intelligent watches) is green light, so the PPG blood oxygen simulator cannot realize the PPG index detection of the intelligent watches which rely on the green light to carry out pulse detection, and the actual application range of the method is small.

3. The PPG oximeter is designed for the scene simulation of the blood oxygen saturation, so pulse wave simulation under the conditions of interference, baseline drift, motion artifact and the like cannot be set, and meanwhile, the cost and the selling price are higher due to different design concepts, which is not beneficial to wide application.

In summary, a new technical scheme for performing PPG indicator detection on wearable health products with a wide application range and high scene simulation reality is needed in the industry.

Disclosure of Invention

An object of this application is to provide a PPG pulse wave analog instrument, the optical characteristic through comparatively really simulating human physiology structure improves the precision that PPG index detected. The technical scheme of the application is as follows:

the utility model provides a PPG pulse wave simulator, includes host computer and human simulation structure, human simulation structure includes emulation main part and light incident window set gradually dimmer, beam splitter, liquid crystal light valve and reflector plate along light incident path in the light incident window, the host computer is connected with human simulation structure electricity be equipped with the control circuit of connecting the liquid crystal light valve in the emulation main part.

For the technology of the application, the simulation of the optical property of the blood vessel pulsation and the simulation of the optical property of different skin colors can be realized simultaneously. Specifically, 1, because the reflection amount of the reflector plate is fixed, the reflection amount of reflected light can be controlled by controlling the light transmission amount of the liquid crystal light valve, the light transmission amount and the light transmission change frequency of the liquid crystal light valve can be accurately controlled by a precise clock in the host, and the optical property of blood vessel pulsation is simulated; 2. the dimmer and the light splitting sheet can respectively play a dimming and light splitting role with a certain transmittance ratio on light with the wavelength of 400-1100 nm, so that the optical properties of different skin colors and different tissues and bones can be simulated through a combination form of different transmittance ratios.

In some specific embodiments, a light shield is further disposed at an entrance of the light incidence window.

In some specific embodiments, a black light absorbing layer is disposed on an inner wall of the light incidence window.

In some specific embodiments, the intelligent terminal further comprises an intelligent terminal, wherein a human-computer interaction interface is arranged on the intelligent terminal, and the intelligent terminal is in communication connection with the host through a USB or a BT.

In some specific embodiments, the body-emulating structure is an emulated wrist.

In some specific embodiments, the light incident window is detachably connected with the simulation main body; or the dimmer and the light splitting sheet are detachably connected with the light incidence window.

In some embodiments, the body simulator is detachably connected to the host.

In some specific embodiments, the host is provided with a groove for inserting and fixing the human body simulation structure, and the groove and the insertion end of the human body simulation structure are respectively provided with a metal contact correspondingly connected.

In some specific embodiments, a magnetic member or a fastening member is respectively disposed in the groove and at a corresponding position of the insertion end of the human body simulation structure.

In some specific embodiments, an indicator light for indicating whether the metal contact is normally contacted is further arranged on the host machine.

The technical scheme provided by the application has at least the following beneficial effects:

1. this application is used for carrying out pulse measuring's equipment through PPG technique to intelligent wrist-watch, bracelet etc. and carry out PPG index and detect, simulates out comparatively real detection environment through the reflection control to the light path, and introduced DC component and AC component simultaneously, more presses close to the processing and processing process of human structure to light, has improved the precision of testing result.

2. The application provides a PPG pulse wave analog instrument has utilized the light source of waiting to detect product itself, consequently to the current product in the market, no matter it is green glow, ruddiness, infrared light or other wavelength that it is used for PPG to measure, all applicable, the practicality is strong.

3. This application is designed into magnetism with host computer and emulation wrist and is inhaled formula isolating construction and adopt metal contact connected mode, is convenient for change emulation wrist to simulate the product application scene under the different conditions, it is convenient during the dismantlement, firm during the installation.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that other drawings may be derived from those drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic connection diagram of a PPG pulse wave simulator provided in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of the host and the simulated wrist in FIG. 1;

FIG. 3 is a schematic view of the structure of the light incident window in FIG. 2;

FIG. 4 is a schematic diagram of the structure of the liquid crystal light valve and the reflective sheet of FIG. 3;

in the figure: 01, a smart watch, 1, a host, 11 and a groove; 2. the simulation wrist comprises a simulation wrist 21, a simulation main body 22, a light incidence window 23, a light shield 24, a light reduction sheet 25, a light splitting sheet 26, a liquid crystal light valve 27, a reflector 28 and a black light absorption layer; 3. intelligent terminal, 4, metal contact, 5, magnetism piece of inhaling.

Detailed Description

In order to facilitate understanding of the present application, the technical solutions in the present application will be described more fully and in detail with reference to the drawings and the preferred embodiments, but the scope of protection of the present application is not limited to the following specific embodiments, and all other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

It will be understood that when an element is referred to as being "coupled" or "connected" to another element, it can be directly coupled, connected or communicated with the other element or indirectly coupled, connected or communicated with the other element via other intervening elements.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present application.

Examples

Referring to fig. 1, a PPG pulse wave simulator comprises a host 1, a human body simulation structure and an intelligent terminal 3, wherein the intelligent terminal 3 is in communication connection with the host 1 through a USB or BT, and the host 1 is electrically connected with the human body simulation structure. The human body simulation structure is designed based on the actual wearing position of a product to be detected, and the product to be detected in the embodiment is the smart watch 01, so that the human body simulation structure is specifically the simulated wrist 2. The intelligent terminal 3 can be a PC, a notebook, a tablet or a mobile phone, a control program runs on the intelligent terminal 3, the intelligent terminal is connected with the host 1 in a wired or wireless mode, commands are sent to the host 1 to control testing environment and parameters, the host 1 is used for driving the simulation wrist and controlling light path reflection conditions inside the simulation wrist 2 according to the commands to realize human body simulation. The intelligent watch 01 to be tested is worn on the simulated wrist 2, and the PPG test on the intelligent watch 01 is realized by observing the test parameters set on the intelligent terminal 3 and the display output of the intelligent watch 01.

Referring to fig. 2 to 4, the simulated wrist 2 includes a simulated main body 21 and a light incident window 22 disposed on the simulated main body 21, an optical structure formed by sequentially arranging a dimmer 24, a beam splitter 25, a liquid crystal light valve 26 and a reflector 27 along a light incident path is disposed in the light incident window 22, and a control circuit connected to the liquid crystal light valve 26 is disposed in the simulated main body 21.

The intelligent watch 01 is arranged at the light incidence window 22, and optical characteristics of a human body in different states are simulated by controlling the reflection degree of the optical structure. The liquid crystal light valve 26 and the reflector 27 simulate the optical properties of the pulsation of blood vessels, i.e., AC components, and the dimmer 24 and the spectroscope 25 simulate the optical properties of different skin colors, musculoskeletal tissues, etc., i.e., DC components.

Assuming incident light intensity as I₀The transmittance of the liquid crystal light valve 26 is B, and since the reflectivity of the selected reflector 27 is close to 100%, it can be considered that there is substantially no energy loss, so that after the light passes through the liquid crystal light valve 26 twice, the reflected light intensity I theoretically received is:

I＝I₀×B² (1)

of course, if the selected reflector has a non-negligible energy loss during the reflection process, and the reflectivity of the reflector is a, the reflected light intensity I is:

I＝I₀×B²×A

as can be seen from the formula (1), only the AC component and no DC component are contained in the reflected light obtained by the optical structure formed by the reflector 27 and the liquid crystal light valve 26, and as a result, the wrist of the human body cannot be simulated, so that the present application adds the beam splitter 25 to the light path.

Assuming that the splitting ratio of the beam splitter 25 is M/N (M + N equals to 100), i.e. M% of the light passes through the beam splitter, and N% of the light is reflected back by the beam splitter, the formula (1) can be expressed as (because the intensity is rapidly attenuated, the effect of multiple reflections is ignored):

I＝I₀×N％+I₀×M％²×B² (2)

by reasonably selecting the light splitting ratio, the ratio of DC to AC can be controlled, and the purpose of approaching the optical characteristic of the wrist of a human body is achieved.

The absorption of the skin with different complexion is different, and the absorption property is expressed as the attenuation of the light, therefore, in order to simulate the skin with different complexion, the light-reducing sheet 24 must be used to attenuate the incident light on the light path, assuming that the light transmission ratio of the light-reducing sheet 24 is K%, then the formula (3) can be expressed as:

I＝I₀×N％×K％+I₀×M％²×B²×K％ (3)

the attenuation rates of different skin colors to light are very different, and in order to simulate the wrist of a human body more precisely, different types of light reduction sheets must be used for different skin colors.

Because the interference of ambient light must be avoided in the simulation process, and the shading treatment must be done for the light path, therefore, an annular shading cover 23 is added at the entrance of the light incidence window 22; and a black light absorbing layer 28 is further provided around the optical structure, i.e., on the inner wall of the light incidence window 22, in order to eliminate the interference of light on the optical path.

In this embodiment, the light shield 23 is made of a high-density black sponge material, and is partially embedded in the annular groove at the light inlet end of the light incident window. The attenuation ratio of the dimmer 24 is 10-90%, and the coverage wavelength range is 400-1100 nm. The light splitting ratio of the light splitting sheet 25 is between 20/80 (transmission amount/reflection amount) and 80/20, and the coverage wavelength range is 400-1100 nm. The reflector plate 27 is made of a material with fixed reflectivity, the coverage wavelength range is 400-1100 nm, and the reflectivity is regarded as 100%.

The dimmer 24 and the sub-segments 25 need to be replaced due to the need to simulate different skin tones and the optical properties of the musculoskeletal structure. In other embodiments, the light incident window 22 and the simulation main body 21 may be detachably connected, or both the dimmer sheet 24 and the light splitter sheet 25 may be detachably connected to the light incident window 22, but in view of the fragility of the optical lens and the inconvenience of replacement, in this embodiment, the simulation wrist 2 and the main body 1 are detachably connected.

Specifically, a circular groove 11 for inserting a fixed human body simulation structure is arranged in the center of the host 1, and the diameter of the groove 11 is 1-5 mm larger than that of the insertion end of the simulation wrist 2, so that the simulation wrist 2 can be replaced conveniently. The connecting position of the groove 11 and the simulated wrist 2 is provided with a plurality of correspondingly connected metal contacts 4, wherein the metal contacts on the bottom surface of the groove 11 are four convex and elastic metal probes, the metal contacts on the bottom surface of the simulated wrist 2 are four metal sheet structures designed corresponding to the metal probes, and the metal probes and the gold structures can be in close contact due to the design of a concave-convex structure.

In this embodiment, in order to ensure the two when being convenient for carry out the dismouting to host computer 1 and emulation wrist 2 and stabilize when connecting, the connected mode design of emulation wrist 2 and host computer 1 is for magnetism to inhale formula isolating construction, set up the opposite permanent magnet of magnetic pole respectively in recess 11 bottom surface and emulation wrist 2 bottom surface promptly and inhale piece 5 as magnetism, according to the different grades of principle of inhaling of magnetic pole, when emulation wrist 2 and recess 11 are in certain extent, emulation wrist 2 can be adsorbed in recess 11 automatically and in close contact with. In other embodiments, a snap assembly may be used in place of the magnetic element.

In this embodiment, an indicator light for indicating whether the metal contact is normally contacted is further provided on the main body 1. When metal contact 4 normally contacts, the green light of host computer lights, otherwise then the red light of host computer lights, plays the effect of instructing the warning, and the simple operation has the fool-proof function, can realize the protection to the circuit.

The working process of the PPG pulse wave simulator in this embodiment is as follows:

step 1) starting a host 1, ensuring that the host 1 and an intelligent terminal 3 are normally communicated, and normally connecting the host 1 and a simulated wrist 2;

step 2) sending a command to the host 1 through the intelligent terminal 3, and controlling the transmittance and the change frequency of the liquid crystal light valve 27 after the host 1 receives the relevant command to perform pulse simulation;

step 3) correctly placing the intelligent watch on the simulated wrist 2, enabling the emitted light to be aligned with the light incident window 22, starting the intelligent watch to work and measuring the pulse rate value according to a certain standard;

step 4) comparing the pulse rate value simulated by the host with the pulse rate value finally measured by the intelligent watch, and if the difference value between the pulse rate value simulated by the host and the pulse rate value finally measured by the intelligent watch meets the detection standard, detecting the PPG index of the intelligent watch to be qualified;

and 5) replacing different simulated wrists according to the requirement, or superposing simulated data such as light interference, motion artifact, baseline drift and the like in the data to simulate the real situation.

The above description is only a few examples of the present application and does not limit the scope of the claims of the present application, and it will be apparent to those skilled in the art that various modifications and variations can be made in the present application. Any improvement or equivalent replacement directly or indirectly applicable to other related technical fields within the spirit and principle of the present application by using the contents of the specification and the drawings of the present application shall be included in the protection scope of the present application.