Hello pro, the heartbeat does not show, because in the exercise, the state of the wearable device in the wrist, will produce shaking, thus affecting the quality of the heart rate measurement signal, different types of sports, the movement produces a different noise signal. By selecting the appropriate type of exercise, the algorithm can be better targeted for processing, improving signal quality and ensuring more accurate heart rate measurement. Therefore, it is recommended that you choose the correct type of exercise when you start exercising in order to obtain more accurate heart rate data during exercise. During exercise, you may sweat a lot, the wearer slides the device up and down, and the sweat covers the heart rate monitoring sensor, which may cause the heart rate measurement to deviate. Please dry the sweat on your wrist and the device, keep the back of the device clean and dry, and put it back on tightly after it is not covered by foreign objects. The pressure value is not displayed, you can open the health monitoring on the device page of Huawei Sports Health App and turn on the pressure auto-detection switch. When you use it for the first time, please perform pressure calibration in Huawei Sports Health App and fill out the pressure calibration questionnaire. The bracelet/watch does not provide pressure data during the exercise state. When you stay quiet for a long time, the bracelet/watch automatically performs pressure detection.
How to measure heart rate on Xiaomi bracelet? Why does it always show failure?
According to the following operation you can measure heart rate, there are several reasons for failure, see below.
The correct way to wear the Xiaomi bracelet:
1. The wearer needs to wear the appropriate tightness, around the wrist area, wear too loose or wear too tight can not accurately measure the heart rate.
2. After wearing, touch the Xiaomi bracelet 2 button to enter the heart rate measurement, please keep still during the measurement, the heart shape on the screen of the bracelet flashes, indicating that it is measuring.
3. Wait for a few moments, the measurement results will appear on the Xiaomi MiBand 2 display.
Reasons for failure to measure heart rate:
1. Xiaomi's products always come with a cost-effective label, including the Xiaomi bracelet 2 which is now on sale, and this bracelet realizes most of the functions that were not available in the first generation of the bracelet, such as time display, step view, heart rate monitoring, sleep monitoring and so on.
2. It may be that the user's wrist and body are in motion when testing heart rate changes, a situation that could easily lead to changes in the bracelet's detection range, resulting in unrecognizable situations.
References
uc headline. uc headline [cited 2018-1-24]
Computer Pepsi. Computer Pepsi.com[cited 2018-1-24]
Smart bracelet to measure heart rate and blood pressure quasi
Principle of the smart bracelet to measure heart rate and blood pressure
Generally speaking, the principle of heart rate monitoring is usually divided into three kinds of: one is the photoelectric transmittance measurement, which is in principle that the sensor of the bracelet in contact with the skin will emit a beam of light hitting the skin, and the measurement of the reflected/ transmitted light. Because blood absorbs a specific wavelength of light, each time the heart pumps, that wavelength is absorbed in large quantities, and the heartbeat can be determined in this way. However, the disadvantage is that it consumes a lot of power and can be disturbed by ambient light. Most of the smart bracelets or watches on the market today that monitor heart rate use the photoelectric transmission measurement method.
There is another way to test the ECG signal method, the sensor of the bracelet can determine the user's heart rate by measuring the electrical signal of the contraction of the heart muscle, the principle is similar to the principle of ECG. The disadvantage is that the circuit is more complex, occupies more PCB space, is susceptible to electromagnetic interference, while the sensor must be close to the skin, placed in a relatively fixed position, so it is difficult to have a bracelet to use this measurement method.
On top of that, there's vibration measurement, which has only recently come out. Because each heartbeat causes the body to vibrate, through a high-precision . Sensors capture this vibration, and then after signal processing can get the heartbeat, in general, intelligent cushion or intelligent massager products will mostly use this measurement method, the bracelet is less common.
How accurate is the heart rate bracelet
Accuracy, in fact, I've already mentioned, most of the bracelet photoelectric transmittance measurement method is not very accurate, it is easy to be disturbed by the external environment, for the individual, the importance of the bracelet heart rate monitoring in fact, can be continuously monitored, even if the absolute value is not allowed, but the relative trend of changes in analyzing the The newest addition to the list is the newest addition to the list, the newest addition to the list, the newest addition to the list.
Whether the bracelet can do real-time dynamic ECG measurement
The single-handed bracelet can't measure ECG because the simplest single-conductance ECG requires at least one electrode to be placed on each side of the body. Of course, technically speaking, an ECG bracelet is perfectly feasible, but it would probably require the user to wear one on both the left and right hand. In fact, from life, we don't need to see our own ECG in real time at all, and being able to see the state of change in our heart rate over time is enough.
Can measure the heart rate of the bracelet worth it
With the rise of smart wearable devices, more and more manufacturers to join the smart wearable market in the melee, the first to carry out is the price war, the threshold of the bracelet is low, naturally, it will attract a part of the user's attention, in the face of some of less than one hundred dollars to test the heart rate of the product, I believe that many friends of the first reaction is so cheap, in the end, it is not reliable, in the end, it is worth it, it is worth it. In the end, reliable or not, in the end worth buying.
On the question of reliability, as I mentioned before, the bracelet to measure the heart rate, itself is not very accurate, the significance of which is only to allow people to understand the trend of their own state, and many bracelets are also just the utility to do so, there is not much extension. So if you really want to discuss whether it's worth buying, I think, if you simply want to experience, or want to use it as a toy, spend a low price to buy one to play with or can, if you really expect it can assist you to treat or prevent disease, that or forget it.
From the current stage, even though the future of the smart bracelet is bright, but I have to say that the emergence of the heart rate monitoring function, its gimmick is far greater than the actual utility, in plain English, the average user knows their own heart rate status of the use of it? They don't have a doctor on their side to provide real-time advice, and the bracelet often doesn't provide users with some constructive guidance, looking at the heart rate on the phone, what we can know is probably just a set of numbers, and a status chart.
In fact, smart bracelet manufacturers should pay more attention to the ecosystem, if the smart bracelet's APP can integrate some medical platforms, such as customized private doctors and so on, then it is also considered to be the people's move, I believe there will be a lot of people for the bill, but unfortunately, to do this, it should cost a lot of resources, the implementation of the real should also have to wait for a long time. Of course, I'm just offering an idea. What do you expect from a smart device that assists with your health?
Smart bracelet to measure heart rate scam
Smart bracelet to measure heart rate scam
Smart bracelet to measure heart rate scam, smart bracelet is a kind of wearable smart device, most of the smart bracelet on the market, are mainly to detect the heart rate, so a lot of people in the exercise will choose to wear a smart bracelet, in order to better detect their own exercise, in order to come down to understand the smart bracelet to measure heart rate scam.
Smart bracelet heart rate scam 1
How smart bracelets work
Early sports bracelets were equipped with only a simple accelerometer sensor and Bluetooth functionality, so it only functioned as a simple pedometer, which was then connected to a smartphone to check the amount of exercise through an app on the smartphone.
Later, with the development of technology, smart bracelets with mobile apps can realize more complex applications - monitoring heart rate, sleep, sports status assessment and a series of health-related functions.
In particular, with the advent of heart rate monitoring, fitness professionals can know the changes in their heart rate at any time during the running process, so as to scientifically adjust their fitness rhythm.
If you find the business marketing bracelet in addition to the above heart rate, exercise and other monitoring functions there are some other outrageous features, just run, proper IQ tax.
How does a smart bracelet detect our heart rate
Smart watches and smart bracelets commonly found in our daily lives generally use the PPG (photoelectric volumetric pulse wave recording) method to monitor heart rate and blood oxygen.
This is a photoelectric detection method, which first uses LED light source to generate light pulses and shoot them into human skin tissues at a certain angle, and then the photosensitive element at the receiving end converts the light signals reflected from the skin into electrical signals, and then obtains the value of the heart rate after certain signal processing.
Because the blood in our skin tissues changes periodically with the pulse, their absorption of incident light also changes periodically with the pulse, so the strength of the photoelectric signal received by the receiving end of the smart bracelet changes with the pulse. Through digital signal processing algorithms, we can then calculate the pulse period from this, and thus the heart rate.
But this method is not foolproof.
For example, many people find that their heart rate is only 80% after a high-intensity workout, and this is mainly because the position of the photocells and the degree to which they are attached to the skin changes with the body's activity, which can lead to inaccurate pulse rate measurements.
Then again, when someone puts a sports bracelet on a paper towel, it actually measures heart rate! Why is this? It's actually the smart bracelet's inability to recognize whether or not what it's monitoring is a living organism.
It defaults to this being your wrist when it touches the tissue, and then it gets to work: emitting a beam of light - collecting the reflected information - and algorithmic processing. So even if the tissue doesn't have a heartbeat, when the transmitter emits green light and puts it on the surface of the tissue, there's still a light reflection, and what you end up with is the result that the receiver receives after the light is reflected off the surface of the tissue.
However, I believe that as technology advances, smart wearable devices will also continue to progress, smart wearable devices can detect the body parameters will gradually increase, so as to provide more and more accurate information for the monitoring of our physical health status.
It is important to point out that the brand and price differences between smart bracelets and smart watches are very large, and the accuracy of heart rate testing and sleep quality monitoring of different wearable devices varies greatly, and at present, most of the smart bracelets estimate the values of these physiological parameters through digital algorithms, and there is still a large gap between their accuracy and that of the professional devices, so people who have health problems or have higher requirements for the accuracy of pulse and blood pressure data are still recommended to use the professional devices. So people who have health problems or have higher requirements for the accuracy of pulse and blood pressure data are still recommended to use professional medical devices for measurement.
Additionally, a smart bracelet is only a tool for those who want to use it. A small bracelet can greatly facilitate our lives, but we still need to choose the right product according to our own needs.
Smart bracelet heart rate scam 2
One, smart bracelet heart rate in the end is not reliable? Let the industry experts for you to reveal the secret
The first: PPG photoelectric volumetric pulse wave tracing method principle (PhotoPlethysmoGraphy)
Simply put, the reflection is just, is the use of blood transmittance of pulsation changes, converted into electrical signals, corresponding to is the heart rate.
▲Representative product: FitbitchargeHRSurge
When a certain wavelength light beam irradiated to the surface of the skin at the end of the finger, the light beam will be transmitted to the photoelectric receiver through the transmission or reflection, in the process due to the finger, the end of the skin and muscle and the absorption of blood attenuation, the detector detected by the intensity of the light will be weakened. The absorption of light by the skin and muscle tissue remains constant throughout the blood circulation, while the volume of blood within the skin is subject to pulsatile changes under the action of the heart.
When the heart contraction peripheral blood volume is the most light absorption is also the largest, the detected light intensity is the smallest. When the heart is in diastole, the opposite is true, the detected light intensity is the greatest, so that the intensity of light received by the optical receiver is then pulsating changes.
Why do we often see green LEDs?
Because in the presence of a red liquid such as blood, the absorption of green light is the greatest, and it is more accurate for data judgment.
When the user's heart beats, more blood flows through the user's wrist, and the more green light is absorbed. In between heartbeats, blood flow decreases, resulting in less absorption of green light as well.
As an example, suppose the luminous value of the bracelet is 100, the skin muscle tissue absorbs a constant 10, and the total blood absorption is 15, then after reflection it is 100-10*2-15=65, then the arterial blood comes over, the red blood cells contain more oxygen, and the total blood absorption becomes 2 being, then after reflection it is 50, and after that it will be always in 65-50-65-50-65-50-65-50- 65-50-65-50, and by counting how many pulse changes per second, you get your heart rate.
I don't know if PPG reads this way?
It's principle then determines its drawbacks, what if there is a lot of sweat directly between the bracelet and your skin? Then the values would be inaccurate.
If your values change like this, 65-50-65-50-65-50-66-51-62-50-65, etc., this will also blind the machine.
In summary:
This method, the measurement of resting pulse and normal regular movement (running, etc.) is still relatively accurate, but for irregular sports, such as soccer and badminton and other irregular sports, for example, said that the assumption that the value will pop up, it will be a slight decrease in accuracy. But it's also a difference of a few values, for non-professionals, I feel it should be enough.
The second type: ECG signal measurement, similar to the ECG (electrocardiogram)
This is a little simpler to say, that is, you go to the hospital to do the electrocardiogram, in fact, a little similar. The difference is that hospitals need to add electrodes to the heart, feet, and wrists, and need to measure more data, while wrist watches don't need so much data, just the heart rate is enough.
Simply put:
The tissues and bodily fluids around the heart can conduct electricity, so the human body can be viewed as a volume conductor with a length, width and thickness of three degrees of space. The heart is analogous to a power source, and the sum of action potential changes in countless cardiomyocytes can be conducted and reflected to the body surface. There are potential differences between many points on the body surface, and there are also many points that are isoelectric without potential differences between each other. Through the collected electrode changes, processed by algorithms, many values can be reduced, among which the heart rate value can be reduced.
Every time the heart beats, there are tiny electrode changes on the surface of the human body, and capturing these electrode changes and then going through the algorithm can restore the 'frequency' of the heart rate beats. As far as I know, within the bracelet, it seems like jawbongUP3 uses ECG measurement technology, and most of the others are optoelectronic.
As an emerging product of the 21st century - smart wearable products, because of its specific use scenarios and wearing requirements, applied in the field of heart rate monitoring technology is currently the main photoelectric volumetric pulse wave tracing method, referred to as photoelectric method, ECG signal method, pressure oscillation method, image signal analysis method and other categories.
As for the heart rate belt, generally also use the cardiac measurement, detection of body surface electrode changes, restore the heart rate value.
Two, heart rate monitoring and how to realize?
1, photoelectric method
Simply put, this method of measuring heart rate is based on the principle of absorption of light by the material, through the smart wearable device with the green LED light photoelectric diode irradiation blood vessels for a period of time, because the blood is red, it can reflect the red light to absorb and receive green light, in the heart beat, the blood flow increases, the amount of green light absorption will be bigger; in the intervals between the heart beat blood flow increases, the amount of green light absorption; in the When the heart beats, the blood flow increases, the absorption of green light will be greater; in the intervals between heart beats the blood flow will decrease, and the absorption of green light will also decrease. Therefore, heart rate can be measured based on the absorbance of blood.
Specifically, when a certain wavelength light beam irradiates the skin surface, the light beam will be transmitted to the photoelectric receiver by transmission or reflection, and the intensity of the light monitored by the detector will be weakened due to the attenuation of the absorption by the skin muscle and blood in the process. The human body's skin, bones, flesh, fat and other light reflection is a fixed value, while the capillaries and arteries and veins in the role of the heart with the pulse volume keeps getting bigger and smaller.
When the heart is contracting, the peripheral blood volume is the largest, the light absorption is also the largest, the detected light intensity is the smallest; and in the heart diastole, just the opposite, the detected light intensity is the largest, so that the light intensity received by the light receiver is then a pulsating change.
Most smartwatches use the photoelectric method to monitor heart rate, and their distinctive feature is a green LED light at the sensor site.
There are many types of photoelectric sensors that use this measurement principle, and depending on where the light signal is received, the photoelectric method can be categorized into two modes: transmission and reflection.
1. Transmission photoelectricity
Transmission photoelectricity refers to wearable devices on the generator (emitter) and photosensitive receiver (detector) is located on both sides of the measured part (usually fixed by a clip), the incident light through the skin into the deep tissues, in addition to being absorbed by the skin, muscles, blood, bones, etc., the remaining part of the light transmission by the photoreceptors. According to its principle, this method is applicable to the measurement part of the human body on both sides of the relatively short distance between the tissues, such as earlobes, fingers, toes, etc., and the representative smart wearable products are those ear-clip heart rate monitors, fingernail oximeters and so on.
Smart wearable products that use the transmissive photoelectric method are usually secured with a clip.
The products of this monitoring method usually take the structure of sealed dark box in appearance, which can well reduce the exogenous light interference, thus improving the measurement accuracy and stability. Due to its high signal-to-noise ratio and stable signal, in addition to measuring heart rate, it can also analyze heartbeat function, blood flow and many other cardiovascular physiological information through waveforms. The disadvantage is that it is not suitable to be applied to smart bracelets and smart watches, while products applied to earlobes, toes and other parts of the body will be uncomfortable to wear.
2. Reflective photoelectricity
In contrast to the transmissive photoelectricity method, in the reflective photoelectricity method, the generator (emitter) and the photosensitive receiver (detector) on the wearable device are located on the same side of the measured area, and the reflected light is mainly measured. The advantage of this method of measuring heart rate is that it is very simple and requires very little measurement area, as long as the tissue is relatively smooth and there is little subcutaneous fat can be measured almost anywhere, such as the forehead, wrist.
Thus, most smart bracelets, smart watches, and other wearable devices use this method to measure heart rate. Moreover, appearing in the form of smart bracelets or smartwatches as products also perfectly solves the dual requirements of heart rate monitoring by the transmission photoelectric method and wearing comfort.
However, although the reflective photoelectric method performs well in steady state, when the device is worn on the end of the wrist, it will swing up and down like a pendulum as the user walks or moves erratically, and the centrifugal force will cause the blood volume to change drastically; when the vasoconstrictive pressure and the centrifugal force interact with each other in the bloodstream, it will be more difficult to discern the amount of blood in the blood vessels. Thus the accuracy of heart rate data may be reduced. In addition, the looseness or tightness with which the wearable device is worn and the amount of blood flow through the body's skin can also affect monitoring accuracy.
2. ECG Signal Method
The ECG signal method is actually the most accurate method of measuring heart rate commonly used at the medical level. In each cardiac cycle, the heart is excited by the pacing point, atria and ventricles successively, accompanied by countless cardiomyocyte action potential changes, these bioelectric changes are called electrocardiograms (ECG), and heart rate can be detected through the cyclic changes of ECG. In addition to heart rate, ECG can also provide information including cardiac dysfunction, cardiac disease, and recovery of cardiac function, and the patient's physical and psychological stress.
For smart wearable devices, the sensor can measure the electrical signals from the contraction of the heart muscle to determine the user's heart rate, the principle is similar to the ECG, the accuracy of this method is very high, but the disadvantage is that the circuit is more complex, accounting for PCB space is relatively large, and susceptible to electromagnetic interference, and at the same time, the sensor must be close to the skin, the placement of the location of the relatively fixed, so the use of this measurement method is not common in smart wearable products. The smart wearable products that use this measurement method are not common.
The ECG lead system.
3, pressure oscillation method and image signal analysis method
Pressure oscillation method is mainly used in electronic sphygmomanometer, sphygmomanometer cuff to arm pressure, through the thin film pressure sensor to detect the amplitude of arterial vascular pulsation for AD conversion, so as to measure the blood pressure and pulse rate (according to a certain period of time, how many pulse waves to calculate the heart rate). The image signal analysis method mainly uses face images to estimate heart rate.
Because the color of a person's face changes slightly when the heart beats, and because there are subtle movements of the chest and shoulders, the captured images can be used to estimate heart rate and respiratory rate.
The Massachusetts Institute of Technology launched the Vital-Radio is issued by the router Wi-Fi signals, when the signal encounters the surrounding people or objects will immediately rebound, through a special algorithm can be calculated each time the signal reflection speed, in order to determine the presence of life objects, if it is a life form, this product will record the human heart rate and respiratory rate.
These two methods are more demanding on the user, and are limited to situations where the human body is relatively stationary, and the results will be much worse if the method is not appropriate, and even less accurate for patients suffering from certain cardiovascular diseases. As a result, there are very few products in the smart wearables space that use these two methods to measure heart rate.
Smart bracelet heart rate measurement scam 3
Smart bracelet can also measure blood pressure? Is it reliable?
Now many smart bracelets have the function of blood pressure measurement, but this so-called measurement of blood pressure is only a rough estimate, not the real pressure on the walls of human blood vessels (i.e., blood pressure), so compared with the advertised function of detecting heart rate, the detection function of blood pressure, may be a little inferior.
Is real-time sleep monitoring reliable? Sleep detection is also an important advantage of the smart bracelet, through the bracelet internal sensors, sensing the skin, when a person is asleep, do a movement, posture, sleep time, amplitude, to analyze the deep sleep and light sleep, and then based on the data to produce results.
For example, many smart bracelets monitor sleep by actually analyzing whether your smart bracelet moves with time, size, and frequency. For example, if you're lying still, after a long period of time, your smart bracelet may default to you being asleep, when in fact you're not at that moment.
There used to be smart bracelets where you had to press the sleep button when you realized you were going to fall asleep, and then go back to sleep. Many people were probably already too sleepy to stand. But after pressing the sleep button, they immediately woke up and couldn't fall asleep instead. From this point of view, the smart bracelet is not so "smart".
Is a smart bracelet a medical device? Since the main concern is physical health, many people ask whether smart bracelets are medical devices. After all, the state's approval and management of medical devices is quite strict. If a particular smart bracelet is an approved medical device, then it can be purchased with confidence!
In fact, after the fact, the current smart bracelet measurement of heart rate is still very reliable, and the error is not too big. Although the detected data is for reference only and cannot be used as a basis for diagnosis, it does not affect the accuracy of the smart bracelet. Therefore, if you or your family, more concerned about the heart, heart rate, then it may be possible to buy a smart bracelet to detect, will also be a good choice.
Smart bracelets, watches and other wearable devices will generally have a heart rate detection function, used to monitor the state of human health, spit over the millet bracelet 4 measured heart rate is not allowed error is relatively large how is it?
Millet bracelet 4 heart rate error?
1, please ensure that the back of the bracelet is clean, dry, and no foreign objects cover. Excessive sweating during exercise causes the watch to slide, and sweat obscures the light path, which may lead to inaccurate heart rate measurement. Please dry the sweat and put it on again.
2. It is recommended to use a soft rubber strap so that the device fits better to your wrist and the monitored data is more accurate.
3, the human heart rate is not stable and immobile, even in a stationary state, the heart rate data will have a small range of fluctuations, and after strenuous exercise continuous measurement of a single heart rate, the heart rate value will be jumped larger, this is due to the human body's own heart rate of the rapid decline of the body caused by the phenomenon of a normal phenomenon. When you stand, sit, eat, drink, etc., the range of heart rate data changes will also increase accordingly.
4, regular exercise (such as running, walking, cycling, etc.) is easier to measure the heart rate, non-regular exercise (such as playing ball, free activities) may not be able to measure the heart rate, wrist strength type of exercise (such as weight lifting) may not be able to measure the heart rate.
5, may also be caused by hardware failure, recommended before and after the millet service center testing and troubleshooting.
This article applies to millet bracelet 4 as an example