How smart watches work

How smart watches work

Sports, body care and health are in trend. But how to follow the work of your body, if you are not on a treadmill in the gym, which shows how many kilometers you have passed and how your pulse changed at that time? How to determine how many calories you lost while going to work or running around the store? This will help smart watches or fitness bracelets, which not only count the pulse and the number of steps, but also are able to determine the phase of sleep, and also have the function of a smart alarm clock. How does all this functionality work and fit in a small bracelet? We will tell about it today.

Keep abreast

Many people ask themselves: why count the pulse? This is necessary in order to determine the intensity of physical exertion, as well as to warn a person about at what point the activity should be reduced.

The pulse can be calculated simply by placing a hand on the wrist or the carotid artery - in those places where the vessels are located closer to the skin surface. But this method of determining the heart rate is not too accurate and inconvenient. Well, who will measure the pulse in this way during the morning run? Another thing is a fitness bracelet: it measures the heart rate very accurately and at the same time it works constantly, showing the measurement results on the display.

Fitness bracelets that are now popular work on LEDs and photo detectors located on the back of the bracelet. This method of measuring the pulse is also called optical plethysmography. How it works? Everything is very simple. During the outflow of blood, the area of ​​the vessel decreases, the skin in this place becomes lighter and reflects more light emitted by the LED. When the vessel is again filled with blood, it increases, the skin, respectively, darkens and the amount of light reflected by it becomes smaller. The LED is very small and spends very little energy, making fitness trackers an excellent alternative to more complex and cumbersome heart rate monitors.

Step and believe

It would be completely ridiculous to count your steps on your own. Of course, for this it is better to use a pedometer, and even better - a fitness bracelet, which has the function of counting steps and distance traveled. This works thanks to an accelerometer that captures acceleration in different directions. During the movement of the body when the foot contacts the ground, the mass of the accelerometer changes its position. This resembles the work of a pendulum, the movements of which are recorded by the sensor and are displayed on the screen in a quantitative form.

In modern fitness trackers, complex algorithms for calculating steps are used to eliminate erroneous triggers when performing daily activities that have nothing to do with walking, for example, when washing floors or when traveling by car.

A smart bracelet with the function of a pedometer every day will not only inform you about the number of steps, but also show how much distance was covered, how many minutes or hours activity continued, how many calories were spent and how many liters of gasoline were saved.

Watching how we sleep

A person’s sleep consists of duplicate cycles of the phases of deep and superficial sleep. During deep sleep, the brain is at rest and this helps a person to restore his emotional background and physical strength. Superficial sleep on the contrary activates brain processes and helps to remember and organize all the information received during the day. So why analyze sleep and how does a smart watch do it?

The fitness bracelet identifies and analyzes sleep phases using special sensors and algorithms:

 - Sound sensor - records and analyzes the sounds made by a person during sleep. In the superficial sleep phase, there are much more;

 - Accelerometer - captures all movements of a person in a dream. Deep sleep, in contrast to the surface, is accompanied by a minimum amount of motor activity;

 - Pulsometer - monitors the work of the heart of the sleeper. During the transition from the deep phase to the superficial sleep phase, the pulse is accelerated.

Determining the phase of sleep is necessary in order to calculate the most appropriate time to wake up. It should occur in the phase of superficial sleep, so that a person wakes up in a vigorous state and good mood. The tracker itself determines the time interval when the user is ready to wake up, and wakes him up with a slight vibration on the wrist.

Fitness bracelet will tell not only about the duration, but also about the quality of sleep. It records the presence or absence of snoring and talking in a dream, and also determines the amount of carbon dioxide and the temperature level in the room.

We believe that we spend and that we eat

It is very important for people who monitor their health and body to know how many calories they have spent. Smart watches perform this calculation using a programmed algorithm that takes into account the number of steps taken and the distance traveled.

But no less important is the calculation of calories consumed. To do this, some fitness bracelets are equipped with a function called “food diary” In order to carry it on, it is enough to scan the barcodes of food products, and the program will calculate the number of calories it contains.

Any smart watches work in tandem with a smartphone, and on its screen you can see graphs of calories consumed and consumed, as well as information about the balance of fats, proteins and carbohydrates in the diet.

As you can see, each fitness tracker has sensors and special software in order to provide the user with the most complete information about the state of his body. With this gadget you can watch yourself throughout the day and be aware of even small changes in the body. Sometimes such a small, but such a useful device can indicate the presence of health problems and even save lives by fixing the malfunction of the user's heart rate. That is why this watch is needed for every person who cares about his health, fights for a good quality of sleep and monitors his diet and figure.