Smart rings use a variety of sensors and algorithms to differentiate between sleeping and waking states, and here are the main ways they do it:
Sensor monitoring
Accelerometer: monitors the movement of the finger. When the user is at rest or has only slight movements such as rolling over or breathing, the smart ring will determine that the user is in a sleeping state; and when a large amplitude or frequency of finger movement is detected, the user is considered to be in a waking state
Heart Rate Sensor (PPG Sensor): Aids judgment by monitoring changes in heart rate. During sleep, the heart rate usually decreases and remains relatively stable, while when waking up, the heart rate will increase.
Body Temperature Sensor (BTS): Measures the skin temperature of the fingers. During sleep, the body temperature decreases, while upon awakening, the body temperature may increase.
Algorithm Analysis
Motion Pattern Recognition: The smart ring's algorithm will analyze the finger's motion patterns, such as rolling over, limb twitching, etc., and combine the changes in these motion patterns to determine whether the user is in the sleeping or waking state
Heart Rate Variability (HRV) Analysis: HRV refers to small changes in heart rate, which can reflect the body's autonomic activity. HRV is usually higher during sleep and lower when waking up. The smart ring aids in determining the user's sleep status by analyzing changes in HRV
Comprehensive Data Judgment
The smart ring will synthesize and analyze the data collected from accelerometers, heart rate sensors and body temperature sensors, etc., and process the data through an algorithmic model to ultimately determine whether the user is in a sleeping or waking state.
For example, when the accelerometer detects that the finger is stationary, the heart rate sensor shows that the heart rate is decreasing and stable, and the body temperature sensor shows that the body temperature is decreasing, the smart ring will synthesize this information to determine whether the user is in a sleeping state; on the contrary, when the finger has obvious movement, the heart rate is increasing, and the body temperature is increasing, then the user is in a waking state.
