Human skin wearing recognition system based on various sensors

Abstract

The invention relates to the technical field of sensor recognition, and discloses a human skin wearing recognition system based on multiple sensors, which comprises an optical sensor, an acceleration sensor, a capacitive sensor and a central micro-control unit, the optical sensor is used for detecting skin reflection signals; the capacitance sensor is used for detecting skin capacitance induction; the acceleration sensor is used for detecting static and action; and the central micro-control unit receives the three signals and judges that the current equipment is worn on a human skin or non-skin object. According to the invention, the optical sensor and the capacitive sensor are adopted for wearing identification at the same time, the optical sensor and the capacitive sensor can complement the defects of each other, high-precision identification can be realized when the wearing equipment is in a moving state and a static state, and the wearing identification coverage scene is richer.

Description

Technical Field

[0001] The present invention relates to the field of sensor identification technology, and in particular to a human skin wearing identification system based on multiple sensors. Background Art

[0002] Smart wearable devices are portable devices, including smart watches, headphones, and AR / VR products. They realize their functions through software support and cloud interaction technologies, and are widely used in entertainment, sports, and medical health. In recent years, with the improvement of residents' income levels, people have an increasing demand for portable, intelligent, and functionally integrated electronic products. Combined with the rapid development of wireless technology, cloud computing, and AI, smart wearable devices have entered a period of rapid development. Various sensors have been well applied in wearable devices, and the market continues to improve.

[0003] As the smartwatch ecosystem matures, most of them are equipped with optical chips to detect human health indicators, such as heart rate, blood oxygen, and pressure index. For the detection of these physiological indicators, it is necessary to first determine whether the watch is worn on human skin. As long as the optical sensor has a reflective surface, it will generate an optical signal, which will be transmitted to the algorithm to calculate the physiological indicator results. The traditional single optical sensor obtains the pulse signal of the capillaries in the human skin through photoelectric volumetric pulse wave recording, thereby determining whether the human skin is worn. However, the optical signal is severely disturbed by movement in a moving state. This method can only be recognized in a static state, and the recognition speed is slow, usually requiring 4-6 seconds, and there are many requirements for wearing tightness, skin color, and stability. A single capacitive sensor determines whether the human skin is worn through capacitive sensing. Since the capacitive sensor identifies the conductor, it cannot accurately distinguish between the skin and other conductors. Before the first use of the capacitive sensor, it needs to be calibrated under the condition that no object is close to the sensing area. The single capacitive sensor cannot determine whether the calibration conditions are met before being calibrated, so its use is limited. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art and to propose a human skin wearing recognition system based on multiple sensors.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A human skin-worn identification system based on multiple sensors, including optical sensors, acceleration sensors, capacitive sensors and a central micro-control unit;

[0007] Optical sensors are used to detect skin reflection signals;

[0008] Capacitive sensors are used to detect skin capacitance sensing;

[0009] Accelerometers are used to detect stillness and motion;

[0010] The central micro control unit receives the three signals and determines whether the device is currently worn on human skin or a non-skin object.

[0011] Preferably, the optical sensor includes a transmitting module, a receiving module and a first signal processing module. The transmitting module drives the LED to emit light, which is irradiated onto the skin. The reflected light is sensed as photocurrent by the receiving module, which is converted into a digital signal by the first signal processing module and then sent to the central micro control unit.

[0012] Preferably, the LED driven by the transmitting module adopts green light and infrared light.

[0013] Preferably, the capacitive sensor comprises a sensing electrode and a second signal processing module. The sensing electrode senses the conductor and converts the signal into a digital signal through the second signal processing module and then sends the digital signal to the central micro control unit.

[0014] Preferably, the sensing electrodes are arranged around a transmitting module of the optical sensor and are close to the transmitting module.

[0015] Preferably, the area of ​​the sensing electrode is greater than 20 square millimeters.

[0016] Preferably, the central micro control unit receives the signal from the optical sensor, calculates the spectrum energy of the human pulse signal by spectrum integration, and calculates the signal-to-noise ratio with other noise signals, thereby determining whether it is a human skin reflection signal.

[0017] Preferably, the central micro control unit receives the acceleration signal of the acceleration sensor, determines whether the current state is static or moving through the acceleration changes of the three axes, and determines the light signal of the optical sensor only in the static state.

[0018] A human skin wearing recognition method based on multiple sensors is applied to a human skin wearing recognition system based on multiple sensors, comprising the following steps:

[0019] The central microcontroller receives the acceleration signal from the acceleration sensor and determines whether the wearable device is currently in a stationary state or in motion through the acceleration changes of the three axes;

[0020] When in a stationary state, capacitive sensing is used first to determine whether there is capacitive sensing. If capacitive sensing is detected, optical sensors are used to determine whether the sensing signal comes from human skin or other conductive objects.

[0021] When in motion, use the capacitive sensor to determine the wearing status;

[0022] The capacitive sensor and the optical sensor are both in a normally closed state. After the acceleration sensor detects that the wearable device is switched from a static state to a motion state, the capacitive sensor is turned on, which is beneficial for saving power consumption in a non-motion state.

[0023] After the acceleration sensor detects that the wearable device is converted from a moving state to a stationary state, the capacitive sensor detects the skin capacitance induction, and if the condition that the conductor is approaching is met, the optical sensor is turned on, thereby saving the driving power consumption of the optical sensor transmitting module;

[0024] When the wearing state is output, if it is in the wearing state and the state is static at this time, the capacitive sensor and the optical sensor are turned off to save power consumption.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention uses both optical sensors and capacitive sensors for wearing recognition. The optical sensors and capacitive sensors can complement each other's deficiencies, and can achieve high-precision recognition in both the motion and static states of the wearable device, making the wearing recognition coverage richer.

[0027] 2. The present invention uses an acceleration sensor for detection, and after determining the wearing state and keeping still, the capacitive sensor and the optical sensor can be turned off, thereby saving power consumption;

[0028] 3. Optical sensors need to collect a section of skin reflected light signals before they can recognize the wearer, but capacitive sensors only need to sense the skin approaching to recognize it, and the recognition speed is faster. At the same time, when the capacitive sensor cannot distinguish between skin and other conductors, the optical sensor can cover such scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a flow chart of a human skin wearing identification method based on multiple sensors proposed by the present invention;

[0030] Figure 2 This is a schematic diagram of the composition of a human skin wearing recognition system based on multiple sensors proposed by the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0032] Reference Figure 1 and Figure 2 , a human skin-worn recognition system based on multiple sensors, including optical sensors, acceleration sensors, capacitive sensors and a central micro-control unit;

[0033] Optical sensors are used to detect skin reflection signals;

[0034] Capacitive sensors are used to detect skin capacitance sensing;

[0035] Accelerometers are used to detect stillness and motion;

[0036] The central micro control unit receives the three signals and determines whether the device is currently worn on human skin or a non-skin object.

[0037] In this embodiment, the optical sensor includes a transmitting module, a receiving module and a first signal processing module. The transmitting module drives the LED to emit light, which is irradiated onto the skin. The reflected light is sensed as photocurrent by the receiving module, which is converted into a digital signal by the first signal processing module and then sent to the central micro control unit.

[0038] In this embodiment, the LED driven by the transmitting module uses green light and infrared light. Since infrared light is invisible to the naked eye, it is used for continuous detection of wear without being observed. Green light is more suitable for detecting pulse signals. After the infrared light detects the approach of an object, the green light is used to detect whether the approaching object is human skin or other objects.

[0039] In this embodiment, the capacitive sensor includes a sensing electrode and a second signal processing module. The sensing electrode senses the conductor and converts the signal into a digital signal through the second signal processing module and then sends the digital signal to the central micro control unit.

[0040] In this embodiment, before the capacitive sensor is used for the first time, it needs to be calibrated under the condition that no object is close to the sensing area. Whether the calibration condition is met is determined by the optical sensor through the reflected light signal.

[0041] In this embodiment, the sensing electrodes are arranged around the transmitting module of the optical sensor and are close to the transmitting module to ensure that the sensing electrodes and the optical sensor detect the same area as much as possible.

[0042] In this embodiment, the area of ​​the sensing electrode is greater than 20 square millimeters to ensure that the signal intensity sensed by the electrode is sufficient to cope with environmental changes such as temperature drift.

[0043] In this embodiment, the central micro control unit receives the signal from the optical sensor, calculates the spectrum energy of the human pulse signal by spectrum integration, and calculates the signal-to-noise ratio with other noise signals, thereby determining whether it is a human skin reflection signal.

[0044] In this embodiment, the central micro control unit receives the acceleration signal of the acceleration sensor, determines whether the current state is static or moving through the acceleration changes of the three axes, and determines the light signal of the optical sensor only in the static state.

[0045] A human skin wearing recognition method based on multiple sensors is applied to a human skin wearing recognition system based on multiple sensors, comprising the following steps:

[0046] The central microcontroller receives the acceleration signal from the acceleration sensor and determines whether the wearable device is currently in a stationary state or in motion through the acceleration changes of the three axes;

[0047] When the device is stationary, the optical sensor and the capacitive sensor are combined to determine the wearing status.

[0048] When in motion, use the capacitive sensor to determine the wearing status;

[0049] Output wearing status.

[0050] In this embodiment, the capacitive sensor and the optical sensor are both in a normally closed state;

[0051] After the acceleration sensor detects that the wearable device changes from a static state to a motion state, the capacitive sensor is turned on, which is beneficial for saving power consumption in a non-motion state;

[0052] After the acceleration sensor detects that the wearable device is converted from a moving state to a stationary state, the capacitive sensor detects the skin capacitance induction, and the optical sensor is turned on when the condition of sensing the proximity of the conductor is met, thereby greatly reducing the frequency of the optical sensor and its related communications and algorithm calls, thereby saving the optical sensor transmitter module driving power consumption, the corresponding communication power consumption and the algorithm call power consumption, because the static state is recognized faster and more accurately in non-skin scenarios by capacitance, but the capacitance can only recognize conductors, and cannot accurately distinguish between skin and other conductors. After the conductor is recognized, optical re-judgment is required. In dynamic scenarios, the optical sensor only detects the proximity of objects, and does not distinguish between skin or objects. The capacitive sensor can be used to distinguish between skin or objects.

[0053] When the wearing state is output, if it is in the wearing state and the state is static at this time, the capacitive sensor and the optical sensor are turned off to save power consumption.

[0054] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A human skin wearing recognition system based on multiple sensors, characterized in that: It includes optical sensors, acceleration sensors, capacitive sensors and a central micro control unit; Optical sensors are used to detect skin reflection signals; Capacitive sensors are used to detect skin capacitance sensing; Accelerometers are used to detect stillness and motion; The central micro control unit receives the three signals and determines whether the device is currently worn on human skin or a non-skin object.

2. A human skin wearing recognition system based on multiple sensors according to claim 1, characterized in that: The optical sensor includes a transmitting module, a receiving module and a first signal processing module. The transmitting module drives the LED to emit light, which is irradiated onto the skin. The reflected light is sensed as photocurrent by the receiving module, which is converted into a digital signal by the first signal processing module and then sent to the central micro control unit.

3. A human skin wearing recognition system based on multiple sensors according to claim 2, characterized in that: The LED driven by the transmitting module adopts green light and infrared light.

4. A human skin wearing recognition system based on multiple sensors according to claim 3, characterized in that: The capacitive sensor includes a sensing electrode and a second signal processing module. The sensing electrode senses the conductor and converts the signal into a digital signal through the second signal processing module and then sends the digital signal to the central micro control unit.

5. A human skin wearing recognition system based on multiple sensors according to claim 4, characterized in that: The sensing electrodes are arranged around the transmitting module of the optical sensor and are close to the transmitting module.

6. The human skin wearing recognition system based on multiple sensors according to claim 1, characterized in that: The area of ​​the sensing electrode is greater than 20 square millimeters.

7. The human skin wearing recognition system based on multiple sensors according to claim 1 is characterized in that: The central micro control unit receives the signal from the optical sensor, calculates the spectrum energy of the human pulse signal by spectrum integration, and calculates the signal-to-noise ratio with other noise signals, thereby determining whether it is a human skin reflection signal.

8. The human skin wearing recognition system based on multiple sensors according to claim 1, characterized in that: The central micro control unit receives the acceleration signal from the acceleration sensor, determines whether the current state is static or moving through the acceleration changes of the three axes, and determines the light signal of the optical sensor only in the static state.

9. A human skin wearing recognition method based on multiple sensors, applied to a human skin wearing recognition system based on multiple sensors as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: The central microcontroller receives the acceleration signal from the acceleration sensor and determines whether the wearable device is currently in a stationary state or in motion through the acceleration changes of the three axes; When the device is stationary, the optical sensor and the capacitive sensor are combined to determine the wearing status. When in motion, use the capacitive sensor to determine the wearing status; Output wearing status.

10. The method for identifying human skin wearing based on multiple sensors according to claim 9, characterized in that: The capacitive sensor and the optical sensor are both in a normally closed state; After the acceleration sensor detects that the wearable device changes from a static state to a motion state, the capacitive sensor is turned on, which is beneficial for saving power consumption in a non-motion state; After the acceleration sensor detects that the wearable device is converted from a moving state to a stationary state, the capacitive sensor detects the skin capacitance induction, and if the condition that the conductor is approaching is met, the optical sensor is turned on, thereby saving the driving power consumption of the optical sensor transmitting module; When the wearing state is output, if it is in the wearing state and the state is static at this time, the capacitive sensor and the optical sensor are turned off to save power consumption.

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