Anti-drowning intelligent swimming goggles and anti-drowning monitoring method thereof

Abstract

The invention discloses a pair of anti-drowning intelligent swimming goggles and an anti-drowning monitoring method thereof, and relates to the field of drowning monitoring, and the method comprises the steps: setting the structure of the anti-drowning intelligent swimming goggles, initializing a sampling channel, setting terminal pairing binding and synchronization with monitoring parameters, and initializing an anti-drowning monitoring state machine and a continuous underwater time counter. Through fusion of double-water immersion electrode impedance detection and a Bluetooth low-power-consumption received signal strength indication value, and in combination with a state machine management structure and a continuous in-water time counter, identification of a non-water-entry state, a water entry state, a water outlet candidate state and an effective water outlet state is realized. Based on the effective ventilation judgment time threshold parameter, the drowning risk judgment in-water time threshold parameter and the intermediate alarm time point, the multi-stage alarm module is driven to output graded optical alarm, vibration alarm and information alarm, and a guardian adjusts the threshold parameters through a guardian mobile phone application program terminal. And the false alarm rate control and the drowning risk identification sensitivity are considered in different age groups and swimming scenes.

Description

Technical Field

[0001] This invention relates to the field of drowning monitoring, and in particular to a smart swimming goggle for preventing drowning and a method for monitoring drowning prevention. Background Technology

[0002] Despite the increasing popularity of swimming, water recreation, and open water activities, drowning accidents involving children and teenagers remain frequent. Current drowning prevention measures largely rely on on-site lifeguard patrols, underwater camera monitoring, and simple wearable water immersion detection devices. Some wearable devices identify water immersion status solely through a single conductive electrode or a change in the strength of a single wireless signal, and are usually accompanied by fixed timeout thresholds for alarms. This makes it difficult to continuously and precisely monitor and alert about drowning risks without disrupting the normal swimming rhythm.

[0003] Existing drowning prevention monitoring devices based on a single water immersion signal or a single received signal strength indicator value have difficulty distinguishing between normal breathing behavior and silent sinking processes when the wearer frequently enters and exits the water and breathes while swimming on their back. This can easily lead to false alarms or missed alarms. The continuous time spent in the water cannot be stably characterized. Furthermore, many devices only set a fixed alarm threshold for the time spent in the water, lacking graded warning and parameter adaptive adjustment mechanisms for different age groups, swimming abilities, and water environments. This results in the alarm rhythm not being synchronized with the actual evolution of drowning risk. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a smart anti-drowning swimming goggle and its anti-drowning monitoring method. This method integrates dual water-immersion electrodes, an impedance detection circuit, and a short-range wireless communication module into the nose pad. A state machine management structure and a continuous underwater time counter are constructed using a main control chip. The system combines impedance time series and received signal strength indication time series to identify water entry status, identify candidate water exit events, and determine effective breathing. Furthermore, it works in conjunction with underwater time threshold parameters for drowning risk assessment and intermediate alarm time points to drive multi-level alarm modules, enabling early and tiered alerts for high-risk drowning events while ensuring a normal swimming experience.

[0005] Therefore, this application provides a smart swimming goggle for preventing drowning and a method for monitoring drowning prevention therebetween, comprising the following steps: Step S100: Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, set the terminal pairing and binding and synchronization with the monitoring parameters, and initialize the anti-drowning monitoring state machine and the continuous underwater time counter.

[0006] Step S200: Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value. Based on the received signal strength indication value, identify the water entry status and update the state machine.

[0007] Step S300: Set the detection window structure and key parameter extraction, set the water effluent candidate event judgment logic, and set the effective air exchange judgment and state machine update.

[0008] Step S400: Set up continuous immersion status confirmation and counter accumulation, execute continuous underwater time accumulation pause and count value reset, set up communication anomaly tolerance mechanism and continuous underwater time accumulation error suppression strategy, and configure underwater time threshold parameters for drowning risk assessment and highest level alarm triggering logic.

[0009] Step S500: Configure multi-level alarm triggering conditions and early warning mode output strategies, set the triggering of the highest level alarm mode and multi-terminal linkage response mechanism, and configure key monitoring parameters to adapt.

[0010] In some specific embodiments, step S100 specifically includes: Step S100.1: Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, and set the terminal pairing and binding and synchronization with the monitoring parameters.

[0011] Step S100.2: Initialize the drowning prevention monitoring state machine and the continuous underwater time counter.

[0012] After the main control chip completes the writing of key monitoring parameters, it builds a state machine management structure inside the main control chip to manage the drowning prevention monitoring process. The state machine management structure is used to distinguish between non-water entry state, water entry state, water exit candidate state, and other drowning prevention monitoring related states. After the state machine management structure is built, the main control chip sets the initial state of the state machine management structure to the non-water entry state, so that the drowning prevention smart swimming goggles are in the non-water entry monitoring state by default during the initial stage of wearing.

[0013] The anti-drowning smart swimming goggles are equipped with a multi-level alarm module, which includes a waterproof indicator light alarm unit, a vibration alarm unit for the guardian's wristband terminal, and an information alarm unit for the guardian's mobile application terminal. During subsequent anti-drowning monitoring, the multi-level alarm module executes graded alarms based on the count value of the continuous underwater time counter and the underwater time threshold parameter for determining the drowning risk. After the main control chip completes the initialization of the state machine management structure, the preset alarm time points of the multi-level alarm module, and the initialization of the continuous underwater time counter, it sets the current working state of the anti-drowning smart swimming goggles to the state where impedance acquisition, Bluetooth low power signal strength acquisition, and anti-drowning monitoring logic can be executed.

[0014] In some specific embodiments, step S200 specifically includes: Step S200.1: Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value.

[0015] Step S200.2: Identify water entry status and update state machine based on received signal strength indication value.

[0016] In some specific embodiments, step S300 specifically includes: Step S300.1: Set the detection window structure and extract key parameters, and set the logic for judging water effluent candidate events.

[0017] Step S300.2: Set the effective air exchange judgment and state machine update, and identify invalid water discharge events and revert the water state.

[0018] In some specific embodiments, step S400 specifically includes: Step S400.1: Set the continuous immersion status confirmation and counter accumulation, and execute the continuous water time accumulation pause and count value reset.

[0019] Step S400.2: Set up a communication anomaly tolerance mechanism and a continuous underwater time accumulation error suppression strategy, and configure the underwater time threshold parameter for drowning risk assessment and the highest level alarm triggering logic.

[0020] The main control chip introduces a communication anomaly tolerance mechanism and a continuous water time accumulation error suppression strategy during the continuous water time accumulation process, and analyzes and processes short-term anomalies in the Bluetooth Low Energy communication link.

[0021] During the sampling period when the Bluetooth Low Energy communication link status indicator indicates a short-term connection interruption, the main control chip continuously analyzes the impedance time series and the recovery trend of the received signal strength indicator value.

[0022] When the main control chip detects that the impedance change rate parameter continues to show a trend of changing towards dryness, or the received signal strength indicator value recovers to above -85dBm in a short time but does not meet the conditions for judging the water discharge candidate event, the main control chip keeps the current state field of the state machine management structure unchanged, continues to maintain the judgment of the water inlet state or the effective water discharge state, and keeps the continuous water time counter maintaining the original accumulation strategy.

[0023] The communication anomaly tolerance mechanism and the continuous underwater time accumulation error suppression strategy smooth out transient data anomalies caused by Bluetooth Low Energy communication link disturbances.

[0024] The main control chip reads the continuous water time counter value in real time. When the continuous water time counter value is greater than or equal to the risk judgment threshold, the chip will detect the time counter value. At that time, the main control chip determined that the wearer was in a high-risk drowning state.

[0025] In some specific embodiments, step S500 specifically includes: Step S500.1: Configure multi-level alarm triggering conditions and early warning mode output strategies, and set the triggering of the highest level alarm mode and multi-terminal linkage response mechanism.

[0026] Step S500.2: Configure key monitoring parameters to adapt.

[0027] When any level of alarm event is triggered, the main control chip generates a multi-level alarm event record through the event recording storage area inside the main control chip. The multi-level alarm event record includes the alarm trigger timestamp, the peak value of the continuous underwater time counter at the alarm trigger time, the swimming scene identification information at the time of wearing, the alarm level status identifier, and the Bluetooth Low Energy communication link status snapshot.

[0028] After generating multi-level alarm event records, the main control chip uses a short-range wireless communication module mounted on a flexible circuit board structure to send the multi-level alarm event records to the guardian's mobile application terminal according to a predetermined data format. The guardian's mobile application terminal stores and lists the multi-level alarm event records in a structured manner in its local cache, allowing the guardian to review each warning event and drowning high-risk alarm event, and analyze and evaluate the existing parameter configuration based on the peak value of the continuous underwater time counter and swimming scene identification information.

[0029] The wireless communication module can employ Bluetooth Low Energy (BLE), NearLink, Zigbee, or other short-range wireless communication technologies, as long as it can provide periodic Received Signal Strength Indication (RSSI) values.

[0030] The guardian can adaptively adjust the effective breathing time threshold parameter T1, the drowning risk assessment underwater time threshold parameter T2, and the graded alarm triggering time point parameter based on the wearer's age group, swimming skill level, and the water depth and rescue response conditions of the swimming venue.

[0031] In summary, the drowning prevention smart swimming goggles and their drowning prevention monitoring method provided in this application integrate dual water immersion electrode impedance detection with Bluetooth Low Energy received signal strength indication value, combined with a state machine management structure and a continuous underwater time counter, to identify non-water entry state, water entry state, candidate exit state, and effective exit state. Based on the effective breathing judgment time threshold parameter, the drowning risk judgment underwater time threshold parameter, and intermediate alarm time points, the multi-level alarm module outputs hierarchical optical alarm, vibration alarm, and information alarm. The guardian can adjust the threshold parameters through the guardian's mobile application terminal, balancing false alarm rate control and drowning risk identification sensitivity in different age groups and swimming scenarios. Attached Figure Description

[0032] Figure 1This is an overall flowchart of a drowning prevention smart swimming goggle and its drowning prevention monitoring method provided in the embodiments of this application. Detailed Implementation

[0033] Please refer to Figure 1 The present invention illustrates a flow chart of an embodiment of a drowning prevention smart swimming goggle and a drowning prevention monitoring method according to the present disclosure.

[0034] like Figure 1 As shown, a smart swimming goggle for preventing drowning and its drowning monitoring method include the following steps: Step S100: Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, set the terminal pairing and binding and synchronization with the monitoring parameters, and initialize the anti-drowning monitoring state machine and the continuous underwater time counter.

[0035] Step S200: Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value. Based on the received signal strength indication value, identify the water entry status and update the state machine.

[0036] Step S300: Set the detection window structure and key parameter extraction, set the water effluent candidate event judgment logic, and set the effective air exchange judgment and state machine update.

[0037] Step S400: Set up continuous immersion status confirmation and counter accumulation, execute continuous underwater time accumulation pause and count value reset, set up communication anomaly tolerance mechanism and continuous underwater time accumulation error suppression strategy, and configure underwater time threshold parameters for drowning risk assessment and highest level alarm triggering logic.

[0038] Step S500: Configure multi-level alarm triggering conditions and early warning mode output strategies, set the triggering of the highest level alarm mode and multi-terminal linkage response mechanism, and configure key monitoring parameters to adapt.

[0039] In some specific embodiments, step S100 specifically includes: Step S100.1: Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, and set the terminal pairing and binding and synchronization with the monitoring parameters.

[0040] The anti-drowning smart swimming goggles include a frame body, left and right mirror cavities located on the left and right sides of the frame body, and a nose pad connecting the left and right mirror cavities. A flexible circuit board structure is fixedly installed inside the nose pad. A main control chip, dual water immersion electrodes, a short-range wireless communication module, and an impedance detection circuit electrically connected to the main control chip are sequentially soldered onto the flexible circuit board structure. The dual water immersion electrodes are arranged on the side of the nose pad closest to the wearer's face to form a conductive path with the water and the wearer's facial skin.

[0041] After the anti-drowning smart swimming goggles are connected to a power source, the main control chip, based on the power supply path provided by the flexible circuit board structure, is in a powered-on state. In the powered-on state, the main control chip first activates the impedance detection circuit that is electrically connected to the dual water immersion electrodes inside the main control chip. The impedance detection circuit is used to periodically collect the impedance of the dual water immersion electrodes. At the same time, the main control chip activates the short-range wireless communication module installed on the flexible circuit board structure. The short-range wireless communication module and the main control chip use a serial communication bus for data interaction.

[0042] After the main control chip completes the startup of the impedance detection circuit and the short-range wireless communication module, a dual water immersion electrode sampling channel is configured between the dual water immersion electrodes and the main control chip, and a Bluetooth low power signal strength sampling channel is configured between the short-range wireless communication module and the main control chip.

[0043] The main control chip constructs a unified sampling time base based on a millisecond-level time base. Under this unified sampling time base, the main control chip sets the impedance sampling period to 20ms and the Bluetooth Low Energy signal strength sampling period to 50ms. After completing the initialization of the dual water immersion electrode sampling channel and the Bluetooth Low Energy signal strength sampling channel, the main control chip sets the current working state of the anti-drowning smart swimming goggles to the sampling preparation state for performing anti-drowning monitoring tasks.

[0044] After the anti-drowning smart swimming goggles complete the sampling preparation state setting, the main control chip uses a short-range wireless communication module installed on a flexible circuit board structure to search for external terminals. The external terminals include a guardian wristband terminal and a guardian mobile application terminal. The guardian wristband terminal is a wearable terminal worn on the guardian's wrist. The guardian wristband terminal integrates a short-range wireless communication module and a vibration reminder unit.

[0045] The guardian's mobile application terminal is a smartphone terminal with the drowning prevention monitoring application installed. The drowning prevention monitoring application is used to configure parameters and display alarm information for the drowning prevention smart swimming goggles.

[0046] After detecting the guardian's wristband terminal and the guardian's mobile application terminal, the main control chip establishes Bluetooth Low Energy connections with both terminals sequentially and completes pairing. After successful pairing, the main control chip first accesses its internal local parameter storage area and reads key monitoring parameters from it. If the local parameter storage area does not store key monitoring parameters, the main control chip receives the key monitoring parameters from the guardian's mobile application terminal via a short-range wireless communication module and writes the received key monitoring parameters into the local parameter storage area.

[0047] Key monitoring parameters include: effective ventilation time threshold, drowning risk assessment time in water threshold, impedance change rate threshold, and Bluetooth Low Energy signal strength step enhancement threshold.

[0048] The effective ventilation judgment time threshold parameter is set to 0.8 seconds to distinguish between effective water expulsion behavior and brief ineffective water expulsion behavior. The drowning risk judgment underwater time threshold parameter is set to 45 seconds to serve as a drowning risk trigger judgment condition. The impedance change rate judgment threshold parameter is set to 15 kΩ / s to identify the rapid change process of the dual water immersion electrodes from the water immersion state to the non-water immersion state. The Bluetooth Low Energy signal strength step enhancement threshold parameter is set to 10 dB to identify the rapid enhancement process of Bluetooth Low Energy signal strength when the anti-drowning smart swimming goggles cross the water interface.

[0049] After synchronizing the effective air exchange determination time threshold parameters, the drowning risk determination underwater time threshold parameters, the impedance change rate determination threshold parameters, and the Bluetooth Low Energy signal strength step enhancement threshold parameters, the main control chip writes these parameters into the operating parameter storage area inside the main control chip, enabling the anti-drowning smart swimming goggles to have the monitoring parameter basis for performing anti-drowning monitoring tasks.

[0050] Step S100.2: Initialize the drowning prevention monitoring state machine and the continuous underwater time counter.

[0051] After the main control chip completes the writing of key monitoring parameters, it builds a state machine management structure inside the main control chip to manage the drowning prevention monitoring process. The state machine management structure is used to distinguish between non-water entry state, water entry state, water exit candidate state, and other drowning prevention monitoring related states. After the state machine management structure is built, the main control chip sets the initial state of the state machine management structure to the non-water entry state, so that the drowning prevention smart swimming goggles are in the non-water entry monitoring state by default during the initial stage of wearing.

[0052] The main control chip also builds a continuous underwater time counter inside the main control chip. The continuous underwater time counter is used to record the continuous underwater time of the wearer in a fully submerged state. When the continuous underwater time counter is initialized, the count value of the continuous underwater time counter is set to 0 seconds. The continuous underwater time counter accumulates time based on the unified time base of the main control chip.

[0053] The main control chip presets two intermediate alarm time points of 30 seconds and 40 seconds in the continuous underwater time counter. The 30-second intermediate alarm time point is used to provide an early warning before the wearer approaches the underwater time threshold parameter for drowning risk assessment, and the 40-second intermediate alarm time point is used to provide a stronger warning when the wearer gets closer to the underwater time threshold parameter for drowning risk assessment.

[0054] The anti-drowning smart swimming goggles are equipped with a multi-level alarm module, which includes a waterproof indicator light alarm unit, a vibration alarm unit for the guardian's wristband terminal, and an information alarm unit for the guardian's mobile application terminal. During subsequent anti-drowning monitoring, the multi-level alarm module executes graded alarms based on the count value of the continuous underwater time counter and the underwater time threshold parameter for determining the drowning risk. After the main control chip completes the initialization of the state machine management structure, the preset alarm time points of the multi-level alarm module, and the initialization of the continuous underwater time counter, it sets the current working state of the anti-drowning smart swimming goggles to the state where impedance acquisition, Bluetooth low power signal strength acquisition, and anti-drowning monitoring logic can be executed.

[0055] In some specific embodiments, step S200 specifically includes: Step S200.1: Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value.

[0056] After the main control chip sets the current working state of the anti-drowning smart swimming goggles to the state of being able to perform impedance acquisition, Bluetooth low power signal strength acquisition, and anti-drowning monitoring logic, the main control chip starts to perform the real-time acquisition process of impedance signals based on the dual water immersion electrode sampling channel. The dual water immersion electrodes consist of a first water immersion electrode and a second water immersion electrode. Both the first and second water immersion electrodes are fixedly installed on the lower inner side of the flexible circuit board structure inside the nose pad and are arranged towards the wearer's face and the water. The first and second water immersion electrodes are electrically connected to the main control chip through wires, forming a closed impedance sampling loop between the first and second water immersion electrodes.

[0057] The main control chip periodically acquires the voltage signal between the first and second water immersion electrodes according to the impedance sampling period, which is 20 milliseconds.

[0058] The main control chip uses an impedance detection circuit to amplify the acquired raw analog voltage signal and uses an analog-to-digital converter to convert the raw analog voltage signal into a digital voltage sampling value.

[0059] The main control chip applies a constant excitation current to the impedance detection circuit. The value of the constant excitation current is set and written into the local parameter storage area of ​​the main control chip during the design stage of the anti-drowning smart swimming goggles.

[0060] The main control chip calculates the corresponding impedance value based on the digital voltage sampling value and the constant excitation current value, forming an impedance time series. The impedance time series is represented by the following expression: In the formula, For time The impedance value between the first and second water-immersion electrodes at any given time. For time The voltage sampling value between the first and second water immersion electrodes at a given time. The value of the constant excitation current applied between the first and second water-immersed electrodes.

[0061] Based on the impedance time series, the main control chip constructs a sliding time window structure internally, with the time length of the sliding time window structure set to 100 milliseconds.

[0062] Within each sliding time window, the main control chip calculates the impedance change rate parameter based on the impedance value at the end of the current time window and the impedance value at the end of the previous time window. The impedance change rate parameter is expressed by the following expression: In the above formula, For time The impedance change rate parameter at time . For time The impedance value between the first and second water-immersion electrodes at any given time. For time The impedance value between the first and second water-immersion electrodes at any given time. The time length of the sliding time window structure. The value is 0.1 seconds.

[0063] The main control chip uses the impedance change rate parameter as a criterion to reflect the transition process of the first and second water-immersed electrodes from a state of complete immersion in water to a state of partial exposure to air. The impedance change rate parameter is used as an algorithm input in the subsequent water outage event identification and effective ventilation determination process.

[0064] While the main control chip performs impedance signal acquisition and impedance change rate calculation, it also uses the Bluetooth Low Energy signal strength sampling channel to collect the Bluetooth Low Energy communication link status between the anti-drowning smart swimming goggles and the guardian's wristband terminal in real time.

[0065] During the initialization phase of the anti-drowning smart swimming goggles, the guardian's wristband terminal has completed pairing and binding with the anti-drowning smart swimming goggles and established a Bluetooth Low Energy connection. The Bluetooth Low Energy communication link maintains data interaction after the connection is established.

[0066] The main control chip periodically collects the received signal strength indication value of the current Bluetooth Low Energy communication link according to the Bluetooth Low Energy signal strength sampling period, which is 50 milliseconds.

[0067] The main control chip acquires the received signal strength indication value in the short-range wireless communication module and records the received signal strength indication value as... The strength value is maintained by the main control chip in its internal storage space. The time series of received signal strength indicators, composed of intensity values, is used to characterize the wireless channel attenuation characteristics between the guardian's wristband terminal and the anti-drowning smart swimming goggles.

[0068] When the wearer is completely immersed in water, the water medium significantly attenuates and reflects the 2.4GHz Bluetooth Low Energy wireless signal. The main control chip detects this within multiple consecutive sampling periods. The intensity value remains stable below -90 dBm. When the anti-drowning smart swimming goggles gradually approach the water surface with the wearer's head and break through the water surface, the main control chip detects this within a short time. The strength value increases rapidly. The increase in intensity value is greater than 10 dB, typically in the case of The strength value can be increased to approximately -75 dBm.

[0069] The main control chip uses a moving average processing method to process the time series of received signal strength indication values. It calculates the average received signal strength indication value by taking multiple consecutive sampling periods as a group. The moving average processing is used to suppress the jitter of received signal strength caused by transient interference.

[0070] After completing the sliding average processing, the main control chip quantifies the current Bluetooth Low Energy (BLE) communication link status by considering whether a connection interruption event has occurred, thus forming a Bluetooth BLE communication link status identifier.

[0071] Step S200.2: Identify water entry status and update state machine based on received signal strength indication value.

[0072] After obtaining the impedance time series, impedance change rate parameter, received signal strength indication value time series, and Bluetooth Low Energy communication link status identifier, the main control chip makes a comprehensive judgment on whether the wearer is in water.

[0073] During the device design phase, the anti-drowning smart swimming goggles pre-write water ingress impedance threshold parameters and underwater signal strength indication threshold parameters in the local parameter storage area of ​​the main control chip. The value of the water ingress impedance threshold parameter is 5 kiloohms, and the value of the underwater signal strength indication threshold parameter is -85 dBm.

[0074] Within each impedance sampling cycle, the main control chip executes water entry status identification logic based on three conditions: First, the current impedance value is less than the 5 kΩ water entry impedance threshold represented by the water entry impedance threshold parameter; second, the current received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter; and third, the current Bluetooth Low Energy communication link status indicator indicates that the Bluetooth Low Energy communication link is in a normal connection state, and the received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter for multiple consecutive sampling cycles.

[0075] When the current impedance value is less than the 5 kΩ water impedance threshold represented by the water ingress impedance threshold parameter, the current received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter, and the current Bluetooth Low Energy communication link status indicator indicates that the Bluetooth Low Energy communication link is in a normal connection state, and the received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter in multiple consecutive sampling periods, the main control chip updates the current state field in the state machine management structure from the non-water ingress state to the water ingress state, and sets the counting activation flag bit in the continuous underwater time counter to the active state, so that the continuous underwater time counter starts to accumulate the continuous underwater time of the wearer in the fully submerged state at a preset time step.

[0076] The continuous underwater time accumulated by the continuous underwater time counter is used as the core basis for subsequent drowning risk assessment and multi-level alarm threshold comparison.

[0077] When the state machine management structure changes from the non-water entry state to the water entry state, the main control chip writes a state change record in the event record storage area inside the main control chip. The state change record includes a state change timestamp, a state identifier before the state change, and a state identifier after the state change.

[0078] After completing the status change record, the main control chip sends the water entry status change identifier information to the guardian's mobile application terminal through the short-range wireless communication module. This enables the guardian's mobile application terminal to visualize and track the wearer's water entry start time and water entry process during subsequent effective air exchange determination, drowning risk accumulation determination, and multi-level alarm linkage.

[0079] In some specific embodiments, step S300 specifically includes: Step S300.1: Set the detection window structure and extract key parameters, and set the logic for judging water effluent candidate events.

[0080] When the main control chip is in the "water entry" state in the state machine management structure, a detection window structure is configured in the internal running storage area of ​​the main control chip. This detection window structure is used to extract and calculate the impedance change rate parameter and the received signal strength indication value within a fixed time period. The time period of the detection window structure is denoted as... Length of time The value is set to That is, 300 milliseconds.

[0081] Within the time interval corresponding to each detection window structure, the main control chip extracts the impedance change rate parameter at the end of the detection window based on the impedance time series and the impedance change rate calculation expression. The impedance change rate calculation expression is as follows: In the formula: For time The impedance change rate parameter at time . For time The impedance value between the first and second water-immersion electrodes at any given time. For time The impedance value between the first and second water-immersion electrodes at any given time. The time interval used for calculating the rate of change of impedance The value is .

[0082] Within the detection window structure, the main control chip simultaneously performs endpoint differential calculations on the time series of the received signal strength indication value, extracting the change in received signal strength within the corresponding time interval of the detection window structure. The expression for calculating the change in received signal strength is: In the formula: To detect the change in received signal strength within the time interval corresponding to the window structure, To detect the received signal strength indication value at the end of the detection window, This is the received signal strength indication value at the start of the detection window.

[0083] At the end of the time interval corresponding to each detection window structure, the main control chip caches the impedance change rate parameter and the change in received signal strength at the end of the time interval as input for water discharge event determination.

[0084] After extracting the impedance change rate parameter and the received signal strength change, the main control chip retrieves the impedance change rate judgment threshold parameter and the Bluetooth Low Energy signal strength step enhancement threshold parameter from the main control chip's operating parameter storage area. The value of the impedance change rate judgment threshold parameter is set as follows: The value of the Bluetooth Low Energy signal strength step enhancement threshold parameter is set as follows: The impedance change rate threshold parameter is used to identify the rapid thinning of the water film on the surfaces of the first and second water-immersed electrodes. The Bluetooth Low Energy signal strength step enhancement threshold parameter is used to identify the rapid enhancement of the received signal strength after the anti-drowning smart swimming goggles cross the water interface.

[0085] At the end of the time interval corresponding to each detection window structure, the main control chip determines the candidate water effluent event according to two conditions: the impedance change rate parameter at the end of the current detection window structure satisfies the following relationship: The change in received signal strength corresponding to the current detection window structure satisfies the following relationship: When the conditions for determining the rate of change of impedance and the condition for determining the change in received signal strength are met simultaneously.

[0086] The main control chip updates the current state field in the state machine management structure from the water inlet state to the water outlet candidate state, and builds a water outlet duration timer inside the main control chip. The water outlet duration timer is used to record the continuous time length from the start of the water outlet candidate state to the end of the water outlet state. When the water outlet duration timer is built, the count value is initialized to 0 seconds.

[0087] Step S300.2: Set the effective air exchange judgment and state machine update, and identify invalid water discharge events and revert the water state.

[0088] When the state machine management structure is in the water outlet candidate state, the main control chip initiates the effective air exchange determination logic. The main control chip pre-writes the effective air exchange determination time threshold parameter in the local parameter storage area. The effective air exchange determination time threshold parameter is denoted as... The effective ventilation determination time threshold parameter is set as follows: When the water discharge candidate state is in progress, the main control chip continuously monitors the water discharge duration timer count, the Bluetooth Low Energy communication link status indicator, and the received signal strength indicator.

[0089] When all three conditions are met, the main control chip determines the current water expulsion behavior as a valid ventilation behavior: the Bluetooth Low Energy communication link status indicator shows that the Bluetooth Low Energy communication link between the anti-drowning smart swimming goggles and the guardian's wristband terminal is in a stable connection state; the received signal strength indicator value remains continuously within the water expulsion signal strength range during the water expulsion candidate state, with a typical value range of −75dBm to −65dBm; and the count value of the water expulsion duration timer is greater than or equal to the valid ventilation determination time threshold parameter. That is, satisfying the relation: , The current water outflow duration recorded by the water outflow duration timer.

[0090] When the Bluetooth Low Energy communication link connection is stable, the received signal strength range, and the water discharge duration are simultaneously met, the main control chip updates the current state field in the state machine management structure to a valid water discharge state and resets the count value in the continuous water time counter to 0 seconds, so that the continuous water time counter can start recording the continuous water time corresponding to the next water entry process.

[0091] If any situation occurs during the operation of the water discharge duration timer while the main control chip is in the water discharge candidate state of the state machine management structure, the main control chip will determine the current water discharge behavior as invalid. The situations include: the water discharge duration recorded by the water discharge duration timer is less than the effective ventilation determination time threshold parameter. ,Right now The received signal strength indicator value falls back into the underwater received signal strength range defined by the underwater received signal strength indicator threshold parameter within the continuous sampling period. The typical value of the underwater received signal strength indicator threshold parameter is -85 dBm and below. The impedance value between the first and second underwater immersion electrodes was detected to have dropped rapidly again in a short period of time through impedance time series and impedance change rate parameters. This indicates that the first and second underwater immersion electrodes are completely covered by water again. Invalid water surfacing behavior usually corresponds to the wearer briefly raising their head, short-term water surfacing of local body parts, or struggling movements, which cannot provide the wearer with sufficient breathing and ventilation. When the invalid water exit behavior judgment condition is triggered, the main control chip restores the current state field in the state machine management structure from the water exit candidate state to the water entry state, and keeps the count value of the continuous water time counter unchanged, so that the continuous water time counter continues to accumulate the wearer's continuous water time in the fully submerged state, thereby improving the sensitivity of the anti-drowning smart swimming goggles to identify silent sinking scenarios and hidden drowning processes.

[0092] In some specific embodiments, step S400 specifically includes: Step S400.1: Set the continuous immersion status confirmation and counter accumulation, and execute the continuous water time accumulation pause and count value reset.

[0093] When the current state field of the state machine management structure is in the water immersion state, the main control chip uses the short-range wireless communication module to collect the Bluetooth Low Energy communication link status identifier and confirms whether the wearer is continuously in a fully submerged state based on the time series of the received signal strength indicator value. The main control chip calls the underwater received signal strength indicator value threshold parameter in the local parameter storage area. The value of the underwater received signal strength indicator value threshold parameter is set to −85dBm. The underwater received signal strength indicator value threshold parameter is used as the basis for confirming the fully submerged state.

[0094] When the Bluetooth Low Energy (BLE) link status indicator indicates that the BLE link is in a connection interruption state, or when the received signal strength indicator value is lower than the underwater received signal strength indicator value threshold parameter of −85dBm for multiple consecutive sampling periods, the main control chip determines that the wearer is currently in a state of continuous immersion in water.

[0095] The main control chip is based on a unified sampling time reference and accumulates the count value of the continuous underwater time counter with a sampling period of 100 milliseconds. In each 100-millisecond sampling period, the count value of the continuous underwater time counter is increased by 0.1 seconds, so that the continuous underwater time counter forms a high-precision accumulation process of the wearer's continuous underwater time.

[0096] When the current state field of the main control chip in the state machine management structure is in the water discharge candidate start state or the effective water discharge state, the counting value accumulation operation of the continuous water time counter is paused. The water discharge candidate start state and the effective water discharge state are generated by the main control chip in the water discharge event detection and effective air exchange determination module after switching the state machine by combining the impedance change rate parameter and the change of the received signal strength indication value.

[0097] The main control chip calls the effective ventilation judgment time threshold parameter in the local parameter storage area. The value of the effective ventilation judgment time threshold parameter is set to 0.8 seconds. The main control chip judges the effective ventilation based on the water outlet duration recorded by the water outlet duration timer. When the water outlet duration recorded by the water outlet duration timer is greater than or equal to the effective ventilation judgment time threshold parameter, the main control chip sets the current state field of the state machine management structure to the effective water outlet state and resets the count value of the continuous water time counter to 0 seconds.

[0098] Step S400.2: Set up a communication anomaly tolerance mechanism and a continuous underwater time accumulation error suppression strategy, and configure the underwater time threshold parameter for drowning risk assessment and the highest level alarm triggering logic.

[0099] The main control chip introduces a communication anomaly tolerance mechanism and a continuous water time accumulation error suppression strategy during the continuous water time accumulation process, and analyzes and processes short-term anomalies in the Bluetooth Low Energy communication link.

[0100] During the sampling period when the Bluetooth Low Energy communication link status indicator indicates a short-term connection interruption, the main control chip continuously analyzes the impedance time series and the recovery trend of the received signal strength indicator value.

[0101] When the main control chip detects that the impedance change rate parameter continues to show a trend of changing towards dryness, or the received signal strength indicator value recovers to above -85dBm in a short time but does not meet the conditions for judging the water discharge candidate event, the main control chip keeps the current state field of the state machine management structure unchanged, continues to maintain the judgment of the water inlet state or the effective water discharge state, and keeps the continuous water time counter maintaining the original accumulation strategy.

[0102] The communication anomaly tolerance mechanism and the continuous underwater time accumulation error suppression strategy smooth out transient data anomalies caused by Bluetooth Low Energy communication link disturbances.

[0103] The main control chip presets a drowning risk assessment underwater time threshold parameter in the operating parameter storage area. This underwater time threshold parameter is recorded as the risk assessment threshold. Risk assessment threshold The default value is: Risk assessment threshold The default value is set based on the golden intervention window for drowning rescue recommended by the World Health Organization. The guardian's mobile application terminal provides the risk assessment threshold in the parameter configuration interface. The personalized adjustment portal allows guardians to adjust risk assessment thresholds based on the wearer's swimming ability level, the water depth of the location, and rescue response conditions. Adjustments will be made.

[0104] The main control chip reads the continuous water time counter value in real time. When the continuous water time counter value is greater than or equal to the risk judgment threshold, the chip will detect the time counter value. At that time, the main control chip determined that the wearer was in a high-risk drowning state.

[0105] During the device design phase, the main control chip is configured with an execution command interface. This interface is used to send alarm control information to the waterproof indicator light alarm unit, the guardian's wristband vibration alarm unit, and the guardian's mobile application terminal information alarm unit according to different alarm levels. When the main control chip determines that the wearer is in a high-risk drowning state, it uses the execution command interface to send the highest-level optical alarm control information to the waterproof indicator light alarm unit, causing the waterproof indicator light alarm unit to flash at high brightness and high frequency; it sends the highest-level vibration alarm control information to the guardian's wristband vibration alarm unit, causing the guardian's wristband vibration alarm unit to vibrate at high frequency multiple times; and it sends the highest-level information alarm control information to the guardian's mobile application terminal information alarm unit, causing the guardian's mobile application terminal information alarm unit to display a red high-priority alarm notification and activate an audio prompt on the guardian's mobile application terminal.

[0106] While sending the highest-level alarm control information, the main control chip generates a drowning risk status identification record in the event log storage area. The drowning risk status identification record includes a drowning risk identification timestamp, a continuous underwater time count value at the time of drowning risk identification, a Bluetooth Low Energy communication link status identifier, and a highest-level alarm status identifier. The drowning risk status identification record is used for retrospective analysis of the historical process of drowning prevention monitoring and evaluation of system operation logs, providing data basis for subsequent parameter optimization and monitoring strategy adjustment.

[0107] In some specific embodiments, step S500 specifically includes: Step S500.1: Configure multi-level alarm triggering conditions and early warning mode output strategies, and set the triggering of the highest level alarm mode and multi-terminal linkage response mechanism.

[0108] The main control chip's time counter value in continuous water is less than the underwater time threshold parameter for drowning risk assessment. At that time, the intermediate alarm time point threshold is retrieved from the operating parameter storage area. The intermediate alarm time point threshold includes a 30-second intermediate alarm time point and a 40-second intermediate alarm time point. The main control chip performs graded early warning control on the wearer's water stay time based on the count value of the continuous water time counter.

[0109] When the count value of the continuous underwater time counter is greater than or equal to the 30-second mid-alarm time point and less than the 40-second mid-alarm time point, the main control chip calls the execution instruction interface configured inside the main control chip to send low-level optical alarm control information to the waterproof indicator alarm unit, causing the waterproof indicator alarm unit to output an orange low-brightness flashing light signal at a flashing frequency of 0.5Hz. At the same time, the main control chip sends first-level vibration alarm control information to the vibration alarm unit of the guardian's wristband terminal, causing the vibration alarm unit of the guardian's wristband terminal to perform slight vibration and light up the indicator light on the guardian's wristband terminal to remind the wearer that the time spent in the water has been too long.

[0110] When the continuous underwater time counter value is greater than or equal to the 40-second mid-term alarm time and less than the underwater time threshold parameter for drowning risk assessment... At this time, the main control chip calls the execution instruction interface to send medium-level optical alarm control information to the waterproof indicator alarm unit, so that the waterproof indicator alarm unit outputs a yellow medium-brightness flashing light signal at a flashing frequency of 1Hz.

[0111] Simultaneously, the main control chip sends a secondary vibration alarm control message to the vibration alarm unit of the guardian's wristband terminal, causing the vibration alarm unit to perform a moderate-intensity vibration and trigger a combined sound and light alert. The main control chip also sends a medium-level warning message to the information alarm unit of the guardian's mobile application terminal, causing a medium-priority warning notification window to pop up on the display interface of the guardian's mobile application terminal, providing a visual alert that the wearer is approaching a high-risk area for drowning.

[0112] The main control chip detects when the count value of the continuous underwater time counter is greater than or equal to the underwater time threshold parameter for drowning risk assessment. At that time, the underwater time threshold parameter for drowning risk assessment is read from the operating parameter storage area. The values ​​were determined, and the criteria for identifying drowning risk were confirmed. When the drowning risk identification conditions are met, the main control chip uses the execution command interface configured inside the main control chip to send the highest level alarm control information to the waterproof indicator light alarm unit, the guardian's wristband terminal vibration alarm unit, and the guardian's mobile application terminal information alarm unit.

[0113] The main control chip sends the highest-level optical alarm control information to the waterproof indicator light alarm unit, causing the waterproof indicator light alarm unit to output a red high-brightness light signal at a 2Hz flashing frequency. The main control chip also sends the highest-level vibration alarm control information to the vibration alarm unit of the guardian's wristband terminal, causing the vibration alarm unit of the guardian's wristband terminal to perform continuous high-frequency vibrations. Finally, the main control chip sends the highest-level information alarm control information to the information alarm unit of the guardian's mobile application terminal, causing the guardian's mobile application terminal to pop up a red full-screen high-priority notification window on the foreground interface or lock screen interface, and triggering the speaker voice broadcast mechanism and multiple alarm notification paths, including the notification bar message channel and the mobile operating system push service channel, thereby delivering the alarm information of the high risk of drowning to the guardian in the shortest possible time.

[0114] Step S500.2: Configure key monitoring parameters to adapt.

[0115] When any level of alarm event is triggered, the main control chip generates a multi-level alarm event record through the event recording storage area inside the main control chip. The multi-level alarm event record includes the alarm trigger timestamp, the peak value of the continuous underwater time counter at the alarm trigger time, the swimming scene identification information at the time of wearing, the alarm level status identifier, and the Bluetooth Low Energy communication link status snapshot.

[0116] The swimming scene identification information is the scene type information selected and written by the guardian on the guardian's mobile application terminal before the drowning prevention monitoring task begins. The scene type information includes different usage environments such as indoor swimming pool scene, water park scene, and open water scene.

[0117] After generating multi-level alarm event records, the main control chip uses a short-range wireless communication module mounted on a flexible circuit board structure to send the multi-level alarm event records to the guardian's mobile application terminal according to a predetermined data format. The guardian's mobile application terminal stores and lists the multi-level alarm event records in a structured manner in its local cache, allowing the guardian to review each warning event and drowning high-risk alarm event, and analyze and evaluate the existing parameter configuration based on the peak value of the continuous underwater time counter and swimming scene identification information.

[0118] The guardian's mobile application terminal displays the currently set effective ventilation judgment time threshold parameter T1, drowning risk judgment underwater time threshold parameter T2, and graded alarm trigger time point parameters in the parameter adjustment interface. The graded alarm trigger time point parameters include the 30-second intermediate alarm time point and the 40-second intermediate alarm time point.

[0119] The guardian can adaptively adjust the effective breathing time threshold parameter T1, the drowning risk assessment underwater time threshold parameter T2, and the graded alarm triggering time point parameter based on the wearer's age group, swimming skill level, and the water depth and rescue response conditions of the swimming venue.

[0120] After detecting the parameter update command sent by the guardian's mobile application terminal, the main control chip uses the short-range wireless communication module to receive the updated effective breathing time threshold parameter T1, the drowning risk assessment underwater time threshold parameter T2, and the graded alarm trigger time point parameter. It then writes the updated effective breathing time threshold parameter T1, the drowning risk assessment underwater time threshold parameter T2, and the graded alarm trigger time point parameter into the operating parameter storage area. This enables the anti-drowning smart swimming goggles to have scene adaptability and adaptive adjustment capability for protective sensitivity in different wearer groups and different swimming environments, thereby maintaining high accuracy in drowning risk identification and low false alarm rate in various practical use scenarios.

[0121] In some embodiments, the guardian's wristband terminal is equipped with a local timer. When the wristband terminal does not receive any wireless signal from the anti-drowning smart swimming goggles for a continuous time T0, it starts a continuous underwater time count. When a valid exit event packet sent by the swimming goggles is received, the counter is reset. Multi-level alarms are triggered autonomously by the wristband terminal based on the local count value.

[0122] In practical application, the above-mentioned anti-drowning smart swimming goggles include a frame body, a left mirror cavity, a right mirror cavity, and a nose pad connecting the left and right mirror cavities. A flexible circuit board structure is fixedly installed inside the nose pad. A main control chip, a first water immersion electrode, a second water immersion electrode, an impedance detection circuit, and a short-range wireless communication module are soldered onto the flexible circuit board structure. The first and second water immersion electrodes together constitute a dual water immersion electrode. After power-on, the main control chip is configured with a dual water immersion electrode sampling channel and a Bluetooth low-power signal strength sampling channel. The impedance sampling period is set to 20 milliseconds, and the Bluetooth low-power signal strength sampling period is set to... Within 50 milliseconds, the effective ventilation judgment time threshold T1 = 0.8 seconds, the drowning risk judgment underwater time threshold T2 = 45 seconds, the impedance change rate judgment threshold 15 kΩ / s, the Bluetooth low power signal strength step enhancement threshold 10 dB, and the underwater received signal strength indication value threshold −85 dBm are written to the local parameter storage area. At the same time, a state machine management structure and a continuous underwater time counter are constructed. The initial state of the state machine management structure is set to the non-water entry state, the continuous underwater time counter value is set to 0 seconds, and two intermediate alarm time points of 30 seconds and 40 seconds are set in the continuous underwater time counter.

[0123] After initialization, the main control chip controls the dual immersion electrodes to perform periodic impedance signal acquisition. It uses the impedance detection circuit and analog-to-digital conversion module to form an impedance time series. At the same time, it uses the short-range wireless communication module to acquire the received signal strength indication value time series and generate a Bluetooth Low Energy communication link status identifier. In each impedance sampling period, the main control chip reads the current impedance value and the current received signal strength indication value. When the impedance value is less than the 5 kΩ water ingress impedance threshold, the received signal strength indication value is less than the −85 dBm underwater received signal strength indication value threshold, and the Bluetooth Low Energy communication link status identifier indicates a normal connection, the current state field of the state machine management structure is updated from the non-water ingress state to the water ingress state. The counting identifier is activated in the continuous underwater time counter, so that the continuous underwater time counter starts to perform time accumulation according to the unified sampling time base.

[0124] The main control chip detects the impedance change rate parameter in the impedance time series and the change in the received signal strength indicator value in the received signal strength indicator value time series to identify the water exit event when the wearer's head approaches the water surface. When the impedance change rate parameter is greater than 15 kΩ / s and the received signal strength indicator value increases by more than 10 dB in a short period of time, the main control chip updates the current state field of the state machine management structure from the water entry state to the water exit candidate state, starts the water exit duration timer to record the water exit duration. When the water exit duration is greater than or equal to the effective air exchange judgment time threshold T1, the main control chip updates the current state field of the state machine management structure to the effective water exit state and resets the continuous underwater time counter value to 0 seconds. When the water exit duration is less than the effective air exchange judgment time threshold T1, the main control chip restores the current state field of the state machine management structure to the water entry state and keeps the continuous underwater time counter value unchanged to eliminate the interference of brief head-raising behavior on drowning risk identification.

[0125] When the current state field of the state machine management structure is in the water entry state, the main control chip accumulates the continuous water time counter value in 100-millisecond time steps. In each 100-millisecond time step, the continuous water time counter value is increased by 0.1 seconds. During the counting process, the main control chip continuously monitors the Bluetooth Low Energy communication link status and the trend of the received signal strength indicator value. When the Bluetooth Low Energy communication link status indicates a short-term connection interruption, and the impedance change rate parameter does not show a continuous drying trend, and the received signal strength indicator value recovers to above -85dBm in a short time and does not meet the water exit candidate trigger condition, the main control chip maintains the water entry state determination and maintains the original accumulation strategy of the continuous water time counter. This ensures that communication disturbances will not cause the continuous water time counter value to be erroneously cleared to zero, thereby ensuring that the time basis required for drowning risk determination is continuous and reliable.

[0126] The anti-drowning smart swimming goggles are equipped with a waterproof indicator light alarm unit. The guardian's wristband terminal integrates a vibration alarm unit, and the guardian's mobile application terminal integrates an information alarm unit. When the continuous underwater time count is between 30 and 40 seconds, the main control chip sends a low-level optical alarm control message to the waterproof indicator light alarm unit via the execution command interface, causing the waterproof indicator light alarm unit to output a low-brightness orange flashing at a frequency of 0.5Hz. It also sends a level-one vibration alarm control message to the guardian's wristband terminal vibration alarm unit, causing the guardian's wristband terminal vibration alarm unit to perform slight vibration and illuminate the indicator light. When the continuous underwater time count is between 40 seconds and the drowning risk assessment underwater time threshold T2, the main control... The chip sends a medium-level optical alarm control message to the waterproof indicator light alarm unit, causing the waterproof indicator light alarm unit to output a yellow medium-brightness flashing at a frequency of 1Hz. At the same time, it sends a level-two vibration alarm control message to the vibration alarm unit of the guardian's wristband terminal and a medium-level warning message to the information alarm unit of the guardian's mobile application terminal. When the continuous underwater time count value is greater than or equal to the underwater time threshold T2 for drowning risk assessment, the main control chip sends the highest-level alarm control message to the three alarm units, causing the waterproof indicator light alarm unit to output a red high-brightness flashing at a frequency of 2Hz, causing the vibration alarm unit of the guardian's wristband terminal to perform continuous high-frequency vibration, and causing the information alarm unit of the guardian's mobile application terminal to pop up a red full-screen high-priority notification on the foreground interface and lock screen interface and trigger voice broadcast.

Claims

1. A smart swimming goggle for preventing drowning and a method for monitoring drowning prevention therebetween, characterized in that, Includes the following steps: S100: Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, set the terminal pairing and binding and synchronization with the monitoring parameters, initialize the anti-drowning monitoring state machine and continuous underwater time counter, and configure the multi-level alarm module. The multi-level alarm module includes an optical alarm unit mounted on the swimming goggles, a wearable vibration alarm unit paired with the swimming goggles, and a remote information alarm unit. S200: Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value. Based on the received signal strength indication value, identify the water entry status and update the state machine. S300, set the detection window structure and key parameter extraction, set the water effluent candidate event judgment logic, set the effective air exchange judgment and state machine update; S400: Set continuous immersion status confirmation and counter accumulation, execute continuous underwater time accumulation pause and count value reset, set communication abnormality tolerance mechanism and continuous underwater time accumulation error suppression strategy, configure drowning risk judgment underwater time threshold parameter and highest level alarm trigger logic; S500: Configure multi-level alarm triggering conditions and early warning mode output strategies, set the highest level alarm triggering mode and multi-terminal linkage response mechanism, and configure key monitoring parameters to adapt.

2. The anti-drowning smart swimming goggles and its anti-drowning monitoring method according to claim 1, characterized in that, S100 specifically includes: S100.1 Set the structure of the anti-drowning smart swimming goggles, initialize the sampling channel, and set the terminal pairing and binding and synchronization with the monitoring parameters; The anti-drowning smart swimming goggles include a frame body, left and right mirror cavities located on the left and right sides of the frame body, and a nose pad connecting the left and right mirror cavities. A flexible circuit board structure is fixedly installed inside the nose pad. A main control chip, dual water immersion electrodes, a short-range wireless communication module, and an impedance detection circuit electrically connected to the main control chip are sequentially soldered onto the flexible circuit board structure. The dual water immersion electrodes are arranged on the side of the nose pad closest to the wearer's face to form a conductive path with the water and the wearer's facial skin. After the anti-drowning smart swimming goggles are connected to a power source, the main control chip is powered on based on the power supply path provided by the flexible circuit board structure. When powered on, the main control chip first starts the impedance detection circuit that is electrically connected to the dual water immersion electrodes inside the main control chip. The impedance detection circuit is used to periodically collect the impedance of the dual water immersion electrodes. At the same time, the main control chip starts the short-range wireless communication module installed on the flexible circuit board structure. The short-range wireless communication module and the main control chip use a serial communication bus for data interaction. After the main control chip completes the startup of the impedance detection circuit and the short-range wireless communication module, a dual water immersion electrode sampling channel is configured between the dual water immersion electrodes and the main control chip, and a Bluetooth low power signal strength sampling channel is configured between the short-range wireless communication module and the main control chip. After the anti-drowning smart swimming goggles complete the sampling preparation state setting, the main control chip uses the short-range wireless communication module installed on the flexible circuit board structure to search for external terminals. The external terminals include the guardian's wristband terminal and the guardian's mobile application terminal. The guardian's wristband terminal is a wearable terminal worn on the guardian's wrist. The guardian's wristband terminal integrates a short-range wireless communication module and a vibration reminder unit. The guardian's mobile application terminal is a smartphone terminal with the anti-drowning monitoring application installed. The anti-drowning monitoring application is used to configure parameters and display alarm information for the anti-drowning smart swimming goggles. After detecting the guardian's wristband terminal and the guardian's mobile application terminal, the main control chip establishes Bluetooth Low Energy connections with the guardian's wristband terminal and the guardian's mobile application terminal in sequence and completes pairing and binding. After successful pairing and binding, the main control chip first accesses the local parameter storage area inside the main control chip. The main control chip reads key monitoring parameters from the local parameter storage area. When the local parameter storage area does not store key monitoring parameters, the main control chip receives key monitoring parameters from the guardian's mobile application terminal through the short-range wireless communication module and writes the received key monitoring parameters into the local parameter storage area. Key monitoring parameters include: effective ventilation judgment time threshold parameter, drowning risk judgment underwater time threshold parameter, impedance change rate judgment threshold parameter, and Bluetooth Low Energy signal strength step enhancement threshold parameter. S100.2 Initialize the drowning prevention monitoring state machine and the continuous underwater time counter; After the main control chip completes the writing of key monitoring parameters, it builds a state machine management structure inside the main control chip to manage the drowning prevention monitoring process. The state machine management structure is used to distinguish between non-water entry state, water entry state, water exit candidate state, and other drowning prevention monitoring related states. After the state machine management structure is built, the main control chip sets the initial state of the state machine management structure to the non-water entry state, so that the drowning prevention smart swimming goggles are in the non-water entry monitoring state by default during the initial stage of wearing. The anti-drowning smart swimming goggles are equipped with a multi-level alarm module, which includes a waterproof indicator light alarm unit, a vibration alarm unit for the guardian's wristband terminal, and an information alarm unit for the guardian's mobile application terminal. During subsequent anti-drowning monitoring, the multi-level alarm module executes graded alarms based on the count value of the continuous underwater time counter and the underwater time threshold parameter for determining the drowning risk. After the main control chip completes the initialization of the state machine management structure, the preset alarm time points of the multi-level alarm module, and the initialization of the continuous underwater time counter, it sets the current working state of the anti-drowning smart swimming goggles to the state where impedance acquisition, Bluetooth low power signal strength acquisition, and anti-drowning monitoring logic can be executed.

3. The anti-drowning smart swimming goggles and its anti-drowning monitoring method according to claim 1, characterized in that, S200 specifically includes: S200.1 Configure impedance signal acquisition and impedance change rate calculation, set up communication link acquisition, and process the received signal strength indication value; After the main control chip sets the current working state of the anti-drowning smart swimming goggles to the state of being able to perform impedance acquisition, Bluetooth low power signal strength acquisition and anti-drowning monitoring logic, the main control chip starts to perform the real-time acquisition process of impedance signals based on the dual water immersion electrode sampling channel. The dual water immersion electrodes consist of a first water immersion electrode and a second water immersion electrode. Both the first water immersion electrode and the second water immersion electrode are fixedly installed on the lower inner side of the flexible circuit board structure inside the nose pad and are arranged towards the wearer's face and the water. The first water immersion electrode and the second water immersion electrode are electrically connected to the main control chip through wires, forming a closed impedance sampling loop between the first water immersion electrode and the second water immersion electrode. The main control chip uses an impedance detection circuit to amplify the acquired raw analog voltage signal and uses an analog-to-digital converter module to convert the raw analog voltage signal into a digital voltage sampling value. The main control chip calculates the corresponding impedance value based on the digital voltage sampling value and the constant excitation current value, forming an impedance time series. Within each sliding time window, the main control chip calculates the impedance change rate parameter based on the impedance value at the end of the current time window and the impedance value at the end of the previous time window. While the main control chip performs impedance signal acquisition and impedance change rate calculation, the main control chip uses the Bluetooth Low Energy signal strength sampling channel to collect the Bluetooth Low Energy communication link status between the anti-drowning smart swimming goggles and the guardian's wristband terminal in real time. The main control chip acquires the received signal strength indication value in the short-range wireless communication module and records the received signal strength indication value as... The strength value is maintained by the main control chip in its internal storage space. The time series of received signal strength indication values ​​composed of strength values ​​is used to characterize the wireless channel attenuation characteristics between the guardian's wristband terminal and the anti-drowning smart swimming goggles; After completing the sliding average processing, the main control chip quantifies the current Bluetooth Low Energy (BLE) communication link status by combining whether a connection interruption event has occurred in the BLE communication link, and forms a Bluetooth Low Energy (BLE) communication link status identifier. S200.

2. Water entry status identification and state machine update based on received signal strength indication value; After obtaining the impedance time series, impedance change rate parameter, received signal strength indication value time series, and Bluetooth Low Energy communication link status identifier, the main control chip makes a comprehensive judgment on whether the wearer is in water. In each impedance sampling cycle, the main control chip executes the water entry status identification logic based on three conditions: First, the current impedance value is less than the 5 kΩ water entry impedance threshold represented by the water entry impedance threshold parameter; second, the current received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter; third, the current Bluetooth Low Energy communication link status indicator indicates that the Bluetooth Low Energy communication link is in a normal connection state, and the received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter in multiple consecutive sampling cycles. When the current impedance value is less than the 5 kΩ water impedance threshold represented by the water ingress impedance threshold parameter, the current received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter, and the current Bluetooth Low Energy communication link status indicator indicates that the Bluetooth Low Energy communication link is in a normal connection state, and the received signal strength indication value is less than the -85 dBm underwater received signal strength threshold represented by the underwater received signal strength indication value threshold parameter in multiple consecutive sampling periods, the main control chip updates the current state field in the state machine management structure from the non-water ingress state to the water ingress state, and sets the counting activation flag bit in the continuous underwater time counter to the active state, so that the continuous underwater time counter starts to accumulate the continuous underwater time of the wearer in the fully submerged state at a preset time step.

4. The anti-drowning smart swimming goggles and its anti-drowning monitoring method according to claim 1, characterized in that, The S300 specifically includes: S300.1, Set the detection window structure and key parameter extraction, and set the logic for judging water effluent candidate events; When the main control chip is in the "water entry" state in the state machine management structure, a detection window structure is configured in the internal running storage area of ​​the main control chip. This detection window structure is used to extract and calculate the impedance change rate parameter and the received signal strength indication value within a fixed time period. The time period of the detection window structure is denoted as... Length of time The value is set to That is, 300 milliseconds; Within the time interval corresponding to each detection window structure, the main control chip extracts the impedance change rate parameter at the end of the detection window based on the impedance time series and the impedance change rate calculation expression. Within the detection window structure, the main control chip simultaneously performs endpoint differential calculations on the time series of the received signal strength indication value, extracting the change in received signal strength within the corresponding time interval of the detection window structure. ; After extracting the impedance change rate parameter and the received signal strength change, the main control chip retrieves the impedance change rate judgment threshold parameter and the Bluetooth Low Energy signal strength step enhancement threshold parameter from the main control chip's operating parameter storage area. The value of the impedance change rate judgment threshold parameter is set as follows: The value of the Bluetooth Low Energy signal strength step enhancement threshold parameter is set as follows: The impedance change rate threshold parameter is used to identify the rapid thinning of the water film on the surface of the first and second water immersion electrodes. The Bluetooth Low Energy signal strength step enhancement threshold parameter is used to identify the rapid enhancement of the received signal strength after the anti-drowning smart swimming goggles cross the water interface. At the end of the time interval corresponding to each detection window structure, the main control chip determines the candidate water effluent event according to two conditions: the impedance change rate parameter at the end of the current detection window structure satisfies the following relationship: The change in received signal strength corresponding to the current detection window structure satisfies the following relationship: When both the impedance change rate parameter determination condition and the received signal strength change determination condition are met; The main control chip updates the current state field in the state machine management structure from the water inlet state to the water outlet candidate state, and builds a water outlet duration timer inside the main control chip. The water outlet duration timer is used to record the continuous time length from the start of the water outlet candidate state to the end of the water outlet state. When the water outlet duration timer is built, the count value is initialized to 0 seconds. S300.2, Set effective ventilation judgment and state machine update, identify invalid water discharge events and roll back the water state; When the state machine management structure is in the water outlet candidate state, the main control chip initiates the effective air exchange determination logic. The main control chip pre-writes the effective air exchange determination time threshold parameter in the local parameter storage area. The effective air exchange determination time threshold parameter is denoted as... The effective ventilation determination time threshold parameter is set as follows: When the main control chip is in the water discharge candidate state, it continuously monitors the water discharge duration timer count, Bluetooth Low Energy communication link status indicator and received signal strength indicator. When all three conditions are met, the main control chip determines the current water expulsion behavior as a valid ventilation behavior: the Bluetooth Low Energy communication link status indicator shows that the Bluetooth Low Energy communication link between the anti-drowning smart swimming goggles and the guardian's wristband terminal is in a stable connection state; the received signal strength indicator value remains continuously within the water expulsion signal strength range during the water expulsion candidate state, with a typical value range of −75dBm to −65dBm; and the count value of the water expulsion duration timer is greater than or equal to the valid ventilation determination time threshold parameter. That is, satisfying the relation: , The current water discharge duration recorded by the water discharge duration timer; If any situation occurs during the operation of the water discharge duration timer while the main control chip is in the water discharge candidate state of the state machine management structure, the main control chip will determine the current water discharge behavior as invalid. The situations include: the water discharge duration recorded by the water discharge duration timer is less than the effective ventilation determination time threshold parameter. ,Right now The received signal strength indicator value falls back into the underwater received signal strength range defined by the underwater received signal strength indicator value threshold parameter within the continuous sampling period. The typical value of the underwater received signal strength indicator value threshold parameter is -85dBm and below. The impedance value between the first and second water-immersed electrodes was detected to drop rapidly again in a short period of time through impedance time series and impedance change rate parameters. This indicates that the first and second water-immersed electrodes are completely covered by water again. Invalid water-out behavior usually corresponds to the wearer briefly raising their head, local body parts briefly emerging from the water, or struggling movements, which cannot provide the wearer with sufficient breathing and ventilation process.

5. The anti-drowning smart swimming goggles and its anti-drowning monitoring method according to claim 1, characterized in that, The S400 specifically includes: S400.1 Set continuous immersion status confirmation and counter accumulation, and execute continuous water time accumulation pause and count value reset; When the current state field of the state machine management structure is in the water immersion state, the main control chip uses the short-range wireless communication module to collect the Bluetooth Low Energy communication link status identifier and confirms whether the wearer is continuously in a fully submerged state based on the time series of the received signal strength indicator value. The main control chip calls the underwater received signal strength indicator value threshold parameter in the local parameter storage area. The value of the underwater received signal strength indicator value threshold parameter is set to −85dBm. The underwater received signal strength indicator value threshold parameter is used as the basis for confirming the fully submerged state. When the Bluetooth Low Energy (BLE) link status indicator indicates that the BLE link is in a connection interruption state, or when the received signal strength indicator value is lower than the underwater received signal strength indicator value threshold parameter of −85dBm for multiple consecutive sampling periods, the main control chip determines that the wearer is currently in a state of continuous immersion in water. When the current state field of the main control chip in the state machine management structure is in the water discharge candidate start state or the effective water discharge state, the count value accumulation operation of the continuous water time counter is paused. The water discharge candidate start state and the effective water discharge state are generated by the main control chip in the water discharge event detection and effective air exchange determination module after the state machine is switched by combining the impedance change rate parameter and the change of the received signal strength indication value. The main control chip calls the effective ventilation judgment time threshold parameter in the local parameter storage area. The value of the effective ventilation judgment time threshold parameter is set to 0.8 seconds. The main control chip judges the effective ventilation based on the water outlet duration recorded by the water outlet duration timer. When the water outlet duration recorded by the water outlet duration timer is greater than or equal to the effective ventilation judgment time threshold parameter, the main control chip sets the current state field of the state machine management structure to the effective water outlet state and resets the count value of the continuous water time counter to 0 seconds. S400.2, Set up a communication anomaly tolerance mechanism and a continuous underwater time accumulation error suppression strategy, and configure the underwater time threshold parameter for drowning risk assessment and the highest level alarm triggering logic; The main control chip introduces a communication anomaly tolerance mechanism and a continuous water time accumulation error suppression strategy during the continuous water time accumulation process, and analyzes and processes short-term anomalies in the Bluetooth Low Energy communication link. During the sampling period when the Bluetooth Low Energy communication link status indicator indicates a short-term connection interruption, the main control chip continuously analyzes the impedance time series and the recovery trend of the received signal strength indicator value. When the main control chip detects that the impedance change rate parameter continues to show a trend of changing towards dryness, or the received signal strength indicator value recovers to above -85dBm in a short time but does not meet the conditions for judging the water outflow candidate event, the main control chip keeps the current state field of the state machine management structure unchanged, continues to maintain the judgment of the water inflow state or the effective water outflow state, and keeps the continuous water time counter in the water maintaining the original accumulation strategy. The communication anomaly tolerance mechanism and the continuous underwater time accumulation error suppression strategy smooth out the transient data anomalies caused by Bluetooth Low Energy communication link disturbances. The main control chip reads the continuous water time counter value in real time. When the continuous water time counter value is greater than or equal to the risk judgment threshold, the chip will detect the time counter value. At that time, the main control chip determined that the wearer was in a high-risk drowning state.

6. The anti-drowning smart swimming goggles and its anti-drowning monitoring method according to claim 1, characterized in that, The S500 specifically includes: S500.1 Configure multi-level alarm triggering conditions and early warning mode output strategies, and set the triggering of the highest level alarm mode and multi-terminal linkage response mechanism; The main control chip's time counter value in continuous water is less than the underwater time threshold parameter for drowning risk assessment. When the intermediate alarm time point threshold is called from the operating parameter storage area, the intermediate alarm time point threshold includes a 30-second intermediate alarm time point and a 40-second intermediate alarm time point. The main control chip performs graded early warning control on the wearer's water stay time based on the count value of the continuous water time counter. The main control chip detects when the count value of the continuous underwater time counter is greater than or equal to the underwater time threshold parameter for drowning risk assessment. At that time, the underwater time threshold parameter for drowning risk assessment is read from the operating parameter storage area. The values ​​were determined, and the criteria for identifying drowning risk were confirmed. When the drowning risk identification conditions are met, the main control chip uses the execution instruction interface configured inside the main control chip to send the highest level alarm control information to the waterproof indicator alarm unit, the guardian wristband terminal vibration alarm unit, and the guardian mobile application terminal information alarm unit respectively. S500.2, Configure key monitoring parameters to adapt; When any level alarm event is triggered, the main control chip generates a multi-level alarm event record through the event recording storage area inside the main control chip. The multi-level alarm event record includes the alarm trigger timestamp, the peak value of the continuous underwater time counter at the alarm trigger time, the swimming scene identification information at the time of wearing, the alarm level status identifier, and the Bluetooth Low Energy communication link status snapshot. After generating multi-level alarm event records, the main control chip uses a short-range wireless communication module installed on a flexible circuit board structure to send the multi-level alarm event records to the guardian's mobile application terminal in a predetermined data format. The guardian's mobile application terminal stores and lists the multi-level alarm event records in a structured manner in the local cache, so that the guardian can review each warning event and drowning high-risk alarm event, and analyze and evaluate the existing parameter configuration based on the peak value of the continuous underwater time counter and the swimming scene identification information. The guardian can adaptively adjust the effective breathing time threshold parameter T1, the drowning risk assessment underwater time threshold parameter T2, and the graded alarm triggering time point parameter based on the wearer's age group, swimming skill level, and the water depth and rescue response conditions of the swimming venue.

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