Deep skin anti-wrinkle beauty instrument applying graphene electrothermal effect and control method

Abstract

The invention relates to the technical field of graphene, and discloses a deep skin anti-wrinkle beauty instrument applying a graphene electrothermal effect and a control method, the method comprises the following steps: pre-activating a graphene electrothermal film to obtain a negative temperature coefficient resistance characteristic parameter; performing contact state detection and multi-parameter analysis on the target area to obtain personalized temperature control parameters; pWM sectional power control is carried out on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters, and a staged heating temperature output strategy is obtained; real-time feedback adjustment is carried out based on a staged heating temperature output strategy, and a stable temperature control signal is obtained; the graphene electrothermal film is subjected to gradual cooling power adjustment according to the stable temperature control signal, meanwhile, the safe stop state of the beauty instrument is confirmed, the unique characteristic that the resistance value is reduced when the temperature of the graphene material rises is utilized, and compared with a traditional linear resistance material, the temperature control precision and the response speed are higher.

Description

Technical Field

[0001] The present invention relates to the technical field of graphene, and particularly to a deep skin anti-wrinkle beauty device applying the electrothermal effect of graphene and a control method thereof. Background Art

[0002] Traditional electrothermal beauty devices mostly use metal wires or ceramic materials as heating elements, and stimulate the regeneration of skin collagen through the warming effect, so as to achieve the effect of improving skin relaxation and fine lines.

[0003] However, there are still many technical defects in the existing electrothermal beauty devices in actual applications. The resistance-temperature relationship of traditional electrothermal materials shows a linear change, making it difficult to achieve precise temperature control, and problems such as local overheating or uneven temperature are likely to occur, affecting the nursing effect and possibly causing discomfort to the skin. Most existing devices adopt a single-point contact detection method, and cannot accurately identify multi-dimensional information such as contact area and pressure distribution, resulting in a lack of personalization in the temperature control strategy and being difficult to adapt to different users' skin characteristics. In addition, the temperature control of traditional devices mostly adopts a simple on-off mode or linear voltage regulation method, lacking an intelligent feedback regulation mechanism and being unable to perform dynamic optimization according to real-time temperature changes. Summary of the Invention

[0004] The present invention provides a deep skin anti-wrinkle beauty device applying the electrothermal effect of graphene and a control method thereof. The present invention utilizes the unique characteristic that the resistance value of graphene material decreases when the temperature rises, and has higher temperature control accuracy and response speed compared with traditional linear resistance materials, improving the safety and comfort during use.

[0005] The first aspect of the present invention provides a control method for a deep skin anti-wrinkle beauty device applying the electrothermal effect of graphene. The control method for the deep skin anti-wrinkle beauty device applying the electrothermal effect of graphene includes: Pre-activate the graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters; Detect the contact state and perform multi-parameter analysis on the target area to obtain personalized temperature control parameters; Based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters, perform PWM segmented power control on the graphene electrothermal film to obtain a phased heating temperature output strategy; Perform real-time feedback regulation based on the phased heating temperature output strategy to obtain a stable temperature control signal; According to the stable temperature control signal, perform progressive cooling power regulation on the graphene electrothermal film, and at the same time confirm the safe stop state of the beauty device.

[0006] Combined with the first aspect, in the first implementation manner of the first aspect of the present invention, the pre-activation of the graphene electrothermal film to obtain the negative temperature coefficient resistance characteristic parameters includes: Applying an excitation voltage pulse signal within a preset voltage range to the graphene electrothermal film and collecting stable conductance state data; Performing real-time monitoring of the resistance value change of the stable conductance state data to obtain a dynamic resistance value sequence of the graphene electrothermal film during the pre-activation process; Based on the dynamic resistance value sequence and the corresponding temperature data, performing resistance-temperature characteristic curve modeling to obtain a negative temperature coefficient resistance model; Based on the negative temperature coefficient resistance model, performing parameter extraction to obtain negative temperature coefficient resistance characteristic parameters including a reference resistance value, a temperature coefficient, and a response time constant.

[0007] Combined with the first aspect, in the second implementation manner of the first aspect of the present invention, the contact state detection and multi-parameter analysis of the target area to obtain personalized temperature control parameters includes: Based on the capacitance value changes of each induction electrode in the multi-point capacitive induction electrode array, performing real-time monitoring of the target area to obtain capacitance change data of each induction electrode; According to the capacitance change data of each induction electrode and a preset capacitance threshold, performing effective contact determination to obtain effective contact electrode distribution information; Based on the capacitance value differences between different induction electrodes in the effective contact electrode distribution information, performing contact parameter calculation to obtain contact area distribution data and contact pressure distribution data; According to the contact area distribution data and the contact pressure distribution data, performing multi-parameter analysis on the target area to obtain personalized temperature control parameters.

[0008] Combined with the first aspect, in the third implementation manner of the first aspect of the present invention, the multi-parameter analysis of the target area according to the contact area distribution data and the contact pressure distribution data to obtain personalized temperature control parameters includes: Based on the contact area distribution data and the contact pressure distribution data, performing regional characteristic detection on the target area to obtain multi-dimensional regional characteristic data; According to the multi-dimensional regional characteristic data, performing type classification to obtain a regional type recognition result; Based on the regional type recognition result, querying a personalized temperature control database to obtain basic temperature control parameters; According to the basic temperature control parameters and the contact area distribution data, performing temperature correction to obtain personalized temperature control parameters.

[0009] Combined with the first aspect, in the fourth implementation manner of the first aspect of the present invention, the PWM segmented power control of the graphene electrothermal film based on the personalized temperature control parameter and the negative temperature coefficient resistance characteristic parameter to obtain a staged heating temperature output strategy includes: Calculate the PWM basic control parameter according to the personalized temperature control parameter and the negative temperature coefficient resistance characteristic parameter, and the PWM basic control parameter includes the control frequency and the duty cycle adjustment range; Based on the PWM basic control parameter, perform segmented duty cycle setting for the preheating stage, the stable heating stage and the heat preservation stage to obtain the PWM duty cycle control sequence corresponding to each heating stage; Establish a non-linear response relationship between the power and temperature of the graphene electrothermal film according to the negative temperature coefficient resistance characteristic parameter to obtain power-temperature response relationship data; Based on the PWM duty cycle control sequence and the power-temperature response relationship data, perform an analysis of the staged temperature output strategy for the graphene electrothermal film to obtain a staged heating temperature output strategy.

[0010] Combined with the first aspect, in the fifth implementation manner of the first aspect of the present invention, the establishment of a non-linear response relationship between the power and temperature of the graphene electrothermal film according to the negative temperature coefficient resistance characteristic parameter to obtain power-temperature response relationship data includes: Based on the reference resistance value and the temperature coefficient in the negative temperature coefficient resistance characteristic parameter, analyze the resistance change law of the graphene electrothermal film in different temperature ranges to obtain temperature range resistance change curve data; Conduct an analysis of the reverse mapping relationship between resistance and temperature according to the temperature range resistance change curve data to obtain a temperature calculation model for reverse calculating temperature through the resistance value; Based on the temperature calculation model, perform real-time power calculation to obtain a power output numerical sequence corresponding to different temperature ranges; Perform non-linear fitting according to the power output numerical sequence to obtain power-temperature response relationship data of the non-linear response relationship between the power and temperature of the graphene electrothermal film.

[0011] Combined with the first aspect, in the sixth implementation manner of the first aspect of the present invention, the real-time feedback adjustment based on the staged heating temperature output strategy to obtain a stable temperature control signal includes: Based on a multi-level temperature monitoring system, synchronously collect the self-temperature, the contact surface temperature of the target area and the ambient temperature of the graphene electrothermal film to obtain multi-channel temperature feedback data; Perform multi-sensor data fusion according to the multi-channel temperature feedback data to obtain fusion temperature monitoring data; Perform PID control based on the fused temperature monitoring data and the target temperature in the staged heating temperature output strategy to obtain temperature deviation control parameters including proportional deviation, integral deviation, and differential deviation; Dynamically adjust the PWM control parameters of the graphene electrothermal film according to the temperature deviation control parameters to obtain a stable temperature control signal.

[0012] Combined with the first aspect, in the seventh implementation manner of the first aspect of the present invention, the progressive cooling power adjustment of the graphene electrothermal film according to the stable temperature control signal while confirming the safe stop state of the beauty device includes: Based on the stable temperature control signal, judge the end timing of the temperature change trend and usage time of the target area to obtain end timing judgment data; Perform progressive PWM duty cycle decreasing control on the graphene electrothermal film according to the end timing judgment data to obtain a PWM decreasing control sequence; Perform multiple safety protection state detections based on the PWM decreasing control sequence to obtain safety state monitoring data including temperature overheat protection, contact abnormality protection, and time limit protection; Confirm the stop state according to the safety state monitoring data and the condition that the temperature of the target area returns to the ambient temperature range to obtain the safe stop state of the beauty device.

[0013] Combined with the first aspect, in the eighth implementation manner of the first aspect of the present invention, the progressive PWM duty cycle decreasing control of the graphene electrothermal film according to the end timing judgment data to obtain a PWM decreasing control sequence includes: Determine the initial PWM duty cycle based on the temperature stability evaluation index in the end timing judgment data to obtain the initial PWM duty cycle value for progressive cooling and the target cooling rate parameter; Calculate the decreasing interval time and decreasing amplitude according to the initial PWM duty cycle value and the target cooling rate parameter to obtain a PWM decreasing control strategy including time interval and decreasing percentage; Generate a duty cycle decreasing time sequence based on the PWM decreasing control strategy to obtain PWM time sequence decreasing data with the duty cycle value gradually decreasing at a preset time interval; Set the total duration and termination conditions of the cooling process according to the PWM time sequence decreasing data to obtain a PWM decreasing control sequence.

[0014] The second aspect of the present invention provides a deep - skin anti - wrinkle beauty device applying the graphene electrothermal effect, and the deep - skin anti - wrinkle beauty device applying the graphene electrothermal effect includes: A pre-activation module for pre-activating a graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters; A contact state detection module for detecting the contact state and performing multi-parameter analysis on a target area to obtain personalized temperature control parameters; A power control module for performing PWM segmented power control on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters to obtain a staged heating temperature output strategy; A real-time feedback adjustment module for performing real-time feedback adjustment based on the staged heating temperature output strategy to obtain a stable temperature control signal; A cooling power adjustment module for performing progressive cooling power adjustment on the graphene electrothermal film according to the stable temperature control signal and simultaneously confirming the safe stop state of the beauty instrument.

[0015] Compared with the prior art, the present invention has the following beneficial effects: By establishing the negative temperature coefficient resistance characteristic parameters of the graphene electrothermal film and utilizing the unique property that the resistance value of the graphene material decreases when the temperature rises, the present invention realizes an accurate control method for inversely calculating the temperature by monitoring the change of the resistance value in real time, and has higher temperature control accuracy and response speed compared with traditional linear resistance materials. By adopting a multi-point distributed capacitive induction electrode array, multi-dimensional information such as the contact area, pressure distribution, and contact angle can be detected simultaneously. Compared with the existing single-point contact detection technology, the accuracy and comprehensiveness of contact state recognition are significantly improved, providing a reliable data basis for subsequent personalized control. By performing multi-parameter analysis on the target area and establishing a personalized temperature control database based on contact characteristics, the temperature parameters can be automatically adjusted according to different skin types and characteristics, realizing the technical leap from the traditional fixed temperature mode to the intelligent personalized control mode. By using pulse width modulation technology to perform segmented power control on the graphene electrothermal film and through the refined management of the preheating stage, stable heating stage, and heat preservation stage, the advantages of rapid heating and accurate temperature control of the graphene material are fully exerted, and it has higher energy efficiency and control accuracy compared with the traditional linear voltage regulation method. By establishing a multi-level temperature monitoring system and adopting multi-sensor data fusion and PID control algorithms, the real-time monitoring and dynamic adjustment of the temperature control process are realized, effectively avoiding the temperature fluctuation problem in the traditional on-off control mode and ensuring the stability of the temperature during the nursing process. By judging the intelligent end timing and controlling the PWM duty cycle to decrease, a smooth transition from the nursing temperature to the ambient temperature is realized, avoiding the discomfort caused by the sudden stop of heating of traditional equipment. At the same time, multiple safety protection mechanisms are integrated, significantly improving the safety and comfort during use. Description of the Drawings

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical substance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in the present invention.

[0018] Figure 1 is a schematic flowchart of a control method for a deep - skin anti - wrinkle beauty instrument applying the graphene electro - thermal effect provided by an embodiment of the present invention; Figure 2 is a schematic block diagram of the structure of a deep - skin anti - wrinkle beauty instrument applying the graphene electro - thermal effect provided by an embodiment of the present invention. Detailed Embodiments

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0020] The flowchart shown in the drawings is only an example, and does not necessarily include all content and operations / steps, nor does it necessarily execute in the described order. For example, some operations / steps can be decomposed, combined, or partially merged. Therefore, the actual execution order may change according to the actual situation.

[0021] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0022] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations. Please refer to Figure 1, an embodiment of the control method of a deep - skin anti - wrinkle beauty instrument applying the graphene electro - thermal effect in an embodiment of the present invention includes: Step 100: Pre - activate the graphene electro - thermal film to obtain negative temperature coefficient resistance characteristic parameters; It can be understood that the execution subject of the present invention can be a deep - skin anti - wrinkle beauty instrument applying the graphene electro - thermal effect, or a terminal or a server. Specifically, it is not limited here. An embodiment of the present invention takes the server as the execution subject for illustration.

[0023] Specifically, apply a set of excitation voltage pulse signals within a preset voltage range to the graphene electro - thermal film. The voltage range is controlled between 0.5V and 1.2V, the pulse frequency is set between 50Hz and 100Hz, and it lasts for 3 seconds to 5 seconds to ensure that the carbon atom lattice structure inside the graphene material gradually tends to a stable conductance state during the excitation process. In this state, the graphene material exhibits an obvious enhanced carrier migration characteristic, manifested as the resistance gradually tending to a dynamic equilibrium range. To capture the microscopic conductive changes in this process, simultaneously start the integrated high - precision resistance detection circuit to monitor the resistance value changes presented by the graphene electro - thermal film during the application of the excitation in real - time, collect its complete conductance conversion trajectory, and obtain a sequence of dynamic resistance values formed over time. This sequence of dynamic resistance values is synchronously collected with the temperature data of the surrounding environment, and based on their correspondence, a joint analysis is performed to establish a resistance - temperature relationship model for the graphene electro - thermal film during the pre - activation process. In the specific modeling process, considering the negative temperature coefficient characteristic of the graphene material, that is, in the typical skin - care temperature range of 25°C to 65°C, an increase in temperature will cause a significant decrease in the material resistance. This non - linear change law is essentially different from the positive temperature coefficient behavior of traditional metal or ceramic electro - thermal elements. Therefore, modeling techniques such as multi - segment fitting or non - linear least - squares regression are used to associate the sequence of dynamic resistance values with the synchronous temperature data, generate a resistance - temperature characteristic curve that accurately reflects the physical response characteristics of the graphene material, and encapsulate this curve into a negative temperature coefficient resistance model. Through mathematical analysis and statistical regression analysis of this model, multiple key parameters are extracted, including the reference resistance value R0 of the graphene material in the unheated state, the resistance change rate per unit temperature change, that is, the temperature coefficient α, and the time - characteristic quantization index of the system response to the steady state, that is, the response time constant τ, finally forming the negative temperature coefficient resistance characteristic parameters.

[0024] Step 200: Detect the contact state and perform multi - parameter analysis on the target area to obtain personalized temperature control parameters; Specifically, based on the multi - point capacitive induction electrode array deployed on the surface of the beauty instrument head, the array adopts a 3×3 or 4×4 grid structure, each electrode is made of copper foil with a thickness of 0.1mm - 0.2mm, and the unit area is 2mm2 To 4 mm 2 , and are precisely arranged at intervals of 5 mm - 8 mm. When the beauty device comes into contact with the human skin, the dielectric properties of human tissues will cause the capacitance values sensed by each induction electrode to change. Therefore, the capacitance change data of each induction electrode during the contact process is collected in real time and continuously input into a capacitance detection circuit with high-speed sampling. This circuit has a detection accuracy at the 0.1 pF level and can capture tiny contact change trends. The original capacitance change data is compared point by point with a set capacitance change threshold. The preset effective contact judgment threshold is 0.5 pF to 1.0 pF. When the capacitance value increment of a certain electrode exceeds this range, it is determined that an effective skin contact has occurred. Through this mechanism, the system can quickly identify which electrodes are in an effective contact state at present, thus obtaining a two-dimensional spatial distribution map composed of multiple effective contact points, that is, the effective contact electrode distribution information. Based on this distribution information, the capacitance value differences between electrodes are analyzed. This difference reflects the tiny height differences and pressure distribution characteristics on the contact surface. Therefore, by using the method of multi-electrode comparison calculation and combining the gradient trend of capacitance change, a contact parameter model is constructed to obtain two key variables: contact area distribution data and contact pressure distribution data. Among them, the size of the contact area is obtained by multiplying the number of effective electrodes by the unit electrode area, and the contact pressure is calculated based on the spatial gradient of the capacitance change amplitude of each electrode. The larger the capacitance value, the stronger the pressing force. Multi-parameter analysis is performed on the target area according to the contact area distribution data and contact pressure distribution data. By comprehensively evaluating the continuity, uniformity of the contact area and the stability of the pressure center distribution, it is determined whether the contact is good, and based on the relationship between the concentration of the pressure distribution and the skin sensitive area, it is judged whether it is necessary to locally adjust the heating power. At this time, the system calls a personalized temperature adjustment model associated with the contact area and pressure characteristics, and dynamically sets core temperature control parameters such as the upper temperature limit value, heating rate, and heat preservation time based on the existing user data and default skin characteristic data, so as to output personalized temperature control parameters suitable for the current skin contact state.

[0025] Detect the regional characteristics of the target area based on the contact area distribution data and the contact pressure distribution data. Divide the target contact area into multiple local sub-areas, each sub-area is covered by a number of capacitive induction electrodes, and calculate the corresponding local characteristic indexes based on the induction intensity and pressure gradient information of the electrodes in each sub-area. Specifically, the system evaluates the area integrity, pressure uniformity, edge contact stability, and central pressure peak position of each sub-area respectively, thereby generating a multi-dimensional regional characteristic data set, which reflects the geometric composition of the contact state and reflects the dynamic stability and physical form distribution of the skin contact surface. Through feature engineering processing and clustering analysis of the above multi-dimensional regional characteristic data, combined with the regional type classification model trained by machine learning, each sub-area is identified and labeled to determine which standard regional type it belongs to, such as typical types like "high-pressure concentration type", "wide and uniform type", "edge sliding type", or "low-pressure unstable type". This classification not only reflects the physical form pattern of the current skin-instrument contact, but also implies the heat resistance ability, sensitivity level of the skin in this area, and its appropriate heat load level. Through the classification and recognition mechanism, the physical characteristics are effectively corresponded with the temperature control behavior to form a clear regional type recognition result. After identifying the type of the target area, call the built-in personalized temperature control database, which has pre-established the corresponding relationship between different regional types and basic temperature control parameters based on skin type, regional contact mode, and clinical heat response data. The basic temperature control parameters include key control variables such as the target temperature range (such as 38°C - 42°C), heating rate (such as 1°C per minute), and heat preservation duration. When the system obtains the temperature control parameters matching the current regional type through query, in order to improve the temperature control accuracy, perform temperature correction operations on these parameters in combination with the actual contact area data. The correction algorithm is adjusted according to the correlation between the contact area and the temperature transfer efficiency. For example, when the actual contact area is significantly smaller than the regional standard value, reduce the initial heating rate and the upper limit of the target temperature to avoid heat concentration or skin irritation caused by insufficient contact; on the contrary, when it is detected that the contact area is sufficient and the pressure distribution is uniform, appropriately increase the target temperature level and extend the constant temperature time to improve the heat penetration depth and nursing effect. Obtain personalized temperature control parameters.

[0026] Step 300, perform PWM segmented power control on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters to obtain a staged heating temperature output strategy; Specifically, the personalized temperature control parameters are integrated with the negative temperature coefficient resistance characteristic parameters extracted from the graphene material in the pre-activation stage to establish a PWM basic control framework that can respond to skin differences and material nonlinear behaviors. In this process, the temperature control parameters set for the target area include the target temperature value, heating rate, insulation duration, etc., combined with the resistance change curve, temperature coefficient and response time constant of the graphene electric heating film, to derive the matching PWM basic control parameters, mainly including the control frequency and duty cycle adjustment range. In order to ensure the balance between the adjustment accuracy and the response speed, the control frequency is set between 1kHz and 5kHz, and the duty cycle range is between 10% and 90%, forming a heating power regulation domain with adjustable resolution. Based on the PWM basic control parameters, the heating process is divided into three stages according to the personalized temperature control curve, namely the preheating stage, the stable heating stage and the insulation stage, and the corresponding duty cycle interval is set according to the heat demand of each stage. The preheating stage requires that the temperature of the graphene electric heating film be quickly raised to about 80% of the target temperature. At this time, the duty cycle should be set in the high-energy zone of 70%-90%; after entering the stable heating stage, in order to avoid the risk of thermal burns caused by excessive temperature rise, the duty cycle is reduced to the middle range of 40%-60% to achieve the temperature slowly approaching the target value; and in the insulation stage, the duty cycle is reduced to 20%-40%, forming a platform area for dynamic temperature maintenance, ensuring that the temperature fluctuation is controlled within ±0.5℃, thereby improving thermal comfort and consistency of care. The PWM duty cycle control sequence of each stage needs to be dynamically recursively combined with the time stepping algorithm, so that the entire heating process is both in line with physiological thermal adaptability and has stable heat output characteristics. After the staged PWM control logic is set, the nonlinear response relationship between power and temperature of the graphene electric heating film is established according to the pre-extracted negative temperature coefficient resistance characteristic parameters. This response relationship comprehensively considers the resistance change trend of graphene in different temperature zones, that is, as the temperature rises, its resistance gradually decreases, resulting in an increase in current under constant voltage input, thus forming a nonlinear effect of power increase. Therefore, by jointly deducing the resistance-temperature model and the voltage-current relationship, a power-temperature response data table containing the actual temperature output under different input powers is generated. Based on the PWM duty cycle control sequence and the power-temperature response relationship data, the graphene electric heating film is analyzed in stages. The power output is dynamically adjusted according to the duty cycle set in each stage, and the temperature change curve of the graphene electric heating film surface and the skin contact area under the current power is calculated in real time. If it is found that the heating rate is lower than the set personalized heating rate, the system temporarily increases the duty cycle within a safe range to compensate; on the contrary, when the temperature surge trend is too fast, it is quickly suppressed by shortening the duty cycle period, so as to ensure that the temperature output of each stage is highly consistent with the personalized control target. Finally, a staged heating temperature output strategy is generated, which describes the PWM duty cycle required for each stage, the corresponding time length, the predicted temperature curve and the adjustment rules.

[0027] Based on the negative temperature coefficient resistance characteristic parameters of the graphene electrothermal film, especially the two core variables of the reference resistance value and the temperature coefficient, a full-range model of the resistance change with temperature of graphene within the target temperature control range is established, and the resistance change curve data in the temperature range is generated. This curve reflects the basic physical law that the resistance of the graphene material will decrease non-linearly with the increase of temperature, and shows different change rates in different temperature regions, that is, the resistance decreases significantly in the lower temperature region, while the resistance change tends to be gentle when approaching the upper limit of the target temperature. Based on the above resistance change curve in the temperature range, a resistance-temperature inverse mapping modeling analysis is carried out. By the actual resistance value of the graphene electrothermal film collected at any known moment, the temperature value corresponding to the current film surface is inversely calculated. In order to maximize the mapping accuracy, a temperature calculation model with high fitting accuracy and strong robustness to input perturbations is constructed. Methods such as polynomial regression, piecewise exponential fitting or spline interpolation are used to numericalize the inverse function relationship between the resistance value and the temperature, and it is built into the temperature monitoring and feedback control module to achieve real-time temperature estimation. This model allows the system to identify the temperature region where the current heating state is located in real time only based on the resistance measurement results in the situation where there is no direct temperature sensor involved, providing an immediate basis for the response adjustment of the control strategy. On the basis of obtaining a stable and reliable temperature calculation model, the actual power output of the graphene electrothermal film in each temperature range is calculated using Ohm's law and the power formula, that is, the power output level in the current heating stage is calculated by collecting the applied voltage and the measured resistance value. Since the resistance of the graphene electrothermal film changes significantly with temperature, under the condition of a fixed voltage, its power output shows a strong temperature dependence, which reflects the non-linear thermal response characteristics of this material. By continuously calculating the power values at multiple temperature points and constructing the original numerical sequence of the temperature-power relationship, the asymmetric and non-uniform growth trend of the power with the increase of temperature is depicted. Especially in the preheating and heat preservation boundary regions, its response speed and power dissipation change are particularly sensitive. The discrete power output numerical sequence is input into the fitting algorithm to construct a non-linear curve, and the response function describing the power-temperature relationship of the graphene electrothermal film is obtained, that is, the power-temperature response relationship data.

[0028] Step 400: Perform real-time feedback adjustment based on the staged heating temperature output strategy to obtain a stable temperature control signal; Specifically, during the actual operation of the beauty instrument, three types of key temperature information, namely the self-temperature of the graphene electrothermal film, the skin contact surface temperature of the target area, and the current ambient temperature, are synchronously collected based on the multi-level temperature monitoring system. Among them, the self-temperature of the graphene film is obtained by a high-sensitivity platinum resistance sensor integrated inside the film body, with a response time less than 0.1 second and an accuracy of ±0.2°C; the skin contact surface temperature is detected by a distributed NTC thermistor array, and each sensor covers 2 cm2 The area is used to obtain the spatial distribution characteristics of the surface temperature; the ambient temperature is measured in real time by an independent external temperature sensor and is used to perform ambient compensation and correction to eliminate the interference of external temperature changes on the system judgment. The above-mentioned multi-channel temperature signals are respectively sent into the central control processing unit through high-sampling-rate channels to form a temperature feedback data set. Before the data enters the feedback control module, multi-sensor data fusion processing is performed on the temperature feedback data from multiple temperature sensing sources. The weighted average algorithm is used in combination with the time-window sliding mean and outlier rejection mechanism to smooth and correct the fluctuations caused by different sensors due to contact quality, response speed, or noise interference, forming high-confidence fusion temperature monitoring data. Calculate the difference between the fusion temperature monitoring data and the current target temperature in the staged heating temperature output strategy, and based on this, execute the PID control algorithm to construct a temperature deviation control parameter group. In the PID calculation process, the proportional term represents the direct response intensity of the current temperature deviation and is used to quickly adjust the power output direction; the integral term is used to accumulate the history of temperature differences, correct long-term offset phenomena, and avoid the accumulation of static errors; the derivative term reflects the temperature change trend and can perform predictive suppression during temperature mutations or severe fluctuations to prevent overshoot or oscillation of the temperature control system. Specifically, the proportion deviation, integral deviation, and derivative deviation calculated in real time are combined through weighting to form an immediate comprehensive temperature regulation output coefficient, and the PID parameter group (such as Kp, Ki, Kd) is dynamically corrected according to the actual control target to adapt to the thermal response inertia characteristics of the graphene electrothermal film and the upper limit of skin thermal sensitivity. After obtaining the temperature deviation control parameters, use them as adjustment instructions to input into the PWM control module, and dynamically adjust the PWM signal parameters of the graphene electrothermal film, mainly including key control elements such as duty cycle, cycle frequency, and waveform smoothness. For example, when the detected temperature is low and the deviation value increases, appropriately increase the duty cycle to enhance the power output, and when the temperature approaches the upper limit or there is a rapid upward trend, reduce the PWM duty cycle or even have short intermittent pulses to ensure that the heating curve tends to be stable, thereby avoiding the risks of thermal shock and overheating. Through the closed-loop adjustment mechanism, finally output a temperature control signal that is updated in real time, dynamically optimized, and highly stable.

[0029] Step 500: Perform progressive cooling power adjustment on the graphene electrothermal film according to the stable temperature control signal, and at the same time confirm the safe stop state of the beauty device.

[0030] Specifically, based on the current heating state reflected by the stable temperature control signal, the temperature change trend of the target area is continuously evaluated in the time domain and numerical domain. By calculating the maintenance time of the skin contact surface temperature within the stable section and the overall usage duration, and combining the slope and fluctuation range of the temperature change curve, it is determined whether the optimal end time of the nursing process has been reached. If the system detects that the target temperature has been continuously and stably maintained for more than the set duration (such as 5 minutes), and the total usage duration is close to the upper limit (such as 15 to 20 minutes), end time judgment data is generated as the trigger condition for the cooling control logic. According to the above judgment results, a progressive duty cycle decreasing strategy is implemented for the PWM control parameters of the graphene electrothermal film. Specifically, within a preset time window (such as every 30 seconds), the PWM duty cycle is gradually decreased by 10% or a fixed ratio, so that the heating power gradually weakens in a non-abrupt form, forming a temperature control curve with a smooth attenuation of heat output. This PWM decreasing control sequence ensures a slow transition of the temperature gradient between the skin surface and the deep layer, avoiding both the temperature drop stimulation caused by sudden heating stop and helping to maintain the integrity of the microcirculation heat diffusion process, providing buffer conditions for the penetration and absorption of the thermal effect. At the same time, a multiple safety protection status detection mechanism is synchronously started to monitor the key safety indicators during the cooling process in real time, ensuring full protection capabilities throughout the power reduction period. At this time, three core parameters are detected: the first is temperature overheat protection, that is, if any local temperature monitoring point shows a local rise and exceeds the safety upper limit (such as 50 °C), all PWM outputs are immediately interrupted and an over-temperature alarm is triggered; the second is contact abnormality protection, that is, if the induction electrode detects an unstable skin contact state, such as a sudden pressure change or a sharp reduction in the contact area, the system will judge it as a disconnection state and enter the end process in advance; the third is time limit protection, that is, when the actual heating time exceeds the maximum allowable value (such as 20 minutes), regardless of the current temperature state, the system will also be forced to enter the stop stage. These protection mechanisms jointly generate safety status monitoring data as an important constraint basis for determining whether it is safe to exit the power delivery process. In the final stage when power reduction and safety monitoring are carried out simultaneously, an environmental matching judgment is made on the actual temperature change of the target area, that is, based on the comparison between the real-time temperature feedback data and the environmental temperature value. When it is detected that the skin surface temperature has dropped to the range of the environmental temperature ±2 °C and remains stable for a period of time (such as 30 to 60 seconds), the system determines that the temperature has basically returned to the natural state and the heat output effect has ended. Subsequently, according to this condition and the previously generated safety status monitoring data, a logical cross-verification is performed. If all safety conditions are met, it is confirmed that the beauty device reaches a safe stop state. According to the confirmation result, all PWM output channels are closed, and at the same time, the key data of this nursing process are recorded, including the usage duration, heating stability, contact quality score, and the cooling process curve, etc., and it automatically enters the standby state.

[0031] By integrating the time stability index, the analysis result of the fluctuation amplitude, and the average calorific value trend curve in the temperature data, it is confirmed that the current state is a thermally stable platform. Based on this, the initial PWM duty cycle value for progressive cooling is set, usually between 20% and 40%. At the same time, combined with the user's skin thermal sensitivity and the built-in physiological heat buffer model of the system, a target cooling rate parameter is set, and the recommended range is about 1℃ per minute decrease to ensure that the skin is not stimulated by sudden temperature changes. Calculate the decreasing interval time and decreasing amplitude according to the initial PWM duty cycle value and the target cooling rate parameter. This process is modeled based on the thermal inertia response characteristics of the skin and the power-temperature non-linear relationship of the graphene material, so as to derive a control strategy in which the time interval and the decreasing percentage are coupled with each other. The time interval is set to 30 seconds to 45 seconds, and the decreasing amplitude is set using a linear or exponential decay curve. For example, the duty cycle is decreased by 5% every 30 seconds or decays exponentially from the initial value to the lowest power holding state. In this way, a PWM decreasing control strategy is constructed, in which the decrease amplitude and interval of each stage are automatically adjusted based on the heat release balance and the temperature response change rate. Generate the time-sequential decreasing data of the PWM duty cycle according to the above control strategy, forming a PWM control signal sequence that continuously decreases as time progresses. This time sequence follows the aforementioned time and amplitude decreasing rules, and at the same time, the feedback effect of the duty cycle change on the actual temperature curve is monitored in real time to ensure that the skin surface temperature indeed shows a corresponding downward trend after each decrease, and there is no temperature rebound or system hysteresis. This time sequence control logic is maintained in real time through the built-in time stepper and feedback correction module to achieve dynamic tracking and fine-tuning, thereby ensuring the temperature control stability and user comfort during the entire cooling process. Based on the PWM time-sequential decreasing data, set the termination trigger mechanism according to the set target total duration of the cooling process (such as 3 to 5 minutes) and the ambient temperature convergence judgment condition. When it is detected that the skin surface temperature has stably dropped within ±2℃ of the ambient temperature, or the total cooling time has reached the set maximum duration, and the trend stability of all temperature sensing points meets the termination standard, the system automatically determines that the cooling process is completed, outputs the PWM decreasing control sequence, and stops all heating control instructions. At the same time, this control sequence is saved as part of the temperature control record for reference when used next time, realizing the continuous optimization of the personalized cooling strategy.

[0032] In the embodiments of the present invention, the present invention establishes the negative temperature coefficient resistance characteristic parameters of the graphene electrothermal film. By utilizing the unique characteristic that the resistance value of the graphene material decreases when the temperature rises, an accurate control method for inversely calculating the temperature by real-time monitoring of the resistance value change is realized, which has higher temperature control accuracy and response speed compared with traditional linear resistance materials. The multi-point distributed capacitive sensing electrode array can simultaneously detect multi-dimensional information such as contact area, pressure distribution, and contact angle. Compared with the existing single-point contact detection technology, it significantly improves the accuracy and comprehensiveness of contact state recognition, providing a reliable data basis for subsequent personalized control. By performing multi-parameter analysis on the target area and establishing a personalized temperature control database based on contact characteristics, the temperature parameters can be automatically adjusted according to different skin types and characteristics, realizing the technical leap from the traditional fixed temperature mode to the intelligent personalized control mode. The pulse width modulation technology is used to perform segmented power control on the graphene electrothermal film. Through the refined management of the preheating stage, stable heating stage, and heat preservation stage, the advantages of rapid heating and accurate temperature control of the graphene material are fully exerted, which has higher energy efficiency and control accuracy compared with the traditional linear voltage regulation method. A multi-level temperature monitoring system is established, and multi-sensor data fusion and PID control algorithm are adopted to realize the real-time monitoring and dynamic adjustment of the temperature control process, effectively avoiding the temperature fluctuation problem in the traditional switch control mode and ensuring the stability of the temperature during the nursing process. Through the intelligent end timing judgment and the decreasing control of the PWM duty cycle, a smooth transition from the nursing temperature to the ambient temperature is realized, avoiding the discomfort caused by the sudden stop of heating of traditional devices. At the same time, multiple safety protection mechanisms are integrated, significantly improving the safety and comfort during use.

[0033] In a specific embodiment, the process of executing step 100 may specifically include the following steps: Apply an excitation voltage pulse signal within a preset voltage range to the graphene electrothermal film and collect the stable conductance state data; Perform real-time resistance value change monitoring on the stable conductance state data to obtain the dynamic resistance value sequence of the graphene electrothermal film during the pre-activation process; Based on the dynamic resistance value sequence and the corresponding temperature data, establish a resistance-temperature characteristic curve model to obtain a negative temperature coefficient resistance model; Based on the negative temperature coefficient resistance model, perform parameter extraction to obtain the negative temperature coefficient resistance characteristic parameters including the reference resistance value, temperature coefficient, and response time constant.

[0034] Specifically, a set of low-power pre-excitation voltage pulse signals adapted to the graphene film electrothermal structure are designed. The voltage range is controlled between 0.5V and 1.2V, the excitation frequency is set between 50Hz and 100Hz, and the pulse action time is maintained within the range of 3 to 5 seconds to avoid lattice transient damage or heat accumulation. The excitation signal has a certain volatility to stimulate the rearrangement of the carrier migration path in the carbon-carbon covalent bond network system inside the graphene, so that it enters a dynamic conductance self-adjustment state below a low stable threshold in the initial conductive state. This state is manifested as the resistance rapidly drops to a certain stable interval under high-frequency low-amplitude pulse excitation, and the convergence of the resistance value fluctuation is enhanced, that is, the system conductance tends to be stable. During the process of completing voltage excitation and stabilizing the conductance behavior, a parallel high-precision resistance detection path is started, and the voltage-current data collected in real time at both ends of the graphene electrothermal film are processed in equal time segments, and the change of the resistance value per unit time is calculated to generate a complete dynamic resistance value sequence. To ensure the resistance detection accuracy, a high-resolution ADC module (at least 12 bits or more) and an operational amplifier structure with high common-mode rejection ratio and low temperature drift characteristics are used, and each measured resistance value is paired and stored with the ambient temperature data or the detection value of the infrared non-contact temperature probe at the corresponding moment, so as to realize the data pairing logic of one-to-one correspondence between the resistance value and the temperature. This sequence will show the non-linear variation law of the resistance of the graphene material with temperature. Especially in the range of 25°C to 65°C, which is the comfortable skin contact range for the human body, its resistance shows a downward trend with the increase of temperature, that is, it exhibits a negative temperature coefficient (NTC) characteristic, in contrast to the positive temperature coefficient (PTC) effect of traditional metal wires or ceramic heating elements. Characteristic modeling is carried out on the paired data of the dynamic resistance value sequence and temperature, that is, a resistance-temperature relationship curve is constructed. The fitting modeling of this curve uses non-linear fitting methods such as exponential function, hyperbolic function or piecewise polynomial function to capture the difference in the response slope of the graphene resistance in different temperature intervals. In particular, there is usually an obvious change rate turning point in the section from 30°C to 45°C and the section from 45°C to 65°C. To improve the generality of the model, the spline interpolation algorithm is used for local fitting, and the least squares optimization method is used to globally converge and correct the overall curve residual, forming a high-precision fitting curve reflecting the non-linear variation of the graphene electrothermal film resistance with temperature, and constructing its mathematical mapping model to support subsequent temperature inversion and power regulation. After completing the curve modeling, deep parameter extraction is carried out on this negative temperature coefficient resistance model.The reference resistance value is obtained by analyzing the tangent line of the temperature-resistance curve at the room temperature point (25 °C). This value is used to represent the initial resistance of the graphene electrothermal film under unpowered conditions or in an ambient static state, and is the standard reference point for calculating the relative change amplitude of the subsequent resistance. Secondly, by performing piecewise differential calculation on the average slope of the curve in each temperature region, the temperature coefficient α is obtained, that is, the resistance change rate caused by a unit temperature change. In order to describe the speed of the response of the graphene electrothermal film during the transition from one steady state to another, the time constant τ of the exponential fitting curve of the resistance change process is analyzed, and a first-order inertial system model is used for fitting, and the response time constant is extracted therefrom. This time constant reflects the response delay ability of the material to an external thermal excitation signal. The smaller the value, the faster the heating response, which is used for the feedforward adjustment part in the dynamic control algorithm. The reference resistance value, the temperature coefficient, and the response time constant are encapsulated into a negative temperature coefficient resistance characteristic parameter set, which serves as the underlying physical support template for subsequent PWM duty cycle calculation, PID regulation gain optimization, and temperature estimation back-calculation algorithm, and allows for dynamic update and compensation through periodic self-excitation according to the aging state of the electrothermal film material during long-term use.

[0035] In a specific embodiment, the process of executing step 200 may specifically include the following steps: Based on the capacitance value changes of each induction electrode in the multi-point capacitive induction electrode array, the target area is monitored in real time to obtain the capacitance change data of each induction electrode. According to the capacitance change data of each induction electrode and a preset capacitance threshold, an effective contact determination is made to obtain effective contact electrode distribution information. Based on the capacitance value differences between different induction electrodes in the effective contact electrode distribution information, contact parameter calculations are performed to obtain contact area distribution data and contact pressure distribution data. According to the contact area distribution data and the contact pressure distribution data, multi-parameter analysis is performed on the target area to obtain personalized temperature control parameters.

[0036] Specifically, based on a multi-point capacitive induction electrode array distributed on the working surface of the beauty device, the contact state of the target skin area is monitored in real time. These induction electrodes are made of highly conductive copper foil or silver paste materials. The area of a single electrode is between 2 and 4 square millimeters, and the electrode spacing is maintained between 5 millimeters and 8 millimeters to form a stable spatial density. The array is arranged in the form of 3×3, 4×4 or higher dimensions, so as to cover the entire skin contact surface on a two-dimensional plane and form multi-point parallel detection channels. When the user brings the beauty device close to the skin and makes physical contact with the skin surface, due to the fact that human tissues have a higher dielectric constant than air, the capacitance values of local electrode pairs will change significantly, especially manifested as a rapid increase in capacitance. On this basis, the system activates a high-sensitivity capacitive sampling circuit to rapidly collect and synchronously record the capacitance values presented by each electrode at different time points, forming an original capacitance change data set. This data is input into the main control unit through a high-speed ADC module and a differential detection front end. The control system tracks the change trend of the capacitance value with millisecond-level time accuracy, and compares the current capacitance value of each collected electrode with its reference capacitance value in the initial startup state to calculate the absolute change value ΔC. The ΔC is compared with a preset capacitance threshold (between 0.5 pF and 1.0 pF) obtained through multiple usage experiences and user skin model training. If the ΔC of a certain electrode exceeds this threshold, it is considered that the electrode has been effectively contacted by the skin and is thus marked as an "effectively contacted electrode". By counting the positions of all electrodes in the entire array that meet the contact determination conditions, an effectively contacted electrode distribution map at the current moment is generated. Contact parameter calculation is performed based on the capacitance value differences between different induction electrodes in the effectively contacted electrode distribution information. Since the change in capacitance value not only reflects whether contact occurs but also has a certain sensitivity to contact pressure, especially in the skin fitting area, due to different contact angles, skin elasticity, and pressure magnitudes between different electrodes, there will be significant differences in the capacitance value increase amplitudes. Therefore, by extracting the amplitude of ΔC of each electrode and establishing a spatial gradient model, two types of parameters, namely contact area distribution and contact pressure distribution, are derived. The estimation of the contact area is based on the product of the number of effectively contacted electrodes and the unit electrode area as the basic model, and at the same time, the concentration and shape of the contact are analyzed by combining the capacitance differences between the boundary electrodes and the central electrodes; while the contact pressure distribution forms a heat map based on the normalized values of ΔC of each contacted electrode, and by analyzing indicators such as the concentration, maximum value position, and change gradient of the high-capacitance change area, it is judged whether there are complex states such as overpressure, bias pressure, or light contact in a certain area of the skin. Multi-dimensional parameter analysis is performed on the current target area based on the contact area distribution data and the contact pressure distribution data to judge the quality, stability, and safety of the contact behavior, and personalized temperature control parameters adapted to this contact state are derived. The system calls the built-in temperature control strategy database, which has pre-trained a large number of regular models on the skin's response to temperature under different contact areas and pressure patterns through machine learning means.For example, if the contact area is large and the pressure is evenly distributed, the system sets the target temperature in the medium-high range (e.g., 42°C to 45°C) and the heating rate to 1.2°C / min to 1.5°C / min to fully penetrate the dermis layer; conversely, if the contact area is small and the pressure is concentrated in a single area, the system will lower the target temperature to 38°C to 40°C and limit the heating rate to below 0.8°C / min to avoid discomfort caused by heat concentration; for scenarios where the pressure is extremely uneven or there is edge drift in the contact area, the system will delay the start of the heating behavior, prioritize contact correction prompts or adjust the activation strategy of the electrothermal film partition to effectively avoid the risk of local overheating. In addition, by comparing the current contact characteristics with the user's historical usage records, if the user has shown sensitive reactions or discomfort behaviors under similar contact characteristics, protection corrections will be further set on the temperature control parameters, such as reducing the constant temperature maintenance time, increasing the cooling interval time, or limiting the maximum temperature platform height.

[0037] In a specific embodiment, the process of performing the step of multi-parameter analysis on the target area according to the contact area distribution data and the contact pressure distribution data to obtain personalized temperature control parameters may specifically include the following steps: Perform regional characteristic detection on the target area based on the contact area distribution data and the contact pressure distribution data to obtain multi-dimensional regional characteristic data; Perform type classification according to the multi-dimensional regional characteristic data to obtain a regional type recognition result; Query the personalized temperature control database based on the regional type recognition result to obtain basic temperature control parameters; Perform temperature correction according to the basic temperature control parameters and the contact area distribution data to obtain personalized temperature control parameters.

[0038] Specifically, based on the contact area distribution data and the contact pressure distribution data, local spatial characteristics of the target skin area are analyzed. This process starts with the effective contact point set detected by a two-dimensional electrode matrix. By calculating the area boundary shape, center point position, edge smoothness, area dispersion degree, and local contact density within each contact area, a morphological feature vector reflecting the geometric composition is generated. At the same time, heat map interpolation processing and gradient vector field extraction operations are performed on the contact pressure distribution to obtain mechanical feature dimensions such as the spatial change trend of contact intensity, local pressure concentration, and overall pressure uniformity. On this basis, all these geometric and mechanical features are combined to form multi-dimensional regional characteristic data, including at least seven core indicators such as area integrity, pressure peak position, pressure center offset rate, edge pressure gradient, local concentration coefficient, area variance coefficient, and boundary stability. Each indicator corresponds to a physical quantity description of the heat acceptance ability and skin response ability of the contact area. After obtaining the complete regional characteristic data, the trained regional recognition and classification model is called to perform intelligent type discrimination on the current target area. This model is constructed based on support vector machine, multi-layer perceptron, or convolutional neural network architecture, and its training set covers the regional response feature annotations under various typical contact states, such as "high-pressure concentration type", "wide-area uniform type", "edge sliding type", "local drift type", "light touch unstable type", etc. Each type corresponds to a temperature control adaptation mode. By inputting the currently detected feature vector into the model, the system outputs the category label of the current target area and its confidence level, forming a clear regional type recognition result. For example, when it is detected that the pressure concentration is extremely high, the area is small, and the pressure peak point is far from the geometric center, the system determines it as the "high-pressure concentration type", which means that there are risks such as concentrated skin force and blood return obstruction in this area, and the temperature rise rate needs to be carefully controlled; if the system identifies it as the "wide-area uniform type", it indicates that the contact area is complete and the pressure is uniform, and a conventional temperature curve is suitable and the heating efficiency can be ensured. According to the regional type recognition result, the system accesses the preset personalized temperature control database, which stores the basic temperature control strategy parameters corresponding to different types of areas under the standard skin state. Each type of area corresponds to a set of basic temperature control parameter sets, including the target temperature upper limit value, heating rate, heat preservation time interval, and temperature change tolerance. For example, for the "edge sliding type", the target temperature is limited within 38°C, the heating rate is controlled at 0.5°C / minute, and the contact stability evaluation time needs to be increased as a pre-heating delay; for the "wide-area uniform type", the target temperature is set at 42°C, the heating rate is 1.2°C / minute, and the heat preservation duration is more than 10 minutes. The system directly retrieves the basic temperature control parameters of this area according to the recognition result and uses them as the first-level input variables for thermal control decision-making. To ensure that the set temperature control strategy fully matches the current real-time contact state, a correction mechanism for the contact area distribution is introduced on the basis of the basic temperature control parameters.This correction mechanism calculates the correction coefficient based on the proportion of the currently detected contact area in the total effective array area, the central distribution structure of the contact area, and the historical change trend of the contact area, so as to adjust the target temperature or the heating rate. For example, when the system finds that the current contact area meets the uniform contact mode but the overall proportion is low (such as less than 30% of the total array area), the upper limit of the temperature is moderately lowered by within 2°C, and the heating stage is extended to 150% of the default duration to prevent skin burning caused by concentrated heat flux. On the contrary, if the area proportion is extremely high and the centrality of the contact distribution is strong, the system slightly increases the duty cycle in the initial heating stage without changing the total temperature target to improve the overall temperature reaching speed. The system also combines the user's historical sensitivity level, skin type label, and temperature control feedback during the previous care process for fine-tuning compensation, and finally forms the personalized temperature control parameters required for the current area.

[0039] In a specific embodiment, the process of executing step 300 may specifically include the following steps: Calculate the PWM basic control parameters according to the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters, where the PWM basic control parameters include the control frequency and the duty cycle adjustment range; Based on the PWM basic control parameters, set the segmented duty cycle for the preheating stage, the stable heating stage, and the heat preservation stage to obtain the PWM duty cycle control sequence corresponding to each heating stage; Establish the non-linear response relationship between the graphene electrothermal film power and temperature according to the negative temperature coefficient resistance characteristic parameters to obtain the power-temperature response relationship data; Based on the PWM duty cycle control sequence and the power-temperature response relationship data, analyze the staged temperature output strategy of the graphene electrothermal film to obtain the staged heating temperature output strategy.

[0040] Specifically, the PWM basic control parameters are calculated based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters. The personalized temperature control parameters are jointly generated by the front-end skin contact behavior recognition module, the regional characteristic classification algorithm, and the temperature correction module, and specifically include information such as the target temperature value, the heating rate, the constant temperature maintenance time, and the skin sensitivity correction coefficient. The negative temperature coefficient resistance characteristic parameters of the graphene heating film include the reference resistance value, the temperature coefficient α, and the response time constant τ. These parameters jointly describe the overall trend of the material resistance changing non-linearly with temperature and the dynamic response ability. During the calculation process of the PWM basic control parameters, the coupling matching between the temperature control target and the power response of the graphene material is considered. By combining the temperature coefficient α with the reference resistance value, the resistance change amplitude is inversely deduced according to the target temperature range, and then the target power level is estimated in combination with the voltage input range of the heating film and mapped into the PWM control space. The PWM control frequency is selected in the range of 1 kHz to 5 kHz to balance the temperature control sensitivity and the system response inertia, while the PWM duty cycle adjustment range covers the complete heat output range between 10% and 90%. On this basis, combined with the personalized heating rate and the expected heating time, the change gradient and the initial boundary of the PWM signal in each stage are limited. According to the above PWM basic control parameters, the entire heating process is processed in stages and divided into a preheating stage, a stable heating stage, and a heat preservation stage, and a corresponding PWM duty cycle interval is set for each stage. In the preheating stage, in order to quickly increase the temperature from the ambient level to 80% of the target temperature, the duty cycle is set in a higher interval, such as 70%-90%. The duration of this stage is calculated according to the set heating rate and can be dynamically corrected. In the stable heating stage, the duty cycle is adjusted to the middle section of 40%-60% to make the temperature slowly approach and approach the target value. The duration of this stage is 30 seconds to 1 minute and is linked in real time with the resistance change trend. The heat preservation stage is a constant temperature output state, and the duty cycle is further reduced to between 20%-40% and dynamically fine-tuned to ensure that the heat output can adapt to the skin heat diffusion effect and maintain a stable temperature control result. This entire process forms a set of staged PWM duty cycle control sequences, and each stage corresponds to a PWM duty cycle time window structure and an adjustment gradient function. While generating the control signal, a temperature-power response relationship model is established for the graphene heating film material itself as the basis for heat output calculation. According to the negative temperature coefficient characteristic of graphene, its resistance decreases as the temperature rises. Therefore, under the condition of a fixed voltage input, its current increases, and the power output shows a non-linear increasing relationship. Using the resistance change trend constructed by the temperature coefficient and the reference resistance, combined with the actual voltage application parameters of the system, the power output at different temperature points is calculated, and a non-linear power-temperature response data table is generated through continuous data fitting. To improve the real-time calculation ability of the system, this response relationship is stored as power-temperature response relationship data in the temperature control system in a discrete look-up table manner and combined with the response time constant to form a power response delay compensation model.Based on the PWM duty cycle control sequence and the power-temperature response relationship data, a phased temperature output strategy analysis is carried out for the graphene electrothermal film. In each heating stage, the output power is calculated according to the current PWM duty cycle value, and the current predicted temperature is mapped through the non-linear power model, and then the difference analysis is carried out with the target temperature curve. If the predicted temperature is lower than the expected value, the duty cycle is moderately increased. If it is higher than the expected value, the signal duty cycle is decreased. At the same time, the control gradient is dynamically adjusted according to the temperature change slope to ensure the smoothness of temperature control. In the heat preservation stage, the temperature fluctuation amplitude is detected. If it is found that the skin temperature fluctuation exceeds the range of ±0.5 °C, the duty cycle is quickly fine-tuned through the feedback mechanism to prevent the temperature control from becoming unstable. During the actual output process, the current, voltage and resistance data are collected in real time, and they are inversely substituted into the temperature model for dynamic inversion of the temperature to improve the timeliness and response accuracy of temperature detection. The system outputs a phased heating temperature output strategy.

[0041] In a specific embodiment, the process of performing the step of establishing the non-linear response relationship between the power and temperature of the graphene electrothermal film according to the negative temperature coefficient resistance characteristic parameters to obtain the power-temperature response relationship data may specifically include the following steps: Based on the reference resistance value and the temperature coefficient in the negative temperature coefficient resistance characteristic parameters, the resistance change law analysis is carried out on the graphene electrothermal film in different temperature intervals to obtain the resistance change curve data of the temperature interval; According to the resistance change curve data of the temperature interval, the resistance-temperature reverse mapping relationship analysis is carried out to obtain the temperature calculation model for inversely calculating the temperature through the resistance value; Based on the temperature calculation model, real-time power calculation is carried out to obtain the power output numerical sequence corresponding to different temperature intervals; According to the power output numerical sequence, non-linear fitting is carried out to obtain the power-temperature response relationship data of the non-linear response relationship between the power and temperature of the graphene electrothermal film.

[0042] Specifically, utilize the material resistance temperature response characteristic data obtained during the pre-activation stage of the electrothermal film, especially the two key parameters of the reference resistance value and the temperature coefficient contained therein. The reference resistance value is the stable-state resistance value obtained through a high-precision resistance sampling module at the initial ambient temperature before the graphene material is thermally excited, representing the intrinsic conductivity of the material in the unexcited state; while the temperature coefficient reflects the amplitude of the resistance change of the material under a unit temperature change and is an important parameter determining the thermal response speed and intensity of graphene. Based on these two fundamental physical quantities, numerical modeling is performed on the resistance change law of the graphene electrothermal film in different temperature ranges. Considering that the graphene material exhibits an obvious negative temperature coefficient characteristic in the temperature range related to skin contact from 25°C to 65°C, this range is subdivided into four sub-sections, such as 25°C to 35°C, 35°C to 45°C, 45°C to 55°C, and 55°C to 65°C. The resistance change trend is collected within each section, and the corresponding relationship between the resistance value and temperature is analyzed. Since the resistance of the graphene electrothermal film does not decrease uniformly in a linear manner but is jointly affected by factors such as the microscopic carbon atom arrangement, carrier migration speed, and material thermal inertia, the resistance decrease speed shows a non-uniform characteristic with different change rates in different temperature regions. Through point-by-point calculation and trend smoothing fitting of the resistance measurement data in each sub-interval, a complete resistance change curve for the temperature range is plotted, thereby constructing the original data framework of the material temperature response. According to the resistance-temperature reverse mapping relationship analysis of the resistance change curve data for the temperature range, that is, using the resistance value as the input variable to output the current temperature range of the material. By establishing a data look-up table structure or using an interpolation function, the previously obtained resistance change curve for the temperature range is mathematically processed so that each actually detected resistance value can find the corresponding temperature value in the response table. If the resistance value is between two known temperature range points, the system automatically performs linear interpolation or spline interpolation to obtain a relatively smooth and continuous temperature output, forming a complete temperature calculation model and embedding it in the temperature control main control module to support the temperature reverse deduction function in the subsequent PWM closed-loop control logic. With the help of the above temperature calculation model, the temperature estimation is quickly completed for the resistance data collected at any moment, and based on this, the real-time power calculation is performed. Considering that the graphene electrothermal film operates in a constant-voltage power supply mode during operation, its instantaneous power output will be mainly dominated by the change of the resistance value. Since the material has a negative temperature coefficient characteristic and the resistance value decreases with the increase of temperature, the system can observe a trend of asymmetric increase in power during the temperature change process. To accurately capture the dynamic characteristics of the power, the resistance value deduced for each corresponding temperature point and the applied constant driving voltage are input into the power estimation model to calculate the output power at this temperature point in real time. Repeat this process to cover all temperature regions to obtain a power output numerical sequence containing different temperature points and corresponding power output values, reflecting the power change trend of the graphene electrothermal film in the entire operating temperature range.Perform non-linear fitting based on the power output numerical sequence to construct a continuous response function between the power and temperature of the graphene electrothermal film. Use methods such as polynomial fitting, exponential function fitting, or piecewise high-order curve approximation to reconstruct the curve of the data sequence, and at the same time select the optimal function expression form through residual evaluation and goodness-of-fit judgment. This function model not only needs to accurately fit the data trend, but also must have a certain first-order derivative continuity, so that its slope can be used as the gain reference for temperature regulation in PID control or other closed-loop regulation mechanisms. The finally obtained fitting function constitutes the core data model of the non-linear response relationship between the power and temperature of the graphene electrothermal film, and is encapsulated in the form of a table, function, or structure inside the system.

[0043] In a specific embodiment, the process of executing step 400 may specifically include the following steps: Synchronously collect the self-temperature, the contact surface temperature of the target area, and the ambient temperature of the graphene electrothermal film based on the multi-level temperature monitoring system to obtain multi-channel temperature feedback data; Perform multi-sensor data fusion based on the multi-channel temperature feedback data to obtain fused temperature monitoring data; Perform PID control based on the fused temperature monitoring data and the target temperature in the staged heating temperature output strategy to obtain temperature deviation control parameters including proportional deviation, integral deviation, and differential deviation; Dynamically adjust the PWM control parameters of the graphene electrothermal film according to the temperature deviation control parameters to obtain a stable temperature control signal.

[0044] Specifically, synchronously collect the self-temperature, the contact surface temperature of the target area, and the ambient temperature of the graphene electrothermal film based on the multi-level temperature monitoring system. This architecture consists of three parts: one is a micro temperature sensor integrated inside the graphene electrothermal film, which is deployed on the heating film material body and is used to collect the internal thermal state of the heating source in real time. Its response time is less than 0.1 second, and the measurement accuracy reaches ±0.2 °C. It is mainly used to judge whether the heating area is uniform, whether there is a hot spot offset or a local over-temperature trend; the other is a group of thermistor arrays arranged on the contact surface between the beauty instrument and the skin. The coverage area of each thermal sensing element is about 2 cm 2, precisely monitor the temperature distribution at different positions on the skin surface. The data in this part reflects the effect of the heat flow actually felt by the user and is an important basis for adjusting comfort. Thirdly, an independent ambient temperature sensor module is set at a position on the beauty device far from the heat source to collect the temperature change information of the current external air in real time. It is mainly used to perform ambient compensation and correction on the contact surface temperature to eliminate false temperature rise or fall signals caused by external interference. These three types of sensors together constitute the multi-channel temperature feedback channel of the system. In the data acquisition link, through the synchronous sampling mechanism, each sensing node is aligned with the same timestamp to form a set of sequential sampling data including internal temperature, surface temperature, and ambient temperature, obtaining multi-channel temperature feedback data. According to the multi-channel temperature feedback data, multi-sensor data fusion is performed to generate unified fusion temperature monitoring data. This fusion process uses multi-sensor data fusion algorithms, including weighted average processing, time window sliding average, Kalman filtering, outlier removal, and data fitting and reconstruction, etc. Appropriate weights are assigned to each temperature channel. For example, the weight of the skin contact surface temperature is the highest, the temperature of the graphene film is the second, and the ambient temperature is mainly used for correction with the lowest weight. Then, the short-term jitter data is smoothed through the sliding time window mechanism to avoid interference from instantaneous fluctuations to the control judgment. Next, the abnormal detection logic is used to screen out short-term jump points, repeated points, or distorted samples, and interpolation is performed to complete the local missing points. Finally, a continuous, smooth, and credible temperature feedback data stream, that is, the fusion temperature monitoring data, is formed. The fused temperature data is input into the control strategy module of the system and compared point by point with the target temperature in the staged heating temperature output strategy to calculate the temperature deviation at the current moment, and based on this, the PID closed-loop adjustment mechanism is driven. PID control is a dynamic response system constructed based on the adjustment models in three directions: proportional, integral, and differential. It can perform feedback operations on the error between the target and the current state in three dimensions: immediate, historical, and trend. The proportional deviation reflects the real-time difference between the current temperature and the target temperature and is the most direct control basis. The integral deviation calculates the cumulative amount of the temperature difference within a certain time range and is used to correct the static error caused by long-term small deviations, improving the long-term stability of temperature control. The differential deviation focuses on the trend of the temperature change rate and can respond in advance when the temperature rises too fast or drops too quickly to prevent overshoot or oscillation of the control system. These three deviation amounts are weighted and calculated through the set PID parameter group to form the temperature deviation control parameter, which is used as the basic quantization instruction for the system to adjust the PWM signal. After the control system obtains the control parameters output by PID, it directly uses them to adjust the PWM control signal of the graphene electrothermal film, including the duty cycle size, the step size of the duty cycle change, the adjustment period, and the adjustment response curve.If the current temperature is lower than the target temperature, the system increases the PWM duty cycle according to the proportional deviation value to increase the heat output; if the temperature overshoot approaches the critical upper limit, the duty cycle is decreased according to the differential deviation trend to slow down the heating rhythm; if the temperature is consistently low but changes slowly, the system increases the average power output through integral deviation to restore the temperature control curve; when the three deviations balance each other, the system enters a dynamic equilibrium state, at which time the change amplitude of the output PWM signal tends to be small and fluctuates between 20% and 40% to maintain the stable operation of the constant temperature state. The entire adjustment period is 0.5 seconds to 1 second, ensuring that the adjustment is neither overly frequent nor lacks sufficient response speed. The finally output PWM signal is the stable temperature control signal.

[0045] In a specific embodiment, the process of executing step 500 may specifically include the following steps: Based on the stable temperature control signal, judge the end timing of the temperature change trend and usage time in the target area to obtain end timing judgment data; According to the end timing judgment data, perform progressive PWM duty cycle decreasing control on the graphene heating film to obtain a PWM decreasing control sequence; Based on the PWM decreasing control sequence, perform multiple safety protection state detections to obtain safety state monitoring data including over-temperature protection, abnormal contact protection, and time limit protection; According to the safety state monitoring data and the condition that the temperature in the target area returns to the ambient temperature range, confirm the stop state to obtain the safe stop state of the beauty device.

[0046] Specifically, based on the temperature platform state maintained by the stable temperature control signal, continuously monitor the temperature change trend of the skin surface in the target area and the cumulative time of the current use process. These two dimensions together constitute the core reference parameters for judging the end timing. Among them, the temperature change trend refers to the slope characteristic of the fused temperature data within a specific time window. If it is detected that the skin contact surface temperature has remained within the fluctuation range of ±0.5°C for 5 consecutive minutes and there is no sign of continuous increase or abnormal decrease, it is regarded that the temperature platform has reached a stable state. At the same time, the system calculates the total usage duration from the start of heating to the current time. If the cumulative usage time has reached the optimal skin care heat load range between 15 minutes and 20 minutes and no alarm event has been triggered, it is determined that the current nursing process is approaching the completion boundary. Therefore, the system will generate end timing judgment data based on the intersection of these two conditions, indicating that the current heating stage will gradually exit and enter the heat slow-down process. After generating the end judgment data, the system immediately makes a progressive decrease adjustment to the PWM control signal of the graphene electrothermal film and officially starts the cooling control mode. At this time, starting from the current duty cycle value, combined with the set cooling rate and cooling time window, a set of duty cycle decreasing sequences are gradually generated. This sequence is continuously adjusted at a rate of decreasing 5% every 30 seconds or in an equal amplitude reduction manner until the duty cycle drops to the minimum maintenance range of 10% to 15%. If the ambient temperature where the user is located is relatively high or the skin's sensitivity to heat is relatively low, the system will extend the decreasing time and control the PWM signal decline curve in a linear or exponential form with a cooling target of 1°C / minute to prevent thermal difference discomfort or skin stress reactions caused by sudden power reduction. During this decreasing process, the control module still maintains real-time sampling of the current, voltage, and film surface resistance to ensure that each change in the PWM signal generates a corresponding heat output feedback, thus forming a continuous, smooth, and gentle cooling process. At the same time, multiple safety protection mechanisms are activated during the cooling stage. By comprehensively monitoring the key safety dimensions in the working state, a composite safety state monitoring model covering temperature limits, electrical abnormalities, and time overrun is constructed. First is the overheat protection, continuously monitoring all skin contact surface sensing points and graphene film body temperature points. If any monitoring point still shows an abnormal temperature higher than 50°C during the cooling process, all PWM signals will be immediately interrupted, the event will be recorded, and the system will be forced to enter the protection mode. Second is the contact abnormality protection. Through multi-point capacitance induction electrodes, continuously judge whether the user's skin still maintains effective contact with the beauty instrument head during the heating process. If it is detected that the contact area drops sharply, the pressure disappears, or the capacitance fluctuates abnormally, the system will determine that the user has loosened or displaced, and immediately cut off the power output and lock the feedback channel. Finally is the time overrun protection. If the cumulative running time of the system since startup has exceeded the set upper limit (such as 20 minutes), regardless of whether it is currently on the temperature control platform or not, the heating process will be forced to terminate to prevent long-term heat load from causing micro-burning damage or epidermal dehydration to the skin.The above three types of protection logics are integrated by the system into an independent safety status monitoring module, which continuously performs status judgment and outputs monitoring results to form complete safety status monitoring data. In the later stage of the coordinated operation of PWM decreasing control and safety status monitoring, the actual cooling effect on the skin is determined according to the environmental temperature difference, and finally a decision is made on whether the shutdown operation can be executed. The temperature data of the skin contact surface is fused and compared with the environmental temperature baseline. If the average skin temperature continuously detected for more than 3 minutes is within 2°C below the upper limit of the environmental temperature, and the temperature change curve tends to be flat or even starts to return downward, it is determined that the cooling process is basically completed. At the same time, the system requires the above conditions to be synchronously verified with the safety status monitoring data to ensure that no temperature control overrun, contact interruption or other equipment abnormalities occur during the cooling period. If all judgment conditions are in the normal state, a final stop status confirmation signal is generated and a shutdown instruction is output to the main control unit.

[0047] In a specific embodiment, the process of performing step of progressive PWM duty cycle decreasing control on the graphene electrothermal film according to the determined end timing data may specifically include the following steps: Based on the temperature stability evaluation index in the determined end timing data, the initial PWM duty cycle is determined to obtain the initial PWM duty cycle value for progressive cooling and the target cooling rate parameter; According to the initial PWM duty cycle value and the target cooling rate parameter, the decreasing interval time and decreasing amplitude are calculated to obtain a PWM decreasing control strategy including a time interval and a decreasing percentage; Based on the PWM decreasing control strategy, a duty cycle decreasing time sequence is generated to obtain PWM time sequence decreasing data with the duty cycle value gradually decreasing at a preset time interval; According to the PWM time sequence decreasing data, the total duration and termination conditions of the cooling process are set to obtain a PWM decreasing control sequence.

[0048] Specifically, the initial PWM duty cycle is determined based on the temperature stability evaluation index in the end timing judgment data. This temperature stability evaluation index includes the maximum fluctuation value, average fluctuation slope of the skin contact area temperature change within multiple consecutive time windows, and the change offset within a five-minute section. Through the mathematical processing of these differential change data, it is judged whether the current temperature control platform has reached a stable period, whether there is a potential temperature increase trend, or whether it is about to enter the natural temperature recovery range. If the temperature stability performs well, with the fluctuation range within ±0.5°C, the temperature slope approaching zero or slowly decreasing, the cooling logic is triggered. On this basis, the last set of PWM duty cycle data used to maintain the constant temperature state is used as the initial cooling point. At the same time, the system retrieves the user's skin type, contact surface heat response category, and care mode label from the personalized temperature control database, and combines the preset human comfort cooling rate standard (such as a temperature drop of 1°C per minute) to comprehensively generate the target cooling rate parameter, thereby determining the rate boundary and initial power state of the cooling behavior. According to the above initial PWM duty cycle value and target cooling rate parameter, enter the decreasing strategy calculation module to deduce the optimal decreasing interval time and single-step decreasing amplitude. This calculation process needs to comprehensively consider three main factors: the first is the heat capacity and conduction delay of the graphene material, that is, the actual heat attenuation lag caused by the reduction of electric power per unit time; the second is the skin perception heat buffer response model to prevent discomfort reactions caused by the user suddenly feeling "heat loss" during the cooling process; the third is the matching degree between the device heat dissipation mechanism and the environmental heat exchange rate. Therefore, the initial duty cycle reduction is divided into multiple discrete time windows for step-by-step attenuation, with a time interval of 30 seconds and a decreasing amplitude set at 5% or dynamically adjusted to a floating range between 3% and 7% according to the rate target, constructing a decreasing control strategy including the structure of "decreasing y% every x seconds", forming a combined adjustment map of the time domain and duty cycle amplitude domain. Generate the operation of the clear execution timing in the decreasing control strategy, and construct the complete PWM decreasing timing data according to the aforementioned time interval and amplitude configuration. This data consists of multiple groups of PWM signals, and each group of data records the target duty cycle value after each decrease and the time period it continues to maintain. Based on this, the system drives the PWM output module to execute precise duty cycle regulation. Taking the initial duty cycle of 40%, decreasing amplitude of 5%, and interval of 30 seconds as an example, the system sequentially generates PWM values at multiple stages such as 35%, 30%, 25%, 20%, 15%, etc., and transmits them to the control channel through the timing scheduling mechanism, thereby gradually attenuating the input power of the graphene electrothermal film at the physical layer, slowing down the heat release rhythm, and the skin-perceived temperature will also drop in a slow, stable, and linearly approaching the natural temperature manner, thus avoiding skin irritation, sudden vasoconstriction, or capillary congestion caused by sudden power drop or forced heat cut-off, ensuring the mildness and physiological safety of the fever reduction process.During the stable execution of the cooling behavior, the total duration and stop conditions of the entire cooling process are dynamically set, and a boundary condition system for the entire cooling process is constructed in combination with the PWM timing decreasing data. The initial setting of the total duration is obtained by inversely deducing based on the power minimum maintenance time requirement and the target temperature drop rate, and is controlled within the range of 3 minutes to 5 minutes, which can not only ensure that the temperature drops, but also prevent redundant occupation of device resources due to too slow cooling. At the same time, a temperature termination condition is set, that is, if it is detected at any time that the skin contact surface temperature has dropped within the range of the ambient temperature ±2°C and remains in this state for more than 1 minute, it is considered that the cooling is completed; if this condition and the state that the decreasing sequence has been executed are satisfied at the same time, the system determines that the current cooling process has ended, and outputs the final PWM decreasing control sequence completion signal. At this time, the system automatically cuts off the power supply signal of the electrothermal film, closes all heating-related modules, and records key information such as the duty cycle evolution curve, time length, thermal response characteristics, and user skin temperature recovery trend of this cooling section, providing available data for the initialization of temperature control parameters and the self-learning of the user model in the next use.

[0049] The control method of the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect in the embodiment of the present invention has been described above. Next, the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect in the embodiment of the present invention will be described. Please refer to Figure 2 , an embodiment of the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect in the embodiment of the present invention includes: A pre-activation module 11 for pre-activating the graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters; A contact state detection module 12 for detecting the contact state of the target area and performing multi-parameter analysis to obtain personalized temperature control parameters; A power control module 13 for performing PWM segmented power control on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters to obtain a phased heating temperature output strategy; A real-time feedback adjustment module 14 for performing real-time feedback adjustment based on the phased heating temperature output strategy to obtain a stable temperature control signal; A cooling power adjustment module 15 for performing progressive cooling power adjustment on the graphene electrothermal film according to the stable temperature control signal and confirming the safe stop state of the beauty instrument.

[0050] Through the collaborative cooperation of the above-mentioned various components, the present invention realizes an accurate control method of inversely calculating the temperature by real-time monitoring of the resistance value change by establishing the negative temperature coefficient resistance characteristic parameters of the graphene electrothermal film and utilizing the unique characteristic that the resistance value of the graphene material decreases when the temperature rises. Compared with traditional linear resistance materials, it has higher temperature control accuracy and response speed. By adopting a multi-point distributed capacitive sensing electrode array, multi-dimensional information such as contact area, pressure distribution, and contact angle can be detected simultaneously. Compared with the existing single-point contact detection technology, it significantly improves the accuracy and comprehensiveness of contact state recognition, providing a reliable data basis for subsequent personalized control. By performing multi-parameter analysis on the target area and establishing a personalized temperature control database based on contact characteristics, the temperature parameters can be automatically adjusted according to different skin types and characteristics, realizing a technological leap from the traditional fixed temperature mode to the intelligent personalized control mode. By using pulse width modulation technology to perform segmented power control on the graphene electrothermal film, through the refined management of the preheating stage, stable heating stage, and heat preservation stage, the advantages of rapid heating and precise temperature control of the graphene material are fully exerted. Compared with the traditional linear voltage regulation method, it has higher energy efficiency and control accuracy. By establishing a multi-level temperature monitoring system and adopting multi-sensor data fusion and PID control algorithms, real-time monitoring and dynamic adjustment of the temperature control process are realized, effectively avoiding the temperature fluctuation problem in the traditional on-off control mode and ensuring the temperature stability during the nursing process. Through the intelligent end timing judgment and PWM duty cycle decreasing control, a smooth transition from the nursing temperature to the ambient temperature is realized, avoiding the discomfort caused by the sudden stop of heating of traditional equipment. At the same time, by integrating multiple safety protection mechanisms, the safety and comfort during use are significantly improved.

[0051] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0052] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing an electronic device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs.

[0053] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A control method for a deep skin anti-wrinkle beauty device applying the graphene electrothermal effect, characterized in that, Including: Pre-activate the graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters; Detect the contact state and perform multi-parameter analysis on the target area to obtain personalized temperature control parameters; Based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters, perform PWM segmented power control on the graphene electrothermal film to obtain a staged heating temperature output strategy; Based on the staged heating temperature output strategy, perform real-time feedback adjustment to obtain a stable temperature control signal; According to the stable temperature control signal, perform progressive cooling power adjustment on the graphene electrothermal film, and at the same time confirm the safe stop state of the beauty instrument.

2. The control method of the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 1, characterized in that, The pre-activating the graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters includes: Apply an excitation voltage pulse signal within a preset voltage range to the graphene electrothermal film and collect stable conductance state data; Perform real-time resistance value change monitoring on the stable conductance state data to obtain a dynamic resistance value sequence of the graphene electrothermal film during pre-activation; Based on the dynamic resistance value sequence and the corresponding temperature data, perform resistance-temperature characteristic curve modeling to obtain a negative temperature coefficient resistance model; Based on the negative temperature coefficient resistance model, perform parameter extraction to obtain negative temperature coefficient resistance characteristic parameters including a reference resistance value, a temperature coefficient, and a response time constant.

3. The control method of the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 1, characterized in that, The detecting the contact state and performing multi-parameter analysis on the target area to obtain personalized temperature control parameters includes: Based on the capacitance value changes of each induction electrode in the multi-point capacitive induction electrode array, perform real-time monitoring on the target area to obtain capacitance change data of each induction electrode; Based on the capacitance change data of each induction electrode and a preset capacitance threshold, perform effective contact determination to obtain effective contact electrode distribution information; Based on the capacitance value differences between different induction electrodes in the effective contact electrode distribution information, perform contact parameter calculation to obtain contact area distribution data and contact pressure distribution data; Based on the contact area distribution data and the contact pressure distribution data, perform multi-parameter analysis on the target area to obtain personalized temperature control parameters.

4. The control method of a deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 3, characterized in that, The performing multi-parameter analysis on the target area based on the contact area distribution data and the contact pressure distribution data to obtain personalized temperature control parameters includes: Based on the contact area distribution data and the contact pressure distribution data, perform regional characteristic detection on the target area to obtain multi-dimensional regional characteristic data; Based on the multi-dimensional regional characteristic data, perform type classification to obtain a regional type recognition result; Based on the regional type recognition result, query the personalized temperature control database to obtain basic temperature control parameters; Based on the basic temperature control parameters and the contact area distribution data, perform temperature correction to obtain personalized temperature control parameters.

5. The control method of a deep skin anti-wrinkle beauty device applying the graphene electrothermal effect according to claim 1, characterized in that, The performing PWM segmented power control on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters to obtain a staged heating temperature output strategy includes: Calculate the PWM basic control parameters according to the personalized temperature control parameters and the negative temperature coefficient resistor characteristic parameters, where the PWM basic control parameters include the control frequency and the duty cycle adjustment range; Based on the PWM basic control parameters, set the duty cycle in segments for the preheating stage, the stable heating stage, and the heat preservation stage to obtain the PWM duty cycle control sequence corresponding to each heating stage; Establish the non-linear response relationship between the power of the graphene electrothermal film and the temperature according to the negative temperature coefficient resistor characteristic parameters to obtain the power-temperature response relationship data; Based on the PWM duty cycle control sequence and the power-temperature response relationship data, analyze the temperature output strategy in stages for the graphene electrothermal film to obtain the temperature output strategy for staged heating.

6. The control method of a deep skin anti-wrinkle beauty device applying the graphene electrothermal effect according to claim 5, characterized in that, The establishment of the non-linear response relationship between the power of the graphene electrothermal film and the temperature according to the negative temperature coefficient resistor characteristic parameters to obtain the power-temperature response relationship data includes: Based on the reference resistance value and the temperature coefficient in the negative temperature coefficient resistor characteristic parameters, analyze the resistance change law of the graphene electrothermal film in different temperature intervals to obtain the resistance change curve data for the temperature intervals; Conduct an analysis of the reverse mapping relationship between resistance and temperature based on the resistance change curve data for the temperature intervals to obtain a temperature calculation model for calculating the temperature by reverse deduction from the resistance value; Based on the temperature calculation model, conduct real-time power calculation to obtain a sequence of power output values corresponding to different temperature intervals; Conduct non-linear fitting based on the sequence of power output values to obtain the power-temperature response relationship data of the non-linear response relationship between the power of the graphene electrothermal film and the temperature.

7. The control method of the deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 1, characterized in that, The real-time feedback adjustment based on the temperature output strategy for staged heating to obtain a stable temperature control signal includes: Synchronously collect the self-temperature, the contact surface temperature of the target area, and the ambient temperature of the graphene electrothermal film based on a multi-level temperature monitoring system to obtain multi-channel temperature feedback data; Conduct multi-sensor data fusion based on the multi-channel temperature feedback data to obtain fused temperature monitoring data; Based on the fused temperature monitoring data and the target temperature in the temperature output strategy for staged heating, conduct PID control to obtain temperature deviation control parameters including proportional deviation, integral deviation, and differential deviation; Dynamically adjust the PWM control parameters of the graphene electrothermal film according to the temperature deviation control parameters to obtain a stable temperature control signal.

8. The control method of a deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 1, characterized in that, The progressive cooling power adjustment of the graphene electrothermal film according to the stable temperature control signal and simultaneously confirm the safe stop state of the beauty device includes: Based on the stable temperature control signal, judge the end timing of the temperature change trend and the usage time of the target area to obtain end timing judgment data; Conduct a progressive PWM duty cycle decreasing control on the graphene electrothermal film according to the end timing judgment data to obtain a PWM decreasing control sequence; Based on the PWM decreasing control sequence, conduct a multi-level safety protection state detection to obtain safety state monitoring data including over-temperature protection, abnormal contact protection, and time limit protection; Based on the safety status monitoring data and the condition that the temperature of the target area returns to the ambient temperature range, the safety stop state of the beauty device is confirmed.

9. The control method of a deep skin anti-wrinkle beauty instrument applying the graphene electrothermal effect according to claim 8, characterized in that, The progressive PWM duty ratio decreasing control of the graphene electrothermal film according to the end timing judgment data to obtain a PWM decreasing control sequence includes: Based on the temperature stability evaluation index in the end timing judgment data, the initial PWM duty ratio is determined to obtain the initial PWM duty ratio value for progressive temperature reduction and the target temperature reduction rate parameter; According to the initial PWM duty ratio value and the target temperature reduction rate parameter, the decreasing interval time and the decreasing amplitude are calculated to obtain a PWM decreasing control strategy including a time interval and a decreasing percentage; Based on the PWM decreasing control strategy, the duty ratio decreasing time sequence is generated to obtain PWM time sequence decreasing data with the duty ratio value gradually decreasing at a preset time interval; According to the PWM time sequence decreasing data, the total duration of the temperature reduction process and the termination condition are set to obtain a PWM decreasing control sequence.

10. A deep skin anti-wrinkle beauty device applying the electrothermal effect of graphene, characterized in that, For implementing the control method of a deep skin anti-wrinkle beauty device applying graphene electrothermal effect as described in any one of claims 1-9, it includes: A pre-activation module for pre-activating the graphene electrothermal film to obtain negative temperature coefficient resistance characteristic parameters; A contact state detection module for detecting the contact state of the target area and performing multi-parameter analysis to obtain personalized temperature control parameters; A power control module for performing PWM segmented power control on the graphene electrothermal film based on the personalized temperature control parameters and the negative temperature coefficient resistance characteristic parameters to obtain a staged heating temperature output strategy; A real-time feedback adjustment module for performing real-time feedback adjustment based on the staged heating temperature output strategy to obtain a stable temperature control signal; A temperature reduction power adjustment module for performing progressive temperature reduction power adjustment on the graphene electrothermal film according to the stable temperature control signal and simultaneously confirming the safety stop state of the beauty device.

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