System for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors

Abstract

A system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors, wherein the system comprises the following: a flexible substrate configured to conform to the surface of human skin; a multitude of sensor elements arranged within or above the flexible substrate and configured to detect physiological signals such as electrical cardiac activity, respiratory movement, and blood perfusion characteristics; a conductive interconnect structure embedded in the flexible substrate that electrically couples the multitude of sensor elements; a signal acquisition unit that is operationally connected to the multitude of sensor elements and is configured to amplify, filter, and digitize the acquired physiological signals; a processing unit that is operationally coupled with the signal acquisition unit and is configured for signal processing, feature extraction and estimation of physiological parameters; a wireless communication unit that is operationally connected to the processing unit and configured to transmit processed physiological data to an external device; and A power supply unit integrated into and configured within the flexible substrate provides the system with electrical energy. The flexible substrate and sensor elements are arranged to maintain adaptable and continuous contact with the skin, reducing motion-related artifacts and improving signal quality during continuous monitoring.

Description

Technical field of the invention

[0001] The present invention relates to the field of biomedical engineering, wearable health monitoring systems, and bioelectronic sensor technologies. In particular, the invention relates to a system and an associated device structure for the continuous, non-invasive monitoring of cardiorespiratory parameters using flexible, adaptable bioelectronic skin sensors that can acquire, process, and transmit physiological data in real time. Background of the invention

[0002] Continuous monitoring of cardiorespiratory functions, including heart rate, respiratory rate, blood oxygen saturation, and chest movements, is crucial for the early detection and treatment of chronic and acute conditions. Conventional monitoring systems, such as ECG devices and pulse oximeters, are typically rigid, bulky, and limited to clinical settings, restricting patient mobility and long-term use. Wearable devices on the market often exhibit limited accuracy due to motion artifacts, insufficient skin contact, and a lack of multimodal sensor capabilities. Furthermore, such systems are not optimized for continuous use due to discomfort and signal degradation. Therefore, there is a need for a flexible, skin-friendly, and highly sensitive bioelectronic system capable of reliably monitoring cardiorespiratory signals in real time with minimal interference and high wearing comfort.

[0003] Continuous cardiorespiratory monitoring has evolved significantly in recent decades – from bulky, stationary devices to compact, portable technologies for outpatient and home care. Traditional clinical systems such as electrocardiography (ECG), spirometry, and capnography were long considered the gold standard for monitoring cardiac and respiratory parameters due to their high accuracy and reliability. However, these systems are inherently limited by their size, rigid design, and reliance on wired connections and stationary installations, making them unsuitable for long-term, continuous monitoring outside of clinical settings. Patients typically need to remain in controlled environments, which restricts their natural movement and makes it difficult to detect physiological changes in daily life.Therefore, these conventional systems do not provide a comprehensive picture of physiological behavior in everyday life, which is crucial for the early detection of temporary or activity-related anomalies.

[0004] To overcome these limitations, wearable monitoring devices have been introduced, including chest straps, wrist-worn fitness trackers, smartwatches, and patch systems. Chest straps, commonly used in sports and clinical telemetry, utilize ECG electrodes or impedance measurement to detect heart rate and respiration. While these systems offer improved wearability compared to traditional devices, they remain relatively uncomfortable due to the tight strap and potential skin irritation with prolonged wear. Furthermore, their rigid structure limits adaptability to different body types and can lead to uneven electrode contact, resulting in degraded signal quality over time. Additionally, such systems are typically designed for short-term monitoring and are not optimized for continuous use over several days or weeks.

[0005] Wrist-worn wearables, primarily based on photoplethysmography (PPG) sensors, are popular due to their comfort and user-friendly design. These devices estimate heart rate and, in some cases, indirectly derive respiratory rate from pulse wave variations. However, numerous studies have shown that the accuracy of such devices is highly dependent on the user's activity level. While they provide acceptable accuracy at rest, their performance deteriorates significantly at moderate to high intensity due to motion-induced artifacts and sensor shifts. The use of optical sensors presents additional challenges, as PPG signals are highly susceptible to changes in skin tone, interference from ambient light, and the dynamics of blood perfusion.Repetitive movements such as walking or arm swinging can cause signal interference and thus lead to inaccurate heart rate measurements. These inaccuracies limit the clinical reliability of wrist-worn devices, especially in situations requiring precise real-time monitoring.

[0006] Another crucial limitation of existing wearable systems is motion artifacts, which remain one of the biggest challenges in ambulatory physiological monitoring. These artifacts arise from the relative movement between the sensor and the skin, mechanical deformation of the sensor surface, and changes in contact pressure. They can distort both ECG and PPG signals, leading to missing or inaccurate readings and reduced signal quality. In practice, motion artifacts are unavoidable, as users engage in routine physical activities throughout the day. Even advanced filtering techniques often cannot completely eliminate these artifacts, especially when the noise characteristics are non-stationary and unpredictable. Consequently, the reliability of continuous monitoring systems is compromised, particularly in dynamic environments.

[0007] Respiratory monitoring using wearable devices introduces additional complexities. Conventional methods such as spirometry and capnography, while highly accurate, are unsuitable for continuous use due to their invasive nature. Wearable alternatives, including chest straps and strain gauges, attempt to measure thoracic expansion or infer respiration from substitute signals such as ECG or accelerometer measurements. However, these approaches are frequently affected by movement, changes in posture, and variations in breathing patterns. For example, wearable respiratory monitoring systems may provide inaccurate readings if the subject is moving, as the techniques may not be able to distinguish between respiratory signals and movement-related disturbances. Furthermore, errors in estimating respiratory rate tend to increase significantly after physical exertion, highlighting the limitations of current measurement mechanisms under dynamic conditions.In some cases, motion-related artifacts can even trigger false alarms and limit the clinical applicability of such systems.

[0008] Another drawback of existing solutions is the lack of robust multimodal sensing and data fusion capabilities. Many commercial devices rely on a single sensor modality, such as PPG or accelerometer, which limits their ability to accurately capture complex physiological interactions. Although recent research has explored multimodal approaches using ECG, PPG, and motion sensors, the reliable and energy-efficient integration of these signals remains a significant challenge. The processing demands of such systems often exceed the capabilities of low-power portable hardware, leading to compromises in sampling rates, signal resolution, or technical complexity. This compromise can impair the detection of subtle physiological changes, such as the onset of cardiac arrhythmias or irregular breathing.

[0009] Energy consumption and battery life further limit the performance of existing portable monitoring systems. Continuous data acquisition, signal processing, and wireless transmission require significant energy, especially in multi-sensor configurations. To conserve energy, many devices use reduced sampling rates or intermittent monitoring strategies, which can lead to information loss and lower temporal resolution. Furthermore, frequent charging requirements decrease user acceptance and limit the practicality of long-term monitoring applications.

[0010] Comfort and acceptance represent another significant limitation of current technologies. Wearables must maintain constant skin contact to enable accurate measurements. However, prolonged wear can lead to discomfort, skin irritation, and reduced adhesion. Studies have shown that even clinically accurate wearables often suffer from low acceptance due to poor usability and ergonomic design. Rigid or semi-flexible devices may not conform to natural body contours, resulting in gaps in the sensor-skin contact area and, consequently, signal degradation. While adhesive patches are more adaptable, they can lose adhesion over time due to sweat, movement, or environmental factors.

[0011] Furthermore, many existing systems are limited in their ability to continuously monitor cardiac and respiratory parameters simultaneously and with high resolution. While some devices deliver excellent results in cardiac monitoring and others in respiratory monitoring, few systems offer integrated, high-precision measurement of both domains on a single platform. This limitation complicates the comprehensive assessment of cardiorespiratory coupling, which is essential for understanding conditions such as sleep apnea, chronic obstructive pulmonary disease, and heart failure.

[0012] Finally, data reliability and clinical validation remain challenges for wearable monitoring technologies. While many devices demonstrate acceptable performance under controlled laboratory conditions, their accuracy often decreases in everyday use, which is characterized by varying user behavior and environmental influences. The variability in device performance depending on the user, activity, and wearing conditions underscores the need for more robust and adaptive sensor systems.

[0013] In light of the preceding discussion, it is clear that existing cardiorespiratory monitoring solutions, including traditional clinical systems and modern wearables, have significant limitations. These include motion artifacts, limited accuracy under dynamic conditions, an inadequate sensor-skin interface, insufficient multimodal integration, energy limitations, and a lack of user acceptance. These drawbacks underscore the need for advanced systems with flexible, adaptable bioelectronic skin sensors that ensure stable contact, minimize artifacts, and enable precise, continuous monitoring in everyday life. Summary of the invention

[0014] The present invention describes a system and device for continuous cardiorespiratory monitoring using a flexible bioelectronic skin sensor structure that seamlessly adapts to the human epidermis. The system comprises a multilayered, flexible substrate with multiple sensor elements for acquiring electrophysiological, mechanical, and biochemical signals. The sensor elements are coupled to a signal acquisition unit, which in turn is connected to a processing unit. This unit performs signal conditioning, feature extraction, and anomaly detection in real time. The system also includes a wireless transmission unit for transmitting the processed data to an external device or a cloud infrastructure. The device structure is designed to ensure optimal contact with the skin surface, thereby reducing motion artifacts and improving signal quality.

[0015] The present invention aims to provide a system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors. This system is designed to acquire highly precise physiological signals non-invasively while ensuring optimal skin contact. The invention overcomes the limitations of rigid and bulky conventional monitoring systems through a mechanically flexible device structure that adapts to the natural contours and movements of the body, thus ensuring consistent signal acquisition over extended periods of wear.

[0016] A further objective of the invention is the simultaneous and continuous monitoring of multiple cardiorespiratory parameters, including electrical cardiac activity, respiratory patterns, pulse dynamics, and associated physiological indicators, on a single integrated platform. The invention aims to provide a unified sensor architecture that enables multimodal data acquisition and synchronization, thereby improving the accuracy and reliability of physiological measurements and allowing for a comprehensive analysis of cardiorespiratory interactions.

[0017] Another objective of the invention is to minimize motion-induced artifacts and signal degradation, which frequently occur with wearable monitoring devices. Through the use of flexible materials, stretchable connections, and optimized sensor placement, the system ensures stable skin contact during various physical activities, thus improving signal quality even under dynamic conditions. This enables reliable monitoring in everyday life, for example, during daily activities, sports, and sleep.

[0018] A further objective of the invention is to provide an efficient signal acquisition and processing mechanism that enables real-time data preparation, feature extraction, and anomaly detection. The invention is designed to integrate advanced processing techniques that allow for the precise identification of physiological events such as arrhythmias, irregular breathing patterns, and oxygen desaturation, thereby supporting early diagnosis and timely medical intervention.

[0019] A further objective of the invention is energy-saving operation, suitable for continuous long-term monitoring without frequent user intervention. The system integrates energy-efficient components and optimized energy management strategies to extend operating time, improve user acceptance, and enable uninterrupted physiological monitoring.

[0020] A further objective of the invention is to ensure wearing comfort and biocompatibility through the use of soft, lightweight, and breathable materials that can be worn continuously without causing irritation or discomfort. The device design is intended to be as inconspicuous as possible, thereby promoting longer wearing times and higher patient adherence in both clinical and non-clinical settings.

[0021] Another objective of the invention is to provide a reliable wireless communication mechanism for transmitting processed physiological data to external devices or telemedicine systems. The invention enables real-time data exchange, remote monitoring, and integration into telemedicine platforms, thereby supporting decentralized healthcare and reducing the frequency of hospital visits.

[0022] A further objective of the invention is to improve data security and integrity during transmission and storage through the integration of secure communication protocols and processing security mechanisms. This ensures that sensitive physiological data is protected from unauthorized access while maintaining accessibility for authorized medical personnel.

[0023] A further objective of the invention is to provide a scalable and adaptable device structure that can be configured for different user groups and medical applications. The system is designed to take into account variations in body morphology, physiological conditions, and monitoring requirements, thereby extending its applicability to diverse areas of healthcare.

[0024] Overall, the invention aims to provide a comprehensive, reliable and user-friendly solution for continuous cardiorespiratory monitoring that overcomes the shortcomings of existing technologies while enabling accurate physiological assessment in real time and over extended periods in both clinical and everyday settings. BRIEF DESCRIPTION OF THE IMAGE

[0025] These and other features, aspects and advantages of the present invention will be better understood if the following detailed description is read with reference to the accompanying drawing, in which the same symbols represent the same parts: Fig. Figure 1 shows a block diagram of a system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors.

[0026] Furthermore, those skilled in the art will recognize that the elements in the drawing are simplified and not necessarily drawn to scale. For example, the flowcharts illustrate the process by highlighting the main steps to facilitate understanding of the present disclosure. With regard to the construction of the device, one or more components may be represented in the drawing by conventional symbols. The drawing may show only those specific details relevant to understanding the embodiments of the present disclosure, so as not to clutter the drawing with details that are already apparent to those skilled in the art from the description contained herein. Detailed description of the invention

[0027] To facilitate understanding of the principles of the invention, reference is made below to the embodiment shown in the drawing, which is described using specific terms. It is understood, however, that this does not limit the scope of protection of the invention. Rather, modifications and further developments of the depicted system, as well as further applications of the inventive principles shown therein, are conceivable, insofar as they would normally occur to a person skilled in the art in the field of the invention.

[0028] It will be clear to those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not to be understood as a limitation thereof.

[0029] References to “an aspect”, “another aspect”, or similar phrases in this description mean that a particular feature, structure, or property described in connection with the embodiment is included in at least one embodiment of the present disclosure. Therefore, phrases such as “in one embodiment”, “in another embodiment”, and similar expressions in this description may, but do not necessarily, all refer to the same embodiment.

[0030] The terms "includes," "comprehensive," or similar expressions denote non-exclusive inclusion. Thus, a procedure or method containing a list of steps does not only include those steps but may also include further steps not explicitly listed or inherent in the procedure or method. Likewise, the statement "includes..." for one or more devices, subsystems, elements, structures, or components, without further limitations, does not preclude the existence of other devices, subsystems, elements, structures, or components.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meanings generally known to those skilled in the art in the field to which this invention belongs. The systems, methods, and examples described herein serve only for illustration and are not to be understood as limiting.

[0032] Embodiments of the present disclosure are described in detail below with reference to the attached drawing.

[0033] Fig.Figure 1 shows a block diagram of a system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors. The system 100 comprises: a flexible substrate (102) that conforms to the surface of human skin; a plurality of sensor elements (104) arranged within or above the flexible substrate and configured to detect physiological signals such as electrical cardiac activity, respiratory motion, and blood perfusion characteristics; a conductive interconnect structure (106) embedded in the flexible substrate that electrically couples the plurality of sensor elements; and a signal acquisition unit (108) that is operationally connected to the plurality of sensor elements and configured to amplify, filter, and digitize the detected physiological signals.a processing unit (110) operationally coupled to the signal acquisition unit and configured to perform signal conditioning, feature extraction, and estimation of physiological parameters; a wireless communication unit (112) operationally connected to the processing unit and configured to transmit processed physiological data to an external device; and a power unit (114) integrated into the flexible substrate and configured to supply electrical power to the system, wherein the flexible substrate and the sensor elements are arranged to maintain compliant and continuous contact with the skin to reduce motion-induced artifacts and improve signal accuracy during continuous monitoring.

[0034] In one embodiment, the flexible substrate (102) comprises an elastomeric, biocompatible material selected to have mechanical properties similar to those of human skin, thereby enabling stretchability, flexibility and long-term wearability without delamination or discomfort, wherein the substrate further comprises a multilayer structure including a base layer, a conductive intermediate layer and an encapsulation layer.

[0035] In one embodiment, the plurality of sensor elements (104) comprises a set of electrodes configured to detect electrical cardiac activity. The electrodes are made of conductive materials and coated with a hydrogel interface layer to reduce skin-electrode impedance and improve signal stability over extended periods.

[0036] In one embodiment, the plurality of sensor elements (!04) further comprises at least one strain-sensitive element configured to detect the mechanical deformation of the thoracic region associated with respiratory cycles. The strain-sensitive element comprises a piezoresistive or capacitive structure arranged in a deformable pattern to detect multidirectional expansion and contraction.

[0037] In one embodiment, the plurality of sensor elements (104) further comprises an optical sensor arrangement with at least one luminescent element and at least one photodetector configured to measure changes in blood volume, thus enabling the estimation of pulse characteristics and oxygen saturation levels.

[0038] In one embodiment, the conductive interconnect structure (106) comprises stretchable conductor tracks arranged in serpentine or fractal geometries to maintain electrical continuity under mechanical deformation, wherein the conductor tracks are made of materials such as metallic thin films, nanowire networks or carbon-based conductive materials.

[0039] In one embodiment, the signal acquisition unit (108) comprises a low-noise amplification circuit for amplifying weak physiological signals, an analog filter circuit for eliminating baseline deviations and high-frequency noise, and an analog-to-digital converter circuit for converting processed analog signals into digital signals with a predefined sampling rate.

[0040] In one embodiment, the processing unit (110) is configured to perform functions for recognizing characteristic features from the acquired signals, including the identification of cardiac cycle events, the segmentation of respiratory cycles, and the estimation of temporal relationships between cardiac and respiratory signals.

[0041] In one embodiment, the processing unit (110) is further configured to analyze the extracted features in order to identify abnormal physiological conditions such as irregular heart rhythms, abnormal breathing patterns and reduced blood oxygen levels based on predefined thresholds or trained computational models.

[0042] In one embodiment, the wireless communication unit (112) comprises an energy-saving transceiver configured for data transmission using short-range or long-range communication protocols, wherein the unit has a flexible antenna structure integrated into the flexible substrate to maintain transmission performance even when deformed.

[0043] The system is fully integrated into a portable, flexible platform and consists exclusively of physical and structural components. Each functional block is implemented using dedicated hardware elements rather than abstract processing concepts. The flexible substrate is made of a skin-compatible elastomer into which conductive traces, sensor elements, and encapsulation layers are embedded to ensure stable mechanical and electrical performance even under deformation. Heart rate measurement is achieved via electrode structures made of conductive materials with hydrogel interfaces, ensuring stable biopotential coupling. Respiratory monitoring is implemented using strain-sensitive hardware elements such as piezoresistive or capacitive deformation sensors that respond to chest movements. Blood perfusion is measured using integrated optical hardware with LEDs and photodetectors that detect light absorption in the tissue.Signal processing is performed by integrated electronics with low-noise amplifiers, passive and active filters, and an analog-to-digital converter that digitizes physiological signals. Subsequent physiological analysis is carried out by a dedicated processing circuit implemented as embedded electronic hardware, capable of performing predefined signal interpretation and feature recognition functions directly within the device. Wireless data transmission is achieved through a compact high-frequency transceiver circuit connected to a physically integrated antenna.

[0044] This is integrated into the flexible substrate to ensure communication performance even when bent and stretched.

[0045] The system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors operates with a coordinated sequence of signal acquisition, processing, feature extraction, data fusion, and physiological interpretation processes, which are executed by the processing unit in conjunction with the signal acquisition unit. The technology implemented in the processing unit is specifically designed for processing multimodal physiological input signals from electrical, mechanical, and optical sensor elements and simultaneously compensates for motion-related disturbances and fluctuations of the skin-electrode interface.After initialization, the signal acquisition unit continuously receives analog signals from the various sensor elements, including electrical potentials corresponding to cardiac activity, mechanical deformation signals corresponding to respiration, and optical signals reflecting blood perfusion characteristics. These analog signals are first amplified by a low-noise amplification circuit to ensure that weak physiological signals are boosted above the noise without distortion.

[0046] After amplification, the signals undergo analog filtering to remove unwanted frequency components. A high-pass filter eliminates baseline deviations caused by slow changes in skin impedance and movement, while a low-pass filter suppresses high-frequency noise originating from environmental disturbances and electronic components. The filtered analog signals are then digitized using an analog-to-digital converter at a sampling rate that ensures the temporal resolution required for precise physiological analysis. The digitized signals are then transferred to the processing unit, where the actual analysis procedures are performed.

[0047] The processing unit first performs digital signal conditioning, including normalization, baseline correction, and adaptive noise reduction. Normalization scales the signal amplitudes to a uniform range to facilitate subsequent analysis. Baseline correction compensates for remaining drift using methods such as moving average subtraction or polynomial fitting. Adaptive noise reduction is implemented through filtering techniques that dynamically adjust their parameters based on real-time signal characteristics. In one embodiment, a recursive filtering technique is used, in which the filter coefficients continuously respond to detected motion or signal irregularities. This effectively attenuates motion artifacts without compromising the integrity of the underlying physiological signals.

[0048] Following signal processing, feature extraction takes place. During the analysis of the heart signal, the processing unit identifies characteristic waveform components by detecting peaks corresponding to cardiac cycles. To this end, the first and second derivatives of the signal are calculated to detect rapid changes indicative of cardiac events. Subsequently, threshold-based or adaptive peak detection is performed to locate specific features. The time intervals between successive peaks are calculated to determine heart rate and heart rate variability. Additionally, a morphological analysis of the waveform is conducted to extract waveform, amplitude, and duration features that provide information about cardiac health and rhythm regularity.

[0049] To analyze the respiratory signal, the processing unit evaluates the mechanical deformation signals detected by the strain-sensitive elements. The method identifies periodic patterns corresponding to the inhalation and exhalation phases by detecting cyclical signal variations. Zero-crossing detection, peak-to-peak amplitude analysis, and frequency domain transformations are used to determine the respiratory rate and pattern. In certain implementations, spectral analysis is performed using discrete transformation techniques to isolate the dominant frequency components associated with respiration, thereby improving robustness against noise and interference.

[0050] The optical signals captured by the light and photodetector array are processed to extract pulse-related features. The processing unit calculates the changes in light intensity associated with changes in blood volume and applies filtering techniques to isolate the pulsatile component of the signal. From this processed signal, the pulse frequency is derived, and other parameters such as pulse amplitude and temporal characteristics are calculated. The method also evaluates relative changes in optical absorption at different wavelengths to determine the oxygen saturation level. Compensation mechanisms account for variations in skin properties, ambient light conditions, and sensor positioning.

[0051] A key aspect of the system is the synchronization and fusion of data acquired by the various sensor elements. The processing unit compares the time-series data of cardiac, respiratory, and optical signals using a common time reference, thus enabling the integrated analysis of cardiorespiratory interactions. Cross-correlation methods are used to determine temporal relationships between signals, such as the delay between cardiac events and peripheral pulse measurements. This integrated analysis allows for the estimation of composite parameters, including pulse waveforms and the coupling between the cardiac and respiratory cycles.

[0052] The system also includes anomaly detection mechanisms to identify deviations from normal physiological patterns. The processing unit compares extracted features with predefined thresholds or stored reference patterns. Furthermore, adaptive models can be used to capture individual baseline characteristics over time, thus enabling personalized monitoring. If abnormal patterns such as cardiac arrhythmias, abnormal breathing cycles, or reduced oxygen levels are detected, the processing unit generates alerts and marks the corresponding data for transmission.

[0053] To ensure reliable operation under dynamic conditions, the method includes strategies for detecting and compensating for motion artifacts. Motion-related disturbances are identified by analyzing signal inconsistencies, abrupt amplitude changes, and discrepancies between different sensor modalities. When detecting motion artifacts, the processing unit selectively weights the contribution of different signals or temporarily suppresses faulty segments, thus preserving overall data integrity. In certain implementations, additional motion measurement data can be used to improve the accuracy of artifact detection and filtering.

[0054] The processed and interpreted physiological data are then formatted for transmission by the wireless communication unit. Before transmission, the processing unit can apply data compression techniques to reduce bandwidth requirements while preserving important information. Security measures such as encryption and authentication protect the data during transmission. The wireless communication unit then transmits the processed data to an external device where it can be displayed, stored, or further analyzed.

[0055] The system is designed for continuous and energy-efficient operation, utilizing optimized computational paths to minimize power consumption. Task scheduling mechanisms balance processing load and energy consumption, ensuring sustained operation over extended periods. The integration of adaptive signal processing, multimodal data fusion, and anomaly detection into the processing unit enables the system to precisely monitor cardiorespiratory parameters in real time under a wide range of conditions, thereby fulfilling the system's functional objectives.

[0056] The continuous cardiorespiratory monitoring system consists of a flexible, multilayer bioelectronic skin patch. This includes a stretchable, elastomeric substrate, conductive interconnect layers, sensor layers, and an encapsulation layer. The elastomeric substrate is made of biocompatible materials such as polydimethylsiloxane (PDMS) or thermoplastic polyurethane and conforms mechanically to the skin surface. Embedded in the substrate are conductive traces made of materials such as graphene, silver nanowires, or thin gold films, arranged in a serpentine pattern to allow stretching and bending without interrupting electrical conductivity.

[0057] The sensor layer comprises several integrated sensors. A first set of electrodes is used to acquire electrocardiogram (ECG) signals by detecting the electrical activity of the heart. These electrodes are positioned to optimize signal acquisition in the chest area and are coated with conductive hydrogels to improve the impedance of the skin-electrode interface. A second set of piezoresistive or capacitive strain sensors detects the expansion and contraction of the chest associated with respiration. These strain sensors are arranged in a grid to capture multidirectional deformation patterns. Additionally, a photoplethysmographic (PPG) sensor is integrated, comprising light-emitting diodes and photodetectors to measure blood oxygen saturation and pulse wave characteristics.

[0058] The device also includes a temperature sensor integrated into the sensor layer to compensate for thermal fluctuations that could affect signal accuracy. The outputs of the sensor elements are routed via conductive connections to a signal acquisition unit containing low-noise amplifiers, analog-to-digital converters, and filter circuits. The signal acquisition unit is configured to sample the physiological signals at predefined frequencies and perform initial noise reduction using adaptive filtering techniques.

[0059] A processing unit operationally coupled to the signal acquisition unit is configured to perform feature extraction procedures, including R-wave detection in ECG signals, respiratory cycle segmentation, and pulse transit time estimation. The processing unit also utilizes machine learning-trained models to identify anomalies such as arrhythmias, apnea episodes, and hypoxemia. The processing unit is implemented in an energy-efficient microcontroller or system-on-chip architecture to ensure continuous operation with minimal power consumption.

[0060] The system also includes a power unit with a thin-film battery or energy harvesting components such as thermoelectric generators or piezoelectric elements, enabling continuous operation. The power unit is integrated into the flexible structure and configured to supply all functional components with regulated energy.

[0061] The wireless transmitter is configured to transmit processed data to an external device, such as a smartphone or remote server, using communication protocols like Bluetooth Low Energy or WLAN. The transmitter features a flexible antenna that maintains its performance even under deformation. Data security is ensured by encryption protocols implemented in the processing unit.

[0062] The encapsulation layer, positioned over the sensor and connection layers, is made of a breathable and waterproof material to protect the internal components from environmental factors such as moisture and mechanical abrasion. The encapsulation layer is also gas-permeable to prevent skin irritation during prolonged wear.

[0063] The device is designed to adhere securely to the skin using a medical-grade adhesive, while also allowing for painless removal. Its overall thickness is submillimeters, ensuring minimal perception and maximum comfort. Thanks to its flexible design, the device can be worn continuously for extended periods without compromising signal quality.

[0064] The device is attached to the user's chest and continuously records cardiorespiratory signals using integrated sensors. These signals are processed in real time to extract relevant physiological parameters, which are then transmitted to an external system for monitoring and analysis. The system enables the early detection of abnormalities and supports telemedicine applications, thereby improving treatment outcomes and reducing the burden on the healthcare system.

[0065] The invention thus offers a comprehensive, flexible and reliable solution for continuous cardiorespiratory monitoring by combining advanced materials, sensor integration and intelligent data processing in a compact and portable device structure.

[0066] The present invention relates generally to the field of biomedical devices and wearable health monitoring technologies. In particular, it relates to a system and the associated device structure for the continuous monitoring of cardiorespiratory parameters using flexible bioelectronic skin sensors. The invention integrates advanced materials, multimodal sensor elements, signal acquisition circuits, and processing units to enable non-invasive, real-time monitoring of physiological signals. The described system is particularly suitable for long-term health monitoring, remote patient care, and the early detection of cardiorespiratory diseases in both clinical and non-clinical settings.

[0067] The drawing and the preceding description illustrate embodiments. Those skilled in the art will recognize that one or more of the described elements can be combined to form a single functional element. Alternatively, certain elements can be divided into several functional elements. Elements of one embodiment can be added to another. For example, the process flows described here can be modified and are not limited to the manner described herein. Furthermore, the actions of a flowchart need not be performed in the sequence shown; nor do all actions necessarily need to be carried out. Actions that do not depend on other actions can be performed in parallel with the other actions. The scope of protection of the embodiments is in no way limited by these specific examples. Numerous variations, whether explicitly stated in the description or not, such as...Differences in structure, dimensions, and materials are possible. The scope of protection of the embodiments is at least as comprehensive as described by the following claims.

[0068] The advantages, other benefits, and problem solutions have been described above with reference to specific embodiments. However, the advantages, benefits, problem solutions, and any components that can effect or enhance an advantage, benefit, or solution are not to be construed as critical, necessary, or essential features or components of the claims. REFERENCES 100 A system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors. 102 Flexible substrate 104 Variety of Sensor Elements 106 Conductive connection structure 108 Signal Acquisition Unit 110 processing units 112 Wireless Communication Unit 114 Drive unit

Claims

[1] A system for continuous cardiorespiratory monitoring using flexible bioelectronic skin sensors, the system comprising: a flexible substrate configured to conform to the surface of human skin; a multitude of sensor elements arranged within or above the flexible substrate and configured to detect physiological signals such as electrical cardiac activity, respiratory movement, and blood perfusion characteristics; a conductive interconnect structure embedded in the flexible substrate that electrically couples the multitude of sensor elements; a signal acquisition unit that is operationally connected to the multitude of sensor elements and is configured to amplify, filter, and digitize the acquired physiological signals; a processing unit that is operationally coupled with the signal acquisition unit and is configured for signal processing, feature extraction and estimation of physiological parameters; a wireless communication unit that is operationally connected to the processing unit and configured to transmit processed physiological data to an external device; and A power supply unit integrated into and configured within the flexible substrate provides the system with electrical energy. The flexible substrate and sensor elements are arranged to maintain adaptable and continuous contact with the skin, reducing motion-related artifacts and improving signal quality during continuous monitoring. [2] System according to claim 1, wherein the flexible substrate comprises an elastic, biocompatible material selected to have mechanical properties similar to those of human skin, thereby enabling stretchability, flexibility and long-term wearability without delamination or discomfort, and wherein the substrate further comprises a multilayer structure including a base layer, a conductive intermediate layer and an encapsulation layer. [3] System according to claim 1, wherein the plurality of sensor elements comprises a set of electrodes configured to detect electrical cardiac activity, wherein the electrodes are formed from conductive materials and coated with a hydrogel interface layer to reduce skin-electrode impedance and improve signal detection stability over longer periods of time. [4] System according to claim 1, wherein the plurality of sensor elements further comprises at least one strain-sensitive element configured to detect the mechanical deformation of the thoracic region associated with the respiratory cycles, wherein the strain-sensitive element comprises a piezoresistive or capacitive structure arranged in a deformable pattern to detect multidirectional expansion and contraction. [5] System according to claim 1, wherein the plurality of sensor elements further comprises an optical sensor arrangement comprising at least one light-emitting element and at least one photodetector for measuring blood volume changes and thereby enabling the estimation of pulse characteristics and oxygen saturation levels. [6] System according to claim 1, wherein the conductive interconnect structure comprises stretchable conductor tracks arranged in serpentine or fractal geometry to maintain electrical continuity under mechanical deformation, and wherein the conductor tracks are formed from materials such as metallic thin films, nanowire networks or carbon-based conductive materials. [7] System according to claim 1, wherein the signal acquisition unit comprises a low-noise amplification circuit for amplifying weak physiological signals, an analog filter circuit for eliminating baseline deviations and high-frequency noise, and an analog-to-digital converter circuit for converting processed analog signals into digital signals with a predefined sampling rate. [8] System according to claim 1, wherein the processing unit is configured to perform methods for recognizing characteristic features from the detected signals, including identifying cardiac cycle events, segmenting respiratory cycles and estimating temporal relationships between cardiac and respiratory signals. [9] System according to claim 1, wherein the processing unit is further configured to analyze the extracted features in order to identify abnormal physiological conditions such as irregular heart rhythms, abnormal breathing patterns and reduced blood oxygen levels based on predefined thresholds or trained computational models. [10] System according to claim 1, wherein the wireless communication unit comprises an energy-saving transceiver configured for data transmission using short-range or long-range communication protocols, and wherein the unit comprises a flexible antenna structure integrated into the flexible substrate to maintain transmission performance even when deformed.

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