Flexible Piezoelectric Sensor Research Articles

Deep Learning Enabled Early Predicting Cardiovascular Status Using Highly Sensitive Piezoelectric Sensor of Solution‐Processable Nylon‐11

AbstractCardiovascular diseases are found as one of the major cause of deaths globally, these can be reduced substantially if early‐stage detection and intervention is possible. Regular monitoring of the arterial pulse is one of the possible solutions, however, existing technologies have put limitations, due instability in continuous monitoring, lack of information in real‐time recording of cardiovascular parameters and bulky instruments. A highly sensitive flexible piezoelectric sensor of nylon‐11 fabricated is introduced from simple solution processable technique. Which consists of a highly sensitive, flexible, conformable piezoelectric film, owing to its high mechanosensitivity (≈225 mV N−1) in the subtle pressure range (0.001–1 kPa), and fast responsivity (≈4 ms), it is tested for assessing risk factors of cardiovascular diseases based on arterial pulse data. It is integrated with the internet of things (IoT) via system on a chip to facilitate remote healthcare monitoring. Deep learning algorithms is further interfaced with sensor for early detect and predict cardiovascular risks, showing an accuracy of >94% for predicting cardiovascular status. This piezoelectric sensor equipped with artificial intelligence and IoT has potential for monitoring the risk analysis of the cardiovascular diseases, daily activities, and facilitate to early predict the anomalous physiological changes in the body.

A Review on PVDF Nanofibers in Textiles for Flexible Piezoelectric Sensors

Textiles are turning into a suitable next-generation sensing platform because of their good breathability, softness, and structural elasticity. Besides, research on self-powered piezoelectric sensors is a hot topic in wearable applications; they can perform long-term sensing and monitoring. Therefore, this paper mainly reviews the development progress of PVDF-based textiles on flexible piezoelectric sensors. In this paper, we first introduce the principle of the piezoelectric effect and the classification of piezoelectric materials; then we summarize the structure and characteristics of nanofiber mat-based, yarn-based, and fabric-based flexible piezoelectric sensors and the approaches that are employed to fabricate PVDF-based textile piezoelectric sensors such as melt spinning, electrospinning, and stretch forming processes, and so on. At last, we review their applicability in the application of electronic skin, human–computer interaction, healthcare, and human movement monitoring and demonstrate the facing difficulties and the future research directions of PVDF-based textile flexible sensors.

Graphene doping to enhance the mechanical energy conversion performances of GR/KNN/P(VDF-TrFE) flexible piezoelectric sensors.

Flexible piezoelectric composite, combining high piezoelectricity of filler and flexibility of polymer, provides a new research idea for developing flexible piezoelectric sensors (FPSs) with high piezoelectric output performance. FPSs based on GR/KNN/P(VDF-TrFE) three-phase composites are fabricated via doping a mass fraction of 15 wt% potassium sodium niobate (KNN) ceramic powder and various contents of graphene (GR) nanosheets into a P(VDF-TrFE) matrix. We find that an appropriate amount of GR is responsible for the enhanced crystallinity and β-phase of P(VDF-TrFE). When the GR content is 0.15 wt%, the three-phase composite film exhibits a dielectric constant (εr) of 20.9 and a quasi-static piezoelectric constant (d33) of -28.4 pC N-1. Under three different test scenarios of a ball drop experiment, a surface of the mouse wheel, and an action of 2.5 MPa external stress, this GR/KNN/P(VDF-TrFE)-based FPS shows high piezoelectric output voltages of 7.4 V, ∼2.0 V, and 15.4 V, respectively. Moreover, the FPS retains its performance even after an extended period of cantilever vibration cycles (2200). Thus, the conductive filler GR is responsible for promoting the energy conversion performance of the piezoelectric polymer, which also provides an application candidate of this GR/KNN/P(VDF-TrFE) film in FPSs.

Lead-free bimetallic oxide loaded on reduced graphene oxide‒poly(dopamine) hybrid nanocomposite with enhanced crystallinity and piezoelectric performance

The increased demand for electricity with low environmental impact has prompted researchers to find solutions to obtain the maximum output. This effort has imparted a significant focus on piezoelectric materials owing to their high piezoelectric coefficient and electromechanical coupling factor. In this study, reduced graphene oxide encapsulated with polydopamine and incorporated with zinc manganate hybrid nanocomposite (rGO‒pDA‒ZnMnO 3 HNC) was prepared. The as-prepared HNC, of different weight percentages, was blended with 15 wt% poly(vinylidene fluoride) (PVDF) to form different PVDF@rGO‒pDA‒ZnMnO 3(R) thin films. Subsequently, the flexible piezoelectric sensors (FPSs) were fabricated by a solution-casting method. The as-prepared HNC and thin films were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The PXRD data revealed the increased degree of crystallinity of the thin films from 54% to 68% with the increase in filler loading. The β-phase of PVDF also increased, as obtained from the FT-IR analysis. Electrical characterization of the prepared FPSs was carried out by estimating the sensitivity of the devices on different loads. The acquired response at a force of 1 N for PVDF@rGO‒pDA‒ZnMnO 3(0.2 wt%) improved by 44% than that of PVDF@rGO‒pDA‒ZnMnO 3(0 wt%) . The force applied by the finger on the device also generated voltages, which were used to charge the capacitor, thereby used to glow the light-emitting diodes with amplifications. These promising results demonstrate the potential for developing lead-free efficient piezoelectric nanogenerators for energy-harvesting applications and self-powered devices.

Recent development of piezoelectric biosensors for physiological signal detection and machine learning assisted cardiovascular disease diagnosis.

As cardiovascular disease stands as a global primary cause of mortality, there has been an urgent need for continuous and real-time heart monitoring to effectively identify irregular heart rhythms and to offer timely patient alerts. However, conventional cardiac monitoring systems encounter challenges due to inflexible interfaces and discomfort during prolonged monitoring. In this review article, we address these issues by emphasizing the recent development of the flexible, wearable, and comfortable piezoelectric passive sensor assisted by machine learning technology for diagnosis. This innovative device not only harmonizes with the dynamic mechanical properties of human skin but also facilitates continuous and real-time collection of physiological signals. Addressing identified challenges and constraints, this review provides insights into recent advances in piezoelectric cardiac sensors, from devices to circuit systems. Furthermore, this review delves into the integration of machine learning technologies, showcasing their pivotal role in facilitating continuous and real-time assessment of cardiac status. The synergistic combination of flexible piezoelectric sensor design and machine learning holds substantial potential in automating the detection of cardiac irregularities with minimal human intervention. This transformative approach has the power to revolutionize patient care paradigms.

Flexible Piezoelectric Tactile Sensor With Cilia-Inspired Structures Based on Electrospun PVDF/Fe3O4 Nanofibers

Flexible tactile sensors have promising applications at the field of intelligent robotics. However, manufacturing flexible tactile sensors with excellent stability and high sensitivity remain a great challenge. In the present work, polyvinylidene fluoride (PVDF)-based nanofibers are prepared by electrospinning loaded with Fe3O4 nanoparticles (NPs). X-ray diffraction (XRD) and attenuated total reflection Fourier transform infrared spectroscope (ATR-FTIR) results indicate that the addition of Fe3O4 NPs promotes the generation of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -phase in PVDF polymer, which greatly improves piezoelectric properties of composite nanofibers. Simultaneously, a flexible piezoelectric tactile sensor with cilia-inspired structures (PTSCS) based on PVDF/Fe3O4 nanofibers is proposed, which consists of the substrate with cilia structures, Ag electrodes, composite nanofiber membrane, and nanofiber protective layer. The PTSCS demonstrates a higher output voltage compared to sensors with bump and planar structures, which also exhibits high robustness, with a stable output after 30000 cycles of vibration testing. More importantly, the PTSCS demonstrates superior performance in recognizing surface texture and temperature of objects. The flexible PTSCS has potential use in areas such as intelligent soft robotics and material recognition.

High-performance microcone-array flexible piezoelectric acoustic sensor based on multicomponent lead-free perovskite rods

<h2>Summary</h2> Piezoelectric materials can serve as favorable candidates for future cochlear implants. However, most piezoelectric hearing devices until now have failed to simultaneously provide high sensitivity, desired flexibility, broad frequency selectivity, and biocompatibility. Herein, inspired by human outer ear hair cells, we meet these issues by introducing a microcone patterning array strategy based on novel lead-free, multicomponent rod-shaped niobate piezoelectric materials with a morphotropic phase boundary. The output voltage of the rod-based, flexible piezoelectric acoustic sensor (FPAS) is nearly 300% of that of the isotropic particles. The microcone patterning FPAS with stable performance in harsh environments shows high sensitivity (39.22 mV Pa⁻¹⋅cm⁻²) due to the significant enhancement of sound energy absorption and can record sound signals, recognize audio signals, and realize human-computer interactions. Our work demonstrates that the FPAS holds promise for various applications, such as the Internet of Things (IoT), cochlea implants, wearable acoustic equipment, and human-computer interaction.

Multi-material freeform 3D printing of flexible piezoelectric composite sensors using a supporting fluid

Three-dimensional (3D) printed flexible piezoelectric devices featuring conformal or freeform geometries show great potential for being fabricated into wireless sensors and energy harvesters with tailorable mechanical stiffness and piezoelectric response. In our work, supporting fluid-assisted multi-material extrusion-based 3D printing technology has been successfully utilized to fabricate flexible conformal or freeform piezoelectric composite sensors with integrated electrodes. The printing technique relies on the extrusion of two paste-like materials: piezoelectric and conductive composite inks. A comprehensive characterization of the inks (i.e., piezoelectric or conductive behaviors, rheological and mechanical properties) and the rheological behavior of the supporting fluid are performed. Polydimethylsiloxane (PDMS)/30 vol% lead zirconate titanate (PZT), PDMS/25 vol% silver (Ag) and mineral oil/6% (w/v) fumed silica are the formulations for piezoelectric ink, conductive ink and supporting fluid, respectively. Three types of piezoelectric composite demonstrators which are a multi-layer planar film, a conformal non-planar hemisphere and a 3D structure composed of six spirals printed vertically between two hexagon layers (freeform spiral-hexagon), are fabricated and tested under tension or compression tests. The piezoelectric performance is consistent with the applied stress in all the tests. For example, the freeform spiral-hexagon piezoelectric sensor has a peak-to-peak voltage output of 86.39 ± 1.145 mV when it is subjected to a cyclic compression force at 8 Hz for more than 800 cycles. The dimensional accuracy measurements using an optical microscope and the microstructure images taken using a scanning electron microscope (SEM) show that the fabricated 3D structures have good shape fidelity (with a maximum relative error of ~3.5%) when compared to the designed models. Our fabrication approach opens a new way to fabricate conformal and freeform piezoelectric structures with integrated electrodes from flexible composites for sensing and energy harvesting applications.

High performance waterproof-breathable fully flexible tactile sensor based on piezotronics coupled OFET

As obtaining flexible tactile sensors with high sensitivity, waterproofness and breathability at the same time is still a huge challenge, which limits their application in advanced fields such as human prosthetics and robotic arms. Herein, a fully flexible piezoelectric tactile sensor with high-performance, energy-efficient, waterproof, and breathable was constructed by capacitive coupling the β-PVDF nanofiber membrane (NM) with electro-mechanical conversion function and organic field effect transistor (OFET) device with signal amplification function. The inherent waterproofed β-phase PVDF NM was fabricated by advanced electrospinning process, such morphology with thousands of micropores not only gives the device excellent breathability, but also increases the deformation tolerance and accelerates the respond/recovery time, so that the obtained device can be bent at will without affecting its performance. At the same time, under the guidance of pizotronics, the charge generated by PVDF membrane based on piezoelectric effect polarization was sufficient to drive the OFET device, the as-fabricated sensor shows great sensing performance in monitoring human physiological signals without applying a gate voltage. Such device exhibits excellent pressure sensitivity, detection limit, and response time of 7.94 KPa-1, 48.54 Pa and 105 ms, respectively, which may become promising device in smart electronic skins, human motion detection, and human−machine interaction.

Dynamic modeling and analysis of flexible micro-porous piezoelectric sensors applicable in soft robotics

With recent advances in system integration technologies, numerous efforts have been made to develop soft piezoelectric sensors for various engineering and healthcare applications. Using flexible and sensitive materials is crucial for designing soft sensors in order to maximize their efficiency and integrability. Micro-porous PU-PZT composite is a recently designed piezoelectric particulate composite material with an improved flexibility and piezoelectric voltage coefficient over common piezoelectric ceramics that makes it a promising candidate for application in soft sensors. In this study, we investigate the dynamic response and sensitivity of the micro-porous PU-PZT composite for applications in soft sensors in both 33 and 31 modes using energy methods. By using the effective field method, the micro-porous PU-PZT composite material properties were extracted and optimized based on the partially experimentally measured properties in order to get a complete picture of the properties of the material. In addition, the effects of changing the sensor geometry by varying the thickness and adding an extra layer between the piezoelectric layers are studied. Finally, a large area sensor based on micro-porous PU-PZT composite is simulated in finite element software, and the effect of several parameters on sensor’s performance is investigated. Dynamic analysis of the sensor shows high sensitivity in both 31 and 33 modes which is a significant improvement compared to the commonly used bulk piezoelectric ceramics. This work has demonstrated that due to the high output voltage and structural flexibility of the micro-porous PU-PZT composite, a flexible large-area sensor would be a suitable choice for artificial skins and smart gloves.

A Flexible Multifunctional PAN Piezoelectric Fiber with Hydrophobicity, Energy Storage, and Fluorescence.

Lightweight, flexible, and hydrophobic multifunctional piezoelectric sensors have increasingly important research value in contemporary society. They can generate electrical signals under the action of pressure and can be applied in various complex scenarios. In this study, we prepared a polyacrylonitrile (PAN) composite fiber doped with imidazolium type ionic liquids (ILs) and europium nitrate hexahydrate (Eu (NO3)3·6H2O) by a facile method. The results show that the PAN composite fibers had excellent mechanical properties (the elongation at break was 114% and the elastic modulus was 2.98 MPa), hydrophobic self-cleaning ability (water contact angle reached 127.99°), and can also emit light under UV light irradiation red fluorescence. In addition, thanks to the induction of the piezoelectric phase of PAN by the dual fillers, the composite fibers exhibited efficient energy storage capacity and excellent sensitivity. The energy density of PAN@Eu-6ILs reached a maximum of 44.02 mJ/cm3 and had an energy storage efficiency of 80%. More importantly, under low pressure detection, the sensitivity of the composite fiber was 0.69 kPa-1. The research results show that this PAN composite fiber has the potential to act as wearable piezoelectric devices, energy storage devices, and other electronic devices.

Highly sensitive and wearable bionic piezoelectric sensor for human respiratory monitoring

Flexible piezoelectric sensors hold great promising for applications in electronic skin (E-skin), wearable devices, and biomedical devices. However, it is still challenging to apply flexible piezoelectric sensors to respiratory health monitoring which requires an extremely low detection limit. To address this challenge, a flexible bionic piezoelectric sensor inspired by the lateral line structure of fish is proposed in this study. Benefited from the excellent piezoelectric effect of polyvinylidene fluoride (PVDF) and the bionic structural design, the proposed sensor has a low detection limit of 0.0005 N and can be conformal with a cylindrical surface. In addition, the sensor can accurately sense the pressure at a high sensitivity of 0.24 V N−1 with a fast response time of 4 ms and long-term repeatability of 4000 cycles. Through the design of back-end circuitry, the bionic sensor is capable of accurately monitoring of various respiratory states, such as apnea, coughing, and deep breathing. These results show that our sensor has great potential as a wearable device in the field of respiratory health monitoring, and is also highly inspiring for designing other types of flexible sensors.

Barium titanate–bismuth ferrite/polyvinylidene fluoride nanocomposites as flexible piezoelectric sensors with excellent thermal stability

Flexible piezoelectric sensors based on barium titanate–bismuth ferrite/polyvinylidene fluoride BT–BFO/PVDF nanocomposites were prepared via electrospinning for pitch-catch applications. The 20% BT–BFO/PVDF piezoelectric sensor had the 75% β phase and exhibited a dielectric constant of 55.71, a dielectric loss of 0.035 and a signal voltage of 3.35 V at 100 kHz, indicating significant improvement compared to traditional PVDF sensors. Moreover, the sensor can maintain a stable signal voltage of 2.0 V and dielectric constant variation of less than 15%, even when the temperature gradually increased from 20 ℃ to 120 ℃. The flexible piezoelectric sensor that can endure temperature variations shows great potential in mass concrete.

Flexible piezoelectric sensor based on PVDF-TrFE/Nanoclay composite nanofibers for physiological micro-vibration signal sensing

Vibrations of human organs and tissues contain lots of useful physiological information, and these physiological vibrations can be called physiological micro-vibration signals (PMVS). Here, we designed wearable piezoelectric sensors (PMVS sensors) based on poly (vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)/(Na, Ca)0.33(Al, Mg)2(Si4O10)(OH)2·nH2O (Nanoclay) electrospinning nanofibers, parallel-stripes electrode integrated with impedance matching circuit, and arc-spring polyimide (PI) substrate for PMVS monitoring. The PMVS sensors with a tailor-made data acquisition system and a purpose-designed Android APP made up the PMVS acquisition system to collect throat vibration, pulse, respiration, heartbeat, and gait signals. The acquired data was compared with that by Polysomnography (PSG), and the time–frequency information of the two was highly consistent. Separate from traditional physiological signal monitoring equipment (e.g., PSG), the PMVS monitoring system obtains more information with fewer constraints. In parallel, the proposed PMVS monitoring system can acquire, quantify, and remotely monitor the physical health data, establishing a promising platform for next-generation homecare.

Incorporation of ZnO encapsulated MoS2 to fabricate flexible piezoelectric nanogenerator and sensor

Polymer based piezoelectric composite has attracted much attention in recent years due to its applicability in the manufacture of piezoelectric nanogenerators and sensors, high piezoelectric performance, high flexibility and easily shaping properties. In this work, ZnO with good piezoelectric properties was grown on the exfoliated MoS2 nanosheets by employing in situ polymerization, which was then incorporated in PVDF to prepare PVDF/MoS2@ZnO piezoelectric composite film. The effect of various contents of ZnO on its structure and properties was emphatically discussed, as well as the mechanical energy collection and sensing performance. The results show that ZnO has been deposited on the surface of MoS2 nanosheet to form heterostructure (MoS2@ZnO), as well as that the MoS2@ZnO can effectively promote the transformation from α phase to β phase in PVDF, by which the content of β phase can be increased from 6.2 ± 2.5 % to 54.3 ± 2.7 %. It also exhibits excellent mechanical performance and flexibility with the tensile strengthen of 37.64 ± 5.12 MPa and elongation at break of 9.77 ± 1.57 %. The longitudinal piezoelectric constant (d33) of the composite film reached a maximum value of 31 ± 4 pC·N-1. The open-circuit voltage (VOC) and short-circuit current (ISC) of PVDF/MoS2@ZnO piezoelectric composite film reach as high as 6.22 V and 528 nA under the acting force of 100 KPa, respectively. It can charge a 1.0 μF commercial capacitor to 1.81 V in 400 s. Finally, a flexible piezoelectric sensor was fabricated to collect the pressure signals induced from human body movement (the bending of fingers, wrists and elbow joints), presenting excellent sensitive piezoelectric response with the VOC of about 0.41 V, 0.22 V and 0.32 V, respectively. The found performance indicates its feasibility for the application in wearable intelligent devices.

Deep learning-based noise robust flexible piezoelectric acoustic sensors for speech processing

Flexible piezoelectric acoustic sensors (f-PAS) have attracted significant attention as a promising component for voice user interfaces (VUI) in the era of artificial intelligence of things (AIoT). The signal distortion issue of highly sensitive biomimetic f-PAS is one of the most challenging obstacle for real-life application, due to the fundamental difference compared with the conventional microphones. Here, a noise-robust flexible piezoelectric acoustic sensor (NPAS) is demonstrated by designing the multi-resonant bands outside the noise dominant frequency range. Broad voice coverage up to 8 kHz is achieved by adopting an advanced piezoelectric membrane (Nb-doped PZT; PNZT) with the optimized polymer ratio. Deep learning-based speech processing of multi-channel NPAS is demonstrated to show the outstanding improvement in speaker recognition and speech enhancement compared to a commercial microphone. Finally, the NPAS filtered the crowd condition noises, showing independent speaker’s speeches can be identified and digitalized simultaneously.

Flexible Self-Powered Tactile Sensors Based on Hydrothermally Grown ZnO Nanorods

Flexible tactile sensors with high sensitivity and good flexibility are urgently required in modern biomimetic robots’ electronic skin, and artificial intelligence interaction. In this work, a flexible piezoelectric tactile sensor was fabricated using hydrothermally grown ZnO nanorods (ZnO NRs) on Cu-coated polyimide (PI) substrate. Structural and morphological properties of the ZnO NRs were investigated by SEM, XRD. The piezoelectric response properties of the sensors by using the pasted Cu/PI electrode and directly screen-printed Ag electrode were compared. The results show the sensor with the screen-printed Ag electrode exhibits a high sensitivity of 974 mV/N, which is higher than the pasted Cu/PI electrode, and the response of all sensors to the applied pressure is almost linear in the range of 0.1-1 N. Meanwhile, the sensor can be employed to detect human movements such as bending/stretching motion of fingers and the vibration of the vocal cords and pulse, and realize the conversion from mechanical energy to electrical energy. It is demonstrated that the sensor has great potential applications in wearable health monitoring systems and self-powered devices.

Flexible, stable and durable polydopamine@lead zirconate titanate/polyimide composite membranes for piezoelectric pressure sensors and limb motion monitoring

Flexible piezoelectric pressure sensors have been paid great attention in wearable electronic devices, obtaining mechanical energy and driving portable devices. Presently, membranes based on piezoelectric ceramic/polymer composite materials encounter problems such as filler agglomeration and surface defects, which affects the energy conversion performance of piezoelectric devices. Herein, the surface of lead zirconate titanate (Pb(Zr0.52Ti0.48)O3, PZT),was modified by coupling agent-polydopamine (Pdop), and combined with the polyimide (PI) matrix by in-situ polymerization to form a uniform Pdop@PZT/PI composite. This polydopamine modification method increases the compatibility between the two components, and promotes the dispersion of PZT in the polyimide matrix more uniform. Under the external force of 10 N, the maximum open circuit voltage of Pdop@PZT/PI-based piezoelectric pressure sensor (PPS) can reach 12.8 V. In addition, the sensitivity of the sensor is 1.4 V/N (0.24 V/kPa), which can maintain a stable output voltage under different frequencies of external force. After 10,000 cycles of periodic impacting/releasing, the open circuit voltage of PPS remained stable, indicating that the device has excellent stability and durability. It has the potential to be used as self-powered wearable sensors and detect human motion in daily life.

Warranty Seal Deformation Identification for Product Warranty Violation.

Product warranty seals or stickers are criteria for after-sale warranty services. The unauthorized removal or modification of a seal will void the warranty. So far, there is no detection method to confirm the warranty, other than the visual inspection of the deformation of the seal. Hence, a system to detect, read, and record the ’warranty’ seal deformation is presented in this paper. A flexible piezoelectric sensor was used to determine the mechanical impacts of the seal. Three major impacts are discussed and evaluated in this paper—partial removal, complete removal, and drop deformations of the seal. These impacts were compared with the ambient responses to distinguish the conditions. All three impact cases show distinct characteristics in terms of sensor values, pulses, and pulse widths. For partial removal and complete removal of the seal, both cases exhibited maximum sensor values but differed in pulse and pulse width. A partially removed seal experienced the maximum number of pulses while complete removal experienced the maximum pulse width. However, if the seal experienced a drop impact, it showed lower sensor values, with the lowest pulse and pulse width. Hence, an algorithm was applied to generalize the conditions and decisions of warranty violations.

Flexible, Equipment-Wearable Piezoelectric Sensor With Piezoelectricity Calibration Enabled by In-Situ Temperature Self-Sensing

Flexible piezoelectric sensors have attracted much attention due to good dynamic response, high sensitivity, and self-powered sensing advantages. However, piezoelectric outputs are usually affected by temperature variation, thus limit their applications on industrial intelligent equipment. Here, a new flexible piezoelectric sensor with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> temperature sensing and piezoelectricity calibration function is developed. The sensor can calibrate the piezoelectric output based on temperature to achieve high-accuracy sensing capability. It consists of a flexible polyimide substrate, S-shaped platinum interdigital electrodes and aligned piezoelectric fibers. The designed S-type electrode with thermosensitive effect measures the temperature <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in-situ</i> , and then the piezoelectric strain output from P(VDF-TrFE) fibers is calibrated according to the temperature. The temperature sensor has a high sensitivity of 19.2 Ω/°C with good linearity, and keeps good accuracy under bending deformation. When the working temperature range is 25 °C–60 °C, the sensor has a good piezoelectricity calibration effect, so that it maintains a stable sensitivity of 244 mV/μϵ without being affected by temperature. Furthermore, this article systematically studied the influence of temperature on piezoelectric output, and established a calibration method to improve the accuracy of piezoelectric output under temperature changes. Finally, the flexible integrated sensor was conformally attached on the bearing surface to <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> sensing temperature and micro-strain. The structural design and piezoelectricity calibration method can promote the application of flexible piezoelectric sensors in the industrial field.