Resonant pressure sensors (RPSs) are key for high-precision MEMS pressure measurement, but traditional off-chip temperature sensors (OFTS) suffer heat conduction lag under rapid temperature change, limiting accuracy in aircraft rapid maneuvering. To address this bottleneck, this study proposes a novel RPS scheme integrating resonant and diode temperature-sensitive structures. By combining an on-chip integrated temperature sensor (OCITS) and a frequency-temperature dual-parameter fourth-order polynomial compensation algorithm, high-precision pressure measurement under rapid temperature change is achieved. A COMSOL multiphysics model compares OCITS and OFTS responses at 0.1 degrees C-10 degrees C/min: at 1 degrees C/min, OCITS exhibits <= 50 ms delay (versus 946 s for OFTS) with <= 0.3 degrees C tracking error; at 10 degrees C/min, OCITS maintains synchronization while OFTS loses validity (error >62.4 degrees C). Prototypes were fabricated via the DRIE bulk silicon process and tested under dynamic temperature-pressure conditions. Experiments show: OCITS achieves synchronous response at 10 degrees C/min, within -55 degrees C to 100 degrees C and 3.5-285 kPa, comprehensive accuracy reaches 0.0038% full scale (FS) which is 3.68 times higher than that of OFTS (0.014% FS). This work addresses the pressure measurement bottleneck of aircraft during rapid maneuvering, providing a reliable solution for high-precision MEMS sensors in aerospace.

This article presents an integrated flexible ice-sensing sensor array system based on microwave resonance. The system combines ice detection with electric heating de-icing, establishing a 3-D electromagnetic model for the microwave resonator. A novel interdigital circular complementary split-ring resonator (ICCSRR) structure [evolved from complementary split-ring resonator (CSRR)] enables high-precision ice thickness detection (0-8 mm, +/- 0.1-mm resolution, and <300-ms response). Innovatively, the resonant microstrip integrates with a flexible heating film to form a self-sensing-self-heating composite unit, using impedance phase characteristics for real-time de-icing feedback and dynamic power adjustment (6-10 W). Its fully flexible design suits drone icing areas, while array-based detection provides multipoint ice shape data. Verified via an ice simulation-S21 testing platform, the system distinguishes 0.1-mm ice at-21 degrees C, removes 4-mm ice within 10 s at-20 degrees C in high-power mode, and prevents icing via low-power pre-activation. Sensors offer synchronous de-icing progress feedback, demonstrating excellent ice-sensing and de-icing performance.

This paper introduces the new structural optimization framework utilizing the Non-dominated Sorting Genetic Algorithm II to optimize the performance of a MEMS disk resonant gyroscope. Under the premise that the inherent relationship between the structure and performance of the gyroscope remains unclear, the primary objective of the framework is to mitigate frequency split, while preserving an elevated quality factor and enhancing mechanical sensitivity. By iteratively refining critical parameters such as ring width, electrode gap width, and spoke dimensions, the optimized structure exhibits markedly improved performance. Specifically, it achieves an 89 % reduction in frequency split, and a 66% enhancement in quality factor, and a 715% improvement in mechanical sensitivity. This study underscores the efficacy of the proposed methodology in advancing the design and work efficiency of MEMS gyroscopic systems.

AbstractThe design of the microelectromechanical system (MEMS) disc resonator gyroscope (DRG) structural topology is crucial for its physical properties and performance. However, creating novel high-performance MEMS DRGs has long been viewed as a formidable challenge owing to their enormous design space, the complexity of microscale physical effects, and time-consuming finite element analysis (FEA). Here, we introduce a new machine learning-driven approach to discover high-performance DRG topologies. We represent the DRG topology as pixelated binary matrices and formulate the design task as a path-planning problem. This path-planning problem is solved via deep reinforcement learning (DRL). In addition, we develop a convolutional neural network-based surrogate model to replace the expensive FEA to provide reward signals for DRL training. Benefiting from the computational efficiency of neural networks, our approach achieves a significant acceleration ratio of 4.03 × 105 compared with FEA, reducing each DRL training run to only 426.5 s. Through 8000 training runs, we discovered 7120 novel structural topologies that achieve navigation-grade precision. Many of these surpass traditional designs in performance by several orders of magnitude, revealing innovative solutions previously unconceived by humans.

In recent decades, the UAV industry has rapidly developed, with UAVs finding applications in various fields. With the large number of UAVs being put into use, icing problems ensue. In this paper, a microwave icing sensor with a flexible array is introduced for measuring icing on the windward surface of UAVs, and a complementary coupled split-ring resonator (CCSRR) structure sensitive to ice thickness is proposed based on the evolved CSRR structure. The sensor film consists of a metal defect microstrip, a polyimide film, a flexible medium and a metallic ground. The resonance frequencies corresponding to different ice thicknesses are obtained by icing the surface of the sensor defective microstrip structure and then observing the transmission coefficient (S21) fed back from the experimental setup, and a functional relationship between the ice thickness and resonance frequency is established. Compared with traditional icing sensors, flexible structures can better adhere to the surface of a UAV, and the array-based design expands the detection capability of the sensor. This sensor not only measures the thickness of a single point, but also provides feedback on the ice morphology in the icing-sensitive area, which is convenient for the operator to formulate a deicing program.

Chip technology has become a bottleneck restricting the development of high-quality in China,and the high-performance micro-sensor chip based on micro-electro-mechanical system(MEMS)technology is one of the bottlenecks devices in Europe and America."If you want to do something good,you must first improve your tool",similar to microelectronics chips,design and manufacturing technology is also the key to restricting the performance of MEMS chips.Firstly,starting from MEMS design methods and tools,reviews the development process of MEMS design methods from structured design methods of fixed processes to pan-structured design methods of arbitrary processes,introduces the advantages of arbitrary process design methods,introduces the mainstream commercial MEMS design tools in the world,and compares the advantages and disadvantages of typical design tools.Secondly,the characteristics and challenges of MEMS manufacturing technology are introduced,and several typical customized manufacturing technologies in the world and the single mask and selective release manufacturing methods proposed by Northwestern Polytechnical University are emphatically analyzed.Then the advantages of batch manufacturing technology are analyzed and the common batch foundry methods and typical batch foundry processes in China are given.Finally,the necessity of high-end MEMS design and manufacturing integration is pointed out,in order to provide reference for the development of China's MEMS mass manufacturing.

This paper proposes a flexible double-sided attached microwave sensor film for real-time measurement of the liquid dielectric constant, and proposes a nested-complementary split ring resonator(NCSRR)structure with high sensitivity and quality factor values that is based on the structure evolution of a complementary split ring resonator(CSRR). The sensor films are composed of a ground film with an NCSRR structure and a U-shaped microstrip line film. By taking a borosilicate glass beaker and a polypropylene beaker as examples, two types of microwave sensors are formed by attaching films to both sides of the beakers. Lubricating oil with 0%- 25% water content is added to the beakers separately, and the dielectric constants of the mixture are characterized nondestructively by the transmission coefficient (S21) of the device. According to the mathematical model established from the measurement results, the resonant frequencies of both sensors are linearly and negatively correlated with the dielectric constant of the liquid to be measured, which proves that the sensor film can be attached to a substrate with arbitrary curvature to form a microwave resonant sensor.

This article reports a MEMS disk resonator gyroscope (DRG) with superior overall performance in terms of bias instability, measurement range, and size. Specifically, a fully filled electrodes MEMS DRG is proposed to improve sensing capacitance to 23.66 pF and drive capacitance to 6.14 pF. The DRG is fabricated using a wafer-level vacuum-package process and is controlled and sensed by a configurable ASIC, enabling a small footprint. The DRG achieves an angle random walk of 0.05°/√h and bias instability of 0.42°/h within a full scale of ±300°/s, making it a very promising solution for angular measurement in high-end industrial applications.

Icing has always been a problem for the aviation industry and the UAV sector. Small and accurate icing sensors can ensure the safety of critical parts of the aircraft and small UAVs in flight. This paper presents an Interdigital-complementary split-ring resonator sensor (ICSRR) that can distinguish water and ice with high accuracy and measure the thickness of ice. Compared with the traditional CSRR structure, the added Interdigital structure can measure ice thickness more sensitively. The sensor detects water and ice based on the change in resonant frequency measured in the scattering parameter S21 coefficient. A prototype sensor was built, and measurements were taken to verify the functionality of the sensor. First, the resonant frequencies under no-load were measured. Second, the process of water icing was characterized using the sensor. Finally, the accuracy of the sensor’s measurement of icing thickness was verified, and the data were fitted. The experimental results show that it is feasible to use the ICSRR sensor to monitor the icing condition and ice thickness.

This paper proposes an electrostatic-piezoelectric hybrid vibrational power generator with different frequency broadening schemes. Both the nonlinear frequency broadening mechanisms and the synergized effect of the electrostatic-piezoelectric hybrid structures are investigated. On the one hand, we adopt the curved fixture structure, which has a 25% increase in bandwidth compared with the ordinary stopper structure. On the other hand, by integrating the electrostatic structure, the half-power bandwidth of the piezoelectric cantilever beam is 16Hz to 20Hz, and the peak power is 3.6mW, the half-power bandwidth of the electrostatic structure is 14.5Hz to 19.5Hz, and the peak power is 2.2mW. This means that under the same space utilization, the performance is improved by 60%. In this paper, the hybrid generator's structure and performance are optimized, and finally the response bandwidth and performance are improved. In general, the device designed in this paper has advantages such as larger bandwidth and better performance.

Wearable electronics and electric skin attract increasing attention, which demand high transparency, extensibility, and biocompatibility. In this work, a transparent and highly stretchable pyramidal hydrogel-based triboelectric nanogenerator (HTG) for tactile sensation and neck movement detection is reported. Hydrogel can be easily stretched to 800% of the initial length. The output property of HTG could reach up to 360V and 1.27mW. Meanwhile, a slight signal like blowing could also be detected by the proposed device. Besides, the charging time of the capacitor reveals the dependence of output property and frequency. This work provides a brilliant method for self-powered physiological signal monitoring.

This paper reports a closed-loop MEMS disk resonator gyroscope (DRG) with configurable measurement range and bandwidth. A configurable ASIC is employed for the measurement range and bandwidth configuration and the design methods of measurement range and bandwidth are studied. By changing the registers of the ASIC, the measurement range is configured from 450 to 2250°/s, and the bandwidth is configured from 10 to 100 Hz. Meanwhile, experiments prove that increasing the measurement range or bandwidth will deteriorate the accuracy of the gyroscope to some degree.

In this paper, stretchable strain sensors with a controllable negative resistance sensitivity coefficient are firstly proposed. In order to realize the sensor with a negative resistance sensitivity coefficient, a stretchable stress sensor with sandwich structure is designed in this paper. Carbon nanotubes are added between two layers of silica gel. When the sensor is stretched, carbon nanotubes will be squeezed at the same time, so the sensor will show a resistance sensitivity coefficient that the resistance becomes smaller after stretching. First, nanomaterials are coated on soft elastomer, then a layer of silica gel is wrapped on the outside of the nanomaterials. In this way, similar to sandwich biscuits, a stretchable strain sensor with controllable negative resistance sensitivity coefficient has been obtained. Because the carbon nanotubes are wrapped between two layers of silica gel, when the silica gel is stretched, the carbon nanotubes will be squeezed longitudinally, which increases their density and resistance. Thus, a stretchable strain sensor with negative resistance sensitivity coefficient can be realized, and the resistivity can be controlled and adjusted from 12.7 Ω·m to 403.2 Ω·m. The sensor can be used for various tensile testing such as human motion monitoring, which can effectively expand the application range of conventional tensile strain sensor.

Wearable electronics and electric skin attract increasing attention, which demand high transparency, extensibility, and biocompatibility. In this work, a transparent and highly stretchable pyramidal hydrogel-based triboelectric nanogenerator (HTG) for tactile sensation and neck movement detection is reported. Hydrogel can be easily stretched to 800% of the initial length. The output property of HTG could reach up to 360V and 1.27mW. Meanwhile, a slight signal like blowing could also be detected by the proposed device. Besides, the charging time of the capacitor reveals the dependence of output property and frequency. This work provides a brilliant method for self-powered physiological signal monitoring.

In this paper, a first-order closed-loop mechatronics model of a micro-electromechanical system (MEMS) disk resonator gyroscope (DRG) with a configurable ASIC is established for closed-loop design and performance analysis. There are usually some nonlinear modules in the gyroscope mechatronics model, and it is difficult to design the closed-loop controllers using classical automatic control theory. An order-reduction method (ORM) based on the Laplace transform and inverse Laplace transform is proposed to linearize the nonlinear modules. The linearized model is proved to show good agreement with the original mechatronics model in terms of system response. The experimental verification was conducted to demonstrate the validation of this method.

In this paper, a flexible and stretchable energy harvester based on liquid-metal and fluorinated ethylene propylene (FEP) electret films is proposed and implemented for the application of wearable devices. A gallium liquid-metal alloy with a melting point of 25.0 °C is used to form the stretchable electrode; therefore, the inducted energy harvester will have excellent flexibility and stretchability. The solid-state electrode is wrapped in a dragon-skin silicone rubber shell and then bonded with FEP electret film and conductive film to form a flexible and stretchable energy harvester. Then, the open-circuit voltage of the designed energy harvester is tested and analyzed. Finally, the fabricated energy harvester is mounted on the elbow of a human body to harvest the energy produced by the bending of the elbow. The experimental results show that the flexible and stretchable energy harvester can adapt well to elbow bending and convert elbow motion into electric energy to light the LED in a wearable watch.

Analysing and minimizing energy loss is crucial for high performance disk resonator gyroscopes (DRGs). Generally, the primary energy loss mechanism for high vacuum packaged microelectromechanical system (MEMS) resonators includes thermoelastic damping, anchor loss, and electronic damping. In this paper, the thermoelastic damping, anchor loss, and electronic damping for our DRG design are calculated by combining finite element analysis and theoretical derivation. Thermoelastic damping is the dominant energy loss mechanism and contributes over 90% of the total dissipated energy. Benefiting from a symmetrical structure, the anchor loss is low and can be neglected. However, the electronic damping determined by the testing circuit contributes 2.6%-9.6% when the bias voltage increases from 10 V to 20 V, which has a considerable impact on the total quality factor (Q). For comparison, the gyroscope is fabricated and seal-packaged with a measured maximum Q range of 141k to 132k when the bias voltage varies. In conclusion, thermoelastic damping and electronic damping essentially determine the Q of the DRG. Thus, optimizing the resonance structure and testing the circuit to reduce energy loss is prioritized for a high-performance DRG design.

The turn-on bias behaviour of a Coriolis vibratory gyroscope (MCVG) is theoretically modelled, numerically simulated and experimentally verified in this paper. First, the bias-temperature relationship during the thermal start-up process is analytically established. Second, the bias-time characteristic is modelled by analyses of different transient responses via different pathways in the heat transfer process. Finally, an experimental verification method is proposed to verify the established turn-on bias model. The comparison proves the established model can predict the turn-on bias behaviour of MCVGs with an acceptable error of 9%. (C) 2018 Elsevier Ltd. All rights reserved.

Micromechanical gyroscope is a new type of gyroscope. In recent years, with the development of MEMS technology, its performance has been continuously improved. In this paper, based on the development status of multi?ring resonant micromechanical gyroscope, the sources of multi?ring resonant gyroscope and its advantages from single?ring to multi?ring structure are reviewed, and two new types of fully symmetric resonant disk gyroscope based on the principle of standing wave precession are introduced. Then, the process development route of the ring resonant micromechanical gyro?scope is summarized. From the early HARPSS process to the epitaxial Polysilicon encapsulation process, and then to the single?crystal Silicon thermos?compression bonding process with good material properties, which makes the performance of the multi?ring resonant gyroscope continuously improved, its advantages and disadvantages are analyzed. At last, the future of high technologies is prospected, the development direction of multi?ring resonant gyroscope is proposed.

The oscillation of the sense mode of the micro-machined Coriolis vibratory gyroscope (MCVG) with high quality factor (Q) is analyzed in this study and the corresponding force feedback control scheme is presented to suppress this oscillation. The controller consists of integrator and some filters, instead of the common but complicated demodulation and remodulation modules. Compared with using no oscillation suppression scheme, the proposed simplified oscillation suppression control scheme can achieve an improvement of the sense mode of the MCVG. The inband spectrum ripple of the angular rate output are improved from 51.4 dB to 4.23 × 10−4 dB. Correspondingly, these two performance parameters are improved by 370.4 and 186.2 times, which are higher than two orders of magnitude, respectively. Bias stability is improved from 9.72 deg/h to 2.5 deg/h. Test results prove that the proposed control scheme is effective in suppressing the oscillation.