Key Engineering Materials Vols. 562-565

Abstract: The paper describes the basic principle and structure of the resonator micro-optic gyro (RMOG), the influence of intensity variation of laser is analyzed for the first time. The relationship between the light intensity input the integrated optical resonator (IOR) and the slope at working range is simulated and analyzed by the optical field overlapping method. The amplitudes of the output square waveforms with different zero biases are simulated and analyzed. The experimental setup is constructed and tested, the test result shows that in order to reach the limited ultimate sensitivity of 15.5 deg/h, it is necessary to restrict the zero bias within 8.1 deg/s under open-loop output scheme.

Abstract: To meet a high-precision accelerometer resistance of temperature, humidity and other external noise, a new multi-ring cascade optical accelerometer structure is designed. The micro-ring resonator on the cantilever beam based on the photo-elastic effect and the contrast are fabricated with the same manufacturing process and size, which can effectively meet the consistency of the contrast and test micro-ring resonator on the cantilever. The one resonance point curve will split into two under the acceleration, thus the acceleration value can be obtained by detecting the wavelength of the two resonant points. By testing the cascade race-track shaped micro-ring resonator at different temperatures, the Q=10⁴, the test requirement of cascade race-track shaped micro-ring accelerometer in different environments is greatly met. The design can be widely applied to the occasions of penetration system with high impact, strong vibration and so on. And the anti-noise and anti-jamming features of the integrated miniaturized high-sensitivity MOEMS sensors are realized.

Abstract: The need for high throughput label-free multiplexed sensors for biological sensing has increased in the last decade. In this paper, a new surface stress-based polydimethylsiloxane (PDMS) membrane biosensor for cellular detection is designed and fabricated. The geometric parameters of the PDMS membrane are optimized through the finite element (FE) analysis. One fiber optic interferometer biosensor test system is built to test the characteristics of the biosensor. The biosensor is further functionalized using 11 Mercapto 1 undecanoicacid (MUA: SH-(CH2)10-COOH) and tested in contact with cells Escherichia coli (E. coli). The results of our experiments showed that cells can be detected based on the surface stress-based PDMS membrane biosensor. The new approach for cellular detection has good sensitivity and biocompatibility.

Abstract: With power voltage and capacity improved greatly, power transmission system put a higher demand on reliability and safe operation of electrical equipments. Electromagnetic sensors and other conventional detection equipment can no longer meet the needs of the power system, and new sensing measurement techniques led to optical current and voltage sensing technology. As their unique advantages, optical current sensing technology is get in-depth study and attention, and gradually used in power system engineering applications. Combined with domestic and foreign research progress of optical current sensor, we analyzed the basic principles of the photoelectric sensing technology and problems faced in power system applications and key technologies. Focused on sensing characteristic differences of photoelectric sensors and electromagnetic sensor, we analyzed the effects of photoelectric sensor on protection, monitoring and control, measurement systems in data processing and data transmission, and study the corresponding key technology. Combined with the development of modern power system, we prospect optical current sensor sensing technology opportunities and challenges in smart grid.

Abstract: Casimir had measured the Casimir force through experimental methods, and fitted the empirical formula between the plates. On its basis we analyse that when the gap of two separating surfaces achieves submicron in micro devices, the effect of the Casimir force to the micro-devices is great and this Casimir effect can not be ignored. The results show that: Considering the Casimir force or not, the extreme value of acceleration which can be detected by micro-accelerometer is different, and we have got the specific numerical fitting figure by Matlab .

Abstract: In MEMS, the size of micro-structure is usually in the micron and even nanoscale. It's easier to form capillary phenomenon than the macroscopic system. In view of this phenomenon, this article is based on the micro-mechanical gyroscope as the research object, to analyze the occurrence of capillary condensation of adhesion phenomenon. Firstly, we derive the Kelvin equation for capillary condensation, and then combination of the Kelvin equation introduce the capillary condensation of the adhesion phenomenon; Secondly, it analyzes the dynamics characteristics of its structure existing the liquid bridge, and analyzes the causes of the liquid bridge; Finally, it analyzes the capillary adhesion phenomena on the performance of the micro-mechanical gyroscope,as well as how to avoid the generation of capillary condensation adhesion.

Abstract: As one of the new optical sensing devices, Resonant Micro-optic Gyro (RMOG) measures the rotation rate due to the resonance frequency difference based on the optical Sagnac effect. In order to reduce the influence of the light path and circuit noise and the output edge pulse signal, the mean filtering algorithm based on Labview is put forward to improve the gyros performance. The mean filtering algorithm is simulated and realized with Labview, which approves that the algorithm is effective in noise restraining. The test of RMOG demonstrates that the zero bias stability is 1.4 °/s during 1 hour with 10-second smoothing.

Abstract: A detailed analysis about the nonlinearity of a mode-matching MEMS vibratory gyroscope is presented in this paper, then closed loop control for the sense mode is adopted to improved the performances. Experimental results figure out that the mode-matching gyroscope with closed loop controlled sense mode achieves a scale factor of 65mV/deg/s with nonlinearity of 0.05% and asymmetry of 0.1%, and a bias instability of 0.77deg/h, while they are 60mV/deg/s, 1%, 4.6% and 9.8deg/h in the open loop controlled sense mode system, respectively. These performances can be improved by more than one order of magnitude in the closed loop control system.

Abstract: We demonstrated a novel approach for the interrogation of wavelength-modulated optical sensors. The interrogator is based on a tunable on-chip microring filter. By tuning the center wavelength of the microring filter, the center wavelength of the sensor can be readout by the corresponding tuning power. This approach has the potential of constructing a compact and cost-effective interrogator with good performance.

Abstract: The static bending model of microcantilever with monolayer molecules has been established based on energy method, in which the change in neutral layer position caused by adsorption-induced stress is introduced. On this basis, we have analyzed the relationship between the bending curvature radius of a microcantilever with its thickness, Young’s modulus and molecule-molecule distance of adsorbed molecules when it is adsorbed with monolayer water molecules. Additionally, we have investigated the effect of change in neutral layer position on the static behavior of microcantilever sensors. The results show that 1)the bending curvature radius of microcantilever is the linear, quadratic and eight approximation function of its Young’s modulus, thickness and distance of adsorbed molecules, respectively; 2)the predicted error of bending curvature radius caused by the change in neutral layer position slightly increases with decreasing Young’s modulus and thickness, whereas the effect of distance between adsorbed molecules on the error is significant; 3)the change in neutral layer position can cause a significant effect on the sensitivity and surface strain of the microcantilever