A triaxial high-g accelerometer of microelectro mechanical systems （MEMS） has a struc- ture of multi-chips combination and will be used in aerospace field, civil and military fields. The ac- celerometer can measure ...A triaxial high-g accelerometer of microelectro mechanical systems （MEMS） has a struc- ture of multi-chips combination and will be used in aerospace field, civil and military fields. The ac- celerometer can measure the acceleration of the carrier. The chips with island-membrane structures on its back surfaces are made by MEMS dry processing. The chip is reasonable and can work well under high impact load; Titanium alloy base is also stronger in high shock environment, these are proved by finite element analysis. Finally, the MEMS combined triaxial high-g accelerometer is vali- dated by high impact calibration experiments in order to get a key performance index, including range, sensitivity and transverse sensitivity and so on. These data can satisfy the need of design but some problems remain, these will be eliminated by improvement of the processing technology and materials.展开更多
The behavior of resistance high-g impact of EMC （epoxy molding compound） with two package models, small outline package （POS） and Globtop, was evaluated by experimental method used Hopkinson bar. At 120,000 g （ge...The behavior of resistance high-g impact of EMC （epoxy molding compound） with two package models, small outline package （POS） and Globtop, was evaluated by experimental method used Hopkinson bar. At 120,000 g （generated in the Hopkinson bar with widths about 70 μs） no damage in either the POS devices or the Globtop devices was observed. In order to enhance the EMC＇s ability of resistance high-g impact, buffering effect of epoxy resin was also studied. The experimental results above all show that EMC has a better performance of impact resistance at about 120,000 g, and epoxy resin can absorb the stress wave to have the protected ability. The study of this paper could serve as a basis for selection packaging materials and enhance its reliability in high-g impact environment.展开更多
A high-g beam-mass structure accelerometer was designed.In this structure,by means of KOH back etching on the mass,V-groove structure was fabricated on the backside of the mass,so the weight of the mass and also the r...A high-g beam-mass structure accelerometer was designed.In this structure,by means of KOH back etching on the mass,V-groove structure was fabricated on the backside of the mass,so the weight of the mass and also the relative distance between the mass center and the neutral plane were all decreased.With the thin mass structure,we can take advantage of both beam-mass structure and flat film structure;the fabrication process is also simple.By means of Hopkinson shock test system,we did the accelerometer calibration.According to the test result,the sensitivity of the MEMS accelerometer is 0.71 μV/g,which keeps in accordance with the theoretical calculation.After a 200 000 g shocking test,the micro structure worked as usual,so this design can satisfy the requirements of high shock,seriously vibration test environment.展开更多
In this study, the discharge voltage behavior of electric double-layer capacitors （EDLCs） during high-g impact is studied both theoretically and experimentally. A micro-scale dynamic mechanism is proposed to describ...In this study, the discharge voltage behavior of electric double-layer capacitors （EDLCs） during high-g impact is studied both theoretically and experimentally. A micro-scale dynamic mechanism is proposed to describe the physical basis of the increase in the discharge voltage during a high-g impact. Based on this dynamic mechanism, a multi-field model is established, and the simulation and experimental studies of the discharge voltage increase phenomenon are conducted. From the simulation and experimental data, the relationship between the increased voltage and the high-g acceleration is revealed. An acceleration detection range of up to 10,000g is verified. The design of the device is optimized by studying the influences of the parameters, such as the electrode thickness and discharge current, on the outputs. This work opens up new avenues for the development of autonomous sensor systems based on energy storage devices and is significant for many practical applications such as in collision testing and automobile safety.展开更多
基金Supported by the National Natural Science Foundation of China(61273346)the National Defense Major Fundamental Research Program of China(20110003)+3 种基金the National Defense Key Fundamental Research Program of China(20132010)Specialized Research Fund for the Doctoral Program of Higher Education(20121101120009)Excellent Young Scholars Research Fund of Beijing Institute of Technology(2012YG0203)the Program for the Fundamental Research of Beijing Institute of Technology(2015CX02034)
文摘A triaxial high-g accelerometer of microelectro mechanical systems （MEMS） has a struc- ture of multi-chips combination and will be used in aerospace field, civil and military fields. The ac- celerometer can measure the acceleration of the carrier. The chips with island-membrane structures on its back surfaces are made by MEMS dry processing. The chip is reasonable and can work well under high impact load; Titanium alloy base is also stronger in high shock environment, these are proved by finite element analysis. Finally, the MEMS combined triaxial high-g accelerometer is vali- dated by high impact calibration experiments in order to get a key performance index, including range, sensitivity and transverse sensitivity and so on. These data can satisfy the need of design but some problems remain, these will be eliminated by improvement of the processing technology and materials.
基金Funded by the State Key Laboratory Foundation of China (No.9140C120704060C12)the Science and Technology Development Project of Universiti-esin of Shanxi Province
文摘The behavior of resistance high-g impact of EMC （epoxy molding compound） with two package models, small outline package （POS） and Globtop, was evaluated by experimental method used Hopkinson bar. At 120,000 g （generated in the Hopkinson bar with widths about 70 μs） no damage in either the POS devices or the Globtop devices was observed. In order to enhance the EMC＇s ability of resistance high-g impact, buffering effect of epoxy resin was also studied. The experimental results above all show that EMC has a better performance of impact resistance at about 120,000 g, and epoxy resin can absorb the stress wave to have the protected ability. The study of this paper could serve as a basis for selection packaging materials and enhance its reliability in high-g impact environment.
基金Shanxi province young leaders on science and by program for New Century Excellent Talents in University(NCET)
文摘A high-g beam-mass structure accelerometer was designed.In this structure,by means of KOH back etching on the mass,V-groove structure was fabricated on the backside of the mass,so the weight of the mass and also the relative distance between the mass center and the neutral plane were all decreased.With the thin mass structure,we can take advantage of both beam-mass structure and flat film structure;the fabrication process is also simple.By means of Hopkinson shock test system,we did the accelerometer calibration.According to the test result,the sensitivity of the MEMS accelerometer is 0.71 μV/g,which keeps in accordance with the theoretical calculation.After a 200 000 g shocking test,the micro structure worked as usual,so this design can satisfy the requirements of high shock,seriously vibration test environment.
文摘In this study, the discharge voltage behavior of electric double-layer capacitors （EDLCs） during high-g impact is studied both theoretically and experimentally. A micro-scale dynamic mechanism is proposed to describe the physical basis of the increase in the discharge voltage during a high-g impact. Based on this dynamic mechanism, a multi-field model is established, and the simulation and experimental studies of the discharge voltage increase phenomenon are conducted. From the simulation and experimental data, the relationship between the increased voltage and the high-g acceleration is revealed. An acceleration detection range of up to 10,000g is verified. The design of the device is optimized by studying the influences of the parameters, such as the electrode thickness and discharge current, on the outputs. This work opens up new avenues for the development of autonomous sensor systems based on energy storage devices and is significant for many practical applications such as in collision testing and automobile safety.
