Study On Key Technologies Of A Novel Butterfly Accelerometer

In all the kinds of accelerometers,torsional accelerometers are the most widely used for their simple design and low cost.However,torsional accelerometers still have some disadvantages in the stability and temperature drift performance,limiting their application.Aiming to solve the problems in traditional torsional accelerometers,this paper propose a novel butterfly accelerometers with simply fabrication process,high sensitivity,high robustness and good temperature drift performance.In this paper,the structure design,fabrication process,readout circuit,testing table and testing results are introduced while the detailed works are shown as following:1.Design model and working principle are proposed.In this section,static analysis for the hexagonal torsional beam and capacitive sensitivity of the structure are taken firstly,and then the structure geometry are decided based on the static analysis and the preferred parameters.Then,finite element(FE)simulation of the capacitive sensitivity and nonlinearity for the model is taken using ANSYS,demonstrating validity of the static analysis.And moreover,the temperature drift performance of both the traditional torsional accelerometers and the proposed butterfly accelerometer are simulated,showing that the butterfly accelerometer design can effectively improve the temperature drift performance.2.Fabrication process is introduced.Prototypes are fabricated using a pre-buried mask wet-etching method and basic performance tests are taken on the dies to screen out the available ones.Then,the dies are attached to a ceramic package using eutectic solder,and then wire bonded.3.Readout circuit is designed and analyzed.Several kinds of readout circuits are investigated and compared,and based on requirement of the proposed butterfly accelerometer,reversely symmetry exciting circuit is used in this paper.Moreover,the automatic testing table is realized based on the LabVIEW software,making the performance testing more simple and efficient.At last of this paper,the testing results for the butterfly accelerometer are shown.It shows that the starting time,stability in an hour,temperature sensitivity of the scale factor,nonlinearity in the full range and bandwidth of the novel accelerometer are ten minutes,0.39 mg,135.449ppm/?,0.3% and 59.09 Hz separately,demonstrating that butterfly accelerometer has a good performance and satisfies the preferred parameters.