Design Features of Sensitive Elements for Quartz and Silicon Pendulum Accelerometers

The article presents the review of the developed variants of pendulum accelerometers based on sensitive elements made of quartz and silicon (capacitive silicon and compensation quartz pendula) obtained by means of batch volume processing. The features of the technology for producing sensitive elements, in particular liquid etching of silicon and quartz, are given. The paper shows the analysis of the design and technological problems connected with the characteristics of the materials of production and process of the deep liquid anisotropic and isotrope etching. A special attention is given to the design features of torsional elements, because, in general, the output characteristics of the device depend on the production accuracy of such elements. Simulation of the deformation parameters and stiffness of the movable parts of the pendula was carried out in the SolidWorks Simulation program complex. The simulation results showed that it is possible to choose the necessary parameters of stiffness of the joint in a wide range by changing the geometry of the torsion bar. The best parameters for materials processing of the sensitive elements were determined. A distinctive feature of the developed technologies for producing sensitive elements of two types of accelerometers is their group character. A study of the produced samples carried out on the scanning electron microscope made it possible to determine the geometric parameters of the torsion bars of the sensitive elements. The stiffness of the structure and consequently the sensitivity of the accelerometer depended mainly on those parameters.