چكيده به لاتين
Nowadays, the need for more accurate measuring instruments in different fields - industry, medicine, agriculture, aerospace, and so on - is strongly felt. Regarding this, the progress in microchip (ICs) manufacturing technology has brought about the emergence of microelectromechanical systems (MEMS) technology with high functional accuracy and the possibility of constructing a class of structures, systems, and mechanical systems in micron dimensions, it has in return led to their widespread use in a wide range of applications, like the aerospace industry, the automotive industry, medical devices, and the electronics consumer market. MEMS accelerometers are of the most commonly used sensors in devices like smartphones, computers and wearable electronics technologies, as well as in vehicle health monitoring systems, missile guidance and navigation, and launchers, jet engines, and power plants. The uses of the accelerometer in space are affected by several factors because of functional, environmental and instrumental needs. Measuring acceleration at various g scales, determining speed and position related to navigation performance calls for the highest accuracy among accelerometer uses.
In this research, while developing an operational algorithm for designing MEMS, we tried to design and optimize an applied accelerometer for the space industry to control the active equilibrium state with acceleration characteristics of ±100 g and a resolution of 1 mg resolution according to the developed algorithm. The process of structure designing this accelerometer is done according to construction needs and constraints in Iran and is based on volumetric micro-machining manufacturing technology. One of the optimization features done throughout designing is the extraction of a ratio of 2.67 for gap-to-anti-gap ratio, increasing the capacitance sensitivity by 30%. In this study, using the I-shaped structure for the suspended mass structure and optimizing the dimensions of the flange and its bulking, while using the maximum suspended structure mass - reducing systemic noise - the system sensitivity was optimized in proportion to the vertical bending of the structure so that the vertical bending of the structure is reduced by up to 50% for a certain mass of the suspended and longitudinal dimensions. Ultimately, by developing the prototype and structurally proposed symmetrically and bilaterally integrated by the bridge, we could benefit from the transverse space of the system to obtain an accelerometer with a range of ±100 g and a sensitivity of 0.43 fF/g. The voltage and capacitance sensitivity of the sensor output has increased by 27% and 139%, respectively in this design compared to the original design.
