Multi-axis Response of a Thermal Convection-based Accelerometer

Abstract

A thermal convection-based accelerometer was fabricated, and its characteristics were analyzed in this study. To understand the thermal convection of the accelerometer, the Grashof and Prandtl number equations were analyzed. This study conducted experiments to improve not only the sensitivity, but also the frequency band. An accelerometer with a more voluminous cavity showed better sensitivity. In addition, when the accelerometer used a gas medium with a large density and small viscosity, its sensitivity also improved. On the other hand, the accelerometer with a narrow volume cavity that used a gas medium with a small density and large thermal diffusivity displayed a larger frequency band. In particular, this paper focused on a Z-axis response to extend the performance of the accelerometer.

Cantilever Type Acceleration Sensors Made by Roll-to-Roll Slot-Die Coating

“…They have been applied to the fields of automobile [ 1 , 5 ], healthcare [ 2 ], mobile devices [ 3 ], and electronic devices [ 4 ]. MEMS acceleration sensors are divided into capacitive [ 6 , 7 ], piezoelectric [ 8 , 9 ], piezoresistive [ 10 , 11 ], Hall effect [ 12 , 13 ], magnetoresistive [ 14 , 15 ] and heat transfer [ 16 , 17 ] types according to the sensing method used. The most common type of MEMS acceleration sensors are capacitive because of their simple structure, high productivity, linear stability, durability, and insensitivity to temperature [ 18 , 19 ].…”

Editorial for the Special Issue on MEMS Accelerometers

“…There are 16 papers published covering the design, fabrication, modeling and applications of MEMS accelerometers. Half of the papers discuss accelerometer integration [1,2], piezoresistive sensing [3,4] multi-axis accelerometers, and review current technologies [4,5,6]. Three papers investigate MEMS accelerometer multi-physics modeling [7,8,9,10].…”

“…X. Zhao et al [4] also develop a silicon-on-insulator (SOI) piezoresistive, three-axis acceleration sensor with demonstrated sensitivities along x-axis, y-axis, and z-axis of 0.255 mV/g, 0.131 mV/g, and 0.404 mV/g, respectively. A thermal convection-based accelerometer is fabricated and characterized by J. Kim et al [5]. They investigate the impact of cavity volume, gas medium density and viscosity with a focus on the Z-axis response.…”