Spatial Thermal Gradient Mapping Micro-Machined Accelerometer Arrays
Spatial thermal gradient mapping in micro-machined accelerometer arrays decouples linear motion from external board heat using differential thermopile matrices.
MEMS Thermal Accelerometer
Inertial Transducer
Acceleration sensors utilize the properties of heat transfer in a gas to measure changes in motion. A mems thermal accelerometer replaces the traditional silicon beam and mass with a heated fluid bridge to eliminate mechanical fatigue. This construction provides a high degree of durability in high-shock environments.
Operating Principle
Central heating elements warm the surrounding air inside a tiny chamber. When motion occurs, the mems thermal accelerometer detects the shift of the heated air toward one of the surrounding thermopiles. This temperature difference generates a voltage signal.
Because no solid parts move, the device exhibits high shock resistance exceeding tens of thousands of gravities.
Performance Specification
Frequency response is limited by the thermal time constant of the gas. While a mems thermal accelerometer offers excellent stability at low frequencies, it cannot track high-frequency vibrations as effectively as a capacitive sensor. Bandwidth is usually restricted to below one hundred hertz for standard industrial applications.
Qualification Requirement
Power consumption is a primary factor during the component selection process. The heater in a mems thermal accelerometer requires a continuous current, which may drain batteries in remote sensing nodes. Qualification involves testing the stability of the heater resistance over thousands of hours of operation to ensure the calibration remains valid.