Tilt Sensor with Recalibration Feature Based on MEMS Accelerometer

Area of Science:

• Sensor Technology
• Mechanical Engineering
• Metrology

Background:

• Micro-electro-mechanical systems (MEMS) accelerometers suffer from significant errors including axis misalignment, thermal/long-term drifts, calibration inaccuracies, and aging.
• These errors limit the precision and reliability of MEMS accelerometers in tilt sensing applications.

Purpose of the Study:

• To develop and evaluate a two-axial tilt sensor designed to mitigate common MEMS accelerometer errors.
• To improve the accuracy and stability of tilt measurements through precise alignment and recalibration capabilities.

Main Methods:

• Construction of a two-axial tilt sensor incorporating a triaxial MEMS accelerometer, an aligning unit, and a solid cubic housing.
• Utilizing the aligning unit to achieve precise orientation alignment of accelerometer sensitive axes relative to the housing (0.03° accuracy).
• Implementing a recalibration procedure facilitated by the housing to eliminate drift and aging effects.

Main Results:

• Achieved precise alignment of accelerometer sensitive axes with 0.03° accuracy relative to the housing.
• Successfully eliminated errors from thermal and long-term drifts, and aging phenomena through recalibration.
• Demonstrated compensation for local and temporal variations in gravitational acceleration.
• Presented tilt errors as high as 0.4° due to thermal and long-term drifts in the tested sensor.

Conclusions:

• The developed two-axial tilt sensor effectively reduces MEMS accelerometer errors, enhancing measurement accuracy and reliability.
• The sensor's design allows for easy and rapid recalibration, compensating for environmental and aging effects.
• The sensor shows potential for applications in monitoring elevated loads and other precision tilt measurement tasks.