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MEMS accelerometer embedded in a self-mixing displacement sensor for parasitic vibration compensation
Usman Zabit1, Olivier D Bernal, Thierry Bosch
1CNRS, LAAS, Toulouse, France. usman.zabit@enseeiht.fr
Optics Letters
|March 4, 2011
Summary
This study introduces a self-mixing laser displacement sensor combined with a MEMS accelerometer for accurate measurements, even with a moving laser head. Improved resolution is achievable with a low-noise accelerometer.
Area of Science:
- Optoelectronics
- Microelectromechanical Systems (MEMS)
- Sensor Technology
Background:
- Self-mixing (SM) laser sensors offer precise displacement measurement capabilities.
- Nonstationary laser heads pose challenges for traditional SM sensor accuracy.
- MEMS accelerometers can provide motion compensation data for sensors.
Purpose of the Study:
- To develop a robust self-mixing laser displacement sensor system.
- To enable reliable displacement measurements with a nonstationary laser head.
- To explore the integration of MEMS accelerometers for enhanced sensor performance.
Main Methods:
- Coupling a self-mixing laser displacement sensor with a MEMS accelerometer.
- Utilizing accelerometer data to compensate for laser head movement.
- Analyzing system resolution limitations and potential improvements.
Main Results:
- Demonstrated reliable displacement measurements despite laser head nonstationarity.
- Achieved a system resolution of approximately 300 nm with the current MEMS accelerometer.
- Identified accelerometer noise as the primary limitation for higher resolution.
Conclusions:
- The integrated SM laser and MEMS accelerometer system is suitable for embedded applications.
- System resolution can be significantly enhanced by employing low-noise accelerometers.
- This approach broadens the applicability of SM sensors in dynamic environments.
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