Summary:
UCLA researchers in the Department of Electrical and Computer Engineering have developed an accelerometer model that uses optomechanical transduction, enabling higher precision motion detection through a simplified design.
Background:
Modern transportation and communication technologies rely on the measurement and transduction of minute forces for position determination. Traditional technologies use capacitive or piezoresistive techniques that incorporate micro-electromechanical systems (MEMS) via integrated circuit technologies to convert accelerometer motion into an electric readout. The required circuit components are often complex, bulky, and costly, and suffer from increased noise and reduced sensitivity. Laser-based optomechanical transduction has emerged as a method of increasing device sensitivity. However, the practical implementation of optomechanical systems remains a challenge due to their complicated fabrication and limited dynamic range. There remains an unmet need for an affordable optomechanical device for inertial sensing.
Innovation:
UCLA researchers in the Department of Electrical and Computer Engineering have developed a novel optomechanical accelerometer system with an integrated optical feedback system. This accelerometer is comprised of an optical oscillator acting on a mechanical oscillator. The radiation pressure of an integrated laser drives the mechanical system into oscillation, allowing for significant improvements in measurement sensitivity and dynamic range. Minute changes in mechanical resonance are used to measure specific force. The photonic crystal integrated onto the silicon-on-insulator has been optimized for maximum radiation pressure generation by reducing electric field leakage. The researchers simulated and subsequently introduced a method to plot the effective mechanical frequency as a function of laser driving wavelength. As the intracavity power increases, the mechanical frequency predictably shifts, allowing for precision measurements.
Potential Applications:
• Precise navigation, attitude control and inertial measurements for targeting and trajectory control.
• Assessing the integrity and performance of buildings, dams, and bridges by detecting subtle vibrations, strains, and displacements.
• Detecting and measuring ground vibrations for improved seismic hazard assessment and disaster management.
• Inertial sensors for motion control and balancing, enabling robots to navigate complex environments and perform delicate tasks.
Advantages:
• Simplified design
• Reduced cost and size
• Increased sensitivity
• Extended dynamic range
Status of Development:
The inventors have designed, fabricated and tested this technology and have published a manuscript in an online journal.
Related Papers:
1. Huang, Yongjun, Jaime Gonzalo Flor Flores, Ying Li, Wenting Wang, Di Wang, Noam Goldberg, Jiangjun Zheng et al. "A Chip-Scale Oscillation-Mode Optomechanical Inertial Sensor Near the Thermodynamical Limits." Laser & Photonics Reviews 14, no. 5 (2020): 1800329.-US9897666B2, Chip-scale optomechanical magnetometerUS9239340B2, Optomechanical sensor for accelerometry and gyroscopy-US8867026B2, Chip-scale optomechanical gravimeter. https://arxiv.org/ftp/arxiv/papers/2003/2003.02767.pdf
2. Flores, Jaime Gonzalo Flor, Talha Yerebakan, Wenting Wang, Mingbin Yu, Dim-Lee Kwong, Andrey Matsko, and Chee Wei Wong. "Parametrically driven inertial sensing in chip-scale optomechanical cavities at the thermodynamical limits with extended dynamic range." arXiv preprint arXiv:2210.17014 (2022). https://onlinelibrary.wiley.com/doi/full/10.1002/lpor.202200827
Reference:
UCLA Case No. 2023-282
Lead Inventor:
Chee Wei Wong, UCLA Professor of Electrical and Computer Engineering