The μGro™: A Quartz MEMS Automotive Gyroscope

Madni, A.M.; Costlow, L.E.; Smith, Marc

doi:10.4271/2006-01-0143

Cited by 6 publications

(7 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Its mechanical structure consists of a double-ended tuning fork operated at or above 10 kHz with separate drive and sensing tines optimized for their respective drive and sense functions, utilizing piezoelectric actuation and detection. Masses on the [2] tine ends are laser trimmed to automatically adjust resonant frequencies and quadrature error [4].…”

Section: B Commercial Mems Automotive Gyroscopesmentioning

confidence: 99%

“…The equation of motion of the 1-DOF sense-mode oscillator is 3where is the portion of the driven proof mass that contributes to the Coriolis force, and is the portion of the proof mass that responds to the Coriolis force. Defining the sensemode resonant frequency and quality factor ( factor) , amplitude of the steady-state Coriolis response becomes (4) where 5To achieve the maximum possible gain in the sense mode, it is generally desired to operate at or near the peak of the sense-mode response curve. This is typically achieved by matching drive and sense resonant frequencies.…”

Section: Fundamental Challengesmentioning

confidence: 99%

“…It consists of two identical multi-DOF systems, labeled left mass and right mass, connected via a coupling suspension forming a 2-DOF dynamic system in the drive mode. These systems are equivalent to the tines of a tuning fork; the major difference between conventional tuning fork gyroscopes [4], [8], however, is that both tines are multi-DOF devices, which contain decoupled 2-DOF sense modes. The frequency response of an ideal multi-DOF tine is identical to the regular multi-DOF gyroscope, Fig.…”

Section: A Design Conceptmentioning

confidence: 99%

See 2 more Smart Citations

Environmentally Robust MEMS Vibratory Gyroscopes for Automotive Applications

Acar¹,

et al. 2009

Self Cite

View full text Add to dashboard Cite

Automotive applications are known to impose quite harsh environmental conditions such as vibration, shock, temperature, and thermal cycling on inertial sensors. Micromachined gyroscopes are known to be especially challenging to develop and commercialize due to high sensitivity of their dynamic response to fabrication and environmental variations. Meeting performance specifications in the demanding automotive environment with low-cost and high-yield devices requires a very robust microelectromechanical systems (MEMS) sensing element. This paper reviews the design trend in structural implementations that provides inherent robustness against structural and environmental parameter variations at the sensing element level. The fundamental approach is based on obtaining a gain and phase stable region in the frequency response of the sense-mode dynamical system in order to achieve overall system robustness. Operating in the stable sense frequency region provides improved bias stability, temperature stability, and immunity to environmental and fabrication variations.

show abstract

Section: B Commercial Mems Automotive Gyroscopesmentioning

confidence: 99%

Section: Fundamental Challengesmentioning

confidence: 99%

Section: A Design Conceptmentioning

confidence: 99%

See 1 more Smart Citation

Environmentally Robust MEMS Vibratory Gyroscopes for Automotive Applications

Acar¹,

et al. 2009

Self Cite

View full text Add to dashboard Cite

show abstract

“…Large inertial mass can improve gyroscopes’ performance efficiently [ 8 , 9 , 11 , 16 ]. In order to enlarge inertial mass, a pair of proof masses is attached to the ends of the drive beam.…”

Section: Design Conceptmentioning

confidence: 99%

A Z-axis Quartz Cross-fork Micromachined Gyroscope Based on Shear Stress Detection

Xie

et al. 2010

Sensors

View full text Add to dashboard Cite

Here we propose a novel quartz micromachined gyroscope. The sensor has a simple cross-fork structure in the x-y plane of quartz crystal. Shear stress rather than normal stress is utilized to sense Coriolis’ force generated by the input angular rate signal. Compared to traditional quartz gyroscopes, which have two separate sense electrodes on each sidewall, there is only one electrode on each sidewall of the sense beam. As a result, the fabrication of the electrodes is simplified and the structure can be easily miniaturized. In order to increase sensitivity, a pair of proof masses is attached to the ends of the drive beam, and the sense beam has a tapered design. The structure is etched from a z-cut quartz wafer and the electrodes are realized by direct evaporation using the aperture mask method. The drive mode frequency of the prototype is 13.38 kHz, and the quality factor is approximately 1,000 in air. Therefore, the gyroscope can work properly without a vacuum package. The measurement ability of the shear stress detection design scheme is validated by the Coriolis’ force test. The performance of the sensor is characterized on a precision rate table using a specially designed readout circuit. The experimentally obtained scale factor is 1.45 mV/°/s and the nonlinearity is 3.6% in range of ±200 °/s.

show abstract

“…[1][2][3] For its excellent piezoelectric effect and mechanical behaviour, quartz has become an important material in the micromachined gyroscope field. 4 Therefore, a novel z-axis quartz micromachined gyroscope is proposed in our previous work and shown in Fig. 1.…”

Section: Introductionmentioning

confidence: 99%

Fabrication of a novel quartz micromachined gyroscope

et al. 2015

View full text Add to dashboard Cite

A novel quartz micromachined gyroscope is proposed in this paper. The novel gyroscope is realized by quartz anisotropic wet etching and 3-dimensional electrodes deposition. In the quartz wet etching process, the quality of Cr/Au mask films affecting the process are studied by experiment. An excellent mask film with 100 Å Cr and 2000 Å Au is achieved by optimization of experimental parameters. Crystal facets after etching seriously affect the following sidewall electrodes deposition process and the structure’s mechanical behaviours. Removal of crystal facets is successfully implemented by increasing etching time based on etching rate ratios between facets and crystal planes. In the electrodes deposition process, an aperture mask evaporation method is employed to prepare electrodes on 3-dimensional surfaces of the gyroscope structure. The alignments among the aperture masks are realized by the ABM™ Mask Aligner System. Based on the processes described above, a z–axis quartz gyroscope is fabricated successfully.

show abstract

The ^μGro^™: A Quartz MEMS Automotive Gyroscope

Cited by 6 publications

References 1 publication

Environmentally Robust MEMS Vibratory Gyroscopes for Automotive Applications

Environmentally Robust MEMS Vibratory Gyroscopes for Automotive Applications

A Z-axis Quartz Cross-fork Micromachined Gyroscope Based on Shear Stress Detection

Fabrication of a novel quartz micromachined gyroscope

Contact Info

Product

Resources

About