Limits...
Design and Analysis of a Novel Fully Decoupled Tri-axis Linear Vibratory Gyroscope with Matched Modes.

Xia D, Kong L, Gao H - Sensors (Basel) (2015)

Bottom Line: With the help of the finite element method (FEM) software ANSYS, the natural frequencies of drive, yaw, and pitch/roll modes are found to be 14,017 Hz, 14,018 Hz and 14,020 Hz, respectively.The cross-axis effect and scale factor of each mode are also simulated.All the simulation results are in good accordance with the theoretical analysis, which means the design is effective and worthy of further investigation on the integration of tri-axis accelerometers on the same single chip to form an inertial measurement unit.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Micro Inertial Instruments and Advanced Navigation Technology of the Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China. xiadz_1999@163.com.

ABSTRACT
We present in this paper a novel fully decoupled silicon micromachined tri-axis linear vibratory gyroscope. The proposed gyroscope structure is highly symmetrical and can be limited to an area of about 8.5 mm × 8.5 mm. It can differentially detect three axes' angular velocities at the same time. By elaborately arranging different beams, anchors and sensing frames, the drive and sense modes are fully decoupled from each other. Moreover, the quadrature error correction and frequency tuning functions are taken into consideration in the structure design for all the sense modes. Since there exists an unwanted in-plane rotational mode, theoretical analysis is implemented to eliminate it. To accelerate the mode matching process, the particle swam optimization (PSO) algorithm is adopted and a frequency split of 149 Hz is first achieved by this method. Then, after two steps of manual adjustment of the springs' dimensions, the frequency gap is further decreased to 3 Hz. With the help of the finite element method (FEM) software ANSYS, the natural frequencies of drive, yaw, and pitch/roll modes are found to be 14,017 Hz, 14,018 Hz and 14,020 Hz, respectively. The cross-axis effect and scale factor of each mode are also simulated. All the simulation results are in good accordance with the theoretical analysis, which means the design is effective and worthy of further investigation on the integration of tri-axis accelerometers on the same single chip to form an inertial measurement unit.

No MeSH data available.


Simplified models of drive-to-sense coupling effect: (a) Drive-to-pitch coupling effect; (b) Drive-to-yaw coupling effect.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4541915&req=5

sensors-15-16929-f010: Simplified models of drive-to-sense coupling effect: (a) Drive-to-pitch coupling effect; (b) Drive-to-yaw coupling effect.

Mentions: The drive-to-pitch/roll coupling effect can be simplified as the model shown in Figure 10a. In an ideal situation, the inner frame in pitch/roll mode has only 1-DOF in z-axis. However, the stiffness of spring-11 in y-axis is not infinite, which means that it is inevitable to deform in the drive direction by the force transformed from spring-3. Thus the sense frame will show an unwanted movement in y-axis, resulting in the coupling of drive mode to pitch/roll mode. Assuming that the outer frame in pitch/roll mode is driven to oscillate with an amplitude of yd in y-axis, the drive-to-pitch coupling displacement can be simply expressed as:(48)yd2p=F12k11y=4k3yd2k11y=2k3ydk11ywhere k11y is the stiffness of spring-11 in y-axis; F1 = 4k3yd is the drive force.


Design and Analysis of a Novel Fully Decoupled Tri-axis Linear Vibratory Gyroscope with Matched Modes.

Xia D, Kong L, Gao H - Sensors (Basel) (2015)

Simplified models of drive-to-sense coupling effect: (a) Drive-to-pitch coupling effect; (b) Drive-to-yaw coupling effect.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541915&req=5

sensors-15-16929-f010: Simplified models of drive-to-sense coupling effect: (a) Drive-to-pitch coupling effect; (b) Drive-to-yaw coupling effect.
Mentions: The drive-to-pitch/roll coupling effect can be simplified as the model shown in Figure 10a. In an ideal situation, the inner frame in pitch/roll mode has only 1-DOF in z-axis. However, the stiffness of spring-11 in y-axis is not infinite, which means that it is inevitable to deform in the drive direction by the force transformed from spring-3. Thus the sense frame will show an unwanted movement in y-axis, resulting in the coupling of drive mode to pitch/roll mode. Assuming that the outer frame in pitch/roll mode is driven to oscillate with an amplitude of yd in y-axis, the drive-to-pitch coupling displacement can be simply expressed as:(48)yd2p=F12k11y=4k3yd2k11y=2k3ydk11ywhere k11y is the stiffness of spring-11 in y-axis; F1 = 4k3yd is the drive force.

Bottom Line: With the help of the finite element method (FEM) software ANSYS, the natural frequencies of drive, yaw, and pitch/roll modes are found to be 14,017 Hz, 14,018 Hz and 14,020 Hz, respectively.The cross-axis effect and scale factor of each mode are also simulated.All the simulation results are in good accordance with the theoretical analysis, which means the design is effective and worthy of further investigation on the integration of tri-axis accelerometers on the same single chip to form an inertial measurement unit.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Micro Inertial Instruments and Advanced Navigation Technology of the Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China. xiadz_1999@163.com.

ABSTRACT
We present in this paper a novel fully decoupled silicon micromachined tri-axis linear vibratory gyroscope. The proposed gyroscope structure is highly symmetrical and can be limited to an area of about 8.5 mm × 8.5 mm. It can differentially detect three axes' angular velocities at the same time. By elaborately arranging different beams, anchors and sensing frames, the drive and sense modes are fully decoupled from each other. Moreover, the quadrature error correction and frequency tuning functions are taken into consideration in the structure design for all the sense modes. Since there exists an unwanted in-plane rotational mode, theoretical analysis is implemented to eliminate it. To accelerate the mode matching process, the particle swam optimization (PSO) algorithm is adopted and a frequency split of 149 Hz is first achieved by this method. Then, after two steps of manual adjustment of the springs' dimensions, the frequency gap is further decreased to 3 Hz. With the help of the finite element method (FEM) software ANSYS, the natural frequencies of drive, yaw, and pitch/roll modes are found to be 14,017 Hz, 14,018 Hz and 14,020 Hz, respectively. The cross-axis effect and scale factor of each mode are also simulated. All the simulation results are in good accordance with the theoretical analysis, which means the design is effective and worthy of further investigation on the integration of tri-axis accelerometers on the same single chip to form an inertial measurement unit.

No MeSH data available.