A MEMS piezoelectric solid disk gyroscope with improved sensitivity

Abstract

surface. This design deployed a bulk piezoelectric structure as an entire resonator without any other elastic structures, to increase the shock resistance, the energy conversion efficiency and decrease the fabrication complexity. However, the PZT material itself has the characteristic of low quality factor, low output signal and much mechanical noise, compared with the silica-based material. As a result, how to increase the output signal and the sensitivity is a hot topic for piezoelectric gyroscopes (Cheng et al. 2013).On the other hand, the development of the MEMS silicon vibrating gyroscopes shows that the mode matching is a valid solution to increase the output signal and sensitivity of the gyroscopes (Tanaka et al. 1995). The mode matching is to match the resonant frequency between the drive mode and the sense mode, and to eliminate the frequency split. In most of the vibrating gyroscopes, the exact calculation and design should be made to implement a good characteristic. The ring vibrating gyroscope is a kind of degenerate gyroscope (He and Najafi 2002), which has an inherent axial symmetric resonator and utilizes a degenerate vibration mode pair as the drive and sense modes to maximize the energy transfer between the two modes. The degenerate gyroscopes have an inherent mode matching, which improves the characteristic and increases the sensitivity of the devices. In recent years, more and more attentions have been attracted by the degenerate gyroscopes, including the ring vibrating gyroscopes (He and Najafi 2002; Najafi 2000, 2001) and the hemispherical resonator gyroscopes (Zotov et al. 2012;Pai et al. 2012;Cho et al. 2013).This paper proposes a novel disk-like solid piezoelectric gyroscope based on the in-plane bulk acoustic wave (BAW) resonance. This design combines the solid piezoelectric gyroscopes with a disk-like resonant structure which is inherently mode matched. The structure not only obtains the high shock resistance and energy conversion efficiency Abstract This paper introduces a MEMS piezoelectric solid disk gyroscope. The gyroscope operates in an inplane elliptic bulk acoustic wave mode with a frequency of 284 kHz. This gyroscope is an improvement of the solid piezoelectric gyroscope. A device, 6 mm in diameter, has been fabricated through the microelectromechanical systems process, and achieved a relatively high sensitivity and bias instability. In this paper, it is described that the design, fabrication, circuit system and characteristics of the piezoelectric solid disk gyroscope.

High-sensitivity tunneling magneto-resistive micro-gyroscope with immunity to external magnetic interference

“…An all-integrated nano-photonic optical gyroscope based on Sagnac effect is demonstrated to reduce thermal fluctuations and mismatch by exploiting the reciprocity of passive optical networks, increasing its sensitivity significantly 19 . A kind of MEMS piezoelectric solid disk gyroscope is proposed, which operates in an in-plane elliptic bulk acoustic wave (BAW) mode, and has an angular rate sensitivity of about 340 μV/°/s and remains linear with applied rotation rate as high as 500°/s 20 . In addition, a novel resonant square gyroscope based on a group of orthogonal degenerate modes can be efficiently transduced and operated using thin piezoelectric films, which show a linear rate sensitivity of 20.38 µV/°/s 21 .…”

“…However, the pursuit of MEMS gyroscopes based on new physical effects has never stopped [19][20][21][22][23][24] . An all-integrated nano-photonic optical gyroscope based on Sagnac effect is demonstrated to reduce thermal fluctuations and mismatch by exploiting the reciprocity of passive optical networks, increasing its sensitivity significantly 19 .…”

Concurrent Detection of Linear and Angular Motion using a Single-Mass 6-axis Piezoelectric IMU

“…The other structure is composed by a resonant slotted disk supported by a central cylindrical post and surrounded by capacitive electrodes used to force and sense vibration. The resonator disk has the advantages of providing high quality factor and thermal stability due to the low anchor 51 | P a g e www.ijacsa.thesai.org loss, air damping effect (perfored disk) and thermo-elastic dissipation [19]. Moreover, the symmetrical propriety of the disk structure offers a high sensitivity [17,20].…”

“…This configuration can improve performances due to the use of a great modal effective mass compared to other resonator designs [10,21]. The structure uses piezoelectric effect to drive and sense the 6-DOF (Degree of Freedom) which is an advantage compared to the tuning fork and disk resonator structures, which generally detects only angular motion components [17,19]. Moreover, the present design employs only four electrodes for driving the seismic mass and four other ones for separating the 6-DOF outputs.…”

Research on a Micro Piezoelectric Gyroscope with Concentrated Rocking‐Mass

“…Meanwhile, a solid structure without spring and cantilever beam is designed as the supporting body, deformable body, and energy body. As the PZT materials show higher values of effective transverse and longitudinal piezoelectric coefficients as compared to other piezoelectric materials such as ALN and quartz, they are for driving and sensing . The design is a good attempt to develop the PZT ceramics' application.…”