{"title":"Highly Accurate Inertial Navigation that Compensates for the Earth's Rotation and Sensor BIAS Using Non-Holonomic Constraints","authors":"Masato Kimishima, T. Sawada, Akihiro Sonoura, Toru Amano, Hiroyuki Kamata, Kosei Yamashita","doi":"10.1109/INERTIAL56358.2023.10103969","DOIUrl":"https://doi.org/10.1109/INERTIAL56358.2023.10103969","url":null,"abstract":"This proposal presents a means of increasing the accuracy of inertial navigation (IN) by isolating the Earth's rotation and sensor bias. It is designed as a means of navigation for moving objects using just an IMU without any external sensors. By eliminating the Earth's rotation, which is a factor that leads to IN errors, even with online processing during movement, IN measurement errors were reduced from approximately 20 m every 60 seconds to just 2 m. In order to isolate the angular velocity of the Earth from the angular velocity of a moving object, we focused on non-holonomic constraints (NHC) and optimized the index of precision to minimize velocity errors, allowing us to successfully isolate the Earth's rotation and separate it from gyroscope bias during motion. As a result, the conventional “maytagging” method, whereby complex calibrations are carried out on the stationary object before movement, is rendered unnecessary.","PeriodicalId":236326,"journal":{"name":"2023 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125146752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Danmeng Wang, Nicholas A. Strnad, Yusheng Wang, Austin R. Parrish, R. Benoit, R. Knight, A. Shkel
{"title":"Indirect Excitation of micro-HRG Using Segmented Piezoelectric ALD PHT Actuator","authors":"Danmeng Wang, Nicholas A. Strnad, Yusheng Wang, Austin R. Parrish, R. Benoit, R. Knight, A. Shkel","doi":"10.1109/INERTIAL56358.2023.10103950","DOIUrl":"https://doi.org/10.1109/INERTIAL56358.2023.10103950","url":null,"abstract":"This paper presents, for the first time, an indirect excitation method for three-dimensional fused quartz dual-shell micro-scale Hemispherical Resonator Gyroscope μHRG. The μHRG was fabricated using three wafer bonding and high-temperature micro-glassblowing processes, providing a sensing element (device shell), a self-aligned fixed-fixed anchor for increased immunity to mechanical shocks and vibrations, and a housing (cap shell) for vacuum encapsulation. The novel actuation technique uses piezoelectric actuation to transfer energy from the cap shell to the device shell to excite the resonant element, where the piezoelectric material is deposited and shaped on the outer cap shell. Using the proposed indirect excitation method, the metal coating of the device shell is eliminated, preserving the high quality factor of the pristine fused quartz material. In this paper, we first introduce the mechanism of excitation, supported by Finite Element Analysis (FEA). We then describe the Atomic Layer Deposition (ALD) method of PbHf˟Ti1-˟O3 (PHT) piezoelectric material, followed by the fabrication process of a dual-shell μHRG prototype co-fabricated with an 80 nm layer of ALD PHT actuator. Finally, we experimentally demonstrated the indirect excitation, showing the feasibility of the method as a possible alternative to capacitive or direct piezoelectric actuation. Though early in development, the reported excitation approach may offer a preferable method for excitation of μHRGs, allowing to achieve the ultra-high mechanical quality factor, on the level of the TED-limit of fused quartz.","PeriodicalId":236326,"journal":{"name":"2023 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114325881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Schiwietz, Laukik R. More, E. Weig, Peter Degenfeld-Schonburg
{"title":"Simulation of Anchor Loss in MEMS Resonators Using Perfectly Matched Layers","authors":"Daniel Schiwietz, Laukik R. More, E. Weig, Peter Degenfeld-Schonburg","doi":"10.1109/INERTIAL56358.2023.10103970","DOIUrl":"https://doi.org/10.1109/INERTIAL56358.2023.10103970","url":null,"abstract":"Recently, it has been shown that there is a significant pressure and temperature independent damping contribution for high-frequency modes in commercial MEMS gyroscopes. In order to investigate the contribution of anchor losses to the observed damping, perfectly matched layer (PML) simulations can be employed. This work serves as a preparatory step towards the simulation of anchor losses in complex MEMS gyroscopes. We focus on simple geometries, in order to infer general modelling rules for the setup of PML simulations. Therefore, we simulate a cantilever beam and verfiy the simulations with existing analytic results. We demonstrate a systematic approach to set up anchor loss models of MEMS resonators, which yields reliable results for various mode shapes. Furthermore, we simulate two coupled cantilever beams and show that degenerate modes, only differing in symmetries, have significantly different anchor loss quality factors. The insights gained from these simple geometries will be applied to the simulation of complex MEMS gyroscopes in the future.","PeriodicalId":236326,"journal":{"name":"2023 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL)","volume":"34 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125720210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}