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dc.contributor.advisorSideris, Michael
dc.contributor.authorMokhtari, Elaheh
dc.date.accessioned2015-09-24T20:16:03Z
dc.date.issued2015-09-24
dc.date.submitted2015en
dc.identifier.citationMokhtari, E. (2015). Sensor Error Analysis of Superconductive Angular Gradiometer (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/27755en_US
dc.identifier.urihttp://hdl.handle.net/11023/2493
dc.description.abstractA superconductive angular gradiometer is a pair of superconductive angular accelerometers that pivot about a common axis. The output of the sensor corresponds to gradients. The gradients are effective not only in explorations of ore bodies and oil fields, but also in a complete modeling of the gravity field of the Earth. The superconductive angular gradiometer typically carries by a mobile platform to collect the measurements. Therefore, the instrument senses not only gravity gradients, but also various effects of an accelerated coordinate frame (introducing errors). The errors in the gradiometer channel are technically removed through some electrical, mechanical, and empirical approaches. A major effort in this study is given to an efficient and a cost effective post processing approach to deal with only the effect of angular velocities squared. A superconductive angular accelerometer is an important sensor that often supplements a mobile superconductive angular gradiometer during data acquisition operations. While the angular accelerations are measured, the angular velocities squared are computed by integration. However, the angular accelerations are noisy because of translational accelerations of the platform and temperature fluctuations of the environment during the operation. Wavelet de-noising and de-trending techniques have been implemented in order to mitigate these errors. The results indicate that more than 66% of the noise level was efficiently reduced in comparison to the empirical approach by the company for the static x angular accelerations. This improvement was achieved without knowledge of the temperature and other error effects. Furthermore, the effect of angular velocities squared, which is about -20 Eötvös, is removed from the gradiometer output. Then, the performance of the gradiometer is evaluated through a simulation study by error propagation in a single-input-single-output system. The standard deviations of the static x angular acceleration, y angular acceleration, and differential mode after the wavelet analysis are 3.08e-05 rad/s2, 3.55e-05 rad/s2, and 3.21e-08 rad/s2, respectively. So, the the final accuracy of the true gradient in this research work is 0.06 Eötvös, which makes the system suitable for variety exploration applications that require the gradients to be known with an accuracy of 1 Eötvös or better.en_US
dc.language.isoeng
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectGeodesy
dc.subject.classificationSuperconductiveen_US
dc.subject.classificationAngular Gradiometeren_US
dc.titleSensor Error Analysis of Superconductive Angular Gradiometer
dc.typedoctoral thesis
dc.publisher.facultyGraduate Studies
dc.description.embargoterms2 yearsen_US
dc.date.embargolift2017-09-23T20:16:03Z
dc.publisher.institutionUniversity of Calgaryen
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/27755
thesis.degree.nameDoctor of Philosophy
thesis.degree.namePhD
thesis.degree.disciplineGeomatics Engineering
thesis.degree.grantorUniversity of Calgary
atmire.migration.oldid3608
dc.publisher.placeCalgaryen


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