Patents by Inventor Tijing CAI

Tijing CAI has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11914100
    Abstract: The present invention discloses a method for determining an inverse of gravity correlation time. During data processing on gravity measurement of moving bases, a gravity anomaly is considered as a stationary random process in a time domain, and is described with a second-order Gauss Markov model, a third-order Gauss Markov model or an mth-order Gauss Markov model, and the inverse of gravity correlation time is an important parameter of the gravity-anomaly model, and according to a gravity sensor root mean square error, a Global Navigation Satellite System (GNSS) height root mean square error, an a priori gravity root mean square, and a gravity filter cutoff frequency during the gravity measurement of the moving bases, an inverse of gravity correlation time of the second-order, third-order or mth-order Gauss Markov model is determined.
    Type: Grant
    Filed: June 4, 2020
    Date of Patent: February 27, 2024
    Assignee: SOUTHEAST UNIVERSITY
    Inventor: Tijing Cai
  • Patent number: 11372130
    Abstract: Disclosed is a calibration method for a rotating accelerometer gravity gradiometer, wherein linear motion error coefficients, angular motion error coefficients, self-gradient model parameters and scale factors of the rotating accelerometer gravity gradiometer are calibrated once by changing linear motion, angular motion, and self-gradient excitations of the rotating accelerometer gravity gradiometer. The calibrated linear and angular motion error coefficients are used for compensating for motion errors of the gravity gradiometer online, and the calibrated self-gradient model parameters are used for self-gradient compensation. The calibration method provided by the present invention is easy to operate and not limited by any calibration site, thereby being suitable for programmed self-calibration and realizing an important engineering value.
    Type: Grant
    Filed: May 30, 2019
    Date of Patent: June 28, 2022
    Assignee: SOUTHEAST UNIVERSITY
    Inventors: Tijing Cai, Mingbiao Yu
  • Patent number: 11372129
    Abstract: A post-compensation method for motion errors of a rotating accelerometer gravity gradiometer includes the steps of: during moving-base gravity gradient exploration, recording angular and linear motions of a gravity gradiometer; after the exploration, removing angular and linear motion errors from output data of the gravity gradiometer based on an analytical model of the rotating accelerometer gravity gradiometer; while ensuring that the precision of the gravity gradiometer is unchanged, the post-compensation method for the motion errors may be applied to greatly reduce the requirements of the gravity gradiometer for the precision of an online error compensation system, thereby simplifying the circuit design and mechanical design of the rotary accelerometer gravity gradiometer, and making the rotating accelerometer gravity gradiometer simpler and cheaper.
    Type: Grant
    Filed: May 30, 2019
    Date of Patent: June 28, 2022
    Assignee: SOUTHEAST UNIVERSITY
    Inventors: Tijing Cai, Mingbiao Yu
  • Publication number: 20220120932
    Abstract: The present invention discloses a method for determining an inverse of gravity correlation time. During data processing on gravity measurement of moving bases, a gravity anomaly is considered as a stationary random process in a time domain, and is described with a second-order Gauss Markov model, a third-order Gauss Markov model or an mth-order Gauss Markov model, and the inverse of gravity correlation time is an important parameter of the gravity-anomaly model, and according to a gravity sensor root mean square error, a Global Navigation Satellite System (GNSS) height root mean square error, an a priori gravity root mean square, and a gravity filter cutoff frequency during the gravity measurement of the moving bases, an inverse of gravity correlation time of the second-order, third-order or mth-order Gauss Markov model is determined.
    Type: Application
    Filed: June 4, 2020
    Publication date: April 21, 2022
    Inventor: Tijing CAI
  • Publication number: 20220091299
    Abstract: Disclosed is a calibration method for a rotating accelerometer gravity gradiometer, wherein linear motion error coefficients, angular motion error coefficients, self-gradient model parameters and scale factors of the rotating accelerometer gravity gradiometer are calibrated once by changing linear motion, angular motion, and self-gradient excitations of the rotating accelerometer gravity gradiometer. The calibrated linear and angular motion error coefficients are used for compensating for motion errors of the gravity gradiometer online, and the calibrated self-gradient model parameters are used for self-gradient compensation. The calibration method provided by the present invention is easy to operate and not limited by any calibration site, thereby being suitable for programmed self-calibration and realizing an important engineering value.
    Type: Application
    Filed: May 30, 2019
    Publication date: March 24, 2022
    Applicant: SOUTHEAST UNIVERSITY
    Inventors: Tijing CAI, Mingbiao YU
  • Publication number: 20220075091
    Abstract: A post-compensation method for motion errors of a rotating accelerometer gravity gradiometer includes the steps of: during moving-base gravity gradient exploration, recording angular and linear motions of a gravity gradiometer; after the exploration, removing angular and linear motion errors from output data of the gravity gradiometer based on an analytical model of the rotating accelerometer gravity gradiometer; while ensuring that the precision of the gravity gradiometer is unchanged, the post-compensation method for the motion errors may be applied to greatly reduce the requirements of the gravity gradiometer for the precision of an online error compensation system, thereby simplifying the circuit design and mechanical design of the rotary accelerometer gravity gradiometer, and making the rotating accelerometer gravity gradiometer simpler and cheaper.
    Type: Application
    Filed: May 30, 2019
    Publication date: March 10, 2022
    Applicant: SOUTHEAST UNIVERSITY
    Inventors: Tijing CAI, Mingbiao YU