Patents by Inventor Zhaoxiang WU

Zhaoxiang WU 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).

  • Method for correcting pointing errors of biaxial rotation system based on spherical cap function
    Patent number: 12265407
    Abstract: The invention discloses a method for correcting the pointing errors of a biaxial rotation system based on the spherical cap function, comprising: error collection: selecting stars or radio sources distributed evenly in a star catalogue for tracking and observation to obtain the theoretical position and measurement position of the stars, and subtracting the measurement positions and the theoretical positions to obtain the error distribution; error model fitting: selecting a suitable orthogonal spherical cap function for the obtained error distribution and performing fitting to calculate an error fitting coefficient, the orthogonal spherical cap function model comprising a hemispheric harmonic function HSH, a Zernike spherical cap function ZSF, and a longitudinal spherical cap function LSF; and error control and compensation: putting the error model and the related fitting coefficient into a pointing control system for compensation.
    Type: Grant
    Filed: September 14, 2020
    Date of Patent: April 1, 2025
    Assignee: NANJING INSTITUTE OF ASTRONOMICAL OPTICS & TECHNOLOGY, NATIONAL ASTRONOMICAL OBSERVATORIES, CAS
    Inventors: Yi Zheng, ying Li, Zhaoxiang Wu, Bin Liang, Lifeng Tang
  • METHOD FOR CORRECTING POINTING ERRORS OF BIAXIAL ROTATION SYSTEM BASED ON SPHERICAL CAP FUNCTION
    Publication number: 20220404844
    Abstract: The invention discloses a method for correcting the pointing errors of a biaxial rotation system based on the spherical cap function, comprising: error collection: selecting stars or radio sources distributed evenly in a star catalogue for tracking and observation to obtain the theoretical position and measurement position of the stars, and subtracting the measurement positions and the theoretical positions to obtain the error distribution; error model fitting: selecting a suitable orthogonal spherical cap function for the obtained error distribution and performing fitting to calculate an error fitting coefficient, the orthogonal spherical cap function model comprising a hemispheric harmonic function HSH, a Zernike spherical cap function ZSF, and a longitudinal spherical cap function LSF; and error control and compensation: putting the error model and the related fitting coefficient into a pointing control system for compensation.
    Type: Application
    Filed: September 14, 2020
    Publication date: December 22, 2022
    Inventors: Yi ZHENG, Ying LI, Zhaoxiang WU, Bin LIANG, Lifeng TANG