English
Related papers

Related papers: Kalman Filter Estimation for Focal Plane Wavefront…

200 papers

The key to photoelectric X-ray polarimetry is the determination of the emission direction of photoelectrons. Because of the low mass of an electron, the ionisation trajectory is not straight and the useful information needed for polarimetry…

Instrumentation and Detectors · Physics 2021-09-03 Tenglin Li , Ming Zeng , Hua Feng , Jirong Cang , Hong Li , Heng Zhang , Zhi Zeng , Jianping Cheng , Hao Ma , Yinong Liu

Direct detection is a very promising field in exoplanet science. It allows the detection of companions with large separation and allows their spectral analysis. A few planets have already been detected and are under spectral analysis. But…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Raphaël Galicher , Pierre Baudoz , Gérard Rousset

The Hartmann test is a method used to measure the wavefront error in a focal optical system, wherein a mask with a pattern of small holes is placed at the system's aperture stop. By taking an image at a defocused plane, the differences…

The above-mentioned work [1] in IEEE-TR'08 presented an extended Kalman filter for calibrating the misalignment between a camera and an IMU. As one of the main contributions, the locally weakly observable analysis was carried out using Lie…

Robotics · Computer Science 2013-11-26 Yuanxin Wu

The Kalman Filter (KF) parameters are traditionally determined by noise estimation, since under the KF assumptions, the state prediction errors are minimized when the parameters correspond to the noise covariance. However, noise estimation…

Machine Learning · Computer Science 2022-07-04 Ido Greenberg , Shie Mannor , Netanel Yannay

We present a method of using classical wavelet based multiresolution analysis to separate scales in model and observations during data assimilation with the ensemble Kalman filter. In many applications, the underlying physics of a phenomena…

Optimization and Control · Mathematics 2015-11-09 Kyle S. Hickmann , Humberto C. Godinez

We have reported previously on a new method we are developing for using image-based information to improve global coronal magnetic field models. In that work we presented early tests of the method which proved its capability to improve…

Solar and Stellar Astrophysics · Physics 2017-08-02 Shaela I. Jones , Joseph M. Davila , Vadim M. Uritsky

We study the problem of estimating a time dependent magnetic field by continuous optical probing of an atomic ensemble. The magnetic field is assumed to follow a stochastic Ornstein-Uhlenbeck process and it induces Larmor precession of the…

Quantum Physics · Physics 2021-01-04 Cheng Zhang , Klaus Molmer

Fluid pressure and fluid velocity carry important information for cancer diagnosis, prognosis and treatment. Recent work has demonstrated that estimation of these parameters is theoretically possible using ultrasound poroelastography.…

Image and Video Processing · Electrical Eng. & Systems 2018-07-23 Md Tauhidul Islam , Raffaella Righetti

Polarimetric imaging has been applied in a growing number of applications in robotic vision (ex. underwater navigation, glare removal, de-hazing, object classification, and depth estimation). One can find on the market RGB Polarization…

Computer Vision and Pattern Recognition · Computer Science 2022-08-30 Joaquin Rodriguez , Lew Lew-Yan-Voon , Renato Martins , Olivier Morel

The leading difficulty in achieving the contrast necessary to directly image exoplanets and associated structures (eg. protoplanetary disks) at wavelengths ranging from the visible to the infrared are quasi-static speckles, and they are…

Instrumentation and Methods for Astrophysics · Physics 2021-10-04 Richard A Frazin , Alexander T Rodack

Camera calibration is a crucial step in photogrammetry and 3D vision applications. This paper introduces a novel camera calibration method using a designed collimator system. Our collimator system provides a reliable and controllable…

Computer Vision and Pattern Recognition · Computer Science 2025-12-19 Shunkun Liang , Banglei Guan , Zhenbao Yu , Dongcai Tan , Pengju Sun , Zibin Liu , Qifeng Yu , Yang Shang

Inertial measurement units are widely used in different fields to estimate the attitude. Many algorithms have been proposed to improve estimation performance. However, most of them still suffer from 1) inaccurate initial estimation, 2)…

Robotics · Computer Science 2021-07-28 Yujie Tang , Liang Hu , Qingrui Zhang , Wei Pan

The direct detection and characterization of exoplanets will be a major scientific driver over the next decade, involving the development of very large telescopes and requires high-contrast imaging close to the optical axis. Some complex…

Instrumentation and Methods for Astrophysics · Physics 2017-05-16 M. Beaulieu , L. Abe , P. Martinez , P. Baudoz , C. Gouvret , F. Vakili

The technique requires the epipolar geometry to be pre-estimated between each image pair. It exploits the constraints which the camera movement implies, in order to apply a closed-form correction to the parameters of the input affinities.…

Computer Vision and Pattern Recognition · Computer Science 2019-05-03 Ivan Eichhardt , Daniel Barath

We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method…

Instrumentation and Methods for Astrophysics · Physics 2019-03-06 Gregory R. Brady , Christopher Moriarty , Peter Petrone , Iva Laginja , Keira Brooks , Tom Comeau , Lucie Leboulleux , Remi Soummer

Context. Solar wavefront sensing has been a challenge for astrophysical instrumentalists, due to the low contrast between the Sun and the sky background compared to night-time observations, which limits the performance of adaptive optics…

We present a derivation for estimating the roll and pitch orientation of a partially calibrated camera mounted above a planar surface, using minimal scene information. Specifically, we assume known intrinsic parameters and a fixed height…

Computer Vision and Pattern Recognition · Computer Science 2025-07-29 Gergely Dinya , Anna Gelencsér-Horváth

Technological advances have made wireless sensors cheap and reliable enough to be brought into industrial use. A major challenge arises from the fact that wireless channels introduce random packet dropouts. Power control and coding are key…

Information Theory · Computer Science 2013-08-09 Daniel E. Quevedo , Jan Ostergaard , Anders Ahlen

This paper presents a novel filter with low computational demand to address the problem of orientation estimation of a robotic platform. This is conventionally addressed by extended Kalman filtering of measurements from a sensor suit which…

Robotics · Computer Science 2016-12-02 Oscar De Silva , George K. I. Mann , Raymond G. Gosine
‹ Prev 1 8 9 10 Next ›