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This paper develops an adaptive digital autopilot for a fixed-wing aircraft and compares its performance with a fixed-gain autopilot. The adaptive digital autopilot is constructed by augmenting the autopilot architecture implemented in PX4…

Systems and Control · Electrical Eng. & Systems 2021-10-25 Joonghyun Lee , John Spencer , Juan Augusto Paredes , Sai Ravela , Dennis S. Bernstein , Ankit Goel

The aberrations induced by the sample and/or by the sample holder limit the resolution of optical microscopes. Wavefront correction can be achieved using a deformable mirror with wavefront sensorless optimization algorithms but, despite the…

Controlling the shape of deformable linear objects using robots and constraints provided by environmental fixtures has diverse industrial applications. In order to establish robust contacts with these fixtures, accurate estimation of the…

Robotics · Computer Science 2024-01-31 Kejia Chen , Zhenshan Bing , Yansong Wu , Fan Wu , Liding Zhang , Sami Haddadin , Alois Knoll

The paper discusses an assessment study about the impact of the distortions on the astrometric observations with the Extremely Large Telescope originated from the optics positioning errors and telescope instabilities. Optical simulations…

Instrumentation and Methods for Astrophysics · Physics 2018-06-06 Gabriele Rodeghiero , Jörg-Uwe Pott , Carmelo Arcidiacono , Davide Massari , Martin Glück , Hannes Riechert , Eric Gendron

Optical aberrations of optical systems cause significant degradation of imaging quality. Aberration correction by sophisticated lens designs and special glass materials generally incurs high cost of manufacturing and the increase in the…

Computer Vision and Pattern Recognition · Computer Science 2023-04-13 Shuang Cui , Bingnan Wang , Quan Zheng

Exposing an Evolutionary Algorithm that is used to evolve robot controllers to variable conditions is necessary to obtain solutions which are robust and can cross the reality gap. However, we do not yet have methods for analyzing and…

Neural and Evolutionary Computing · Computer Science 2023-10-13 Jonata Tyska Carvalho , Stefano Nolfi

This paper considers the controllability analysis problem for a class of multirotor systems subject to rotor failure/wear. It is shown that classical controllability theories of linear systems are not sufficient to test the controllability…

Systems and Control · Computer Science 2016-02-23 Guang-Xun Du , Quan Quan , Binxian Yang , Kai-Yuan Cai

There are different techniques to sense the wavefront phase-distortions due to atmospheric turbulence. Curvature sensors are practical in their sensitivity being adjustable to the prevailing atmospheric conditions. Even at the best sites,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Aglae Kellerer , Mark Chun , Christ Ftaclas

We present an experiment set to address a standard specification aiming at avoiding local turbulence inside the Coud\'e train of telescopes. Namely, every optical surface should be kept within a 1.5$^\circ$ range around ambient temperature.…

The next generation of large ground-based optical and infrared telescopes will provide new challenges for designers of astronomical instrumentation. The varied science cases for these extremely large telescopes (ELTs) require a large range…

Astrophysics · Physics 2009-11-13 Colin Cunningham , Chris Evans , Guy Monnet , Miska Le Louarn

A rigid-flexible manipulator may be assigned tasks in a moving environment where the winds or vibrations affect the position and/or orientation of surface of operation. Consequently, losses of the contact and perhaps degradation of the…

Robotics · Computer Science 2007-05-23 Atef A. Ata , Habib Johar

In projectors and head-mounted displays, an out-of-focus image appears blurred. Even when a display itself is in focus, computer operation may be hindered if the display is far from the user or if a user has poor visual acuity, because the…

Human-Computer Interaction · Computer Science 2026-04-28 Ryuto Tomihari , Taiki Kinoshita , Yosuke Oba , Shota Yamanaka , Homei Miyashita

The major cornerstone of future ground-based astronomy is imaging and spectroscopy at the diffraction limit using adaptive optics. To exploit the potential of current AO systems, we have begun a survey around bright stars to study…

Astrophysics · Physics 2007-05-23 R. I. Davies , M. Lehnert , A. J. Baker , S. Rabien

In this paper, adapted from the author's PhD thesis, we present otherwise unpublished results relating to global control schemes, culminating in the calculation of a fault-tolerant threshold for one such scheme. As with early fault-tolerant…

Quantum Physics · Physics 2007-05-23 Alastair Kay

The measurement and correction of optics parameters has been a major concern since the advent of strong focusing synchrotron accelerators. A review of typical imperfections in accelerator optics together with measurement and correction…

Accelerator Physics · Physics 2020-06-19 R. Tomás , X. Buffat , J. Coello , E. Fol , L. Malina

Multifocal plane microscopy (MUM) allows three dimensional objects to be imaged in a single camera frame. Our approach uses dual orthogonal diffraction phase gratings with a quadratic distortion of the lines to apply defocus to the first…

Optics · Physics 2020-03-13 Benjamin Gore , Noah Schwartz , Paul Dalgarno

In this work, we consider a group of robots working together to manipulate a rigid object to track a desired trajectory in $SE(3)$. The robots do not know the mass or friction properties of the object, or where they are attached to the…

Robotics · Computer Science 2021-08-23 Preston Culbertson , Jean-Jacques E. Slotine , Mac Schwager

Micro-electro-mechanical systems (MEMS) technology can provide for deformable mirrors (DMs) with excellent performance within a favorable economy of scale. Large MEMS-based astronomical adaptive optics (AO) systems such as the Gemini Planet…

In this paper, we investigate the impact of higher-order distortions on the precise measurement of weak gravitational lensing shear and flexion. We begin by defining generalized higher-order distortions and outlining methods for measuring…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Yuki Okura , Toshifumi Futamase

Spectrographs nominally contain a degree of quasi-static optical aberrations resulting from the quality of manufactured component surfaces, imperfect alignment, design residuals, thermal effects, and other other associated phenomena…

Instrumentation and Methods for Astrophysics · Physics 2021-07-28 Eric B. Bechter , Andrew J. Bechter , Justin R. Crepp , Jonathan Crass