Pinhole camera model

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A multi-energy soft x-ray (SXR) pinhole camera has been built, calibrated and deployed on the WEST tokamak to aid the study of thermal plasmas. This novel imaging diagnostic technique employs a 2D pixelated x-ray detector in which the lower energy threshold for photon detection can be adjusted independently on each pixel. This innovation allows the simultaneous measurement of x-rays with space, time and energy resolution. Measurements at lower energy (2-6 keV) dominated by tungsten line emission are used to

Pixelated differential phase contrast (DPC) is a four-dimensional scanning transmission electron microscopy (4D-STEM) technique in which the position of the transmitted beam is tracked to reconstruct the electromagnetic fields of a sample. Although it can provide (semi-) quantitative information for a range of different applications, the measurements are greatly affected by the microscope's optical and acquisition settings in terms of sensitivity, accuracy, and spatial resolution, particularly when measurin

Bayesian statistics is concerned with the integration of new information obtained through observations with prior knowledge, and accordingly, is often related to information theory (Jospin 2022). Recursive Bayesian estimation methods, such as Kalman Filters, have long been the de facto approach for Smooth Best Estimate of Trajectory (SBET) computations (Aslan 2021). Recently, the robotics and geodetic engineering communities have proposed to use an alternative approach referred to as Dynamic Networks (Rouza

We propose a novel application of pose estimation to precisely measure the hand ﬁnger width via noisy RGB-D image. A framework is developed that estimates the ﬁnger width given data from TrueDepth camera as well as the target ﬁnger measure- ment location. Moreover, handPifPaf, a new bottom-up 2D hand pose estimator, is introduced and integrated with the width estimation pipeline. This network performs on a par with the state of the art hand pose estimators on public hand datasets. An extensive 2D annotated

Modifying the moduli of supporting convexity and supporting smoothness, we introduce new moduli for Banach spaces which occur, for example, as lengths of catheti of right-angled triangles (defined via so-called quasiorthogonality). These triangles have two ...

We present a longitudinal-differential (LD) phase distribution near the focus of a high numerical aperture (NA=0.9) aplanatic lens illuminated with a linearly polarized monochromatic plane wave. The Richards and Wolf method is used to compute field distributions. The LD phase map is obtained by analyzing the deviation of the phase of the simulated wave to the phase of a referential plane wave. We discuss the irregular wavefront spacing that is linked to the Guoy phase and disclose subtle details of the phas

High-concentration solar-power optics require precise two-axis tracking. The planar micro-optic solar concentrator uses a lenslet array over a planar waveguide with small reflective facets at the focal point of each lenslet to couple incident light into th ...

Solar concentrator systems rely on focusing a large collecting aperture onto a small one where a high efficiency solar cell is placed. The main drawback of concentrator systems is the need to track the direction of the sun. We report on the development of a trackfree planar solar concentrator which employs a self-adaptive light responsive mechanism. The working mechanism is based on optical trapping reflective particles dispersed into a liquid waveguide. The trapping effect experienced by the reflective par

We present a CMOS imager with built-in capability to perform Compressed Sensing. The adopted sensing strategy is the random Convolution due to J. Romberg. It is achieved by a shift register set in a pseudo-random configuration. It acts as a convolutive filter on the imager focal plane, the current issued from each CMOS pixel undergoing a pseudo-random redirection controlled by each component of the filter sequence. A pseudo-random triggering of the ADC reading is finally applied to complete the acquisition

In the most populous metropolis, the world's largest fish wholesale market, the Tsukiji market, needs to expand. Land is too expensive to afford, but a quarter of the central districts remain underused. Relocate the fish market! Having reached its geographical limits, Tokyo has expanded on the sea. The strip of reclaimed land dividing the central wards from the sea is called the Tokyo Bay Area. Left out from the tight network of public transportation, it remains disconnected and difficult to access. No real

We propose an approach to incorporating dynamic models into the human body tracking process that yields full 3--D reconstructions from monocular sequences. We formulate the tracking problem is terms of minimizing a differentiable criterion whose differential structure is rich enough for successful optimization using a single-hypothesis hill-climbing approach as opposed to a multi-hypotheses probabilistic one. In other words, we avoid the computational complexity of multi-hypotheses algorithms while obtainin

This paper presents general ideas on design and implementation of robots to be used together with groups of animals. This work is part of the European project LEURRE aiming to study, model and control mixed societies of animals and robots. After a short presentation of the general project, the implications on the special requirements will be discussed. The design process of the robot will be described leading to the implementation of the autonomous mini robot called InsBot. This is very compact (19x30x41 mm

This paper describes the design methodology to build an autonomous mobile robot of just few cubic centimeters (2 x 2 x 2 cm). Starting from the expected features, the design path will be shown, going through solution proposition, component search, subsystems interconnections, several versions and ending to the final product. The second part of the paper will be dedicated to the control of such a robot which has implications in the control and software architecture. The overall design cycle results in the la

We present a new method for reconstructing digitally recorded off-axis Fresnel holograms. Currently-used reconstruction methods are based on the simulation and propagation of a reference wave that is diffracted by the hologram. This procedure introduces a twin-image and a zero-order term which are inherent to the diffraction phenomenon. These terms perturb the reconstruction and limit the field of view. Our new approach splits the reconstruction process into two parts. First, we recover the amplitude and th

We describe a new experimental approach whereby an indoor flying robot evolves the ability to navigate in a textured room using only visual information and neuromorphic control. The architecture of a spiking neural circuit, which is connected to the vision system and to the motors, is genetically encoded and evolved on the physical robot without human intervention. The flying robot consists of a small wireless airship equipped with a linear camera and a set of sensors used to measure its performance. Evolve

The design and first results are presented from a bolometric diagnostic with high temporal resolution recently installed on the TCV tokamak. The system consists of two pinhole cameras viewing the plasma from above and below at the same toroidal location. Each camera is equipped with an AXUV-16ELO linear array of 16 p-n junction photodiodes, characterized by a flat spectral sensitivity from ultraviolet to x-ray energies, a high temporal response (< 0.5 mu s), and insensitivity to low-energy neutral particles

Pinhole camera model

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Novel soft x-ray multi-energy camera to study thermal plasmas on WEST

Assessing the electric field sensitivity measured by pixelated differential phase contrast imaging in vacuum both in the absence of external fields and under field-bound conditions

From Probability Graphical Models to Dynamic Networks — A Bayesian perspective on Smooth Best Estimate of Trajectory with applications in Geodetic Engineering

Precise Hand Finger Width Estimation via RGB-D Data

New Moduli For Banach Spaces

Longitudinal-differential phase distribution near the focus of a high numerical aperture lens: Study of wavefront spacing and Gouy phase

Two-axis solar tracking accomplished through small lateral translations

Trackfree Planar Solar Concentrator System

CMOS Compressed Imaging by Random Convolution

Tokyo Fish-Eye. Développement du pôle Waterfront-Subcenter. Relocalisation du marché de gros de poisson Tsukiji

Monocular 3-D Tracking of the Golf Swing

InsBot: Design of an Autonomous Mini Mobile Robot Able to Interact with Cockroaches

Design and Control of the Mobile Micro Robot Alice

A Novel Non-Diffractive Reconstruction Method for Digital Holographic Microscopy

Evolving Vision-based Flying Robots

Fast bolometric measurements on the TCV tokamak