scholarly journals Genetic Algorithm in the Computation of the Camera External Orientation

2012 ◽  
Vol 9 ◽  
pp. 5-16
Author(s):  
Rudolf Urban ◽  
Martin Štroner
Keyword(s):  
Genetic Algorithm ◽  
Coordinate System ◽  
Control Points ◽  
Generic Algorithm ◽  
Matrix Inverse ◽  
Computation Procedure ◽  
Spatial Coordinate ◽  
The Matrix ◽  
Computer Based ◽  
Calculation Models

The article addresses the solution of the external orientation of the camera by means of a generic algorithm which replaces complicated calculation models using the matrix inverse. The computation requires the knowledge of four control points in the spatial coordinate system and the image coordinate system. The computation procedure fits very well computer-based solutions thanks to it being very simple.

scholarly journals On-Orbit Calibration of Installation Parameter of Multiple Star Sensors System for Optical Remote Sensing Satellite with Ground Control Points

2020 ◽  
Vol 12 (7) ◽  
pp. 1055
Author(s):  
Yanli Wang ◽  
Mi Wang ◽  
Ying Zhu
Keyword(s):  
Remote Sensing ◽  
Coordinate System ◽  
Statistical Characteristics ◽  
Optical Remote Sensing ◽  
Star Sensor ◽  
Control Points ◽  
Remote Sensing Images ◽  
Multiple Star ◽  
Ground Control Points ◽  
Combination Modes

Owing to the vibrations and thermal shocks that arise during the launch and orbit penetration process, the on-orbit installation parameters of multiple star sensors are different from the on-ground measured parameters, causing inconsistencies in the attitude determinations from different combination modes and seriously affecting the geometric accuracy of high-resolution optical remote sensing images. This study presents an on-orbit calibration approach for the installation parameters of a multiple star sensors system using ground control points (GCPs). Based on the on-ground installation parameters of the optical axes of conventional star sensors, a fiducial coordinate system is proposed as the calibration coordinate system. The installation parameters of the conventional star sensors are calibrated using the statistical characteristics of angles between axes of the star sensor and three fiducial vectors in the J2000 celestial coordinate system. Based on the GCPs, the relative fiducial parameters are calculated, and the installation parameter of unconventional star sensor is then calibrated with the relative fiducial parameters and statistical characteristics of angles. It can be used for high-resolution optical remote sensing satellite measuring with only two star sensors to unify the fiducial coordinate system. The proposed method is tested using simulated data and on-orbit measurement data. The results demonstrate that the proposed method can calibrate the optical axis of the star sensor without the restriction of the accuracy of horizontal axis. Moreover, the star sensor with a large installation angle error can be calibrated well using the proposed approach. The results of attitude determinations from different star sensor combination modes are consistent, and the geometric accuracy of the remote sensing images is significantly improved.

Data Modeling Using NURBs Curves and Modified Genetic Algorithms

2010 ◽  
Author(s):  
Christopher Hammond ◽  
Cameron J. Turner
Keyword(s):  
Genetic Algorithm ◽  
Genetic Algorithms ◽  
Trial Data ◽  
Data Sets ◽  
Control Points ◽  
Nurbs Curve ◽  
B Splines ◽  
Modified Genetic Algorithm ◽  
Nurbs Curves ◽  
2D Data

Non-Uniform Rational B-Splines (NURBS) curves have long been used to model 1D and 2D data because they are efficient to calculate, easy to manipulate, and capable of handling discontinuities and drastic changes in the general topology of the data. However, the user must assist in defining the control points, weights, knots and an order for the curve in order to fit the curve to the data. This paper uses a modified Genetic Algorithm (GA) to choose and manipulate these various parameters to produce a NURBS curve that minimizes the error between the data and the curve and also minimizes the time it takes the algorithm to compute the solution. The algorithm is tested on several 1D trial data sets and the results are explained. Then, several general difficulties for this application of the GA are explained and possible methods for overcoming them are discussed.

Instability and Unbalance Response of Dissymmetric Rotor-Bearing Systems

1988 ◽  
Vol 110 (3) ◽  
pp. 288-294 ◽  
Author(s):  
P. M. Guilhen ◽  
P. Berthier ◽  
G. Ferraris ◽  
M. Lalanne
Keyword(s):  
Differential Equations ◽  
Coordinate System ◽  
Transfer Matrix ◽  
Differential System ◽  
Industrial Application ◽  
Floquet Theory ◽  
Unbalance Response ◽  
Stationary Coordinate System ◽  
The Matrix ◽  
The Stability

The study deals with the instability and unbalance response of dissymmetric rotors, when periodic differential equations are impossible to avoid. The method which yields motion instability is based on an extension of the well-known Floquet theory. A transfer matrix over one period of the motion is obtained, and the stability of the system can be tested with the eigenvalues of the matrix. To find the instability and the unbalance response, the Newmark formulation is used. Here, the dissymmetry comes either from the rotor or from the bearings in such a way that it is possible to solve a regular differential system without periodic coefficients, either in the stationary coordinate system or in the rotating one. Three examples are given, including an industrial application. The results show that the method proposed is satisfactory.

scholarly journals Determination of Settings of a Tilted Head Cutter for Generation of Hypoid and Spiral Bevel Gears

1988 ◽  
Vol 110 (4) ◽  
pp. 495-500 ◽  
Author(s):  
F. L. Litvin ◽  
Y. Zhang ◽  
M. Lundy ◽  
C. Heine
Keyword(s):  
Spiral Bevel Gears ◽  
Computation Procedure ◽  
Bevel Gears ◽  
Pressure Angle ◽  
The Matrix ◽  
Spiral Bevel ◽  
Basic Equations

Kinematics of mechanisms of hypoid and spiral bevel cutting machines is considered. These mechanisms are designated to install the position and tilt of the head cutter. The tilt of the head cutter with standard blades provides the required pressure angle. The authors have developed the matrix presentation of kinematics of these mechanisms and basic equations for the required settings. An example is presented based on the developed computation procedure.

D-Wave and predecessors: From simulated to quantum annealing

2014 ◽  
Vol 12 (03) ◽  
pp. 1430002 ◽  
Author(s):  
Eliahu Cohen ◽  
Boaz Tamir
Keyword(s):  
Genetic Algorithm ◽  
Image Processing ◽  
Large Scale ◽  
Quantum Computer ◽  
Research Area ◽  
Hill Climbing ◽  
Quantum Annealing ◽  
Challenging Research ◽  
Computer Based ◽  
D Wave

On May 2011, D-Wave Systems Inc. announced "D-Wave One", as "the world's first commercially available quantum computer". No wonder this adiabatic quantum computer based on 128-qubit chip-set provoked an immediate controversy. Over the last 40 years, quantum computation has been a very promising yet challenging research area, facing major difficulties producing a large scale quantum computer. Today, after Google has purchased "D-Wave Two" containing 512 qubits, criticism has only increased. In this work, we examine the theory underlying the D-Wave, seeking to shed some light on this intriguing quantum computer. Starting from classical algorithms such as Metropolis algorithm, genetic algorithm (GA), hill climbing and simulated annealing, we continue to adiabatic computation and quantum annealing towards better understanding of the D-Wave mechanism. Finally, we outline some applications within the fields of information and image processing. In addition, we suggest a few related theoretical ideas and hypotheses.

Application of Genetic Algorithm for Nozzle Parameters Optimization of Waterjet Propulsion System

2012 ◽  
Vol 157-158 ◽  
pp. 604-607
Author(s):  
Xuan Ling ◽  
Xu Dong Wang
Keyword(s):  
Genetic Algorithm ◽  
Cfd Simulation ◽  
Simulation Analysis ◽  
Optimization Technique ◽  
Propulsion System ◽  
Parameters Optimization ◽  
Integrated Method ◽  
System A ◽  
Design Cycle ◽  
Computer Based

Waterjet propulsion system have been increasingly used in the world due to its advantage of good maneuverability, operability, less vibration etc. The full understanding of waterjet reaction thrust is the preliminary step for the design of waterjet system. A recent research in this area is optimizing the nozzle structure of waterjet propulsion system to increase the waterjet reaction thrust as much as possible. In order to obtain the optimal parameters of nozzle, a new integrated method combining genetic algorithm with CFD simulation analysis is put forward in this paper. The integrated method will not only shorten the system design cycle, it will also develop optimization technique to realize the potential of computer based design automation. Finally, the optimal results are presented and discuss.

Sign in / Sign up

Export Citation Format

Share Document