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Stability of Digital Control System for Unmanned Aerial Vehicle with Numerical Analysis
Thanda Win,
Hteik Tin Cho Nyunt,
Hla Myo Tun
Issue:
Volume 8, Issue 2, June 2020
Pages:
15-18
Received:
20 October 2019
Accepted:
7 April 2020
Published:
17 April 2020
Abstract: The paper presents the analysis on stability of digital control system for unmanned vehicle with numerical analysis. The objective of this study is mainly emphasized on the fulfillment of the advanced control techniques according to the fundamental concepts of digital control system approaches for unmanned aerial vehicle system design. The targeted unmanned aerial vehicle system was designed based on the simple construction under the idea of fixed wing flight system approaches. The stability analyses on unmanned aerial vehicle are vital role to enhance the real world applications. The background concepts on digital control system for stability analysis on dynamic control system like unmanned aerial vehicle system. The appropriate controller design for dynamic control system of unmanned aerial vehicle is vital role to analyze the accurate stability condition for reality. The implementation of numerical analysis on compensator design has been developed by using MATLAB. The physical parameters in these analyses are based on the experimental outcomes from the recent research works in dynamical system implementations. The mathematical approaches are very helpful for numerical analysis on compensator design for the unmanned aerial vehicles schemes. The simulation results confirm that the high performance stability test on unmanned aerial vehicle system has been met with the theoretical works.
Abstract: The paper presents the analysis on stability of digital control system for unmanned vehicle with numerical analysis. The objective of this study is mainly emphasized on the fulfillment of the advanced control techniques according to the fundamental concepts of digital control system approaches for unmanned aerial vehicle system design. The targeted...
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Natural Cause of Galaxy Rotation
Issue:
Volume 8, Issue 2, June 2020
Pages:
19-29
Received:
14 March 2020
Accepted:
28 April 2020
Published:
15 May 2020
Abstract: Presented is a clear description of the mechanism by which galaxies acquire significant rotation. Beneath the apparent random motions and concentrations of galaxies lies the simplicity and regularity of a cosmic-scale cellular structure. It is explained how the dynamics that sustain this cellular structure is responsible for (1) the initial linear motion of galaxies, particularly of ‘field’ ellipticals; (2) the oscillation of the trajectories of galaxies; and (3) the preponderance of gravitational mating of galaxies at favorable locations of the cosmic cellular structure. The importance of the boundaries between cosmic cells is recognized, for this is where the bombardment of galaxies from adjacent cells takes place, leading to random collisions. These collisions, in conjunction with induced trajectory oscillations, result in orbital interactions with varying degrees of angular momentum —from stellar-scale to galactic-scale. As a bonus, the explanation of the so-called random motions of galaxies becomes self-evident and the galaxy morphology-density mystery is resolved. A clear answer is given to the decades old question of why ellipticals dominate the population of the densest regions of a cluster, while spirals are observed to comprise a majority in the elongated (filamentous) region of a cluster.
Abstract: Presented is a clear description of the mechanism by which galaxies acquire significant rotation. Beneath the apparent random motions and concentrations of galaxies lies the simplicity and regularity of a cosmic-scale cellular structure. It is explained how the dynamics that sustain this cellular structure is responsible for (1) the initial linear ...
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A Differential Rotation Law for Stars and Fluid Planets
Joel Uriel Cisneros-Parra,
Francisco Javier Martínez-Herrera,
Daniel Montalvo-Castro
Issue:
Volume 8, Issue 2, June 2020
Pages:
30-34
Received:
31 March 2020
Accepted:
3 May 2020
Published:
15 May 2020
Abstract: We derive, supported on a generalization of Bernoulli’s equation, a law of rotation for any axial-symmetric, self-gravitating fluid mass. For a homogeneous mass, the law depends solely on the derivative of the potential with respect to the distance to the rotation axis, implying generally differential rotation, the Maclaurin spheroids representing the only case of solid-body rotation. We turn then to a heterogeneous mass consisting of any number l of concentric layers, each of constant density, finding that the angular velocity profile of a given layer depends on that of the layer immediately above it. Finally, we let l tend to infinity to convert our model into continuous mass distribution, the result being a certain rotation profile for the surface, and law of differential rotation change at its interior. To support the fundamentals of our approach, we write the potential integrals for the three mass distributions. The aim of a continuous distribution is that it may facilitate a comparison---to be carried out in a future paper---between our results and those of other researchers who employ structure equations. We point out that the distribution of angular velocity is a consequence of the equilibrium, rather than being imposed ad initio. The law was used in a past paper to construct a Jupiter multi-layer model adopting the spheroidal (a distorted spheroid) shape for each of the layers, taking as reference the gravitational data surveyed by the Juno mission. The procedure used here is not restricted to axial-symmetric cases.
Abstract: We derive, supported on a generalization of Bernoulli’s equation, a law of rotation for any axial-symmetric, self-gravitating fluid mass. For a homogeneous mass, the law depends solely on the derivative of the potential with respect to the distance to the rotation axis, implying generally differential rotation, the Maclaurin spheroids representing ...
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Formation and Change of Jupiter's Magnetic Field
Issue:
Volume 8, Issue 2, June 2020
Pages:
35-38
Received:
8 May 2020
Accepted:
25 May 2020
Published:
4 June 2020
Abstract: The existing theory of planetary magnetic field holds that Jupiter has an internal magnetic field similar to the geomagnetic field, it is formed by the agitation of liquid metal hydrogen. But this hypothesis fails to explain many strange properties of Jupiter's magnetic field, especially that Jupiter's magnetic field is changing over time, which was discovered by NASA’s Juno spacecraft. Hence, the hypothesis that Jupiter's magnetic field is internal magnetic field is incredible. Thus, the author analyzed the formation and evolution of Jupiter as well as its internal structure and external environment again, and has found the formation and change of Jupiter’s magnetic field：During Jupiter's rapid rotation, a series of strong polar vortices are produced at the poles of Jupiter. These vortices contain a series of strong spiral currents, which can form a series of strong dipole magnetic fields. The superposition of these dipole magnetic fields form the original magnetic field of Jupiter. Since Jupiter has many massive moons, these satellites are constantly rotating around Jupiter, which has a huge impact on Jupiter's magnetic field. When a massive Jupiter satellite approaches a polar vortex, it can tilt, stretch, shear or break the polar vortex, even draw some sub cyclones out of the polar vortex, and some sub cyclones may turn into cyclones with opposite flow direction. Hence, the destruction of Jupiter's satellites will not only weaken the dipole magnetic field produced by the original cyclone, but also generate some reversed magnetic fields, which can counteract part of the original magnetic field. When this kind of Jupiter moons revolve enough times, the superposition of the generated magnetic fields of opposite direction will cancel out the original magnetic field, finally, making Jupiter’s magnetic field reverse. Therefore, the north pole of Jupiter's magnetic field is near the geographical North Pole, and the south pole of Jupiter's magnetic field is near the geographical South Pole. Hence，the direction of Jupiter's magnetic field is opposite to that of Earth's magnetic field.
Abstract: The existing theory of planetary magnetic field holds that Jupiter has an internal magnetic field similar to the geomagnetic field, it is formed by the agitation of liquid metal hydrogen. But this hypothesis fails to explain many strange properties of Jupiter's magnetic field, especially that Jupiter's magnetic field is changing over time, which wa...
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