Utilizing Electrostatic Force and Mechanical Vibration to Obtain Regolith Sample from the Moon and Mars

Abstract A new design, not reported in the existing literature, combining features of ionic wind and mechanical vibration to induce appreciable airflow is developed. Its feasibility is demonstrated in a cooling system to enhance heat transfer. Ionic wind is generated via using a thin, flexible plate as the emitting electrode and a heated, vertical plate as the collecting electrode. By placing a metal inductor close to the discharge electrode, an electrostatic filed is formed. The electrode is attracted and thus moves towards the inductor owing to the electrostatic force created. To sustain periodic oscillation and produce large vibrational amplitudes, the inductor is grounded using current limiting resistors. Vibrational characteristics are highly dependent on the corona voltage, resistance of the resistor, and position of the induction plate, which are examined in the experiments. It was found that the heat transfer enhancement is not improved at high corona voltages because the ionic wind overwhelms the mechanical effect of vibration. The vibrational effect becomes more prominent at low corona voltages with which the electrical field created by the corona discharge is not so intense. The maximum increase of heat transfer coefficient over that without vibration can be as large as 13.4 % at the lowest corona voltage considered in the tests.

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Motor Using Mechanical Vibration of Multiple Bimorph Beams

Mechanical Engineering Research ◽

10.5539/mer.v7n1p7 ◽

2017 ◽

Vol 7 (1) ◽

pp. 7

Author(s):

Hiroyuki Yaguchi

Keyword(s):

Rotational Speed ◽

Electrostatic Force ◽

Mechanical Vibration ◽

Resonance Energy ◽

Input Voltage ◽

Input Power ◽

Maximum Efficiency ◽

Cantilever Beams ◽

Flexible Material ◽

Output Torque

The present paper proposes a non-magnetic motor with a rotor rotated by the mechanical resonance energy of four bimorph cantilever beams excited by an electrostatic force. The use of a flexible material such as silicon rubber enables conversion of translational vibration to rotary movement in one direction. The rotational speed of the proposed motor increases in proportion to the input voltage when two bimorph beams are used, and the maximum rotational speed was found to be 6,804 rpm when the input voltage was set to 24.6 V. Next, the basic characteristics of a prototype motor with four bimorph cantilever beams, including rotational speed, output torque, and efficiency, were determined experimentally. The experimental results revealed that a maximum rotational speed of 6,370 rpm was obtained when the output torque was 19.6 uNm. The proposed motor was also observed to produce an output torque of 63.7 uNm when the rotational speed was 1,491 rpm. The maximum efficiency was 6.2% when the input power was 0.3 W. For the proposed motor, the volume and weight were reduced by approximately 35%, as compared with a motor from a previous study.

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Bifurcation Analysis and Nonlinear Dynamics of a Capacitive Energy Harvester in the Vicinity of the Primary and Secondary Resonances

10.21203/rs.3.rs-686389/v1 ◽

2021 ◽

Author(s):

Saber Azizi ◽

Hadi Madinei ◽

Javad Taghipour ◽

Hassen M. Oukad

Keyword(s):

Bifurcation Analysis ◽

Energy Harvester ◽

Electrostatic Force ◽

Mechanical Vibration ◽

Efficiency Improvement ◽

Efficiency Enhancement ◽

Secondary Resonances ◽

Dynamic Formulation ◽

Energy Harvesting Devices ◽

Bandwidth Broadening

Abstract The impetus of the present study is to examine the effect of nonlinearity on the efficiency enhancement of a capacitive energy harvester. The model consists of a cantilever microbeam underneath which there is an electret layer with a surface voltage, which is responsible for the driving energy. The packaged device is exposed to unwanted harmonic mechanical excitation. The microbeam undergoes mechanical vibration and accordingly the energy is harvested throughout the output circuit. The dynamic formulation accounts for nonlinear curvature, inertia, and nonlinear electrostatic force. The efficiency of the device in the vicinity of the primary and super-harmonic resonances is examined and accordingly the output power is evaluated. Bifurcation analysis is carried out on the dynamics of the system by detecting the bifurcations in the frequency domain and diagnosing their types. One of the challenging issues in the design and analysis of energy harvesting devices is to broaden the bandwidth so that more frequencies are accommodated within the amplification region. In this study the effect of the nonlinearity on the bandwidth broadening, as well as efficiency improvement of the device, is studied.

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The motion of a lunar orbiter

Symposium - International Astronomical Union ◽

10.1017/s0074180900105686 ◽

1966 ◽

Vol 25 ◽

pp. 373

Author(s):

Y. Kozai

Keyword(s):

Degrees Of Freedom ◽

Dimensional Space ◽

Artificial Satellite ◽

Equations Of Motion ◽

Triaxial Ellipsoid ◽

The Moon ◽

Secular Motion ◽

The Earth ◽

Close Satellite ◽

The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

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Laboratory Simulation of Lunar Luminescence

Symposium - International Astronomical Union ◽

10.1017/s007418090017843x ◽

1962 ◽

Vol 14 ◽

pp. 441-444 ◽

Cited By ~ 1

Author(s):

J. E. Geake ◽

H. Lipson ◽

M. D. Lumb

Keyword(s):

Science And Technology ◽

Laboratory Simulation ◽

The Moon ◽

Physics Department ◽

Luminescent Spectrum

Work has recently begun in the Physics Department of the Manchester College of Science and Technology on an attempt to simulate lunar luminescence in the laboratory. This programme is running parallel with that of our colleagues in the Manchester University Astronomy Department, who are making observations of the luminescent spectrum of the Moon itself. Our instruments are as yet only partly completed, but we will describe briefly what they are to consist of, in the hope that we may benefit from the comments of others in the same field, and arrange to co-ordinate our work with theirs.

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Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

Symposium - International Astronomical Union ◽

10.1017/s0074180900178404 ◽

1962 ◽

Vol 14 ◽

pp. 415-418

Author(s):

K. P. Stanyukovich ◽

V. A. Bronshten

Keyword(s):

Explosive Charge ◽

The Moon ◽

Meteorite Impacts ◽

The Earth ◽

Lunar Craters ◽

The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

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The Origin of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178209 ◽

1962 ◽

Vol 14 ◽

pp. 149-155 ◽

Cited By ~ 1

Author(s):

E. L. Ruskol

Keyword(s):

Chemical Composition ◽

Solar System ◽

The Moon ◽

The Earth ◽

The Difference ◽

Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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The Origin of the Moon and its Relationship to the Origin of the Solar System

Symposium - International Astronomical Union ◽

10.1017/s0074180900178192 ◽

1962 ◽

Vol 14 ◽

pp. 133-148 ◽

Cited By ~ 2

Author(s):

Harold C. Urey

Keyword(s):

Solar System ◽

The Moon ◽

The Past ◽

The Earth ◽

Short Period ◽

Origin Of The Moon

During the last 10 years, the writer has presented evidence indicating that the Moon was captured by the Earth and that the large collisions with its surface occurred within a surprisingly short period of time. These observations have been a continuous preoccupation during the past years and some explanation that seemed physically possible and reasonably probable has been sought.

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A Photographic Map of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178179 ◽

1962 ◽

Vol 14 ◽

pp. 113-115

Author(s):

D. W. G. Arthur ◽

E. A. Whitaker

Keyword(s):

Lunar Surface ◽

The Moon ◽

Map Projection

The cartography of the lunar surface can be split into two operations which can be carried on quite independently. The first, which is also the most laborious, is the interpretation of the lunar photographs into the symbolism of the map, with the addition of fine details from telescopic sketches. An example of this kind of work is contained in Johann Krieger'sMond Atlaswhich consists of photographic enlargements in which Krieger has sharpened up the detail to accord with his telescopic impressions. Krieger did not go on either to convert the photographic picture into the line symbolism of a map, or to place this picture on any definite map projection.

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