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To acquire planetary soil samples and return the samples to the Earth is an effective solution to understand the geological evolution of early stars. Drilling and coring by only utilizing the compound motions of rotation and penetration can sample subsurface soils relatively efficiently compared to excavating, melting, or digging. To maintain the stratification of soil samples for further analysis,...
Many high-end power machines demand greater bearing performance in terms of running speed, precision, reliability, longevity, noise reduction, etc. An ultrasonic bearing based on Near-Field Acoustic Levitation (NFAL) effect is a kind of emerging noncontact gas bearing. Due to its self-aligning capability, the ultrasonic bearing can steadily run at a high speed under high precision. Actuated by piezoelectric...
Compared with traditional rotary-percussive drills driven by electromagnetic motors, ultrasonic drills show advantages of small size, low power, low weight on bit, and lubrication free, making them available for the extraterrestrial rock sampling, especially for the minor planet with a weak gravitational field. To solve the problem that the conventional percussive ultrasonic drills cannot remove cuttings...
Many high-end power machines demand greater bearing performance in terms of running speed, precision, reliability, longevity, noise reduction, etc. An ultrasonic bearing based on Near-Field Acoustic Levitation (NFAL) effect is a kind of emerging noncontact gas bearing. Due to its self-aligning capability, the ultrasonic bearing can steadily run at a high speed — tens of thousands of revolutions per...
Compared with traditional rotary-percussive drill driven by magnetic motors, ultrasonic drill which usually employs the high frequency longitudinal vibration of Langevin transducer to break down rocks, shows advantages of small size, low power, low axial load, and lubrication free, making it available for the extraterrestrial rock sampling, especially for the minor planet with a weak gravitational...
In order to verify whether a small-scale rotorcraft can fly on Mars, this paper is proposed to establish a Martian atmosphere simulator and to design a hover test stand for coaxial rotorcraft rotor. Since the ultra-low air density of Mars is approximately 1/70 of that on the Earth, it is difficult to obtain enough thrust to lift the rotorcraft against Mars gravity. The proposed Martian Atmosphere...
This paper presents a detailed experimental approach for understanding and optimizing the hover performance of Martian UAV rotor, including a systematic discussion about several coefficients for hover characteristics and a detailed design approach for rotor blades of Martian UAV at Reynolds numbers lower than 50000. The discussed hover performance coefficients include figure of merit, thrust coefficient,...
Conventional ultrasonic drills can drill into rocks using high frequency axial vibration, which feature lower power and lower preload force, thus they could become a very attractive solution for future deep-space exploration. However, drill cuttings cannot be removed effectively with the increase of drilling depth by conventional ultrasonic drills that only driven by longitudinal vibration. To address...
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