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Conformal Inkjet Printed Antennas for Small SpacecraftTursunniyaz, Muhammadeziz 01 August 2018 (has links)
Although small spacecraft are small in size and light in weight compared to the conventional satellites, they can offer lots of possibilities for space exploration, scientific observation, data collection and telecommunication. Also, they cost a lot less money than the conventional satellites, and the scientific missions can be planned in a relatively short period of time by using the COTS (Commercial Off-The-Shelf) materials. However, there is a big challenge for the small spacecraft that is the limited surface area of the small spacecraft and the outnumbered components to be mounted on the surface of the small spacecraft. The most obvious one is that the competition for the limited real estate between the antenna and solar cells.
UAVs, also known as drones, have become so popular that it is not only used for military and scientific applications, but also they are available for recreational use for ordinary people. Although they are getting smaller in size so that one can put them in his pocket or on his palm, they are becoming multifunctional, which requires more sensors to be mounted on the surface of the drone to achieve its multifunctionality. For example, a recreational drone can not only take pictures and videos, but also it can transmit the picture or video in real time to the operator, which needs a camera to take the picture or videos and needs an antenna to transmit the recorded data to the operator. This requires that the limited surface area needs to be efficiently used in order to accommodate the multiple needed components. This thesis presented a faster, better and cheaper way of inkjet printing conformal antennas on the cover glass of the solar cells of the small spacecraft or on the wing or other parts of the UAV body to integrate the antenna with the solar panels of the CubeSats or with or directly printing the antenna on the UAV body to efficiently use the limited real estate. Several meshed and solid patch antennas printed on a space certified AF32 glass substrate using the printing procedure outlined in this thesis and measured to verify the effectiveness of the inkjet printing procedures. A high gain reflectarray with optical transparency of 95% was inkjet printed on space certified AF32 glass and BOROFLOAT glass and measured to verify the antenna performance and solar panel efficiency. Measurement results showed that the inkjet printed reflectarray integrated on top of the solar panel has a gain of 21.5 dB. The solar panel efficiency was dropped by around 6% due to the inkjet printed reflectarray on glass.
A simple conformal dual-band antenna for UAV application was designed with ANSYS HFSS and fabricated in the lab using a foam substrate. The measured antenna performances agreed well with the simulation results. This dual-band antenna also can be inkjet printed directly on the wing or other parts of the UAVs using the printing techniques discussed in this thesis.
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A Morphable Entry System for Small Satellite Aerocapture at MarsJannuel Vincenzo V Cabrera (12537673) 12 May 2022 (has links)
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<p>As space agencies look to conduct more scientific missions beyond Earth orbit, low-cost access to space becomes indispensable. Small satellites (smallsats) fulfill this need as they can be developed at a fraction of the cost of traditional large satellites. Consequently, smallsats are being envisioned for planetary science missions at several destinations including Mars. However, a significant challenge for interplanetary smallsats is performing fully-propulsive orbit insertion because modern smallsat propulsion technologies have limited total velocity change capabilities. At destinations with significant atmospheres, this challenge can be circumvented via <em>aerocapture</em>, a technique that uses a single atmospheric pass to convert a hyperbolic approach trajectory into a captured elliptical orbit. Aerocapture has been shown to enable significant propellant mass savings as compared to fully-propulsive orbit insertion, making it an attractive choice for smallsats. Performing aerocapture with smallsats requires a suitable vehicle design that satisfies the associated control requirements and volumetric constraints. To address this requirement, this dissertation proposes the <em>morphable entry system </em>(MES), a conceptual deployable entry vehicle that utilizes shape morphing to follow a desired atmospheric flight profile during aerocapture. The aerocapture performance of the MES at Mars is investigated using a six degree-of-freedom aerocapture simulation environment. The shape morphing strategy employed by the MES is shown to be feasible for targeting desired angle of attack and sideslip angle profiles that lead to successful orbit captures. Furthermore, the robustness of the MES to simulated day-of-flight uncertainties while employing angle of attack control is demonstrated through a Monte Carlo dispersion analysis. The major contributions of this research as well as areas of future work are described.</p>
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