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Showing 1 to 19 of 19 for “"Spacecraft Propulsion"”.
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Spaceborne centrifugal relays for spacecraft propulsion
Acceleration using centrifugal relays is a recently discovered method for the acceleration of spaceborne payloads to high velocity at high thrust. Centrifugal relays are moving rotors which progressively accelerate reaction mass to higher velocities. One important engineering problem consists of …
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A Low Power Pulsed Arcjet Thruster for Spacecraft Propulsion
A pulse-forming electrical circuit is developed to reduce energy losses in the storage capacitor, and greater than 85% of the initial stored energy is transferred to the arc in a unipolar pulse. A high current diode installed across the capacitor terminals is used to eliminate voltage reversals in …
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Electromagnetic extraction and annihilation of antiprotons for spacecraft propulsion
… performance potential of antiproton fuels for spacecraft propulsion, a modified rocket equation with relativistic corrections and variable mass-energy conversion efficiency is derived. Antimatter engines operating via the catalysis of nuclear fission in a fissile material by antiprotons are …
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Collimation of deuterium / 3-helium fusion products for advanced spacecraft propulsion and power
… will most likely require a new generation of propulsion system. One potential technology class to provide spacecraft propulsion and power systems involve thermonuclear fusion plasma systems. In this class it is well accepted that d-He3 fusion is the most promising of the fuel candidates for …
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Ionic liquid ion source emitter arrays fabricated on bulk porous substrates for spacecraft propulsion
… a wide range of temperatures. When applied to spacecraft propulsion these sources are very power efficient and yield high specific impulses. Furthermore. the low flow rates and negligible vapor pressures of ionic liquids allow for passive feeding systems which can remain exposed to the vacuum …
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Power balance in a helicon plasma source for space propulsion
Electric propulsion systems provide an attractive option for various spacecraft propulsion applications due to their high specific impulse. The power balance of an electric thruster based on a helicon plasma source is presented. The power balance is shown to be comprised of several variables, …
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Investigation Into the Mitigation of the Effects of Uncertain Optical Degradation on an Interplanetary Solar Sail Mission Using a Single Model Update
… interest in using solar sails as a source of spacecraft propulsion has been accompanied by a recent fervor of investigations into non-ideal and off-nominal sail performance considerations. One of the most influential considerations, uncertain optical degradation, has been shown to present …
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Towards Electrical Control Over Rocket Propellant Combustion
… the functionality and performance of various propulsion systems. In solid rocket motors, active burn rate modulation has the potential to enable throttling. In spacecraft propulsion systems, electrolysis of propellants may provide a means to reduce energy requirements and eliminate the need …
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Colloid Thruster to Teach Advance Electric Propulsion Techniques to Post-secondary Students
… are meeting the demands of small satellite propulsion. As such, in an effort to keep the spacecraft propulsion curriculum current with today’s technology, a colloid thruster is designed, built, tested, and implemented as a laboratory activity at California Polytechnic State University, San …
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Study of optical propulsion concepts and techniques for small-satellites
… metallic, nanostructures for plasmonic force propulsion, a developing method of nano-/picosatellite thrust generation. This project developed a higher-fidelity model of a recently envisioned small spacecraft propulsion system for precision pointing and proximity control. Plasmonic force …
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Separated spacecraft interferometry : system architecture design and optimization
… the trade space for future optical separated spacecraft interferometers (SSI's) is explored. Using Distributed Satellite System principles, eleven separate architectures ranging in size from three to five spacecraft are compared on the basis of four metrics: 1) capability, 2) performance, 3) …
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Design of a Bimodal Chemical-Electrospray Propulsion System using Ionic Liquid Monopropellants
Two primary propulsion modes currently exist for spacecraft: chemical (e.g. monopropellant, cold gas, solid propellant) and electric (e.g. Hall thruster, ion engine, electrospray). Chemical propulsion typically offers high thrust and low specific impulse, while electric propulsion provides the …
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Small-Body and Heliophysics Missions using Hybrid Low-Thrust Propulsion
… of increasingly efficient and powerful propulsion systems. However, all of these systems, from the earliest chemical engines to modern electric thrusters, require propellant, thereby reducing the mass budget available for a payload. By harnessing the momentum of reflected photons of …
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3D plume modeling of SPT-100
Hall thrusters are a spacecraft propulsion device for orbit maintenance and north-south station keeping. One of the concerns about Hall thrusters is the sputtering of high energy ions which could result in the erosion of sensitive surface coatings used for solar cell elements and thermal control. …
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Optimal control techniques for multimode propulsion mission design in cislunar space
Multimode spacecraft propulsion is an emerging, enabling, and enhancing technology that combines two or more propulsive modes (e.g., chemical and electric) into one system using a single propellant. The primary benefit of this technology is that it can provide reduced propellant consumption for a …
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A Continuum Kinetic Investigation into the Role of Transport Physics in the Bohm Speed formulation
… engineering interest, such as plasma-based spacecraft propulsion engines, where interactions affect the transport properties of the plasma and consequently the performance of the engine. Therefore, gaining a fundamental understanding of the various plasma-material interactions is necessary …
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Spacecraft and Propulsion Technician Error
<p>Commercial aviation and commercial space similarly launch, fly, and land passenger vehicles. Unlike aviation, the U.S. government has not established maintenance policies for commercial space. This study conducted a mixed methods review of 610 U.S. space launches from 1984 through 2011, which …
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Development and Initial Testing of a Micro-Newton Torsion Pendulum with Gas-Dynamic Calibration
… thrust test stand for micro-Newton-scale spacecraft thrusters is described. The stand is designed to be robust against electromagnetic interference effects internal or external to the thruster being tested. The design and testing of a gas-dynamic calibration thruster is included. This …
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Variable Structure Feedback Control with Application to Spacecraft with Small Thrust Propulsion Systems
<p>Small spacecrafts requiring small propulsion systems are becoming more popular for low Earth orbit. It is important for these research satellites to have accurate guidance and control systems. Small propulsion systems will also be beneficial for multiple small spacecrafts used future exploration …