| This paper addresses the potential for energy reduction obtained by using dynamic line tension-ing in thruster assisted position mooring systems. Traditionally , mooring systems have been designed in such a way that thruster assistance has not been neccessary under normal environmental conditions. However, as oil production moves into deeper waters, such over-dimensioned mooring systems are n...

Small spacecraft that can be categorized as microsats, nanosats, and picosats has a strong potential for wide applications in communication, scientific experiments, and space exploration. In order to combine the advantages of both electric and chemical propulsion thrusters, a dual-mode microspike based thruster concept is proposed. For a fixed input power, it can operate in either a high-Isp mo...

A CPG based motion control approach is proposed for a biologically inspired underwater thruster with undulating long-fin. The characteristic of rhythmic motion patterns generated by CPG suits well to control the thruster, which has multiple fin rays coupled by membrane. Based on modified Matsuoka model, an artificial CPG controller consisting of ten neural oscillators with sensory information f...

The Class A stellar engine (also known as a Shkadov thruster) is a spherical arc mirror, designed to use the impulse from a star’s radiation pressure to generate a thrust force, perturbing the star’s motion. If this mirror obstructs part of the stellar disc during the transit of an exoplanet, then this may be detected by studying the shape of the transit light curve, presenting another potentia...

A new model of the plasma plume from Hall Effect Thrusters (HET's) is presented. The model includes the self-expansion of the main beam by density gradient electric fields, lowenergy ions produced by resonant charge exchange between beam ions and neutral atoms (ambient and thruster-induced), and angle-dependent elastic scattering of beam ions off neutral atoms. The variation of radial velocitie...

Floating potential and ion current density measurements were taken on the laboratory model NASA-173Mv2 in order to improve understanding of the physical processes affecting Hall thruster performance at high specific impulse. Floating potential was measured on discharge chamber centerline over axial positions spanning 10 mm from the anode to 100 mm downstream of the exit plane. Ion current densi...

Abstract. The Hall thruster is an advanced spacecraft propulsion system that uses electrical power provided by the spacecraft to generate thrust by ionizing and accelerating ions to high velocities. While Hall thrusters have been tested in laboratories for nearly forty years and first flew in space some thirty years ago, little is known about the plasma within these devices. This lack of knowle...

With the aim to reduce cost and increase reliability, MEMS technology penetrates space market and new MEMS components are developed for Space application. Among them, micropropulsion devices is an active field of technological research. Several micropropulsion option are under development : the thrust is produced either from a electrical source (electrical thruster) or a chemical source (chemic...

The Pulsed Plasma Thruster (PPT) is a low cost reliable electric propulsive device that has typical performance within the ranges; specific impulse 300 – 1700 s, Impulse bit 0.06 – 2.6 mN.s and thrust efficiency less than 20%. Past studies have focused on specific aspects to increase performance and understanding, i.e. late time ablation or current sheet canting. Although enlightening, they hav...

This work presents recent results of ongoing investigations into rotating spoke instabilities in Hall thrusters. Recent work by the authors demonstrated large amounts of electron current carried by spokes in the nearanode region in the H6 6-kW laboratory model Hall thruster, and raises the question of whether spokes may play a larger role in electron transport throughout the Hall thruster plume...