We develop tracking control laws for a rigid spacecraft using both thrusters and momentum wheels. The model studied comprises a rigid body with external thrusters and with N rigid axisymmetric wheels controlled by axial torques. The thruster torques and the axial motor torques are the controls used to track given attitude motions. Specifically, the thruster torques are used to implement the coa...

Since the Russian launch of the Zond-2 satellite in 1964 there have been over fifty years of research dedicated to the understanding of the first electric propulsion device to be flown in space, the Pulsed Plasma Thruster. The Pulsed Plasma Thruster originates from the evolution of the vacuum arc switch, but due to its microsecond operation time, the internal dynamics and nature of operation ha...

Despite some advancements in the field, Hall thrusters are still typically simulated using quasi-1D codes that assume thermalized potential along magnetic field lines and an analytical model for the cross-field mobility. In this paper, we develop methodology and present results from a Hall thruster simulation which diverges from this approach in two important aspects. First, a two-dimensional m...

Space manipulators mounted on an on-o thrustercontrolled base are envisioned to assist in the assembly and maintenance of space structures. When handling large payloads, manipulator joint and link exibility become important, for they can result in payload-attitude controller fuel-replenishing dynamic interactions. In this paper, the dynamics model of an Nexible-joint space manipulator is develo...

The design of the Linear Gridless Ion Thruster, or LGIT, is presented in detail. The LGIT is a hybrid thruster that combines an ionization stage similar to those normally found on gridded ion engines with the acceleration mechanism of a Hall effect thruster. This thruster also features a linear geometry, which simplifies the design of the magnetic circuit while making the LGIT particularly well...

We propose the use of a model helicopter to emulate the landing dynamics of a spacecraft. Our controller accepts thruster inputs (like those on a spacecraft) and converts them into appropriate helicopter stick controls such that the resulting trajectory of the helicopter is close to the trajectory that would have been achieved by simply providing the same thruster inputs to a spacecraft. The ap...

Computational analysis of the transport of boron eroded from the walls of a Hall thruster is performed by implementing sputter yields of hexagonal boron nitride and velocity distribution functions of boron within the hybrid-PIC model HPHall. The model is applied to simulate NASA’s HiVHAc Hall thruster at a discharge voltage of 500V and discharge powers of 1–3 kW. The number densities of grounda...

The UAH-78AM is a low-power Hall effect thruster developed at the University of Alabama in Huntsville with channel walls and a propellant distributor manufactured using 3D printing. The goal of this project is to assess the feasibility of using unconventional materials to produce a low-cost functioning Hall effect thruster and consider how additive manufacturing can expand the design space and ...

Existing models have developed computational Hall thruster codes to a level where qualitative features of the plasma and electric field can be reproduced. These results are possible only with the use of corrections to various transport and energy parameters; however, these corrections are not rigorously defined by the actual physics governing these processes. This paper presents a 2-D hybrid PI...