Multiple Solar Electric Propulsion Technology Demonstration Mission were developed to assess vehicle performance and estimated mission cost. Concepts ranged from a 10,000 kg spacecraft capable of delivering 4000 kg of payload to one of the Earth Moon Lagrange points in support of future human-crewed outposts to a 180 kg spacecraft capable of performing an asteroid rendezvous mission after launc...

Modeling improvements of nonconservative forces affectingMars-orbiting spacecraft are presented in this study. Recent high-resolution gravity fields enable the recovery of smaller signals in the radio tracking data, previously obscured bymismodeled gravitational anomalies. In particular, the estimation of the atmospheric drag experienced by the spacecraft benefits from the new forcemodels.More ...

The idea of using a high-voltage electron beam with substantial current to actively probe magnetic field line connectivity in space has been discussed since the 1970s. However, its experimental realization onboard a magnetospheric spacecraft has never been accomplished because the tenuous magnetospheric plasma cannot provide the return current necessary to keep spacecraft charging under control...

Spacecraft standardization has been a topic of great debate within the space community. This paper intends to be a provocative thought piece asking one fundamental question: “is there a ‘right size’ for small satellites?” In order to answer this question, we propose three top-down design factors for the space systems engineering process: spacecraft utility, mission utility, and optimum cost. Sp...

Fire prevention, detection, and suppression requirements for spacecraft have been developed primarily from established terrestrial and aircraft systems aided by the experience gained from previous space operations. However, the most important factor distinguishing spacecraft fire protection from terrestrial systems is the low-gravity environment that dominates fire and particulate behavior and ...

This paper addresses kinematic control of a redundant space manipulator mounted on a freeoating spacecraft. Redundancy of the system with respect to the number of task variables for spacecraft attitude and manipulator end-e ector pose is considered. Also, the problem of both spacecraft attitude and end-e ector orientation representation is tackled. A nonminimal singularity-free representation o...

We apply retrospective cost adaptive control (RCAC) to spacecraft attitude control with magnetic actuators. We compare two approaches to address the rank deficiency and time-varying nature of the input matrix. The first approach utilizes an average of the magnetic field based on a-priori knowledge, whereas the second approach uses three multi-input, single-output controllers. RCAC uses no infor...

During re-entry into earth’s atmosphere, a spacecraft suffers from loss of communication with the ground control station, known as communication blackout, due to formation of plasma around the re-entry spacecraft. This paper presents the theory and analysis of the communication blackout and its mitigation using static magnetic field method. The interaction between electromagnetic waves and plas...