Clusters of low-performance spacecraft flying in formation may provide enhanced performance over single high-performance spacecraft. This is especially true for remote sensing missions where interferometry or stereographic imaging may provide higher resolution data. The configuration of such formations vary during an orbit due to orbital dynamics, and over larger time scales due to perturbation...

This paper proposed a nonlinear robust control for spacecraft attitude based on passivity and disturbance suppression vector. The spacecraft model was described using quaternion. The control law introduced the suppression vector of external disturbances and had no information related to the system parameters. The desired performance of spacecraft attitude control could be achieved using the des...

Several upcoming European and American space missions will be operated using a number of spacecraft flying in formation. The associated scientific challenges are demanding, both with respect to the construction of the spacecraft as well as to the mission design. For instance, energy efficient trajectories and corresponding control laws that enable precision formation flying over long periods of...

Flux-Pinned Interfaces are a developing technology for spacecraft that exploit flux pinning, a phenomenon in superconducting physics, to manipulate the dynamics between two spacecraft modules. Flux pinning occurs in certain types of superconductors which, when cooled below their critical temperature, will resist changes to the distribution of magnetic flux that was present during the temperatur...

NASA is working aggressively toward greatly reducing the life-cycle costs of planetary, space physics, astrophysics, Earth observing, and communications missions. In order to pursue important programs in space and Earth science and commercial applications of space in the twenty-first century, frequent, affordable missions are required. These are enabled through a fundamental paradigm shift in t...

NASA has recently announced the New Millennium Program (NMP) to develop \faster, better, cheaper" spacecraft in order to establish a \virtual presence" in space. A crucial element in achieving this vision is onboard spacecraft autonomy, requiring us to automate functions which have traditionally been achieved on ground by humans. These include planning activities, sequencing spacecraft actions,...

On February 12, 2001, the NEAR Shoemaker spacecraft made its historic descent to the surface of the asteroid 433 Eros, becoming the first spacecraft to soft land on a small celestial body. Development of the final descent activity offered the NEAR team a difficult technical challenge as the spacecraft had been designed solely as a free flyer, not as a lander. The NEAR Shoemaker spacecraft rende...

Studies of the Earth with the ATS-5, ATS-6, and SCATHA spacecraft led to the development of several simple tools for predicting the potentials to be expected on a spacecraft in the space environment. These tools have been used to estimate the expected levels of worst case charging at Jupiter and Saturn for the Galileo and the Cassini spacecraft missions. This paper reviews those results and put...

This paper investigates the problem of synchronizing the chaotic attitude dynamics of multiple spacecraft is investigated based on the distributed predictive control approach. Kinematic and dynamic equations are used to describe the spacecraft system according to the Modified Rodriguez Parameters representation. The respective method follows the sequential and cooperative structure of distribut...

This paper describes spacecraft formation control and sensing research with application to a Separated Spacecraft Interferometer. A multi-layer control design that achieves very accurate alignment between spacecraft is described. Sensing for this control architecture is based on a global real-time relative position and orientation estimator that uses Carrier Di erential-phase GPS measurements. ...