We investigate the concurrent problem of orbit design and formation control around a libration point. The problem formulation is based on a framework of multi-agent, nonlinear optimal control. The optimality criterion is fuel consumption modeled as the L 1 -norm of the control acceleration. Fuel budgets are allocated by isoperimetric constraints. The nonsmooth optimal control problem is discretized using DIDO, a software package that implements the Legendre pseudospectral method. The discretized problem is solved using SNOPT, a sequential quadratic programming solver. Among many, one of the advantages of our approach is that we do not require linearization or analytical results; consequently, the inherent nonlinearities associated with the problem are automatically exploited. Sample results for formations about the Sun-Earth L2 point in the 3-body circular restricted dynamical framework are presented. Globally optimal solutions for relaxed and almost periodic formations are presented for both a large separation constraint (about a third to half of orbit size), and a small separation constraint (a few hundred km or about 5 × 10 −6 of orbit size).

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We investigate the concurrent problem of orbit design and formation control around a libration point. The problem formulation is based on a framework of multi-agent, nonlinear optimal control. The optimality criterion is fuel consumption modeled as the L 1 -norm of the control acceleration. Fuel budgets are allocated by isoperimetric constraints. The nonsmooth optimal control problem is discretized using DIDO, a software package that implements the Legendre pseudospectral method. The discretized problem is solved using SNOPT, a sequential quadratic programming solver. Among many, one of the advantages of our approach is that we do not require linearization or analytical results; consequently, the inherent nonlinearities associated with the problem are automatically exploited. Sample results for formations about the Sun-Earth L2 point in the 3-body circular restricted dynamical framework are presented. Globally optimal solutions for relaxed and almost periodic formations are presented for both a large separation constraint (about a third to half of orbit size), and a small separation constraint (a few hundred km or about 5 × 10 −6 of orbit size).

The goal of interface management is to identify, define, control, and verify interfaces; ensure compatibility; provide an efficient system development; be on time and within budget; while meeting stakeholder requirements. This paper will present a successful seven‐step approach to interface management used in several prior NASA flight projects. The seven‐step approach using Model Based Systems Engineering will be illustrated by interface examples from the Materials International Space Station Experiment‐X (MISSE‐X) project. The MISSE‐X was being developed as an International Space Station (ISS) external platform for space environmental studies, designed to advance the technology readiness of materials and devices critical for future space exploration. Emphasis will be given to best practices covering key areas such as interface definition; writing good interface requirements; utilizing interface working groups; developing and controlling interface documents; handling interface agreements; the use of shadow documents; and the importance of interface requirement ownership, interface verification, and product transition.