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Decentralized overlapping feedback laws are designed fM a formation of unmanned aerial vehicles. The dynamic model of the formation with an overlapping information structure mnstrainl is treated as an interconnected system with overlapping subsystems. Using the mathematical fiamework of the inclusion principle, the interconnected system is expanded into a higher dimensional space in which the subsystems appear to be disjoint. On a subsystem level, a static state feedback controller is designed to robustly stabilize the perturbed nominal dynamics of the subsystem. The design procedure is based on the hierarchical application of convex optimization twls involving linear matrix inequalities. As a final step, the decentralized controllers are contracted back to the original interconnected system for implementation 1

SUMMARYFormation flying of multiple spacecraft is an enabling technology for many future space science missions. However, the co-ordination and control of these instruments poses many difficult design challenges. This paper presents fuel/time-optimal control algorithms for a co-ordination and control architecture that was designed for a fleet of spacecraft. This architecture includes low-level formation-keeping algorithms and a high-level fleet planner that creates trajectories to re-size or re-target the formation. The trajectory and formation-keeping optimization algorithms are based on the solutions of linear and integer programming problems. The result is a very flexible optimization framework that can be used off-line to analyse various aspects of the mission design and in real time as part of an onboard autonomous formation flying control system. The overall control approach is demonstrated using a nonlinear simulation environment that includes realistic measurement noises, disturbances, and actuator nonlinearities.

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Examines the concept of “place attachment” as defined in various disciplines and develops an effective conceptual approach that can be applied to facilities management. Describes the development of a model‐matchmaking process adapted from Passini's model of cognitive mapping. Findings that the emergence of the new economy is undermining our ability to form attachments with people, places and companies. However, one of the unintended effects of this is that it has strengthened the value of place and aroused a longing for community. Moreover, loyalty to an organisation is increasingly determined by social and place attachment. Proposes that further research needs to be undertaken to “engineer out” the negative impacts of flexibility associated with loss of place. States that place attachment presents a challenging view of the world that is contrary to all the received wisdom in facilities management, where flexibility has always assumed an unchallenged position in relation to buildings and people. Concludes that this research area presents many pragmatic design and operational questions for facilities managers.

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