Preliminary Design of a High Performance Solar Sailing Mission

The Team Encounter participants, Team Encounter, LLC, AeroAstro Inc., and L’Garde, Inc. have recently completed the preliminary design of the Team Encounter spacecraft, Humanity's First StarshipTM. The spacecraft, intended to be launched as a secondary payload on an Ariane 5 launcher in the first or second quarter of 2004, consists of two parts: the Carrier, which transports the Sailcraft beyond Earth’s gravity well and the Sailcraft which transports its payload of 3 kg out of the solar system. The Carrier must provide a stable platform for deployment and separation of the 4900 m solar sail, and will provide for video streaming of the Sailcraft as it begins its journey. The Team Encounter Sailcraft is the first spacecraft with the capability to self propel itself out of the solar system with a combination of performance-enhancing tacking maneuvers and an areal density of 3.4 g/m including payload. The mission analysis made use of an innovative unified Matlab / Satellite Tool Kit model developed by AeroAstro that simulates geometry, attitude and trajectory concurrently. This model was used to optimize motor firing, Sailcraft deployment and mission phasing. The Sailcraft ADCS control scheme was validated via stability analysis and simulation, and the results will be presented in this paper. Introduction The Team Encounter PDR was held February 28 and March 1, 2002 in Houston, TX. This paper provides a technical summary of the design status at PDR especially with respect to the Carrier design (along with its major subsystems), Sailcraft attitude determination and control system, systems engineering, trajectory and mission simulation, assembly, integration, test, launch vehicle integration and the ground segment. The scope of effort for the mission consists of a Space Segment and a Ground Segment. These are in turn broken down into the lower level mission elements, which are identified in Fig. 1. As in any significant engineering project, the PDR effort began with identification of requirements. From the top level product requirements, provided by the Customer, the technical team derived and flowed mission requirements, which in turn flowed into the Space and Ground Segments. The requirements traceability process was flowed down to the subsystem and component level, in order to allow for preliminary identification of spacecraft components and vendors. The requirements flow