PROJECT CENTOR: PREPARING THE DESIGN OF FUTURE ORBITAL TRANSFER VEHICLES

摘要

Orbital transfer vehicles (OTV) had been widely studied in the past, especially in the 70-80's as a complement of reusable launch vehicles (RLV), such as the US Space Shuttle, but no reusable orbital transfer vehicles has ever flown. Today, the context is different: the objective of a cost-efficient RLV is receding in the roadmaps, but the need for orbital mobility remains and gets even higher, if we consider new kinds of missions, such as on-orbit servicing, space-debris related missions and reconfiguration of space systems. This paper presents Onera's Centor project (French acronym for "Reusable Orbital Transfer Vehicles Concepts"), an internally funded initiative, whose objective is to study the interest of orbital transfer vehicles for new kinds of missions, such as the one mentioned above, and at the same time preparing the methodology for the design of this kind of vehicle. Centor's objective is not - by itself - the early design of a single future vehicle (as an industrial project could be), but rather a set of activities to develop tools and methods to get prepared to design OTV solutions for future needs. OTV design is studied under the angle of Multidisciplinary Design Optimization (MDO), and Centor is a part of Onera's efforts to develop MDO activities for the design of aerospace vehicles. Current Centor activities are focused on space-based vehicles using two propulsion and maneuvering technologies: cryogenic propulsion, which is the chemical rocket propulsion system.with the best performance in terms of specific impulse, and aeroassistance, which is a potentially interesting technique to perform certain types of orbital transfers with no fuel consumption. The first part of the paper gives an overview of possible missions of OTVs, explains the rationale for revisiting the concept of orbital transfer vehicles, and details the context and hypotheses of the Centor study. The second part of the paper gives an overview of ongoing Centor activities, which are focused on the multidisciplinary design optimization of two vehicles: an all-propulsive (cryogenic) vehicle and an aeroassisted vehicle. We focus on the MDO process of the cryogenic aeroassisted transfer vehicle, which is the most demanding case in terms of coupling between the different disciplines involved. A review of the different tools and models is given as well as the status of the current MDO process. Finally, on overview of future activities is given.