Requirements versus constraints in designing stratospheric platforms for heavy multi-user payloads: The Large-Scale Polarization Explorer (LSPE) expe

In considering the design activities of a stratospheric gondola for a multiuser experiment, the exchange of information between the structural designer and the various teams involved may be a critical issue. In fact, only part of the information is available at the beginning of the project, thus necessitating the use of a trial-and-error approach that leads to results which involve considerable expenditure. For small-and medium-size experiments, the problem of the exchange of information from the mechanical designer's point of view can easily be solved by using a pre-built gondola supplied by a hypothetical launch consortium. This is what we proposed as the "Strato-Bus" approach at the ESA Symposium 2009. Furthermore, in 2011 we also introduced a possible solution of a multi-user gondola design: a shared design for many combinations of experiments, the total weight of which is just below the maximum lift capacity of the balloon produced by several dedicated manufactories. But when the characteristics of the instrumentation make the use of a pre-built platform impossible, the problem of exchanging information arises once again, and this is what we have experienced in the case of the Large-Scale Polarization Explorer (LSPE) experiment. The design activities of the LSPE gondola are used here in order to introduce a "systematic approach" that is capable of saving both time and money for each team involved in the overall project.