Dynamics Modeling and Conceptual Design of a Multi-tethered Aerostat System

Canadian researchers have proposed a design concept for a new radio telescope which uses a large multi-tethered aerostat to support and position the telescope’s receiver. Based on encouraging results from an initial dynamics analysis of the system, it was decided to build a one-third scale experimental model of the system for further study. This work focuses on the development of both the dynamics model and the physical design of the scaled experimental system. The dynamics analysis began by scaling the original system using a dimensional analysis to ensure dynamic similarity. Several modifications were made to the dynamics model, broadening its capabilities and improving its approximation of the real system. These included accurate estimation of tether damping properties through experimental methods, the addition of vortex shedding oscillations with the spherical aerostat and the incorporation of a streamlined aerostat. A linear stability analysis of the streamlined aerostat was conducted. The conceptual design of the experimental system is also presented. The selection of the aerostat and tethers was based on choosing available components that provided the most favorable performance. A winching system for the tethers was designed based on results from the dynamics model.

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