A novel non-contact measurement strategy for large-size inflatable structures based on numerical predictions

Abstract

The deformation characteristics of expansive inflatable structures, like airships, provide essential data for their operation in the stratosphere. However, due to rapid configuration changes in these structures with fluctuating air pressure, obtaining accurate morphological data quickly during testing can be challenging. This paper presents a precise method for predicting deformation in large-scale inflatable structures. A finite element method was employed to meticulously model the inflatable structure, underpinned by an inflatable ring skeleton support, and predict its potential maximum deformation points. Leveraging this predictive model as a guide, we proposed utilizing a laser scanning technique for non-contact measurements of the anticipated maximum deformation sites, aiming to discern the deformation patterns of the structure under varying air pressures. A good agreement between the non-contact measurement results and the numerical simulations affirms the efficiency and precision of the proposed methodology. This non-contact measurement strategy, grounded in finite element predictions, streamlines the measurement process, economizing on time and reducing complexity. Such an approach promises to be invaluable for expansive structures like airships. Furthermore, the insights derived from this non-contact method will be pivotal for anticipating the mechanical behaviors of full-scale stratospheric airships during their operations and for refining their design models.