Uncertainty quantification of an inflatable/rigidizable torus

There is an increasing interest in lightweight inflatable structures for space missions. The dynamic testing and model updating of these types of structures present many challenges in terms of model uncertainty and structural nonlinearity. This paper presents an experimental study of uncertainty quantification of a 3m-diameter inflatable torus. Model uncertainty can be thought of as coming from two different sources, uncertainty due to changes in controlled conditions, such as temperature and input force level, and uncertainty associated with others random factors, such as measurement noise, etc. To precisely investigate and quantify model uncertainty from different sources, experiments, using sine-sweep excitation in the specified narrow frequency bands, are conducted to collect frequency response function (FRF) under various test conditions. To model the variation of the identified parameters, a singular value decomposition technique is applied to extract the principal components of the parameter change.