Importance of structural damping in the dynamic analysis of compliant deployable structures

• The nonlinear response of tape springs is studied using finite element models.
• Analysis of numerical and structural damping׳s influence on the numerical response.
• Both structural and numerical dampings are required for a valid simulation.
• Accounting for structural damping reduces the dependency to numerical parameters.
• Accounting for structural damping ensures the correct representation of deployment.

Compliant mechanisms such as tape springs are often used on satellites to deploy appendices, e.g. solar panels, antennas, telescopes and solar sails. Their main advantage comes from the fact that their motion results from the elastic deformation of structural components and the absence of actuators or external energy sources. The mechanical behaviour of a tape spring is intrinsically complex and nonlinear involving buckling, hysteresis and self-locking phenomena. In the majority of the previous works, dynamic simulations were performed without any physical representation of the structural damping. These simulations could be successfully achieved because of the presence of numerical damping in the transient solver. However, in this case, the dynamic response turns out to be quite sensitive to the amount of numerical dissipation, so that the predictive capabilities of the model are questionable. In this work based on numerical case studies, we show that the dynamic simulation of a tape spring can be made less sensitive to numerical parameters when the structural dissipation is taken into account.