Complete Semi-Analytical Damper Model Identification Using Triangular Displacement Inputs

This research explores possibility of improved liquid damper identification based on the systematic use of the triangular piston displacement inputs. Both static and dynamic damper characteristics are studied to ensure complete problem characterization. Static characteristics are associated with resistive hydraulic features. Dynamic or transient characteristics are primarily associated with mechanical and liquid elasticity in dampers. Measured and simulated damper responses induced by the triangular inputs are studied in order to understand transient damper behaviour. This research looks at the use of the initial transient responses acquired during triangular excitation tests for model and parameter identification. A previously developed single-state dynamic model of the symmetric damper is refined and used in these studies. Measured data acquired from the industrially deployed helicopter damper are used to evaluate the proposed model and its ability to predict transient responses. This study indicates that a more detailed non-constant compressibility model can be successfully applied in single-state damper models.