Negative stiffness elements in a lumped system allows high damping. It matters where the damping is placed in a three element system, based on analysis. Use of columns with flat ends, free to tilt, allows high damping combined with high stiffness equal to that of parent material, shown in experiment. Stable modules based on this concept exhibit high stiffness and high damping as shown in experiment. Inertia in lumped three element systems does not alter stability conditions, based on analysis. Singular damping can occur in three element systems with inertia, based on analysis. Large hysteresis occurs in post-buckling provided flat end rods can tilt so contact goes from surface to edge. Negative incremental stiffness in these systems occurs in the post buckling regime. Effective tan delta exceeds 0.7 in such systems. |