This dissertation focuses on the design, modeling, characterization and experimental verification of a class of nonlinear energy sink, based on a cantilever beam vibrating laterally between two specially shaped surfaces that limit the vibration amplitude, thus providing a variable beam length throughout its deflection, therefore producing a smooth nonlinear restoring force. First, a methodology to evaluate and visualize the energy interactions between the nonlinear energy sink and its host structure is developed. Then, an semi-analytical dynamic model for simulating the device under actual working conditions is proposed, and finally, an experimental verification step is conducted where the numerical results are compared and correlated to the experimental results.