Nonlinear design analysis of centrifugal pendulum vibration absorbers: an intrinsic geometry-based framework

The centrifugal pendulum vibration absorber (CPVA) is a device whose purpose is the reduction in torsional vibrations in rotating and reciprocating machinery. Over the last decades, CPVA nonlinear behavior has been thoroughly investigated. In particular, the performance and the local stability of cycloidal, epicycloidal and tautochronic CPVAs have been extensively analyzed. In this paper, on the basis of intrinsic geometry and higher-path curvature theory, a novel and unified modeling approach for the design of a parametric family of CPVAs, herein named lambda-CPVA, is proposed. In the first part, the intrinsic geometry framework is applied to derive CPVA equations of motions in terms of higher-order curvature ratios of the damper path. Then, the same approach is extended to describe the curvature kinematics of the rollers of a parallel bifilar pendulum. In the second part, a new family of parametric curves in R-3, denoted as lambda-curves, is introduced. This allows a fine adjustment ofCPVAnonlinear dynamics to the design requirements. In the third part, the numerical comparison of the performance and the stability limits between the cycloidal, tautochronic pendula and lambda-CPVA are presented. Finally, the lambda-CPVA analytical model is more accurately simulated with a multibody dynamics approach. The design analysis framework herein proposed increases the dimension of the solution space and opens new possibilities of tailoring the CPVA performance to the specific application.