A Configurable Test Bench for Mechanical Clearance Studies: Multibody Modeling and Experimental Features

Mechanical clearances are present in mechanical systems due to manufacturing tolerances, assembly imperfections, wear, and material deformation. Their presence can significantly influence dynamic behavior, vibration levels, and long-term component performance. As a result, the characterization, monitoring, and estimation of clearances have become important research topics. Considerable research has been devoted to the dynamic analysis of mechanical systems with clearances using multibody formulations, while more recent studies have explored hybrid model-based estimation techniques and data-driven methods for clearance identification. The development of such approaches requires experimental platforms capable of systematically reproducing and investigating clearance-induced dynamic behaviors. This work presents the development of a configurable slider–crank test bench designed for experimental investigation of mechanical clearance, which allows the selection of clearance location and magnitude, operating speed, and mechanism orientation. A multibody model was developed to support the system design, monitor its operation, and provide a numerical reference for the obtained experimental data, retrieved from accelerometers and encoders. The results obtained during experimental tests demonstrate that the platform generates repeatable measurements while remaining sensitive to variations in operating conditions and clearance configurations. Results also served to assess the ability of multibody formulations and clearance modeling approaches to correctly characterize the dynamic effects caused by joint clearances. Formulations that describe the system motion using minimal coordinates resulted in reduced uncertainty in simulation results. The selected contact models succeeded at capturing the effect of revolute joint clearances on the accelerations of the mechanism, establishing a first step in the detailed description of the contact dynamics that is necessary for the use of forward-dynamics simulation results in the development of hybrid model-based and data-driven clearance characterization methods.