Revolute joints play a fundamental role in multibody mechanical systems, including robotic assemblies, internal combustion engines, and linkage mechanisms, by enabling relative rotational motion between connected parts. In real engineering practice, a small amount of clearance inevitably exists between the journal and bearing surfaces because of manufacturing tolerances, material wear, lubrication needs, and assembly inaccuracies. The existence of this clearance can cause repeated contact and separation between the mating components during operation. Such interactions introduce complex nonlinear dynamic responses, which may manifest as vibration, noise generation, elevated stress levels, and a reduction in positioning accuracy as well as component lifespan. Conventional dynamic analyses frequently assume perfectly constrained joints without clearance, which limits their ability to represent the actual behavior of mechanical systems under operating conditions.

The present research is concerned with establishing a dynamic contact–impact model for revolute joints that include clearance, with the objective of improving the understanding of surface interaction during motion. The study specifically examines the influence of important system parameters, including the magnitude of clearance, contact stiffness, damping characteristics, and rotational velocity, on the dynamic response of the joint. A mathematical representation describing the contact and separation behavior between the journal and bearing elements is formulated using recognized contact mechanics principles. Numerical simulation techniques are then applied to determine variations in contact force, frequency of impacts, vibration response, and the motion path of the journal center.

The outcomes of this investigation are expected to enhance the understanding of nonlinear dynamic characteristics associated with revolute joints operating with clearance. These findings can support improved mechanical design by reducing undesirable phenomena such as excessive vibration, surface wear, and operational instability. In addition, the developed modeling approach may serve as an effective predictive tool for evaluating joint performance and increasing the reliability and durability of mechanical systems functioning under practical working environments.

Keywords: Clearance size, Contact stiffness, Damping Coefficient , Journal Bearing ,Revolute joint