Joint identification of modular tools using a novel receptance coupling method

The demand for modular tools in machining operations has been increasing, owing to their flexibility, reduced cost, and productivity improvements when compared to solid carbide tools. Essentially, modular tools are interchangeable cutters that are assembled together with a joint. The effects of joint dynamics are often neglected when characterizing the dynamics of assembled mechanical systems, due to the assumption of rigid connections. In such cases, deviations between real and predicted system dynamic responses are inevitable. To prevent chatter vibration in machining operations, the accurate prediction of the dynamics of the tools is critical. In this study, the classic receptance coupling technique is enhanced by identifying the joint dynamics between substructures through experimental and finite-element (FE) analyses. The rotational dynamics of a substructure is indirectly identified using a gauge tool. The characteristics of a fastener joint (such as mass, spring and damping elements) are identified. Further, with the identified joint dynamics, the dynamic properties of the modular tools with the new interchangeable carbide tools are also predicted. Various experiments have been performed to verify the effectiveness of the joint identification method for modular tools. The method enables designers to optimize dynamic behaviour in the conceptual design stage of modular tools to improve productivity while minimizing chatter vibrations.