Improved RCSA technique for efficient tool-tip dynamics prediction

• A new receptance coupling method to accurately predict tool-tip FRF is developed.
• Translation and rotational FRFs of the machine are identified with a single test.
• An inverse RCSA approach is formulated to extract required FRFs of the machine.
• No additional experimental phase is required to compute rotational FRF.
• Accuracy of the method is proven by experimental validation on different tools.

Chatter prediction requires Frequency Response Function (FRF) at the tool-tip, which can be reliably identified by modal testing. However this procedure is time-consuming and unsuitable for industrial application since measurements must be performed for each tool attached to the machine. Receptance coupling technique can be adopted to speed up FRF identification. This technique computes tool-tip response combining experimental spindle-holder dynamics with numerical/analytical model of the tool. The main drawback is to identify rotational degree of freedom responses that are generally obtained by performing additional calibrations tests. This work presents a new method overcoming this limitation, obtaining rotational responses by a novel inverse formulation that reduces the number of required experiments. The proposed method is based on receptance coupling theory and requires FRF measurements of a single machine setup, thus increasing the efficiency of receptance coupling approach for tool-tip FRF prediction. The proposed technique is proven by experimental validation and the same accuracy of state of the art methods is obtained.