Validation of the finite element model of a machine tool structure using idealized models - a case study

The machine tool structure provides housing for other functional sub-systems and withstands the gravitational, cutting and dynamic forces and torque without undergoing much deformation. Unlike most of the structures, the machine tool structure has to be designed for rigidity in both static and the dynamic cases. Several modelling methods including graphical methods, scale models and analytical models have been used in the design of the machine tool structure. Due to the complexity of the machine tool structure most of the models developed, are approximated to some idealised models consisting of simple elements such as beams, elastic springs, plates, boxes, etc. Modem computers and associated Finite Element Software provide enormous analytical power to the designer. However the first step in getting valid results from Finite Element Analysis is the validation of the model. In this paper a validation of a Finite Element model using idealised models is discussed. The method is proven through the design of a radial drilling machine tool structure used by Taylor [8].