Mechatronic design and prototype of a 4-DOFs hot-wire CNC cutting machine

The subject of this paper is the mechatronic design of a 4-DOFs hot-wire CNC cutting machine, which is mainly composed by a conventional Cartesian robot with 3-DOFs, plus one that corresponds to the rotation of a fork, in order to orient the hot-wire during the cutting. The proposed cutting machine is actuated through four stepper motors and controlled in such a way to obtain a CAD-CAM system, which is able to generate both planar and skew ruled surfaces, because of the 3-dimensional motion of the hot-wire that is installed on the fork (end-effector). A prototype was built and several experimental tests have allowed the validation of the proposed mechatronic design.