In order to improve the work in gability of Stewart-type parallel machine tools,a novel 5-DOF serial-parallel machine tool is proposed.The proposed mechine tool is composed of a 2-TPR/2-TPS special 4-DOF parallel mechanism in series with a rotatable component.It can provide 3 translational DOFs and 2 rotational DOFs. The structural characteristics of this machine tool was discussed.The inverse kinematics solution of this machine tool was deduced by analytical method.It was investigated indetail that how to formulate the decouplinge quation of position parameters.The shape of the work space of this machine tool was described by numerical method.The effects of the change on the structural parameterts to the workspace were studied.The analysis results showed that the structure of this machine tool is simple,the workspace of this machine tool is larger than the Stewart-type parallel machine tools,and this machine tool can machine the workpieces which have complex surfaces.At the same time,there search on the analysis of machine tool in this paper povided a theoretical basis for the further designing and investigating.
