Sasa Zivanovic

A New 3-DOF Spatial Parallel Mechanism for Milling Machines with Long X Travel

It is well known that the shape and volume of the workspace are one of the greatest weaknesses of parallel kinematic machine tools (PKM). Hexaglide and Triaglide mechanisms are examples where workspace extension is achieved by elongating one axis as a principal motion axis that is a common feature of all Cartesian machines. With the idea of principal axis of motion in mind, a new 3-DOF spatial parallel mechanism for horizontal and vertical milling machines has been developed. In comparison with similar developed mechanisms it has several advantages such as: rather regular shape of the workspace (slightly modified block) similar to serial machines; greater stiffness by nature of the struts arrangement; good force and speed ratio through the entire mechanisms workspace. The paper describes the structure of the mechanism, modelling approach and simulation on a developed vertical milling machine prototype.

Modelling and Analysis of 3-Axis Reconfigurable Hybrid Kinematics Mechanism with Translatory Actuated Joints

Modelling and analysis of a 3-axis reconfigurable hybrid kinematic mechanism is shown in this paper. Generalized model for solving the inverse and direct kinematic problem is presented. Generalized equations show the solution of kinematic problems of hybrid mechanism applied for any configuration of reconfigurable machine. 3-axis hybrid mechanism consists of a 2-axis parallel mechanism and added serial translatory axis. Chosen characteristic mechanism configurations are shown as the realization examples. Workspace is determined for chosen configurations and possible singular mechanism positions are analysed.