Comparative Study Using CAD Optimization Tools for the Workspace of a 6DOF Parallel Kinematics Machine

This paper deals with an up-to-date topic among robotic industrial applications that require a high degree of speed, rigidity, and orientation. Currently, when technology and software applications reach a high level of performance, in various robotic industrial applications that start from certain concepts, the implementation of efficient structures has proven to be challenging. New structures such as the parallel kinematic machine (PKM) category has proven its efficiency through its structure in terms of high inertia rigidity and high speeds during processes. This paper deals with the subject of PKM-type structures in terms of the optimal design workspace of such a structure. The calculation of the workspace is considered the premise from which it starts in terms of its implementation in a robotic production line. The entire process of calculating the workspace for a given PKM structure is carried out through modern CAD applications that have specific modules in place in this direction. CATIA V5 offers the possibility through the product engineering optimizer module, simulation and calculation of different scenarios aimed at identifying the volume of the workspace for a PKM structure. In the article, we demonstrate the relations between the robot workspace and the design parameters, a method that can also be applied for other parallel structures. The method is useful for robot designers in the optimization of parallel robots with regard to the workspace by using CAD tools. Previous research in the field refers of the usage of CAD tools only for visual representation and not for optimizing the workspace, while this study and test results show that CAD tools are suitable for analyzing and optimizing the robot workspace of the 6DOF parallel robot, due to its easiness in application and fast implementation time

Cast Iron Parts Obtained in Ceramic Molds Produced by Binder Jetting 3D Printing—Morphological and Mechanical Characterization

Mechanical behavior and characteristics of two different types of materials: cast iron with lamellar graphite EN-GJL-250 and cast iron with spheroidal graphite EN-GJS-400-15 which were cast in ceramic molds using gravitational casting method has considered in this research. The ceramic molds were obtained by 3D printing method. First, a finite element analysis was developed to determine Tresca and von Mises stresses and the deformations of the ceramic molds under an applied pressure of 25 MPa. Samples were produced by gravitational casting using two types of cast iron materials. Mechanical tests were made using samples produced from these two types of materials and microstructure analysis evaluation of fractured zones was realized by scanning electron microscopy. Obtained results were finally used for designing, developing, and producing of one ‘hydraulic block’ of a railway installation by the Benninger Guss company of Switzerland