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The aim of the research work was focused on a research of manipulators design using suction grippers. The results of the research can be applied in the design of jigs - manipulators for handling thin sheets. The FME analysis was used in the investigation to show the course of elastic deformations and stresses in stressed areas. An experimental observation of the change in the free deflection of the workpiece from the positioning of the suction cups under gravity load by means of a laser 3D scanner was carried out for the FEM deflection detection method.

This paper presents the theoretical design for experimental verification of the structural and technological parameters of the Parallel Kinematic Structure. The experimental equipment was developed at the Faculty of Mechanical Engineering, STU in Bratislava. It is called Tricept, and due to its kinematics it is classified as a parallel structure. The previous phase of the project dealt with developing a mathematical model of the tool path. We have worked with two methods, a Monte Carlo method and the use of a mathematical analytical geometry structure. The calculated values were verified by comparing the results of the two methods. Based on the equations that were obtained, we can design the control of the tool path during cutting. The next stage focuses on the test methods and on verifying the structural and technological parameters of Tricept. The experiment is designed on the basis of the EN ISO 9283 standard, and involves testing the technological parameters: one-way positioning accuracy and repeatability of the position, changes of multidirectional positioning accuracy, repeatability and accuracy of the distance, position overshoot, drift of the position parameters, path accuracy, and repeatability of the path. This paper classifies the measurement methods and presents the measurement processes and the equipment for the experiment.

The quality of cutting machines is affected by several factors that can be directly or indirectly influenced by manufacturers, technicians and users of machine tools. The most critical qualitative evaluation parameters of machine tools include accuracy and stability. Investigations of accuracy and repeatable positioning accuracy were essential for the research presented in this paper. The aim was to develop and experimentally verify the design of a methodology for cutting centers aimed at achieving the desired working precision. Before working on the topic described here, it was necessary to make several scientific analyses, which are summarized in this paper. We can build on the initial working hypothesis that by improving the technological parameters (e.g. by increasing the working speed of the machine, or by improving the precision of the positioning) the quality of the cutting machine will also be improved. For the purposes of our study, several investigated parameters were set affecting positioning accuracy, such as rigidity, positioning speed, etc. First, the stiffness of the portal structure of the cutting machine was analyzed. FEM analysis was used to investigate several alternative structures of the cutting machine, and also an innovative solution for beam mounting. The second step was to integrate two types of drives into the design of the cutting machine. The first drive is a classic rack and pinion drive for cutting machines. To increase (improve) the working speed of the machine, linear motors were designed as an alternative drive. The portal of the cutting machine was designed for a working speed of 260mmin−1 and acceleration of 25 m. s−2. The third step was based on the results of the analysis. In collaboration with Microstep, an experimental cutting machine in a portal version was produced using linear synchronous motors driving the portal on both sides, and with direct linear metering of its position. In the fourth step, an experiment was designed and conducted to explore the positioning accuracy and the repeatable positioning accuracy.