The task of the mixed pure CAD generating method developed by the authors consists in finding only the points situated on the gear tooth surface. The use of the mixed CAD gear generating method results in a very large and particular type of Points Cloud: This contains points situated both in the tooth space, and on the tooth surface. The existing filtering programs and methods, as it was presented in previous papers, cannot deal with these particular point sets. The development of the named particular generating method claims an algorithm and a computer software which can find the envelope of the Points Cloud. This papers presents an Alpha Shape algorithm based filtering algorithm, adapted and developed to be used together with the mixed CAD generating software.
Constraint equations for complex robot structures can lead to a large number of equations. Also, constraint equations permits universal solutions for various mechanisms and solving a large number of equations can be simplified with numerical solutions. Therefore, if discreet solutions are allowed, a universal way to determine the necessary control parameters of a mechanism for different positions, or corresponding positions for different driving parameters is to use constraint equations. A direct kinematical analysis of a 2 DoF spherical mechanism with two driving axes is presented; a numerical simulation is made for given arm dimensions; according to specified degrees of freedom, a simplified CAD model is built and driven with the angular parameters.
Zoltán Forgó, Ferenc Tolvaly-Roșca and Judit Pásztor
The metering shaft of the drilling machine is driven from the impeller. The standard traditional gearbox, the Norton gearbox, provides a constant rotating motion between the impeller and the metering shaft. Manufacturers have started to replace this gearbox with an intermittent rotating movement. Using the stepless variable speed gearbox, the speed of the metering shaft and thus the seed rate is set steplessly. The aim of the thesis is the mathematical modeling of the intermittent rotating motion of the seed drill of a particular drilling machine, and the creation of a striping model.
Ferenc Tolvaly-Rosca, András Kakucs, Zoltán Forgó and Márton Máté
The paper proposes a comparative FEM analysis of gears solid model bodies, obtained with three different methods. The analytical method is based on the mathematical equations of the tooth flanks. It supposed to be the most accurate and precise solid modeling process. However, it reveals it’s limits by handling of surfaces that are not deduced mathematically, or in case of tooth geometries which needs to be modified in order to perform a quick test regarding the probably effects of the mentioned modifications. The solid subtraction- and the newly developed, mixed CAD method are pure CAD generating methods. As any discrete generating method, their precision is influenced by the fineness of the iteration steps. In case of the mixed CAD solution the precision is influenced by the filtering algorithm applied to the generated Points Cloud. The visual comparison of the three mentioned methods, was presented in previously published papers. The present paper validates the novel mixed CAD method comparing the FEA analysis of the generated solid models.