Peculiarities of the Grinding Process of a Gear Hob Helical Rake Face

This paper presents a study regarding the gear hob’s rake face grinding possibilities and its consequences. A simple theoretical lined surface is considered. The mathematical model of the reciprocate meshing of surfaces was applied. It was proven that the proposed form of the rake face cannot be obtained because an undercut of inacceptable extent occurs. It is also proven and sustained by CAD modeling that using a simplified, flat grinding disk, the undercut is avoided, but the phenomenon of transection appears.

Automatic Parametric Modeling From Non-Feature Based Designs for Additive Manufacturing

The integration of Topology optimization (TO) and Generative Design (GD) with additive manufacturing (AM) is becoming advent methods to lightweight parts while maintaining performance under the same loading conditions. However, these models from TO or GD are not in a form that they can be easily edited in a 3D CAD modeling system. These geometries are generally in a form with no surface/plane information, thus having non-editable features. Direct fabricate these non-feature-based designs and their inherent characteristics would lead to non-desired part qualities in terms of shape, GD&T, and mechanical properties. Current commercial software always requires a significant amount of manual work by experienced CAD users to generate a feature-based CAD model from non-feature-based designs for AM and performance simulation. This paper presents fully automated shaping algorithms for building parametric feature-based 3D models from non-feature-based designs for AM. Starting from automatically decomposing the given geometry into “formable” volumes, which is defined as a sweeping feature in the CAD modeling system, each decomposed volume will be described with 2D profiles and sweeping directions for modeling. The Boolean of modeled components will be the final parametric shape. The volumetric difference between the final parametric form and the original geometry is also provided to prove the effectiveness and efficiency of this automatic shaping methodology. Besides, the performance of the parametric models is being simulated to testify the functionality.

CAD Modeling and Manufacturing of Cleaning Machine used for Waste Collection on Beach

As the difficulties faced in keeping the beaches clean manually, come up with device which not only gathers the waste (sticks, on degradable waste) but also separates, which is easy for waste removal. The waste is collected over conveyor blade along with the sand which falls of through the holes on the conveyor back to the sand bed; separation of waste takes place through Density difference. It consists of one hopper where the different waste gets collected which facilitates easy disposal of waste.

Investigating Students’ Perception on the Outcomes of Technical Drawing University Courses

This paper presents the results of a survey carried out with students enrolled in the first two years of the BS in Engineering at three Italian university locations. The study is part of a wider range of methods, tools and aids for the improvement of teaching and learning of technical drawing at university level developed by the University of Brescia, Udine, and Cassino and Southern Lazio. In particular, this work analyses the results of questionnaires related to the basic technical drawing outcomes, taking inspiration from previous research work in this field. What emerges is a positive picture that shows students’ interest in 3D CAD modeling topics such as part or assembly construction, but also their interest in more traditional subjects like sketching and dimensioning.

Efficiency analysis of a multiport patch antenna

The article considers the patch antenna with several ports to excite a circular polarization. The effect of excitation ports number on the total efficiency of antenna was investigated. Taking into account the mutual coupling of the antenna ports, the total active reflection coefficient was estimated. A comparison of the calculated characteristics and the data obtained by CAD-modeling was carried out. It was shown that the total efficiency of the multiport patch antenna is independent from the number of excitation ports

On the Role of Graph Theory Apparatus in a CAD Modeling Kernel

This paper summarizes the experience of authors in solving a broad range of CAD modeling problems where the formalism of graph theory demonstrates its expressive power. Some results reported in this paper have never been published elsewhere. The set of topological and geometric heuristics backing the subgraph isomorphism algorithm is presented to achieve decent performance in our extensible feature recognition framework. By the example of sheet metal features, we show that using wise topological and geometric heuristics speeds up the search process up to interactive performance rates. For detecting CAD part’s type, we present the connected components’ analysis in the attributed adjacency graph. Our approach allows for identifying two-sided CAD parts, such as sheet metals, tubes, and flat plates. We use the notion of face transition graph for the unfoldability analysis. The basic operations on hierarchical assembly graphs are formalized in terms of graph theory for handling CAD assemblies. We describe instance singling operation that allows for addressing unique part’s occurrences in the component tree of an assembly. The presented algorithms and ideas demonstrated their efficiency and accuracy in the bunch of industrial applications developed by our team.