Saša Ćuković

Modeling of the Meshing of Trochoidal Profiles With Clearances

This paper explains development of the general mathematical model of trochoidal gearing that can be applied for gerotor pumps and cyclo reducers. The model analyzes geometry and physics of the gearing pair in trochoidal pump where the outer gear has one tooth more than the inner gear. The inner gear profile is described by peritrochoid equidistance and the outer gear profile by circular arc. Mathematical model of gearing with clearances is based on the principle of an ideal profile development. Minimum clearance height between teeth profiles in relation to instantaneous gear ratio is determined. The influence of gear profile geometrical parameters on gearing process, clearance height change, and pulsation of drive moment is analyzed and presented in numerical examples. Obtained results can be used for the design of the trochoidal gearing where accurate and silent operation is required. [DOI: 10.1115/1.4005621]

Developing curriculum in bioengineering and medical informatics at Western Balkan Universities

The broad fields of Bioengineering (BE) and Medical Informatics (MI) are among the most prominent and fastest developing scientific areas. These are considered as key, out of a few, challenges within crucial research and innovation strategies worldwide. Almost every university wanting to be in accordance with a technological progress offers a curricula in BE&MI at master and doctoral levels, and numerous offer bachelor level degrees, as well. Where it is not the case, state and universities authorities are making efforts to open dedicated study programs. Following the evident needs European Commission promotes such actions through its educational strategies and corresponding projects, Tempus being one of these. The Education, Audiovisual and Culture Executive Agency (EACEA) granted regional Tempus project “Studies in Bioengineering and Medical Informatics - BioEMIS” aiming at introducing devoted study programs at Western Balkan countries, namely Serbia, Montenegro, and Bosnia and Herzegovina. The following short study highlights the main guidelines of BE&MI study programs development, respecting European good practice.

Development of 3D parametric model of human spine and simulator for biomedical engineering education and scoliosis screening

Engineering education has been changing during the time and starting to cover many interdisciplinary and multidisciplinary fields. We are witnessing the growing importance of biomedical engineering (BME). It leads to increasing needs for development of effective education in BME on the one side, and development of different models and simulation tools for both education and medical purposes on the other hand. BME is a highly interdisciplinary field, influenced by various other engineering and medical fields. This article describes the instrumentation, technique and the results in development of 3D parametric model of human spine and its kinematics using 3D computer aided modeling and simulation. Based on 3D parametric model of spine, software for simulation and visualization of scoliosis (deformation of spine) is also developed. The presented solutions, 3D model and scoliosis simulator could improve education in the field of BME and become useful tool in spinal deformities detection and treatment.

Nonlinear control systems - A brief overview of historical and recent advances

Abstract Last five decades witnessed remarkable developments in linear control systems and thus problems in this subject has been largely resolved. The scope of the present paper is beyond linear solutions. Modern technology demands sophisticated control laws to meet stringent design specifications thus highlighting the increasingly conspicuous position of nonlinear control systems, which is the topic of this paper. Historical role of analytical concepts in analysis and design of nonlinear control systems is briefly outlined. Recent advancements in these systems from applications perspective are examined with critical comments on associated challenges. It is anticipated that wider dissemination of this comprehensive review will stimulate more collaborations among the research community and contribute to further developments.

Augmented Reality Simulation of CAM Spatial Tool Paths in Prismatic Milling Sequences

Augmented Reality (AR) technology to support learning activities becomes a trend in education and effective teaching aids for engineering courses. This paper presents initial results of a project aimed to transform the current learning process of Computer Aided Manufacturing (CAM) by designing and implementing an interactive AR learning and simulation tool to help students to develop a comprehensive understanding of technological models and features in milling processes. We present a marker-based platform that uses AR as a medium for representation of prismatic milling processes to facilitate CAM education and it should enable a faster comprehension of complex spatial paths and overall machining system.

Lathe Machining in the Era of Industry 4.0: Remanufactured Lathe with Integrated Measurement System for CNC Generation of the Rolling Surfaces for Railway Wheels

Many projects and researches in the field of remanufacturing of specialized lathes are presented in the specialized literature. In the process of design for remanufacturing, a great number of solutions contain different aspects and data important to consider. The paper presents important stages of theoretical and applied research regarding the modernization of a conventional lathe with two working units by adaptation of four driving chains for CNC advance/positioning movements and improvements of translation couplings, adaptation of CNC equipment for driving and measuring simultaneous both wheels mounted on axle. The reducing of geometrical errors of the running profile is very important in reshaping the worn wheelsets. The lathe remanufacturing process involves the restoration of functional requirements and measurement of the geometric precision. The CNC capabilities of the remanufactured lathe require a database of parametric representation of profiles and rolling surfaces using CAD techniques according to international standards.

3D modeling and simulation of scoliosis — An integrated knowledgeware approach

This paper presents the application of knowledgeware technologies and CAD systems in the field of 3D non-invasive diagnosis of idiopathic spinal deformity, primarily scoliosis. Automation of the process of generating key diagnostic indicators and a 3D model of the spine, based on digitized dorsal surfaces of patients, is achieved by implementing VBA macros and specialized modules of the CATIA v5 PLM system. Approximation of the central spinal line is performed by B-Spline function whose analysis generates a series of diagnostic parameters that describe the external and internal manifestations of deformities and create preconditions for internet-based monitoring and visualization.

Parametric Modeling of Surfaces Using CATIA v5 Environment

The goal of the CAD parametric modeling is to create a 3D representation, flexible and complex enough to encourage the engineer to easily consider a variety of designs with the cost of applying changes as low as possible. Geometric modeling systems provide a virtual environment similar to the real one in which the physical model is constructed/designed and manipulated. Using such a system, the engineer models, adds, deforms and edits parts in the process of detailing a shape. The virtual model may look the same as the real physical model, but it’s intangible. However, the 3D virtual model is accompanied by its mathematical description, parameters, restraints and these eliminates the need of measurements for prototyping or mass production, can be modified at any modeling phase, can be tested in various ways etc., which is a major disadvantage of using a physical part. This paper presents some theoretical aspects regarding the design process of products including surfaces and a few case studies showing the many possibilities in creating complex surfaces using the CATIA v5 software.

A Framework for Technology Enhanced Education in Orthopaedics: Knee Surgery Case Study

The paper presents a framework for technology enhanced education (TEE) in orthopaedics aimed at employment of ubiquitous information and communication technology (ICT) and digital technologies in order to compensate for an unaffordable learning environment. On the other side, the concept involves both (bio)engineers, ICT specialists, and orthopaedic surgeons in an interprofessional collaboration, leveraging multidisciplinary approaches to improve the quality of clinical-oriented education. Preliminary results indicate increased motivation and satisfaction of both the learners and educators.

Design of Handle Elevators and ATR Spectrum of Material Manufactured by Stereolithography

In medicine, the surgical instruments are realized using a variety of stainless steel, such as curved elevators. The quality and the price of surgical instruments differ in function of the manufacturing processes and the material used. This paper, presents a prototype of elevator, manufactured using two types of additive manufacturing process Direct Metal Laser Sintering – DMLS process for beaks and stereolithography process for the handles. The handle was made by means of stereolithography with the printer PROJET 1500, using a plastic material D638. The design and the quality obtained for the prototype of elevator is better, thanks to the material used and to the manufacturing process. The prototype of handle manufactured by stereolithography using the UV rays presents very good mechanical resistance and allows to be sterilized. For the handle of the elevator prototype there was performed a FEM analysis to identify stress locations and displacements. In this paper, was realized a Attenuated Total Reflection (ATR) analysis on the plastic material D638 to be examined directly in the solid state without further preparation.