Search results for " costruzione."
showing 10 items of 477 documents
Sub-Optimal Control Law for Active Magnetic Bearings Suspension
2012
This paper deals with the comparison of three types of sub-optimal control law for the stable levitation of a turbojet shaft, sustained by two radial active magnetic bearings (AMBs). Shaft is considered rigid for the procedure simplification. The utilized approach leads to development of different sub-optimal control laws to use in speed-varying simulations in the angular speed of the shaft. The first control matrix is obtained by explicit relationships of the parameters of the control law vs. speed, obtained using a curve-fitting procedure neglecting the speed-varying elements out of the main diagonal of each single block constituting the entire control matrix. The second control law is ob…
Comfort-structural analysis in product development Optimization of a motorcycle frame
2012
This work steps from a bachelor thesis, joining the results of a study about the dynamic loads to evaluate the comfort loss in the motorcycle during the usage, with the potentiality of a modern FEM software. The goal is the development of a new methodology for structural optimization of motorcycle’s frame. In many of cases the success of the structural optimization is linked with a two factors combination: the software and the strength of the engineer to condition the mathematical problem, defining parameters domain and technological constraints. A good alternative to the traditional load hypothesis linked to historical data or instrumental measurements is focused in this paper. Consistent …
Computer-aided tool path generation for robotic Non-Destructive Inspection
2013
Compared to manual Non-Destructive Testing (NDT) for inspection of engineering components, automated robotic deployment of the same NDT techniques offers an increase in accuracy, precision and speed of inspection while reducing production time and associated labour costs. Traditionally, the robot tool path is either taught or programmed manually. Automation of NDT tool path generation, as presented in this paper, offers further significant time reduction, and an increase in the flexibility of inspection planning compared to manual robot teaching and programming. Moreover, such a solution helps to maintain a controlled probe orientation with respect to the scanned surface, and thus which can…
Proceedings of the Closed Round Table and Italian Consensus on the Medication-Related Osteonecrosis of Jaws (MRONJ) at the Symposium of Italian Socie…
2019
On 20 October 2018 a Closed Round Table brought together a wide range of stakeholders from several medical disciplines, including academic experts, dentists, oncologists, maxillo-facial surgeons, oral surgeons, radiologists, under the technical and scientific coordination of Giuseppina Campisi (for SIPMO) and Giacomo Oteri (for Italian Society of Oral Surgery- SIdCO).
Environmental aging effects on high-performance biocomposites reinforced by sisal fibers
2023
Among the innovative materials, an important role is played by the so-called biocomposites, generally made by an eco-friendly matrix reinforced with natural fibers. Unfortunately, due to the degradability of the green matrixes as well as to hydrophilicity of the natural fibers, the resistance of such innovative materials to the environmental agents is, in general, relativity low, and it can significantly limit their use in outdoor conditions. To contribute to the knowledge of the effects of the leading environmental agents on the mechanical properties of highperformance biocomposites made of a green epoxy matrix reinforced by agave fibers, a systematic experimental testing campaign has been…
Analysis of the Parameters Affecting the Stiffness of Short Sisal Fiber Biocomposites Manufactured by Compression-Molding
2021
The use of natural fiber-based composites is on the rise in many industries. Thanks to their eco-sustainability, these innovative materials make it possible to adapt the production of components, systems and machines to the increasingly stringent regulations on environmental protection, while at the same time reducing production costs, weight and operating costs. Optimizing the mechanical properties of biocomposites is an important goal of applied research. In this work, using a new numerical approach, the effects of the volume fraction, average length, distribution of orientation and curvature of fibers on the Young’s modulus of a biocomposite reinforced with short natural fibers were stud…
MAPPING MULTIPLE RESIDUAL STRESS COMPONENTS USING THE CONTOUR METHOD AND SUPERPOSITION
2008
The standard contour method determines the residual stress component normal to the plane of measurement. This talk presents extensions to the contour method to allow determination of multiple stress components. Two extensions are presented, both using additional stress measurements and then superposition to determine the original residual stresses. The first extension involves making additional cuts to determine stresses on multiple cut planes, using only the contour method. The second extension involves measuring in-plane stresses on the surface exposed by the original cut, using x-ray diffraction and hole drilling in this case. Experiments were preformed on indented disks of both 316L sta…
ANALISI DELLO STATO TENSIONALE IN RESINE EPOSSIDICHE SOTTOPOSTE AD INVECCHIAMENTO IDROTERMICO MEDIANTE TECNICA FOTOELASTICA
2014
In questo lavoro si è analizzato lo stato tensionale che nasce in sistemi epossidici DGEBA quando sono sottoposti ad invecchiamento idro-termico, tramite la tecnica fotoelastica a trasmissione, basata sul metodo a variazione di fase di Compensazione di Tardy. I provini, monitorati ad intervalli di tempo regolari durante i processi di assorbimento e desorbimento di acqua, sono stati osservati al polariscopio circolare. La tecnica ha permesso di analizzare, sia qualitativamente, sia quantitativamente, lo stato tensionale indotto dal non uniforme “swelling” durante l’intero processo di invecchiamento. Inoltre, lo studio ha analizzato anche provini criccati di tipo Single Edge Notched Bending; …
ROBUST CONTROL FOR A SUSPENDED ROTATING SHAFT BY RADIAL ACTIVE MAGNETIC BEARINGS
2011
This paper shows a comparison based on dynamic behaviour of a rotating shaft when it is suspended by 4-axis active magnetic bearings under several control systems. The control systems used are μ-synthesis, loop shaping design procedure and Sub(H∞) robust control with the introduction of uncertainties on position and current gains of the actuators. Each of these controllers is characterized by four input signals and four output signals and the introduction of uncertainties on displacement gain and current gain is due to torn and worn of the components during the time, which can lead the entire system to instability phenomena. The comparison of the performances is obtained through the introdu…
ERROR AND UNCERTAINTY ANALYSIS OF RESIDUAL STRESS EVALUATION BY USINGTHE RING-CORE METHOD
2014
The Ring-Core Method is a technique used for the experimental analysis of the residual stresses in mechanical components. For uniform and non-uniform residual stresses estimation, the use of the method leads in general to accurate results but, unfortunately at present the user does not have appropriate procedures to correct the obtained results from systematic errors as well as to estimate the uncertainty due to random errors. In order to overcome such drawbacks, in the present work, the procedures for the correction of the effects of the main error sources and for the stress uncertainty estimation, are proposed. The practical application of such procedures allow the user to highlight the r…