Search results for "Tamping"

Robust design of a sheet stamping process: approaches to control the inner process variability

2011

The robustness investigation has become a crucial issue in the design of the sheet metal forming operations. The uncontrollable effects of some noise variables heavily influence the final process results, often evolving up to the failure of the process design. Therefore, tools able to handle such variability are worth developing with the aim to minimize the scattering of the investigated process performances despite of the process design. Moreover, the stamping process operations are usually characterized by objectives with conflicting behaviors and a set of compromise solutions, referred as Pareto front, is finally obtained instead of a global optimum. Therefore, the question becomes more …

Analysis of Some Innovative and Flexible Sheet Forming Processes

2002

In the field of sheet forming, innovative and flexible processes that do not impose the use of expensive conventional equipments and/or do not require time consuming set-up operations have become, nowadays, a rather promising research topic. Two different main lines are currently followed: the former is based on the development of new stamping processes based on the utilization of flexible media, while the latter is aimed to develop so called progressive forming processes (spinning and incremental forming). Both hydro-forming and incremental forming permit a very relevant reduction of the tooling and set-up costs and improve process flexibility. These items are discussed in detail in the pa…

A NEW PROGRESSIVE DESIGN METHODOLOGY FOR COMPLEX SHEET METAL STAMPING OPERATIONS: COUPLING SPATIALLY DIFFERENTIATED RESTRAINING FORCES APPROACH AND M…

2010

The growing interest in sheet metal stamping processes, particularly in the automotive industry has led to three main issues in this field:*request of very complex shapes; *growing interest in springback control; *solution of multi-objective problems. These issues make a sheet metal stamping processes design very difficult and proper design methodologies to reduce times and costs are highly required. In this paper, a computer aided approach aiming to satisfy the mentioned issues is proposed. In particular, a progressive design approach based on the integration between numerical simulations, Response Surface Methodology (RSM) and Pareto optimal solutions search techniques was applied in orde…

Tecniche di ottimizzazione multi-obiettivo e metodologie di supporto alle decisioni per la progettazione di processi di stampaggio di lamiere

2010

Active lighting applied to three-dimensional reconstruction of specular metallic surfaces by polarization imaging

2006

International audience; In the field of industrial vision, the three-dimensional inspection of highly reflective metallic objects is still a delicate task. We deal with a new automated three-dimensional inspection system based on polarization analysis. We first present an extension of the shape-from-polarization method for dielectric surfaces to metallic surfaces. Then, we describe what we believe to be a new way of solving the ambiguity concerning the normal orientation with an active lighting system. Finally, applications to shape-defect detection are discussed, and the efficiency of the system to discriminate defects on specular metallic objects made by stamping and polishing is presente…

An integrated approach to the design of tube hydroforming processes: artificial intelligence, numerical analysis and experimental investigation

2004

In the last years, the growing role of process flexibility in modern mechanical industries has driven a rising interest in optimisation of process/product design through innovative techniques. Moreover, the development of niche productions, which are characterised by low production volumes and small batches leads to the need of more flexible and rapid forming technologies. In this way, a great research effort is performed towards the study of new stamping processes: among them hydro forming finds a large interest in automotive industry since it allows to significantly reduce tooling costs and also to avoid some secondary operations. Different studies are available in the technical literatur…

Design of sheet stamping operations to control springback and thinning: a multi-objective stochastic optimization approach

2010

Abstract The aim of this paper is to develop a design tool for stamping processes, which is able to deal with the scattering of the final part quality due to the inner variability of such operations. Such variability is one of the main drawbacks for a robust process design. It results in a scattering of the most significant process results and depends on several parameters. The so called noise factors greatly influence final result variability, which often means rejecting parts and anyway achieving final properties different from the specified ones. The process investigated in the paper is an S-shaped U-channel stamping operation carried out on a lightweight aluminum alloy of automotive int…

"Writing biochips": high-resolution droplet-to-droplet manufacturing of analytical platforms.

2022

The development of high-resolution molecular printing allows the engineering of analytical platforms enabling applications at the interface between chemistry and biology, i.e. in biosensing, electronics, single-cell biology, and point-of-care diagnostics. Their successful implementation stems from the combination of large area printing at resolutions from sub-100 nm up to macroscale, whilst controlling the composition and the volume of the ink, and reconfiguring the deposition features in due course. Similarly to handwriting pens, the engineering of continuous writing systems tackles the issue of the tedious ink replenishment between different printing steps. To this aim, this review articl…

A Comparative Analysis of Different Robust Design Approaches in Sheet Stamping Operations

2011

A crucial issue in sheet stamping optimization problems is related to the process robustness improvement: critical scattering in the investigated performances arises due to some noise variables influence, often evolving up design failure itself. In fact, strong variations in the final stamped part or fluctuations of strain distribution may lead to an uncontrolled process design. Such variability cannot be controlled but anyway it is possible to develop proper design tools able to identify robust process calibrations above which the noises variations effects are admissible. In this paper, a multi‐objective optimization problem was analyzed, with the aim to minimize both excessive thinning an…

Deep drawing versus incremental forming processes: A comparative cradle to gate analysis

2012

The evaluation and reduction of the environmental impact of manufacturing processes have become a crucial issue in the last few years, addressing the interest of industrial and academic research towards greener solutions and technologies. Reducing input materials and energy requirements has become an imperative action in the industrial practice. As a matter of fact, strong is the concern on lightweight solutions and technologies for sheet stamping operations especially in the automotive sector. However, the knowledge on how impactful such processes are is still poor. In this paper, a comparison between a traditional deep drawing and an single point incremental forming process is investigate…