Innovative Production Machines and Systems Conference - Special Session: Intelligent and Competitive Manufacturing Eng.

Tool Condition Monitoring in Composite Materials Machining through Neural Network Processing of Acoustic Emission

Segreto — Tue, 03 Jul 2007 08:39:42 +0000

By their nature, composite materials are non-homogeneous, anisotropic, and reinforced with abrasive components. Because of their structure and component properties, composite materials are much more difficult to machine than metal alloys and fall under the category of difficult-to-machine-materials. The composite material workpiece can easily suffer intolerable damage during cutting and the tool wear rate can turn out to be unacceptably high. In addition, the knowledge on the machining of ductile metals is not suitable for composite materials and the need is felt for deepening the knowledge on the mechanisms governing the chip formation and the tool wear development.

Agent Control Technology for Multi-Robot Systems

yet unknown — Wed, 27 Jun 2007 15:57:57 +0000

Nowadays, Multi-Robot Systems (MRS) control represents a great challenge in the research community: the interest in MRS is justified by the numerous advantages that a group of autonomous robots offers compared to a single robot, in particular when complex missions are assigned. However, these systems need a complex control architecture and a method of coordination of the autonomous robots. In this paper, a Multi-Agent System (MAS) based approach is proposed to solve this problem: the purpose is to realize a decentralized system, where each robot, using a Reinforcement Learning (RL) mechanism, autonomously acquires the appropriate behaviour and suitable rules through its experience of interaction with the environment and the other robots.

A complex geometry carried out from steel sheets by incremental forming

Antonio Formisano — Wed, 27 Jun 2007 15:57:57 +0000

Incremental forming is a process that can satisfy the most disparate requirements in terms of feasible geometries; in other words it is possible to affirm that it is a very flexible process. Moreover, the high formability of sheets for the process under examination, allows to get considerable drawability levels.

The aim of the present paper has been the evaluation of the formability of steel sheets and the achievement of complex geometries by means of incremental forming process. The paper shows how it is possible to use a FE code, previously validated for forming processes, to evaluate the forming limit curves of the steels.

MACHINING ERRORS IN TURNING OF A MULTI-DIAMETER WORKPIECE

Prisco — Wed, 27 Jun 2007 15:57:57 +0000

The present work shows a model to evaluate machining accuracy in turning of a multi-diameter bar. The proposed model has been applied to the most common turning schemes related to workpiece fixturing. Some numerical examples have been computed using the proposed model to predict the diameter error along the workpiece and the cutting force along the workpiece axis. The results provide additional insight into the error formation in the turning process. The proposed model represents a first step towards the accuracy control in turning operation of complex shape parts and, then, towards the optimi

Kohonen Maps for Chip Form Classification in Turning

Doriana — Wed, 27 Jun 2007 15:57:56 +0000

Chip form classification during longitudinal turning of carbon steel with coated carbide inserts, yielding different chip forms, was performed using cutting force sensor signals. Advanced signal analysis was carried out by spectral estimation through a parametric method. In this approach, the signal spectrum is assumed to take on a specific functional form, the parameters of which are unknown. The spectral estimation problem becomes one of estimating the unknown parameters of the spectrum model, rather than the spectrum itself. From the cutting force signal, a set of features, corresponding to the characteristic parameters of the spectrum model, were obtained by linear predictive analysis.