SFF technologies have an ability of creating a physical part directly .•. from its computer model by. adding material on a layer by layer basis. One of the problems lies in their current file fonnat for CAD data exchange. Current method using the de facto industry standard STL have at times resulted in problems such< as accuracy, redundancy, and integrity in its representing CAD models. In this...

Lost-foam (also known as Expendable Pattern Casting, EPC) is an ever-growing metal casting technique, capable of producing complex metal components without parting lines. Mold preparation for lost-foam casting is typically accurate, but expensive and slow. The goal of this research was to develop a new approach for producing rapid lost-foam molds. With this new approach, patterns generated by S...

In the paper there are presented the results of the analysis of the quality of UWB pulse transmission in the channel containing convex obstacle. The convex ovstacle is a cylinder, which is widely used in simulation tools as a model of the human, whose presence in UWB channel have to be taken into consideration. The analysis are made with the usage of measurement results. The measurements were p...

The orientation of SFF-manufactured parts can have a signiicant eeect on the quality of the parts, in both surface eeects and strength. Currently, orientation is either ignored or set on the basis of experience. This paper takes some simple experiments and creates quantitative measures relating diierent aspects of part quality to orientation. This leads to several computational tools for optimi...

This paper presents a solid freeform fabrication (SFF) technique based on micro-plasma powder deposition (MPPD). The relationship between the geometric features of the deposited layers and the welding parameters is investigated. The arc length is controlled through the monitoring of the arc voltage. The result of building parts with functionally graded components by the MPPD process is shown as...

This article addresses the central impediment to the wide-spread exploration of the potential of Local Composition Control (LCC) in Solid Freeform Fabrication (SFF), and presents a Feature-Based Design (FBD) approach for modeling complex components with LCC. The approach will allow the designer to simultaneously edit geometry and composition until a satisfactory result is attained. The concise ...

Demands for increased Solid Freeform Fabrication precision and speed suggest the need for advanced scanning techniques, such as boundary tracing, half-lap and multiple orientation scanning, or ÔintelligentÕ scanning. Since most SFF processes construct parts from parallel material layers, separating model slicing and scan conversion functions appears to be a powerful approach. Both can benefit f...