Process-Planning for Layered Manufacturing of Heterogeneous Objects Using Direct Metal Deposition

2002 ◽  
Vol 2 (4) ◽  
pp. 330-344 ◽  
Author(s):  
Ki-Hoon Shin ◽  
Debasish Dutta
Keyword(s):  
Process Planning ◽  
Tool Path ◽  
Three Dimensional ◽  
Layered Manufacturing ◽  
Pattern Generation ◽  
Adaptive Slicing ◽  
Heterogeneous Objects ◽  
Build Time ◽  
Material Information ◽  
Discretization Process

Layered manufacturing (LM) is emerging as a new technology that enables the fabrication of three-dimensional heterogeneous objects such as multimaterials and functionally gradient materials (FGMs). The necessary steps for LM fabrication of heterogeneous objects include representation and process planning of material information inside an object. This paper introduces a new processing planning method that takes into account the processing of material information. The detailed tasks are pre-processing (discretization), orientation (build direction selection), and adaptive slicing of heterogeneous objects. In particular, this paper focuses on the discretization process that converts all of the material information inside a heterogeneous object into material features like geometric features. It is thus possible to choose an optimal build direction among various preselected ones by approximately estimating build time. This is because total build time depends on the complexity of features. This discretization process also allows adaptive slicing of heterogeneous objects to minimize surface finish and material composition error. In addition, tool path planning can be simplified into fill pattern generation. Examples are shown to illustrate the overall procedure.

Pre-Processing of Heterogeneous Objects for Layered Manufacturing

2001 ◽  
Author(s):  
Ki-Hoon Shin ◽  
Debasish Dutta
Keyword(s):  
Tool Path ◽  
New Technology ◽  
Three Dimensional ◽  
Layered Manufacturing ◽  
Pattern Generation ◽  
Geometric Features ◽  
Adaptive Slicing ◽  
Heterogeneous Objects ◽  
Build Time ◽  
Material Information

Abstract Layered manufacturing (LM) is emerging as a new technology that enables fabrication of three dimensional heterogeneous objects (such as Multi-materials and Functionally Gradient Materials). The steps for fabricating heterogeneous objects include model representation and material process planning. This paper introduces a method for processing the material information. It includes pre-processing (discretization), orientation (build direction selection), and adaptive slicing of heterogeneous objects. The discretization process converts all material information inside a heterogeneous object to material features like geometric features, thus it makes it possible to determine build direction by estimating build time based on geometric features and material features. It also allows adaptive slicing of heterogeneous objects to minimize surface finish and material resolution error. In addition, tool path planning can be simplified to fill pattern generation. Examples are shown.

Adaptive Slicing of Heterogeneous Solid Models for Layered Manufacturing

1998 ◽  
Author(s):  
Vinod Kumar ◽  
Prashant Kulkarni ◽  
Debasish Dutta
Keyword(s):  
Process Planning ◽  
Layered Manufacturing ◽  
Functionally Graded ◽  
Adaptive Slicing ◽  
Heterogeneous Objects ◽  
Solid Models ◽  
Fundamental Process ◽  
Planning Task ◽  
Material Information ◽  
Heterogeneous Solid

Abstract A novel feature of Layered Manufacturing, an emerging manufacturing technology, is that it enables fabrication of heterogeneous objects (multi-material and functionally graded interiors). In our earlier work, we developed new modeling schemes (called heterogeneous solid models) for representing these heterogeneous objects by capturing both geometry and material information. One of the crucial steps for fabricating these heterogeneous objects in LM is adaptive slicing, a fundamental process planning task. In this paper, we describe how the heterogeneous solid models can be adaptively sliced to aid in the LM fabrication of heterogeneous objects.

Increasing Part Accuracy in Additive Manufacturing Processes Using a k-d Tree Based Clustered Adaptive Layering

2014 ◽  
Vol 136 (6) ◽  
Author(s):  
Neeraj Panhalkar ◽  
Ratnadeep Paul ◽  
Sam Anand
Keyword(s):  
Additive Manufacturing ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
Layer By Layer ◽  
Adaptive Slicing ◽  
Stl File ◽  
Build Time ◽  
Standard File Format ◽  
Aided Design ◽  
Profile Errors

Additive manufacturing (AM) is widely used in aerospace, automobile, and medical industries for building highly accurate parts using a layer by layer approach. The stereolithography (STL) file is the standard file format used in AM machines and approximates the three-dimensional (3D) model of parts using planar triangles. However, as the STL file is an approximation of the actual computer aided design (CAD) surface, the geometric errors in the final manufactured parts are pronounced, particularly in those parts with highly curved surfaces. If the part is built with the minimum uniform layer thickness allowed by the AM machine, the manufactured part will typically have the best quality, but this will also result in a considerable increase in build time. Therefore, as a compromise, the part can be built with variable layer thicknesses, i.e., using an adaptive layering technique, which will reduce the part build time while still reducing the part errors and satisfying the geometric tolerance callouts on the part. This paper describes a new approach of determining the variable slices using a 3D k-d tree method. The paper validates the proposed k-d tree based adaptive layering approach for three test parts and documents the results by comparing the volumetric, cylindricity, sphericity, and profile errors obtained from this approach with those obtained using a uniform slicing method. Since current AM machines are incapable of handling adaptive slicing approach directly, a “pseudo” grouped adaptive layering approach is also proposed here. This “clustered slicing” technique will enable the fabrication of a part in bands of varying slice thicknesses with each band having clusters of uniform slice thicknesses. The proposed k-d tree based adaptive slicing approach along with clustered slicing has been validated with simulations of the test parts of different shapes.

On the Application of Tensor Product Solids in Heterogeneous Solid Modeling

1998 ◽  
Author(s):  
Anne Marsan ◽  
Debasish Dutta
Keyword(s):  
Tensor Product ◽  
Process Planning ◽  
Material Properties ◽  
Model Material ◽  
Layered Manufacturing ◽  
Solid Model ◽  
Heterogeneous Objects ◽  
Solid Models ◽  
Multiple Materials ◽  
Heterogeneous Solid

Abstract With the development of layered manufacturing (LM) technologies, engineers are now able to build objects which are composed of multiple materials and/or have varying material properties throughout. These so called heterogeneous objects can be described by heterogeneous solid models, which contain information about the boundaries of the object, as well as material properties. In this paper we show how tensor product solids, which are the 3D extension of tensor product surfaces, can be used to model material properties within the framework of a heterogeneous solid model. We then show how a heterogeneous solid model which makes use of tensor product solids can be used in reverse engineering and process planning for LM.

A Generic Tool Path Generation Methodology for Incremental Forming

2008 ◽  
Author(s):  
Rajiv Malhotra ◽  
N. Venkata Reddy ◽  
Jian Cao
Keyword(s):  
Tool Path ◽  
Incremental Forming ◽  
Single Point ◽  
Tool Path Generation ◽  
Layered Manufacturing ◽  
Path Generation ◽  
Single Point Incremental Forming ◽  
Adaptive Slicing ◽  
Geometrical Accuracy ◽  
Arbitrary Component

This paper presents a generic methodology for tool path generation for an arbitrary component that can be formed by single point incremental forming (SPIF) to obtain required geometrical accuracy. Adaptive slicing concepts used in layered manufacturing have been modified and used for generating tool path for SPIF. Experiments and FEA have been carried out to study the effectiveness of the proposed methodology. Results indicate that the proposed methodology enhances the accuracy achievable in SPIF.

Automated Slicing for a Multiaxis Metal Deposition System

2006 ◽  
Vol 129 (2) ◽  
pp. 303-310 ◽  
Author(s):  
Jianzhong Ruan ◽  
Todd E. Sparks ◽  
Ajay Panackal ◽  
F. W. Liou ◽  
Kunnayut Eiamsa-ard ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Surface Quality ◽  
Medial Axis ◽  
Three Dimensional ◽  
Metal Deposition ◽  
Layered Manufacturing ◽  
Analysis Tool ◽  
Topological Information ◽  
Adaptive Slicing ◽  
Potential Problems

A multiaxis adaptive slicing algorithm for multiaxis layered manufacturing, which can generate optimal slices to achieve deposition without support structures, is presented in this paper. Different from current adaptive slicing, this technique varies not only layer thickness but also in slicing/building direction. Aware of potential problems of previous research on slicing, the work in this paper focuses on innovative geometry reasoning and analysis tool-centroidal axis. Similar to medial axis, it contains geometry and topological information but is significantly computationally cheaper. Using a centroidal axis as a guide, the multiaxis slicing procedure is able to generate a three-dimensional layer or change slicing direction as needed automatically to build the part with better surface quality. This paper presents various examples to demonstrate the feasibility and advantages of centroidal axis and its usage in the multiaxis slicing process.

Layered Manufacturing: Current Status and Future Trends

2000 ◽  
Vol 1 (1) ◽  
pp. 60-71 ◽  
Author(s):  
Debasish Dutta ◽  
Fritz B. Prinz ◽  
David Rosen ◽  
Lee Weiss
Keyword(s):  
Process Planning ◽  
Layered Manufacturing ◽  
Current Status ◽  
Manufacturing Processes ◽  
Future Trends ◽  
Planning Techniques ◽  
Current Technology ◽  
Heterogeneous Objects ◽  
The Future ◽  
Design Systems

This paper reviews the emerging field of layered manufacturing. This field is little over 10 years old but a significant amount of research has been conducted and results to date are quite promising. We consider three broad topics namely, design systems for heterogeneous objects, layered manufacturing processes, and process planning techniques. Several applications/examples are included in the course of the survey and limitations of current technology identified. We conclude with some possibilities for the future.

An Approach to Modeling & Representation of Heterogeneous Objects

1998 ◽  
Vol 120 (4) ◽  
pp. 659-667 ◽  
Author(s):  
V. Kumar ◽  
D. Dutta
Keyword(s):  
Layered Manufacturing ◽  
Solid Model ◽  
Cad Model ◽  
Geometric Information ◽  
Heterogeneous Objects ◽  
Modeling Techniques ◽  
Heterogeneous Models ◽  
Computer Representation ◽  
Modeling Representation ◽  
Material Information

Heterogeneous objects, composed of different materials, are increasingly being used in engineering applications. Also, a new fabrication method called Layered Manufacturing (LM) has shown potential to manufacture these objects. In order to manufacture heterogeneous objects by LM, a CAD model is required that contains both geometry and material information. However, current solid modeling techniques focus on capturing the geometric information only. In this paper, we present an approach to model and represent heterogeneous objects by integrating the material information along with the geometry/topology in the solid model. We define new modeling operations for creating and manipulating heterogeneous models and to complement traditional modeling operations. We also address the issue of computer representation of these new models. Finally, the issue of fabrication of these heterogeneous objects by LM is discussed.

Diagnostic System of Gravitational Solid Flow Based on Weight and Accelerometer Signal Analysis Using Wireless Data Transmission Technology

2012 ◽  
Vol 17 (4) ◽  
pp. 319-326 ◽  
Author(s):  
Zbigniew Chaniecki ◽  
Krzysztof Grudzień ◽  
Tomasz Jaworski ◽  
Grzegorz Rybak ◽  
Andrzej Romanowski ◽  
...  
Keyword(s):  
Signal Analysis ◽  
Scale Up ◽  
Three Dimensional ◽  
Diagnostic System ◽  
Wireless Data ◽  
Stick Slip ◽  
Wireless Data Transmission ◽  
Accelerometer Signal ◽  
Flow Investigation ◽  
Material Information

Abstract The paper presents results of the scale-up silo flow investigation in based on accelerometer signal analysis and Wi-Fi transmission, performed in distributed laboratory environment. Prepared, by the authors, a set of 8 accelerometers allows to measure a three-dimensional acceleration vector. The accelerometers were located outside silo, on its perimeter. The accelerometers signal changes allowed to analyze dynamic behavior of solid (vibrations/pulsations) at silo wall during discharging process. These dynamic effects are caused by stick-slip friction between the wall and the granular material. Information about the material pulsations and vibrations is crucial for monitoring the interaction between silo construction and particle during flow. Additionally such spatial position of accelerometers sensor allowed to collect information about nonsymmetrical flow inside silo.

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