scholarly journals Cumulative Inaccuracies in Implementation of Additive Manufacturing Through Medical Imaging, 3D Thresholding, and 3D Modeling: A Case Study for an End-Use Implant

2020 ◽  
Vol 10 (8) ◽  
pp. 2968 ◽  
Author(s):  
Jan Sher Akmal ◽  
Mika Salmi ◽  
Björn Hemming ◽  
Linus Teir ◽  
Anni Suomalainen ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Additive Manufacturing ◽  
Medical Imaging ◽  
3D Modeling ◽  
Computer Aided Design ◽  
Digital Design ◽  
Worst Case ◽  
Custom Made ◽  
End Use

In craniomaxillofacial surgical procedures, an emerging practice adopts the preoperative virtual planning that uses medical imaging (computed tomography), 3D thresholding (segmentation), 3D modeling (digital design), and additive manufacturing (3D printing) for the procurement of an end-use implant. The objective of this case study was to evaluate the cumulative spatial inaccuracies arising from each step of the process chain when various computed tomography protocols and thresholding values were independently changed. A custom-made quality assurance instrument (Phantom) was used to evaluate the medical imaging error. A sus domesticus (domestic pig) head was analyzed to determine the 3D thresholding error. The 3D modeling error was estimated from the computer-aided design software. Finally, the end-use implant was used to evaluate the additive manufacturing error. The results were verified using accurate measurement instruments and techniques. A worst-case cumulative error of 1.7 mm (3.0%) was estimated for one boundary condition and 2.3 mm (4.1%) for two boundary conditions considering the maximum length (56.9 mm) of the end-use implant. Uncertainty from the clinical imaging to the end-use implant was 0.8 mm (1.4%). This study helps practitioners establish and corroborate surgical practices that are within the bounds of an appropriate accuracy for clinical treatment and restoration.

Redesigning a Reaction Control Thruster for Metal-Based Additive Manufacturing: A Case Study in Design for Additive Manufacturing

2016 ◽  
Author(s):  
Matthew R. Woods ◽  
Nicholas A. Meisel ◽  
Timothy W. Simpson ◽  
Corey J. Dickman
Keyword(s):  
Additive Manufacturing ◽  
Attitude Control ◽  
Development Effort ◽  
Design For Additive Manufacturing ◽  
Powder Bed ◽  
Subtractive Manufacturing ◽  
End Use ◽  
Manufacturing Time ◽  
Novel Design

Prior research has shown that powder bed fusion additive manufacturing (AM) can be used to make functional, end-use components from powdered metallic alloys, such as Inconel® 718 super alloy. However, these end-use products are often based on designs developed for more traditional subtractive manufacturing processes without taking advantage of the unique design freedoms afforded by AM. In this paper, we present a case study involving the redesign of NASA’s existing “Pencil” thruster used for spacecraft attitude control. The initial “Pencil” thruster was designed for, and manufactured using, traditional subtractive methods. The main focus in this paper is to (a) review the Design for Additive Manufacturing (DfAM) concepts and considerations used in redesigning the thruster and (b) compare it with a parallel development effort redesigning the original thruster to be manufactured more effectively using subtractive processes. The results from this study show how developing end-use AM components using DfAM guidelines can significantly reduce manufacturing time and costs while introducing new and novel design geometries.

Design Innovation With Additive Manufacturing: A Methodology

2019 ◽  
Author(s):  
K. Blake Perez ◽  
Carlye A. Lauff ◽  
Bradley A. Camburn ◽  
Kristin L. Wood
Keyword(s):  
Additive Manufacturing ◽  
Design Process ◽  
Business Models ◽  
Engineering Product ◽  
Process Framework ◽  
New Business ◽  
Design Innovation ◽  
End Use ◽  
New Business Models

Abstract Additive manufacturing (AM) has matured rapidly in the past decade and has made significant progress towards a reliable and repeatable manufacturing process. The technology opens the doors for new types of innovation in engineering product development. However, there exists a need for a design process framework to efficiently and effectively explore these newly enabled design spaces. Significant work has been done to understand how to make existing products and components additively manufacturable, yet there still exists an opportunity to understand how AM can be leveraged from the very outset of the design process. Beyond end use products, AM-enabled opportunities include an enhanced design process using AM, new business models enabled by AM, and the production of new AM technologies. In this work, we propose the use, adaptation and evolution of the SUTD-MIT International Design Centre’s Design Innovation (DI) framework to assist organizations effectively explore all of these AM opportunities in an efficient and guided manner. We build on prior work that extracted and formalized design principles for AM. This paper discusses the creation and adaptation of the Design Innovation with Additive Manufacturing (DIwAM) methodology, through the combination of these principles and methods under the DI framework to better identify and realize new innovations enabled by AM. The paper concludes with a representative case study with industry that employs the DIwAM framework and the outcomes of that project. Future studies will analyze the effects that DIwAM has on designers, projects, and solutions.

PROSTHETIC EAR RECONSTRUCTION APPLYING COMPUTER TOMOGRAPHIC (CT) DATA AND ADDITIVE MANUFACTURING TECHNOLOGIES

2015 ◽  
Vol 76 (7) ◽  
Author(s):  
Nor Azura Mohamed ◽  
Zainul Ahmad Rajion
Keyword(s):  
Additive Manufacturing ◽  
Medical Imaging ◽  
Computer Aided Design ◽  
Physical Models ◽  
Ear Reconstruction ◽  
New Approach ◽  
Imaging Technology ◽  
Wax Pattern ◽  
Computer Aided ◽  
Aided Design

The treatment of auricle defect can be by surgical or prosthetic ear rehabilitation depending on the condition.  Current practice by surgeon for prosthetic ear rehabilitation require patient to go for osseointegrated craniofacial implant surgery for retention of the prosthetic ear.  Impression technique play a vital role in accurate reproduction of affected and unaffected ears, orientation of the ear during wax try in and fabrication of ear prostheses. Traditionally, the wax pattern was created from the impression taken from patient and the final prosthesis is processed with silicone material.  This conventional method has always been time consuming, massive work and caused discomfort to patient.  Moreover the accuracy of the final prosthetic sometimes was not satisfied. Improvement in medical imaging technology whereby data from computerized tomography (CT) in 2D format can be converting to 3 dimensional images gave tremendous view for surgeon to visualize the result.  A new and impressive advance in the development of additive manufacturing technology is now being able to be applied in medical field.  The widespread use of computer-aided design (CAD) combine with computer aided manufacturing (CAM) produced the momentum and desire to translate the 3-D images into physical models. Studies and research have indicated the viability of using medical imaging technology, computer aided design (CAD) and additive manufacturing techniques in prosthetics.  This paper proposed a novel method of fabricating the prosthetic ear applying mirror image technique to reconstruct the missing ear, and then fabricate the 3D model of the prosthetic ear using Stereolitography (SLA) technology that will become the master mold to produce the final prosthetic ear.  This method eliminates the traditional wax pattern procedure. A clinical study is done onto a patient in HUSM and comparison is made between traditional method vs new approach using computer aided technology.  Result showed that there is significant different between traditional and new approach design.  The new method also shows time reduction during design and fabrication stage.  

A Novel Model for the Tolerancing of Nonrigid Part Assemblies in Computer Aided Design

2019 ◽  
Vol 19 (4) ◽  
Author(s):  
Mehdi Tlija ◽  
Anis Korbi ◽  
Borhen Louhichi ◽  
Abdelmajid Benamara
Keyword(s):  
Computer Aided Design ◽  
Tolerance Analysis ◽  
Physical Factors ◽  
Worst Case ◽  
Manufacturing Defects ◽  
Computer Aided ◽  
Aided Design ◽  
Novel Model

In the design step, the realistic modeling of the product represents an industrial requirement and a digital muck up (DMU) improvement. Thus, the tolerance integration in the computer aided design (CAD) model with the neglect of important physical factors, such as the components’ deformations during the mounting and assembly operation, causes a deviation between the numerical and the realistic models. In this regard, this paper presents a new model for the tolerance analysis of CAD assemblies based on the consideration of both manufacturing defects and deformations. The dimensional and geometrical tolerances are considered by the determination of assemblies’ configurations with defects based on the worst case tolerancing. The finite elements (FEs) simulation is realized with realistic models. An algorithm for updating the realistic mating constraints, between rigid and nonrigid parts, is developed. The case study of an assembly with planar and cylindrical joints is presented.

scholarly journals Modeling and Additive Manufacturing of a Missing Teeth Human Mandible

2019 ◽  
Vol 8 (6S2) ◽  
pp. 1071-1075
Keyword(s):  
Computed Tomography ◽  
Additive Manufacturing ◽  
Computer Aided Design ◽  
3D Model ◽  
Research Work ◽  
3D Structure ◽  
Biological Model ◽  
Fiber Reinforced Polymers ◽  
Cad Model ◽  
Fused Deposition

In biomedical engineering, fiber-reinforced polymers play an important role in creating physical biological models of patients, which helps surgeons explain anatomical details to patients and perform trial operations. Replicating the precise three-dimensional (3D) structure of the human mandible is now a priority for rebuilding these bones for complete functional and aesthetic healing. Additional production methods and reverse engineering are required to achieve the design of a personalized device with precise shape and size. The main purpose of this research work is to develop a specially developed human mandibular biological model using the additive manufacturing method, FDM (Fused Deposition Melting). FDM is performed by loading a CAD model into a 3D Printer. We present this method using the FDM (Fused Deposition Melting) method to generate a human mandible biological model. Data obtained from computed tomography (CT) with a resolution of 1 mm was converted to a 3D model by computer aided design (CAD) using CT digital imaging and medical communication (DICOM) data. After the CAD model is built, it is converted to a stereolithography (*.STL) format and then processed by rapid prototyping techniques to create a physical anatomical model using 3D printing. Converting two-dimensional data (2D) from computed tomography data to a 3D model is an accurate guide to shaping bone grafts. The current approach can translate treatment plans directly into the surgical field. It is an important teaching tool for forming and fixing implants, helping to counsel patients.

Redesigning a Reaction Control Thruster for Metal-Based Additive Manufacturing: A Case Study in Design for Additive Manufacturing

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Nicholas A. Meisel ◽  
Matthew R. Woods ◽  
Timothy W. Simpson ◽  
Corey J. Dickman
Keyword(s):  
Additive Manufacturing ◽  
Attitude Control ◽  
Manufacturing Processes ◽  
Development Effort ◽  
Design For Additive Manufacturing ◽  
Powder Bed ◽  
Subtractive Manufacturing ◽  
End Use ◽  
Manufacturing Time

Prior research has shown that powder-bed fusion (PBF) additive manufacturing (AM) can be used to make functional, end-use components from powdered metallic alloys, such as Inconel® 718 superalloy. However, these end-use components and products are often based on designs developed for more traditional subtractive manufacturing processes and do not take advantage of the unique design freedoms afforded by AM. In this paper, we present a case study involving the redesign of NASA’s existing “pencil” thruster used for spacecraft attitude control. The initial pencil thruster was designed for and manufactured using traditional subtractive methods. The main focus in this paper is to (a) identify the need for and use of both opportunistic and restrictive design for additive manufacturing (DfAM) concepts and considerations in redesigning the thruster for fabrication with PBF AM and (b) compare the resulting DfAM thruster with a parallel development effort redesigning the original thruster to be manufactured more effectively using subtractive manufacturing processes. The results from this case study show how developing end-use AM components using specific DfAM guidelines can significantly reduce manufacturing time and costs while enabling new and novel design geometries.

Development of 3D-printed customized facial padding for burn patients

2019 ◽  
Vol 25 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Muhammad Aiman Ahmad Fozi ◽  
Mohamed Najib Salleh ◽  
Khairul Azwan Ismail
Keyword(s):  
Additive Manufacturing ◽  
3D Printing ◽  
Computer Aided Design ◽  
Digital Design ◽  
Pressure Measurements ◽  
Pressure Therapy ◽  
Content Type ◽  
Manufacturing Method ◽  
Pressure Region ◽  
3D Printed

Purpose This paper aims to develop 3D-printed customized padding to increase pressure at the zero pressure region. This padding is specifically intended for facial areas with complex contours in pressure therapy treatment of hypertrophic scars. Design/methodology/approach To carry out this study, a full-face head garment was fabricated by a local occupational therapist, and pressure measurements were conducted to establish the pressure exerted by this head garment and to determine the zero pressure region. Furthermore, an additional manufacturing method was used to construct customized padding, and pressure measurements were performed to measure the pressure exerted after application of this customized padding. Findings The results reveal that 3D-printed customized padding can increase pressure at the zero pressure region, which occurs on complex contour surfaces with a spatial gap because of non-contact of the head garment and facial surfaces. Practical implications This paper suggests that an additive manufacturing method using 3D printing is capable of producing accurate, functional and low-cost medical parts for rehabilitation. Moreover, the 3D-printed padding fabricated by additive manufacturing assists in generating optimal pressure, which is necessary for effective pressure therapy. Originality/value Digital design using 3D scanning, computer-aided design and 3D printing is capable of designing and producing properly fitting, customized padding that functions to increase pressure from zero to an acceptable pressure range required for pressure therapy.

Regeneration von Knochendefekten mit computergesteuerter Herstellung von Gerüstträgern

2013 ◽  
Vol 22 (03) ◽  
pp. 180-187 ◽  
Author(s):  
J. Henke ◽  
J. T. Schantz ◽  
D. W. Hutmacher
Keyword(s):  
Tissue Engineering ◽  
Additive Manufacturing ◽  
Custom Made

ZusammenfassungDie Behandlung ausgedehnter Knochen-defekte nach Traumata oder durch Tumoren stellt nach wie vor eine signifikante Heraus-forderung im klinischen Alltag dar. Aufgrund der bestehenden Limitationen aktueller Therapiestandards haben Knochen-Tissue-Engineering (TE)-Verfahren zunehmend an Bedeutung gewonnen. Die Entwicklung von Additive-Manufacturing (AM)-Verfahren hat dabei eine grundlegende Innovation ausgelöst: Durch AM lassen sich dreidimensionale Gerüstträger in einem computergestützten Schichtfür-Schicht-Verfahren aus digitalen 3D-Vorlagen erstellen. Wurden mittels AM zunächst nur Modelle zur haptischen Darstellung knöcherner Pathologika und zur Planung von Operationen hergestellt, so ist es mit der Entwicklung nun möglich, detaillierte Scaffoldstrukturen zur Tissue-Engineering-Anwendung im Knochen zu fabrizieren. Die umfassende Kontrolle der internen Scaffoldstruktur und der äußeren Scaffoldmaße erlaubt eine Custom-made-Anwendung mit auf den individuellen Knochendefekt und die entsprechenden (mechanischen etc.) Anforderungen abgestimmten Konstrukten. Ein zukünftiges Feld ist das automatisierte ultrastrukturelle Design von TE-Konstrukten aus Scaffold-Biomaterialien in Kombination mit lebenden Zellen und biologisch aktiven Wachstumsfaktoren zur Nachbildung natürlicher (knöcherner) Organstrukturen.

Sign in / Sign up

Export Citation Format

Share Document