308. Design for Automation: The Rapid Fixture Approach
RWTH Aachen, Germany
As product varieties rise and lifecycles shorten, development approaches need to be adapted. Current trends aiming to solve the dissonance of reduced time to market and increased product variety include agile methods. In this context not only product design processes need to be adapted but also development of production processes and manufacturing equipment. At the example of fixture design, this paper presents an approach which allows an agile provision as well as a reconfiguration of equipment. The solution presented consists of a fixture design concept consisting of design rules which allow implementation into a tool for automated fixture design.
140. Print-in-Place of Interconnected Deformable and Rigid Parts of Articulated Systems
1Dipartimento di Meccanica – Politecnico di Milano, Milano I-20156, Italy; 2Graduated Student, Politecnico di Milano, Milano I-20156, Italy
In spite of the initial enthusiasms, as the experience in this field grows, it is becoming more and more evident that adopting an Additive Manufacturing (AM) process is advantageous only in those situations where its peculiarities can be fully exploited in order to realize “something” that cannot be realized otherwise and/or to shorten and/or simplify a production cycle.
In this perspective, this paper presents two case studies where two of the most “fascinating” and peculiar capabilities of the AM techniques are exploited to further improve two systems already manufactured with an AM (Fused Deposition Modelling - FDM) technique.
The Print in Place (PiP) and the Multi-Material Deposition (MMD) capabilities have been deployed to produce a stable junction between rigid (Poly-Lactic Acid, PLA) and flexible (Thermoplastic polyurethane, TPU) materials in order to realize hinges without any assembly operation. The development of such a junction is not trivial, since PLA and TPU do not adhere because of the chemical and/or thermal bonds that may generate during the FDM deposition process. Actually, their adhesion is usually unwanted because PLA is typically used to create the supporting structures of TPU objects. Therefore, a specific geometry has been created to guarantee a proper and durable junction.
More in detail, this solution has been used to develop two types of end effectors: an adaptive robotic grip, based on the fin-ray effect, and a flexible hand, based on the well-known and wide spread “flexi-hands”.
At a glance, each finger of the adaptive robotic grip is made of a triangular deformable structure, two edges of which are connected by means of rigid rods. Usually these rods are manufactured separately and then mounted on the triangular deformable structure. The developed junction allows for printing the rigid rods together with the deformable structure.
For what concerns the second case study, i.e. the flexible hands, two manufacturing solutions exist. The first and simpler method consists in manufacturing it as a single TPU flexible part. The second approach consists in printing several parts (phalanxes, palm and deformable junction elements), which have then to be assembled. The developed junction allows for creating and assembling all these parts in a single process.
As a conclusion, this paper presents two practical applications of an innovative solution for joining rigid and deformable materials, in order to develop articulated systems in a single operation.
245. Impact of Merging Components by Additive Manufacturing in Spare Parts Management
University of Brescia, Italy
Purpose – As manufacturers and researchers continuously look for more appealing approaches towards improved applications and better integration of machinery based on Additive Manufacturing (AM) technologies in different fields of industry, spare parts sector has been demonstrating more promising signs of progress for further implementation of AM. One of these signs lies within merging components of maintenance spare parts. From an operational point of view, with AM-in contrast to conventional methods of production-functionality comes before and above complexity of the design, and thus, manufacturing functionally enhanced parts characterized by the least possible number of assemblies whose design complexities can be matched with customers’ desired requirements becomes more feasible and accessible. From a strategic point of view, the just-in-time nature of AM-based productions eliminates the need for having large warehouses which are always accompanied with resource demanding inventory keeping practices.
The purpose of this paper is to investigate how consolidation of spare parts through reduction of their sub-assemblies can be influenced as an additive technology is used for production of various components that make up the final part composition.
Design/methodology/approach – The approach is based on parametric analysis of the main factors that influence the total incurred cost resulting from acquisition and management of the spare parts. These are the spares which are used to maintain and repair the parts that are used in the final product. A plausible classification of these factors is done to account for both the manufacturing method, and the product structure itself. While the primary set of factors include effects of production cost, reliability effects, and logistics cost to account for the manufacturing method, the secondary set of factors include cost and reliability distribution of the components to incorporate the product specific features in the study.
This process is performed by considering a base structure for the part composition and inclusion of final components which are produced with the current conventional methods (as-is), and then comparing this with an established list of all possible alternatives that include merger of components produced by an AM technology (to-be).
Findings – The sensitivity analysis in this study demonstrates the factors and their combinations that mainly affect the total incurred cost.
Value/Originality – This study provides an evaluation of all alternatives through an enumeration process. In the meantime, a further and in-depth investigation of maintenance and repair implications resulting from AM usage in spare parts industry is provided in order to identify the associated cons and pros.
Research limitations/implications – The main implication of this study is to understand how changing methods of production from a conventional process to an additive one for a multi-component product composition could alter the use-phase of components in medium to long terms. This can be a building block to perform a more comprehensive and extensive future research to include more sophisticated product structure and logistics for analysis of spare parts consolidation.
133. The Role of Additive Manufacturing in the Era of Industry 4.0
Middle East Technical University, Turkey
The fourth industrial revolution, namely Industry 4.0, is the recent movement on intelligent automation technology. It offers cyber and physical systems to cooperate profitably, aiming to build smart factories. Additive manufacturing (AM) is one of the vital issues in the Industry 4.0, in which physical and digital world will be integrated together. Due to the essentiality of customization in Industry 4.0, superior manufacturing methods over the conventional ones are needed to be developed. AM plays an important role in manufacturing customized/personalized products by its ability to create sophisticated objects with several materials. In this new era, utilization of 3D printing technology may turn any computer into a small factory.
Currently, the AM is being used in various industries, such as aerospace, biomedical, casting etc., along with an increase in the number of customized products. Although there are still some doubts about its applicability in mass production, availability of additive manufacturing in the industry rises with the new developments. Being a developing technology to create accurate and strengthened complex objects with increased manufacturing speed, AM may offer a way of replacing the old manufacturing techniques in the future.
In this paper, a comprehensive review on additive manufacturing technologies is investigated in relation with Industry 4.0. The main objective of this review paper is to classify the novel knowledge on AM technology for the researchers and highlight its potential and future trends.
This review mainly focuses on three important subjects about additive manufacturing: recent advances on material science, process development for AM, and enhancements on design computations. Researchers have shown an increasing interest in material studies due to its direct relation with the applicability of AM in the industry. To create the object with improved characteristics, various materials have been examined including smart materials and multi-material printing. Recently proposed AM processes, especially the ones developed for various environmental conditions, are also to be discussed in this paper. Additionally, studies regarding the development on computational tools of design are to be surveyed as another trending topic in the field. Several examples will be presented to understand the role of AM in Industry 4.0.
70. A New Method for Generating Image Projections in DLP-type 3D Printer Systems
Middle East Technical University, Turkey
This paper presents a novel method for generating image projections required for Digital Light Processing (DLP) type 3D printer systems where the entire cross-section of the printed object is directly formed via projecting the image onto a vat of photopolymers. The main difference of DLP printers from the printers utilizing stereolithography (SLA) technique is that it uses conventional type of projectors to reflect the sliced parts onto the window of the vat. In SLA systems, one or more laser heads are required to scan the whole slice and it takes much longer for SLA to fabricate the same object. Considering the details of the proposed method, the cross-sections (i.e. slices) of the solid model to be printed are obtained with the given tolerance parameters. The cross-sections, which are initially represented as bitmap images, are then processed along particular directions to characterize the given features efficiently. Once the tree structure associated with a cross-section is attained, the data for each- and every slice are compressed via a novel lossless compression technique titled DY16 which makes good use of relative data encoding. The coherence between the consecutive slices (or images) are taken into account in this proposed paradigm. Apart from this new method, the performances of the different compression algorithms (such as Huffman coding, Arithmetic coding, LZW, run length encoding, JPEG 2000) are also evaluated through two test cases (e.g. Stanford Bunny and Helical Gear) having completely different topologies. The paper shows that the DY16 technique, which is suitable for fast real-time hardware implementation, yields satisfactory performance in terms of data compaction achieved in the test cases considered. The presented method is realized on Python computing platform whose hardware implementation could be conveniently carried out on small form-factor computers armed with powerful multi-kernel microprocessors / microcontrollers. In this case, there would be no need to transfer each slice (image) to the 3D printer. The compact code would be enough to fabricate the corresponding 3D part right on the 3D printer.