Actuators are the key to sophisticated machines that can perform complex tasks previously done by humans.
Abstract 3D Printing is a revolutionizing technology extensively used in automotive and aerospace industries. It is an additive layer manufacturing process by which a scale model is quickly fabricated from CAD data in just a matter of hours. In Automotive trims, 3D Printing technology is a boon. It is used: To simulate the ‘tooled up/production part’ in terms of assembly, defined function, limited CMF and fit & finish. To evaluate and capture early feedback from top management with respect to aesthetic, design, etc. For early prediction and plan of action towards improvement for craftsmanship. To reduce design iterations, interface concerns, product lifecycle time and cost. In this paper, we will discuss on the technical aspects of how the trims 3D printed models have been effectively put to use. We have covered case studies under door trims, floor console, tail gate trim, glove box latch, molded spare wheel cover, Instrumental panel duct and bumper mask-painting template.
NASA has embarked on an ambitious program to integrate additive manufacturing techniques and to develop processes for the microgravity environment. The most recent example of this program is the successful launch and deployment of the first 3D printer on the International Space Station. In this one-year effort, students were required to meet a series of milestones to design, manufacture, and test their ideas in close cooperation with members of the NASA Exploration Augmentation Module (EAM) concept team.The participants in this project were tasked with thinking of new solutions using AM that would simultaneously be recyclable with minimal loss in mechanical properties but also have the capacity for high mechanical properties. Working in interdisciplinary teams, the participant teams investigated the use of recycled materials, characterization, testing, modeling, and tool development.
Abstract Additive manufacturing (AM) of metals is finding numerous applications in automotive industry. In 21st century, aluminum is second to steel in automotive sector, because of its high strength to weight ratio. Hence developing AM for aluminum alloys become necessary to make sure industry gains maximum benefit from AM. This study specifically deals with the manufacturing of Al 7050 alloy, which is quite hardest alloy to manufacture using AM. The ultimate goal is to optimize the laser deposition parameters to deposit defect free Al 7050 alloy on rolled aluminum alloy substrate. Parameter optimization (laser power, powder flow rate, and scanning speed) gets difficult with the presence of various low melting and boiling point alloying elements such as Zn, Mg etc. Numerous other challenges faced while depositing Al 7050 alloy, are also briefly discussed in this article.
Investigating Process Parameters and Microhardness Predictive Modeling Approaches for Single Bead 420 Stainless Steel Laser Cladding
Abstract Laser cladding is a novel process of surface coating, and researchers in both academia and industry are developing additive manufacturing solutions for large, metallic components. There are many interlinked process parameters associated with laser cladding, which may have an impact on the resultant microhardness profile throughout the bead zone. A set of single bead laser cladding experiments were done using a 4 kW fiber laser coupled with a 6-axis robotic arm for 420 martensitic stainless steel powder. A design of experiments approach was taken to explore a wide range of process parameter settings. The goal of this research is to determine whether robust predictive models for hardness can be developed, and if there are predictive trends that can be employed to optimize the process settings for a given set of process parameters and microhardness requirements.
Abstract The recent contribution rise in 3D printing is rapidly changing the whole industry. In aeronautics, it has 2 major domains of growth: Aircraft parts Tooling and portable tools Aircraft parts in metallic 3D printing have been highly publicized in the media, although they represent only a tiny share of the aircraft cell in the short term. On the other hand, metallic (and non-metallic) 3D printing in tooling and tools can bring immediate advantages compared to traditional methods. The advantages: Design made directly for the final function Optimized for strength vs weight Weight reduction Reduction in number of parts Short cycle time from design to use Low cost for customization The drawbacks Limited in size We have already applied this new manufacturing technique to obtain real breakthroughs in portable tools.
Abstract Gaps in composite structures are a risky factor in aeronautical assemblies. For mechanically joined composite components, the geometrical conformance of the part can be problematic due to undesired or unknown re-distribution of loads within a composite component, with these unknowns being potentially destructive. To prevent unnecessary preloading of a metallic structure, and the possibility of cracking and delamination in a composite structure, it is important to measure all gaps and then shim any gaps greater than 127 microns. A strategy to overcome the high relative tolerances for assemblies lies in the automated manufacturing of shims for the gaps previously predicted through the evaluation of their volumes via a simulation tool. This paper deals with the development of a special end-effector prototype to enable the shimming of gaps in composites structures using a pre-processed geometry.
Abstract Induction machines (IM) are considered work horse for industrial applications due to their rugged, reliable and inexpensive nature; however, their low power density restricts their use in volume and weight limited environments such as an aerospace, traction and propulsion applications. Given recent advancements in additive manufacturing technologies, this paper presents opportunity to improve power density of induction machines by taking advantage of higher slot fill factor (SFF) (defined as ratio of bare copper area to slot area) is explored. Increase in SFF is achieved by deposition of copper in much more compact way than conventional manufacturing methods of winding in electrical machines. Thus a design tradeoff study for an induction motor with improved SFF is essential to identify and highlight the potentials of IM for high power density applications and is elaborated in this paper.
Abstract It is desired to reduce stator end winding length and mass to reduce associated resistive losses, increase efficiency and power density of an induction motor. With recent advancements in additive manufacturing technology, it is possible to deposit copper conductive paths and insulation layers in a selective controlled manner. This enables more compact end winding designs. The objective of this paper is to present a topology optimization based approach for design of stator end winding to minimize its overall length, volume and mass. Design approach and parametric study results for a representative stator design are presented in this paper. By reducing length of end winding, efficiency and power density of the induction motor can be increased enabling benefit realization for weight critical aerospace applications, incorporation in electric vehicle market and potentially reducing rare-earth dependency.
Abstract Additive manufacturing has experienced rapid growth over a span of 25 years. Additive manufacturing involves the development of a three-dimensional (3D) object by stacking layer upon layer. Conventional machining techniques involve the removal of material. However, this technique differentiates itself from other techniques by means of addition of the material. The integration of CAD with additive manufacturing has offered the ability to create complex structures. Despite its clear benefits, additive manufacturing suffers from a high initial investment. An average cost of an entry level commercial 3D printer is 600$. A low-cost 3D printer has been designed and built for experimental investigation within a budget of 300$. The paramount process of 3D printing involves a combination of interpreting data from CAD files and controlling the motors using this data. The various design considerations while developing the 3D printer have been discussed.
Abstract Due to its unique physical properties (high thermal and electric conductivity) copper is one of the most interesting materials in point of view of additive manufacturing in particular of Selective Laser Melting (SLM). But because of the low laser radiation absorption, low melting point and high thermal conductivity it is difficult to fabricate of copper components without pores. Results of many research have been shown that for successful Selective Laser Melting of copper powder is needed high laser power (more than 300 W) and high laser scanning speed (more than 600 mm/s). However now most SLM machines are equipped with laser plants with output power up to 200 W.In this research, SLM machine with 200 W maximum power CO2 laser has been used. For determination of the influence of SLM process parameters on quality of copper parts cubic specimens have been fabricated. The point distance, exposure time and base plate preheating temperature have been changing.
Big Area Additive Manufacturing and Hardware-in-the-Loop for Rapid Vehicle Powertrain Prototyping: A Case Study on the Development of a 3-D-Printed Shelby Cobra
Abstract Rapid vehicle powertrain development has become a technological breakthrough for the design and implementation of vehicles that meet and exceed the fuel efficiency, cost, and performance targets expected by today’s consumer. Recently, advances in large scale additive manufacturing have provided the means to bridge hardware-in-the-loop with preproduction mule chassis testing. This paper details a case study from Oak Ridge National Laboratory bridging the powertrain-in-the-loop development process with vehicle systems implementation using big area additive manufacturing (BAAM). For this case study, the use of a component-in-the-loop laboratory with math-based models is detailed for the design of a battery electric powertrain to be implemented in a printed prototype mule. The ability for BAAM to accelerate the mule development process via the concept of computer-aided design to part is explored.
Barriers to Entry in Automotive Production and Opportunities with Emerging Additive Manufacturing Techniques
Abstract Conventional car manufacturing is extremely capital and energy-intensive. Due to these limitations, major auto manufacturers produce very similar, if not virtually identical, vehicles at very large volumes. This limits potential customization for different users and acts as a barrier to entry for new companies or production techniques. Better understanding of the barriers for low volume production and possible solutions with innovative production techniques is crucial for making low volume vehicles viable and accelerating the adoption of new production techniques and lightweight materials into the competitive marketplace. Additive manufacturing can enable innovative design with minimal capital investment in tooling and hence should be ideal for low and perhaps high volume parts. For this reason, it was desired to evaluate potential opportunities in manufacturing automotive parts with additive techniques.
Abstract Biologically inspired designs have become evident and proved to be innovative and efficacious throughout the history. This paper introduces a bio-inspired design of protective structures that is lightweight and provides outstanding crashworthiness indicators. In the proposed approach, the protective function of the vehicle structure is matched to the protective capabilities of natural structures such as the fruit peel (e.g., pomelo), abdominal armors (e.g., mantis shrimp), bones (e.g., ribcage and woodpecker skull), as well as other natural protective structures with analogous protective functions include skin and cartilage as well as hooves, antlers, and horns, which are tough, resilient, lightweight, and functionally adapted to withstand repetitive high-energy impact loads. This paper illustrates a methodology to integrate designs inspired by nature, Topology optimization, and conventional modeling tools.
Abstract Cycloid drives are widely used in the in-wheel motor for electric vehicles due to the advantages of large ratio, compact size and light weight. To improve the transmission efficiency and the load capability and reduce the manufacturing cost, a novel cycloid drive with non-pin design for the application in the in-wheel motor is proposed. Firstly, the generation of the gear pair is presented based on the gearing of theory. Secondly, the meshing characteristics, such as the contact zones, curvature difference, contact ratio and sliding coefficients are derived for performance evaluation. Then, the loaded tooth contact analysis (LTCA) is performed by establishing a mathematical model based on the Hertz contact theory to calculate the contact stress and deformation.
Abstract Pressure and temperature levels within a modern internal combustion engine cylinder have been pushing to the limits of traditional materials and design. These operative conditions are due to the stringent emission and fuel economy standards that are forcing automotive engineers to develop engines with much higher power densities. Thus, downsized, turbocharged engines are an important technology to meet the future demands on transport efficiency. It is well known that within downsized turbocharged gasoline engines, thermal management becomes a vital issue for durability and combustion stability. In order to contribute to the understanding of engine thermal management, a conjugate heat transfer analysis of a downsized gasoline piston engine has been performed. The intent was to study the design possibilities afforded by the use of the Selective Laser Melting (SLM) additive manufacturing process.
Abstract Rapid advances in cloud-based computing, robotics and smart sensors, multi-modal modeling and simulation, and advanced production are transforming modern manufacturing. The shift toward smaller runs on custom-designed products favors agile and adaptable workplaces that can compete in the global economy. This paper and presentation will describe the advances in Digital Manufacturing that provides the backbone to tighten integration and interoperability of design methods interlinked with advanced manufacturing technologies and agile business practices. The digital tapestry that seamlessly connects computer design tools, modeling and simulation, intelligent machines and sensors, additive manufacturing, manufacturing methods, and post-delivery services to shorten the time and cost between idea generation and first successful product-in-hand will be illustrated.
Abstract The performance of a 4cc two-stroke single cylinder glow plug engine was assessed at wide open throttle for speeds ranging from 2000 to 7000RPM. The engine performance was mapped for the stock aluminum head and one composed of titanium, which was printed using additive manufacturing. The engine was mounted to a motoring dynamometer and the maximum torque was determined by adjusting the fuel flow. Maximum torque occurred around 3000 to 3500RPM and tended to be higher when using the aluminum head. At slower speeds, the titanium head produced slightly higher torque. For each test condition, maximum torque occurred at leaner conditions for the titanium head compared to the stock aluminum one. Higher efficiencies were observed with the aluminum head for speeds greater than 3000RPM, but the titanium heads provided better efficiency at the lower speed points.
A turbulent CFD simulation based on the Large Eddy Simulation approach (LES) is under development at Autodesk. The code is being designed to provide designers with rapid estimates of drag coefficient early in the product development phase. The efficacy of this approach depends on the solver's ability to predict drag with reasonable accuracy. To this end a series of wind tunnel experiments were performed to measure drag on a model automotive body and validate the computational results. An automobile CAD model was transformed into a physical object by 3D printing at one fifth scale. Wind tunnel testing included drag coefficient variation with wind speed, yaw angle, wake maps of velocity and turbulence intensity, and high speed photography of smoke and helium bubble flow over the automobile surface and rear. A CFD simulation incorporating an integrated rapid voxel mesher was used to simulate each experiment.
This paper examines the use of additive manufacturing and the composite SLS material Windform XT to build a 2U CubeSat with an integrated Micro-Electro-Mechanical System (MEMS) propulsion for space flight. The flight of this satellite is intended to examine and test the use of additive manufacturing utilizing Windform XT to produced CubeSat's, as well as certifying a warm gas propulsion subsystems with a magnetic stabilization for CubeSat orbital altitude adjustment. The RAMPART project uses additive manufacturing techniques to build the satellite structures, propellant tanks, printed circuit board cages, solar panel frames, antenna deployment mechanisms, etc. at a fraction of the time of current methods. Materials developed by CRP Technology for use in Formula 1 and NASCAR, with improved mechanical and thermal properties are being adapted for use in space. This paper describes the use of these techniques to design and build a 2U CubeSat.
Honeywell has developed a new approach to Solid Free-form Fabrication called Ion Fusion Formation (IFF), a Direct Metal Deposition (DMD) process. This is a near-net-shape hardware manufacturing process that uses a very hot ionized gas to deposit metal in small discreet amounts and ultimately build a complete part. Components can be used as-deposited or post-deposition processed to gain some improvement in properties and then final machined. The process has low initial capital, maintenance and operating cost and is user friendly. Other forms of SFF use expensive lasers or electron beam for their heat source. IFF uses inexpensive electrical energy to generate power for fusion.
A small-scale flow rig has been constructed to investigate the swirl behavior of various intake manifold configurations. This effort is to support the development of a 10cc-size, single-valve reverse uniflow 2S engine. In this reverse uniflow geometry the incoming charge enters through a single valve in the engine head, and the burned gases are exhausted through symmetrically-arranged ports in the cylinder wall near bottom dead center. Port-directioning of the fresh charge, used in conventional (bottom-up) uniflow arrangements, is not available with this geometry, so another means to control the cylinder sweeping is sought. The flow rig has been constructed on a 2:1 scale, and three preliminary intake manifold configurations have been prototyped using a 3D printing machine. A straight manifold, a ramped tangential manifold and a basic helical design were manufactured.
The traditional use of simulation software in aerospace manufacturing applications has been as a pre-production tool for the validation of tool paths and the generation of robot programs. Once the process has been proven via simulation, the data is then transferred to the machine or robot and the production process executed. This is a linear approach in which the virtual and real systems are operated independently and in a serial manner. The current capabilities of offline programming (OLP) and simulation systems when combined with appropriate hardware in a flexible manufacturing environment now allow them to be used right at the heart of a manufacturing process, as an integral part of the manufacturing route. In a flexible manufacturing cell such as that developed at the University of Nottingham for the automated assembly and riveting of large aerostructures, a key driver is the need to reduce or eliminate complex and costly jigs and fixtures for part positioning.
SLAM, A Fast High Volume Additive Manufacturing Concept by Impact Welding; Application to Ti6Al4V Alloy
Against the manufacturing requirement for both lower lead time and reduced machining time for titanium components, a new concept was conceived assembling sheet material and other stock into semi finished parts by (explosive) impact welding. It is believed that this concept (which we named SLAM) could be especially beneficial for titanium alloy and nickel alloy. The present investigation centered on the feasibility of this technology for the widely used Ti6Al4V alloy. Impact process parameters were established and mechanical properties were investigated. In general, static properties were good. Fatigue strength reduced however, although much less so for notched specimens compared to un-notched material. Fatigue crack initiation could be linked to complex features within the (wavy) weld interface associated with the ‘first generation’ impact welding parameters. Next steps are foreseen to improve the fatigue performance.
Laser additive manufacturing technology allows the fabrication of complex metal components that would not be possible to make using conventional methods. Uprights play an important role in the performance of an open wheel racecar suspension system by transferring forces from the tire to the vehicle frame and shock assembly. The upright design for the 2004 South Dakota School of Mines and Technology's (SDSM&T) Formula SAE vehicle that met all the proposed functional requirements was found using a comprehensive design process. It consisted of a thin-walled hollow structure with minimal supporting ribs that could not be manufactured by a single available conventional manufacturing method and thus was an ideal candidate for laser additive manufacturing. To fabricate this “shell” design, the SDSM&T's laser-powder-deposition (LPD) machine was employed.
One aim of all companies worldwide is the fast building of new tools or parts to start a new series of production. However, in reaching the goal of fast production, many changes may arise between the idea and the final product due to new ideas, unforeseen difficulties, changes in design, etc. These changes often cost valuable time. The goal remains to find a technology which offers fast building of parts or tools with high quality results. Which technologies can be used and offer a good solution to this problem? In my presentation, I will show how it is possible to build tools or parts within the molding technology using the Rapid-Prototyping method, “3-D-Printing with wax.”