Additive manufacturing (AM) can enable complex and novel designs that are otherwise infeasible with traditional metal manufacturing techniques. In low-volume production scenarios, particularly for specialized applications which can benefit from customized designs, traditional metal manufacturing techniques may be limited by costs associated with tooling. The ability to produce novel designs is particularly interesting in heat exchanger (HX) design where performance is often largely based on the achievable geometry. However, consequences of the AM process such as surface roughness, deviation from specified dimensions, and defects such as cracks and voids could also affect HX performance. These effects may vary between identically designed AM parts based on AM machine settings. The goal of this work is to gain a better understanding of the performance variations across several different implementations of the same heat exchanger design. More specifically, the objective of this work is to experimentally compare the thermal and hydraulic performances of a traditionally manufactured, stamped-aluminum aircraft oil cooler and three geometrically equivalent, additively manufactured counterparts. Compared to the traditionally manufactured heat exchanger, the AM HXs exhibited significantly higher air-side pressure loss and higher heat transfer despite having nominally similar geometries. Between AM HXs, there were slight differences in surface roughness characteristics based on optimal profilometry measurements. In addition, the thickness of the air-side fins varied as much as 15 percent between the AM HXs. The net effect, without the contribution of each cause clear, was higher air-side pressure loss and slightly higher heat transfer for the AM HX with thicker fins. This study indicates that functional heat exchangers built using AM vary in performance even when the same digital model is used to print them, and that AM HXs as a group perform considerably differently than their traditional counterparts. Thus, there is a need to account for anticipated surface roughness, geometric deviations, and potential defects when designing HXs. Proper consideration could result in improved thermal performance for future heat exchangers.

Simulation of a single flexible fiber suspension solved using partitioned fluid structure interaction (FSI) strategy is presented in this paper. The study of fiber motion during injection modeling process in composite material manufacturing is the motivation of this research. Fluid field is solved by mixed finite element method (FEM). Stokes equation is used as governing equation due to low Reynolds number characteristics. Total Lagrangian (TL) incremental FEM is used for calculating flexible fiber translation, rotation and deformation. Bathe time integration method is used for solving fiber dynamics. The interaction between the fiber (solid) and fluid results from forces on the surface of fiber, which are extracted from fluid solver and are exerted on fiber, solved as the natural boundary condition. After solid solver running forward a certain time step, new positions and velocities of each node on fiber surface are obtained which can be used for updating fluid mesh domain and served as essential boundary condition of fluid field. The process continues until the motion and deformation of fiber are obtained. Example of rigid and flexible fiber motion in a simple shear flow and a Poiseuille flow are presented in this paper. The simulation of rigid fiber are very close to the result of Jeffery’s theory. Snake rotation can be observed when the flexible fiber was tested in Poiseuille flow.

Over the past two decades, induction heating technology has begun to replace conventional heating methods in manufacturing due to its ability to rapidly and uniformly heat conductive materials. This advancement has made induction heating very attractive to a wide range of industries, including applications in which thin sheet geometries are used (sheet thickness < 10 mm). According to preliminary testing, conventional coil geometries cannot efficiently heat thin sheet samples. Thus, the primary goal of this study is to investigate a suitable coil design for thin sheet materials and to evaluate the effects of varying coil design parameters. To this end, this project has developed a 3D Multiphysics model that includes a longitudinal induction coil and a thin sheet workpiece. Using the model, a series of parametric studies have been performed to identify the best induction coil geometry for heating of thin sheets along with suitable excitation parameters for the coil and workpiece. It was found that uniform heating is produced when the space between coils is tight. Additionally, insignificant variance in temperature uniformity was found when vertically displacing the workpiece within the coil. Parametric studies resulted in finding a cross-section geometry that reduced temperature deviation to within 1.1% across the workpiece width. The model can be used as a design tool for developing a (full-scale) prototype induction heating system.

Associated with manufacturing and assembly processes, inevitable geometric deviations have a decisive influence on the function and quality of products. Therefore, their consideration and management are important tasks in product development. Moreover, to meet the demand for short development times, the front-loading of design processes is indispensable. This requires early tolerance analyses evaluating the effect of deviations in a design stage, where the product’s geometry has not yet been finally defined. Since such an early tolerance consideration allows quick and economic design changes seeking for robust designs, it is advisable that the design engineer, who is entirely familiar with the design, should take this step. For this purpose, this paper presents an easy-to-use CAD-based tolerance analysis method for skeleton models. The relevant part deviations are represented by varying geometric dimensions with externally driven family tables. The approach comprises the strength of vector-based methods but does not require an expensive set-up of tolerance analysis models. Particularly, the novelty of this method lies in the CAD-internal sampling-based tolerance analysis of simple geometries without the use of expensive CAT software. This enables designers to evaluate the effect of tolerances already at the preliminary design stage. Using a case study, the presented approach is compared with the conventional vector-based tolerance analysis.

With the developments and applications of the advanced information technologies such as cloud computing, internet of thing, artificial intelligence and virtual reality, industry 4.0 and smart manufacturing era are coming. In this respect, one of the specific challenges is to achieve a connection of physical resources on the shop floor with virtual resources, for real-time response, real time process optimization, and simulation, which is merged by big data problem. In this respect, Digital Twins (DT) concept is introduced as a key technology, which includes physical resources, virtual resources, service system, and digital twin data. DT considers current condition of physical resource and prediction of future events to make a responsive decision. However, due to the complexity of building a digital equivalent in virtual space to its physical counterpart, very little applications have been developed with this purpose, especially in the industrial manufacturing area. Therefore, the types of data and technology required to build the DT for a manufacturing system are presented in this work, trying to develop a framework of DT based manufacturing system, which is supported by the virtual reality for virtualization of physical resources.

Recently, PDMS has been widely used because of its outstanding properties, such as its biocompatibility, moldability, and Mechanical Flexibility. However, the low mechanical strength hinders its ability for further applications. The Addition of graphene oxide (GO) into Polydimethylsiloxane (PDMS) matrices as a reinforcement is a reasonably simple way to improve its mechanical properties. Direct ink writing (DIW) is an ideal method for printing viscous materials which provides useful advantages for fabrication, such as higher design freedom, as well as having no requirement for a castable mold, compared to conventional PDMS processing methods. Herein, we demonstrate the DIW 3D printing of GO reinforced PDMS matrix composites. PDMS SE 1700 and Sylgard 184 were mixed in 4:1 and 7:3 ratios as matrix materials with controlled rheological properties. GO, synthesized by modified Hummer’s method, was loaded into PDMS at various weight ratios (0.5%, 1%, 2%, 3% and 4%) to fabricate GO/PDMS composites. The GO dispersed uniformly throughout the PDMS matrix with no visible aggregation during the mixing and printing processes. Tensile tests were performed using 3D printed dog-bone shape GO/PDMS bars to evaluate the enhancement of the GO reinforcement. The results showed that the Young’s modulus of PDMS increased by 58.7% with 1% GO reinforcement.

An important goal of the manufacturing process is to achieve high accuracy and reliability of products. For modern equipment manufacturing industries, such as high-speed trains (HST), the assembly performance is guaranteed by the product design and manufacturing technique. Since dimensional control is much related to manufacturing quality, assembly variation analysis methods play an increasingly crucial role in advanced manufacturing industry. Nevertheless, the relationship between welding distortions and tolerance design has not been considered in most existing assembly variation analysis models, which lack of quantitative analysis between precision and performance. In this study, a compliant variation analysis methodology considering both static structural deformation and welding distortion is developed and applied to predict assembly variation of the roof of HST. Firstly, welding simulation is carried out to predict welding shrinkage and angular distortion with different welding configurations. Then, welding distortion is equivalent to dimensional variation and considered in the compliant variation analysis model with offset tolerance technique. Finally, a compliant variation simulation is carried out to investigate the variation propagation influence of welding shrinkage and distortion on the final dimension of assembly. The presented methodology provides an efficient tool for variation analysis of HST, also offers a theoretical basis and experimental support for mechanical properties of compliant assembly.

Virtual reality (VR) is becoming increasingly popular in educational applications, but insufficient users’ feel of immersion often slows the further adoption of VR. Many solutions with a focus on the results rather than the details of the interactions between the objects in the real and virtual worlds have been developed. Therefore, the real procedures are distorted and the users lose their perception of in-person participation. In order to improve the users’ feel of immersion further and to simulate more realistic operations in VR, a procedure-oriented approach for the combination of real and virtual environments is proposed here. As its name implies, this approach emphasizes the details of the procedures, namely how to capture, track, operate and interoperate the real and virtual objects in a mixed environment. In order to illustrate this idea, a prototype of mixed real and virtual assembly, in con-junction with object recognition and rigid-object tracking functions based on robotic vision techniques, is presented as an example. This prototype is designed based on a game-based virtual laoratory system, and the specific implementation is a planetary gear train experiment. In this experiment, all models of the parts with the information required for the assembly are created, labeled and added to the database of the virtual laboratory system. The physical parts are marked in order to facilitate object recognition and object tracking. During the experiment, the main assembly with one missing planetary gear is accomplished in a purely virtual environment. In the real world, the missing planetary gear is tracked by a Kinect while the user is manipulating this gear. Then, the system recognizes this gear based on the markers and couples the corresponding virtual model of that gear with the avatar’s hand in the virtual environment. Afterward, the cam-era tracks the real part, and the user can adjust its pose and location to finish the final assembly. The main benefit of this implementation is that the user can take advantage of some simple real parts in conjunction with virtual models of sophisticated parts in order to get realistic experience with the assembly process.

Cyber Manufacturing system (CMS) is the future of manufacturing system integration, which can completely change the manufacturing industry in all areas to benefit everyone from the companies to the consumers. This research paper describes how this form of manufacturing can be achieved through the cooperation of several areas of digital manufacturing. The included Manufacturing Automation Framework displays how the different systems can work together to achieve successful cyber manufacturing. The framework provides the basic structure of the system needed to easily transfer the technology and ideas to various industries.

The objective of the NSF RET (Research Experiences for Teachers) site program hosted by the University of Central Florida is to provide K-12 teachers with a hands-on engineering design experience covering all aspects of the Internet of Things, from the manufacturing of a sensor, to the hardware and software that allows it to connect to the Internet. This program gives teachers learning opportunities to explore the practical use of science for engineering applications, and provide a context in which students in their classroom can test their own scientific knowledge as they recognize the interplay among science, engineering and technology. The uniqueness of this site program lies in the engagement of teachers in various facets of scientific, engineering, and educational methods based on Train-the-Trainer model with rotation in multiple research labs. In order to support the STEM educational services for teachers and students in middle and high schools, our site program aims at creating competent teacher trainers who ensure quality pre-service and in-service teacher education, by providing multidisciplinary experiences that are relevant to the current technical development. Teachers in the adjacent public school districts are primary participants in this site program. Significant efforts have been made to recruit teachers serving underrepresented student populations, and female and minority teachers who can reach out to them. In our RET site program, the participants rotated to four different laboratories with a 1.5–3 week residency in each, where they learned about the practice of engineering in various disciplines at the research laboratories on the university campus under the guidance of faculty and graduate mentors. The teachers presented their learning outcomes in the final week and were invited back to share their educational implementation experiences in their classes. This site program provided teachers with interdisciplinary engineering design experiences relevant to innovative technical development, and helped them develop teacher-driven teaching modules that can be deployed in the classroom.

Robotic co-workers are an emerging generation of physical robots promises to transform manufacturing with its ability to communicate and collaborate, both robot-to-robot and robot-to-human, opening the way to greater innovation and productivity. We designed a welding robotic co-worker which observes industrial part, searches welding seams, plans welding trajectory, and simulates welding result automatically. It largely benefits small and medium-sized manufacturing enterprises (SMEs) by allowing manufacturers handle low-volume orders without re-programming. As a co-worker, the robot communicates with its operator though brain computer interface (BCI) as well as guarantees the operator’s safety. We demonstrated the performance of this robot using a human subject study in welding simulation environment.

Tube forming is one of the most common manufacturing processes to shape the tubes. Within tube forming operations the general practice is to expand and reduce the tube end cross-section and bend the tube by means of a solid mandrel. Mostly the mandrel is rigid bodies. To reduce the friction between the tube and the tool, tube hydroforming process was evolved in which the fluid was highly pressurized to expand the tube shape to the desired shape. By reducing the friction more uniform thickness could be achieved and thus increase in formability. One of the process within tube end forming process is flaring which is the focus of this paper. In tube flaring process the conical shape rigid tool flares the end of the tube. While flaring the tube, the tube buckles if proper consideration would not have been taken. In this paper, various influencing parameters such as outer diameter to tube thickness ratio, length or the tube, the strength coefficient of the tube and conical angle of the tool were analyzed. It was noted that the most important factor affect the buckling of the tube is its strength coefficient. Considering this parameter the buckling was carried out in a set die and a tube shape was formed. The advantages of this process over similar processes were discussed.

Additive manufacturing (AM) technology is becoming more popular for the fabrication of 3D metal products as it offers rapid prototyping and large design freedom. However, part quality and fatigue performance of components fabricated by current AM technology are not comparable to that produced by traditional methods. Post-build processing techniques, such as heat treatment (HT) and Hot Iso-static Pressing (HIP), have been developed to improve microstructure and remove internal flaws that are detrimental to fatigue resistance. In order to simulate the HT and HIP process and optimize the post-build process, an integrated computational materials engineering (ICME) approach is utilized to link the process parameters with material’s structures, properties, and fatigue performance. The purpose of this study is two-fold. First, we simulate the HT/HIP process including the physics of heat transfer, and porosity evolution. Second, a state-of-the-art hybrid optimization approach, combining response surface method and genetic algorithm is utilized to optimize the post-build process parameters in order to minimize porosities.

Internet of things or IoT represents an emerging concept where the objects and humans are identifiable, connected and can communicate over the internet or the wireless world. With IoT, everything can communicate anytime and at anyplace. IoT has many applications and one of the most important applications is the manufacturing. The IoT in industry sector, sometimes referred to as IIoT, is considered to be a very important factor in the introduction of the fourth industrial revolution. Major manufacturing powers around the world are already trying to adopt IoT in their production systems and lead the way in this new era of advanced manufacturing. A huge number of IoT devices are already being used and connected and it is expected that the number of these applications and devices will increase dramatically in the next few years. In this work, an overview of IoT in manufacturing will be presented. This includes a discussion of some of the advantages and benefits of adopting IoT in manufacturing in addition to the issues and challenges that accompany this IoT application. The discussion will also include the concept of smart manufacturing, how production processes and other related activities can be connected in real time and how this can be achieved by adopting IoT in manufacturing. Furthermore, the enabling technologies needed to realize IoT (whether it is to be applied in a new plant or in already existing machines that don’t have IoT capabilities) are shown along with the different layers or phases needed for this IoT adoption. Finally, some real life examples of factories that adopted IoT are shown.

The lumbar puncture (LP) procedure is a diagnostic procedure that is performed to identify the root cause behind symptoms which can often be caused by various diseases or infections. Currently, medical students will either perform LPs directly on live patients with only theoretical knowledge of the procedure, or they will first be trained using unrealistic models that give a poor representation of the procedure. Traumatic taps (poorly performed LPs) were found to occur in approximately 15% of adult patients, and 35% in children. To reduce these complications, it is necessary that medical students receive the best training possible, which can be made possible through utilizing advanced design and manufacturing technologies. The training mannequin should be flexible, have realistic tissue force resistance, and be reconfigurable for different body types, and age groups. A parametric CAD model is developed that can be modified to represent key structural dimensions from infant to adults, force testing is conducted on a cadaver to determine the puncture forces, and more realistic ‘tissue’ materials are derived via experimentation as the existing training models have noticeably different resistance characteristics. The individual elements for a new training mannequin solution have been determined. Additive manufacturing processes can readily fabricate the vertebrae and pelvis elements, as well as the specialty molds. A final model assembly, and field testing, needs to be performed.

The growing demand of miniaturized products is tremendously influencing the progress of micro-forming technologies. The implementations of micro technologies in the field of microelectronics, sensors, and medical equipment necessitate versatile micro-forming processes. These processes facilitate the bulk production of micro parts with higher precision, minimum material waste, and better surface finish. However, micro-forming technologies are still expensive due to the limitations of traditional materials and stringent size requirements. Finite element simulations are being widely used to analyze the manufacturing process parameters before going into production. In this research, a backward micro-extrusion process is simulated for annealed copper by using commercial Finite element simulation software. The effects of different punch diameters, friction coefficients, punch velocities on the load-displacement curves and the resulting strain distributions are investigated. To overcome limitations of the post-yield hardening data from the uniaxial compression test, the Ramberg-Osgood model is proposed to predict the responses at the higher plastic strain.

An approach for simulating the assembly process where compliant airframe parts are being joined by riveting is presented. The foundation of this approach is the mathematical model based on the reduction of the corresponding contact problem to a Quadratic Programming (QP) problem. The use of efficient QP algorithms enables mass contact problem solving on refined grids, which is needed for variation analysis and simulation as well as for the consequent assembly process optimization. To perform variation simulation, the initial gap between the parts is assumed to be stochastic and a cloud of such gaps is generated based on statistical analysis of the available measurements. The developed approach is illustrated with two examples, simulation of A350-900 wing-to-fuselage joining and optimization of A320 wing box assembly. New contact quality measures are discussed.

A substantial increase in demand on the sheet metal part usage in aerospace and automotive industries is due to the increase in the sale of these products to ease the transportation. However, due to increase in the fuel prices and further environmental regulation had left no choice but to manufacture more fuel efficient and inexpensive vehicles. These heavy demands force researchers to think outside the box. There are many advanced manufacturing processes to produce optimized part are single and double point incremental forming, Reuleaux forming, hydroforming, explosive forming, electrically assisted manufacturing. In this project, a numerical study on rotational tube flaring process will be studied. Tube flaring is one of the most commonly used processes under tube forming. In this process, a conical tool contacts and forces the end of the tube while another end of the tube is fixed. This is called conventional flaring process. In contrast to this process, a tool rotational technique was utilized for this work. The rotation and the feed of the tool will be analyzed to have the best formability of the tool. The strain path and failure will be analyzed. The strain and thinning pattern will be discussed.

This paper addresses the curriculum change in the mechanical engineering (ME) undergraduate program at the Universidad Pontificia Bolivariana (UPB), located in Medellin, Colombia. The curriculum model of the UPB is based on develop of Human Capabilities and Professional Competences, through of learning and the achievement of outcome-related course learning objectives during the education process. The faculty of the ME department developed the Human Capabilities and Outcomes Map. This map shows the connection between general human capabilities that are strengthen through the ME program, the competences that are to be achieved, and the courses where the outcomes are developed in the curriculum. The courses organized in four technical areas: Design and Control, Materials and Manufacturing Processes, Energy and Thermofluids, and Management. The curricular design includes too the incorporation of four courses with integrator character. These courses are called Modules of Applied Engineering. In them, the student develops projects of engineering of low complexity; These projects involve the integration of topical courses in technical areas and the intentional development of human capacities and transversal competences. The faculty will assess the performance within a two-year period in order to quantify the impact of the curricular proposed.

Variation simulation for assembled products is one important activity during product development. Variation simulation enables the designer to understand not only the features of the nominal product but also how uncertainty will affect production, functions and the aesthetic properties of the final product. For parts that are able to deform during assembly, compliant variation simulation is needed for accurate prediction. For this the Finite Element Method (FEM) is used. Despite many effective efforts to decrease simulation times for compliant variation simulation, simulation time is still considered an obstacle for full scale industrial use. In this paper, a new formulation for compliant variation simulation of assemblies that are joined in sequential spot-welding will be presented. In this formulation the deformation in the intermediate springback steps during the simulation of a spot-weld sequence do not have to be calculated. This is one of the most time consuming steps in sequential spot-welding simulation. Furthermore, avoiding the intermediate springback calculation will reduce the size of memory of the computer models since the number of sensitivity matrices is reduced. The formulation is implemented using the latest developments in compliant variation simulation, that is the Method of Influence Coefficients (MIC) where the Sherman-Morrison-Woodbury-formula is used to update the resulting sensitivity matrices and the contact- and weld forces are solved using a Quadratic Programme (QP). Industrial cases are used to demonstrate the reduced simulation time. It is believed that the reduction in simulation times will have future implications on sequence optimization for spot-welded assemblies.