Data Acquisition During the Entire Product Life Cycle as a Basis for the Maintenance, Dismantling and Product Recycling Processes

The planning and control of recycling and disassembly processes depends to a great extent on information about the product and its usage. A substantial amount of information about products is provided on delivery, but a continuous and systematic recording of information during a product life is normally not carried out. Repairs, disassembly and product recycling are however dependent on decentralised and information-intensive processes and can only be facilitated through the recording of life-cycle information. All information which is generated during the product life is first integrated into a newly created information model for life-cycle documentation. The paper presents a new integrated approach that guarantees consistent data storage and data structuring during the entire product life. An innovative information system is introduced which can provide any required information to all product user groups at any point in the product life. One module of this model is the electronic life-cycle memory for data storage on the product itself of the life-cycle documentation. It is done using Radio Frequency Identification Technology (RFID) for the first time in this field. Subsequently, the integration of the life-cycle memory into the entire information system is described. The paper closes with a practical case from industry.

The Role and Limitations of Modeling and Simulation in Systems Design

To design today’s complex, multi-disciplinary systems, designers need a design method that allows them to systematically decompose a complex design problem into simpler sub-problems. Systems engineering provides such a framework. In an iterative, hierarchical fashion systems are decomposed into subsystems and requirements are allocated to these subsystems based on estimates of their attributes. In this paper, we investigate the role and limitations of modeling and simulation in this process of system decomposition and requirements flowdown. We first identify different levels of complexity in the estimation of system attributes, ranging from simple aggregation to complex emergent behavior. We also identify the main obstacles to the systems engineering decomposition approach: identifying coupling at the appropriate level of abstraction and characterizing and processing uncertainty. The main contributions of this paper are to identify these short-comings, present the role of modeling and simulation in overcoming these shortcomings, and discuss research directions for addressing these issues and expanding the role of modeling and simulation in the future.

Web-Based Collaborative Concurrent Engineering for Product Design and Manufacturing

We present a developed Web-based product design and manufacturing system that supports collaborative Concurrent Engineering. It models distributed systems and databases using Web technologies, so that these distributed system and databases can be accessed anywhere in the world. In such system, product developers can exchange and share product data, communicate with other team members, modify geometry data on particular aspects of the design and maintain operations consistency in all the distributed cooperative sites on a wide variety of platforms. The new system is a Client/Server architecture. The server manages the sharing of the common model, as well as the coordination among multiple users, in which different users can modify different parts of the shared model. In addition, the server supports many client through the Internet, and it also allows peer to peer negotiation, sharing different databases located in different machines, establishing relations between them at run time. A group of users can work together in a common single write mode, which continuously synchronized with the master copy on the central server. The proposal model is producing a new manner and has many algorithms for viewing, editing, synchronizing, and collaboration coordination. It utilizes Java 3D to view 3D CAD files in interactive manner. It introduces an intelligent user interface for editing and modification. STEP, which is international standard introduced by the International Standards Organization (ISO), is used to exchange engineering information. Java Server Page (JSP) is used for Collaboration coordination and semantic-based coordination.

Identifying and Processing Undesired Functions During Conceptual Design

This paper addresses the problem of product fault anticipation and prevention during conceptual design of mechanical engineering products by introducing the concept of undesired functions as potential fault causes. The undesired functions considered in this paper are induced during solution principle synthesis and affect a product either by reducing the input of its intended functions or by producing undesired outputs, and can be processed either by determining and optimizing their distribution function, or by finding inverse, consecutive or compensation functions to them. The formal definition of the generic process of processing undesired functions bases on its subdivision into elementary steps, each step being described by its states and the according state transition. Object patterns and process patterns are adopted for the representation of the static and dynamic design knowledge respectively. The concept is verified with a product example from mechanical engineering.

Undergraduate Finite Element Instruction Using Commercial Finite Element Software Tutorials and the Kolb Learning Cycle

As background, the Kolb learning cycle describes an entire cycle around which a learning experience progresses [1]. The goal, therefore, is to structure learning activities that will proceed completely around this cycle, providing the maximum opportunity for full student comprehension of the course material. This model has been used previously to evaluate and enhance teaching in engineering [2, 3, and 4]. Most college education is geared toward abstract conceptualiztion, but complete learning is enhanced by the use of all four learning stages Abstract Hypothesis and Conceptualization, Active Experimentation, Concrete Experience and Reflective Observation. Some parts of this paper were presented at an earlier conference [13]. The Finite Element (FE) method is a numerical procedure that is widely used to analyze engineering problems accurately and quickly in many corporations. It has become an essential and powerful analytical tool in designing products with ever-shorter development cycles [5, 6, and 7]. The use of commercial finite element software tutorials along with the Kolb model of learning has been used for the past three years to instruct undergraduate students in an introductory FE course. This paper provides outlines of the use of the commercial software tutorials using two Kolb learning cycles, a global learning cycle for the course and a micro learning cycle for the FE tutorials. The commercial FE software tutorials provide an excellent method to reinforce student’s retention of this complex numerical procedure. The software tutorials provide hands-on learning experiences that students need to reinforce the theoretical concepts covered in the lectures. The students are provided “Abstract Hypothesis/Conceptual Theory” that begins with the background of the FE method, fundamental mathematics of FE, move through the concept of “stiffness-analysis,” one-dimensional direct stiffness analysis of various structures, the topology of the various finite elements, error analysis of FE results, and concludes with engineering analysis of a typical engineering problem. These activities are interlaced with the hands-on MSC.Nastran1 software tutorials that begin stating the proposed problem in a manner that is “real-world” in nature then the student is supplied with background theory for the analysis they will attempt. The tutorials provide specific instructions on how to build the FE model of the problem using this commercial FEM code. The tutorial includes a step-by-step outline of the problem modeling with text and illustrations. The student then performs the analysis. Instead of doing this in a blind manner, the tutorial provides a connection to the abstract theory of FE and asks the student to perturb certain parameters in the model to predict the results apriori. This causes the students to make connections between the modeling techniques and the IMECE2004-60756 Undergraduate Finite Element Instruction using Commercial Finite Element Software Tutorials and the Kolb Learning Cycle underlying physics. This focuses in on the “Active Experimentation” part of Kolb’s cycle. After the student performs the analysis, they are asked to attempt to explain the differences between the FEM modeling and theoretical results. This requires students to engage in the “Reflective Observation” portion of Kolb’s cycle. In designing the learning experiences to completely transverse the Kolb cycle, students are fully engaged to understand the fundamentals of FE modeling and maximize the learning experience the tutorials provide. Near the conclusion of this course students are asked to develop prototype models of designs for engineering problems using FE and then asked to conduct experiments to verify their FE analysis. The Kolb model describes an entire cycle around which learning experiences progress Abstract Hypothesis and Conceptualization, Active Experimentation, Concrete Experience and Reflective Observation, and is shown below in Figure 1.

The Measure of the Machine: How Exposure to Current Technology Can Upgrade a Student’s Education

Over the past decade there has been a distinct trend toward implementing computer technology in education. The advent of affordable, student accessible computing power has allowed engineering curricula to follow the trends of computer technology in the engineering workplace. The developments in hardware and software, combined with the explosive entrance of the Internet, have allowed design projects to evolve into elaborate and imaginative endeavors. The enhanced speed at which projects can now be completed allows students the opportunity to undertake tasks of greater magnitude, while the advanced tools now available permit students to solve more sophisticated and lifelike problems. The examination of a senior-level design course, in which students must design and build a maze-solving robot, serves to highlight the educational benefits that stand to be gained through the judicious application of technology. The evolutionary history of this design course demonstrates the remarkable progress that computer technology has allowed in educational settings.

Geometric Dimension and Tolerance Modeling and Validation System Based on Object Oriented Paradigm for 3D Solid Model

This paper introduces an approach for modeling and representation of geometric tolerances on any 3D solid model using the Objected Oriented Programming (OOP) paradigm. The modeling scheme is supported by a comprehensive validation engine, which certifies the tolerance type against the 3D geometry context both syntactically and semantically. The major objective of this work is to develop a methodology for interfacing tolerance modeling with boundary representation (B-Rep) based 3D solid model geometry. We will demonstrate that the OOP paradigm is very efficient and flexible for tolerance model representation, which is required within the interactive design process. Six categories of tolerance classes have been developed for size, form, orientation, position, runout and profile, which extend a general tolerance class through inheritance. An instance of the general tolerance class will be initialized when picking a feature or a group of features to tolerance, depending upon feature(s’) characteristics and attributes. To apply a tolerance object the system obtains the 3D geometric data from the solid model using the feature extraction paradigm. When the required tolerance type is selected for modeling, an instance from the specified tolerance type class will be initialized through inheritance from the general feature tolerance class and gathers the necessary information / tolerance data. An intelligent validation engine that supports the modeler is introduced. The engine validates any selected tolerancing activity in two stages. First, it ensures that the selected feature or group of features is suitable for the selected tolerance type. Second, it ensures that the data specified does not lead to over/under-dimensioning. The paper also discusses a prototype system implemented to test the modeler and the validation engine. The results have been very encouraging while testing the system on a number of engineering models.

Agent-Based Distributed Collaborative Sourcing of Stamped Parts

Metal stampings are an important manufactured product. Their production cycle includes the steps of part design, process and tooling design, tooling construction, and production. Each of these activities may be performed within departments of a single manufacturing plant, but more commonly are separated across firms and are widely distributed geographically. To be most effective, this process should be performed concurrently, with considerable flows of information along the supply chain. Research on Agent-based systems shows they are very promising in this type of task as individual agents can wrap particular domain knowledge and analysis algorithms, are always available to respond and are able to autonomously form networks as needed to complete product and process design tasks. In this paper we examine the particular case where alternate suppliers may be selected to supply components to the supply chain. Agents are used to connect the suppliers to the supply chain network. Each supplier firm’s agent understands the firm’s production capabilities, costs and capacity loading, and is able to negotiate with a broker agent representing the stamped part customer. A prototype system is described, and case studies are used to show the benefits of an Agent-based approach to this supply chain problem.

Development of a G-Code Free, STEP-Compliant CNC Lathe

The paper describes a STEP-compliant CNC lathe that demonstrated a G-Code free machining scenario. This research work was conducted in two parts. The first involved retrofitting an existing CNC lathe with a more open platform control system — Compumotor Motion Control system, which is capable of interfacing with other CAPP/CAM programs through languages such as Visual Basic, Visual C++ and Delphi. The control system is programmable using its own motion control language — 6K Motion Control language. A library of 6K functions has been developed to cater for different turning operations. The second part of the research is the development of a “STEPcNC Converter,” which can understand and process STEP-NC codes, and interface with the CNC controller through an interface. It makes use of STEP-NC information such as “Workplan,” “Workingstep,” machining strategy, machining features and cutting tools that is present in a STEP-NC file. The Application Interpreted Model (AIM) of STEP-NC has been used.

An Expert Framework Aide for Determining Optimal Design Models

This paper presents the development of a CAD-based expert framework aide for the decision making on choosing optimal design methods. The proposed framework is based on a comparative study of gradient enhanced meta-models using response surface modeling (RSM) and Kriging techniques, the two most promising meta-modeling techniques studied extensively in design optimization schemes for approximating complex systems. However, current and past research shows that the performance of these methods mandates significant improvements due to the fact that a large number of sample points are needed from within the design space for a considerable accurate model. This makes the designers face a dilemma between accuracy and computational cost. To overcome this so called curse of dimensionality problem, a proper framework with which the models can be validated and its reliability can be evaluated is proposed and established in this research work. Our approach is aimed at forming a GUI-based software framework (utilizing DACE) in MATLAB® that will aid the designers to decide which Meta-model would be most suitable for a certain modeling for design. It will help designers to plan the design of experiments and train the models using the gradient information available at low cost and consequently, validate the model with existing data, as well as produce error analysis graphs and performance criterion charts of all the models for a final decision making. A comparative study of performance of the gradient enhanced RSM and gradient enhanced Kriging models are conducted for six different test equations of various degrees of non-linearity using this proposed framework. A Pro/Engineer® model of a bracket is taken as a test case for the verification of the efficiency and effectiveness of the proposed expert framework as a decision-making tool for designers of engineering products. All the tested Metamodels performed satisfactorily within the specified error margins.