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Battery/Ultracapacitor (UC) Hybrid Energy Storage Systems (HESS) for Electric Vehicles (EVs) have been frequently proposed in the literature to increase battery cycle life. The HESS consists of a Power Management Strategy (PMS) and an Energy Management Strategy (EMS). Existing EMS are quite empirical, such as setting constant target UC energy levels regardless of load. This work presents an improved complete HESS management strategy. The EMS involves a more comprehensive method of setting the target UC energy level using a speed-dependent band. This allows the UC to achieve two goals – contain sufficient energy for future accelerations and have sufficient space for capturing energy from future regenerative braking – without knowledge of the future drive profile. The PMS involves a speed-dependent battery power limit, which also achieves two goals – better UC utilization and allowing the battery to supply the steady state power. Simulations show existing works cannot achieve the four goals simultaneously unless their UCs are sized twice as large compared to the proposed rule-based HESS. In addition, the proposed HESS extends battery cycle life by up to 42% compared to a battery-only system. Lastly, a reduced-scale experiment was built to show that the proposed HESS is able to run in real-time.

The rapid development of additive manufacturing technology provides a more flexible and efficient manufacturing solution for the high value-added parts with a complex topology. However, the poor surface finish poses a major obstacle for the wide application of the additively manufactured components when their functionality and tolerance are benchmarked with those produced by the conventional process. In selective laser melting, visible pattern and texture of the printed layers and unmolten particles cannot be avoided although research works have been conducted to improve the surface finish by optimising the selective laser melting strategy and process parameters. Therefore, a dedicated post-processing technique is generally required to improve the surface finish of the additively manufactured products in terms of various levels of geometric complexity. In this study, a vibration-assisted conformal polishing tool is developed to finish a representative v-groove structure fabricated by selective laser melting. Experiments are conducted to investigate the effects of abrasive size and polishing time on the improvement in surface roughness. The developed technique in this paper can be applied to finish the additively manufactured internal structures such as honeycomb structure and irregular holes that have linear projection along a single axis.

Platform-based product family has been proven an effective strategy to economically provide wide market coverage. However, two practical platform design issues need to be properly handled: (1) commonized components require over-design of features that drives capability waste and additional costs with regard to the lower end product variants, and (2) commonization pattern of components is constrained by couplings of the base platform architecture. This research attempts to present a generic approach for the optimal platform design that treats commonization of components in a hierarchic manner under hybrid modular architecture. Three major sections are included: (1) identification of hidden interface costs defined by the architectural couplings, (2) modeling of hierarchic sharing relationship of commonized components across product variants, and (3) configuration of the hierarchic components platform for the lowest total production cost. Finally, a family of cordless drills targeting a series of rated output torques is employed to demonstrate the proposed approach.

This paper presents a product structure model with a semantic representation technique that make the product structure extensible for developing product lifecycle management (PLM) systems that is flexible for make-to-order environment. In the make-to-order business context, each product could have a number of variants with slightly different constitutions to fulfill different customer requirements. All the variants of a family have common characteristics and each variant has its specific features. A master-variant pattern is proposed for building the product structure model to explicitly represent common characteristics and specific features of individual variants. The model is capable of enforcing the consistency of a family structure and its variant structure, supporting multiple product views, and facilitating the business processes. A semantic representation technique is developed that enables entity attributes to be defined and entities to be categorized in a neutral and semantic format. As a result, entity attributes and entity categorization can be redefined easily with its configurable capability for different requirements of the PLM systems. An XML-based language is developed for semantically representing entities and entity categories. A prototype as a proof-of-concept system is presented to illustrate the capability of the proposed extensible product structure model.

Concurrently engineered product development requires effective inter-functional communication and knowledge sharing across multidisciplinary teams and heterogeneous processes. This paper presents a semantics-enabled approach to the integration of knowledge maps with design process configurations to support more meaningful communication and seamless collaboration between cross-functional teams and concurrent workflows in new product introduction (NPI) processes. The proposed approach focuses on: explicit and formalized process description and configuration of NPI activities; process knowledge capture and reuse through knowledge maps; integration of knowledge maps into design process configurations; and ontology-based process model mapping and knowledge sharing to support seamless process collaboration. It thereby contributes to the development of the next generation concurrent engineering methodologies in order to achieve NPI process advances for meaningful inter-functional communication and collaboration. The approach has been implemented in a software prototype to provide the concurrently engineered product development with the capabilities of semantic process description and configuration, knowledge reuse, and process collaboration.

In the modern global economy, companies are facing ever-increasing challenges for short time-to-market to enter into the market early, for reduced time-to-volume to occupy the market quickly, and for decreased time-to-profit to get return from market shortly. Product lifecycle management (PLM) is recognized as one of the key leading technologies to facilitate companies to overcome these challenges, which will offer companies a new way to rapidly plan, organize, manage, measure, and deliver new products or services much faster, better, and cheaper in an integrated way. Following this trend, this study proposes a full scenario of technology solutions for PLM based on the complete analysis of business drivers, industry requirements, limit of current solution, and recent state-of-the-art review in the domain related to PLM. Potential industrial impact of the developed PLM technology solutions is analyzed. It is hoped that the proposed PLM technology solutions will form the frontier basis for further research, development, and application of PLM systems to quickly adapt to the dynamic changing market for industry companies to pursue the most advanced competitiveness.

In today's competitive business environment, a product development is the result of a team effort involving a multi-disciplinary group of designers, manufacturers, even supplier and customer representatives. Effective collaboration among various groups is impor tant for reducing cost and product development time. Hence, the aim of our study is to develop a WWW-based collaborative system for integrated design and manufacturing. The proposed system is composed of three modules—collaboration, design, and manufacturing. This paper focuses on its collaboration module and the design module. Its manufacturing module is discussed in References [1] and [2]. The collaboration module is WWW-based platform-independent and provides a virtual collaborative environment for a part designer to perform on-line communication with customers and manufacturers via the Internet. All participants in the collaborative environment can view, and manipulate the solid model of the design part as well as discuss their concerns on-line interactively. The design module utilizes the design by features approach to construct a part. Traditional design by features systems restrict the designer to a fixed set of pre defined features provided by the system vendor. The proposed design module includes an extension mechanism for designers to create user-defined features and an evaluation mechanism for designers to perform manufacturability evaluation. The design module is able to generate a very complicated user-defined feature and to provide feedback concerning potential manufacturing problems in the early design stage. Both proposed modules have been implemented on a Sun workstation using the ACIS geometric modeler, C++, and JAVA.