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The aim of this study is to design and implement a virtual reality bicycle system based on a functional-based mechatronic design approach. The development of virtual reality technologies with haptic systems demands a proper integration of the involved disciplines to provide immerse experiences for users. The proposed design approach provides a formal manner to gather the subsystems in the mechatronic device. The developed system is divided in a Virtual Reality System (VRS) and a Physical System (PS) for the design process. The former includes an interactive virtual environment in which an Avatar is animated using a simple kinematic bicycle model. The latter includes an adapted mountain bicycle with haptic feedback mechanisms to interact with the user and to produce the corresponding inputs for the bicycle model. Both systems are integrated by a control behavior system that works under two operation modes, where the user carries out virtual tours and gets feedbacks from a stereoscopic display system, audio cues, and haptic mechanisms. A multibody simulation validates the consistency and the integration of the physical system. In addition, a set of experimental results show the performance of instrumentation elements, control strategies, and feedback mechanisms, to provide the user with an immersive experience in the virtual environment. A brief survey was carried out to assess the opinion of users about the virtual bicycle tours, providing feedback for future improvements. The different designed modules and sub-systems allow modifying and enhancing the VRS without major modifications of the PS, or allow enhancing the physical platform without affecting the functionality of the virtual environment. • Integration of several technologies for a virtual reality system using a VDI 2206 guideline. • Modular configuration for enhancement of the system. • Low latency times obtained, allowing a fluid an immersive experience. • Control-behavior subsystem to configure the operating mode of the system. • Proportional and ADRC strategies for haptic feedback. [ABSTRACT FROM AUTHOR]

Inspection of offshore plants or harsh marine environments, requires underwater vehicles with high autonomy, performances and maneuverability. These features are deeply affected by the design of propulsion system. An accurate design of the propulsion system, involves the modelling of the response of propellers. In this work a reconfigurable propulsion layout for an inspection vehicle is presented. Performances of the proposed solution are evaluated and compared respect to the conventional one which is currently installed on benchmark test vehicle (the MARTA AUV from University of Florence). Proposed layout exhibit superior maneuvering performances that should be useful for the inspection of offshore plants and more generally for harsh operational conditions. [ABSTRACT FROM AUTHOR]

Abstract: With the goal to investigate the relation of shape and function of single cells or clusters of cells in a 3-dimensional (3-D) microenvironment, we present a novel platform technology to create arrays of microwells on polystyrene (PS) chips for hosting cells in a local microenvironment characterized by controlled shape and surface chemistry. The micro-3-D cell culturing combines 2-dimensional chemical patterning with topographical microstructuring presenting to the cells a local 3-D host structure. Microwells of controlled dimensions were produced by a two-step replication process, based on standard microfabrication of Si, replica molding into poly(dimethylsiloxane), and hot embossing of PS. This allowed the production of large numbers of microstructured surfaces with high reproducibility and fidelity of replication. Using inverted micro contact printing, the plateau surface between the microwells was successfully passivated to block adsorption of proteins and prevent cell attachment by transfer of a graft-copolymer, poly(l-lysine)-g-poly(ethylene glycol). The surface inside the microwells was subsequently modified by spontaneous adsorption of proteins or functionalized PLL-g-PEG/PEG-X (X=biotin or specific, cell-interactive peptide) to elicit specific responses inside the wells. Preliminary cell experiments demonstrated the functionality of such a device to host single epithelial cells (MDCK II) inside the functionalized microwells and thus to control their 3-D shape. This novel platform is useful for fundamental cell-biological studies and applications in the area of cell-based sensing. [Copyright &y& Elsevier]

This paper is a general overview of the Skipper project, run at Blaise Pascal University between 1996 and 2002. The main goal of the Skipper project was to demonstrate the applicability of skeleton-based parallel programming techniques to the fast prototyping of reactive vision applications. This project has produced several versions of a full-fledged integrated parallel programming environment (PPE). These PPEs have been used to implement realistic vision applications, such as road following or vehicle tracking for assisted driving, on embedded parallel platforms embarked on semi-autonomous vehicles. All versions of Skipper share a common front-end and repertoire of skeletons––presented in previous papers––but differ in the techniques used for implementing skeletons. This paper focuses on these implementation issues, by making a comparative survey, according to a set of four criteria (efficiency, expressivity, portability, predictability), of these implementation techniques. It also gives an account of the lessons we have learned, both when dealing with these implementation issues and when using the resulting tools for prototyping vision applications. [Copyright &y& Elsevier]

This article presents a general modelling framework dedicated to the short-term planning of energy systems, which supports the fast prototyping of optimization models. Due to the need for its applicability to practical problem instances, the methodology is based on a generic Mixed Integer Linear Programming (MILP) formulation. In addition, a specific graphical formalism called Extended Resource Task Network (ERTN) is proposed for the configuration step, which enables the modelling of any type of system and the automatic instantiation of the optimization models. The value of implementing such a tool is demonstrated through the modelling, operational planning and performance evaluation of a Combined Heat and Power (CHP) plant that participates in the French Day-ahead electricity market. Indeed, while real-time control of utility plants plays an important role in ensuring the balance between production and needs, forecasting and planning these production systems is becoming increasingly necessary to make them more energy and economically efficient. The case study shows, on the one hand the potentialities of the modelling approach through the ability to achieve rapid development and implementation of complex systems, and on the other hand significant opportunities to improve the site's economic profitability as well as its environmental impact. • Generic modelling framework for the short-term planning of production systems. • Rapid prototyping with a block-oriented graphical modelling tool (ERTN formalism). • Multi-modal and non-linear behaviour equipment modelling. • Automatic instantiation of the generic underlying MILP planning model. • Software components for the development of Energy Management System for CHP plants. [ABSTRACT FROM AUTHOR]

A common problem in networking research and development is the duplicate effort of writing simulation and implementation code of routing protocols. This can be avoided by reusing simulation code in real prototyping and in production environments. In ns-3, emulation mode can be used to run simulation models of routing and Software Defined Networking (SDN) protocols on top of real L2 interfaces such as Ethernet and Wi-Fi. Although this feature is already available, the additional packet processing involved degrades the performance of the nodes and limits the amount of network traffic that can be processed. Our proposal to overcome this performance bottleneck consists in moving the data plane processing operations to outside of the ns-3 process, running such operations natively in the host Operating System (OS). Two approaches are proposed: (a) running the data plane in user space (DPU); (b) running the data plane in kernel space (DPK). Both approaches support the emulation of one or multiple nodes per emulation host machine. The experimental results show that the DPU and DPK approaches significantly improve the throughput by respectively 4.9 and 19 times when compared against traditional ns-3 emulation of a single node. For multiple nodes, the DPK approach further improves the throughput by as much as 23 times. The amount of code reuse is high – e.g., for the routing protocols used in this paper, only 1.4% and 11% of extra code is required to benefit from the performance improvements achieved respectively by the DPK and DPU approaches. [ABSTRACT FROM AUTHOR]