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Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid–electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used.

A hybrid propulsion system for a passenger car is described and its preliminary design and performance discussed. A gas turbine operating in a controlled on-off mode, a generator, a battery pack, an inverter, and an electric motor constitute the power system, with an electronic vehicle management unit supervising the system for control and regulation. Road simulation tests are presented, based on standard ECC driving mission cycles. The turbogas performance might be improved adopting ceramic blades, with a possible increase of the TIT (turbine inlet temperature), and a consequent increase of its efficiency. The paper reports on the first results of a study in progress, within a joint research program between the University of Roma 1 “La Sapienza” and the Italian Research Centre of ENEA-Casaccia.

Although tissue and cell manipulation nowadays is a common task in biomedical analysis, there are still many different ways to accomplish it, most of which are still not sufficiently general, inexpensive, accurate, efficient or effective. Several problems arise both for in vivo or in vitro analysis, such as the maximum overall size of the device and the gripper jaws (like in minimally-invasive open biopsy) or very limited manipulating capability, degrees of freedom or dexterity (like in tissues or cell-handling operations). This paper presents a new approach to tissue and cell manipulation, which employs a conceptually new conjugate surfaces flexure hinge (CSFH) silicon MEMS-based technology micro-gripper that solves most of the above-mentioned problems. The article describes all of the phases of the development, including topology conception, structural design, simulation, construction, actuation testing and in vitro observation. The latter phase deals with the assessment of the function capability, which consists of taking a series of in vitro images by optical microscopy. They offer a direct morphological comparison between the gripper and a variety of tissues.

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The Low Emission Turbogas Hybrid Vehicle Concept-Preiiminary Simulation and Vehicle PackagingTíie paper presents a comprehensive review of the gas turbine hybrid vehicle (GTHV) under development at the University of Roma "Sapienza." A GHTV is an electric vehicle (traction entirely electric on 1 or 2 axles) equipped with a small turbogas operating as a range extender and -when needed-as a recharger for other auxiliaries. After a brief review of the history of the GTHV technology, a few configurations proposed in the past by different Authors are described and critically analyzed. Then, a complete feasibility assessment of a prototype configuration of a GTHV is presented and discussed in detail. Two possible implementations are studied: one for a small city car (peak power 4-8 kW) and one for a sport GT or passenger sedan (50-100 kW). All issues related to the system and component design, packaging, identification of the "optimal" hybridization ratio, performance of the conversion chain (gas turbine + batteries + electrical motor), kinetic energy recovery systems (KERS), mechanical and electric storage devices (flywheels, capacitors, advanced batteries), monitoring and control logic, compliance with the European vehicular ECE emission regulations, are explicitly addressed. One of the most important results of this analysis is though that there are several "nearly optimal" solutions and the final choice for a possible future industrialization would be dictated by manufacturing, commercial or marketing considerations. It because not only the system performance, but also the absolute and relative sizes (i.e., nameplate power) of the turbines and of the battery package depend substantially on the type of driving mission the car is required to perform. In the paper, both theoretical and practical issues are addressed, and on the basis of the analysis of the existing state of the art, it is argued that the GTHV is an environmentally friendly, technically and economically feasible product based on mature components. Assoc. Editor: Kevin M. Lyons. Moreover, a hybrid vehicle can easily switch from its "gasoline" to its "electric" mode, at least for a limited operational range: this "mixed operation" increases the net mileage and releases a substantially lower amount of pollutants over the vehicle lifetime. The most popular hybrid vehicles (HV) are mostly passenger hybrid cars equipped with a traditional ICE and an electric motor (EM) coupled in parallel. The thermal engine is sized, with some exceptions, for the average power, and the surplus power needed during rapid acceleration phases is supplied by the electric motor. Hybrid Configurations.There are several hybrid concepts, differing by the type of the coupling between the electric and the thermal engine, and by the control logic that supervises the energy flows. The main distinction is between series-and parallel hybrids (Fig. 1), parallel designs being currently more popular. In a series design, the intemal combustion engine is not mechanically connected to the powe...

Abstract. For years, the interest of the UDR1 research group has focused on the development of a Hybrid Series (HS) vehicle, different from the standard one thanks to the use of a Gas Turbine set (GT) as a thermal engine. The reason for this choice resides in the opportunity to reduce weight and dimensions, in comparison to a traditional Internal Combustion Engine (ICE). It is not possible to use the GT engine set directly for the vehicle traction, therefore the UDR1 HS configuration shows the GT set connected with the electric generator only. The result is that the traction is purely electric. The resulting engine configuration is a commonly defined Hybrid Series. Many efforts are spent in the definition of a generic scientific method to define the correct ratio (Degree of Hybridization) between the installed power of the battery pack and that of the GT electric generator, which simultaneously guarantees the life of the battery pack and the capacity of the vehicle to complete a common mission without lack of energy or stopping. This article reports a method to define the power ratio between battery pack and GT generator, applied to a recent commission for the development of a mini city bus.

SUMMARYThe object of this study is a theoretical and experimental analysis of a new hybrid propulsion system for a passenger sedan in which the thermal engine is a small gas turbine set. Some preliminary results on the possibility of replacing the conventional ICE of a hybrid 'series' configuration by a turbogas were presented and discussed in previous papers by the same authors: several possible designs were examined under both a thermodynamic and an operative point of view. This paper presents a summary of the project and constitutes an attempt to put things in a proper engineering perspective: the technical feasibility of the project is assessed via a calculation of the required mission loads, a preliminary design of the most important elements of the propulsive system, the choice of the mission control strategy and the implementation of a numerical system simulator. The experiments that provided a verification for the assumed component efficiencies were carried out, in cooperation with the Research Centre of ENEACasaccia, on an ELLIOTT TA-45 group. Our results, though only preliminary, allow for a direct comparison between a GT-hybrid vehicle and a modern diesel car, and indicate that the GT-hybrid may be actually a competitor for the FC-powered vehicle concept. Our 'optimal' configuration is a combination of a 100 kg battery pack and two turbogas set of 5 and 16 kW, respectively.