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European trains are equipped with a pneumatic braking system that has to respect severe specifications concerning both performances and safety. The pneumatic braking system is composed of hundreds of different pneumatic components that reproduce the prescribed response by a complex logic of pneumatic and mechanical elements. In this paper a tool for a complete simulation of the pneumatic braking system is described, it was developed using the Matlab-Simulink numerical environment.The tool is composed of three different libraries of pneumatic components. The first includes the elementary components such as pipes, orifices, valves and the reservoir. By assembling elementary components, an advanced user can build a customized version of general pneumatic components or plants. Complex components of general use for railway pneumatic brake such as brake cylinders, distributors, pressure transformers and brake valves are available in a second library that can be used to assemble a customized braking plant for a vehicle. The last library is composed of macropneumatic subsystems that reproduce the braking system of a typical railway vehicle. Many common plant layouts are reproduced in this library (freight car, passenger coaches, locomotives, etc.).The pneumatic brake system of a train can be simulated by assembling in a single Matlab-Simulink model the elements of the library.In this paper the main features of this numerical tool and the test procedures developed to validate the software are described. Experimental data have been kindly supplied by Trenitalia SPA and they are referred to several test campaigns managed by Italian railway in order to verify and release existing components of the pneumatic brake.

The Mechatronics and Dynamic Modelling Laboratory of the Department of Industrial Engineering, University of Florence, as a partner of THESAURUS (Italian acronym for ‘TecnicHe per l’Esplorazione Sottomarina Archeologica mediante l’Utilizzo di Robot aUtonomi in Sciami’) project, has developed an innovative low-cost, multirole autonomous underwater vehicle, called Tifone. This article deals with the adopted methodologies for the autonomous underwater vehicle design: in particular, the main focus of this study is related to its propulsion system. According to the expected performances and requirements of THESAURUS project, the vehicle has to maintain good autonomy and efficiency (typical features of an autonomous underwater vehicle), with high manoeuvrability and hovering capabilities, which are more common of remotely operated vehicles. Moreover, cooperative underwater exploration and surveillance involve the use of a swarm of vehicles. In particular, the optimization of costs versus benefits is achieved through the design of a fleet of three multirole vehicles. Each autonomous underwater vehicle has five controlled degrees of freedom, thanks to four thrusters and two propellers: in this article, the preliminary design criteria concerning the vehicle and the design and testing of its actuation system are described

In railway applications, the testing of on-board components is necessary to optimize the efficiency of the systems and to allow high safety levels. In order to reduce the time and the cost of the testing phase, the use of dedicated test rigs is being increased. The current paper summarizes some studies for the realization of a full-scale locomotive roller rig. The main mechanical and control problems that arise in the design of this type of test rig have been highlighted, and in particular, the feasibility of tests with degraded adhesion conditions between the wheel and the rail is simulated.