Benchmarks have long been used to verify and compare the readiness level of different technologies in many application domains. In the field of wearable robots, the lack of a recognized benchmarking methodology is one important impediment that may hamper the efficient translation of research prototypes into actual products. At the same time, an exponentially growing number of research studies are addressing the problem of quantifying the performance of robotic exoskeletons, resulting in a rich and highly heterogeneous picture of methods, variables and protocols. This review aims to organize this information, and identify the most promising performance indicators that can be converted into practical benchmarks. We focus our analysis on lower limb functions, including a wide spectrum of motor skills and performance indicators. We found that, in general, the evaluation of lower limb exoskeletons is still largely focused on straight walking, with poor coverage of most of the basic motor skills that make up the activities of daily life. Our analysis also reveals a clear bias towards generic kinematics and kinetic indicators, in spite of the metrics of human-robot interaction. Based on these results, we identify and discuss a number of promising research directions that may help the community to attain a com-

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Traction and braking systems deeply affect longitudinal train dynamics, especially when an extensive blending phase among different pneumatic, electric and magnetic devices is required. The energy and wear optimisation of longitudinal vehicle dynamics has a crucial economic impact and involves several engineering problems such as wear of braking friction components, energy efficiency, thermal load on components, level of safety under degraded or adhesion conditions (often constrained by the current regulation in force on signalling or other safety-related subsystem). In fact, the application of energy storage systems can lead to an efficiency improvement of at least 10% while, as regards the wear reduction, the improvement due to distributed traction systems and to optimised traction devices can be quantified in about 50%. In this work, an innovative integrated procedure is proposed by the authors to optimise longitudinal train dynamics and traction and braking manoeuvres in terms of both energy and wear. The new approach has been applied to existing test cases and validated with experimental data provided by Breda and, for some components and their homologation process, the results of experimental activities derive from cooperation performed with relevant industrial partners such as Trenitalia and Italcertifer. In particular, simulation results are referred to the simulation tests performed on a high-speed train (Ansaldo Breda Emu V250) and on a tram (Ansaldo Breda Sirio Tram). The proposed approach is based on a modular simulation platform in which the sub-models corresponding to different subsystems can be easily customised, depending on the considered application, on the availability of technical data and on the homologation process of different components.

Basing on strict requirements of portability, low cost and modularity, an assistive device for hand-opening impairment, characterized by an innovative mechanism, has been developed and tested by the authors. This robotic orthosis is designed to be a low-cost and portable hand exoskeleton to assist people with hand-opening impairment in their everyday lives. The mechanism has been especially studied for this kind of applications and presents some interesting features in terms of limited encumbrances and costs. Concerning the hand-opening impairment, the authors have also developed a methodology which, starting from the geometrical characteristics of the patient's hand, properly defines the novel kinematic mechanism that better fits the finger trajectories. The authors have tested and validated the proposed approach by building a functional Hand Exoskeleton System (HES) prototype. The preliminary testing phase of the prototype with a single subject is concluded; currently, a group of subjects is testing the proposed HES methodology in collaboration with a rehabilitation center.

PLEASE SCROLL DOWN FOR ARTICLEFull terms and conditions of use: http://www.tandfonline.com/page/terms-andconditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden.The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Scaled roller rigs used for railway applications play a fundamental role in the development of new technologies and new devices, combining the hardware in the loop (HIL) benefits with the reduction of the economic investments. The main problem of the scaled roller rig with respect to the full scale ones is the improved complexity due to the scaling factors. For this reason, before building the test rig, the development of a software model of the HIL system can be useful to analyse the system behaviour in different operative conditions. One has to consider the multi-body behaviour of the scaled roller rig, the controller and the model of the virtual vehicle, whose dynamics has to be reproduced on the rig. The main purpose of this work is the development of a complete model that satisfies the previous requirements and in particular the performance analysis of the controller and of the dynamical behaviour of the scaled roller rig when some disturbances are simulated with low adhesion conditions. Since the scaled roller rig will be used to simulate degraded adhesion conditions, accurate and realistic wheel-roller contact model also has to be included in the model. The contact model consists of two parts: the contact point detection and the adhesion model. The first part is based on a numerical method described in some previous studies for the wheel-rail case and modified to simulate the three-dimensional contact between revolute surfaces (wheel-roller). The second part consists in the evaluation of the contact forces by means of the Hertz theory for the normal problem and the Kalker theory for the tangential problem. Some numerical tests were performed, in particular low adhesion conditions were simulated, and bogie hunting and dynamical imbalance of the wheelsets were introduced. The tests were devoted to verify the robustness of control system with respect to some of the more frequent disturbances that may influence the roller rig dynamics. In particular we verified that the wheelset imbalance could significantly influence system performance, and to reduce the effect of this disturbance a multistate filter was designed.

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