This paper aims to provide an overview of the present status of research in pantograph–overhead line interaction and to outline future research challenges. A review of currently used modelling and simulation approaches is provided, also including hybrid simulation, and emerging trends are outlined. Then, line testing methods for the certification of pantographs and catenaries are described and the limitations of measuring methods now in use are highlighted. Issues related to the reliability and availability of the pantograph–overhead line system and to life-cycle costs are then covered in the paper, particularly concerning wear and other damage phenomena and condition monitoring solutions enabling the efficient maintenance of the system. Pantograph aerodynamics and active control of pantographs are finally identified as two emerging trends of research. For both subjects, a review of problems currently at stake and of future research directions is provided.

This paper discusses the possibility of using computational fluid dynamics (CFD) to assess the influence of aerodynamic forces (aerodynamic uplift) on the mean contact force acting between a pantograph and the contact wire. The analysis consists of experimental tests and CFD simulations, performed in both wind tunnel and on-track scenarios. A method for the computation of the aerodynamic uplift and for the assessment of the contact force imbalance between the leading and trailing collectors is proposed. The method is based on the virtual work principle, and exploits both the numerical forces resulting from CFD analysis, and the Jacobian terms obtained from a kinematic analysis of the pantograph. The proposed model takes into account stationary phenomena, and it is fully validated by means of experimental results.

The aim of the paper is to highlight the influence of the deformable modes of the collector of high-speed pantograph on the quality of current collection. The study was first conducted with an experimental survey on a few collectors for high-speed pantographs, in order to determine their modal parameters and dynamic responses in relation with their structures. Subsequently, a comparison with finite-element modelling was performed, comparing the calculated natural frequencies and mode shapes with the measured ones. Finally, the influence of the deformable modes on the dynamic interaction between pantograph and catenary was analysed, using a simulation model developed in previous works, incorporating the deformable modes of the collector into the model of the pantograph, by means of the experimentally defined modal parameters. The objective of this analysis was to investigate, in particular, the effect of the contact wire irregularity on the contact force up to 100 Hz.

Small-scale production is relying more and more on personalization and flexibility as an innovation key for success in response to market needs such as diversification of consumer preferences and/or greater regulatory pressure. This can be possible thanks to assembly lines dynamically adaptable to new production requirements, easily reconfigurable and reprogrammable to any change in the production line. In such new automated production lines, where traditional automation is not applicable, human and robot collaboration can be established, giving birth to a kind of industrial craftsmanship. The idea at the base of this work is to take advantage of collaborative robotics by using the robots as other generic industrial tools. To overcome the need of complex programming, identified in the literature as one of the main issues preventing cobot diffusion into industrial environments, the paper proposes an approach for simplifying the programming process while still maintaining high flexibility through a pyramidal parametrized approach exploiting cobot collaborative features. An Interactive Refinement Programming procedure is described and validated through a real test case performed as a pilot in the Building Automation department of ABB in Vittuone (Milan, Italy). The key novel ingredients in this approach are a first translation phase, carried out by engineers of production processes who convert the sequence of assembly operations into a preliminary code built as a sequence of robot operations, followed by an on-line correction carried out by non-expert users who can interact with the machine to define the input parameters to make the robotic code runnable. The users in this second step do not need any competence in programming robotic code. Moreover, from an economic point of view, a standardized way of assessing the convenience of the robotic investment is proposed. Both economic and technical results highlight improvements in comparison to the traditional automation approach, demonstrating the possibility to open new further opportunities for collaborative robots when small/medium batch sizes are involved.

This paper describes a diagnostic system for overhead line monitoring; it is based on the measurement of collector accelerations, and aimed at improving current scheduled methods for catenary and pantograph maintenance, making condition-based maintenance possible. The proposed setup is inexpensive and easy to install on in-service commercial trains. Meaningful indicators of pantograph/catenary interactions are obtained by the processing and analysis of data on collector accelerations; summarized values are computed in real-time during the train run and compared with alarm limits.