Abstract
<p>Recent accidents experienced at railway level crossings are pushing researchers to design surveillance systems able to grant safety of passengers and structural integrity of trains at level crossings. The challenge is represented by granting at the same time an appropriate reliability, availability and maintainability degree despite the high safety requirements imposed by the application. The approach proposed in this paper takes into consideration the most common suggested standards used in designing this kind of systems and introduces new general concepts which demystify the use of such standards in actual applications. This paper illustrates the roadmap to be followed in general when designing level crossing monitoring systems, to minimize the risk due to object misdetection occurring on barrier closure when exploiting radar technology.</p><p>A specific surveillance system based on FMCW radar technology was used as a case study, but the approach presented in this paper has a general validity.</p>
Highlights
The design of any system interacting with the signalling infrastructure of railways implies the integration of safety requirements
Different techniques can be exploited for the design of an level crossings (LC) monitoring system, the advantages with respect to the drawbacks of each possible technical solution should be weighted towards the safety constraints before actual implementation
The overall probability of failure on demand (PFD), which corresponds to the probability of missed detection due to the presence of three under threshold target (UTT) in the scene (PMD) is given by the product of the estimated PND and P{to be detected (TTD) in the scene}
Summary
The design of any system interacting with the signalling infrastructure of railways implies the integration of safety requirements. The approaches followed for safe system design derive from the standard in [1] and on minor modifications of previous designs for similar applications, as in [2]-[4] According to these guidelines, software, hardware and communication issues are taken into consideration in granting the needed safety targets. Others as [7]-[9] used the standard approach to safety design trying to exploit reliability block diagram methods or fault tree analysis resulting in a partial problem overview. This kind of approach is important and is a fundamental aspect of a safety design but, in many cases, it is not sufficient: the safety.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
