Problem

CN was nearing completion of a project to enable remote operation of moveable rail bridges within Metro Vancouver, and was looking for a means to support operators in safely opening and closing the spans while taking into account rail, marine and personnel traffic. Furthermore, bridge movements and traffic events were being recorded in paper-based format, thereby limiting the ability to operate in a transparent and coordinated manner.

Solution

An intranet web app was implemented to provide users with a clear understanding of current rail, marine and personnel traffic, as well as open/close state, at each bridge. An operator can obtain control of one or more bridges simultaneously, and is guided through workflows consisting of one or more steps, when scheduling traffic events and before being in a position to open/close the bridge. Traffic event conflict detection and resolution features help ensure the bridge is operated safely. Visual and audible notifications occur at configurable intervals prior to the occurrence of key traffic events, to help ensure the bridge is opened/closed when required.

Notable aspects of this project include:

  • Implementation of an intranet web app based on ASP.NET, together with jQuery and KnockoutJS for front-end client interactivity,
  • Implementation of operator sessions to restrict bridge control to a single operator at a time, and handle concurrency conflicts,
  • Leveraging the Service Worker API available in modern web browsers to provide offline access to most recently known traffic event details,
  • Implementation of desktop app, wrapping the web app, to facilitate consistent deployment of Operator Workflow System (OWS) in a dual-monitor configuration.

Interface 48 delivered this project in collaboration with PBX Engineering.