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Systems integration: navigating increasing complexity

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Guest author: Nassar Majothi, director of the rail specialist services group at WSP London.

All too often, major infrastructure programmes are subject to significant complications, which can delay delivery and breach the budget. In the rail sector, larger and more complex programmes are expected to deliver greater outputs in the face of limited resources. This means a step change in management capability is more important than ever.

To meet the demands of increasing urbanisation and population growth, the global railway sector has seen significant investment over the last few decades, both to build new and to upgrade existing infrastructure. Developing management approaches that provide more certainty in the delivery of economic infrastructure is key to instilling confidence from government and other investors.

Railway programmes, which are characteristically lengthy and complex, share delivery difficulties common with other major economic infrastructure. That they tend to be hundreds of kilometres long, cover varied geographies and environments, and usually require extensive line-side furniture to integrate with trains and the modern digital consumer, only adds to the challenges facing today’s railway programmes.

The innovation in programme management and engineering management capabilities needed to manage this complexity has, for the most part, not kept up with the pace and scale of delivery challenges facing major programmes. However, systems integration (SI) is an increasingly popular solution, which seeks to solve a complex problem by dividing the whole into smaller parts.

Beginning at the end

From efficiently coordinating technical development of missile defence programmes in the 1950s to the customer-led delivery of today’s major programmes, SI is a fundamentally pragmatic approach to managing complexity.

An idea for a new product, system or service is often proposed in terms of the final desired outcome, whether that’s meeting consumer needs, transporting people, saving time, or transforming a place. The SI approach begins with this end in mind, demanding that the operational outcome, the end user benefits and even how a system of people, processes and technology can achieve those outcomes, be determined from the outset.

Breaking down the grand idea into pieces that are understandable and deliverable, while maintaining the desired outcome for the end user, is the domain of the systems integrator.

SI structures the delivery of complex rail infrastructure programmes by enabling a holistic approach that can be practically applied throughout the programme or system lifecycle. This focus on delivering the desired outcome, be it increased railway capacity or another whole-system measure, is a step beyond the traditional ‘divide and conquer’ approach favoured by programme management, where delivery is broken down into discrete parts. SI gives a more holistic view, supporting decision making that priortises effort, and providing a ‘line of sight’ through the fog of complexity.

In the UK, WSP has been applying systems approaches to programme delivery since the mid-2000s, beginning with the Victoria line upgrade (where the author worked as a systems engineer and WSP, through a previous acquisition, had provided project and programme management services) and the East London line. These projects were the genesis of a tool that is still used today – SI:D3 (System Integration: Develop the strategy, Define the system, Deliver integration). It can be adjusted according to complexity and risk, and as a result, continues to be applied to a wide range of programmes in the UK and internationally.

Clear vision from the start

SI can connect the overarching vision with the need for technical development and delivery at the front end of a given programme. This, often ‘fuzzy’ front end usually includes aspirational objectives, which are sometimes politically driven, and can be difficult to translate into operationally and technically tangible outputs.

Experience has shown that the earlier that an SI approach is implemented, the greater is the liklihood of getting to the point of clarity and defining the journey of transformation. On projects such as the Thameslink Programme, Northern Hub and TfL’s Deep Tube Upgrade Programme, WSP has found it is the only approach that works. On all of these projects, interactive system architecture diagrams have been used to understand the overall transformation, including that of people’s roles in the system, and the construction phasing.

For example, one of WSP’s many roles on the Thameslink Programme was as part of its systems integration team. The company’s System Migration Plan (SMP) choreographed the intricate dance that all parties needed to perform so they could deliver this enormous upgrade without disruption and ensure the railway could remain in use throughout. It defined a series of configuration states – changes to the railway associated with greatest risk – establishing them as the primary milestones in the SMP. A series of systems architectures – physical, geographical and operational – linked to the configuration states defined in the SMP, described in detail how the railway needed to change.

WSP’s systems engineering and integration team is embedded across projects on Northern Programmes, where it manages the technical design integration activities across its entire portfolio. This has included facilitating design integration between engineering disciplines during design, development and construction, which has assured compliance to the project requirements, standards and procedures. Using an Action Tracker database, the team logs and tracks actions from design reviews and records the status of design documents to manage requirements and outputs on key projects such as North West Electrification.

Thameslink – London Bridge station. (Thomas Graham)

Holistic system design

When conducting system design, it is important to consider how the design fits into the whole and how one element impacts another.

This is not always obvious. For example, a goal may be to run trains closer together to improve capacity. This would, of course, involve designing the signalling control system accordingly. However, plans would also have to consider the rolling stock braking capability, platform re-occupation, track layout and additional demands on the traction power supply system.

Careful system design, modelling and simulation are also essential in designing a safe and high-performing tunnel ventilation system. After all, in order to consider the impacts of heating and cooling on passenger safety and comfort, one must also consider the impacts on the signalling system, train aerodynamics, train regulation for both efficient running and safe separation of trains, walking and escape routes, installation, logistics and the reliability of assets.

The railway systems requirements that were developed on High Speed 2 (Phase 1) were embedded into HS2’s standards and mandated for use. A unique railway project for the UK, these requirements had to surpass the current industry standards.

For example, track alignment criteria for 400km/h line speeds required a review of track alignment design criteria, including a thorough review of international standards and best practice examples of high-speed rail from around the world. This ensured that the resultant designs provide for future technology and consumer changes and meet the key project requirements of journey time and capacity, augmented with a series of models that demonstrate that the high capacity and speeds needed can be realised without compromising passenger comfort and safety.

The system of systems

SI can also be applied at route level, bringing together multiple projects and programmes across a control period for the coordination of ongoing benefits realisation, through both asset owner and train franchise.

The Greater West Programme Industry Systems Integration (TGW ISI) pulls together disparate and discrete projects to update and electrify both a railway built by the Victorians and train services that run from the west of England to London. This programme, estimated to be worth £5.6 billion in total, represents the biggest rail enhancements portfolio in the UK and introduces new classes of rolling stock in the form of Bombardier Class 387 commuter trains and Intercity Express Programme (IEP) Class 800/802 units from Hitachi.

SI was used to manage big changes to the programme, and a unique collaborative approach was adopted to account for all consequences and deliver every service change on time. WSP will continue this successful approach in its new role as industry system integrator for the East Coast main line and Midland main line.

East London Line – Hoxton Station. (John Sturrock)

The future of systems integration

SI capability will need to mature quickly if it is to handle the software, IT and connectivity elements that have become a feature of our more complex railway systems. Software is less tangible and harder to visualise than physical assets, and software developers work to a more iterative lifecycle, so the problem of software components not talking to each other is not always apparent until the testing and commissioning phase, when the stakes are higher. SI labs could reduce this risk by re-creating the physical, software and data assets through the programme lifecycle.

BIM tools and methods are now common and showing practical value. A robust SI approach could develop an end-to-end digital project that unites each lifecycle stage using tools that map requirements to designs, schedules and contracts in a highly visual and accessible format.

To get the return on investment for major railway projects, investors will want to maximise ridership opportunities and revenue streams. To this end, a programme needs to deliver a system that is aligned with the needs and wants of people at the initial transport planning phase, even detailing how people will interact with the technology. Accordingly, human-centred design is a focus for WSP, which is already building a human factors team and sees it as central to the development of a ‘future ready’ railway.

With the rapid trend towards global urbanisation there is a greater role for rail as an agent of mobility, and global investment in rail solutions is expected to reflect this.

Rail’s green credentials continue to provide a good option for modal change that reduces emissions and, with urban land use planning enabling over-site developments that integrate with smart cities, highways and automated vehicles, rail is also a good platform for the next generation of integrated transport. It follows, then, that more requirements will be put on railway projects, making the technological and operational challenges greater still.

The scene is set for the system integrator to play a larger role in infrastructure development, ultimately determining the success or failure of programme delivery.

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  1. This is a great article and one of the best I have read to reflect the Systems Thinking approach in Rail industry. Certainly in such multidisciplinary programs Systems Integration and in general Systems Engineering from being in passenger seat and following the program management, must move to the driving seat to lead the program along with classic program and project management approaches. Good job Nassar.


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