MAKING IT ALL MESH
WHILE the trainset and tracks are readily visible to casual observers, constructing a modern railway system is actually a very complicated task. Railways, be it anything from a monorail to high-speed rail, comprise many interactive systems, meaning there’s plenty of scope for things to go wrong.
For example, the rails, other than supporting train wheels, can also carry electrical currents which could be part of the signalling system. Other parts of the rail (such as systems that incorporate a third rail) could be part of the traction power system, and this could generate electromagnetic waves that could interfere with other parts of the signalling or communications system.
Other than the traction power system, there is a wide array of equipment to ensure the operability of any railway, and these include radio and telephonic voice communications; control, command and monitoring functions; and routing of power, gas and water supplies, along with a host of cables. All these vie for the tight and limited space in stations, on platforms, in depots, on bridges and embankments, and in tunnels. There are also other constraints that have to be taken into account, such as the bandwidth used for communications and data channels, with data for customer information, CCTV transmissions, and fire detection and intruder alarm systems all jostling for the capacity offered by telecommunications networks.
Lastly, the many types of rolling stock have to be compatible with the infrastructure. Ordering trainsets is not a matter of going through the catalogue and picking something, as each train – on, for example, the MRT – has to be custom-built for each line. In view of the many demands imposed by the need for safety, reliability, security and efficiency, each system has to be designed with not just its own functionality in mind but also those of the other systems, and how all these interact with each other. The task of ensuring that all these seemingly disparate systems work in harmony with each other in all possible scenarios, including accidents, emergencies, and extreme demands, is called systems integration (SI).
SI expertise is one of the most sought after engineering skills in the rail industry anywhere in the world, including in Malaysia where we are still playing catch up.