India’s metro rail network has expanded rapidly over the past decade. Currently, over 1,000 km of the metro network is operational in the country. Key metro rail systems include the Delhi metro, Mumbai metro, Kolkata metro, Bengaluru metro, Chennai metro, Kochi metro, Lucknow metro, Nagpur metro and Pune metro. Metro rail systems provide significant advantages in urban transportation by promoting energy efficiency, environmental sustainability and cost-effectiveness. They consume only one-fifth of the energy per passenger, generate no direct air pollution and produce minimal noise. Additionally, metro systems occupy no road space if they are underground and only about 2.6 metres in width if elevated, making them highly space-efficient in congested urban areas.
Notable advancements
Deploying modern technology
A recent notable advancement in metro rail systems is the integration of artificial intelligence (AI), which is being used for crew scheduling, train scheduling, predictive maintenance, and calculating train demand and traffic flow. Additionally, internet of things (IoT) applications, along with big data and blockchain, are being used for health monitoring of point machines. Smart passenger information display systems now provide real-time updates on train details and service changes. Standardised protocols allow various systems to communicate effectively, thereby facilitating smooth operations across different lines and different networks. AI and machine learning (ML) algorithms are being used to analyse images of metro rail infrastructure, such as tracks, tunnels or overhead lines, to detect anomalies or
potential defects.
Building information modelling (BIM) and digital twins are two interconnected technologies revolutionising the design, construction and operations of metro rail infrastructure. The Nagpur metro has extensively used BIM technology for its design and construction. Digital twin technology creates a virtual replica of a physical asset, which is continuously updated with data from sensors and other sources. This allows for real-time monitoring, performance analysis and predictive maintenance.
Towards automation
Modern metro systems rely on a combination of communication technologies, including radio systems, fibre optics and data networks, to ensure seamless communication between trains, control centres and maintenance teams.
In any metro system, rolling stock is classified by its grade of automation (GoA), indicating the level of automation for train operations. Metro systems are increasingly incorporating GoA-3 and GoA-4 levels of automation, signifying the transition towards driverless and fully automated operations. GoA-3 refers to driverless train operations, where the train is automatically driven, with an attendant on board to handle emergencies. GoA-4 represents unattended train operation, meaning the train is fully automated with no staff on board. The integration of IoT, AI and ML into metro rail rolling stock marks a significant stride towards a smarter, more efficient and safer urban transit system.
Increasing focus on multimodal connectivity
The integration of multimodal transport systems, by connecting airports, railway stations, bus terminals and ride-sharing services, is aimed at enhancing accessibility, reducing congestion and improving overall mobility by allowing seamless transfers between different modes of transportation. By being the first metro system in the country with an integrated multimodal transport system, the Kochi metro provides end-to-end connectivity.
Tracking sustainability initiatives
Energy-efficient technologies and practices are also being implemented, such as regenerative braking systems and solar-powered stations. This results in reduced operational costs and contributes to environmental sustainability. Additionally, leveraging automatic train operation (ATO) speed profiles helps save 8-10 per cent of energy, optimising metro train movement to reduce energy consumption. This is achieved by designing ATO speed profiles that minimise acceleration and braking. The Kochi metro has achieved 51 per cent energy neutrality by generating a significant portion of its power needs through solar energy.
Core functionality and signalling operations
Signalling systems ensure safe and efficient train movement by managing train spacing, speed limits and route selection. The communications-based train control (CBTC) system is a signalling system that utilises telecommunications between train and track equipment to regulate traffic and control infrastructure. First, the carbon controller calculates the position of the train using trackside beacons and the train’s odometer, and this position is sent by radio to the zone controller. Following this, the zone controller calculates the moving authority limit (MAL) and sends it to the vehicles. The zone controller also sends the position of all trains to the automatic train supervision (ATS) system to be displayed. Finally, the carborne controller calculates its braking curve so that the MAL is never exceeded and the train moves along the curve.
Another scenario involves non-equipped CBTC vehicles. These vehicles do not communicate but occupy the track circuit. The status of the track circuit position is communicated to the zone controller, which in turn communicates to the following CBTC train. The train, which is equipped with CBTC, will calculate its MAL.
Advanced systems are being designed to prevent collisions and other safety incidents on the metro rail network. For instance, an indigenous automatic train protection system, known as the train collision avoidance system, has been developed by Indian Railways in collaboration with an Indian manufacturer. Another advanced signalling system is the European Train Control System, which is being applied in the regional rapid transit system (RRTS).
Growing indigenisation
India’s metro rail sector has seen significant indigenisation over the past 10-15 years. BEML Limited is a leading manufacturer of metro rolling stock in the country. Bharat Electronics Limited (BEL) has developed an indigenous CBTC system in collaboration with the Delhi Metro Rail Corporation. This system aims to enable unmanned metro and train operations for the first time in India. BEL has also indigenously developed a platform screen door, which has been installed at the Duhai station of the Delhi-Meerut RRTS network. These platform screen doors act as a safety barrier between the passengers on the platform and the train.
Lifts and escalators, power supply systems (third rail/overhead equipment), supervisory control and data acquisition systems, fire protection and suppression systems, and tunnel ventilation systems are also being manufactured in India.
The incorporation of indigenous systems in metro rails has numerous benefits. However, the development and deployment of these metro rail components incur high costs. One of the major challenges is integration with existing systems, as it requires significant modifications in the existing system. It remains important to ensure that the technologies being used meet international standards and are compatible with other systems. Another challenge is securing funding for indigenous technology. The gap between workforce skill development and training also continues to hamper the uptake of these systems. Gaining public acceptance and trust in new technology is another significant challenge.
Breaking ground with India’s first water metro
Operated by Kochi Metro Rail Limited (KMRL), the Kochi Water Metro is the first of its kind in India, which integrates water transport with the city’s urban mobility systems. The project is partly operational, comprising 15 routes. Its fleet consists of 78 battery-operated electric hybrid boats and 38 jetties.
The metro project has been planned in three phases. Phase I and its extension have already been completed, connecting Aluva to Thrippunithura with 25 stations spanning 28 km. Meanwhile, construction work is in progress under Phase II, consisting of 11 stations (11.2 route km), and Phase III is under planning, consisting of 19 stations (25 route km).
Cybersecurity measures pick up pace
With the increasing reliance on technology for efficient metro operations, advanced cybersecurity solutions are critical for identifying potential threats. To this end, KMRL has taken several measures. For instance, critical infrastructures have been developed as per the Indian Computer Emergency Response Team’s guidelines. The cloud infrastructure features advanced data encryption protocols to protect data both at rest and in transit, ensuring the confidentiality and integrity of metro rail information. Automatic fare collection gates are undergoing a thorough audit, and relevant patches have been deployed at key areas, strengthening the defence against external threats.
In sum
As metro rail systems continue to expand globally, the need for standardised signalling and telecommunication protocols has increased substantially. This standardisation is crucial for ensuring interoperability, safety and operational efficiency across diverse urban networks. The evolution of these systems reflects the sector’s ongoing commitment to enhancing safety standards, optimising network performance and ensuring reliable service to passengers.
Based on a presentation and remarks by a representative from KMRL at a recent Indian Infrastructure conference
