SMRT has completed a major two-year upgrade of Bishan Depot, an S$7 million project that uses automation and new digital systems to double the facility’s monthly train overhaul capacity. The enhanced depot can now overhaul four trains a month, up from two previously, marking a significant improvement in the efficiency of Singapore’s oldest train maintenance facility.
Automation-led upgrade boosts efficiency
The 39-year-old Bishan Depot serves the North-South Line and now operates with advanced technology that streamlines maintenance work. SMRT announced on 21 November that new autonomous vehicles and robotic systems have reduced workforce needs by 30 per cent. The project, known as Depot 4.0, began in July and aims to shape the design and upgrade future depots across the rail network.
SMRT said the expansion of Singapore’s rail system and the introduction of more trains require larger maintenance capabilities at a time when the workforce is shrinking and ageing. With the upgrade now complete, all train overhaul work will be centralised at Bishan Depot, which is roughly the size of 55 football fields. This shift allows Tuas West Depot to focus on other maintenance tasks.
Trains undergo overhauls at 500,000 km and 1 million km milestones, with different components restored at each stage. The enhanced depot was officially launched by SMRT chairman Seah Moon Ming, with Acting Transport Minister Jeffrey Siow as the guest of honour. Former transport minister Khaw Boon Wan also attended the event.
Depot 4.0 is a joint effort with Chinese train manufacturer CRRC Qingdao Sifang, which has supplied trains for the North-South, East-West and Thomson-East Coast lines, and will also supply trains for the upcoming Cross Island Line. Automation has helped remove bottlenecks in the overhaul workflow, cutting overhaul time by half and enabling the depot to increase output without expanding its physical space.
Robots replace cranes and support heavy-duty tasks
A major feature of the upgrade is the replacement of traditional overhead cranes with 11 rail-guided vehicles. These autonomous robots transport heavy train components such as bogie frames, each carrying loads of up to five tonnes. A six-car train contains 12 bogies, making efficient movement crucial to overhaul operations. Previously, components often sat idle while waiting for crane access.
The rail-guided vehicles have height-adjustable platforms that allow staff to work more comfortably and with less strain. SMRT said the robots’ controlled movements improve workplace safety by reducing the risks associated with manual lifting and overhead crane operations.
The depot also introduced a new bogie disassembly and assembly system that automates the separation of bogie frames from wheelsets and their reassembly. This task previously relied heavily on cranes and required repeated manual adjustments. The new system connects directly to the autonomous vehicles, which deliver and collect bogie frames from workstations. As a result, workforce needs have dropped from 4 engineers to 1, and the time required to complete each bogie has been reduced.
Driverless vehicles and new cleaning technology support safer, faster work
Two automated guided vehicles now transport smaller train components such as traction motors and tread brake units. These items were once moved manually or by forklifts, often causing delays as workers waited for forklift availability. The automated vehicles can carry up to one tonne and navigate the depot using on-board sensors, stopping safely when near obstacles or people. Staff can also set routes through a control panel. According to SMRT, this change has reduced queue times, improved ergonomics, and reduced physical strain.
The depot has also introduced a dry-ice cleaning machine to replace traditional water cleaning methods. This technology reduces water usage, eliminates drying time for components, and removes the risk of slipping on wet floors.
On 21 November, SMRT also launched its Kaizen Centre, a facility showcasing staff-driven initiatives to improve productivity and safety. Kaizen refers to the philosophy of achieving steady, meaningful improvements. Mr Seah stated that since 2018, employees have completed nearly 9,000 projects, generating about S$700 million in savings over the past 7 years. “With these savings, we can also do more for the community,” he said.
As part of these efforts, SMRT will partner with SG Enable to distribute 18,000 Nets FlashPay cards to people with disabilities and their caregivers. Each card will contain a stored value of S$38 in honour of SMRT’s 38th anniversary.
The Kaizen Centre highlights initiatives in transformation, safety, sustainability and productivity. Depot 4.0 is one example, while Project Overwatch uses artificial intelligence to monitor train services. The centre is meant mainly for SMRT staff and is not open to the public. However, it will host invited visitors from government agencies, educational institutions, rail operators and industry partners.
