Focus Sensors
Advancing Rail Safety through Intelligent Fibre Sensing

Precise monitoring of assets such as tracks and wheels is essential to rail safety. Focus Sensors leverages the power of fibre-optic networks and sensors to monitor and deliver continuous insights into track stability, wheel health, early warning signs of failure and even the presence of intruders.

The idea was born from a simple conversation between two friends, Dr Ed Austin and Dr Weizhong Zhao, in a pub in Winchester. They wondered why the optical fibres already installed for communications couldn’t be used as sensors to improve the safety and efficiency of rail infrastructure. This thought sparked two years of experimentation in a drafty garage, culminating in the creation of Indus, a distributed sensing system that provides rail operators with continuous visibility into track and infrastructure health. They later built the Indus Platform, a cloud-based system that turns data from Indus into real-time insights that operators can act upon.

“Our unique, patented, fibre-monitoring system opens the door to vast and continuous railway monitoring, solving problems for our customers,” says Dr Austin, co-founder and managing director.

Indus combines fibre optic movement sensing (FOMS) and acoustic sensing (FOAS) to interpret how the track, its support structure and passing trains behave in real-time. By comparing how the track responds over time, the system detects subtle changes that would otherwise go unnoticed.

Focus Sensors’ technology has been deployed in multiple locations around the world. It works with major operators, including Network Rail, ProRail and ADIF. Each Indus station monitors up to 80 kilometres of track with one-metre resolution. Installation is typically completed within four hours without requiring access to the track.
Its collaboration with Network Rail High Speed on the HS1 route demonstrated how optical signals could be translated into actionable insight. Over the course of six months, more than 11 million measurements were taken along 38 kilometres of track. It revealed issues in switch and crossing components by showing abnormal vibration patterns and elevated track instability at the failing component. Eventual successful repair reduced the instability, as expected. Furthermore, Indus uncovered areas of increased track instability 50m from the faulty component, providing a probable reason for the failure.

Focus Sensors’ Indus has proven effective in detecting wheel defects, one of the most persistent maintenance challenges. Rather than relying on fixed-point measuring equipment, Indus reads wheel impact behaviour from passing trains anywhere on the monitored line. This allows operators to identify damage early, schedule maintenance and prevent costly damage to trains and rails.

The Indus platform identifies component issues, subsidence, drainage failure and embankment instability by marking areas of interest where track instability exceeds expected thresholds. In one instance, gradual subsidence was detected months before visual inspection or measurement trains recorded any sign of change, allowing maintenance teams to act before service disruption.

All readings are sent directly to the Indus Platform, where billions of data points are transformed into easy-to-read maps, timelines and alerts. It highlights areas that require attention and can predict problems such as subsidence or drainage faults. With no equipment installation required on trains or tracks, monitoring becomes seamless, eliminating service interruptions and reducing workers’ exposure to risks.

Its security applications are an advantage. During a live trial at the Global Centre of Rail Excellence, Indus distinguished between movement inside and outside the track boundary by locating footsteps within an eight-by-one square metre zone. Even in the presence of over 200 people, the system only triggered alarms when movement occurred inside the defined area. This precision reduces false alerts and enhances security without requiring additional sensors or patrols.

Indus is transforming ordinary communication fibres into intelligent sensing networks, creating a growing network of awareness that listens, learns and protects. Focus Sensors is redefining the future of railway monitoring using optical fibres.