Repoint project develops fault tolerant railway switch

Conventional railway switches guide trains from one track to another by sliding a pair of tapering rails horizontally. Repoint uses a lift and move mechanism, which includes a passive lock for when the points are in place. This is combined with a stub-switch type layout, which is said to offer advantages in many situations. The switch is further claimed to be ‘fault-tolerant’, continuing to work when two of the three actuators that control the movement of the points have failed.

Research published by the team in Railway Engineering Science describes the team’s development of a digital twin which has been used to show that the design meets and exceeds requirements for speed and performance.

The research investigated the performance of the switch using a novel method for simulating track system behaviour, which combines rail bending with physics-based models of actuators and control systems. The simulation scenarios included one of power failure to four of the six motors that drive the actuators, and showed that a single actuator is capable lifting and moving the points to the desired position.