Anti-Collision Controller for Sydney Monorail

Due to ongoing problem to keep the existing Autoilot device on the Sydney Monorail in working order, the Anti-Collision Controller (ACC) was developed and built as a replacement to the customer’s specifications.

Functions performed by the ACC:

  • Measuring the distance to the Monorail in front, based upon the same principle as the Autopilot, i.e. injecting a constant current into the diode rail and measuring the voltage drop. The distance is displayed in metres on the remotely mounted display panel.
  • By evaluating the distance to the train in front, take necessary actions, such as reducing the speed and applying the emergency stop, if required.
  • Transferring the distance information in coded format to the train's PLC.
  • Receiving and processing signals from the magnetic receiver (upper & lower track flags, left & right door zone flags). Transferring the decoded information from the track flags to the train's PLC (station ID, synchronization point, station synchronization point and station reset point).
  • Interlock the door opening function so only the doors on the platform side will be allowed to open.
  • The ACC has a range of built in supervising functions, making sure that any malfunction will not affect the safety of the train.
  • A total of four microcontrollers are used in the project.