"Randall Train Automation Controller" (RTAC) is part of a suite of free-software for model railroad computer control with the main goal of running trains automatically and performing other event-based automation. It uses JMRI to interface with a model railroad’s command station.

The “Conductor” server uses an event-based script to drive the computer automation.
The “RTAC” Android software displays the system status on a network of Android tablets.

The system was designed and is actively used to drive the automation of the Randall Museum's model railroad in San Francisco.