The EMTRAC system is capable of handling conditional factors in a number of methods—depending on your available capabilities. These methods include:
- Connection to Onboard Transit Computer: The transit computer outputs conditional status to the EMTRAC Vehicle Computer Unit (VCU). For example, the transit computer determines that the bus is five-or-more minutes behind schedule and outputs this status to the EMTRAC VCU, which requests priority until the bus status is once again within the pre-defined time frame.
- EMTRAC Priority Detector Determines Status: The intersection-based Priority Detector calculates the conditional status and responds accordingly. For example, if a bus on Route 180 has requested priority at a given intersection within the last five minutes, the Priority Detector does not forward priority requests from Route 180-buses during the pre-defined time frame.
- AVL System Determines Status: EMTRAC Central Monitor (or third-party transit AVL system) determines vehicle and/or intersection states and outputs that data to the intersection-based Priority Detector, which carries out (or withholds) priority requests as a result.
For information about how the EMTRAC system is used to generate conditional priority in Brampton, Ontario, please read the Transit Applications and EMTRAC System white paper.