STC, manufacturer of the EMTRAC signal-priority system, has integrated Galileo satellite navigation with EMTRAC equipment installed in transit and emergency vehicles.
Similar to GPS, Galileo is the new European navigation system and will have 24 operational satellites at full capacity.
The Galileo system commenced limited initial service on December 15, 2016—and EMTRAC is the first confirmed Galileo-capable signal-priority system.
(Learn More about the EMTRAC Emergency Vehicle Preemption (EVP) and Transit Signal Priority (TSP), courtesy of EMTRAC and YouTube)
Signal priority systems are installed in traffic networks throughout North America, and they enable equipped transit and emergency vehicles to request green signals through equipped intersections, reducing travel time while increasing efficiency.
With this addition, the EMTRAC system simultaneously tracks Galileo-system satellites along with the GPS and GLONASS constellations, increasing the overall number of satellites used to determine vehicle positions.
The EMTRAC system also utilizes dead-reckoning navigation through multiple 3D inertial sensors to maintain accuracy in difficult urban conditions, such as urban canyons, tunnels, and multi-level highways.
According to STC President Brad Cross, integration of the Galileo navigation system immediately increases accuracy, and performance will continue to improve in the coming years.
“As more satellites are added to the Galileo constellation, we expect the EMTRAC system to be more reliable than ever in areas where sky view is obstructed,” Cross said.
STC recently conducted a controlled test of the EMTRAC system. During the test, an EMTRAC-equipped vehicle successfully interpreted detection zones and transmitted priority requests to a simulated intersection utilizing only Galileo satellites.
(Find out about safety features of the EMTRAC system for both transit rail vehicles and right-of-way rail workers, courtesy of EMTRAC and YouTube)
“We believe this to be the first test of its kind in North America,” Cross said.
While high precision is not necessary for many signal priority scenarios, Cross says there are specific situations where it is essential.
“Precision positioning is critical for applications like rail-worker safety and lane-specific signal response.”
(See an example of Galileo satellites already in service of the on-board train positioning system. Courtesy of European GNSS Agency and YouTube)
Similar technology is also used on EMTRAC transit-rail products, which alert train operators and wayside workers when there’s potential for unsafe conditions.
“We need to be able to report which track a particular train or worker is on at a rail yard where there may be 10 or 15 sets of tracks, side by side,” Cross said.
Cross added that all future deliveries for EMTRAC vehicle equipment will include Galileo capability, and this equipment will be compatible with existing EMTRAC equipment, making upgrades to installed wayside equipment unnecessary.
STC has manufactured the EMTRAC system for over 25 years, and it is used by traffic, transit, rail and first-response agencies in the United States, Canada, and Mexico.
