Autonomous bus trials in Japan are using emergency vehicle detection (EVD) audio technology from Massachusetts-based Cerence AI.

The trials are being run by AS Mobi (Advanced Smart Mobility) within its autonomous bus platform across Japan.

Cerence EVD detects approaching emergency vehicles, including ambulances, police cars and fire engines. Emergency vehicle awareness is an important challenge for autonomous transportation systems operating on public roads. Emergency vehicles are often audible before they are visible, particularly in dense urban environments, around intersections or when visibility is limited. An ambulance approaching from behind traffic or a fire engine navigating through a congested city corridor may be heard well before it enters a vehicle’s field of view.

AS Mobi’s autonomous mobility help address critical transportation problems in Japan, including an aging population and driver shortages. Taking place across multiple regions in Japan, the field trials represent Cerence AI’s first autonomous bus programme in the country and reflect AS Mobi’s broader vision to scale autonomous transportation services, with future commercial deployment targeted for 2027. The collaboration also marks the first deployment of Cerence EVD using exterior microphones.

Cerence EVD uses audio AI technology to detect approaching ambulances, police vehicles and fire engines, helping autonomous vehicles take appropriate action. The technology supports more than 1500 sirens across 47 countries and is designed to distinguish emergency sirens from traffic noise and other environmental sounds. EVD complements cameras, radar, lidar and other sensing technologies used in autonomous driving systems, providing an additional layer of environmental awareness.

“Our focus is addressing transportation challenges through safe and reliable autonomous mobility,” said Masaya Segawa, president at AS Mobi. “Emergency vehicle awareness is an important capability for autonomous bus operations, and our collaboration with Cerence AI supports our efforts to advance transportation services that are safer, more accessible and better equipped for the dynamic challenges of real-world environments.”

Christian Mentz from Cerence AI (www.cerence.ai) added: “As autonomous mobility moves from controlled testing environments to real-world transportation services, vehicles need a broader understanding of their surroundings. When emergency responders are navigating through traffic, every moment matters. EVD helps autonomous systems identify approaching ambulances, fire engines and police vehicles early and take appropriate action, supporting better transportation systems and safer communities.”

To learn more about Cerence EVD, visit www.cerence.com/products/audio-ai#evd.

Cerence is headquartered in Burlington, Massachusetts, with operations globally.

AS Mobi (www.as-mobi.com), founded in 2014 in collaboration with the University of Tokyo, develops autonomous driving technology for trucks and buses to address driver shortages and the revitalisation of regional transportation in Japan.