Ostrava - OBUs with many functions
Complete fleet deployment
Highlights of the project
- Full fleet equipment - 650 vehicles (trams, buses, trolleybuses)
- Public transport priority system (OBUs) using SREM and SSEM messages, including coordinated stay at stop.
- Several C-ROADS use cases - warning about public transport vehicle at stop, one-way track warning, collision warning, etc.
- OBU is fully integrated to our board computer EPIS 4.0
- Many sensors and access to the CAN bus or the data from the tachograph units
- Powerful Wi-Fi for passengers
V2X use-cases
Several dangerous situations can occur in a daily operation of public transport. People are running to catch the bus, tram tracks cross with roads, vehicles can crash each other. This is where V2X helps in Ostrava. The use-cases, which are currently implemented are:
- Warning of car drivers when a public transport vehicle is at potentially dangerous stop (e.g., a tram stop in the middle of the road).
- Warning of car drivers when a tram track crosses or enters the road without traffic lights.
- Warning of other tram drivers about a slippery rails.
- Warning about potential collisions of trams (rear-end collisions) – video from testing is below
- Checking presence on one-way track.
- Public transport priority.
Public transport priority with coordinated stay at stop
In Ostrava, coordinated stay at stop for public transport vehicles is in a daily operation. Using our technology, the public transport company saves money every day. The vehicle will leave the stop only after it receives a command from the traffic light controller. This guarantees that the vehicle will pass on green without stopping.
Read more about this solution here.
Powerful Wi-Fi for passengers
The OBU unit in the vehicle provides the passengers an internet access using integrated Wi-Fi access point and internal LTE connection. The speed of LTE allows the users fast internet connection. For the best user experience, the access point is tightly integrated with a mobile application of the public transport company.
To ensure fair-user policy, the access point is equipped with a captive portal and speed limiting features.
Detailed vehicle state logging - CAN and tachograph
To provide other vehicles correct information about the state of the vehicle, the OBU should not rely only on a GPS. The public transport vehicle typically can provide detailed information about the movement using:
- CAN bus (we support FMS standard and SAE J1939),
- Tachograph for vehicles where it is available.
This way our units also collect important information about the ride of the vehicles. In addition to connection to vehicle buses, the unit also features accelerometer and gyroscope.
Collisition warning based on V2X
We have successfully tested a collision warning system based on V2X. As described above, to be ably to rely on information received from other vehicles, the information must be precise. Therefore, each vehicle uses an advanced data fusion algorithm for combining data from GPS, tachograph, accelerometer and internal digital maps. This way we able to achieve high precision of the position.
Using precise information and detailed mathematical model of the vehicle, the unit is able to correctly calculate the braking distance and hence also assess an imminent collision warning. If a potential collision is detected, accoustic warning is played.
See the video above.