Here, the eight most interesting facts of the project are explained briefly and concisely: for a quick overview of our project.
Facts
Installation of Roadside Units
In the TEMPUS test field, around 65 traffic lights are equipped with roadside units (RSUs) that enable communication between infrastructure and vehicles. A roadside unit acts either only as a transmitter or as a transmitter and receiver at the same time and can be used in different ways depending on the use case.
Operating only as a transmitter, a RSU sends information about the current signal state of a traffic light (SPaT) and road topology of the respective intersection (MAP). This information supports automated vehicles in safely crossing an intersection.
As a transmitter and receiver at the same time, a RSU with return channel can additionally receive data from vehicles and forward it to the traffic signal system for processing. This functionality is needed, for example, to accelerate public transport buses or to prioritize emergency vehicles. Due to the RSU with feedback channel the vehicles can register at the traffic signal system and influence the switching phases, i.e. request green phases.
Transmission Technologies (ITSG5 and CV2X)
WLAN and cellular-based near-field communication technologies are being tested which allows a great flexibility and variety in application testing.
Automated vehicles need safety-critical information within a fraction of a second, especially at intersections, to be able to react appropriately. Currently, only near-field communication via ITSG5 (WLAN-based) and CV2X (cellular-based) guarantees sufficiently short latencies. In principle, both technologies offer the same range of functions and differ only in the transmission technology used. Due to the lack of standardization, it is not yet possible to predict which technology will prevail in Europe in the future. Non-time-critical applications, such as public transport acceleration, can also be handled via the classic 5G mobile network in the future.
Data Transmitted to the Vehicles (SPaT/MAP)
Via roadside units, information on road topology (MAP) and on the current phase of the traffic signal system (SPaT) is sent to automated vehicles.
A MAP file is a digital image of the respective intersection, in which route informations are also stored. This enables automated vehicles to locate themselves at the intersection and assign the valid signal image to the respective lane.
The SPaT file (Signal Phase and Timing) contains the current signal of a traffic light, which can be transmitted digitally by the roadside unit. In addition to the visible perception by vehicle cameras, a second redundant signal is thus available to the automated vehicles. This is needed, for example, if the camera image cannot be relied on in poor visibility conditions. Furthermore, the SPaT file can be used to provide the vehicle with the predicted remaining time of the signal, which can be used to adjust the driving behavior in the course of the intersection approach.
By transmitting both file types, the complex situation of an intersection is made comprehensible to the automated vehicle and reliable and safe travel across the intersection is made possible.
Cross-Territorial Test Field
Our test field covers both the urban area and the surrounding region. This allows us to test our use cases across a wide range of traffic situations and circumstances.
The term “cross-territorial” implies that several municipalities or administrative levels are involved in the project. For TEMPUS it regards the City of Munich responsible for the urban area as well as the Bavarian State Construction Directorate responsible for the surrounding area of Munich. As different road types are assigned to the two administrative levels (for example urban roads, federal roads, highways), the use cases can be tested under a wide variety of traffic situations and conditions within the framework of TEMPUS. It is also crucial for the creation of traffic regulation strategies to closely cooperate with the authorities beyond the city boundaries.
HD-Map of the Entire Test Field
A high precision and realistic 3D model is being created for the complete road network of the cross-territorial test field, consisting of urban roads, federal highways and freeways. This allows automated and connected vehicles, as an example, to detect their own location on the road map and plan their maneuvers. Due to their deviation of up to several meters, conventional GPS solutions cannot provide the required accuracy. The HD-map is available to interested companies for testing purposes on request.
Across all Road User
Applications will be implemented on individual and public transport and the behavior of and interaction with non-motorized road users will be investigated.
Thus, all road users are considered and a holistic improvement of the traffic situation can be ensured.
Mobility Data Space (MDM)
Via the national Mobility Data Marketplace (MDM), we publish traffic data as well as the municipal traffic strategies developed in TEMPUS.
The MDM is an online portal providing a wide variety of traffic data. As a neutral B2B platform, it sets standards for data exchange and offers a rich database for third parties and private service providers. By publishing the data collected in TEMPUS, they are also available to third parties and can be used for free for future developments. For example, vehicle manufacturers and navigation service providers can take advantage of the traffic strategies created and integrate them into their routing system.
Real-Life Testing
Testing on public roads in real-life, i.e., in realistic traffic situations, allows us to effectively improve and adapt to real-life conditions.
Testing in real-life traffic can depict various incidents of daily traffic and thus contribute to improving the technology.