Worldwide, the number of megacities has been growing rapidly for several decades. Even today, half of the world’s population lives in cities, and urbanization is set to continue. This will produce a growing need for urban mobility which can only be covered by new transport concepts. For this reason, work is being carried out across the globe on driverless electric shuttle buses for future local public transport. They permit fast and convenient transportation, are highly efficient and environmentally friendly. The HEAT (“Hamburg Electric Autonomous Transportation”) project is setting new standards. In the last expansion phase in 2021, Hamburger Hochbahn AG, operator off the underground system and large parts of the bus services in Hamburg, will be using driverless shuttles in regular, everyday road traffic. As development partner, IAV is providing the automated transport vehicles.
IAV has been working on the innovative technology of highly automated shuttles for several years. “We quickly realized we need to integrate the infrastructure into the concept if we want to provide a cost-effective, comprehensive solution that is suitable for everyday use in the near future”, explains Benedikt Schonlau, head of department in the Vehicle Integrated Functions division at IAV. Instead of packing all of the automation intelligence into the vehicle, it will be efficiently split between the shuttle and the periphery. “Everyone will do the jobs they can do best”, Schonlau says. The focus is on automated driving at Level 5 which, by common definition, requires no human intervention. For lower levels of automation, where it is imperative for a driver to stay on board for emergency situations, a purely vehicle-based approach would be sufficient.
Interconnection of vehicle and infrastructure
The shuttle concept IAV helped to develop was first implemented as part of the statefunded OTS 1.0 project. Within the research consortium, IAV was responsible for developing the vehicle. In particular, this involved realizing the automated driving functions and the interfaces connecting the vehicle with the periphery. Project partner Siemens developed the intelligent infrastructure needed for the system. For example, this relays traffic light signals or information on traffic situations and road users, e. g. at intersections along the route, directly to the shuttle. The data are processed there and taken into account for controlling the vehicle. The test operation of OTS 1.0 on the premises of Siemens AG in Munich-Perlach delivered valuable findings, specifically in respect of the concept’s suitability for everyday life.
Public transport comes with stringent requirements
“OTS 1.0 demonstrated the fundamental suitability of our approach. With HEAT, we are now taking the next step”, Schonlau explains. The ambitious project is so far the only one of its kind in Germany: Whereas the route used in OTS 1.0 only took the vehicle across closedoff terrain, HEAT is being implemented on public roads in traffic moving at up to 50 km/h. “This means the automated control system must take account of absolutely all influences from other road users, such as pedestrians, cyclists and motorists, including behavior which doesn’t necessarily always comply with the rules”, Schonlau says, commenting on the project’s particular challenges.
Focus on type approval
The technology behind the electric shuttle bus developed by IAV specifically for HEAT is based on the layout that proved successful in the OTS 1.0 project. The vehicle’s sensor system for automated driving mainly involves radar and lidar. Cameras are used as well, but as the detection rates of today’s cameras still fall short of the needs for autonomous driving, digital databases and digital communication are used for the visual aspects, such as traffic-light phases, lane and roadway line markings or road signs.
As in the OTS 1.0 project, cooperation partner Siemens is providing the route with the necessary active and passive sensors. “Although automated Level 5 vehicles cannot yet be homologated under current legislation, we are expecting that exceptional permission will let us get started. However, by the end of the project period, our joint aim is to have developed the overall system to such a level that it will definitely be able to obtain proper homologation”, Schonlau says, outlining the project’s goal.
In this context, one main focus is on reliably getting information to the vehicle. According to Schonlau, a major challenge in providing information lies in connecting the analog and digital systems. For instance, a digital twin of the analog road must be produced and maintained for the project. All information that can be reliably provided for the digital twin via digital communication systems no longer needs to be acquired by the vehicle on an analog basis. Traffic lights are a good example of the digital twin. All of today’s traffic lights use softwarebased, digital state machines. These activate analog light signals, the state of which must be identified and reconstructed by driver assist systems in today’s vehicles involving a complex process. A digital traffic light twin in contrast communicates the topology and current signal states to vehicles, providing far greater reliability, even at the concept stage. In the HEAT project, this digital communication concept will help to provide a key element in the overall safety concept.
The safety concept is backed up by a control center operated by Hamburger Hochbahn. Via a data link, the operator there can intervene in the driving function and safely stop the shuttle bus. However, this is only done in exceptional situations, such as if a storm suddenly limits vehicle sensor system reach to such an extent that it is no longer possible to continue the journey. Communication with shuttle passengers is also possible from the control center, providing the ability to respond to specific emergency situations. Examples of these vary widely, such as a passenger suddenly experiencing serious health problems in the vehicle.
Beacon project for the ITS World Congress
The HEAT project will run until 2021. Testing is structured in stages so that experience gathered can in each case be channeled into the next project step. The route will be extended on a gradual basis, the level of automation increased and top speed taken to 50 km/h. In the first phase, testing will start on a relatively short route, without passengers and with a vehicle driver who will be able to take action whenever necessary. The next phase will see passengers taken on board for the first time. In the final phase in 2021, the shuttle will go into fully automated operation without any vehicle attendant. The route will then include twelve sets of traffic lights and eight changes in direction.
Given its overall functionality, demo operation under the HEAT project will set a new standard the world over. As a beacon project for automated passenger transport, it will also be a highlight at the World Congress for Intelligent Transport Systems (ITS World Congress) being held in Hamburg in 2021. Attracting over 10,000 participants, this key event rotates between Europe, the Asia Pacific region and the Americas, returning to Europe every three years. Focal topics of the 2021 World Congress include automated and connected driving, intelligent logistics, mobility services and intelligent parking – areas of future mobility which IAV is already doing much to shape through research and development services, such as the electric shuttles for the OTS 1.0 and HEAT projects.
OTS 1.0 Optimized Transport System Based on Self-Driving Electric Vehicles
In the “Optimized Transport System Partners:
Based on Self-Driving Electric Vehicles – OTS 1.0” project, an autonomous and electric vehicle is being developed for local public transport (road) which is to run in a designated testing site as part of demonstrating operation in Munich-Perlach in mid-2018.
The aim of the project is to examine concrete approaches to future mobility concepts (infrastructure and vehicles ) and look at their business models. Consideration is being given to the legal aspects of implementing this system and matters of social acceptance.
- Siemens AG, Munich University of Technology, Chair of Traffic Engineering
- IAV GmbH
- IKEM – Institute for Climate Protection, Energy and Mobility
- UTB Projektmanagement GmbH
- Emm! Mobility solutions