How fast, how big and how luxuriously equipped does a vehicle have to be for transporting people or transporting goods in large cities? In our opinion, very small, simple vehicles designed for a maximum of 60-80 km/h are sufficient for many applications.
The combination of these features is ideal for electric vehicles, because it is about the interplay of weight and energy efficiency. The simpler and lighter the vehicle, the smaller, lighter and thus cheaper the batteries. This formula presents completely new challenges for the vehicle developers, which in the ACM project are met by the team of Roding Automobile GmbH, with many years of experience in the highly complex automotive light construction sector.
With a hybrid chassis made of aluminium and fiber composite materials, the basis for a very light vehicle body is laid. In addition to the weight, particular attention is also paid to the safety of the vehicle occupants. A solid base made of aluminum contains important components such as the batteries. The reinforced passenger compartment made of fiber composites CRP/GFRP protects the vehicle occupants.
Thanks to a special arrangement of the seats for driver and passengers, despite the small vehicle dimensions, a comfortable seating environment is achieved in the vehicle. An innovative swivel seat facilitates the entry and exit of the centrally located driver.
The company Plexiweiss is developing a new door concept from transparent plastic for the ACM CITY. The large, translucent doors not only have a significant weight advantage over conventional glazing and door systems, but also allow a comfortable entry into the vehicle and provide a completely new feeling inside the vehicle.
In the course of the overall ACM project, Plexiweiss is testing new production processes and is thus able to produce such an innovative and weight-optimized door concept economically for the electric and small vehicle market – taking into account all necessary safety aspects for future passengers.
The battery system consists of individual modules, which are combined into a total battery system. The unique feature is that these modules can be removed manually from the underbody of the vehicle. This opens up new possibilities for quick "charging" of the vehicle. The battery swap can be carried out manually or with appropriate mechanical assistance. The individual modules are intrinsically safe and inactive. They can only be used in the vehicle. In addition to the module changeover, the vehicle battery can also be charged conventionally by cable in the vehicle as an overall system.
Battery swapping stations are available for fast supply of freshly charged battery modules. These stations have lockable compartments in which the individual modules are loaded. The exchange begins with the driver's authentication at the station. This will in each case free the compartments in which the used modules can be returned, and then open compartments with fully loaded modules, which are then integrated into the vehicle. The battery exchange stations offer an attractive and space-saving possibility for municipalities and companies to build charging infrastructures and can also take over network functions.
The challenge for the ESK researchers is to open up the ICT architecture for different usage concepts, while ensuring the reliability of safety-relevant driving functions.
The core element of the ICT architecture is a central control unit, which can fulfill safety- and non-safety-critical functions and serves as an interface for telematics services and distributed driver assistance systems.
The protection of automotive software systems is made possible by the modeling of the communication behavior and the application logic. Interfaces are tested and the interplay of distributed components and services are considered. The modular models allow for high reusability.
To reduce complexity in the vehicle, Siemens is developing an embedded ICT platform with the vehicle architecture RACE (Reliable Automation and Control Environment), which allows software-based driver functions to be installed. Thus, the standardized RACE hardware platform takes the place of a dedicated function-specific control unit hardware. This allows a vehicle to be retrofitted with configurations, selected functions or even the full functionality. In addition, this technology meets all today's and future requirements for highly-automated and autonomous driving.
The simple, fast and inexpensive integration of predefined and new driving functions is made possible by RACE by means of open, standardized software. Compared to dedicated functional control units, fewer hardware components and less wiring are required; Sensors and actuators can be used several times for various functions. The use of the RACE platform in the ACM CITY reduces the need for hardware and at the same time creates the prerequisite for a large configuration diversity for driving functions. RACE fulfills high safety and reliability standards (ISO262262), including fault-tolerant behavior, and enables both plug-and-play capability and failure-free fault injections.
On the dashboard, the driver is informed of all the information concerning the condition of the vehicle. This includes information such as speed, battery charge status and remaining range. Warnings or error messages of the vehicle are also presented clearly for the driver.
An infotainment platform is provided to the passenger in the ACM CITY. With this, he can look at the current route, get more detailed information about sights along the route or surf the Internet.
On the vehicle, displays can be installed based on EPD technology. With this technology, information and advertising content can be displayed saving lots of energy because energy is only consumed when the shown content changes. Through communication of all vehicles via geopositioning, both regional and global content can be shown on the displays.
The focus of remoso GmbH in the ACM project is the networking of all the individual technologies of the respective project partners into an intelligent overall system in the vehicle, across all involved persons, vehicles and entities.
Also in development is a billing process that spans all fields of application. The costs are centrally and automatically recorded, categorized, and can then be provided for all stakeholders in the value creation chain.
Complex software solutions are developed for the simple and intuitive use of the mobility system by the end user. The goal is to make the service processes user-friendly and to ensure the maximum efficiency and utilization of the entire fleet. In addition, by being linked to an innovative advertising system, individual advertising control based on time and GPS position is made possible on the external displays of the vehicle.
PEM of RWTH Aachen University
As part of the overall ACM project, the Chair of Production Engineering of E-Mobility Components (PEM) at RWTH Aachen University will be responsible for the development of the pilot vehicles. The structure of the vehicles is linked to research questions in three central areas of action, which are to be answered within the framework of the project. These research questions are:
1.) Realization of an integrated adjustment planning for body components
2.) Development of a procedure for the measurement of components with subsequent creation of compensating elements on the 3D printer to simplify vehicle assembly
3.) Construction of modular assembly devices, with the aim of reducing installation costs and planning costs by 50% compared to current systems
In order to answer these questions, the vehicle construction offers suitable use cases, for example in the areas of the body panels for adjustment concepts or the interior assembly for device concepts. The developed solutions can be implemented, tested and validated by the pilot vehicles and incorporated into the later vehicles of the construction program as lessons learned. Within the scope of the overall project, this subproject is intended to make an important contribution to the further development of electric mobility in Germany, in particular by focusing on small-scale solutions.
Thanks to the installation of its own electric utility vehicles, StreetScooter GmbH can draw on many years of experience in the design of assembly lines and, above all, in the design of vehicles for assembly. Since the first purpose design prototype, StreetScooter has emphasized the cost-efficient production of the vehicles. This know-how is used within the framework of the ACM project to ensure the correct installation of the vehicle. At the same time, direct support is provided for planning the assembly line in order to optimize the associated assembly costs. Supporting the construction of the prototypes serves to verify the concepts and offers valuable insights regarding the possible series production of the electric vehicles developed in the project.
Homologation is followed by the construction of the prototypes. For this purpose, appropriate approval-relevant tests are carried out in cooperation with a test center and the necessary documentation is compiled. Upon successful completion of the tests, the vehicles will have an operating license from the Federal Motor Vehicle Office, which forms the basis for the approval of the vehicles. They can therefore be used in public road traffic and for the planned test phase.
Already during the development of the electric vehicles, the requirements of the tests are being incorporated into the vehicle concepts. These requirements are strongly dependent on the intended vehicle class and cover areas such as electromagnetic compatibility, the brake system test or the electrical safety of the overall system.
The necessary technical content must be determined for the error possibility and influence analysis and be evaluated in the proper context. Furthermore, an analysis of the functional safety of the development product is to be carried out in the necessary granularity. StreetScooter moderates the execution of the analyzes and the preparation of the documentation to present a necessary product liability insurance.
In the overall ACM project, Green City is responsible for the conceptual development of the eMobility system and its testing in Munich within a field trial. The task of Green City is to design models for the operator role as well as to test application scenarios in different areas along with demonstrating usage variations. For the realization of the field test, the infrastructural prerequisites including the integration of renewable energies are established.
With its many years of experience in the area of consulting and event implementation, Green City is also responsible for the local and transregional networking and anchoring of the project, as well as for publicly effective communication with citizens, energy suppliers and politicians.