# AI-For-Mobility--A New Research Platform for AI-Based Control Methods
## 2 Vehicle Architecture
### Full By-Wire Control System  
The AFM is equipped with a full drive by-wire (DBW) kit. It enables control of the steering wheel angle or steering wheel torque (control of lateral dynamics), as well as of the throttle and brake pedal position (control of longitudinal dynamics). Furthermore, it is possible to actively select a gear via an extra actuator (shift by-wire) thanks to a modification of the gear selector. Besides the shift by-wire module, the DBW kit only uses the existing actuators of the basic vehicle. A virtual accelerator and brake pedal position is given via an emulator. The existing interface of the adaptive cruise control (ACC) function is utilized for controlling necessary braking and engine operations. To specify a steering wheel angle or steering torque, the interface to the electronic power steering (EPS) system is controlled by an ECU.  
The DBW kit allows for driving reproducible maneuvers. This feature plays a key role for the evaluation of different control algorithms or setups since they can only be meaningfully compared on the basis of identical maneuvers. In addition, the DBW kit replaces the functionalities of a steering robot such that maneuvers like a Sine with Dwell test [18] can be precisely performed.  
The DBW system installed in the AFM provides several advantages compared to other systems where additional actuators have to be installed on the steering column and on the pedals of the basic vehicle in order to set a desired value mechanically. First, it reduces the costs of retrofitting additional actuators. Second, the DBW kit prevents different actuators from interfering with each other (e.g., in the case of an ESC intervention), which can lead to undesirable or even dangerous system behavior.  
The DBW kit enables automated driving of the AFM over the entire operating range, from executing parking maneuvers with forward and reverse switching to high-speed driving. Automated driving is performed exclusively with an operator on board. As a safeguard, the activated DBW kit constantly monitors possible driver inputs. A detected steering wheel torque, brake or accelerator pedal position is interpreted by the system as a take-over request causing it to deactivate and return control to the human driver. As  
Figure 4: AFM experiments on a vertical dynamics test rig.  
an additional safety mechanism, the driver can activate the emergency stop switch in the center console in case of an emergency, which disconnects the power supply to all auxiliary components and consequently the DBW kit (cf. Section 2.5).  
The AFM with its DBW kit was inspected by an independent technical testing authority. As a result, it received a special approval for public road use based on the review of circuit diagrams and safety mechanisms integrated by the system's manufacturing company. The AFM is allowed to be operated on public roads when the system is enabled without any active intervention in the vehicle control. In this case, the subsystems of the DBW kit only collect data. As soon as the DBW system has been activated to influence the vehicle guidance, the AFM is allowed to be used only in test areas.  
The DBW kit is connected via a CAN bus to the Rapid Control Prototyping (RCP) platform, on which all control algorithms are computed (see Section 2.3.1) and from where the command values are sent to the DBW system.