12 ESP-LWXT-0.6 projectors with WUXGA resolution enable an impressive driving experience. A 241° front projection with approx. 10800x1920 pixels is achieved using 9 projectors. 3 further projectors display the appropriate rearview mirror perspectives on the dome wall. Aided by the openWARP2 System from eyevis, the geometrical corrections required for the curved dome wall are calculated in real-time, within a single frame. Parameterization of the warp matrices is performed using the camera-based auto-calibration system developed by domeprojection.com. The images are rendered by powerful graphics computers with i7-6850K processors and Geforce GTX 1080 TI graphic cards.
The motion system of the Stuttgart driving simulator consists of a sled system for simulating large, linear accelerations in the vehicle's longitudinal and lateral directions, plus a hexapod installed on top. Altogether, the system has 8 degrees of freedom and can implement linear movements in a working area of 10 m x 7 m. This means lane-changing and transient operations during starting or gear-changing can be represented without the need for scaling. It is also able to reproduce combined longitudinal and lateral movements which occur both in normal driving and automated driving. It can reproduce accelerations of up to 8 m/s^2 as well as rolling, pitching and yawing movements.
Simulation of vibrations
Using the hexapod, oscillators on the vehicle chassis and a system of loudspeakers, it is possible to cover the entire frequency range of the vibrations occurring in vehicles. This achieves a realistic representation of the ambient noises and vehicle vibrations, as well as focused influencing of tactile and aurally-perceptible vibrations due to road/tire, engine or chassis excitation.
A variety of loudspeakers are mounted within the dome to reproduce the driving noise conditions. The four loudspeakers positioned on the lower dome wall aid the positioning and representation of surrounding noises, such as passing vehicles. These are also used to generate wind noise and tire rolling noise. The drivetrain noises are simulated by two loudspeakers within the mockup. Two further Bluetooth loudspeakers permit additional noise sources to be positioned at different locations. Digital formats such as MADI and AES3 are used to connect the loudspeakers.
Sensor test bench
Appropriate connections are provided on a separate test bench to incorporate/test (partly) intelligent sensors. Here GPS signals can be provided via a GPS simulation from Spirent, as well as the electronic horizon in ADASIS format. Furthermore, the camera systems can be supplied with appropriate artificial images. Access to the vehicle data is also ensured via a CAN bus. Other communication media such as Ethernet, USB etc. can also be used. A variety of development platforms (VRmagic D3, Nvidia PX2, BP-ECS7800, …) are available for testing new sensor applications.
Connection to other test facilities
The vehicle simulator system is able to communicate with a drivetrain test bench via a real-time-capable data connection. With this combination of "driver-in-the-loop" and "hardware-in-the-loop", the drivetrain receives the driving resistances from the environmental simulation and the driver inputs, such as accelerator position, as inputs. In return, the driver receives direct feedback about the drivetrain behavior. In this way, both sides can profit from an increase in the depth of reality.
UDP connections are established to link the different simulation systems. TCP communication enables the configuration of the systems and changing of the parameters during runtime. From December 2017, the integrated Reflective Memory network will, to a great extent, replace the existing UDP communication and enable a rapid, synchronized exchange of data. The configuration data is backed up using an SQL server, permitting repeatability and transferability of the simulations performed.