Simulator facilities
The same software is used throughout VTI's simulator environment, making it possible to move experiments between the different simulators. Experiments can also be moved easily to external facilities where the institute's software is used. VTI's software has been implemented and is used in driving simulators at universities and by vehicle manufacturers.
Sim IV
Sim IV has an advanced motion system and is the only one of VTI's simulators to permit significant linear movement along both x and y axes. It is the first choice when simultaneous longitudinal and lateral acceleration is important or if a wide field of vision is prioritised.
Cabs and passenger compartments can be exchanged quickly in Sim IV. The simulator has both a passenger car compartment and a truck cab. It has three LCD displays for rear-view mirrors and a visual system comprising nine projectors.
The visual system gives the driver a 210-degree forward field of vision. The simulator's imaging system has a camera-based calibration system, making it easy to switch between different driver positions.
Sim III
Sim III's linear motion system has world-leading performance. The system allows motion in four degrees of freedom and offers both linear and tilt motion. By linking the cradle's motion to the vehicle's lateral position, the simulator's motion algorithm creates realistic lateral motions. Sim III also has a platform that can be swiveled 90 degrees. This means that the motion system can be used for acceleration and braking instead of lateral forces.
The simulator's visual system consists of three DLP projectors with 4K resolution each. This gives the driver a field of vision of 115 degrees. Three LCD displays are used to simulate rear-view mirrors. Either a passenger car compartment, a truck cab, or a patient-care compartment can be fitted. Sim III has a vibration table that provides high-frequency reproduction of road unevenness and moves the compartment/cab relative to the projected image. Sim III is therefore suitable among other things in experiments with rumble strips.
Minisimulators
VTI even has a number of smaller simulators available. Since 2023, VTI has implemented a new visualization software, which builds on the game engine Unreal Engine 5. It enables to simulate a wide range of environmental conditions, like fog, clouds, rain, snow, dusk and nighttime conditions. Lighting from natural and man-made sources can be simulated.
Minisimulators can be used both with TV screens and XR headsets. Using green screen technology, the virtual environment is combined with the driver’s own hands and the real steering wheel.
Technical specifications
Sim IV | Sim III | |
|---|---|---|
Motion system | ||
Pitch (degrees) | ± 16,5 | -9 to +14 |
Roll (degrees) | ± 16,5 | ± 24 |
Linear system | ||
Amplitude (m) | ± 2,5 / ± 0,31 (surge) | ± 3,75 |
Velocity (m/s) | ± 2,0 / ± 0,8 (surge) | ± 3,75 |
Acceleration (m/s²) | ± 5,0 / ± 6,5 | ± 8,0 |
Vibration table | (N/A) | |
Vertical motion (cm) | — | ± 6,0 |
Longitudinal motion (cm) | — | ± 6,0 |
Roll (degrees) | — | ± 6 |
Pitch (degrees) | — | ± 3 |
Visual system | ||
Forward view (degrees) | > 180 | 115 |
Rear view mirrors (LCD screens) | 3 | 3 |
Average resolution on screen* | 1,8** | 1,7 |
Cabin (exchangeable) | Volvo XC60 or Volvo FH | Saab 9-3, Scania CP14 or patient-care compartment |
*The human eye has 0.59 arc minute per line pair
** ± 0,5
Rail simulator
The same technique as in VTI:s driving simulators can be applied in the rail area. VTI has developed a rail simulator that can simulate a train driver's work environment. The simulator can be built as a complex solution with a cabin as well as desktop or lap-top installations, depending on the planned usage.
Visual system
The visual system consist of three 40 inch NEC M40-AV TFT with 1 920 x 1 200 pixel resolution, providing a 180º FOV. The resolution can be set to smaller sizes to adapt to different graphic card capacity.
Moving base system
The motion platform is a 2 dof system which provide tilting motion laterally and longitudinally. Maximal tilting angle is ±6º, which corresponds to a sideways lifting of ±11 cm. Force feedback and vibrations on the steering wheel are present.
Simulation software
The Foerst simulator runs both VTI's simulator software and simulator software provided by the supplier (Foerst GmbH) that is dedicated to driver training. The software provided by the company focuses on driver training, but has as well different modules for eco-driving and driver assistant systems. Additional software modules are developed and tested by ongoing projects.
Sound system
Logitech Z-5500 5.1 system. 4x62 W+188 W sub.
Configuration: 2 front channels for high frequencies, 2 rear channels for low frequencies, and subwoofer.
Computer system and software
The simulator runs on a single Win XP PC, software control of the motion platform is via dedicated drivers for the motion controller card, connected via a single USB cable.