25 years of Renault Group driving simulators: on the road towards full immersion
Before the first digital simulators saw the light of day, Renault Group's prototypes were only put through physical tests (on road or testing lines) to assess performance and equipment. A costly exercise, especially when it was to put the latest technology, such as ADAS, through its paces.
Since digital tool took over by storm, digital simulation (used in particular for driving simulation) has changed the game. Faster, cheaper, fewer prototypes – the cost of vehicle design and development has been reduced dramatically.
From 1998 to 2023, from HELIOS to ROADS: five generations of ground-breaking simulators that saw Renault Group lead digital innovation.
1998: HELIOS lights the road ahead for simulators
In the late 1990s, lighting of vehicles was developed and validated on a simulator. Before then, multiple physical prototypes were required for any new lighting system. Launched in 1998 under the name of HELIOS (Headlight Operating System), this simulator helped reduce the number of physical prototypes needed to design new headlights, while also helping to improve their performance: range, colour consistency, and level of glare. Not to mention night tests for headlights, now possible during the day.
To keep up with the pace of evolving technology, HELIOS has been updated on multiple occasions during its time. Since its last update in 2017, HELIOS can now recreate the way lights illuminate the road in an ultra-realistic way: eight ultra-high definition 4K projectors (pixels are no longer visible to the naked eye), high contrast for optimized visualization at night, all on a 225° spherical screen that fills the driver’s field of view entirely.
Mounted atop moving electronic pistons, HELIOS can imitate basic vibrations. HELIOS was recently used to validate the Matrix LED Vision technology used on Austral, All-new Espace and All-new Rafale.
2001: C-CARDS, the first dynamic simulator of Renault Group
Renault Group’s first dynamic driving simulator, C-CARDS (Comprehensive Automobile Research and Development Simulator) was developed as part of a Europe-wide project and launched in 2001. The front image was projected on a 150° horizontal display and its system of movements accelerates up to 0.5G. Successive versions of C-CARDS have notably improved its projection system with a screen now measuring 270°, which is the same as a driver’s full field of view. C-CARDS is used to evaluate new concepts relating to ergonomics, human-machine interface (HMI), and, more recently, ADAS functioning. C-CARDS is particularly suitable when using the rear screen to study the impact of blind spots on traffic insertion.
The EHS simulator (Ergonomics and HMI Simulator) was commissioned in 2013 to extend the system’s capacity to assess ergonomics and HMI. Complementary to C-CARDS, the EHS is a static driving simulator (no acceleration feedback for the driver) comprising a modular cockpit that includes a modular dashboard display with multimedia systems, placed in front of three 4K screens that display the drive.
2004: ULTIMATE, the high-performance dynamic simulator
When it was launched in 2004, this stimulator was the first of its kind for a car manufacturer. Its unique architecture featured a full driver set-up and panoramic display. The system is completed by a hexapod system of pistons and a cross-working table. The hexapod system reproduces a car’s movements in all directions (pitch, roll, and yaw). The cross-working table, also known as an X-Y table, provides simultaneous lateral and longitudinal movements over a 5m by 5m span and accelerates up to 0.7G.
ULTIMATE’s range of motion realistically recreates physical sensations felt when accelerating.
Before ROADS, ULTIMATE was the Group's largest dynamic simulator. Since the beginning, it has served a range of purposes, like simulating accident-prone situations by accurately measuring driver reactions. Simulation is made to appear realistic through the use of a variety of driving situations scenarios and traffic generation for the test. It has been used of late for tests on electric vehicles, such as regenerative braking to improve battery range, and the vehicle’s sound design.
2013: CAVE, a step towards visual realism
A CAVE (Cave Automatic Visualization Environment) is an immersive room whose walls, floor and ceiling are in fact for life-sized 3D displays. It goes hand in hand with virtual reality headsets that are also used by Renault Group. The CAVE originally installed in 2014 is called IRIS (Immersive Room and Interactive System). The 3D immersion can be used to observe and interact with a fully virtual vehicle, the “virtual twin” of the future car. The user wearing the VR glasses is placed inside or outside a virtual car, while the 1:1 scale image follows their head's movements. Images are refreshed in real time for a fully immersive experience. IRIS can be used to validate the vehicle’s architecture (field of view through the windshield, etc.), or the perceived quality of the car’s interior and exterior.
This type of system has also been deployed at the Engineering Centre in Romania (RTR), for Dacia.
2023: ROADS, makes its grand entry as the world’s most powerful simulator
One of a kind, ROADS (Renault Operational Advanced Driving Simulator) is the most powerful simulator in the world. Unveiled in 2023, it is housed in the 2,300m2 ROADS building.
The simulator boasts impressive features: up to 1G of lateral and longitudinal acceleration on 25m-by-25m rails (about 10 times the area of ULTIMATE), moving speeds up to 9m/s, response time less than 30 milliseconds (compared to 250ms for ULTIMATE), a projection system inside the dome using 15 2.5K video projectors that generate both 2D and 3D 360° high-definition images.
For an added futuristic touch, entry into the dome is achieved via a closed walkway situated 4 meters above the ground. Test drivers make their way inside the simulator without ever seeing the mechanism behind the scenes, thereby guaranteeing a more immersive experience, and giving the feeling of being in a real driving situation. The vehicle cockpit placed in the dome can be changed to ensure the physical space is as similar as possible to the digital vehicle being tested.
Unlike early generation simulators, ROADS can be used to also test ADAS technology in risky driving conditions (emergency braking, trajectory control systems...) and road handling of future vehicles. Ultimately, ROADS means testing of future models in the line-up takes on a whole new dimension: more precise, faster, and above all, more immersive.
