Headlight simulator

Objectives

Usually, the development of a new car projector requires the manufacturing of several physical prototypes. These prototypes are assessed through night tests and then modified according to the assessment of lighting experts.

Several long and costly prototype production iterations are necessary before obtaining a projector compliant with the specifications.

The aim of the headlight simulator is to reduce development costs and delays for new projectors, while enhancing its quality, thanks to computer assisted engineering techniques and real time immersive display.

Concept

The Technical Centre for Simulation from Renault has developed a headlight simulation software able to render a high precision visual aspect of a light beam on the road in real-time, thanks to computer generated images.

This software, integrated in SCANeR©kII (a compre-hensive driving simulation software, also developed by the Technical Centre for Simulation), accepts photometrical and color data characterising the projector.

These data are resulting from measurements taken on existing projectors or from computations based on CAD projector models. Thus, a projector can be assessed even before having any physical prototype.

The driver is seated at the simulator driving station. He drives through a virtual environment (e.g. the reproduction of an actual test track or virtual test track synthesizing interesting road stretches). Using the vehicle commands, he/she can switch from low to high beam or fog lights. He/she can also modify in real-time the projector type or version.

A graphical user interface allows to modify in real-time projector parameters such as position, pitch or color. Photometrical measurements can be taken on any point of the road. A grid is displayed on the road for this purpose. Finally, a top view of the track can be displayed, for a better comparison of projector characteristics.

Validation

The simulator has undergone qualitative and quantitative validation carried out by lighting experts from Renault and Valeo (one of Renault’s projector suppliers).

The headlight simulator is in use since 1998 in all of Renault’s vehicle projects. Its benefits include costs savings related to reduction of prototypes for each project.

Blooming simulation

The blooming simulation consists in modeling the behavior of driver’s eye when meeting vehicles (phenomenon of haloes and visual adaptation). It allows to widen the study of the vehicle headlights and to improve the visual and behavior realism of the driver in driving simulation.

Intelligent lighting

Intelligent lighting simulation allows to show beams of light which adapt to driving situation. For example, it allows to adjust the distribution of light according to the steering, to the speed of the vehicle.

This performance offers to the driver a better visibility and a safety increased during night driving.

Technical sheet

The headlight simulator allowed a significant reduction of development time. An improved projector quality is made possible thanks to total control of the test environment. Working conditions of lighting experts are obviously also enhanced.

Fog simulation

To simulate meteorological conditions is an essential point in the design of projectors and the visual ergonomics.

The headlight simulator offers the possibility to simulate in real time the presence of fog and such, of studying the light retro diffused projectors by the droplets of water in suspension. This solution allows to anticipate conception defects often discovered too late in the cycle of development.

  • Visual : Linux and Windows PC, NVidia Graphics Boards
  • Graphical API : Performer, OpenGL, Qt (IHM)
  • Refresh rate : 60 Hz (mono) and 30 Hz (stereo)
  • Horizontal field of view : 210°
 

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