Simulation for pre-visualizing and tuning lighting controller behavior

Abstract

We present a computer graphics simulation framework to pre-visualize and tune the parameters of an advanced lighting controller for a given illuminated environment. The objective is to show that the simulation framework makes it easy for a user to predict the controller's behavior and modify it with minimal effort. Our methodology involves off-line pre-computation of lightmaps created from photorealistic rendering of the scene in several basis lighting configurations, and the subsequent combination of these lightmaps in a video game engine. We demonstrate our framework in a series of experiments in a simulation of a conference room currently under physical construction, showing how the controller can be easily modified to explore different lighting behaviors and energy use tradeoffs. The result of each experiment is a computer-generated animation of the lighting in a room over time from a single viewpoint, accompanied by estimated measurements of source input, light sensor output, and energy usage. A secondary objective is to match the simulation as closely as possible to a real physical environment with physical electric light sources and sensors. We demonstrate this calibration in a highly controlled lighting research environment, showing how measurements of source and sensor specifications enable the output of the virtual sensors in the simulation to match the outputs of real sensors in the physical room when applying the same control law in both cases. Our research is aimed at both lighting designers seeking to quantitatively predict real-world controller behavior, and control algorithm researchers seeking to visualize results and explore design tradeoffs in realistic use cases. Furthermore, these simulation tools can aid in the benchmarking of candidate daylighting and lighting control algorithms for a given space.