Last year, at CES 2017, Toyota revealed its Concept-I vehicle, which features an AI assistant – named Yui – which uses light and sound to communicate with the driver. For example, colored lighting illuminates the footwell to indicate whether the vehicle is in manual or self-driving mode. The exterior of the car also uses light to communicate with driver and surroundings. Other automakers are following suit, and turning their attention to the development of interior lighting concepts as a means of brand differentiation. With increasing pressure on automakers to deliver fuel-efficient, low-emission engines, speed and performance is becoming less of a differentiator, so many see ambient lighting as the next battleground.