Evidence for Human-Centric In-Vehicle Lighting: Part 1

Abstract

Today, up to hundreds of RGB and W-LEDs are positioned in a vehicle’s interior context and are able to be individually controlled in intensity, color and sequence. However, which kind of illumination distracts or supports car occupants and how to define such a modern illumination system is still under discussion and unknown. For that, first a definition for an in-vehicle lighting system is introduced. Second, a globally distributed study was performed based on a free-access online survey to investigate in-vehicle lighting for visual signaling within 10 colors, eight positions and six dynamic patterns. In total, 238 participants from China and Europe rated color preferences, color moods, light-position preferences, differences between manual and autonomous driving and also different meanings for dynamic lighting patterns. Out of these, three strong significant (p < 0.05) color preference groups were identified with a polarized, accepted or merged character. For the important driving-signaling mood attention, we found a significant hue dependency for Europeans which was missing within the Chinese participants. In addition, we identified that light positioned at the door and foot area was globally favored. Furthermore, we evaluated qualitative results: men are primarily focusing on fast-forward, whereas women paid more attention on practical light usage. These findings conclude the need for a higher lighting-car-occupant adaptation in the future grounded by deeper in-vehicle human factors research to achieve a higher satisfaction level. In interdisciplinary terms, our findings might also be helpful for interior building or general modern cockpit designs for trains or airplanes.

Evidence for human-centric in-vehicle lighting: Part 2—Modeling illumination based on color-opponents

“…Compared to our first online survey (Weirich et al, 2022) the average participating time increased by around 4 min. With around 23 min on average, the survey can be classified as comprehensive and close to the reasonable limit, which was also shown in expressions as "too-much."…”

“…We were able to collect 164 full completed answers with 120 male and 44 female participants, primarily operating the survey using the Chinese language and located in China. Out of the first question part, we collected an age class difference of 1.56, meaning that the European group was on average more than 10 years older than the group of China, similar to in our first part (Weirich et al, 2022 ). Also, with the background of the global demographic change of our society, we kept this separation by knowing that its statistical power will be lower compared to the Chinese group based on the smaller sample size.…”

“…First, a short study-introduction movie was presented. Second, basic subject information was collected, which was similar to our first part (Weirich et al, 2022) (1)…”

“…In part one of our mini-series about human-centric in-vehicle lighting (Weirich et al, 2022 ), we investigated the application of ambient light in an indoor signaling context globally. We schematically designed luminaires in line shapes, positioned at state-of-the-art vehicle positions, and vary them by 10 different mono- and multichromatic colors to create specific visual stimuli for ambiance and messaging.…”

Evaluation of a User-adaptive Light-based Interior Concept for Supporting Mobile Office Work during Highly Automated Driving

“…Such adaptations could be based on monitoring the user's current activity and interpreting their associated perceived needs. For instance, to support users and increase comfort, such systems could adapt the interior light setup (Weirich, Lin & Khanh 2022), or suggest routing changes for longer automated drives (Ihme et al 2021) depending on activity and state of the users. The question remains how to best realize adaptions of the vehicle and communicate these to the user.…”