Benefits of bringing the real world to the lab: investigating lighting behaviour in homes using a full-scale model
(2018) CIE Expert Tutorial and Workshop on Research Methods for Human Factors in Lighting p.40-41- Abstract
- 1. Motivation, specific objective
To evaluate the first prototype of a home lighting system, we used a full-scale model of a studio apartment in the laboratory of the School of Architecture at Lund University. The personalised home lighting system is based on LEDs, wearable sensors and a mobile phone app to produce lighting tailored to the individual’s needs. Drawing on participant interviews (n = 28), which were held in the full-scale model, this paper seeks to highlight the benefits of using a three-dimensional representation at full-scale.
Studying real-world problems that involve people’s behaviour do not always allow research in their natural environment. Investigators must therefore choose other methods. One option is to... (More) - 1. Motivation, specific objective
To evaluate the first prototype of a home lighting system, we used a full-scale model of a studio apartment in the laboratory of the School of Architecture at Lund University. The personalised home lighting system is based on LEDs, wearable sensors and a mobile phone app to produce lighting tailored to the individual’s needs. Drawing on participant interviews (n = 28), which were held in the full-scale model, this paper seeks to highlight the benefits of using a three-dimensional representation at full-scale.
Studying real-world problems that involve people’s behaviour do not always allow research in their natural environment. Investigators must therefore choose other methods. One option is to use a two-dimensional visual representation of the real-world environment, e.g. photography prints or static or dynamic visual simulations on a flat screen. A second option is a 3D-simulation with special glasses. A third is to create the desired environment using either small-scale or full-scale models. Each approach has merits and limitations but, in lighting research, the effects produced by lighting, such as visual comfort, must be considered. The lighting situation is always influenced by the light source and the luminaire, the surfaces of the space reflecting the light, and the observer perceiving the light (individual characteristics and previous experiences). Neuroimaging studies have found that sensorimotor systems are engaged when humans experience the environment around them, and when viewing images or other people. Both mind and body can be activated, e.g. emotions and facial expressions. However, images have several limitations. Firstly, images projected on modern screens cannot produce glare, which makes evaluating simulated lighting situations difficult. Secondly, flat images cannot capture well enough how lighting is influenced by spatial and surface characteristics. Thirdly, 2D-simulations or photographs on a flat screen do not enable a full mind-body experience since physical movement within the space is not possible.
2. Methods
Both quantitative and qualitative data were collected during April and May 2016 using a convenience sample (n = 28, 50% female, median 41 yr). Each participant was engaged for a 24-hour trial in the field and for one hour in the lab. On the first day, the participant received the wearable sensors, which measured light exposure and rest and activity patterns. After 24 hours the participant returned to the lab and was given a demonstration of the new home lighting system in a full-scale model of a studio apartment (floor area 38 m2). A small self-service breakfast buffet was included in the ‘kitchen’. The participant completed a questionnaire addressing the comfort of wearing the sensors and the participant’s willingness to use the home lighting system in the future. To cross-check the assessment and to provide supplementary information, the trial ended with a structured interview with open-ended questions, lasting 10-30 minutes. The interview questions addressed lighting behaviour in the participant’s home: which lights were turned on in the morning and evening (including digital screens), the use of daylight and shades, and the darkening of the bedroom at night. The interview involved the participant giving a detailed description of the home environment. The interviews were analysed thematically to provide a deeper understanding of factors influencing their willingness to use the home lighting system or not. Additional themes were the lighting vocabulary used by participants, the effect of available daylight on participants’ use of electric light, and methodological insights.
3. Results
The results relevant to this paper concern the methodological insights. The physical setting, where the interview took place, enabled participants to describe better their home environment. Eleven participants made comments comparing their own home characteristics and those of the full-scale model in terms of:
•room layout and furnishing,
•size of window openings,
•participant-designed blackout screens in the bedroom,
•thickness, transparency or colour of curtain fabrics,
•type of luminaire: floor-standing or ceiling mounted,
•size of luminaires,
•placement of floor-standing luminaires,
•design of floor-standing luminaires,
•colour tone of lamps (cooler or warmer, bluish or yellowish).
Participants who gave poor descriptions of their home environment were encouraged to compare to the objects and materials in the full-scale setting.
An unexpected benefit of the physical setting was the less formal atmosphere created by the homelike appearance of the full-scale model. It is reasonable to assume that interviews conducted in a homelike environment, seated on a sofa or in an armchair, might make participants more relaxed. Participants were surprisingly open about their everyday behaviours, e.g. sleep habits, clothing or no clothing at night.
4. Discussion and conclusions
As several participants, unrequested, used objects or materials in the full-scale model for comparison when describing features of their own home, it is suggested that a three-dimensional representation at full-scale might elicit more information from the participants. Even though the setting does not fully correspond to a residential environment, there are differences between looking at a place and being in a place. In participants’ appraisal of a place, lack of colours and textures, on the walls and the ceiling, is not necessarily a problem.
Previous research studies used systematic evaluations of 2D- and 3D-simulations, and real settings. A Swedish study investigated participants’ assessment of four different car interiors, both real cars and photographs on a computer screen using the Semantic Environment Description method. Results showed that the evaluation between the real situation and the visual representation differed in terms of ‘unity’, ‘complexity’, and ‘enclosedness’. A more recent Swedish study, exploring the reliability of colour and light appearance in 3D-models, showed that colour variations and shadows in renderings have improved, but contrast effects and inter-reflections between angled surfaces are still incorrectly represented.
To illustrate the limitations of images on a flat screen, watching a movie at the cinema may serve as an example. Movie scenes on a large screen can evoke strong sensations, for example, sudden noises. But have you ever been blinded by, for example, the sun in a science-fiction movie?
(Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/389e146f-0e74-463a-9953-5d6fa3cbe494
- author
- Gerhardsson, Kiran Maini LU
- organization
- publishing date
- 2018
- type
- Contribution to conference
- publication status
- published
- subject
- pages
- 2 pages
- conference name
- CIE Expert Tutorial and Workshop on Research Methods for Human Factors in Lighting
- conference location
- Copenhagen, Denmark
- conference dates
- 2018-08-13 - 2018-08-14
- project
- Rise and Shine! Health benefits as drivers for energy efficient light in Swedish homes
- language
- English
- LU publication?
- yes
- id
- 389e146f-0e74-463a-9953-5d6fa3cbe494
- alternative location
- http://files.cie.co.at/CIE%20Expert%20Workshop%20on%20Research%20Methods%20for%20Human%20Factors%20in%20Lighting%20-%20V2.pdf
- date added to LUP
- 2018-12-04 18:22:33
- date last changed
- 2023-11-14 14:37:26
@misc{389e146f-0e74-463a-9953-5d6fa3cbe494,
abstract = {{1. Motivation, specific objective<br/>To evaluate the first prototype of a home lighting system, we used a full-scale model of a studio apartment in the laboratory of the School of Architecture at Lund University. The personalised home lighting system is based on LEDs, wearable sensors and a mobile phone app to produce lighting tailored to the individual’s needs. Drawing on participant interviews (n = 28), which were held in the full-scale model, this paper seeks to highlight the benefits of using a three-dimensional representation at full-scale.<br/><br/>Studying real-world problems that involve people’s behaviour do not always allow research in their natural environment. Investigators must therefore choose other methods. One option is to use a two-dimensional visual representation of the real-world environment, e.g. photography prints or static or dynamic visual simulations on a flat screen. A second option is a 3D-simulation with special glasses. A third is to create the desired environment using either small-scale or full-scale models. Each approach has merits and limitations but, in lighting research, the effects produced by lighting, such as visual comfort, must be considered. The lighting situation is always influenced by the light source and the luminaire, the surfaces of the space reflecting the light, and the observer perceiving the light (individual characteristics and previous experiences). Neuroimaging studies have found that sensorimotor systems are engaged when humans experience the environment around them, and when viewing images or other people. Both mind and body can be activated, e.g. emotions and facial expressions. However, images have several limitations. Firstly, images projected on modern screens cannot produce glare, which makes evaluating simulated lighting situations difficult. Secondly, flat images cannot capture well enough how lighting is influenced by spatial and surface characteristics. Thirdly, 2D-simulations or photographs on a flat screen do not enable a full mind-body experience since physical movement within the space is not possible.<br/><br/>2. Methods<br/>Both quantitative and qualitative data were collected during April and May 2016 using a convenience sample (n = 28, 50% female, median 41 yr). Each participant was engaged for a 24-hour trial in the field and for one hour in the lab. On the first day, the participant received the wearable sensors, which measured light exposure and rest and activity patterns. After 24 hours the participant returned to the lab and was given a demonstration of the new home lighting system in a full-scale model of a studio apartment (floor area 38 m2). A small self-service breakfast buffet was included in the ‘kitchen’. The participant completed a questionnaire addressing the comfort of wearing the sensors and the participant’s willingness to use the home lighting system in the future. To cross-check the assessment and to provide supplementary information, the trial ended with a structured interview with open-ended questions, lasting 10-30 minutes. The interview questions addressed lighting behaviour in the participant’s home: which lights were turned on in the morning and evening (including digital screens), the use of daylight and shades, and the darkening of the bedroom at night. The interview involved the participant giving a detailed description of the home environment. The interviews were analysed thematically to provide a deeper understanding of factors influencing their willingness to use the home lighting system or not. Additional themes were the lighting vocabulary used by participants, the effect of available daylight on participants’ use of electric light, and methodological insights. <br/><br/>3. Results<br/>The results relevant to this paper concern the methodological insights. The physical setting, where the interview took place, enabled participants to describe better their home environment. Eleven participants made comments comparing their own home characteristics and those of the full-scale model in terms of: <br/>•room layout and furnishing,<br/>•size of window openings, <br/>•participant-designed blackout screens in the bedroom,<br/>•thickness, transparency or colour of curtain fabrics,<br/>•type of luminaire: floor-standing or ceiling mounted,<br/>•size of luminaires,<br/>•placement of floor-standing luminaires,<br/>•design of floor-standing luminaires,<br/>•colour tone of lamps (cooler or warmer, bluish or yellowish).<br/>Participants who gave poor descriptions of their home environment were encouraged to compare to the objects and materials in the full-scale setting. <br/><br/>An unexpected benefit of the physical setting was the less formal atmosphere created by the homelike appearance of the full-scale model. It is reasonable to assume that interviews conducted in a homelike environment, seated on a sofa or in an armchair, might make participants more relaxed. Participants were surprisingly open about their everyday behaviours, e.g. sleep habits, clothing or no clothing at night. <br/><br/>4. Discussion and conclusions<br/>As several participants, unrequested, used objects or materials in the full-scale model for comparison when describing features of their own home, it is suggested that a three-dimensional representation at full-scale might elicit more information from the participants. Even though the setting does not fully correspond to a residential environment, there are differences between looking at a place and being in a place. In participants’ appraisal of a place, lack of colours and textures, on the walls and the ceiling, is not necessarily a problem.<br/><br/>Previous research studies used systematic evaluations of 2D- and 3D-simulations, and real settings. A Swedish study investigated participants’ assessment of four different car interiors, both real cars and photographs on a computer screen using the Semantic Environment Description method. Results showed that the evaluation between the real situation and the visual representation differed in terms of ‘unity’, ‘complexity’, and ‘enclosedness’. A more recent Swedish study, exploring the reliability of colour and light appearance in 3D-models, showed that colour variations and shadows in renderings have improved, but contrast effects and inter-reflections between angled surfaces are still incorrectly represented. <br/><br/>To illustrate the limitations of images on a flat screen, watching a movie at the cinema may serve as an example. Movie scenes on a large screen can evoke strong sensations, for example, sudden noises. But have you ever been blinded by, for example, the sun in a science-fiction movie? <br/>}},
author = {{Gerhardsson, Kiran Maini}},
language = {{eng}},
pages = {{40--41}},
title = {{Benefits of bringing the real world to the lab: investigating lighting behaviour in homes using a full-scale model}},
url = {{http://files.cie.co.at/CIE%20Expert%20Workshop%20on%20Research%20Methods%20for%20Human%20Factors%20in%20Lighting%20-%20V2.pdf}},
year = {{2018}},
}