The article appeared in A&B 4'2021
In the last century, it was proven that sight is the dominant sense of humans. Despite the identical structure of the eyeball, each of us perceives space differently. It depends on one's experience, profession, age or reason for being in a particular place.
An architect will view a city in a specific way, pay attention to solutions or forms invisible to other users of a given space. It is important to understand and be aware of the impact of architects' activities on human comfort and health. Thanks to the development and miniaturization of biometric devices to measure human functioning available in smartwatches, for example, it is possible to monitor human health. An innovative technology that can help architects and designers understand the impact of their design decisions on users is eye-tracking, a method of measuring gaze focus.
what is eye-tracking?
Many of today's technologies that we consider cutting-edge, such as 3D printing, 3D scanning and virtual reality, were actually developed thirty or forty years ago. Thanks to advancing miniaturization, lower production costs or due to the expiration of patents, many technologies previously only available in research units have become available to companies and consumers. Similarly, eye-tracking technology, previously used in scientific research and marketing, is now widely available, allowing it to be applied in areas previously unexplored.
Eye-tracking technology, known as "oculography" in Polish, involves tracking the movement of the user's eyeball. Thanks to it, it is possible to observe and record gaze focus points and patterns of eye movement, professionally referred to as fixations and saccades. By conducting a test on a group of people, we can see what effect the sighted image has on the user. The technology has been rapidly deployed in marketing research for advertising design, graphic identity, storefront design or websites. Marketing teams have the opportunity to compare the visual response of prospective users, choosing solutions that most strongly affect their visual perception.
It is worth briefly explaining how eye movement tracking is possible, even at a frequency of two thousand measurements per second. There are many methods for recording eye movement: from simple observation, mechanical, to advanced ones that study the difference in electrical potentials of the two sides of the eyeball. The most popular method, which ensures high quality measurement and is non-invasive for the user, involves video recording of the eyeball with a special camera. Thanks to the use of an infrared camera that records the movement of the eyeball and a program that interprets successive images of the eye, it is possible to precisely and safely monitor the focus of the eye. Let's focus on the variants used in the field of architecture and urban research.
conducting an eye-tracking study
The most popular method uses a bar located under or above the monitor with a set of cameras, which, after calibration, allows recording the user's gaze. It is possible to present photos or illustrations, for example, visualizations of the planned investment, as well as animations or videos, which are more complicated to analyze, but allow to reflect the specifics of space use. Another method, which gives more freedom to observe the space, is to use a combination of eye-tracking technology and virtual reality. Special goggles equipped with eye-tracking cameras allow the subject to decide for himself which objects he wants to view by turning his head in a virtual object. In addition, by introducing movement in the virtual space, we can achieve conditions close to real life.
The modern development of visualizations, which are already calculated in real time, leads us to believe that it is the combination of VR technology and eye-tracking that will be one of the new tools in the hands of architects and developers. The aforementioned eye-tracking methods make it possible to simulate the designed space or record visual perception based on photos and videos. However, human perception in the actual built environment is much more complicated. Stimuli such as traffic, sound, light or other users of the space also affect the way people observe their surroundings. That's why it's worth mentioning yet another method of eye-tracking that allows for real-world vision registration. Thanks to the miniaturization of technology, special glasses equipped with a set of cameras that record both our eyeballs and the image in front of us are available. Mobile eye-tracking devices make it possible to study the visual reactions of users of office, store or city spaces from the perspective of diverse audiences: children, customers, residents or the elderly, allowing the architect or researcher to understand the behavior of people with different profiles.
eye-tracking in practice
So far used in scientific research, eye-tracking, thanks to its increased accessibility, can be used in research conducted by companies or architectural offices. One example of the use of eye-tracking in urban structure research is to determine the impact of large-format advertising on human perception. Studios that design billboards, signs or posters create content that is meant to catch the eye with its form, content or colors. Designed in isolation from the context in which they are supposed to function, when placed in a public space they shape it, often shattering the architectural order. In response to the worsening problem of the destruction of urban space by large-format advertising, more cities are adopting a landscape resolution, regulating the rules and conditions for the placement of advertising media.
A 2020 study proved the impact of advertising on visual perception. In cities such as Warsaw, Gdansk, Poznan, Wroclaw and Bialystok, the spaces of the centers in their current form devoid of advertising were compared with the same spaces, but supplemented with advertising carriers. Only in the case of Warsaw, where the Landscape Act has not been enacted, were current photos of the center used, along with photos devoid of advertising. The result of the survey of thirty people was an average visual focus on advertising areas of up to forty percent of the time, despite the insignificant size of the space occupied. The form, size and content of advertisements, designed to attract our attention, boggles visual perception, as a result causes increased stress levels, distracts us from our immediate surroundings, negatively affecting our safety.
illustration of eye focus of study participants depicting visual dominance of advertising spaces
eye-tracking in architectural design
Eye-tracking is a technology that can find application in the architectural design process. Designers are familiar with certain formal procedures and often propose solutions that are difficult for investors to accept. Knowing how non-professional observers perceive a space or a given facade composition can give architects additional arguments when talking to clients.
In addition to the oculographic survey conducted on the basis of static images, it is possible to conduct tests of existing urban fabric, ensembles of new residential development or office centers to obtain information on how space is read, or discovered. In conjunction with surveys or EEG studies, such data is invaluable to architects and investors alike, making it possible, for example, to assess how particular material combinations are perceived by users, or where their gaze is focused in a given compositional arrangement in order to place an interesting detail or noble material there.
A study of the public spaces of Polish cities in the context of large-scale advertising has shown that billboards and façade ads impoverish our perception of urban space, focusing most of the attention on themselves. In the same way, designers can be armed to have full control over how their design is perceived by users.