Stop and Care — Changing Behaviours Through Participatory Interaction

Stop and Care is part of a project that aims to raise awareness for the urgent matter of water pollution and to change its audience behaviour towards it. The Stop and Care output is a visual composition that represents solid waste floating on water and the amount of pollution in it will depend on its audience. The audience has an active role as the visual environment adapts to their behaviour, representing the impact of the individual care on this subject. By creating a relation between artifact and audience through participatory interaction, we aim to build an experience that goes beyond the moment of the interaction with the artifact and extends to the change of habits of each participant in the future.



Models that address the use of the body and the physical involvement of an audience to promote social changes goes way before the computer age. Many argue in theory the inclusion of the audience to strengthen the relationship of the viewer with what they are observing — instead of the mere passive interpretation [1]. Josephine Bosma argues that it’s in the moment of the participation that the artwork gains meaning [2].

When a visual communication system adapts its characteristics to its context and especially to the behavior of its audience, it creates more customized, meaningful and engaging experiences, enhancing the reception, impact and memorization of the visual message. This approach is particularly relevant to address the audience of the digital society.

Environmental issues are becoming our daily concerns. All types of media are valuable to spread such an urgent message and visual communication is one of the most effective ones. People relate more to a subject if they have an active role in the discussion, so we should include them when communicating this message visually. Considering this challenge, we address this subject using participatory interaction.

In this project we focus on the problematic of water pollution caused by solid waste. Beginning with the sentence “Stop and Care” we created an artifact that grabs the attention of one viewer at a time. By reacting to his/her behaviour, it aims to make him/her aware of the water pollution problem, the impact of individual concern and the need to care, act and change habits. The message is simple: caring — for the planet, for future generations, for our quality of life — is the first step to act. So we start with that.



Using computer vision to detect the existence of a participant and his/her position, we can understand his/her interest towards the subject matter. This dialogue between the artifact and its audience aims to create a closer relation between them which will have a positive impact on how the audience perceives and retains the visual message. What the participant does leaves a personal mark on the visual environment, so the participant can choose to be part of the problem or part of the solution.

The visual environment is composed of rectangular geometric fragments — representing solid waste. To reinforce the crucial role of the viewer in the artifact, he/she is visually represented by the word “YOU”. At this point, the role of the viewer changes from passive spectator to active participant. That element follows the participant’s position and movements creating a straight connection between the participant and the visual environment.

The fragments around the “YOU” element will react to the interest shown by the participant. If he/she gets closer, the fragments around get smaller, on the other hand the fragments get increasingly bigger as he/she gets farther. This way, by showing interest, the participant creates a cleaner environment around him/her (Fig. 1) however, by showing disinterest, he/she creates a more polluted environment (Fig. 2).


Participant closer
Figure 1

A clearer environment is created and the sentences have more detailed content — e.g., avoid disposable plastics — when the participant shows interest.


Participant farther
Figure 2

The environment gets more polluted and the sentences more striking — e.g., it won’t stop until you stop — as the participant gets farther from the artifact.

When the participant stops looking definitely at the screen after being there for only a few seconds, the “YOU” element turns black — the color of waste in our representation — and becomes one more fragment of waste in the environment (Fig. 3). This behaviour is intended to represent the consequences of generalized disinterest on this matter, which is an obstacle to solving the problem.


Participant leaving
Figure 3

The disinterest of the participant leaves a negative mark on the visual environment.

The participant leaves a personal mark on the visual environment that will depend on his/her behaviour and add meaning to the sum of the previous participations. At any time we can observe if there has been a general interest or not from the participants by analyzing the amount of waste left by the ones that did not stopped and cared.

There is also a typographic component that complements the interactive one. While the participant is interacting, some sentences appear over the waste and their content also changes according to the interest shown by the participant. They can be more informative and detailed if the participant is showing interest or they can be more striking and urgent if he/she is disregarding the message.

The next steps will evolve the concept further, increasing the effectiveness and the involvement of the participant in the message. Also the adaptive capacity of the system to its surroundings and to the public behaviour will be further developed and refined.




[1] Claire Bishop. 2006. Participation.

[2] Josephine Bosma. 2006. Art as experience: Meet the active audience. Network art: Practices and positions (2006).




  • B. Sousa, N. Coelho, and P. Machado, “Stop and Care: Changing Behaviours Through Participatory Interaction,” in ARTECH 2019: 9th International Conference on Digital and Interactive Arts, Braga, Portugal, October 23-25, 2019, 2019, p. 79:1–79:4.


Bruna Sousa

Penousal Machado

Nuno Coelho