Research in positive psychology indicates that sustained well-being is more determined by our actions than by our possessions. Products' contribution to well-being may thus be grounded in their potential to support well-being-enhancing activities rather than in their material value. In a laddering study, we investigated how products shape a range of well-being determinants, including activities, and well-being outcomes. Following a hierarchical structure, seven product experience qualities, six motivations, and seven activities were empirically found to be linked to long-term well-being. We describe these ingredients for sustained well-being in further detail and provide actionable guidance on how to address them by means of design. As the majority of product-supported long-term well-being outcomes were mediated by activities, we propose activities as most promising starting point in design for sustained well-being.

The emergence of smart materials has urged design education to keep up and take part in introducing them to design students. There has been a great deal of work on teaching conventional materials like wood, metal and polymers in product design. Yet when it comes to learning smart materials, the sources are very limited. Our research group in Delft University of Technology has initiated a number of projects, particularly focusing on understanding technical and experiential characteristics of smart materials as materials of design. Our mission is to communicate smart material qualities through pre-design tinkering activities and functional demonstrators, which also serve as a source for inspiration. In this paper, we explain our approach through an example case on electroluminescent materials.

Control errors often occur in repetitive and monotonous tasks, such as manual assembly tasks. Much research has been done in the area of human error identification; however, most existing systems focus solely on the prediction of errors, not on increasing worker accuracy. The current study examines force responses before, during and after errors in a simulated assembly line task in order to determine an optimal feedback system for error reduction. Confirming previous findings, enhanced movement speed and reduced force occurred before erroneous trials and slowing occurred after erroneous trials. Given the results, we suggest a haptic feedback system which stimulates users to exert increased force levels after completing an erroneous task in order to increase degree of control and re-build worker confidence and thereby reduce overall error rate.

Sometimes, the way in which we interact with products implicitly communicates how we feel. Based on previous studies on how emotions can be detected and communicated via product interaction, we discuss how an interactive product could influence affect by responding and changing behaviors expressing affect. We discuss the proposal of the affective feedback loop in product interaction by its implementation in the prototype of a pen that senses two implicit behaviors related to restlessness, rock and roll. Furthermore, the pen provides inherent feedback, focusing on the perceptual motor skills, as a means to reflect on these behaviors. The pen was evaluated in an experiment, by which we explored whether this type of feedback would influence the emotional experience. Two participant groups were compared, and participants that used the pen with feedback showed a lower heart rate throughout the whole experiment. Because these participants were not aware that the pen provided any feedback, we propose the concept of unaware interaction and discuss what its implications are for design.