Investigating the Effect of Operation Mode and Manifestation on Physicalizations of Dynamic Processes

TL;DR

This study investigates how the manifestation (physical vs virtual) and mode of operation (manual vs automatic) of representations influence the communication of dynamic pathophysiological processes. Using a $2\times 2$ full-factorial within-subject design with 28 participants, the authors model cardiac function via a pump metaphor across four scenarios, employing quantitative quizzes, NASA TLX, and engagement measures along with qualitative feedback. Quantitatively, physical manifestation and manual operation elevate engagement and perceived non-visual understanding, but do not yield measurable gains in objective understanding; qualitatively, non-visual and haptic cues enhance perceived learning, suggesting a dissociation between engagement and test-based learning. The work highlights the potential of physicalizations to convey complex dynamics, while underscoring the importance of direct interactivity and haptic feedback for fully realizing their educational impact and guiding future design in medical education tools.

Abstract

We conducted a study to systematically investigate the communication of complex dynamic processes along a two-dimensional design space, where the axes represent a representation's manifestation (physical or virtual) and operation (manual or automatic). We exemplify the design space on a model embodying cardiovascular pathologies, represented by a mechanism where a liquid is pumped into a draining vessel, with complications illustrated through modifications to the model. The results of a mixed-methods lab study with 28 participants show that both physical manifestation and manual operation have a strong positive impact on the audience's engagement. The study does not show a measurable knowledge increase with respect to cardiovascular pathologies using manually operated physical representations. However, subjectively, participants report a better understanding of the process-mainly through non-visual cues like haptics, but also auditory cues. The study also indicates an increased task load when interacting with the process, which, however, seems to play a minor role for the participants. Overall, the study shows a clear potential of physicalization for the communication of complex dynamic processes, which only fully unfold if observers have to chance to interact with the process.

Figures (6)

• Figure 1: Comparison of the physical and virtual representation. The pump (1) on the canister (2) represents the basic heart function. Liquid is transported to the buffer vessel (3) on the right. The level indicator (4) marks the point at which the water level has to be kept to represent 5--6 L/min of flow. The valve (5) leads into the reservoir (6).
• Figure 2: Scenarios, representing different heart conditions with a virtual (top) or physical metaphor (bottom).
• Figure 3: Histogram matrix of TLX scores by manifestation and operation mode. Average scores per participant across dimensions are shown behind the dashed lines. The manualmanual row shows an increased task load.
• Figure 4: Histogram matrix of engagement scores by manifestation and operation mode. Average scores per participant across dimensions are shown behind the dashed lines. Both manualmanual and physicalphysical sides show an increase in engagement.
• Figure 5: Stacked bar charts of preference votes for the different models. All participants chose their most (green) to least preferred (red) representation in the final questionnaire. physicalPhysicalmanualmanual representations are significantly more preferred than others, while virtualvirtualautomaticautomated are the least popular.