Direct interaction with cultural heritage (CH) artefacts is frequently unavailable to visitors, offering an opportunity for HCI designers to explore integrating material aspects into digitally-mediated encounters with CH artefacts. We argue that a thorough understanding of the material experiences of CH artefacts can open a novel design space, enabling engaging and meaningful interactions with digital representations. Capitalising on this potential, we present a user study where we systematically explore the material experiences of historic pop-up and movable books. Our analysis identifies five key material qualities to inspire augmentation: fold-ability, slide-ability, tear-ability, age-ability, and print-ability. Highlighting how these material qualities can inspire novel interactions with their digital representations, we present two extended-reality (XR) prototypes of a CH book. With our work, we present HCI designers with a novel approach on designing CH experiences, firmly rooted in materiality, challenging the prevalent paradigms of 'technology-driven' or 'as-realistic-as-possible' sensory experiences often found in CH-HCI.

BACKGROUND: A valid distribution of key anthropometric parameters among participants is often a perquisite of ergonomics research. OBJECTIVE: In this paper, we investigated the accuracy of self-reported stature and body mass of the population in the Netherlands. METHODS: Data from 4 experiments was synthesized where in each experiment, participants self-reported their stature and body mass prior to being measured, of which they were not notified before. RESULTS: Statistical analysis of 249 records indicated that on average, participants overreported their stature by 1.31 cm and underreported their mass by 1.45 kg. This is especially true for people with a BMI ≥ 25. CONCLUSION: Two models were proposed to adjust the self-reported stature and body mass for ergonomic researchers in a survey or recruitment. Limitations in using the models are highlighted as well.

Flavobacteria, which can be found in marine environments, are able to grow in highly organized colonies producing vivid iridescent colorations. While much is known about the biology of these organisms, their design potential as responsive media in user interfaces has not been explored. Our paper aims at bridging this gap by providing insights into the type, degree, and duration of change in Flavobacteria's expression, i.e., their living aesthetics. We present a tool to capture and characterize these changes concerning form, texture and iridescent color. To support the long-term study of their living aesthetics, we designed Flavorium. This bio-digital artifact provides the necessary habitat conditions for Flavobacteria to thrive for a month. Granting insights into the responsive behavior of this organism, this work presents a design space, vocabulary, and application concepts to inspire HCI and design scholars to investigate the complex temporal qualities of living media for future user interfaces.

Acquiring an accurate 3D scan of the human hand is a challenging task, mainly due to the complicated geometry and the instability of the hand. In this paper, we present a low-cost photogrammetry-based scanner that is designed for scanning the human hand. The scanner has fifty modules, each has a Raspberry Pi with an 8-megapixels camera. They are uniformly positioned in two parallel frames and 96% of a hand surface can be viewed by at least 3 cameras. Using the timestamp method, we synchronize the shutters of the 50 cameras within the range of 80 ms to minimize the influence of the instability of the hand. Moreover, the scanner is easy to build with its modular design, and easy to operate with a laptop that is connected to the system by WiFi. Using a 3D printed prosthetic hand, we compared the 3D scanning accuracy of the proposed scanner with the Artec Spider® scanner. The mean absolute error between the two scans is 0.62 ± 0.28 mm. It is concluded that the proposed hand scanner can be used as a low-cost yet accurate tool in many applications, such as personalized product design.

Various imaging techniques are used to visualise issues regarding a painting’s appearance before, during and after conservation treatments, i.e. visible light photography (VIS) raking light photography (RAK), ultraviolet fluorescence photography (UVF) and reflectance transformation imaging (RTI). However, these techniques cannot always visualise and/or quantify conservation issues. This paper presents a new approach: colour, gloss, topography imaging (CGT). CGT’s applicability as a non-invasive tool for evaluating and documenting conservation treatments in comparison to VIS, UVF, RAK and RTI is discussed. Applying this to case studies with different conservation dilemmas illustrates the technique’s potential and drawbacks. CGT can visualise issues such as gloss variations, resulting from (previous) cleaning tests, (partial) varnish removal, and possibly dirt and material degradation. Furthermore, CGT can elucidate topographical issues such as bulging, and losses, and also visualise high-frequency surface variations (e.g. canvas weave and crack pattern). This results in an improvement of documenting a painting’s condition, and the evaluation of treatments and their effects on the visual appearance may be quantified. In conclusion, this research shows that CGT is able to better visualise texture, gloss and colour information than existing techniques like technical photography, facilitating a more precise documentation and localisation of previous and current conservation treatments.

A high-fidelity digital representation of (part of) the human body is a key enabler for integrating humans in a digital twin. Among different parts of human body, building the model of the hand can be a challenging task due to the posture deviations among collected scans. In this article, we proposed a posture invariant statistical shape model (SSM) of the human hand based on 59 3D scans of human hands. First, the 3D scans were spatially aligned using a Möbius sphere-based algorithm. An articulated skeleton, which contains 20 bone segments and 16 joints, was embedded for each 3D scan. Then, all scans were aligned to the same posture using the skeleton and the linear blend skinning (LBS) algorithm. Three methods, i.e., principal component analysis (PCA), kernel-PCA (KPCA) with different kernel functions, and independent component analysis (ICA), were evaluated in the construction of the SSMs regarding the compactness, the generalization ability, and the specificity. The PCA-based SSM was selected, where 20 principal components were used as parameters for the model. Results of the leave-one-out validation indicate that the proposed model was able to fit a given 3D scan of the human hand at an accuracy of 1.21 ± 0.14 mm. Experiment results also indicated that the proposed SSM outperforms the SSM that was built on the scans without posture correction. It is concluded that the proposed posture correction approach can effectively improve the accuracy of the hand SSM and therefore enables its wide usage in human-integrated digital twin applications.

2D coil design limits the use of wireless power transfer (WPT) in many products with freeform outer shapes. In this paper, enabled by 3D printed electronics, we propose a systematic approach to design and fabricate 3D coils for WPT. Based on the circular spiral and rectangular spiral patterns, 3D receiver and transmitter coils can be generated on an arbitrarily selected region of a product and its offset, respectively. Mathematical models are proposed to estimate the self-inductance and the mutual-inductance of the 3D arbitrarily shaped coils for 3D WPT. This leads to a new design approach of a 3D WPT system. Several sets of 3D printed WPT systems were designed, simulated, and prototyped to demonstrate the effectiveness of the proposed design approach as well as the mathematical models. The calculation speed of the proposed mathematical models is 30 times faster than the simulation, and compared with the measurement results, the calculation results have mean absolute errors of 2.63% and 4.45% regarding the self- and the mutual-inductance, where the simulation results have mean absolute errors of 1.20% and 2.38%, respectively. Measurements also indicate that with a 5V input, the prototypes are able to deliver 1-watt power at an efficiency ranging between 20.9% and 25.3%. It was concluded that the proposed approach is feasible and promising for designing and manufacturing WPT using 3D printed electronics.

A seventeenth-century canvas painting is usually comprised of varnish and (translucent) paint layers on a substrate. A viewer’s perception of a work of art can be affected by changes in and damages to these layers. Crack formation in the multi-layered stratigraphy of the painting is visible in the surface topology. Furthermore, the impact of mechanical abrasion, (photo)chemical processes and treatments can affect the topography of the surface and thereby its appearance. New technological advancements in non-invasive imaging allow for the documentation and visualisation of a painting’s 3D shape across larger segments or even the complete surface. In this manuscript we compare three 3D scanning techniques, which have been used to capture the surface topology of Girl with a Pearl Earring by Johannes Vermeer (c. 1665): a painting in the collection of the Mauritshuis, the Hague. These three techniques are: multi-scale optical coherence tomography, 3D scanning based on fringe-encoded stereo imaging (at two resolutions), and 3D digital microscopy. Additionally, scans were made of a reference target and compared to 3D data obtained with white-light confocal profilometry. The 3D data sets were aligned using a scale-invariant template matching algorithm, and compared on their ability to visualise topographical details of interest. Also the merits and limitations for the individual imaging techniques are discussed in-depth. We find that the 3D digital microscopy and the multi-scale optical coherence tomography offer the highest measurement accuracy and precision. However, the small field-of-view of these techniques, makes them relatively slow and thereby less viable solutions for capturing larger (areas of) paintings. For Girl with a Pearl Earring we find that the 3D data provides an unparalleled insight into the surface features of this painting, specifically related to ‘moating’ around impasto, the effects of paint consolidation in earlier restoration campaigns and aging, through visualisation of the crack pattern. Furthermore, the data sets provide a starting point for future documentation and monitoring of the surface topology changes over time. These scans were carried out as part of the research project ‘The Girl in the Spotlight’.