Publikationen von Maximilian Schrapel


  • Refining Vision Videos
    Maximilian Schrapel, Kurt Schneider, Melanie Busch, Oliver Karras and Michael Rohs
    Complex software-based systems involve several stakeholders, their activities and interactions with the system. Vision videos are used during the early phases of a project to complement textual representations. They visualize previously abstract visions of the product and its use. By creating, elaborating, and discussing vision videos, stakeholders and developers gain an improved shared understanding of how those abstract visions could translate into concrete scenarios and requirements to which individuals can relate. [Question/problem] In this paper, we investigate two aspects of refining vision videos: (1) Refining the vision by providing alternative answers to previously open issues about the system to be built. (2) A refined understanding of the camera perspective in vision videos. The impact of using a subjective (or “ego”) perspective is compared to the usual third-person perspective. [Methodology] We use shopping in rural areas as a real-world application domain for refining vision videos. Both aspects of refining vision videos were investigated in an experiment with 20 participants. [Contribution] Subjects made a significant number of additional contributions when they had received not only video or text but also both – even with very short text and short video clips. Subjective video elements were rated as positive. However, there was no significant preference for either subjective or non-subjective videos in general.


  • Pentelligence: Combining Pen Tip Motion and Writing Sounds for Handwritten Digit Recognition
    Maximilian Schrapel, Max-Ludwig Stadler and Michael Rohs
    Proceedings of the 2018 CHI Conference on Human Factors in Computing Systems
    Digital pens emit ink on paper and digitize handwriting. The range of the pen is typically limited to a special writing surface on which the pen's tip is tracked. We present Pentelligence, a pen for handwritten digit recognition that operates on regular paper and does not require a separate tracking device. It senses the pen tip's motions and sound emissions when stroking. Pen motions and writing sounds exhibit complementary properties. Combining both types of sensor data substantially improves the recognition rate. Hilbert envelopes of the writing sounds and mean-filtered motion data are fed to neural networks for majority voting. The results on a dataset of 9408 handwritten digits taken from 26 individuals show that motion+sound outperforms single-sensor approaches at an accuracy of 78.4% for 10 test users. Retraining the networks for a single writer on a dataset of 2120 samples increased the precision to 100% for single handwritten digits at an overall accuracy of 98.3%.
  • International Workshop on Integrating Physical Activity and Health Aspects in Everyday Mobility
    Maximilian Schrapel, Anne Finger, Jochen Meyer, Michael Rohs, Johannes Schoening and Alexandra Voit
    Accepted Workshops at Ubicomp 2018
    Everyday mobility encompasses different forms of public and private transportation and different forms of physical activity. However, in general everyday mobility does not involve substantial levels of physical activity. There are sometimes structural reasons or a lack of motivation and time to realize an active lifestyle in the context of mobility. The goal of this workshop is to investigate ways to integrate physical activity into everyday mobility in accordance with widely accepted health recommendations. We aim to explore wearable and ambient systems that sense and support active navigation as well as conceptual aspects from a variety of perspectives, such as persuasive technologies, and thus invite researchers from different disciplines to contribute their point of view by means of position papers, posters, and demonstrations. One planned outcome of this workshop is a set of design guidelines for navigation systems that explicitly consider health aspects. For the full-day workshop we aim to explore requirements and design challenges in a creative setting.
  • Integrating Recommended Physical Activity in Everyday Mobility
    Maximilian Schrapel, Anne Finger and Michael Rohs
    Accepted Workshoppapers at the workshop on Augmented Humanity using Wearable and Mobile Devices for Health and Wellbeing at MobileHCI'18
    Nowadays, wearables can easily monitor and display physical activities throughout the day. Health recommendations are often used to set daily goals, but these barely take individual requirements into account. In addition, due to limited individual adaptability, there are various life situations in which these goals are not achieved due to missing motivation or time. In this position paper we discuss in particular how health recommendations can be integrated into everyday life and what challenges arise. We also address spatial requirements that are necessary for an active lifestyle.
  • Fußverkehr als Beitrag zur Gesunden Stadt
    Maximilian Schrapel, Anne Finger and Lena Greinke
    Bewegungsmangel ist laut WHO zu einem der führenden Risikofaktoren für gesundheitliche Probleme geworden (WHO 2007: 8) und resultiert aus unserer veränderten Lebens- und Arbeitswelt mit langen körperlichen Ruhezeiten. Neben diesen Phasen, die beispielsweise sitzend am Büroarbeitsplatz verbracht werden, spielt hierbei auch unser Mobilitätsverhalten eine zentrale Rolle. Knapp die Hälfte der Wege, die mit dem Automobil zurückgelegt werden, sind fünf Kilometer lang oder kürzer (infas & DLR 2010, 41). Diese Streckenlängen können auch durch Fuß- und Radverkehr als Bestandteile der aktiven Mobilität geleistet werden. An dieser Stelle setzt das Forschungsprojekt „Aktive Navigation“ der Forschungsinitiative „Mobiler Mensch: Intelligente Mobilität in der Balance von Autonomie, Vernetzung und Security“ der Leibniz Universität Hannover an. Aufbauend auf der Nutzung von Wearables und Smartphones wird eine App entwickelt, die basierend auf der Vorhersage der täglichen Aktivität der Nutzenden eine Route zum Ziel auswählt. Die Routenwahl schließt andere Verkehrsmittel mit ein, soll insgesamt aber dazu dienen, die tägliche Schrittzahl und damit die körperliche Aktivität zu erhöhen.