@inproceedings{Goetzelmann2013, author = {G{\"o}tzelmann, Timo}, title = {Concept of the Joint Use of Smartphone Camera and Projector for Keyboard Inputs}, publisher = {Gediz University Press}, address = {Gediz}, issn = {2147-9097}, pages = {52 - 57}, year = {2013}, abstract = {The efficiency of text input by today's smartphones is significantly limited by the small extents of the virtual keyboard displayed for allowing alphanumeric inputs. Future smartphones will integrate projectors which allow to project multimedia content as well as the smartphones' dialogs. This paper introduces a concept to project the whole smartphone's display onto a surface allowing the user to realize text inputs by interacting with the virtual keyboard projection. This projection is analyzed by standard image processing algorithms. Finally, an experimental implementation shows the feasibility of this concept.}, subject = {Mensch-Maschine-Kommunikation}, language = {en} } @inproceedings{LyKargKreimeieretal.2022, author = {Ly, Kim and Karg, Pascal and Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {Development and Evaluation of a Low-cost Wheelchair Simulator for the Haptic Rendering of Virtual Road Conditions}, series = {Proceedings of the 15th International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {Proceedings of the 15th International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3529190.3529195}, pages = {32 -- 39}, year = {2022}, abstract = {Many streets and buildings are not accessible for wheelchair users, which impedes a major challenge for their mobility. Often, such challenges can be considered during the planning stage, which is why it is important to include this user group in the planning process. Ideally, these planning efforts should also be made visually and haptically navigable using Virtual Reality (VR) technology to allow for better imagination, accurate conclusions, and awareness of wheelchair users. This work optimizes previous approaches so that different roadway conditions can be made haptically perceptible. The proposed prototype provides a non-contact and adjustable brake for simulating inclined planes, which can be adjusted depending on personal and environmental parameters. In addition, it can simulate roads such as cobblestones using a tactile transducer. The individually optimized components were combined into a complete VR system and integrated into a virtual environment for evaluation. The qualitative and quantitative results showed that realistic simulation is possible, but further development steps towards holistic and dissemination-capable hardware and software are needed. To this end, our contribution aims to improve the long-term involvement of wheelchair users in planning processes and increase awareness of their mobility situation.}, language = {en} } @article{KreimeierBielmeierGoetzelmann2018, author = {Kreimeier, Julian and Bielmeier, Thomas and G{\"o}tzelmann, Timo}, title = {Evaluation of Capacitive Markers Fabricated by 3D Printing, Laser Cutting and Prototyping}, series = {Inventions: Special Issue Innovations in 3-D Printing}, volume = {2018}, journal = {Inventions: Special Issue Innovations in 3-D Printing}, number = {Volume 3, Issue 1, Article 9}, publisher = {MDPI}, doi = {10.3390/inventions3010009}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:92-opus4-5603}, pages = {18}, year = {2018}, abstract = {With Tangible User Interfaces, the computer user is able to interact in a fundamentally different and more intuitive way than with usual 2D displays. By grasping real physical objects, information can also be conveyed haptically, i.e., the user not only sees information on a 2D display, but can also grasp physical representations. To recognize such objects ("tangibles") it is skillful to use capacitive sensing, as it happens in most touch screens. Thus, real objects can be located and identified by the touch screen display automatically. Recent work already addressed such capacitive markers, but focused on their coding scheme and automated fabrication by 3D printing. This paper goes beyond the fabrication by 3D printers and, for the first time, applies the concept of capacitive codes to laser cutting and another immediate prototyping approach using modeling clay. Beside the evaluation of additional properties, we adapt recent research results regarding the optimized detection of tangible objects on capacitive screens. As a result of our comprehensive study, the detection performance is affected by the type of capacitive signal processing (respectively the device) and the geometry of the marker. 3D printing revealed to be the most reliable technique, though laser cutting and immediate prototyping of markers showed promising results. Based on our findings, we discuss individual strengths of each capacitive marker type.}, language = {en} } @inproceedings{KreimeierHammerFriedmannetal.2019, author = {Kreimeier, Julian and Hammer, Sebastian and Friedmann, Daniel and Karg, Pascal and B{\"u}hner, Clemens and Bankel, Lukas and G{\"o}tzelmann, Timo}, title = {Evaluation of Different Types of Haptic Feedback Influencing the Task-based Presence and Performance in Virtual Reality}, series = {Proceedings of the 12th ACM International Conference on PErvasive Technologies Related to Assistive Environments (PETRA'19)}, booktitle = {Proceedings of the 12th ACM International Conference on PErvasive Technologies Related to Assistive Environments (PETRA'19)}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-6232-0}, doi = {10.1145/3316782.3321536}, pages = {289 -- 298}, year = {2019}, abstract = {Haptic feedback may support immersion and presence in virtual reality (VR) environments. The emerging market of consumer devices offers first devices which are expected to increase the degree of feeling being actually present in a virtual environment. In this paper we introduce a novel evaluation that examines the influence of different types of haptic feedback on presence and performance regarding manual tasks in VR. Therefore, we conducted a comprehensive user study involving 14 subjects, who performed throwing, stacking and object identification tasks in VR with visual (i.e., sensory substitution), vibrotactile or force feedback. We measured the degree of presence and task-related performance metrics. Our results indicate that regarding presence vibrotactile feedback outperforms haptic feedback which performs better than visual feedback only. In addition, force feedback significantly lowered the execution time for the throwing and the stacking task. In object identification tasks, the vibrotactile feedback increased the detection rates compared to the vibrotactile and force feedback, but also increased the required time of identification. Despite the inadequacies of the still young consumer technology, there were nevertheless strong indications of connections between presence, task fulfillment and the type of haptic feedback.}, language = {en} } @inproceedings{KreimeierGoetzelmann2018, author = {Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {FeelVR: Haptic Exploration of Virtual Objects}, series = {Proceedings of the 11th PErvasive Technologies Related to Assistive Environments Conference (PETRA '18)}, volume = {2018}, booktitle = {Proceedings of the 11th PErvasive Technologies Related to Assistive Environments Conference (PETRA '18)}, publisher = {ACM}, address = {New York}, isbn = {978-1-4503-6390-7}, doi = {10.1145/3197768.3201526}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:92-opus4-5611}, pages = {122 -- 125}, year = {2018}, abstract = {The interest in virtual and augmented reality increased rapidly in the last years. Recently, haptic interaction and its applications get into focus. In this paper, we suggest the exploration of virtual objects using off-the-shelf VR game controllers. These are held like a pen with both hands and were used to palpate and identify the virtual object. Our study largely coincides with comparable previous work and shows that a ready-to-use VR system can be basically used for haptic exploration. The results indicate that virtual objects are more effectively recognized with closed eyes than with open eyes. In both cases, objects with a bigger morphological difference were identified the most frequently. The limitations due to quality and quantity of tactile feedback should be tackled in future studies that utilize currently developed wearable haptic devices and haptic rendering involving all fingers or even both hands. Thus, objects could be identifiable more intuitively and haptic feedback devices for interacting with virtual objects will be further disseminated.}, language = {en} } @inproceedings{KreimeierGoetzelmann2019, author = {Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {First Steps Towards Walk-In-Place Locomotion and Haptic Feedback in Virtual Reality for Visually Impaired}, series = {CHI EA '19: Extended Abstracts of the 2019 CHI Conference on Human Factors in Computing Systems}, volume = {2019}, booktitle = {CHI EA '19: Extended Abstracts of the 2019 CHI Conference on Human Factors in Computing Systems}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-5971-9}, doi = {10.1145/3290607.3312944}, pages = {1 -- 6}, year = {2019}, abstract = {This paper presents the first results on a user study in which people with visual impairments (PVI) explored a virtual environment (VE) by walking in a virtual reality (VR) treadmill. As recently suggested, we have now acquired first results from our feasibility study investigating this walk-in-place interaction. This represents a new, more intuitive way of for example virtually exploring unknown spaces in advance. Our prototype consists of off-the-shelf VR components (i.e., treadmill, headphones, glasses, and controller) providing a simplified white cane simulation and was tested by six visually impaired subjects. Our results indicate that this interaction is yet difficult, but promising and an important step to make VR more and better usable for PVIs. As an impact on the CHI community, we would like to make this research field known to a wider audience by sharing our intermediate results and suggestions for improvements, on some of which we are already working on.}, language = {en} } @inproceedings{OumardKreimeierGoetzelmann2022, author = {Oumard, Christina and Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {Implementation and Evaluation of a Voice User Interface with Offline Speech Processing for People who are Blind or Visually Impaired}, series = {Proceedings of the 15th International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {Proceedings of the 15th International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3529190.3529197}, pages = {277 -- 285}, year = {2022}, abstract = {Assistive technologies help blind and visually impaired people to manage their daily lives independently. However, they usually have to work with voice user interfaces to use smartphones and tablets. Tasks like managing the calendar, taking notes, or setting an alarm clock require reliable voice recognition, which entails online access for remote computing. However, apart from data privacy and security issues, an online connection is not available in any situation. In this regard, our paper develops and evaluates an offline voice user interface with offline speech processing. The voice assistant was tested with seven blind and visually impaired people. It was found that the assistant was very well received (i.e., pragmatic, hedonic, and general quality) and that no functional limitations could be perceived due to the offline data processing. Based on these findings, the scope of functionality and the level of detail of the evaluation can be extended further to adapt this technology for this specific user group and promote its dissemination.}, language = {en} } @inproceedings{GoetzelmannVazquez2015, author = {G{\"o}tzelmann, Timo and V{\´a}zquez, Pere-Pau}, title = {InclineType: An Accelerometer-based Typing Approach for Smartwatches}, series = {Proc. 16th International Conference on Human Computer Interaction}, volume = {2015}, booktitle = {Proc. 16th International Conference on Human Computer Interaction}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-3463-1}, doi = {10.1145/2829875.2829929}, year = {2015}, abstract = {Small mobile devices such as smartwatches are a rapidly growing market. However, they share the issue of limited input and output space which could impede the success of these devices in future. Hence, suitable alternatives to the concepts and metaphors known from smartphones have to be found. In this paper we present InclineType a tilt-based keyboard input that uses a 3-axis accelerometer for smartwatches. The user may directly select letters by moving his/her wrist and enters them by tapping on the touchscreen. Thanks to the distribution of the letters on the edges of the screen, the keyboard dedicates a low amount of space in the smartwatch. In order to optimize the user input our concept proposes multiple techniques to stabilize the user interaction. Finally, a user study shows that users get familiar with this technique with almost no previous training, reaching speeds of about 6 wpm in average.}, language = {en} } @inproceedings{KreimeierUllmannKipkeetal.2020, author = {Kreimeier, Julian and Ullmann, Daniela and Kipke, Harald and G{\"o}tzelmann, Timo}, title = {Initial Evaluation of Different Types of Virtual Reality Locomotion Towards a Pedestrian Simulator for Urban and Transportation Planning}, series = {Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems}, booktitle = {Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3334480.3382958}, pages = {1 -- 6}, year = {2020}, abstract = {The simulation of human behaviour in today's travel demand models is usually based on the assumption of a rational behaviour of its participants. Since travel demand models have been applied in particular for motorized traffic, only little is known about the influence of variables that affect both the choice of trip destination and the route decision in pedestrian and cycling models. In order to create urban spaces that encourage cycling and walking, we propose a VR (Virtual Reality) pedestrian simulator which involves walk-in-place locomotion. Thus, identical conditions are obtained for all subjects which is not feasible in real world field research with naturally varying environmental influences. As a first step, our qualitative and quantitative user study revealed that walking in a VR treadmill felt safest and most intuitive, although walking in it took in return more energy than walking-in-place with VR trackers only.}, language = {en} } @inproceedings{Goetzelmann2014, author = {G{\"o}tzelmann, Timo}, title = {Interactive Tactile Maps for Blind People using Smartphones' Integrated Cameras}, series = {Proc. 9th ACM International Conference on Interactive Tabletops and Surfaces (ITS'14)}, volume = {2014}, booktitle = {Proc. 9th ACM International Conference on Interactive Tabletops and Surfaces (ITS'14)}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-2587-5}, doi = {10.1145/2669485.2669550}, pages = {381 -- 385}, year = {2014}, abstract = {Tactile maps may support blind persons in orientation and understanding geographical relations, but their availability is still very limited. However, recent technologies such as 3D printers allow to autonomously print individual tactile maps which can be linked with interactive applications. Besides geographical depictions, textual annotation of maps is crucial. However, this often adds much complexity to tactile maps. To limit tactile complexity, interactive approaches may help to complement maps by the auditive modality. The presented approach integrates barcodes into tactile maps to allow their detection by standard smartphones' cameras. Automatically, more detailed map data is obtained to auditively support the exploration of the tactile map. Our experimental implementation shows the principal feasibility and provides the basis of ongoing comprehensive user studies.}, language = {en} } @inproceedings{Goetzelmann2016, author = {G{\"o}tzelmann, Timo}, title = {LucentMaps: 3D Printed Audiovisual Tactile Maps for Blind and Visually Impaired People}, series = {ASSETS '16: Proceedings of the 18th International ACM SIGACCESS Conference on Computers and Accessibility}, volume = {2016}, booktitle = {ASSETS '16: Proceedings of the 18th International ACM SIGACCESS Conference on Computers and Accessibility}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-4124-0}, doi = {10.1145/2982142.2982163}, pages = {81 -- 90}, year = {2016}, abstract = {Tactile maps support blind and visually impaired people in orientation and to familiarize with unfamiliar environments. Interactive approaches complement these maps with auditory feedback. However, commonly these approaches focus on blind people. We present an approach which incorporates visually impaired people by visually augmenting relevant parts of tactile maps. These audiovisual tactile maps can be used in conjunction with common tablet computers and smartphones. By integrating conductive elements into 3D printed tactile maps, they can be recognized by a single touch on the mobile device's display, which eases the handling for blind and visually impaired people. To allow multiple elevation levels in our transparent tactile maps, we conducted a study to reconcile technical and physiological requirements of off-the-shelf 3D printers, capacitive touch inputs and the human tactile sense. We propose an interaction concept for 3D printed audiovisual tactile maps, verify its feasibility and test it with a user study. Our discussion includes economic considerations crucial for a broad dissemination of tactile maps for both blind and visually impaired people.}, language = {en} } @inproceedings{GoetzelmannKreimeier2020, author = {G{\"o}tzelmann, Timo and Kreimeier, Julian}, title = {Optimization of navigation considerations of people with visual impairments through ambient intelligence}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3389189.3398009}, pages = {1 -- 6}, year = {2020}, abstract = {As urbanization progresses, cities are becoming increasingly complex. To make this complexity advantageous, Smart Cities integrate intelligent sensors that communicate with each other and are invisible to citizens, so that they can offer additional services. Despite the fact that the inclusion of diverse citizens is an essential requirement of Smart Cities, Ambient Intelligence is often not considered under accessibility aspects. The central question in this context is how disadvantaged groups in particular can benefit from Smart Cities. It is extremely important for people with disabilities to be able to move autonomously in public spaces. For this purpose, however, people who are blind sometimes need to be able to ask other people for directions. Knowing whether people are present can be important information. In our exemplary case study, Ambient Intelligence is used for people with visual impairments, so that they can decide whether they want to go to this or an alternative place based on the information about the density of people in a place.}, language = {en} } @incollection{OumardKreimeierGoetzelmann2022, author = {Oumard, Christina and Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {Pardon? An Overview of the Current State and Requirements of Voice User Interfaces for Blind and Visually Impaired Users}, series = {Lecture Notes in Computer Science}, booktitle = {Lecture Notes in Computer Science}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {9783031086472}, issn = {0302-9743}, doi = {10.1007/978-3-031-08648-9_45}, pages = {388 -- 398}, year = {2022}, abstract = {People with special needs like blind and visually impaired (BVI) people can particularly benefit from using voice assistants providing spoken information input and output in everyday life. However, it is crucial to understand their needs and include them in developing accessible and useful assistance systems. By conducting an online survey with 146 BVI people, this paper revealed that common voice assistants like Apple's Siri or Amazon's Alexa are used by a majority of BVI people and are also considered helpful. In particular, features in audio entertainment, internet access, and everyday life practical things like weather queries, time-related information (e.g., setting an alarm clock), checking calendar entries, and taking notes are particularly often used and appreciated. The participants also indicated that the integration of smart home devices, the optimization of existing functionalities, and voice input are important. Still, also potentially negative aspects such as data privacy and data security are relevant. Therefore, it seems particularly interesting to implement offline data processing as far as possible. Our results contribute to this development by providing an overview of empirically collected requirements for functions and implementation-related aspects.}, language = {en} } @inproceedings{GoetzelmannKreimeier2020, author = {G{\"o}tzelmann, Timo and Kreimeier, Julian}, title = {Participation of elderly people in smart city planning by means of virtual reality}, series = {Proceedings of the 13th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {Proceedings of the 13th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3389189.3397649}, pages = {1 -- 2}, year = {2020}, abstract = {Urbanisation is progressing, the population in many countries has a growing proportion of old people. This must be taken into account when transforming urban environments into Smart Cities. On the one hand, general accessibility rules must be taken into account in the planning of buildings and urban environments. However, an essential requirement for transformation is the participation of citizens, i.e., concrete suggestions for improvement from citizen should be taken into account. Elderly people are a valuable source of information for improvements. Instead of simply involving them in the modification of existing facilities, our approach suggests that they should be included in the planning process. However, abstract plans and questionnaires allow only limited insights for ordinary citizen. Therefore, our approach aims at providing a suitable interface to interactively walk through and annotate virtual reality plans for buildings and city districts. We present a working prototype for elderly people based on 3D consumer hardware appropriate form of locomotion with which they can explore and annotate urban planning according to their individual needs.}, language = {en} } @inproceedings{KargStoehrJonasetal.2023, author = {Karg, Pascal and St{\"o}hr, Roman and Jonas, Lisa and Kreimeier, Julian and G{\"o}tzelmann, Timo}, title = {Reflect-AR: Insights into Mirror-Based Augmented Reality Instructions to Support Manual Assembly Tasks}, series = {Proceedings of the 16th International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {Proceedings of the 16th International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3594806.3594866}, pages = {62 -- 68}, year = {2023}, abstract = {Manual assembly tasks can be difficult and tedious without assistance. Here, augmented reality (AR) can help to ease the task load and lower the time and error rates by interactive in-situ instructions. Such approaches are often implemented by video or optical see-through AR. In order to test a system that is as low-threshold as possible and easy to implement, we developed a prototype with a mirror display supplemented by a RGB-D camera and evaluated it against an well-established AR HMD (HoloLens 2). For this purpose, in our study 10 participants placed 3D printed bricks via both technologies. The quantitative and qualitative analysis revealed that the fulfillment of this task with a professional, established product AR HMD yet remains unmatched in terms of the time required, error rate, usability and task load due to the prototype status and the remaining technical shortcomings. However, the mirror display setup prototype met with interest from the participants as a novel, but unfamiliar and thus more difficult to use way of interaction. Furthermore, we report implementation challenges and advises. The empirical insights of our prototype and the first-time comparison to an established AR HMD aims to foster refining future work with half-silvered AR mirrors as an little researched field and many different fields of application.}, language = {en} } @inproceedings{DeitschGoetzelmannGallwitz2014, author = {Deitsch, Sergiu and G{\"o}tzelmann, Timo and Gallwitz, Florian}, title = {Smartphone Input Using Its Integrated Projector and Built-In Camera}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-07226-5}, doi = {10.1007/978-3-319-07227-2_13}, pages = {124 -133}, year = {2014}, abstract = {Touch input on modern smartphones can be tedious, especially if the touchscreen is small. Smartphones with integrated projectors can be used to overcome this limitation by projecting the screen contents onto a surface, allowing the user to interact with the projection by means of simple hand gestures. In this work, we propose a novel approach for projector smartphones that allows the user to remotely interact with the smartphone screen via its projection. We detect user's interaction using the built-in camera, and forward detected hand gestures as touch input events to the operating system. In order to avoid costly computations, we additionally use built-in motion sensors. We verify the proposed method using an implementation for the consumer smartphone Samsung Galaxy Beam equipped with a deflection mirror. © 2014 Springer International Publishing.}, subject = {App }, language = {en} } @inproceedings{GoetzelmannWinkler2015, author = {G{\"o}tzelmann, Timo and Winkler, Klaus}, title = {SmartTactMaps: A Smartphone-Based Approach to Support Blind Persons in Exploring Tactile Maps}, series = {Proc. 8th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, volume = {2015}, booktitle = {Proc. 8th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-3452-5}, doi = {10.1145/2769493.2769497}, pages = {8}, year = {2015}, abstract = {Despite increasing digitalization of our society many blind persons still have very limited access to predominantly pictorial information such as maps. In this paper we introduce a novel approach to improve the accessibility of maps for blind users by utilizing the abilities of standard smartphones. A major issue of tactile maps is the limited discriminability of the humans' tactile sense. Textual annotation of maps is crucial, but adds much complexity to tactile maps. Additionally, only few Braille labels can be accommodated to maintain legibility. In our approach we link smartphones with adapted tactile maps which transforms the physical maps into interactive surfaces using both the tactile and the auditory modality. We integrate machine readable metadata into these maps which can be recognized by the smartphones' camera to immediately obtain detailed map descriptions from a free global database. During tactile exploration of the map, blind users can request auditory explanations by interacting with the mobile application. An experimental application and a user study demonstrate the feasibility of our approach.}, language = {en} } @inproceedings{KreimeierKargGoetzelmann2020, author = {Kreimeier, Julian and Karg, Pascal and G{\"o}tzelmann, Timo}, title = {Tabletop virtual haptics}, series = {Proceedings of the 13th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, booktitle = {Proceedings of the 13th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, doi = {10.1145/3389189.3389194}, pages = {1 -- 10}, year = {2020}, abstract = {When thinking of Virtual Reality (VR), most people think of stunning audio-visual environments in the context of entertainment. However, VR can also provide haptic information, e.g., to convey spatial information to blind and visually impaired people. In this context of accessibility they might be able to explore independently and self-determined tactile graphics, e.g., the structure of unknown real places prior to visiting them. Thus, we propose and evaluate tabletop virtual objects that can be felt by nowadays commercially available VR components, instead of exploring physical models (e.g., 3D printed maps) with the bare hand. These can be easily placed on an empty table, giving the blind user faster and more independent access to tactile information than with real physical representations. Our comprehensive pilot user study shows that it is possible to recognize floor plans and simple geometric shapes in this context. Also, the insights gained with regard to the suitability for practical application in this context point out the way to eased access to spatial (virtual) information using off-the-shelf components which can significantly support blind and visually impaired users' autonomy.}, language = {en} } @inproceedings{GoetzelmannAlthaus2016, author = {G{\"o}tzelmann, Timo and Althaus, Christopher}, title = {TouchSurfaceModels: Capacitive Sensing Objects through 3D Printers}, series = {PETRA '16: Proceedings of the 9th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, volume = {2016}, booktitle = {PETRA '16: Proceedings of the 9th ACM International Conference on PErvasive Technologies Related to Assistive Environments}, publisher = {ACM}, address = {New York, NY, USA}, isbn = {978-1-4503-4337-4}, pages = {8}, year = {2016}, abstract = {Nowadays, 3D models can be downloaded from the internet and increasingly be printed by low cost 3D printers. In the future, blind people could benefit from this tendency. Unfortunately, many of these models are rather complex and not appropriate for the purely tactile exploration. To obtain quantitative data about how 3D printable models for blind people should be constructed, the tactile exploration can be recorded by video. However, the analysis of these videos is quite time consuming and expensive. Additionally, inaccuracies and masking effects may impede the use of this technique. In this paper we introduce a novel approach to automatically equip existing 3D models with a mesh of conductive wires which enable a touch sensitive surface for the printed 3D objects. These touch sensing 3D models can be printed in one turn by off-the-shelf 3D printers and used as an alternative to video recording. It allows exact registration of when and where the 3D object has been touched. In our multi-touch solution, particular attention has been paid to limit the number of necessary wires between 3D object and sensing electronics. Finally, our approach is evaluated by a feasibility study.}, language = {en} } @inproceedings{GoetzelmannPavkovic2014, author = {G{\"o}tzelmann, Timo and Pavkovic, Aleksander}, title = {Towards Automatically Generated Tactile Detail Maps by 3D Printers for Blind Persons}, series = {Computers Helping People with Special Needs}, booktitle = {Computers Helping People with Special Needs}, publisher = {Springer}, isbn = {978-3-319-08599-9}, doi = {10.1007/978-3-319-08599-9_1}, pages = {1-7}, year = {2014}, abstract = {This paper introduces an approach for the (semi)automatic generation of worldwide available, detailed tactile maps including buildings and blind-specific features based on recognized illustrators' guidelines and standards. These guidelines for tactile maps are investigated in order to define a formal rule set and to automatically filter map data accordingly. Using the rule set, our approach automatically abstracts map data in order to generate a 2.1D tactile model providing multiple height levels (layers) which can be printed by usual consumer 3D printers. Based on the popular OpenStreetMap map data, our automated approach allows to generate arbitrary detail maps blind persons individually interested in, without the need for manual adaption of the tactile map. Thus, this approach contributes to the goal to increase the autonomy of blind persons.}, subject = {3D-Drucker}, language = {en} }