The Feeling of Color: A Haptic Feedback Device for the Visually Disabled

Tapson J, Gurari N, Diaz J, et al. The Feeling of Color: A Haptic Feedback Device for the Visually Disabled. Presented at the Biomedical Circuits and Systems Conference (BIOCAS), Baltimore, MD.We describe a sensory augmentation system designed to provide the visually disabled with a sense of color. Our system consists of a glove with short-range optical color sensors mounted on its fingertips, and a torso-worn belt on which tactors (haptic feedback actuators) are mounted. Each fingertip sensor detects the observed objectpsilas color. This information is encoded to the tactor through vibrations in respective locations and varying modulations. Early results suggest that detection of primary colors is possible with near 100% accuracy and moderate latency, with a minimum amount of training

인간 기계 상호작용을 위한 강건하고 정확한 손동작 추적 기술 연구

학위논문(박사) -- 서울대학교대학원 : 공과대학 기계항공공학부, 2021.8. 이동준.Hand-based interface is promising for realizing intuitive, natural and accurate human machine interaction (HMI), as the human hand is main source of dexterity in our daily activities. For this, the thesis begins with the human perception study on the detection threshold of visuo-proprioceptive conflict (i.e., allowable tracking error) with or without cutantoues haptic feedback, and suggests tracking error specification for realistic and fluidic hand-based HMI. The thesis then proceeds to propose a novel wearable hand tracking module, which, to be compatible with the cutaneous haptic devices spewing magnetic noise, opportunistically employ heterogeneous sensors (IMU/compass module and soft sensor) reflecting the anatomical properties of human hand, which is suitable for specific application (i.e., finger-based interaction with finger-tip haptic devices). This hand tracking module however loses its tracking when interacting with, or being nearby, electrical machines or ferromagnetic materials. For this, the thesis presents its main contribution, a novel visual-inertial skeleton tracking (VIST) framework, that can provide accurate and robust hand (and finger) motion tracking even for many challenging real-world scenarios and environments, for which the state-of-the-art technologies are known to fail due to their respective fundamental limitations (e.g., severe occlusions for tracking purely with vision sensors; electromagnetic interference for tracking purely with IMUs (inertial measurement units) and compasses; and mechanical contacts for tracking purely with soft sensors). The proposed VIST framework comprises a sensor glove with multiple IMUs and passive visual markers as well as a head-mounted stereo camera; and a tightly-coupled filtering-based visual-inertial fusion algorithm to estimate the hand/finger motion and auto-calibrate hand/glove-related kinematic parameters simultaneously while taking into account the hand anatomical constraints. The VIST framework exhibits good tracking accuracy and robustness, affordable material cost, light hardware and software weights, and ruggedness/durability even to permit washing. Quantitative and qualitative experiments are also performed to validate the advantages and properties of our VIST framework, thereby, clearly demonstrating its potential for real-world applications.손 동작을 기반으로 한 인터페이스는 인간-기계 상호작용 분야에서 직관성, 몰입감, 정교함을 제공해줄 수 있어 많은 주목을 받고 있고, 이를 위해 가장 필수적인 기술 중 하나가 손 동작의 강건하고 정확한 추적 기술 이다. 이를 위해 본 학위논문에서는 먼저 사람 인지의 관점에서 손 동작 추적 오차의 인지 범위를 규명한다. 이 오차 인지 범위는 새로운 손 동작 추적 기술 개발 시 중요한 설계 기준이 될 수 있어 이를 피험자 실험을 통해 정량적으로 밝히고, 특히 손끝 촉각 장비가 있을때 이 인지 범위의 변화도 밝힌다. 이를 토대로, 촉각 피드백을 주는 것이 다양한 인간-기계 상호작용 분야에서 널리 연구되어 왔으므로, 먼저 손끝 촉각 장비와 함께 사용할 수 있는 손 동작 추적 모듈을 개발한다. 이 손끝 촉각 장비는 자기장 외란을 일으켜 착용형 기술에서 흔히 사용되는 지자기 센서를 교란하는데, 이를 적절한 사람 손의 해부학적 특성과 관성 센서/지자기 센서/소프트 센서의 적절한 활용을 통해 해결한다. 이를 확장하여 본 논문에서는, 촉각 장비 착용 시 뿐 아니라 모든 장비 착용 / 환경 / 물체와의 상호작용 시에도 사용 가능한 새로운 손 동작 추적 기술을 제안한다. 기존의 손 동작 추적 기술들은 가림 현상 (영상 기반 기술), 지자기 외란 (관성/지자기 센서 기반 기술), 물체와의 접촉 (소프트 센서 기반 기술) 등으로 인해 제한된 환경에서 밖에 사용하지 못한다. 이를 위해 많은 문제를 일으키는 지자기 센서 없이 상보적인 특성을 지니는 관성 센서와 영상 센서를 융합하고, 이때 작은 공간에 다 자유도의 움직임을 갖는 손 동작을 추적하기 위해 다수의 구분되지 않는 마커들을 사용한다. 이 마커의 구분 과정 (correspondence search)를 위해 기존의 약결합 (loosely-coupled) 기반이 아닌 강결합 (tightly-coupled 기반 센서 융합 기술을 제안하고, 이를 통해 지자기 센서 없이 정확한 손 동작이 가능할 뿐 아니라 착용형 센서들의 정확성/편의성에 문제를 일으키던 센서 부착 오차 / 사용자의 손 모양 등을 자동으로 정확히 보정한다. 이 제안된 영상-관성 센서 융합 기술 (Visual-Inertial Skeleton Tracking (VIST)) 의 뛰어난 성능과 강건성이 다양한 정량/정성 실험을 통해 검증되었고, 이는 VIST의 다양한 일상환경에서 기존 시스템이 구현하지 못하던 손 동작 추적을 가능케 함으로써, 많은 인간-기계 상호작용 분야에서의 가능성을 보여준다.1 Introduction 1 1.1. Motivation 1 1.2. Related Work 5 1.3. Contribution 12 2 Detection Threshold of Hand Tracking Error 16 2.1. Motivation 16 2.2. Experimental Environment 20 2.2.1. Hardware Setup 21 2.2.2. Virtual Environment Rendering 23 2.2.3. HMD Calibration 23 2.3. Identifying the Detection Threshold of Tracking Error 26 2.3.1. Experimental Setup 27 2.3.2. Procedure 27 2.3.3. Experimental Result 31 2.4. Enlarging the Detection Threshold of Tracking Error by Haptic Feedback 31 2.4.1. Experimental Setup 31 2.4.2. Procedure 32 2.4.3. Experimental Result 34 2.5. Discussion 34 3 Wearable Finger Tracking Module for Haptic Interaction 38 3.1. Motivation 38 3.2. Development of Finger Tracking Module 42 3.2.1. Hardware Setup 42 3.2.2. Tracking algorithm 45 3.2.3. Calibration method 48 3.3. Evaluation for VR Haptic Interaction Task 50 3.3.1. Quantitative evaluation of FTM 50 3.3.2. Implementation of Wearable Cutaneous Haptic Interface 51 3.3.3. Usability evaluation for VR peg-in-hole task 53 3.4. Discussion 57 4 Visual-Inertial Skeleton Tracking for Human Hand 59 4.1. Motivation 59 4.2. Hardware Setup and Hand Models 62 4.2.1. Human Hand Model 62 4.2.2. Wearable Sensor Glove 62 4.2.3. Stereo Camera 66 4.3. Visual Information Extraction 66 4.3.1. Marker Detection in Raw Images 68 4.3.2. Cost Function for Point Matching 68 4.3.3. Left-Right Stereo Matching 69 4.4. IMU-Aided Correspondence Search 72 4.5. Filtering-based Visual-Inertial Sensor Fusion 76 4.5.1. EKF States for Hand Tracking and Auto-Calibration 78 4.5.2. Prediction with IMU Information 79 4.5.3. Correction with Visual Information 82 4.5.4. Correction with Anatomical Constraints 84 4.6. Quantitative Evaluation for Free Hand Motion 87 4.6.1. Experimental Setup 87 4.6.2. Procedure 88 4.6.3. Experimental Result 90 4.7. Quantitative and Comparative Evaluation for Challenging Hand Motion 95 4.7.1. Experimental Setup 95 4.7.2. Procedure 96 4.7.3. Experimental Result 98 4.7.4. Performance Comparison with Existing Methods for Challenging Hand Motion 101 4.8. Qualitative Evaluation for Real-World Scenarios 105 4.8.1. Visually Complex Background 105 4.8.2. Object Interaction 106 4.8.3. Wearing Fingertip Cutaneous Haptic Devices 109 4.8.4. Outdoor Environment 111 4.9. Discussion 112 5 Conclusion 116 References 124 Abstract (in Korean) 139 Acknowledgment 141박

Touch- and Walkable Virtual Reality to Support Blind and Visually Impaired Peoples‘ Building Exploration in the Context of Orientation and Mobility

Der Zugang zu digitalen Inhalten und Informationen wird immer wichtiger für eine erfolgreiche Teilnahme an der heutigen, zunehmend digitalisierten Zivilgesellschaft. Solche Informationen werden meist visuell präsentiert, was den Zugang für blinde und sehbehinderte Menschen einschränkt. Die grundlegendste Barriere ist oft die elementare Orientierung und Mobilität (und folglich die soziale Mobilität), einschließlich der Erlangung von Kenntnissen über unbekannte Gebäude vor deren Besuch. Um solche Barrieren zu überbrücken, sollten technische Hilfsmittel entwickelt und eingesetzt werden. Es ist ein Kompromiss zwischen technologisch niedrigschwellig zugänglichen und verbreitbaren Hilfsmitteln und interaktiv-adaptiven, aber komplexen Systemen erforderlich. Die Anpassung der Technologie der virtuellen Realität (VR) umfasst ein breites Spektrum an Entwicklungs- und Entscheidungsoptionen. Die Hauptvorteile der VR-Technologie sind die erhöhte Interaktivität, die Aktualisierbarkeit und die Möglichkeit, virtuelle Räume und Modelle als Abbilder von realen Räumen zu erkunden, ohne dass reale Gefahren und die begrenzte Verfügbarkeit von sehenden Helfern auftreten. Virtuelle Objekte und Umgebungen haben jedoch keine physische Beschaffenheit. Ziel dieser Arbeit ist es daher zu erforschen, welche VR-Interaktionsformen sinnvoll sind (d.h. ein angemessenes Verbreitungspotenzial bieten), um virtuelle Repräsentationen realer Gebäude im Kontext von Orientierung und Mobilität berührbar oder begehbar zu machen. Obwohl es bereits inhaltlich und technisch disjunkte Entwicklungen und Evaluationen zur VR-Technologie gibt, fehlt es an empirischer Evidenz. Zusätzlich bietet diese Arbeit einen Überblick über die verschiedenen Interaktionen. Nach einer Betrachtung der menschlichen Physiologie, Hilfsmittel (z.B. taktile Karten) und technologischen Eigenschaften wird der aktuelle Stand der Technik von VR vorgestellt und die Anwendung für blinde und sehbehinderte Nutzer und der Weg dorthin durch die Einführung einer neuartigen Taxonomie diskutiert. Neben der Interaktion selbst werden Merkmale des Nutzers und des Geräts, der Anwendungskontext oder die nutzerzentrierte Entwicklung bzw. Evaluation als Klassifikatoren herangezogen. Begründet und motiviert werden die folgenden Kapitel durch explorative Ansätze, d.h. im Bereich 'small scale' (mit sogenannten Datenhandschuhen) und im Bereich 'large scale' (mit einer avatargesteuerten VR-Fortbewegung). Die folgenden Kapitel führen empirische Studien mit blinden und sehbehinderten Nutzern durch und geben einen formativen Einblick, wie virtuelle Objekte in Reichweite der Hände mit haptischem Feedback erfasst werden können und wie verschiedene Arten der VR-Fortbewegung zur Erkundung virtueller Umgebungen eingesetzt werden können. Daraus werden geräteunabhängige technologische Möglichkeiten und auch Herausforderungen für weitere Verbesserungen abgeleitet. Auf der Grundlage dieser Erkenntnisse kann sich die weitere Forschung auf Aspekte wie die spezifische Gestaltung interaktiver Elemente, zeitlich und räumlich kollaborative Anwendungsszenarien und die Evaluation eines gesamten Anwendungsworkflows (d.h. Scannen der realen Umgebung und virtuelle Erkundung zu Trainingszwecken sowie die Gestaltung der gesamten Anwendung in einer langfristig barrierefreien Weise) konzentrieren.Access to digital content and information is becoming increasingly important for successful participation in today's increasingly digitized civil society. Such information is mostly presented visually, which restricts access for blind and visually impaired people. The most fundamental barrier is often basic orientation and mobility (and consequently, social mobility), including gaining knowledge about unknown buildings before visiting them. To bridge such barriers, technological aids should be developed and deployed. A trade-off is needed between technologically low-threshold accessible and disseminable aids and interactive-adaptive but complex systems. The adaptation of virtual reality (VR) technology spans a wide range of development and decision options. The main benefits of VR technology are increased interactivity, updatability, and the possibility to explore virtual spaces as proxies of real ones without real-world hazards and the limited availability of sighted assistants. However, virtual objects and environments have no physicality. Therefore, this thesis aims to research which VR interaction forms are reasonable (i.e., offering a reasonable dissemination potential) to make virtual representations of real buildings touchable or walkable in the context of orientation and mobility. Although there are already content and technology disjunctive developments and evaluations on VR technology, there is a lack of empirical evidence. Additionally, this thesis provides a survey between different interactions. Having considered the human physiology, assistive media (e.g., tactile maps), and technological characteristics, the current state of the art of VR is introduced, and the application for blind and visually impaired users and the way to get there is discussed by introducing a novel taxonomy. In addition to the interaction itself, characteristics of the user and the device, the application context, or the user-centered development respectively evaluation are used as classifiers. Thus, the following chapters are justified and motivated by explorative approaches, i.e., in the group of 'small scale' (using so-called data gloves) and in the scale of 'large scale' (using an avatar-controlled VR locomotion) approaches. The following chapters conduct empirical studies with blind and visually impaired users and give formative insight into how virtual objects within hands' reach can be grasped using haptic feedback and how different kinds of VR locomotion implementation can be applied to explore virtual environments. Thus, device-independent technological possibilities and also challenges for further improvements are derived. On the basis of this knowledge, subsequent research can be focused on aspects such as the specific design of interactive elements, temporally and spatially collaborative application scenarios, and the evaluation of an entire application workflow (i.e., scanning the real environment and exploring it virtually for training purposes, as well as designing the entire application in a long-term accessible manner)

An Ergonomics Investigation of the Application of Virtual Reality on Training for a Precision Task

Virtual reality is rapidly expanding its capabilities and accessibility to consumers. The application of virtual reality in training for precision tasks has been limited to specialized equipment such as a haptic glove or a haptic stylus, but not studied for handheld controllers in consumer-grade systems such as the HTC Vive. A straight-line precision steadiness task was adopted in virtual reality to emulate basic linear movements in industrial operations and disability rehabilitation. This study collected the total time and the error time for the straight-line task in both virtual reality and a physical control experiment for 48 participants. The task was performed at four different gap widths, 4mm, 5mm, 6mm, and 7mm, to see the effects of virtual reality at different levels of precision. Average error ratios were then calculated and analyzed for strong associations to various factors. The results indicated that a combination of Environment x Gap Width factors significantly affected average error ratios, with a p-value of 0.000. This human factors study also collected participants’ ratings of user experience dimensions, such as difficulty, comfort, strain, reliability, and effectiveness, for both physical and virtual environments in a questionnaire. The results indicate that the ratings for difficulty, reliability, and effectiveness were significantly different, with virtual reality rating consistently rating worse than the physical environment. An analysis of questionnaire responses indicates a significant association of overall environment preference (physical or virtual) with performance data, with a p-value of 0.027. In general, virtual reality yielded higher error among participants. As the difficulty of the task increased, the performance in virtual reality degraded significantly. Virtual reality has great potential for a variety of precision applications, but the technology in consumer-grade hardware must improve significantly to enable these applications. Virtual reality is difficult to implement without previous experience or specialized knowledge in programming, which makes the technology currently inaccessible for many people. Future work is needed to investigate a larger variety of precision tasks and movements to expand the body of knowledge of virtual reality applications for training purposes

Sensor-Based Assistive Devices for Visually-Impaired People: Current Status, Challenges, and Future Directions

The World Health Organization (WHO) reported that there are 285 million visually impaired people worldwide. Among these individuals, there are 39 million who are totally blind. There have been several systems designed to support visually-impaired people and to improve the quality of their lives. Unfortunately, most of these systems are limited in their capabilities. In this paper, we present a comparative survey of the wearable and portable assistive devices for visuallyimpaired people in order to show the progress in assistive technology for this group of people. Thus, the contribution of this literature survey is to discuss in detail the most significant devices that are presented in the literature to assist this population and highlight the improvements, advantages, disadvantages, and accuracy. Our aim is to address and present most of the issues of these systems to pave the way for other researchers to design devices that ensure safety and independent mobility to visually-impaired people.https://doi.org/10.3390/s1703056

Sensory Augmentation for Navigation in Difficult Urban Environments by People With Visual Impairment

Independent mobility in completing such tasks as walking through a town centre is taken for granted by well-bodied individuals. However, for those with a disability such as impairment of vision, mobility and navigation can become challenging tasks not easily undertaken. The barriers to access for blind and partially sighted individuals are increased when familiar navigational cues are removed in difficult urban environments such as Shared Space. The research consisted of investigating methods of navigation employed by people with visual impairment and designing a device to restore confidence to this group so as to lower the barriers of access to such environments. Investigation was carried out through the deployment of a questionnaire; discussions with groups representing blind and partially sighted people; and a site visit to Shared Space environments. Statistical analysis was carried out on the results of the questionnaire to ascertain the navigational habits of blind and partially sighted individuals in different environments. From the analysis and the results of the discussions and site visit it was established that it would be socially acceptable to design a secondary aid to navigation that would complement the primary aids of long cane or guide dog. A concept experiment was carried out to test the idea that knowledge about changes in surface colour could help with navigation. A prototype device that could be used by individuals with visual impairment to increase their confidence when navigating a difficult environment was designed, built and tested. Different programming methods were researched and trialled to effectively use machine vision to provide a solution to analyse video feed from a passive camera and return useful information to a blind or partially sighted user. The device was tested indoors and outdoors and found to be effective at detecting changes in surface colour. Further work is needed to run the software on a more compact platform such as a mobile phone, but initial results show that the concept is viable and that the barriers that present to blind and partially sighted people navigating difficult urban environments can be much reduced through the use of this technology

Proceedings of the 3rd IUI Workshop on Interacting with Smart Objects

These are the Proceedings of the 3rd IUI Workshop on Interacting with Smart Objects. Objects that we use in our everyday life are expanding their restricted interaction capabilities and provide functionalities that go far beyond their original functionality. They feature computing capabilities and are thus able to capture information, process and store it and interact with their environments, turning them into smart objects