27 research outputs found

    Realistic Haptics Interaction in Complex Virtual Environments

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    New Geometric Data Structures for Collision Detection

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    We present new geometric data structures for collision detection and more, including: Inner Sphere Trees - the first data structure to compute the peneration volume efficiently. Protosphere - an new algorithm to compute space filling sphere packings for arbitrary objects. Kinetic AABBs - a bounding volume hierarchy that is optimal in the number of updates when the objects deform. Kinetic Separation-List - an algorithm that is able to perform continuous collision detection for complex deformable objects in real-time. Moreover, we present applications of these new approaches to hand animation, real-time collision avoidance in dynamic environments for robots and haptic rendering, including a user study that exploits the influence of the degrees of freedom in complex haptic interactions. Last but not least, we present a new benchmarking suite for both, peformance and quality benchmarks, and a theoretic analysis of the running-time of bounding volume-based collision detection algorithms

    Haptic Guidance for Teleoperation: Optimizing Performance and User Experience

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    Haptic guidance in teleoperation (e.g. of robotic systems) is a pioneering approach to successfully combine automation and human competencies. In the current user study, various forms of haptic guidance were evaluated in terms of user performance and experience. Twenty-six participants completed an obstacle avoidance task and a peg-in-hole task in a virtual environment using a seven DoF force feedback device. Three types of haptic guidance (translational, rotational, combination of both, i.e. 6 DoF) and three guidance forces and torques (stiffnesses) were compared. Moreover, a secondary task paradigm was utilized to explore the effects of additional cognitive load. The results show that haptic guidance significantly improves performance (i.e. completion times, collision forces). Best results were obtained when the guidance forces were set to a medium or high value. Additionally, feelings of control were significantly increased during higher cognitive load conditions when being supported by translational haptic guidance

    Haptics: Science, Technology, Applications

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    This open access book constitutes the proceedings of the 13th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2022, held in Hamburg, Germany, in May 2022. The 36 regular papers included in this book were carefully reviewed and selected from 129 submissions. They were organized in topical sections as follows: haptic science; haptic technology; and haptic applications

    6D Frictional Contact for Rigid Bodies

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    International audienceWe present a new approach to modeling contact between rigid objects that augments an individual Coulomb friction point-contact model with rolling and spinning friction constraints. Starting from the intersection volume, we compute a contact normal from the volume gradient. We compute a contact position from the first moment of the intersection volume, and approximate the extent of the contact patch from the second moment of the intersection volume. By incorporating knowledge of the contact patch into a point contact Coulomb friction formulation, we produce a 6D constraint that provides appropriate limits on torques to accommodate displacement of the center of pressure within the contact patch, while also providing a rotational torque due to dry friction to resist spinning. A collection of examples demonstrate the power and benefits of this simple formulation

    Improvement of a Multi-Body Collision Computation Framework and Its Application to Robot (Self-)Collision Avoidance

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    One of the fundamental demands on robotic systems is a safe interaction with their environment. In order to fulfill that condition, both collisions with obstacles and own structure have to be avoided. This problem has been addressed before at the German Aerospace Center (DLR) through the use of different algorithms. In this work, a novel solution that differentiates itself from previous implementations due to its geometry-independent, flexible thread structure and computationally robust nature is presented. In a first step, in order to achieve self-collision avoidance, collision detection must be handled. In this line, the Robotics and Mechatronics Center of the DLR developed its own version of the Voxmap-Pointshell (VPS) Algorithm. This penalty based collision computation algorithm uses two types of haptic data structures for each pair of potentially colliding objects in order to detect contact points and compute forces of interfering virtual objects; voxelmaps and pointshells. Prior to the work presented, a framework for multi-body collision detection already existed. However, it was not designed nor optimized to handle mechanisms. This thesis resents a framework that handles collision detection, force computation and physics processing of multi-body virtual realities in real-time integrating the DLR VPS Algorithm implementation. Due to the high number of available robots and mechanisms, a method that is both robust and generic enough to withstand the forthcoming developments would be desirable. In this work, an input configuration file detailing the mechanism’s structure is used, based on the Denavit-Hartenberg convention, so that any type of robotic system or virtual object can use this method without any loss of validity. Experiments to prove the validity of this work have been performed both on DLR’s HUG simulator and on DLR’s HUG haptic device, composed of two DLR-KUKA light weight robots (LWRs)

    Sensory Communication

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    Contains table of contents for Section 2, an introduction and reports on fourteen research projects.National Institutes of Health Grant RO1 DC00117National Institutes of Health Grant RO1 DC02032National Institutes of Health/National Institute on Deafness and Other Communication Disorders Grant R01 DC00126National Institutes of Health Grant R01 DC00270National Institutes of Health Contract N01 DC52107U.S. Navy - Office of Naval Research/Naval Air Warfare Center Contract N61339-95-K-0014U.S. Navy - Office of Naval Research/Naval Air Warfare Center Contract N61339-96-K-0003U.S. Navy - Office of Naval Research Grant N00014-96-1-0379U.S. Air Force - Office of Scientific Research Grant F49620-95-1-0176U.S. Air Force - Office of Scientific Research Grant F49620-96-1-0202U.S. Navy - Office of Naval Research Subcontract 40167U.S. Navy - Office of Naval Research/Naval Air Warfare Center Contract N61339-96-K-0002National Institutes of Health Grant R01-NS33778U.S. Navy - Office of Naval Research Grant N00014-92-J-184

    Realistic Interaction with Virtual Objects within Arm's Reach

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    The automotive industry requires realistic virtual reality applications more than other domains to increase the efficiency of product development. Currently, the visual quality of virtual invironments resembles reality, but interaction within these environments is usually far from what is known in everyday life. Several realistic research approaches exist, however they are still not all-encompassing enough to be usable in industrial processes. This thesis realizes lifelike direct multi-hand and multi-finger interaction with arbitrary objects, and proposes algorithmic and technical improvements that also approach lifelike usability. In addition, the thesis proposes methods to measure the effectiveness and usability of such interaction techniques as well as discusses different types of grasping feedback that support the user during interaction. Realistic and reliable interaction is reached through the combination of robust grasping heuristics and plausible pseudophysical object reactions. The easy-to-compute grasping rules use the objects’ surface normals, and mimic human grasping behavior. The novel concept of Normal Proxies increases grasping stability and diminishes challenges induced by adverse normals. The intricate act of picking-up thin and tiny objects remains challenging for some users. These cases are further supported by the consideration of finger pinches, which are measured with a specialized finger tracking device. With regard to typical object constraints, realistic object motion is geometrically calculated as a plausible reaction on user input. The resulting direct finger-based interaction technique enables realistic and intuitive manipulation of arbitrary objects. The thesis proposes two methods that prove and compare effectiveness and usability. An expert review indicates that experienced users quickly familiarize themselves with the technique. A quantitative and qualitative user study shows that direct finger-based interaction is preferred over indirect interaction in the context of functional car assessments. While controller-based interaction is more robust, the direct finger-based interaction provides greater realism, and becomes nearly as reliable when the pinch-sensitive mechanism is used. At present, the haptic channel is not used in industrial virtual reality applications. That is why it can be used for grasping feedback which improves the users’ understanding of the grasping situation. This thesis realizes a novel pressure-based tactile feedback at the fingertips. As an alternative, vibro-tactile feedback at the same location is realized as well as visual feedback by the coloring of grasp-involved finger segments. The feedback approaches are also compared within the user study, which reveals that grasping feedback is a requirement to judge grasp status and that tactile feedback improves interaction independent of the used display system. The considerably stronger vibrational tactile feedback can quickly become annoying during interaction. The interaction improvements and hardware enhancements make it possible to interact with virtual objects in a realistic and reliable manner. By addressing realism and reliability, this thesis paves the way for the virtual evaluation of human-object interaction, which is necessary for a broader application of virtual environments in the automotive industry and other domains.StĂ€rker als andere Branchen benötigt die Automobilindustrie realistische Virtual Reality Anwendungen fĂŒr eine effiziente Produktentwicklung. WĂ€hrend sich die visuelle QualitĂ€t virtueller Darstellungen bereits der RealitĂ€t angenĂ€hert hat, ist die Interaktion mit virtuellen Umgebungen noch weit vom tĂ€glichen Erleben der Menschen entfernt. Einige ForschungsansĂ€tze haben sich mit realistischer Interaktion befasst, gehen aber nicht weit genug, um in industriellen Prozessen eingesetzt zu werden. Diese Arbeit realisiert eine lebensnahe mehrhĂ€ndige und fingerbasierte Interaktion mit beliebigen Objekten. Dabei ermöglichen algorithmische und technische Verbesserungen eine realitĂ€tsnahe Usability. Außerdem werden Methoden fĂŒr die Evaluation dieser Interaktionstechnik vorgestellt und benutzerunterstĂŒtzende Greiffeedbackarten diskutiert. Die verlĂ€ssliche und gleichzeitig realistische Interaktion wird durch die Kombination von robusten Greifheuristiken und pseudophysikalischen Objektreaktionen erreicht. Die das menschliche Greifverhalten nachbildenden Greifregeln basieren auf den OberflĂ€chennormalen der Objekte. Die Reduktion negativer EinflĂŒsse verfĂ€lschter Normalen und eine höhere GriffstabilitĂ€t werden durch das neuartige Konzept der Normal Proxies erreicht. Dennoch bleibt fĂŒr manche Nutzer das Aufnehmen von dĂŒnnen und kleinen Objekten problematisch. Diese FĂ€lle werden zusĂ€tzlich durch die Einbeziehung von FingerberĂŒhrungen unterstĂŒtzt, die mit einem speziellen Fingertracking GerĂ€t erfasst werden. Plausible Objektreaktionen auf Benutzereingaben werden unter BerĂŒcksichtigung typischer ObjekteinschrĂ€nkungen geometrisch berechnet. Die Arbeit schlĂ€gt zwei Methoden zur Evaluierung der fingerbasierten Interaktion vor. Ein Expertenreview zeigt, dass sich erfahrene Benutzer sehr schnell in die Technik einfinden. In einer Benutzerstudie wird nachgewiesen, dass fingerbasierte Interaktion im hier untersuchten Kontext vor indirekter Interaktion mit einem EingabegerĂ€t bevorzugt wird. WĂ€hrend letztere robuster zu handhaben ist, stellt die fingerbasierte Interaktion einen deutlich höheren Realismus bereit und erreicht mit den vorgeschlagenen Verbesserungen eine vergleichbare VerlĂ€sslichkeit. Um Greifsituationen transparent zu gestalten, realisiert diese Arbeit ein neuartiges druckbasiertes taktiles Feedback an den Fingerspitzen. Alternativ wird ein vibrotaktiles Feedback am gleichen Ort realisiert und visuelles Feedback durch die EinfĂ€rbung der griffbeteiligten Fingersegmente umgesetzt. Die verschiedenen FeedbackansĂ€tze werden in der Benutzerstudie verglichen. Dabei wird Greiffeedback als Voraussetzung identifiziert, um den Greifzustand zu beurteilen. Taktiles Feedback verbessert dabei die Interaktion unabhĂ€ngig vom eingesetzten Display. Das merklich stĂ€rkere Vibrationsfeedback kann wĂ€hrend der Interaktion störend wirken. Die vorgestellten Interaktionsverbesserungen und Hardwareerweiterungen ermöglichen es, mit virtuellen Objekten auf realistische und zuverlĂ€ssige Art zu interagieren. Indem die Arbeit Realismus und VerlĂ€sslichkeit gleichzeitig adressiert, bereitet sie den Boden fĂŒr die virtuelle Untersuchung von Mensch-Objekt Interaktionen und ermöglicht so einen breiteren Einsatz virtueller Techniken in der Automobilindustrie und in anderen Bereichen

    Realistic Interaction with Virtual Objects within Arm's Reach

    Get PDF
    The automotive industry requires realistic virtual reality applications more than other domains to increase the efficiency of product development. Currently, the visual quality of virtual invironments resembles reality, but interaction within these environments is usually far from what is known in everyday life. Several realistic research approaches exist, however they are still not all-encompassing enough to be usable in industrial processes. This thesis realizes lifelike direct multi-hand and multi-finger interaction with arbitrary objects, and proposes algorithmic and technical improvements that also approach lifelike usability. In addition, the thesis proposes methods to measure the effectiveness and usability of such interaction techniques as well as discusses different types of grasping feedback that support the user during interaction. Realistic and reliable interaction is reached through the combination of robust grasping heuristics and plausible pseudophysical object reactions. The easy-to-compute grasping rules use the objects’ surface normals, and mimic human grasping behavior. The novel concept of Normal Proxies increases grasping stability and diminishes challenges induced by adverse normals. The intricate act of picking-up thin and tiny objects remains challenging for some users. These cases are further supported by the consideration of finger pinches, which are measured with a specialized finger tracking device. With regard to typical object constraints, realistic object motion is geometrically calculated as a plausible reaction on user input. The resulting direct finger-based interaction technique enables realistic and intuitive manipulation of arbitrary objects. The thesis proposes two methods that prove and compare effectiveness and usability. An expert review indicates that experienced users quickly familiarize themselves with the technique. A quantitative and qualitative user study shows that direct finger-based interaction is preferred over indirect interaction in the context of functional car assessments. While controller-based interaction is more robust, the direct finger-based interaction provides greater realism, and becomes nearly as reliable when the pinch-sensitive mechanism is used. At present, the haptic channel is not used in industrial virtual reality applications. That is why it can be used for grasping feedback which improves the users’ understanding of the grasping situation. This thesis realizes a novel pressure-based tactile feedback at the fingertips. As an alternative, vibro-tactile feedback at the same location is realized as well as visual feedback by the coloring of grasp-involved finger segments. The feedback approaches are also compared within the user study, which reveals that grasping feedback is a requirement to judge grasp status and that tactile feedback improves interaction independent of the used display system. The considerably stronger vibrational tactile feedback can quickly become annoying during interaction. The interaction improvements and hardware enhancements make it possible to interact with virtual objects in a realistic and reliable manner. By addressing realism and reliability, this thesis paves the way for the virtual evaluation of human-object interaction, which is necessary for a broader application of virtual environments in the automotive industry and other domains.StĂ€rker als andere Branchen benötigt die Automobilindustrie realistische Virtual Reality Anwendungen fĂŒr eine effiziente Produktentwicklung. WĂ€hrend sich die visuelle QualitĂ€t virtueller Darstellungen bereits der RealitĂ€t angenĂ€hert hat, ist die Interaktion mit virtuellen Umgebungen noch weit vom tĂ€glichen Erleben der Menschen entfernt. Einige ForschungsansĂ€tze haben sich mit realistischer Interaktion befasst, gehen aber nicht weit genug, um in industriellen Prozessen eingesetzt zu werden. Diese Arbeit realisiert eine lebensnahe mehrhĂ€ndige und fingerbasierte Interaktion mit beliebigen Objekten. Dabei ermöglichen algorithmische und technische Verbesserungen eine realitĂ€tsnahe Usability. Außerdem werden Methoden fĂŒr die Evaluation dieser Interaktionstechnik vorgestellt und benutzerunterstĂŒtzende Greiffeedbackarten diskutiert. Die verlĂ€ssliche und gleichzeitig realistische Interaktion wird durch die Kombination von robusten Greifheuristiken und pseudophysikalischen Objektreaktionen erreicht. Die das menschliche Greifverhalten nachbildenden Greifregeln basieren auf den OberflĂ€chennormalen der Objekte. Die Reduktion negativer EinflĂŒsse verfĂ€lschter Normalen und eine höhere GriffstabilitĂ€t werden durch das neuartige Konzept der Normal Proxies erreicht. Dennoch bleibt fĂŒr manche Nutzer das Aufnehmen von dĂŒnnen und kleinen Objekten problematisch. Diese FĂ€lle werden zusĂ€tzlich durch die Einbeziehung von FingerberĂŒhrungen unterstĂŒtzt, die mit einem speziellen Fingertracking GerĂ€t erfasst werden. Plausible Objektreaktionen auf Benutzereingaben werden unter BerĂŒcksichtigung typischer ObjekteinschrĂ€nkungen geometrisch berechnet. Die Arbeit schlĂ€gt zwei Methoden zur Evaluierung der fingerbasierten Interaktion vor. Ein Expertenreview zeigt, dass sich erfahrene Benutzer sehr schnell in die Technik einfinden. In einer Benutzerstudie wird nachgewiesen, dass fingerbasierte Interaktion im hier untersuchten Kontext vor indirekter Interaktion mit einem EingabegerĂ€t bevorzugt wird. WĂ€hrend letztere robuster zu handhaben ist, stellt die fingerbasierte Interaktion einen deutlich höheren Realismus bereit und erreicht mit den vorgeschlagenen Verbesserungen eine vergleichbare VerlĂ€sslichkeit. Um Greifsituationen transparent zu gestalten, realisiert diese Arbeit ein neuartiges druckbasiertes taktiles Feedback an den Fingerspitzen. Alternativ wird ein vibrotaktiles Feedback am gleichen Ort realisiert und visuelles Feedback durch die EinfĂ€rbung der griffbeteiligten Fingersegmente umgesetzt. Die verschiedenen FeedbackansĂ€tze werden in der Benutzerstudie verglichen. Dabei wird Greiffeedback als Voraussetzung identifiziert, um den Greifzustand zu beurteilen. Taktiles Feedback verbessert dabei die Interaktion unabhĂ€ngig vom eingesetzten Display. Das merklich stĂ€rkere Vibrationsfeedback kann wĂ€hrend der Interaktion störend wirken. Die vorgestellten Interaktionsverbesserungen und Hardwareerweiterungen ermöglichen es, mit virtuellen Objekten auf realistische und zuverlĂ€ssige Art zu interagieren. Indem die Arbeit Realismus und VerlĂ€sslichkeit gleichzeitig adressiert, bereitet sie den Boden fĂŒr die virtuelle Untersuchung von Mensch-Objekt Interaktionen und ermöglicht so einen breiteren Einsatz virtueller Techniken in der Automobilindustrie und in anderen Bereichen
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