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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Development tool for push-buttons inside truck cabin

Björertz, Mikael January 2005 (has links)
<p>When developing the driver interface in their trucks, Scania is highly concerned with creating a certain feeling. When pressing a push-button this Scania feeling shall be perceived. It is not obvious what the Scania feeling really is and there is no predefined method to create it. This Master Thesis takes aim at providing the means to improve the process of creating this feeling.</p><p>First, the Scania feeling was studied via the results of an already made survey at Scania. This survey focused on subjective properties of push-buttons, rotary knobs and levers and related the properties to whether these objects had a Scania feeling or not. This existing data was analyzed statistically. The main task of this Master Thesis, however, was to create an environment where the feeling of a push-button could be tried out and described. This environment was created with a tool from Reachin Technologies AB. The environment is a virtual representation of a push-button module, created with computer haptics and graphics. The environment lets the user interact with a three dimensional view collocated with a force feedback device. The force feedback device lets the user feel what is seen through a pen like interface. The “tip” of the pen is used to touch what is seen in the 3D view. The virtual push-buttons was built from blueprints of real push-buttons to be able to evaluate to what extent the virtual buttons resembled the real ones.</p><p>The statistical analysis made in this project does not support the notion of describing the Scania feeling with a set of subjective values. The virtual environment created proved to be very life like. The real push-button feeling could be recreated with high precision. When evaluated, the majority of test persons argued that it could be used in the development process.</p>
32

Development tool for push-buttons inside truck cabin

Björertz, Mikael January 2005 (has links)
When developing the driver interface in their trucks, Scania is highly concerned with creating a certain feeling. When pressing a push-button this Scania feeling shall be perceived. It is not obvious what the Scania feeling really is and there is no predefined method to create it. This Master Thesis takes aim at providing the means to improve the process of creating this feeling. First, the Scania feeling was studied via the results of an already made survey at Scania. This survey focused on subjective properties of push-buttons, rotary knobs and levers and related the properties to whether these objects had a Scania feeling or not. This existing data was analyzed statistically. The main task of this Master Thesis, however, was to create an environment where the feeling of a push-button could be tried out and described. This environment was created with a tool from Reachin Technologies AB. The environment is a virtual representation of a push-button module, created with computer haptics and graphics. The environment lets the user interact with a three dimensional view collocated with a force feedback device. The force feedback device lets the user feel what is seen through a pen like interface. The “tip” of the pen is used to touch what is seen in the 3D view. The virtual push-buttons was built from blueprints of real push-buttons to be able to evaluate to what extent the virtual buttons resembled the real ones. The statistical analysis made in this project does not support the notion of describing the Scania feeling with a set of subjective values. The virtual environment created proved to be very life like. The real push-button feeling could be recreated with high precision. When evaluated, the majority of test persons argued that it could be used in the development process.
33

A Haptic Simulator for Gastrointestinal Endoscopy : Design Development and Experiments

Chakravarthy, Shanthanu January 2015 (has links) (PDF)
Endoscopy is an involved clinical practice requiring considerable skill in performing the procedure. Virtual reality together with haptics offers immersive, flexible, and cost-effective platform for training in endoscopic procedures. In this thesis, we present mechanical design, control, characterization, and integration of a novel endoscopic haptic simulator with three degrees of freedom. Related ideas, computations, and experiments that support endoscopy and endoscopic simulator are also investigated in this thesis. The haptic device is designed to reflect forces in the three important directions, namely, longitudinal, rotational, and radial directions. The mechanical design of the haptic device overcomes some of the limitations of the existing systems. The device provides large sustained output force and possesses low friction, low inertia and zero backlash. Dynamics-based feed-forward control algorithm is developed to achieve high fidelity and transparency in force-feedback. Tracking performance, transparency, and nonlinearity are all quantified using experiments designed to validate the control structure and to characterize the developed haptic device. The device is shown to apply a maximum continuous force of 11 N in the longitudinal direction, maximum continuous torque of 196 mN.m in the rotational DoF, and a maximum force of 1.5 N (at each of the four radial pads) in the radial direction. Furthermore, we also present the design of a novel compliant mechanism for the radial DoF. The circumferentially actuated compliant (CAC) mechanism is a planar, reversible, and single degree-of-freedom compliant mechanism that emulates controlled and responsive circularly shaped opening. The mechanism is designed in view of the anatomy of the throat and the special manoeuvre required for intubation of the endoscope into the oesophagus by avoiding the trachea. As part of the auxiliary work for the endoscopic simulator, we developed a computational technique for simulating the shape of the entire endoscope during endoscopy. Strain measurements made at discrete locations along the length of endoscope are used in the method. Strain measurement, stain interpolation, and shape reconstruction based on strain information are discussed. Furthermore, a method to predict the location of point forces acting on the endoscope tube during endoscopy is proposed. A novel concept of haptic playback for endoscopy is also investigated in this work. Haptic playback aids the endoscopists to recall both visual as well as haptic information from an earlier endoscopic session. The endoscopic playback concept is evaluated using psychophysical experiments. Through these experiments, we quantified haptic perception through the endoscope, the effect of temporal separation on haptic memory, and the interaction between haptic and visual information in sensory processing.
34

Networked Haptics

Olofsson, Martin, Öhman, Sebastian January 2009 (has links)
Haptic feedback is feedback relating to the sense of touch. Current research suggests that the use of haptic feedback could give an increase in speed and accuracy when doing certain tasks such as outlining organ contours in medical applications or even filling in spreadsheets. This master thesis project has two different goals concerning haptic feedback. The first is to try to improve the forces for the SensAble PHANTOM Omni® Haptic Device when used in an application to outline contours in medical images, to give the user better feedback. The PHANTOM Omni is a device able to read in user movement of an arm attached to it in three dimensions, but it is also able to output forces through this arm back to the user, i.e. giving haptic feedback. By improving these forces and thus providing better feedback, we hope that speed and accuracy increases for a user working with the mentioned application. The second part of the project consists of evaluating if delays in a network between the haptic feedback device and the place where the data sets are located impact the user perceived quality or the outcome of the task. We do this by considering a number of potential architectures for distributing the image processing and generation of haptic feedback. By considering both of these goals we hope to demonstrate both a way to get faster and more accurate results when doing the tasks already mentioned (and other tasks), but also to understand the limitations of haptic performance with regard to distributed processing. We have successfully fulfilled our first goal by introducing a haptic force which seems quite promising. This should mean that the people working with outlining contours in medical images can work more effectively; which is good both economically for hospitals and quality of service-wise for patients. Our results concerning the second goal indicate that a haptic system for outlining contour can work well when using this new haptic force, even on low quality data links (which can be used for example in battlefield medicine or by specialists to conduct long distance operations or examinations) -- if the system architecture distributes the functionality so as to provide low delay haptic feedback locally. We have tried to compare our results from the second part with a model for the impact of network delay on voice traffic quality developed by Cole and Rosenbluth, but as there is not necessarily a numeric correspondence between the quality values that we used and the ITU MOS quality values for voice we cannot make a numeric comparison between our results and that model. However our experimental data seem to suggest that the decrease in perceived quality was not as fast as one might expect considering simply the ratios of the voice packet rate (typically 50 Hz) and the 1000 Hz rate of the haptic feedback loop. The decrease in quality seems to only be about one half of what the ratio of these rates might suggest (i.e., a factor of 10x faster decrease in quality with increasing delay rather than 20x). / Haptisk återkoppling är återkoppling som fås genom känseln. Nutida forskning visar att användandet av sådan återkoppling kan öka effektiviteten vid vissa arbetsuppgifter inom sjukvård, till exempel vid förberedande uppgifter inom strålbehandling, men också vid kontorsarbete såsom att fylla i värden i ett kalkylark. Detta examensarbete har två mål som rör haptisk återkoppling. Det första är att försöka förbättra krafterna som ges från den haptiska enheten SensAble PHANTOM Omni® Haptic Device vid användning i ett medicinskt datorprogram rörande strålbehandling, i syfte att förbättra användareffektiviteten. PHANTOM Omni är en maskin som har en arm kopplad till sig som både kan läsa av rörelser och ge ut krafter med hjälp av en inbyggd motor, det vill säga ge haptisk återkoppling. Genom att förbättra dessa krafter och därigenom ge mer realistisk återkoppling hoppas vi att effektiviteten kan öka för en användare av det nämnda datorprogrammet. Det andra målet är att utvärdera hur fördröjningar i ett nätverk mellan den plats där enheten är placerad och den plats där informationen som ska bearbetas finns, påverkar upplevelsen för användaren och därmed resultatet av arbetet. Vi genomför detta genom att analysera flera olika tänkbara arkitekturer, där placeringen av bilddatat och uträkningen av krafter som ska ges ut av den haptiska enheten varierar. Genom att undersöka dessa två olika aspekter hoppas vi att vi både kan visa ett sätt att få snabbare och bättre resultat när man arbetar med uppgifter av den karaktären som redan beskrivits, men också att förstå begränsningarna för att använda haptisk återkoppling i distribuerade system. Vi har framgångsrikt lyckats uppfylla vårt första mål genom att utveckla en kraft till den haptiska enheten som verkar lovande. Om denna kraft funkar i praktiken innebär det att personer som arbetar med förberedande uppgifter inom strålbehandling kan göra dessa uppgifter effektivare vilket är positivt både ekonomiskt för sjukhusen och kvalitetsmässigt för patienterna. De resultat vi har fått fram avseende vårt andra mål indikerar att användandet av en haptisk enhet inom medicinsk bildbehandling kan fungera bra med vår nyutvecklade kraft, även på nätverkslänkar med dålig kvalitet (som kan vara fallet exempelvis när medicinska specialister utför undersökningar eller operationer på distans) – om systemet är uppbyggt så att den haptiska återkopplingen sker lokalt med en minimal fördröjning. Vi har försökt att jämföra våra resultat från nätverksdelen med en modell beskriven av Cole och Rosenbluth, som ger kvaliteten på rösttrafik som en funktion av fördröjningen i ett nätverk. Dock finns det inte nödvändigtvis någon korrelation mellan de värden vi har fått fram och den kvalitetsskala för rösttrafik som de använde. Vi kan därmed inte göra en jämförelse rakt av mellan våra resultat och deras modell. Däremot så pekar de data vi har fått i våra experiment på att den användarupplevda kvaliteten inte sänktes lika snabbt som man kunde ha väntat sig om man bara tar hänsyn till förhållandet mellan uppdateringsfrekvenserna för rösttrafik (vanligtvis 50 Hz) och den haptiska återkopplingen (1000 Hz). Kvalitetssänkningen verkar vara hälften av vad detta förhållande skulle kunna antyda (det vill säga en faktor på 10 gånger snabbare sänkning i kvalitet med ökande fördröjning snarare än 20 gånger).
35

Implamention and Evaluation of a Haptic Playback System for the Virtual Haptic Back

Srivastava, Mayank January 2005 (has links)
No description available.
36

Preparing Spatial Haptics for Interaction Design / Att förbereda 3D-Haptik för interaktionsdesign

Forsslund, Jonas January 2016 (has links)
Spatial haptics is a fascinating technology with which users can explore and modify3D computer graphics objects with the sense of touch, but its application potentialis often misunderstood. For a large group of application designers it is still unknown,and those who are aware of it often have either too high expectations of what is technicallyachievable or believe it is too complicated to consider at all. In addition, spatialhaptics is in its current form ill-suited to interaction design. This is partly because theproperties and use qualities cannot be experienced in an application prototype until asystem is fully implemented, which takes too much effort to be practical in most designsettings. In order to find a good match between a solution and a framing of aproblem, the designer needs to be able to mould/shape/form the technology into a solution,but also to re-frame the problem and question initial conceptual designs as shelearns more about what the technology affords. Both of these activities require a goodunderstanding of the design opportunities of this technology. In this thesis I present a new way of working with spatial haptic interaction design.Studying the serially linked mechanism from a well-known haptic device, and a forcereflectingcarving algorithm in particular, I show how to turn these technologies froman esoteric engineering form into a form ready for interaction design. The work isgrounded in a real application: an oral surgery simulator named Kobra that has beendeveloped over the course of seven years within our research group. Its design hasgone through an evolutionary process with iterative design and hundreds of encounterswith the audience; surgeon-teachers as users and potential customers. Some ideas, e.g.gestalting authentic patient cases, have as a result received increased attention by thedesign team, while other ideas, e.g. automatic assessment, have faded away. Simulation is an idea that leads to ideals of realism; that e.g. simulated instrumentsshould behave as in reality, e.g. a simulated dental instrument for prying teeth is expectedto behave according to the laws of physics and give force and torque feedback.If it does not, it is a bad simulation. In the present work it is shown how some of therealism ideal is unnecessary for creating meaningful learning applications and can actuallyeven be counter-productive, since it may limit the exploration of creative designsolutions. This result is a shift in perspective from working towards constantly improvingtechnological components, to finding and making use of the qualities of modern,but not necessarily absolute cutting-edge, haptic technology. To be able to work creatively with a haptic system as a design resource we needto learn its material qualities and how - through changing essential properties - meaningfulexperiential qualities can be modulated and tuned. This requires novel tools andworkflows that enable designers to explore the creative design space, create interactionsketches and tune the design to cater for the user experience. In essence, this thesisshows how one instance of spatial haptics can be turned from an esoteric technologyinto a design material, and how that can be used, and formed, with novel tools throughthe interaction design of a purposeful product in the domain of dental education. / 3D-haptik är en fascinerande teknologi med vilken användare kan utforska ochmodifiera tredimensionella datorgrafik-objekt med känseln, men dess användningspotentialär ofta missförstådd. För flertalet applikationsutvecklare är tekniken fortfarandetill stor del okänd, och de som känner till den har antingen alltför höga förväntingarav vad som är tekniskt möjligt, eller uppfattar 3D-haptik som alltför komplicerat föratt vara ett gångbart alternativ. Dessutom är 3D-haptik i sin nuvarande form tämligenomoget för interaktionsdesign. Detta beror till stor del på att en applikationsprototypsegenskaper och användarkvaliteter inte kan upplevas innan ett system är implementerati sin helhet, vilket kräver alltför stora utvecklingsresurser för att vara praktisktförsvarbart i de flesta designsituationer. För att uppnå en bra matchning mellan ett användarbehovi en viss situation och en potentiell lösning behöver en designer kunna åena sidan formge och finjustera tekniken, och å andra sidan vara öppen för att ifrågasättaoch ändra problemformulering och konceptdesign när hen lär sig mer om vilkamöjligheter tekniken erbjuder. Båda dessa aktiviteter kräver en god förståelse för vilkadesignmöjligheter som en viss teknik, eller material, erbjuder. I den här avhandlingen presenterar jag ett nytt sätt att arbeta med interaktionsdesignför 3D-haptik. Genom att studera i synnerhet den seriellt länkade mekanismen somåterfinns i en vanligt förekommande typ av 3D-haptikenhet, och en kraftåterkopplandeskärande/borrande algoritm visar jag hur man kan omvandla dessa teknologier från attvara en svårtillgänglig ingengörskonst till en form som är mer redo för interaktionsdesign.Denna förberedelse resulterar i ett slags designmaterial, samt de verktyg ochprocesser som har visat sig nödvändiga för att effektivt kunna arbeta med materialet.Forskningen är grundad i en verklig tillämpning: en simulator för käkkirurgi vidnamn Kobra, som har utvecklas under sju år inom vår forskargrupp. Kobras utformninghar genomgått en evolutionär utvecklingsprocess med iterativ design och hundratalsmöten med målgruppen; lärarpraktiserande käkkirurger och studenter som användareoch potentiella kunder. Därvid har några designidéer, t.ex. gestaltning av patientfall, avdesignteamet fått utökad uppmärksamhet medan andra idéer, t.ex. automatisk gradering,har tonats ned. Simulering är i sig självt en idé som ofta leder till ett ideal av realism; till exempelatt simulerade instrument ska uppföra sig som i verkligheten, det vill säga ett simulerattandläkarinstrument för att hävla (bända) tänder förväntas följa fysikens lagar och geåterkoppling i form av av både kraft och vridmoment. Om detta inte uppfylls betraktassimuleringen som undermålig. I det aktuella arbetet visas hur delar av realism-idealetinte är nödvändigt för att skapa meningsfulla lärandeapplikationer, och att det till ochmed kan vara kontraproduktivt eftersom det begränsar utforskande av kreativa designlösningar.Ifrågasättandet av realsimidealet resulterar i ett perspektivskifte vad gällersimulatorutveckling generellt, från att ensidigt fokusera på vidareutveckling av enskildatekniska komponenter, till att identifiera och dra nytta av kvaliteterna som redanerbjuds i modern haptisk teknik. För att kunna arbeta kreativt med ett haptiksystem som en designresurs behöver vilära känna dess materialkvaliteter och hur, genom att ändra grundläggande parametrar,meningsfulla upplevelsekvaliteter kan moduleras och finjusteras. Detta kräver i sin turnyskapande av verktyg och arbetsflöden som möjliggör utforskande av det kreativadesignrummet, skapande av interaktionssketcher och finjustering av gestaltningen föratt tillgodose användarupplevelsen. I grund och botten visar denna avhandling hur en specifik 3D-haptik-teknologi kanomvandlas från att vara en svårtillgänglig teknologi till att vara ett designmaterial, ochhur det kan användas, och formas, med nyskapande verktyg genom interaktionsdesignav en nyttoprodukt inom tandläkarutbildning / <p>QC 20160309</p>
37

Development of a Multiple Contact Haptic Display with Texture-Enhanced Graphics

Burch, David 10 May 2012 (has links)
This dissertation presents work towards the development of a multiple finger, worn, dynamic display device, which utilizes a method of texture encoded information to haptically render graphical images for individuals who are blind or visually impaired. The device interacts directly with the computer screen, using the colors and patterns displayed by the image as a means to encode complex patterns of vibrotactile output, generating the texture feedback to render the image. In turn, the texture feedback was methodically designed to enable parallel processing of certain coarse information, speeding up the exploration of the diagram and improving user performance. The design choices were validated when individuals who are blind or visually impaired, using the multi-fingered display system, performed three-times better using textured image representations versus outline representations. Furthermore, in an open-ended object identification task, the display device saw on average two-times better performance accuracy than that previously observed for raised-line diagrams, the current standard for tactile diagrams.
38

Development of an Inexpensive, Haptic Graphical Display Device

Burch, David 09 December 2008 (has links)
A finger-worn haptic device capable of rendering 2-D graphics through vibrotactile feedback is presented. The device development is presented from its initial stages of being a stylus design using a photo-interrupter optical sensor and pager-motor actuator to a small case worn on the finger using a RGB color sensor and a piezoelectric actuator. Testing of the latest prototype design shows that it has a spatial sensitivity (<2mm) comparable to natural touch (~1mm) and can be used to output a variety of vibrotactile textures. The design can be expanded for a multiple finger, independent device, while remaining affordable (<$100) and highly portable (<500g).
39

Multimodal Bioinspired Artificial Skin Module for Tactile Sensing

Alves de Oliveira, Thiago Eustaquio 30 January 2019 (has links)
Tactile sensors are the last frontier to robots that can handle everyday objects and interact with humans through contact. Robots are expected to recognize the properties of objects in order to handle them safely and efficiently in a variety of applications, such as health- and elder care, manufacturing, or high-risk environments. To be effective, such sensors have to sense the geometry of touched surfaces and objects, as well as any other relevant information for their tasks, such as forces, vibrations, and temperature, that allow them to safely and securely interact within an environment. Given the capability of humans to easily capture and interpret tactile data, one promising direction in order to produce enhanced robotic tactile sensors is to explore and imitate human tactile sensing capabilities. In this context, this thesis presents the design and hardware implementation issues related to the construction of a novel multimodal bio-inspired skin module for dynamic and static tactile surface characterization. Drawing inspiration from the type, functionality, and organization of cutaneous tactile elements in the human skin, the proposed solution determines the placement of two shallow sensors (a tactile array and a nine DOF magnetic, angular rate, and gravity system) and a deep pressure sensor within a flexible compliant structure, similar to the receptive field of the Pacinian mechanoreceptor. The benefit of using a compliant structure is tri-folded. First, the module has the capability of performing touch tasks on unknown surfaces, tackling the tactile inversion problem. The compliant structure guides deforming forces from its surface to the deep pressure sensor, while keeping track of the deformation of the structure using advantageously placed shallow sensors. Second, the module’s compliant structure and its embedded sensor placement provide useful data to overcome the problem of estimating non-normal forces, a significant challenge for the current generation of tactile sensing technologies. This capability allows accommodating sensing modalities essential for acquiring tactile images and classifying surfaces by vibrations and accelerations. Third, the compliant structure of the module also contributes to the relaxation of orientation constraints of end-effectors or other robotic parts carrying the module to contact surfaces of unknown objects. Issues related to the module calibration, its sensing capabilities and possible real-world applications are also presented.
40

Springback Force Considerations in Compliant Haptic Interfaces

Swiss, Dallin R 01 December 2015 (has links)
This thesis investigates the potential benefits and challenges of using compliant mechanisms in the design of haptic interfaces. The benefits and challenges are presented with an emphasis on their inherent springback behavior and an active compensation approach. Design criteria for compliant mechanism joint candidates are reviewed and several joints are surveyed. Quantitative calculations of axial stiffness and maximum stress for five candidates are presented. Generalized analytical models of springback force and compensation torque are created to simulate the implementation of each joint candidate in a two degree-of-freedom planar pantograph. We use these models in the development and discussion of an analytical approach to predict the motor torques needed to actively compensate for the effects of springback. This approach relies on virtual work analyses of the haptic pantograph to determine the springback forces, compensation torques, haptic workspace, and available haptic force after compensation. A key to estimating the available haptic force is knowing that the force capability is different depending on the local springback force. If a component of the desired haptic force aligns with the springback force, then the two can work together, thus increasing the maximum magnitude of available haptic force beyond the nominal amount. Analytical and experimental results are presented. A detailed method of implementation is given along with a hardware demonstration of active compensation.

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