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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.
101

Transparent Capacitive and Piezoelectric Micromachined Ultrasonic Transducers for Tactile Feedback with 3D Displays

Laughlin, Emily Anne 06 August 2021 (has links) (PDF)
3D display technology is limited by the user's ability to interact with displays without being connected to external equipment. In order to feel tactile feedback in conjunction with displays, ultrasonic sound pressure fields have been created; however, ceramic transducers interfere with the user's immersive experience. We have created transparent ultrasonic transducers using capacitive micromachined ultrasonic transducer (CMUT) and piezoelectric micromachined ultrasonic transducer (PMUT) technology that allow the user to remain immersed in the experience while interacting with the display. Individual transparent piezoelectric transducers made with indium tin oxide (ITO) and polyvinylidene fluoride (PVDF) generate 66.9dB with 91.6% transparency. Samples were phased and modulated using a field programmable gate array (FPGA) in a 36-element array.
102

New haptic syringe device for virtual angiography training

Huang, D., Tang, P., Wang, X., Wan, Tao Ruan, Tang, W. 01 April 2019 (has links)
No / Angiography is an important minimally invasive diagnostic procedure in endovascular interventions. Effective training for the procedure is expensive, time consuming and resource demanding. Realistic simulation has become a viable solution to addressing such challenges. However, much of previous work has been focused on software issues. In this paper, we present a novel hardware system-an interactive syringe device with haptics as an add-on hardware component to 3D VR angiography training simulator. Connected to a realistic 3D computer simulation environment, the hardware component provides injection haptic feedback effects for medical training. First, we present the design of corresponding novel electronic units consisting of many design modules. Second, we describe a curve fitting method to estimate injection dosage and injection speed of the contrast media based on voltage variation between the potentiometer to increase the realism of the simulated training. A stepper motor control method is developed to imitate the coronary pressure for force feedback of syringe. Experimental results show that the validity and feasibility of the new haptic syringe device for achieving good diffusion effects of contrast media in the simulation system. A user study experiment with medical doctors to assess the efficacy and realism of proposed simulator shows good outcomes. / National Natural Science Foundation of China (61402278), the Innovation Program of the Science and Technology Commission of Shanghai Municipality of China (16511101302), Research Program of Shanghai Engineering Research Center of Motion Picture Special Effects (16dz2251300)
103

The Effects of Direction and Magnitude of Optically Induced Proprioceptive Shift on Interlimb Rhythmic Coordination

Black, David P. 02 September 2003 (has links)
No description available.
104

HAPTIC HAPPENINGS: AN EXPLORATION OF SOUND, QUIET AND BLACKNESS

Redmon, Shanise January 2018 (has links)
This research analyzes the lives and works of Black visual artists and filmmakers as visual representations of haptic events. This thesis examines how the lives of the artists and specific works of art are entangled with sound and quiet and directly reflect and shape the complexities black interiority. The possibilities of the black interior expand when the senses are combined and how the utilization of that synthesis centers the interior lives, ideas and art of black people. Centering the interior life creates space for the humanity of black people to be fully realized and explored without disruption both individually and collectively. Artists Jean-Michel Basquiat, David Hammons, Nick Cave and filmmakers Arthur Jafa and Kahlil Joseph’s work is used to illustrate how a haptic event is formed, how the haptic event effects both the artist and the audience and how the outcome of the haptic informs the present moment and often surpass the confines of language. This project extends the concept of Hapticality and the futurity of black interior life as a site of reflection, expression and resistance. / African American Studies
105

Haptic-Enabled Collaborative Virtual Environments for Skills Training

Moghimi, Saba 06 1900 (has links)
<p> Many manual tasks such as those in surgical applications require a high degree of motor skills that can only be gained through extensive training. This thesis is concerned with the design and control of collaborative training virtual environments with haptic feedback for skills training. The term "collaborative training" refers to a scheme in which the trainee and the trainer operate in a shared virtual environment. They collaboratively carry out the intended tasks using a shared "virtual tool". In order to enhance the trainee's motor skills, the conventional visual feedback will be augmented by force feedback providing the feel of the task environment as well as active guidance by the expert trainer.</p> <p> First, a set of psychophysics experiments are designed to investigate the usefulness of haptic-enabled collaborative virtual environments for motor skills training. Eighteen volunteers randomly divided between two training and control groups have participated in the experiments. The training group would undergo a number of collaborative training sessions with active help from the trainer whereas the control group would try the task on their own to achieve a set of stated goals. Each of the experiments is designed with specific performance objectives in mind, including trajectory tracking and task completion time. The results of the psychophysics experiments confirm that, when visual feedback is partially impaired, haptic-enabled collaborative training improves learning of a trajectory tracking task. In all the experimental scenarios tested, the results showed improvements in temporal response after receiving training.</p> <p> The second part of the thesis is devoted to the development of a general control framework for the coordination of the users in haptic-enabled collaborative virtual environments. The haptic interface control design is separated from the virtual environment simulation in order to provide more versatility in control strategies for both impedance and admittance-type virtual environments. Adaptive nonlinear controllers are proposed that establish desired linear-time-invariant and/or nonlinear static mappings amongst the users and the virtual task environment positions and forces. These controllers account for the nonlinear model of haptic devices and can handle uncertainties in the haptic devices, the users, and the virtual environment dynamics. First, the tracking behavior of the system is shown via a Lyapunov analysis. Then using a priori known bounds on user and environment parameters, the robust stability of the system is analyzed by employing the Nyquist envelops of interval plants and an off-axis circle criterion. The robust stability analysis provides bounds on the parameter of the linear and nonlinear mappings within which the stability of the system is guaranteed, for all possible system parameters with their a priori given bounds. Experiments carried out with two similar Quanser twin-pantograph haptic devices confirm the effectiveness of the proposed controllers in achieving the performance and stability objectives.</p> / Thesis / Master of Applied Science (MASc)
106

Model-based design of haptic devices

Aftab, Ahmad January 2012 (has links)
Efficient engineering design and development of high precision and reliable surgical simulators, like haptic devices for surgical training benefits from model-based and simulation driven design. The complexity of the design space, multi-domains, multicriteria requirements and multi-physics character of the behavior of such a product ask for a model based systematic approach for creating and validating compact and computationally efficient simulation models to be used for the design process.The research presented in this thesis describes a model-based design approach towards the design of haptic devices for simulation of surgical procedures, in case of hard tissues such as bone or teeth milling. The proposed approach is applied to a new haptic device based on TAU configuration.The main contributions of this thesis are: Development and verification of kinematic and dynamic models of the TAU haptic device. Multi-objective optimization (MOO) approach for optimum design of the TAU haptic device by optimizing kinematic performance indices, like workspace volume, kinematic isotropy and torque requirement of actuators.  A methodology for creating an analytical and compact model of the quasi-static stiffness of haptic devices, which considers the stiffness of; actuation system;flexible links and passive joints. / QC 20120611
107

Longing For Touch : An investigation of what draws us to tactile experiences.

Larsen, Laura Astrup January 2024 (has links)
“Longing for Touch” is an investigation of what makes us drawn to tactile interactions. With this project and essay I am focussing on the importance of our haptic sense and draw attention to the experiences we lack, in a world where our experiences are getting digitalized to a greater extent. I am investigating how phenomena such as pleasure and aesthetics are linked together and how they can be used to foster physical interaction. I have a fascination of how we as humans are drawn towards disgust, and I’m interested in the tension these contradicting feelings create. In this essay I present research, that shows disgust both revolts and attracts, and I go over why disgust is an effective tool to capture attention. In the studio, I’m transforming my findings from the research into physical objects. By focusing on aesthetics while playing with elements of disgust – I can create objects we are drawn to touch. / <p>Two images have been removed for copyright reasons. The source information for the images are kept - in order for reader to access the images on their own.</p>
108

Contextualizing Remote Touch for Affect Conveyance

Wang, Rongrong 06 December 2012 (has links)
Touch is an expressive and powerful modality in affect conveyance. A simple touch like a hug can elicit strong feelings of affection both in the touch initiator and recipient. Therefore delivering touch over a distance to a long-distance family member or significant other has been an appealing concept for both researchers and designers. However compared to the development of audio, video channels which allow the transmission of voice, facial expression and gesture, digitally mediated touch (Remote Touch) has not received much attention. We believe that this is partially due to the lack of understanding of the capabilities and communication possibilities that remote touch brings. This dissertation presents a review of relevant psychological and sociological literature of touch and proposes a model of immediacy of the touch channel for affect conveyance. We advance three hypotheses regarding the possibility of remote touch in immediate affect conveyance: presence, fidelity and context. We posit that remote touch with relatively low touch fidelity can convey meaningful immediate affect when it is accompanied by a contextualizing channel. To test the hypothesis, two sets of remote touch devices are designed and prototyped which allow users to send/receive a squeeze on the upper arm to/from others effectively. Three in-lab user studies are conducted to investigate the role of remote touch in affect conveyance. These studies showed clearly that remote touch, when contextualized, can influence the affective component in communication. Our results demonstrated that remote touch can afford a rich spectrum of meanings and affects. Three major categories of the usage are identified as positive affect touch which serves to convey affects such as affection, sympathy and sharing, comfort etc., playful touch which serves to lighten the conversations, and conversational touch which serves to regulate the dynamics in the discourse. Our interview results also provide insights of how people use this new channel in their communication. / Ph. D.
109

Usable Accessibility and Haptic User Interface Design Approach

Kim, Hyung Nam 06 May 2010 (has links)
Many people have visual impairment and make up a population that is increasing each year. Haptic technology is often used to assist members of this population by providing a way of understanding visual information. Although haptic technology is relatively new, it is widely applied across a variety of domains (research and industry). However, a great number of users are dissatisfied with their assistive technology applications. Unfortunately, such dissatisfaction is likely to cause abandonment of the technology devices. In particular, recent research shows that the adoption rate of haptic technology is low. Discontinuing the use of assistive technology devices ultimately results in a waste of time, money, freedom, and reduced function for individuals with disabilities. Of all the factors that lead to abandonment, the most significant is the failure to meet user needs. Whether existing design approaches properly reflect assistive technology user needs should be explored, especially for haptic technology. Existing design approaches have rarely considered the heterogeneous needs of users in the same disability category (i.e., visual disability). Most previous studies on assistive technology have been oriented towards those with total blindness as opposed to those with residual vision (also referred to as low vision). In addition, researchers have paid less attention to older adults with low vision in terms of individual differences in haptic user interface (HUI) needs. There is also some doubt about the applicability of existing design approaches in such design contexts as users with visual disabilities using haptic user interfaces. The aim of this research was to investigate individual differences in users' capabilities in the haptic modality and user needs in HUIs. Particularly, age-related and vision-related individual differences were explored. Another aim was to develop a more accessible design approach applicable to users with visual disabilities and HUIs. The magnitude estimation technique was employed to examine how participants (classified by vision and age) perceive the same objective stimulus, such as haptic perception, differently. Brain plasticity theory was primarily applied to modify the existing design approach, PICTIVE. The effectiveness of modified and original PICTIVE methods was investigated in terms of the frequency of statements, gestures, satisfaction, and time to complete a given design task. HUI user needs were elicited from participants and were analyzed to understand age-related and vision-related individual differences. It was found that the haptic perception of the same objective stimulus was not significantly different between younger and older participants with low vision. The two age groups' overall preferences for a set of HUI user needs were not significantly different. In addition, the haptic perception of the same objective stimulus was not significantly different between sighted participants and those with low vision. The two vision groups' overall preferences on a set of HUI user needs were not significantly different as well. The two design methods resulted in significantly different outcomes. First, participants in the modified PICTIVE method made a significantly higher number of statements. Second, participants in the modified PICTIVE method showed a significantly higher number of gestures. Third, participants in the modified PICTIVE method took significantly more time because they had more design ideas to deliver. Last, both groups were satisfied with a given design method. In short, the research outcomes contribute to the advancement of knowledge and understanding of more "usable" accessibility for users with visual impairment and a more "accessible" participatory design approach to nontraditional user interfaces (i.e., haptic user interfaces) for users with visual impairment. / Ph. D.
110

Multidimensional Warnings: Determining an Appropriate Stimulus for a Curve-Warning Device

Neurauter, Michael L. 15 October 2004 (has links)
An average of 42,000 fatalities occur on the United States of America's roads each year as a result of motor-vehicle crashes (National Highway Traffic Safety Administration, 2003). The dangers with respect to curves exist, from late notification of direction and speed, varying methods for determining advisory speeds, as well as driver unfamiliarity and/or over confidence. A curve-warning device, a device that notifies the driver of an upcoming curve and, possibly, conveys its vehicle-specific advisory speed and even direction, has the potential to drastically reduce the dangers of curve navigation. This study was performed as a proof of concept with regard to appropriate modalities and respective stimuli for a curve warning application. For this study, objective and subjective measurements were collected in a simulator environment to compare conditions comprised of multiple stimuli from the auditory (icon, tone, and speech), visual (Heads Down Display and Heads Up Display), and haptic (throttle push-back) modalities. The results of the study show that the speech stimulus was the most appropriate of the auditory stimuli for both objective and subjective measurements. Objectively, the HDD and HUD were comparable with respect to performance, although the participants tended to favor the HDD in their subjective ratings. The throttle push-back did little to positively impact the performance measurements, and based on participant comments and ratings, it is not recommended for a curve-warning application. Of the stimulus conditions (combinations of two and three modalities), the Speech and HDD condition provided performance gains and subjective acceptability above the rest of the conditions. / Master of Science

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