Tactile Arrays for Virtual Textures

This thesis describes the development of three new tactile stimulators for active touch, i.e. devices to deliver virtual touch stimuli to the fingertip in response to exploratory movements by the user. All three stimulators are designed to provide spatiotemporal patterns of mechanical input to the skin via an array of contactors, each under individual computer control. Drive mechanisms are based on piezoelectric bimorphs in a cantilever geometry. The first of these is a 25-contactor array (5 × 5 contactors at 2 mm spacing). It is a rugged design with a compact drive system and is capable of producing strong stimuli when running from low voltage supplies. Combined with a PC mouse, it can be used for active exploration tasks. Pilot studies were performed which demonstrated that subjects could successfully use the device for discrimination of line orientation, simple shape identification and line following tasks. A 24-contactor stimulator (6 × 4 contactors at 2 mm spacing) with improved bandwidth was then developed. This features control electronics designed to transmit arbitrary waveforms to each channel (generated on-the-fly, in real time) and software for rapid development of experiments. It is built around a graphics tablet, giving high precision position capability over a large 2D workspace. Experiments using two-component stimuli (components at 40 Hz and 320 Hz) indicate that spectral balance within active stimuli is discriminable independent of overall intensity, and that the spatial variation (texture) within the target is easier to detect at 320 Hz that at 40 Hz. The third system developed (again 6 × 4 contactors at 2 mm spacing) was a lightweight modular stimulator developed for fingertip and thumb grasping tasks; furthermore it was integrated with force-feedback on each digit and a complex graphical display, forming a multi-modal Virtual Reality device for the display of virtual textiles. It is capable of broadband stimulation with real-time generated outputs derived from a physical model of the fabric surface. In an evaluation study, virtual textiles generated from physical measurements of real textiles were ranked in categories reflecting key mechanical and textural properties. The results were compared with a similar study performed on the real fabrics from which the virtual textiles had been derived. There was good agreement between the ratings of the virtual textiles and the real textiles, indicating that the virtual textiles are a good representation of the real textiles and that the system is delivering appropriate cues to the user

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

Designing a New Tactile Display Technology and its Disability Interactions

People with visual impairments have a strong desire for a refreshable tactile interface that can provide immediate access to full page of Braille and tactile graphics. Regrettably, existing devices come at a considerable expense and remain out of reach for many. The exorbitant costs associated with current tactile displays stem from their intricate design and the multitude of components needed for their construction. This underscores the pressing need for technological innovation that can enhance tactile displays, making them more accessible and available to individuals with visual impairments. This research thesis delves into the development of a novel tactile display technology known as Tacilia. This technology's necessity and prerequisites are informed by in-depth qualitative engagements with students who have visual impairments, alongside a systematic analysis of the prevailing architectures underpinning existing tactile display technologies. The evolution of Tacilia unfolds through iterative processes encompassing conceptualisation, prototyping, and evaluation. With Tacilia, three distinct products and interactive experiences are explored, empowering individuals to manually draw tactile graphics, generate digitally designed media through printing, and display these creations on a dynamic pin array display. This innovation underscores Tacilia's capability to streamline the creation of refreshable tactile displays, rendering them more fitting, usable, and economically viable for people with visual impairments

Expressing Tacit Material Sensations from a Robo-Sculpting Process by Communicating Shared Haptic Experiences

A sculptor's sense of touch is paramount because we experience sculpting in the iterative process of making new objects. Making sculpture is a process of expressing the inner 'tacit-self' by way of tangible material interactions that become shared artefacts. The existence of tacit- tactile awareness indicates a natural world of personal haptic experience that this thesis will attempt to unpack. Tele-haptic solutions are presented in the form of two robotic sculptures, Touchbot #1 and Touchbot #2. Touchbots (collectively) are the study objects that this practice- based art-research thesis produced, to ask the question: Is it possible to create a machine that could capture and retransmit tacit-tactile experiences within the artistic act of sculpting, through material engagement, from a sculptor's hand to a non-sculptor's hand? Research, conducted and presented, aims to demonstrate that robotic haptic feedback is a vehicle for communicating 'touch' messages through mechanical transmission during sculptural actions (demonstrated through participant interviews and video observation analysis). Additionally, an epistemological context for exploring 'hands-on' knowledge and practice deficits in machine-assisted object modelling is presented including: Michael Polanyi's Tacit Dimension (Polanyi, 2009), David Gooding's Thing Knowledge (Gooding, 2004, p. 1) and Lambros Malafouris' "Material Agency" and material culture (Malafouris, 2008, pp. 19-36). Intersecting bodies of knowledge weave a common thread to support developing a method of communicating tacit sculptural information using haptic touch experience. Unfortunately, there exists more tele-haptics and telerobotics technology for industrial applications than artworks using the same technology. For instance, 'rapid prototyping' technology—such as 3D printers—is removing human tactile-material interaction from object making altogether. In response to the technological obstacle of expanding contemporary interactive sculpture, haptics is applied to include real-time, iterative, robotically assisted object modelling. A review of contemporary haptic technology demonstrates a gap in our understanding iii of embodied knowledge transference. A shortlist of contemporary artists and their works that address the communication of tacit-haptic experiences is also offered, highlighting the importance of exploring embodied knowledge transfer

Expressing Tacit Material Sensations from a Robo-Sculpting Process by Communicating Shared Haptic Experiences

A sculptor's sense of touch is paramount because we experience sculpting in the iterative process of making new objects. Making sculpture is a process of expressing the inner 'tacit-self' by way of tangible material interactions that become shared artefacts. The existence of tacit- tactile awareness indicates a natural world of personal haptic experience that this thesis will attempt to unpack. Tele-haptic solutions are presented in the form of two robotic sculptures, Touchbot #1 and Touchbot #2. Touchbots (collectively) are the study objects that this practice- based art-research thesis produced, to ask the question: Is it possible to create a machine that could capture and retransmit tacit-tactile experiences within the artistic act of sculpting, through material engagement, from a sculptor's hand to a non-sculptor's hand? Research, conducted and presented, aims to demonstrate that robotic haptic feedback is a vehicle for communicating 'touch' messages through mechanical transmission during sculptural actions (demonstrated through participant interviews and video observation analysis). Additionally, an epistemological context for exploring 'hands-on' knowledge and practice deficits in machine-assisted object modelling is presented including: Michael Polanyi's Tacit Dimension (Polanyi, 2009), David Gooding's Thing Knowledge (Gooding, 2004, p. 1) and Lambros Malafouris' "Material Agency" and material culture (Malafouris, 2008, pp. 19-36). Intersecting bodies of knowledge weave a common thread to support developing a method of communicating tacit sculptural information using haptic touch experience. Unfortunately, there exists more tele-haptics and telerobotics technology for industrial applications than artworks using the same technology. For instance, 'rapid prototyping' technology—such as 3D printers—is removing human tactile-material interaction from object making altogether. In response to the technological obstacle of expanding contemporary interactive sculpture, haptics is applied to include real-time, iterative, robotically assisted object modelling. A review of contemporary haptic technology demonstrates a gap in our understanding iii of embodied knowledge transference. A shortlist of contemporary artists and their works that address the communication of tacit-haptic experiences is also offered, highlighting the importance of exploring embodied knowledge transfer

The Hand-Held Force Magnifier: Surgical Tools to Augment the Sense of Touch

Modern surgeons routinely perform procedures with noisy, sub-threshold, or obscured visual and haptic feedback,either due to the necessary approach, or because the systems on which they are operating are exceeding delicate. For example, in cataract extraction, ophthalmic surgeons must peel away thin membranes in order to access and replace the lens of the eye. Elsewhere, dissection is now commonly performed with energy-delivering tools – rather than sharp blades – and damage to deep structures is possible if tissue contact is not well controlled. Surgeons compensate for their lack of tactile sensibility by relying solely on visual feedback, observing tissue deformation and other visual cues through surgical microscopes or cameras. Using visual information alone can make a procedure more difficult, because cognitive mediation is required to convert visual feedback into motor action. We call this the “haptic problem” in surgery because the human sensorimotor loop is deprived of critical tactile afferent information, increasing the chance for intraoperative injury and requiring extensive training before clinicians reach independent proficiency. Tools that enhance the surgeon’s direct perception of tool-tissue forces can therefore potentially reduce the risk of iatrogenic complications and improve patient outcomes. Towards this end, we have developed and characterized a new robotic surgical tool, the Hand-Held Force Magnifier (HHFM), which amplifies forces at the tool tip so they may be readily perceived by the user, a paradigm we call “in-situ” force feedback. In this dissertation, we describe the development of successive generations of HHFM prototypes, and the evaluation of a proposed human-in-the-loop control framework using the methods of psychophysics. Using these techniques, we have verified that our tool can reduce sensory perception thresholds, augmenting the user’s abilities beyond what is normally possible. Further, we have created models of human motor control in surgically relevant tasks such as membrane puncture, which have shown to be sensitive to push-pull direction and handedness effects. Force augmentation has also demonstrated improvements to force control in isometric force generation tasks. Finally, in support of future psychophysics work, we have developed an inexpensive, high-bandwidth, single axis haptic renderer using a commercial audio speaker

Modelling, Simulation and Data Analysis in Acoustical Problems

Modelling and simulation in acoustics is currently gaining importance. In fact, with the development and improvement of innovative computational techniques and with the growing need for predictive models, an impressive boost has been observed in several research and application areas, such as noise control, indoor acoustics, and industrial applications. This led us to the proposal of a special issue about “Modelling, Simulation and Data Analysis in Acoustical Problems”, as we believe in the importance of these topics in modern acoustics’ studies. In total, 81 papers were submitted and 33 of them were published, with an acceptance rate of 37.5%. According to the number of papers submitted, it can be affirmed that this is a trending topic in the scientific and academic community and this special issue will try to provide a future reference for the research that will be developed in coming years

Haptic Interface for the Simulation of Endovascular Interventions

Endovascular interventions are minimally invasive surgical procedures that are performed to diagnose and treat vascular diseases. These interventions use a combination of long and flexible instruments known as guidewire and catheter. A popular method of developing the skills required to manipulate the instruments successfully is through the use of virtual reality (VR) simulators. However, the interfaces of current VR simulators have several shortcomings due to limitations in the instrument tracking and haptic feedback systems design. A major challenge of developing physics-based training simulations of endovascular interventional procedures is to unobtrusively access the central, co-axial guidewire for tracking and haptics. This work sets out to explore the state of the art, to identify and develop novel solutions to this concentric occlusion problem, and to perform a validation of a proof of concept prototype. This multi port haptic interface prototype has been integrated with a 3-D virtual environment and features novel instrument tracking and haptic feedback actuation systems. The former involves the use of an optical sensor to detect guidewire movements through a clear catheter, whereas the latter utilises the placement of a customised electromagnetic actuator within the catheter hub. During the proof of concept validation process, both systems received positive reviews. Whilst the haptic interface prototype designed in this work has met the original objectives, there are still important aspects which need to be addressed to improve its content and face validity. With further development, the prototype has the potential to evolve and become a significant improvement over the haptic interfaces that exist today.Open Acces