Haptic Design Research Articles

An Examination of Ultrasound Mid-air Haptics for Enhanced Material and Temperature Perception in Virtual Environments

Rendering realistic tactile sensations of virtual objects remains a challenge in VR. While haptic interfaces have advanced, particularly with phased arrays, their ability to create realistic object properties like state and temperature remains unclear. This study investigates the potential of Ultrasound Mid-air Haptics (UMH) for enhancing the perceived congruency of virtual objects. In a user study with 30 participants, we assessed how UMH impacts the perceived material state and temperature of virtual objects. We also analyzed EEG data to understand how participants integrate UMH information physiologically. Our results reveal that UMH significantly enhances the perceived congruency of virtual objects, particularly for solid objects, reducing the feeling of mismatch between visual and tactile feedback. Additionally, UMH consistently increases the perceived temperature of virtual objects. These findings offer valuable insights for haptic designers, demonstrating UMH's potential for creating more immersive tactile experiences in VR by addressing key limitations in current haptic technologies.

Bridging Divide with Innovative Media: Telexistence and Human Augmentation

This paper explores the transformative potential of haptic design and human augmentation, inspired by Dr. Minamizawa's keynote address at the 2024 Emerging Media for Communicating Sustainable Development Goals conference (held in Yang Ming Chiao Tung University, 30 March, 2024). By integrating tactile feedback into prosthetics and wearable devices, and employing robotic avatars and virtual interfaces, these technologies bridge the physical and virtual realms, redefining presence and interaction. The convergence of haptic design with telexistence and human augmentation enhances sensory engagement and bodily awareness, challenging traditional boundaries between biology and technology. However, these advancements might also raise ethical considerations and societal concerns about privacy, accessibility, autonomy, and safety. The future of human augmentation demands responsible development and inclusive dialogue to ensure empowerment, equity, and collective progress. This paper highlights the need for a human-integration approach to navigate the opportunities and challenges presented by these emerging technologies.

Haptic tele-driving design of vehicle steering control system with communication delay under complicated driving and road conditions

Haptic tele-driving design of vehicle steering control system with communication delay under complicated driving and road conditions

CoTacs: A Haptic Toolkit to Explore Effective On-Body Haptic Feedback by Ideating, Designing, Evaluating and Refining Haptic Designs Using Group Collaboration

Designing effective haptic feedback is challenging due to the subjective nature of touch and the fact that multiple people cannot easily share and evaluate touch experiences. In this work, we propose CoTacs, a collaborative haptic toolkit to address the challenges of haptic feedback design by enabling designers to explore haptic experiences together using group collaboration and allowing them to refine ideas quickly through early feedback during the design process. Two design sessions with five collaborators each show that CoTacs enables users to design, evaluate, refine and explore haptic feedback together. Participants leveraged group feedback to improve their designs and inspire creative ideas for the second collaboration round. Our work demonstrates how collaborative haptic toolkits can enable synergistic effects through interactions between the designers, benefiting haptic feedback design while still exposing several limitations. We discuss different opportunities for the design of future collaborative haptic toolkits and haptic group collaboration techniques.

Rotational stability of toric intraocular lenses by lens model and haptic design: systematic review and single-arm meta-analysis.

Rotational stability is key for optimizing postoperative visual outcomes because even a small degree of rotation of a toric intraocular lens (IOL) from its target axis can result in a significant reduction in astigmatic correction. This systematic review and meta-analysis evaluated the rotational stability of toric IOLs of different lens models and haptic designs. All published studies and clinical trials that investigate postoperative rotation of toric IOLs were searched and evaluated. Quality of studies was assessed using the Methodological Index for Nonrandomized Studies scale. A single-arm meta-analysis was performed in R4.3.1 software with subgroup analysis performed based on lens model and haptic design. 51 published studies of 4863 eyes were included in the meta-analysis. The pooled mean absolute rotation of all toric IOLs was 2.36 degrees (95% CI, 2.08-2.64). Postoperative rotation is dependent on many aspects of lens material and design. Modern commercially available toric IOLs exhibit exceptional rotational stability.

The Impact of Affective Haptic Design of Wearable Devices on Persian Users

Evidence indicates haptic stimulation can effectively evoke emotions and can be utilized in communication technologies’ design. Due to the impact of culture on people’s tactile behaviours and lack of research in West Asian cultures, this study aims to investigate the impact of affective haptics in Persian users. Using a wearable prototype, a test is conducted on 78 users to evaluate the arousal and valence level of their 4 emotions (anger, happiness, relaxed and sadness) when exposed to text messages with and without haptic stimulation and to see if they can recognise the stimuli with given haptic patterns. A semi-focused interview is also done to evaluate the results further with qualitative feedbacks. Results show vibro-tactile stimuli increase the arousal level and reduce the valence level of the emotions; however, vibrotactile stimuli cannot convey the desired valence level as they cannot render the tactile patterns related to each emotion properly.

Evaluation of Point-to-Point Reaching Performance in Mixed Reality and Virtual Reality

Abstract Recent immersive mixed reality (MR) and virtual reality (VR) displays enable users to use their hands to interact with both veridical and virtual environments simultaneously. Therefore, it becomes important to understand the performance of human hand-reaching movement in MR. Studies have shown that different virtual environment visualization modalities can affect point-to-point reaching performance using a stylus, but it is not yet known if these effects translate to direct human-hand interactions in mixed reality. This paper focuses on evaluating human point-to-point motor performance in MR and VR for both finger-pointing and cup-placement tasks. Six performance measures relevant to haptic interface design were measured for both tasks under several different visualization conditions (“MR with indicator”, “MR without indicator”, and “VR”) to determine what factors contribute to hand-reaching performance. A key finding was evidence of a trade-off between reaching motion confidence” measures (indicated by throughput, number of corrective movements, and peak velocity) and “accuracy” measures (indicated by end-point error and initial movement error). Specifically, we observed that participants tended to be more confident in the “MR without Indicator” condition for finger-pointing tasks. These results contribute critical knowledge to inform the design of VR/MR interfaces based on the application's user performance requirements.

Rotational stability and capsular bag performance of a hydrophobic acrylic open-loop single-piece intraocular lens.

To evaluate the rotational stability and capsular bag performance of a blue light-absorbing hydrophobic acrylic open-loop single-piece intraocular lens (IOL) with a blast-finished anchor wing haptic design during the first 6 postoperative months. In this prospective clinical study, patients with age-related cataract and potential postoperative corrected distance visual acuity (CDVA) of 0.2 logMAR or better were included. The patients received a non-toric hydrophobic acrylic single-piece IOL with an axis mark (YST0.00; Nidek Co. Ltd, Japan). Surgeries were video-taped. Retroillumination images were acquired 1 h, 1 week and 6 months postoperatively. Rotational stability was assessed by precise image overlay. At 6 months, Purkinje meter measurements were performed to evaluate tilt and decentration. In total, 100 eyes of 77 patients were included in the analysis. Mean absolute rotation was 2.1 ± 1.7° (median 1.7, range: 0-7.9) at 6 months (1 h - 6 months postoperatively). IOL rotation was ≤3° and ≤6° in 74 (74%) and 98 (98%) eyes, respectively. Mean absolute IOL rotation from the end of surgery to 6 months was 2.5 ± 2.2° (median 2.3, range: 0-15.6; n = 78). Mean tilt (pupillary axis) and decentration were 4.1 ± 1.9° (median 4.0, range: 0.5-8.2) and 0.35 ± 0.17 mm (median 0.32, range: 0.06-0.91) respectively (n = 84). Postoperatively, 98 (98%) eyes achieved a CDVA of 0.2 logMAR or better, 95 (95%) of ≤0.1 and 81 (81%) of ≤0.0. This hydrophobic acrylic single-piece IOL showed an excellent rotational stability and capsular bag position with low tilt and decentration values.

RecHap: An Interactive Recommender System for Navigating a Large Number of Mid-Air Haptic Designs.

Designing haptics is a difficult task especially when the user attempts to design a sensation from scratch. In the fields of visual and audio design, designers often use a large library of examples for inspiration, supported by intelligent systems like recommender systems. In this work, we contribute a corpus of 10 000 mid-air haptic designs (500 hand-designed sensations augmented 20x to create 10 000), and we use it to investigate a novel method for both novice and experienced hapticians to use these examples in mid-air haptic design. The RecHap design tool uses a neural-network based recommendation system that suggests pre-existing examples by sampling various regions of an encoded latent space. The tool also provides a graphical user interface for designers to visualize the sensation in 3D view, select previous designs, and bookmark favourites, all while feeling designs in real-time. We conducted a user study with 12 participants suggesting that the tool enables people to quickly explore design ideas and experience them immediately. The design suggestions encouraged collaboration, expression, exploration, and enjoyment, which improved creativity support.

HapticPilot

The emergence of vibrotactile feedback in hand wearables enables immersive virtual reality (VR) experience with whole-hand haptic rendering. However, existing haptic rendering neglects inconsistent sensations caused by hand postures. In our study, we observed that changing hand postures alters the distribution of vibrotactile signals which might degrade one's haptic perception. To address the issues, we present HapticPilot which allows an in-situ haptic experience design for hand wearables in VR. We developed an in-situ authoring system supporting instant haptic design. In the authoring tool, we applied our posture-adaptive haptic rendering algorithm with a novel haptic design abstraction called phantom grid. The algorithm adapts phantom grid to the target posture and incorporates 1D & 2D phantom sensation with a unique actuator arrangement to provide a whole-hand experience. With this method, HapticPilot provides a consistent haptic experience across various hand postures is available. Through measuring perceptual haptic performance and collecting qualitative feedback, we validated the usability of the system. In the end, we demonstrated our system with prospective VR scenarios showing how it enables an intuitive, empowering, and responsive haptic authoring framework.

The Ludic Impact of Horror Games on the Body: Until Dawn, Amnesia: The Dark Descent, and Alien: Isolation

Abstract Horror video games create an enhanced sense of fear compared to film and television of the same genre due to their use of ludic elements. These ludic elements, specifically haptic game design mechanics, play conditioning, and the coding of the games themselves all bypass the screen and controller to impact the body of the player. Understanding affect as the relationship of the body to the world, video games are therefore a strong affective medium for the horror genre. Three aspects enable video games to have this strong impact: haptic game design mechanics, play conditioning, and game coding. Using the controller as a threshold object, video games physically interact with players to create a horror experience that compels the body to mirror the fear on screen. Additionally, horror games condition players to play them in a specific way to heighten tension and deny control. Finally, the coding of horror games can create obstacles that deny player control and create an environment of fear. The aim of the essay is to explore the effective use of all these elements and mechanics in three games: the 2015 game Until Dawn, the 2016 horror game Amnesia: The Dark Descent, and the 2014 game Alien: Isolation. (VH)

Modelling Intraocular Lens Design Based on Image Analysis

Intraocular lenses (IOLs) are commonly used to treat ocular diseases such as cataracts. The International Organization for Standardization (ISO 11979) recommends examining IOLs using real model eyes with the lenses in situ, although this process can also be simulated in silico with an accurate IOL haptic design. One way to create this design is by using software such as Abaqus, which generates a finite element mesh configuration with a linear element set up and directly tests it in the model eye using the same program. While this process is like those reported in other studies and includes most of the software necessary for generating the result automatically, there is an alternative method for generating the IOL haptic design — microscopic image analysis. The purpose of this study was to evaluate the image quality of IOL using microscopic analysis. Several IOL images were captured using a microscope and the converted into vector images and the steps were repeated after two weeks. The structural changes in the images were measured using the Structural Similarity Index Measure (SSIM). All the tested IOLs have SSIM values greater than 0.7. The greatest value was extracted from the simplest IOL shape design. Our result suggests that image analysis for IOL modelling is a reliable method and best for simple IOL shape design.

Effect of intraocular lens material and haptic design on anterior capsule contraction after cataract surgery: A systematic review and meta-analysis.

To compare anterior capsule contraction (ACC) after cataract surgery with implantation of intraocular lens (IOLs) of different materials and designs. We searched three electronic databases for relevant studies published up to January 1, 2023. Five randomized controlled trails (RCTs) and three cohort studies involving 1,221 eyes were included in quantitative synthesis. We extracted data, assessed their quality independently, and calculated standard mean difference (SMD) using a random-effects model. Six RCTs and one retrospective cohort were included in information summary. The contraction of the anterior capsule opening area in the hydrophilic group was larger than that of the hydrophobic group from one month to one year postoperatively (P < 0.001 and P < 0.001, respectively). Specifically, the hydrophilic group showed greater contraction of the anterior capsule opening area at one month postoperatively (Standardized mean difference [SMD] = -0.73, 95% confidence interval [CI] = -0.93 to -0.52), three months (SMD = -1.04, 95% CI = -1.32 to -0.75), six months (SMD = -0.99, 95% CI = -1.24 to -0.74) and one year (SMD = -1.33, 95% CI = -2.50 to -0.16). As of one year postoperatively, the anterior capsular opening area showed a trend of decreasing over time in both groups (P = 0.046 and P = 0.050, respectively). In information summary, three studies indicated no relationship between haptic design and ACC, while the other four studies reported that the number and shape of haptic would affect ACC. This meta-analysis suggested that the postoperative ACC after the implantation of hydrophobic IOLs was less than that induced by hydrophilic IOLs. Haptic design may also affect the degree of ACC.

AI-Enabled Vibrotactile Feedback-Based Condition Monitoring Framework for Outdoor Mobile Robots

An automated Condition Monitoring (CM) and real-time controlling framework is essential for outdoor mobile robots to ensure the robot’s health and operational safety. This work presents a novel Artificial Intelligence (AI)-enabled CM and vibrotactile haptic-feedback-based real-time control framework suitable for deploying mobile robots in dynamic outdoor environments. It encompasses two sections: developing a 1D Convolutional Neural Network (1D CNN) model for predicting system degradation and terrain flaws threshold classes and a vibrotactile haptic feedback system design enabling a remote operator to control the robot as per predicted class feedback in real-time. As vibration is an indicator of failure, we identified and separated system- and terrain-induced vibration threshold levels suitable for CM of outdoor robots into nine classes, namely Safe, moderately safe system-generated, and moderately safe terrain-induced affected by left, right, and both wheels, as well as severe classes such as unsafe system-generated and unsafe terrain-induced affected by left, right, and both wheels. The vibration-indicated data for each class are modelled based on two sensor data: an Inertial Measurement Unit (IMU) sensor for the change in linear and angular motion and a current sensor for the change in current consumption at each wheel motor. A wearable novel vibrotactile haptic feedback device architecture is presented with left and right vibration modules configured with unique haptic feedback patterns corresponding to each abnormal vibration threshold class. The proposed haptic-feedback-based CM framework and real-time remote controlling are validated with three field case studies using an in-house-developed outdoor robot, resulting in a threshold class prediction accuracy of 91.1% and an effectiveness that, by minimising the traversal through undesired terrain features, is four times better than the usual practice.

Characterizing affiliative touch in humans and its role in advancing haptic design.

An emerging view in cognitive neuroscience holds that the extraction of emotional relevance from sensory experience extends beyond the centralized appraisal of sensation in associative brain regions, including frontal and medial-temporal cortices. This view holds that sensory information can be emotionally valenced from the point of contact with the world. This view is supported by recent research characterizing the human affiliative touch system, which carries signals of soft, stroking touch to the central nervous system and is mediated by dedicated C-tactile afferent receptors. This basic scientific research on the human affiliative touch system is informed by, and informs, technology design for communicating and regulating emotion through touch. Here, we review recent research on the basic biology and cognitive neuroscience of affiliative touch, its regulatory effects across the lifespan, and the factors that modulate it. We further review recent work on the design of haptic technologies, devices that stimulate the affiliative touch system, such as wearable technologies that apply the sensation of soft stroking or other skin-to-skin contact, to promote physiological regulation. We then point to future directions in interdisciplinary research aimed at both furthering scientific understanding and application of haptic technology for health and wellbeing.

Clinical Performance of New Enhanced Monofocal Intraocular Lenses: Comparison of Hydrophobic C-loop and Hydrophilic Plate-Haptic Platform.

Enhanced monofocal intraocular lenses (IOLs) represent a new type of lens, which should lead to a very good distance vision similar to monofocal IOLs and an improved intermediate vision without increasing the risk for photic phenomena. The aim of this clinical observation/registry study was to directly compare two different IOL platforms (hydrophilic acrylic L-333 (groupA) vs hydrophobic acrylic AN6Q (groupB)) with the same enhanced monofocal optic principle but different material and haptic design in clinical routine. A total of 102 cataract cases (51:51) were included in the study. Groups A and B were similar regarding demographics, age (71.6 ± 9years for L-333 and 73.6 ± 8years for AN6Q) and their calculated IOL power (20.9 ± 2.0D for L-333 and 21.5 ± 3.4D for AN6Q). Spherical equivalent (SE), (un)corrected distance, intermediate visual acuity, the surgeons' experience and patient feedback were assessed postoperatively. SE improved significantly in the AN6Q group, while the L-333 group showed a slightly smaller standard deviation postoperatively. In groupA the uncorrected distance visual acuity (UDVA) improved from pre-op (0.43 ± 0.16logMAR) to 1month post-op (0.06 ± 0.04logMAR) significantly and in groupB from pre-op (0.54 ± 0.19logMAR) to (0.05 ± 0.06logMAR) postoperatively. Both groups showed excellent outcomes for distance without negative side effects. On testing uncorrected intermediate vision (80cm) with Radner charts, 80% reached line5 (0.0logRAD) with fewer than one mistake and 10% reached line4 (- 0.1logRAD) in groupA; 74% reached line5 with fewer than one mistake and 4% reached line4 in groupB. Both IOL models (groupsA and B) provided satisfying results regarding implantation behaviour, refractive error, visual acuity and overall patient satisfaction. The haptic design might influence the outcome of refractive error. Long-term follow-up data should be considered in multicentre studies to further characterize both platforms and to optimize IOL power calculation (constants, surgeon factor). It was shown that the enhanced monofocal optic can provide good visual acuity for far distance and improve intermediate distance. This type of new monofocal optic design, which however must be strictly separated from typical refractive/diffractive multifocal, presbyopia-correcting lenses, could be a good option in standard cataract care.

Refractive Outcomes of Intraocular Lenses with Different Haptic Designs Following Phacovitrectomy with Gas Tamponade

Purpose: To compare the refractive outcomes of closed C-loop and C-loop intraocular lenses (IOLs) following phacovitrectomy with gas tamponade.Methods: Medical records of 42 patients (43 eyes) who underwent phacovitrectomy with gas tamponade for idiopathic macular holes between January 2021 and June 2022 were retrospectively reviewed. Closed C-loop (26 eyes; Eyelike K-flex Aspheric&lt;sup&gt;®&lt;/sup&gt;, Koryo Eyetech, Seoul, Korea) and C-loop (17 eyes; Tecnis&lt;sup&gt;®&lt;/sup&gt; ZCB00, Johnson &amp; Johnson Vision, Santa Ana, CA, USA) IOLs were surgically implanted. The main outcome measures were postoperative prediction error and absolute error.Results: There was no significant difference in mean absolute error at 5 months postoperatively (0.34 ± 0.24 diopters [D] and 0.30 ± 0.25 D in the closed C-loop and C-loop IOL groups, respectively; &lt;i&gt;p&lt;/i&gt; = 0.502). The mean prediction error at 5 months postoperatively also showed no significant difference between the groups (-0.28 ± 0.30 D and -0.16 ± 0.36 D, respectively; &lt;i&gt;p&lt;/i&gt; = 0.242). Myopic shift was observed in both groups.Conclusions: There was no significant difference in refractive outcomes between closed C-loop IOLs and C-loop IOLs. A myopic shift was observed in both groups; this should be taken into consideration when calculating IOL power following phacovitrectomy with gas tamponade.

Defining Allowable Stimulus Ranges for Position and Force Controlled Cutaneous Cues.

Haptic cues delivered via wearable devices have great potential to enhance a user's experience by transmitting task information and touch sensations in domains such as virtual reality, teleoperation, and prosthetics. Much is still unknown on how haptic perception, and consequently optimal haptic cue design, varies between individuals. In this work we present three contributions. First, we propose a new metric, the Allowable Stimulus Range (ASR), as a way to capture subject-specific magnitudes for a given cue, using the method of adjustments and the staircase method. Second, we present a modular, grounded, 2-DOF, haptic testbed designed to conduct psychophysical experiments in multiple control schemes and with rapidly-interchangeable haptic interfaces. Third, we demonstrate an application of the testbed and our ASR metric, together with just noticeable differences (JND) measurements, to compare perception of haptic cues delivered via position or force control schemes. Our findings show that users demonstrate higher perceptual resolution in the position-control case, though survey results suggest that force-controlled haptic cues are more comfortable. The results of this work outline a framework to define perceptible and comfortable cue magnitudes for an individual, providing the groundwork to understand haptic variability, and compare the effectiveness of different types of haptic cues.

Evaluation of the mechanical stability of intraocular lenses using digital image correlation

This study aimed to evaluate the mechanical stability of seven different intraocular lens (IOL) haptic designs by using digital image correlation to measure their mechanical biomarkers (axial displacement, tilt, and rotation) under quasi-static compression. The IOLs were compressed between two clamps from 11.00 up to 9.50 mm whilst a 3D deformation dataset was acquired every 0.04 mm. Results revealed that flexible and mixed IOL designs exhibited better mechanical response for smaller compression diameters compared to stiff designs. Conversely, stiff designs performed better for larger compression diameters. These findings may aid in the selection and development of more mechanically stable IOL designs.

Influence of design parameters and capsulorhexis on intraocular lens stabilities: A 3D finite element analysis

BackgroundCurrent treatment of cataract widely used in clinics is by removal of the opacified content from the lens capsule which is followed by insertion of an artificial intraocular lens (IOL). The IOL needs to remain stabilized in the capsular bag for the eye to achieve desired optical quality. The present study aims to investigate how different design parameters of the IOL can influence the axial and rotational stabilities of IOLs using Finite Element Analysis. MethodsEight designs of IOL with variations in types of optics surface, types of haptics and haptic angulation were constructed using parameters obtained from an online IOL databank (IOLs.eu). Each IOL was subjected to compressional simulations both by two clamps and by a collapsed natural lens capsule with an anterior rhexis. Comparisons were made between the two scenarios on axial displacement, rotation, and distribution of stresses. ResultsThe clamps compression method set out by ISO does not always produce the same outcome as the in-the-bag analysis. The open-loop IOLs show better axial stability while the closed-loop IOLs show better rotational stability when compressed by two clamps. Simulations of IOL in the capsular bag only demonstrate better rotational stability for closed-loop designs. ConclusionsThe rotational stability of an IOL is largely dependent on its haptic design whilst the axial stability is affected by the appearance of the rhexis to the anterior capsule which has a major influence on designs with a haptic angulation.