Search Results (87)

Hand gestures are essential for interaction in augmented and virtual reality (AR/VR), allowing users to intuitively manipulate virtual objects and engage with human–machine interfaces (HMIs). Accurate gesture recognition is critical for effective task execution. However, users often encounter difficulties due to the lack of immediate and clear feedback from head-mounted displays (HMDs). Current tracking technologies cannot always guarantee reliable recognition, leaving users uncertain about whether their gestures have been successfully detected. To address this limitation, haptic feedback can play a key role by confirming gesture recognition and compensating for discrepancies between the visual perception of fingertip contact with virtual objects and the actual system recognition. The goal of this paper is to compare a simple vibrotactile ring with a full glove device and identify their possible improvements for a fundamental gesture like pinching and fine moving of objects using Microsoft HoloLens 2. Where the pinch action is considered an essential fine motor skill, augmented reality integrated with haptic feedback can be useful to notify the user of the recognition of the gestures and compensate for misaligned visual perception between the tracked fingertip with respect to virtual objects to determine better performance in terms of spatial precision. In our experiments, the participants’ median distance error using bare hands over all axes was 10.3 mm (interquartile range [IQR] = 13.1 mm) in a median time of 10.0 s (IQR = 4.0 s). While both haptic devices demonstrated improvement in participants precision with respect to the bare-hands case, participants achieved with the full glove median errors of 2.4 mm (IQR = 5.2) in a median time of 8.0 s (IQR = 6.0 s), and with the haptic rings they achieved even better performance with median errors of 2.0 mm (IQR = 2.0 mm) in an even better median time of only 6.0 s (IQR= 5.0 s). Our outcomes suggest that simple devices like the described haptic rings can be better than glove-like devices, offering better performance in terms of accuracy, execution time, and wearability. The haptic glove probably compromises hand and finger tracking with the Microsoft HoloLens 2. Full article

Background: Traditionally, auditory rehabilitation in people with hearing loss has sought training in auditory skills to achieve an understanding of sound messages for communication. Assistive or supportive technology is limited to hearing aids that transmit sound through the air or bone to be used by the individual, and only in recent times have technologies for rehabilitation, of high cost and difficult access, begun to be used, employed by audiology professionals. Objective: The objective of this study was to compile the evidence reported in the literature on the use of technology in auditory rehabilitation for the improvement of hearing skills in people with hearing loss, beyond hearing aids and cochlear implants. Method: A systematic review of the literature was conducted between 2018 and 2024 in PubMed, Scopus, and Web of Science databases, using as search terms Technology AND “Auditory Rehabilitation” validated in DeCS and MeSH thesauri; the PICO method was used to propose the research question, and the PRISMA strategy was used for the inclusion or exclusion of the articles to be reviewed. Results: In the first search, 141 documents were obtained. Subsequently, inclusion criteria, such as development with vibrotactile stimulation, Information and Communication Technologies (ICTs), among others, and exclusion criteria, such as those related to cochlear implants and air conduction hearing aids, were applied, and finally, articles related to natural language processing, and other systematic reviews were excluded so that the database was reduced to 14 documents. To this set, due to their relevance, two papers were added, for a total of sixteen analyzed. Conclusions: There are solutions ranging from the use of smartphones for telehealth to solutions with multiple technologies, such as the development of virtual environments with vibrotactile feedback. Hearing-impaired people and even professionals in this area of healthcare have a high level of acceptance of the use of technology in rehabilitation. Finally, this article highlights the crucial role of technology in auditory rehabilitation, with solutions that improve hearing skills and the positive acceptance of these tools by patients and audiology professionals. Full article

This study presents a novel investigation into immersive teleoperation systems using collaborative, device-agnostic interfaces for advancing smart haptics in industrial assistive applications. The research focuses on evaluating the quality of experience (QoE) of users interacting with a teleoperation system comprising a local robotic arm, a robot gripper, and heterogeneous remote tracking and haptic feedback devices. By employing a modular device-agnostic framework, the system supports flexible configurations, including one-user-one-equipment (1U-1E), one-user-multiple-equipment (1U-ME), and multiple-users-multiple-equipment (MU-ME) scenarios. The experimental set-up involves participants manipulating predefined objects and placing them into designated baskets by following specified 3D trajectories. Performance is measured using objective QoE metrics, including temporal efficiency (time required to complete the task) and spatial accuracy (trajectory similarity to the predefined path). In addition, subjective QoE metrics are assessed through detailed surveys, capturing user perceptions of presence, engagement, control, sensory integration, and cognitive load. To ensure flexibility and scalability, the system integrates various haptic configurations, including (1) a Touch kinaesthetic device for precision tracking and grounded haptic feedback, (2) a DualSense tactile joystick as both a tracker and mobile haptic device, (3) a bHaptics DK2 vibrotactile glove with a camera tracker, and (4) a SenseGlove Nova force-feedback glove with VIVE trackers. The modular approach enables comparative analysis of how different device configurations influence user performance and experience. The results indicate that the objective QoE metrics varied significantly across device configurations, with the Touch and SenseGlove Nova set-ups providing the highest trajectory similarity and temporal efficiency. Subjective assessments revealed a strong correlation between presence and sensory integration, with users reporting higher engagement and control in scenarios utilizing force feedback mechanisms. Cognitive load varied across the set-ups, with more complex configurations (e.g., 1U-ME) requiring longer adaptation periods. This study contributes to the field by demonstrating the feasibility of a device-agnostic teleoperation framework for immersive industrial applications. It underscores the critical interplay between objective task performance and subjective user experience, providing actionable insights into the design of next-generation teleoperation systems. Full article

Rendering surface materials to provide realistic tactile sensations is a key focus in haptic interaction research. However, generating texture maps and designing corresponding haptic feedback often requires expert knowledge and significant effort. To simplify the workflow, we developed a micro-collision-based tactile texture dataset for several common materials and fine-tuned the VAE model of Stable Diffusion. Our approach allows designers to generate matching visual and haptic textures from natural language prompts and enables users to receive real-time, realistic haptic feedback when interacting with virtual surfaces. We evaluated our method through a haptic design task. Professional and non-haptic designers each created one haptic design using traditional tools and another using our approach. Participants then evaluated the four resulting designs. The results showed that our method produced haptic feedback comparable to that of professionals, though slightly lower in overall and consistency scores. Importantly, professional designers using our method required less time and fewer expert resources. Non-haptic designers also achieved better outcomes with our tool. Our generative method optimizes the haptic design workflow, lowering the expertise threshold and increasing efficiency. It has the potential to support broader adoption of haptic design in interactive media and enhance multisensory experiences. Full article

Musculoskeletal disorders are prevalent among medical professionals like dentists, who often maintain prolonged, ergonomically disadvantageous postures. This study aims to evaluate the feasibility and efficacy of a wearable sensor-based monitoring and feedback system designed to improve posture and evaluate muscle recruitment. Thirty-five healthy adults participated in a controlled experiment, performing a typing task under various postural conditions with and without haptic feedback. Surface electromyography sensors measured muscle activity in the upper trapezius and infraspinatus muscles, while inertial measurement units tracked spine orientation. The results indicated that haptic feedback significantly influenced muscle activity and posture. Feedback reduced deviations from the desired postures but increased muscle activity in certain conditions. Cognitive performance, measured by typing speed, decreased with feedback, suggesting a trade-off between maintaining posture and the performance of the task. These findings highlight the potential of haptic feedback in ergonomic interventions to mitigate MSDs. Future research should explore the long-term effects and optimize feedback mechanisms to balance posture correction and cognitive demands. Full article

Teleoperation enables robots to perform tasks in dangerous or hard-to-reach environments on behalf of humans, but most methods lack operator immersion and compliance during grasping. To significantly enhance the operator’s sense of immersion and achieve more compliant and adaptive grasping of objects, we introduce a novel teleoperation method for dexterous robotic hands. This method integrates finger-to-finger force and vibrotactile feedback based on the Fuzzy Logic-Dynamic Compliant Primitives (FL-DCP) controller. It employs fuzzy logic theory to identify the stiffness of the object being grasped, facilitating more effective manipulation during teleoperated tasks. Utilizing Dynamic Compliant Primitives, the robotic hand implements adaptive impedance control in torque mode based on stiffness identification. Then the immersive bilateral teleoperation system integrates finger-to-finger force and vibrotactile feedback, with real-time force information from the robotic hand continuously transmitted back to the operator to enhance situational awareness and operational judgment. This bidirectional feedback loop increases the success rate of teleoperation and reduces operator fatigue, improving overall performance. Experimental results show that this bio-inspired method outperforms existing approaches in compliance and adaptability during teleoperation grasping tasks. This method mirrors how human naturally modulate muscle stiffness when interacting with different objects, integrating human-like decision-making and precise robotic control to advance teleoperated systems and pave the way for broader applications in remote environments. Full article

(1) Background: The safe execution of heavy machinery operations and high-risk construction tasks requires operators to manage multiple tasks, with a constant awareness of coworkers and hazards. With high demands on visual and auditory resources, vibrotactile feedback systems offer a solution to enhance awareness without overburdening vision or hearing. (2) Aim: This study evaluates the impact of vibrotactile feedback regarding proximity to hazards on multitasking performance and cognitive workload in order to support hazard awareness in a controlled task environment. (3) Method: Twenty-four participants performed a joystick-controlled navigation task and a concurrent mental spatial rotation task. Proximity to hazards in the navigation task was conveyed via different encodings of vibrotactile feedback: No Vibration, Intensity-Modulation, Pulse Duration, and Pulse Spacing. Performance metrics, including obstacle collisions, target hits, contact time, and accuracy, were assessed alongside perceived workload. (4) Results: Intensity-Modulated feedback reduced obstacle collisions and proximity time, while lowering workload, compared to No Vibration. No significant effects were found on spatial rotation accuracy, indicating that vibrotactile feedback effectively guides navigation and supports spatial awareness. (5) Conclusions: This study highlights the potential of vibrotactile feedback to improve navigation performance and hazard awareness, offering valuable insights into multimodal safety systems in high-demand environments. Full article

While autonomous wheelchairs reduce the burden on passengers, automation can make it difficult for them to anticipate the future path of the wheelchair, potentially causing anxiety or discomfort due to unexpected movements. In this study, we define “path” as the geometric trajectory of the wheelchair position, without considering temporal aspects. Providing passengers with information about this future path is crucial, particularly when multiple pedestrians or obstacles are present. Previous studies have primarily focused on presenting only the direction in which the wheelchair turns. In this study, we propose a path presentation method that conveys both the direction and width of turns by varying the duration of haptic apparent motion according to the turning width. The results from the evaluation experiment showed that presenting the future path, including the extent of avoidance maneuvers, improved user understanding and offered a slightly greater sense of security compared to methods that presented only directional information or no feedback at all. Full article

Background: Research on sensory feedback systems for prosthetic devices aims to enhance sensory capabilities to better meet user needs. Feedback systems for lower limb amputees (LLA) have been shown to reduce cognitive efforts, metabolic cost and phantom limb pain. This study evaluated the effect of a non-invasive, gait-synchronized, vibrotactile feedback system (VTFS) on the gait parameters of LLA. Methods: Four stimulators applied vibrotactile stimulation to the thigh of LLA during walking, corresponding to four pressure sensors located at the fore- and hindfoot embedded in a sock worn on the prosthetic foot. Standardized gait tests, such as the Timed “Up and Go” Test (TUG), the Four Square Step Test (FSST), the 10 Meter Walk Test (10 MWT) and the 2 Minute Walk Test (2 MWT), were performed to assess the risk of falling, coordination, walking speed and endurance before and after intervention. Results: After an average of 61.5 days using the VTFS, gait stability (TUG) improved significantly. Coordination (FSST) improved in 36% of subjects, while 45% showed a clinically relevant increase in gait speed (10 MWT). Conclusions: The results suggest an improved gait performance in the cohort. Though FSST lacked statistical significance, a p-value near 0.05 indicates a trend toward meaningful improvement. Notably, the participant with Targeted Sensory Reinnervation demonstrated the most favorable outcomes. Full article

Haptics for stress regulation is well developed these years. Using vibrotactile to present biofeedback, guiding breathing or heartbeat regulation is a dominant technical approach. However, designing computer-mediated affective touch for stress regulation is also a promising way and has not been fully explored. In this paper, a haptic device was developed to test whether the computer-mediated affective stroking on the forearm could help to assist people in reducing stress. In our method, we used mid-air technology to generate subtle pressure force by blowing air and generating thermal feedback by using Peltier elements simultaneously. Firstly, we found intensity and velocity parameters to present comfort and pleasant stroking sensations. Afterward, an experiment was conducted to find out whether this approach could help people mediate their perceived and physiological stress. A total of 49 participants were randomly assigned to either a Stroking Group (SG) or a Control Group (CG). Results showed that participants from SG felt more relaxed than those from CG. The physiological stress index, RMSSD, increased and LF/HF decreased in SG although these changes were not statistically significant. Our exploration created subtle, non-invasive, noiseless haptic sensations. It could be a promising alternative for assisting people in stress regulation. Design implications and future applicable scenarios were discussed. Full article

Current XR applications move beyond audiovisual information, with haptic feedback rapidly gaining ground. However, current haptic devices are still evolving and often struggle to combine key desired features in a balanced way. In this paper, we propose the development of a high-resolution haptic (HRH) system for perception enhancement, a wearable technology designed to augment extended reality (XR) experiences through precise and localized tactile feedback. The HRH system features a modular design with 58 individually addressable actuators, enabling intricate haptic interactions within a compact wearable form. Dual ESP32-S3 microcontrollers and a custom-designed system ensure robust processing and low-latency performance, crucial for real-time applications. Integration with the Unity game engine provides developers with a user-friendly and dynamic environment for accurate, simple control and customization. The modular design, utilizing a flexible PCB, supports a wide range of actuators, enhancing its versatility for various applications. A comparison of our proposed system with existing solutions indicates that the HRH system outperforms other devices by encapsulating several key features, including adjustability, affordability, modularity, and high-resolution feedback. The HRH system not only aims to advance the field of haptic feedback but also introduces an intuitive tool for exploring new methods of human–computer and XR interactions. Future work will focus on refining and exploring the haptic feedback communication methods used to convey information and expand the system’s applications. Full article

Virtual reality (VR) offers immersive visual and auditory experiences, transporting users to alternate realities. However, existing VR systems lack realistic haptic feedback mechanisms, resulting in unsatisfactory immersive experiences. In this study, we developed and tested a haptic glove that simulates realistic tactile sensations, enhancing user interaction with virtual artifacts. Our research investigates the impact of finger-specific vibrotactile feedback (FSVF) on user experience in virtual museum environments. Using a mixed-methods approach, 30 participants engaged in object-manipulation tasks in three settings: no haptic feedback, standard controller feedback, and vibrotactile glove feedback. The findings demonstrate that the vibrotactile glove approach considerably improves user accuracy, efficiency, immersion, and satisfaction compared with other traditional interaction methods. Participants completed tasks more accurately and quickly with the glove, reporting high levels of engagement and immersion. The results highlight the potential of advanced haptic feedback in transforming virtual reality technology, particularly for educational and cultural applications. Further, they provide valuable insights for designing and applying future haptic technology in immersive environments. Full article

People use their hands for intricate tasks like playing musical instruments, employing myriad touch sensations to inform motor control. In contrast, current prosthetic hands lack comprehensive haptic feedback and exhibit rudimentary multitasking functionality. Limited research has explored the potential of upper limb amputees to feel, perceive, and respond to multiple channels of simultaneously activated haptic feedback to concurrently control the individual fingers of dexterous prosthetic hands. This study introduces a novel control architecture for three amputees and nine additional subjects to concurrently control individual fingers of an artificial hand using two channels of context-specific haptic feedback. Artificial neural networks (ANNs) recognize subjects’ electromyogram (EMG) patterns governing the artificial hand controller. ANNs also classify the directions objects slip across tactile sensors on the robotic fingertips, which are encoded via the vibration frequency of wearable vibrotactile actuators. Subjects implement control strategies with each finger simultaneously to prevent or permit slip as desired, achieving a 94.49% ± 8.79% overall success rate. Although no statistically significant difference exists between amputees’ and non-amputees’ success rates, amputees require more time to respond to simultaneous haptic feedback signals, suggesting a higher cognitive load. Nevertheless, amputees can accurately interpret multiple channels of nuanced haptic feedback to concurrently control individual robotic fingers, addressing the challenge of multitasking with dexterous prosthetic hands. Full article

Humans interact with the environment through a variety of senses. Touch in particular contributes to a sense of presence, enhancing perceptual experiences, and establishing causal relations between events. Many human–machine interfaces only allow for one-way communication, which does not do justice to the complexity of the interaction. To address this, we developed a bidirectional human–machine interface featuring a bracelet equipped with linear resonant actuators, controlled via a Robot Operating System (ROS) program, to simulate haptic feedback. Further, the wireless interface includes a motion sensor and a sensor to quantify the tightness of the bracelet. Our functional experiments, which compared stimulation with three and five intensity levels, respectively, were performed by four healthy participants in their twenties and thirties. The participants achieved an average accuracy of 88% estimating three vibration intensity levels. While the estimation accuracy for five intensity levels was only 67%, the results indicated a good performance in perceiving relative vibration changes with an accuracy of 82%. The proposed haptic feedback bracelet will facilitate research investigating the benefits of bidirectional human–machine interfaces and the perception of vibrotactile feedback in general by closing the gap for a versatile device that can provide high-density user feedback in combination with sensors for intent detection. Full article

Haptic feedback holds the potential to enhance the engagement and expressivity of future digital and electric musical instruments. This study investigates the impact of artificial vibration on the perceived quality of a silent electric cello. We developed a haptic cello prototype capable of rendering vibration signals of varying degree of congruence with the produced sound. Experienced cellists participated in an experiment comparing setups with and without vibrotactile feedback, rating them on preference, perceived power, liveliness, and feel. Results show nuanced effects, with added vibrations moderately enhancing feel and liveliness, and significantly increasing perceived power when using vibrations obtained from the pickup at the cello’s bridge. High uncertainty in our statistical model parameters underscores substantial individual differences in the participants responses, as commonly found in qualitative assessments, and highlights the importance of consistent feedback in the vibrotactile and auditory channels. Our findings contribute valuable insights to the intersection of haptics and music technology, paving the way for creating richer and more engaging experiences with future musical instruments. Full article