IEEE Transactions on Haptics最新文献

Touch enables humans to recognize the location, motion, shape, and properties of contacted objects in the real world through mechanoreceptors distributed widely across the skin. However, existing tactile displays typically stimulate only the ventral surfaces of the fingers and hands, limiting the range and richness of touch-based interactions in interactive systems. Here, we present FingerWrap, a high-density pneumatic pin-array display that wraps around the finger and activates the widely distributed mechanoreceptors. FingerWrap uses 337 pins arranged at 13 pins/cm$^{2}$, which cover the ventral, dorsal, and lateral surfaces of the finger up to 45mm from the fingertip, enabling precise spatiotemporal stimulation across continuous regions of the finger skin. Across six perceptual experiments, we show that FingerWrap can provide tactile experiences that ventral-only displays cannot achieve. These include the discrimination of stimulus locations and motion trajectories across multiple regions of the finger skin, the recognition of three-dimensional shape features, and the perception of realistic resistance when the finger is immersed in virtual liquids. This display, which enables a rich and realistic touch experience, could serve as a platform for exploring novel tactile interactions and basic scientific research.

Conventional visual-based object recognition is subject to many variables which may cause degradation, such as improper illumination and occlusion. Tactile sensing-based object recognition can assist in situations where these issues occur, enabling a system to exploit features that standard visual systems cannot identify. Tactile sensing-based object recognition involves the gathering and processing of physical features related to the interaction between a tactile sensing system such as a robot, and a physical object. This work proposes a novel object recognition pipeline driven by a multi-sensory tactile fusion model based on the state-of-the-art time-series classifier, MiniROCKET. It builds upon the authors' previously published research, which achieved state-of-the-art performance for single-modality tactile object recognition, and by implementing a collection of classification heads on both the ROCKET and MiniROCKET pipelines. This work demonstrates how the combination of multiple tactile sensing modalities can achieve excellent performance, exceeding the performance of current systems which use a combination of both visual and tactile systems. This research achieves a state-of-the-art performance on the PHAC-2 dataset, exceeding what was previously achieved in accuracy by 3.3% while simultaneously reducing computational costs by up to 90%.

We present the development and evaluation of the TMouse, a new iteration of a haptic device designed to enhance the tactile presentation of 2.5D images, for instance for visually impaired users. The TMouse builds on an earlier design, targeting a reduced, compact size, as well as more stable tactile rendering. The system employs a set of 3×3 linear actuators moving a triangular surface to deliver tactile feedback directly to a user's fingertips. A comprehensive user study was conducted to assess the device's performance for rendering 2.5D shapes. In contrast to pilot studies comprising the earlier design, in this work different interaction modes were investigated, as well as more complex tactile shapes, also including distractors in a forced-choice task. Regarding the former, participants were asked to identify the tactile profiles, when exploring either freely, or guided, or passively with the haptic mouse. Results showed no significant difference in recognition rates, with regard to exploration condition; however, participants clearly preferred the option of free exploration. The accuracy of shape detection was mostly influenced by the shape complexity, as well as the similarity to the distractor shapes. Finally, a slight learning effect in recognition rates for some shapes was observed over the course of the study. Overall, the new device design and the study insights can provide guidance for future development of similar haptic mouse-type systems, aiming at fingertip tactile display of data.

Electrical stimulation virtual vibration is widely used in fields like virtual reality and medical rehabilitation. However, its parameter optimization still relies on subjective psychological evaluation. This approach lacks objective quantitative criteria. The purpose of this paper is to investigate the neural response relationship between low-frequency vibration stimulation and electrical stimulation using EEG technology, providing quantitative theoretical support for optimizing electrical stimulation parameters. This paper employs a custom-built electrical stimulation system (incorporating a flexible electrode array) to conduct tactile EEG experiments with 42 participants under both electrical stimulation and vibration stimulation conditions. We extract beta-band power spectral density (PSD) and regional permutation entropy (PE) features for the two types of stimulation. Results demonstrate that under vibration stimulation, PSD at C6 and T8 channels exhibit positive correlation with frequency, while PE in the right central region and right temporal-frontal-parietal region shows positive correlation with amplitude. During electrical stimulation, corresponding neural features follow analogous patterns. For both modalities, PSD-frequency correlations (Pearson's r > 0.84) and PE-amplitude correlations (r > 0.68) achieve statistically significant levels. Finally, we conducted classification experiments using a k-nearest neighbor (kNN) classifier, with EEG features from vibratory stimulation as the training set and EEG features from electrical stimulation as the test set. The results show that the accuracy reached 66.7% for the frequency discrimination task, while the average accuracy for the amplitude discrimination task was 67.9%. These findings demonstrate significant similarity in neural signatures elicited by low-frequency vibration stimulation (1-15 Hz) and electrical stimulation. Our study provides new insights for quantifying the refinement of electrical stimulation parameters.

In minimally invasive procedures involving puncture techniques, as robotic-assisted surgical systems continue to evolve, haptic feedback technology has emerged as a critical enabler for enhancing the operator's perceptual capabilities, improving puncture accuracy and reducing the risk of tissue damage. The traditional mechanical haptic feedback may suffer from friction, which affects the haptic interaction experience. In this paper, a magnetic haptic feedback device based on electromagnetic coils is designed, which can dynamically adjust the magnetic field according to the changes in puncture force, thus achieving high-fidelity reproduction of the puncture force. Furthermore, a magnetic haptic feedback algorithm based on three sequential stages-calibration, training, and feedback-is proposed. In the calibration stage, the system obtains the nonlinear mapping between the coil duty cycle and the magnetic force. In the training stage, a residual-connected multilayer perceptron model learns the mapping from force to duty cycle. In the feedback stage, coil currents are dynamically computed according to the target feedback force and current pose, enabling high-precision force reconstruction and real-time magnetic field control. This paper proposes and implements a magnetic haptic feedback system tailored for teleperated robotic puncture tasks, integrating three-dimensional virtual simulation, vision-based servo control for puncture functionality, and a magnetic feedback mechanism based on electromagnetic coils. The system consists of a surgeon-side and a patient-side. The surgeon-side constructs a three-dimensional simulation environment to specify the target puncture point, remotely control the puncture process, and receive real-time force feedback; the patient-side uses a six-degree-of-freedom robotic arm to perform the puncture operation and collects puncture force data during the process, which is then feedback to the surgeon-side. Through phantom experiments and user evaluations, the superior performance of this system in terms of force feedback fidelity and operational immersion has been validated.

Teleoperating mobile manipulators can be cognitively demanding due to a lack of depth perception and situational awareness. While virtual fixture constraints can be used to improve teleoperation performance, it is critical to ensure safety of these fixtures in order to enable their use in physical human-robot-interaction (pHRI) tasks. In this work, we propose to use control barrier functions (CBF) to design a virtual fixture architecture that allows us to tune the tradeoff between performance and safety. We design the architecture to ensure tracking performance between the user and robot is maintained outside of virtual fixture violations, and to simultaneously ensure that the robot cannot overshoot into a constraint. We conducted an analysis to investigate the relationship between tracking and safety, and present results which indicate that the ratio between the control gain used for tracking and the safety decay rate determine when the CBF filter and CBF-based force feedback become active. Finally, we implemented our proposed virtual fixture architecture on a mobile manipulator platform to investigate its effects on user's performance as they performed a simulated temperature scanning task. Overall, this work highlights the potential benefits of using CBF-based haptic virtual fixtures for conducting pHRI tasks.

Illusory pulling sensations, induced by asymmetric vibrations applied to the fingertips, have attracted attention as a means to investigate sensorimotor processing and develop haptic interfaces. In addition, sensitivity to the illusory pulling sensation tended to decline in some older female participants, suggesting that factors related to aging and/or gender difference may be involved in this phenomenon. In this study, we aimed to clarify the contribution of somatosensory and cognitive functions to the illusory pulling sensation, focusing on aging and gender difference to examine these contributions. Sixty older participants aged 63 to 80 years (30 males, 30 females) completed seven assessments, covering sensitivity to the illusory pulling sensation and a range of somatosensory and cognitive functions from vibration detection thresholds to general cognitive ability assessed by the Mini-Mental State Examination (MMSE). Consistent with prior findings, older females exhibited significantly lower sensitivity to the illusion. Interestingly, although gender differences were observed in some of the assessment items, such as hand length and performance on the parallel-setting task, none of these factors mediated the gender effect on the illusion. While age itself did not have a direct effect on the illusion, an indirect effect was observed through general cognitive function as assessed by the MMSE. These findings suggest that the illusory pulling sensation tends to weaken not only with aging, but also particularly when aging is accompanied by cognitive decline. Overall, gender and cognitive function may play key roles in individual differences in the illusory pulling sensation.

Wearable haptic gloves have the potential to greatly enhance active touch experiences in virtual reality (VR). However, it remains unclear how well people can interpret glove-enabled virtual touch experiences when experienced passively (for example, when they passively view a virtual hand perform autonomous actions while also feeling what the virtual hand feels via a haptic glove). Such a "haptic replay" scenario could enable people to share, revisit, or demonstrate touch-critical experiences, including medical palpation or fine manipulation of tools. This study explores a virtual user's ability to interpret one tactile feature, object size, when receiving touch feedback from a commercial haptic glove during either an active or passive grasp interaction. Although passive conditions resulted in poorer size acuity than during active touch, passive performance improved when participants mimicked the motion of the virtual hand, underscoring the role of proprioceptive feedback in grasp interpretation. Additionally, gender differences in performance suggest potential influences of glove ergonomics and size congruency between the real and virtual hand. Future research should investigate these variables and strive for balanced gender representation to assess generalization across VR applications.