scholarly journals A closed-loop hand prosthesis with simultaneous intraneural tactile and position feedback

2019 ◽  
Vol 4 (27) ◽  
pp. eaau8892 ◽  
Author(s):  
Edoardo D’Anna ◽  
Giacomo Valle ◽  
Alberto Mazzoni ◽  
Ivo Strauss ◽  
Francesco Iberite ◽  
...  

Current myoelectric prostheses allow transradial amputees to regain voluntary motor control of their artificial limb by exploiting residual muscle function in the forearm. However, the overreliance on visual cues resulting from a lack of sensory feedback is a common complaint. Recently, several groups have provided tactile feedback in upper limb amputees using implanted electrodes, surface nerve stimulation, or sensory substitution. These approaches have led to improved function and prosthesis embodiment. Nevertheless, the provided information remains limited to a subset of the rich sensory cues available to healthy individuals. More specifically, proprioception, the sense of limb position and movement, is predominantly absent from current systems. Here, we show that sensory substitution based on intraneural stimulation can deliver position feedback in real time and in conjunction with somatotopic tactile feedback. This approach allowed two transradial amputees to regain high and close-to-natural remapped proprioceptive acuity, with a median joint angle reproduction precision of 9.1° and a median threshold to detection of passive movements of 9.5°, which was comparable with results obtained in healthy participants. The simultaneous delivery of position information and somatotopic tactile feedback allowed both amputees to discriminate the size and compliance of four objects with high levels of performance (75.5%). These results demonstrate that tactile information delivered via somatotopic neural stimulation and position information delivered via sensory substitution can be exploited simultaneously and efficiently by transradial amputees. This study paves a way to more sophisticated bidirectional bionic limbs conveying richer, multimodal sensations.

2018 ◽  
Author(s):  
Edoardo D’Anna ◽  
Giacomo Valle ◽  
Alberto Mazzoni ◽  
Ivo Strauss ◽  
Francesco Iberite ◽  
...  

Current myoelectric prostheses allow upper-limb amputees to regain voluntary motor control of their artificial limb by exploiting residual muscle function in the forearm1. However, the over-reliance on visual cues resulting from a lack of sensory feedback is a common complaint2,3. Recently, several groups have provided tactile feedback in upper-limb amputees by using implanted electrodes4,5,6,7,8, surface nerve stimulation9,10 or sensory substitution11,12. These approaches have led to improved function and prosthesis embodiment4,5,6,7,13,14. Nevertheless, the provided information remains limited to a subset of the rich sensory cues available to healthy individuals. More specifically, proprioception, the sense of limb position and movement, is predominantly absent from current systems. Here we show that sensory substitution based on intraneural stimulation can deliver position feedback in real-time and in conjunction with somatotopic tactile feedback. This approach allowed two trans-radial amputees to regain high and close-to-natural remapped proprioceptive acuity, with a median joint angle reproduction accuracy of 9.1° and a median threshold to detection of passive movements of 9.5°, which was compatible with results obtained in healthy subjects15,16,17. The simultaneous delivery of position information and somatotopic tactile feedback allowed both amputees to discriminate object size and compliance with high levels of accuracy (75.5%). These results demonstrate that touch information delivered via somatotopic neural stimulation and position information delivered via sensory substitution can be exploited simultaneously and efficiently by trans-radial amputees. This study paves the way towards more sophisticated bidirectional bionic limbs conveying rich, multimodal sensations.


2021 ◽  
Vol 5 (ISS) ◽  
pp. 1-17
Author(s):  
Yosra Rekik ◽  
Edward Lank ◽  
Adnane Guettaf ◽  
Prof. Laurent Grisoni

Alongside vision and sound, hardware systems can be readily designed to support various forms of tactile feedback; however, while a significant body of work has explored enriching visual and auditory communication with interactive systems, tactile information has not received the same level of attention. In this work, we explore increasing the expressivity of tactile feedback by allowing the user to dynamically select between several channels of tactile feedback using variations in finger speed. In a controlled experiment, we show that a user can learn the dynamics of eyes-free tactile channel selection among different channels, and can reliable discriminate between different tactile patterns during multi-channel selection with an accuracy up to 90% when using two finger speed levels. We discuss the implications of this work for richer, more interactive tactile interfaces.


2020 ◽  
Vol 34 (05) ◽  
pp. 8269-8276
Author(s):  
Yang Li ◽  
Guodong Long ◽  
Tao Shen ◽  
Tianyi Zhou ◽  
Lina Yao ◽  
...  

Distantly supervised relation extraction intrinsically suffers from noisy labels due to the strong assumption of distant supervision. Most prior works adopt a selective attention mechanism over sentences in a bag to denoise from wrongly labeled data, which however could be incompetent when there is only one sentence in a bag. In this paper, we propose a brand-new light-weight neural framework to address the distantly supervised relation extraction problem and alleviate the defects in previous selective attention framework. Specifically, in the proposed framework, 1) we use an entity-aware word embedding method to integrate both relative position information and head/tail entity embeddings, aiming to highlight the essence of entities for this task; 2) we develop a self-attention mechanism to capture the rich contextual dependencies as a complement for local dependencies captured by piecewise CNN; and 3) instead of using selective attention, we design a pooling-equipped gate, which is based on rich contextual representations, as an aggregator to generate bag-level representation for final relation classification. Compared to selective attention, one major advantage of the proposed gating mechanism is that, it performs stably and promisingly even if only one sentence appears in a bag and thus keeps the consistency across all training examples. The experiments on NYT dataset demonstrate that our approach achieves a new state-of-the-art performance in terms of both AUC and top-n precision metrics.


1994 ◽  
Vol 3 (1) ◽  
pp. 73-80 ◽  
Author(s):  
Motoyuki Akamatsu ◽  
Sigeru Sato ◽  
I. Scott MacKenzie

A mouse was modified to add tactile and force display. Tactile feedback, or display, was added via a solenoid driving a small pin protruding through a hole in the mouse button. Force feedback was added via an electromagnet and an iron mouse pad. Both enhancements were embedded in the mouse casing, increasing its weight from 103 to 148 g. In a target selection task experiment, the addition of tactile information feedback reduced target selection times slightly, compared to the no additional feedback condition. A more pronounced effect was observed on the clicking time—the time to selection once the cursor entered the target. In this case, we observed a statistically significant speed-up of about 12% in the presence of tactile feedback. The modified mouse was also used in a test of virtual texture. The amplitude and frequency of solenoid pulses were varied according to the movement of the mouse and the underlying virtual texture. Subjects could reliably discriminate between different textures.


2006 ◽  
Vol 5 (2) ◽  
pp. 37-44 ◽  
Author(s):  
Paul Richard ◽  
Damien Chamaret ◽  
François-Xavier Inglese ◽  
Philippe Lucidarme ◽  
Jean-Louis Ferrier

This paper presents a human-scale virtual environment (VE) with haptic feedback along with two experiments performed in the context of product design. The user interacts with a virtual mock-up using a large-scale bimanual string-based haptic interface called SPIDAR (Space Interface Device for Artificial Reality). An original self-calibration method is proposed. A vibro-tactile glove was developed and integrated to the SPIDAR to provide tactile cues to the operator. The purpose of the first experiment was: (1) to examine the effect of tactile feedback in a task involving reach-and-touch of different parts of a digital mock-up, and (2) to investigate the use of sensory substitution in such tasks. The second experiment aimed to investigate the effect of visual and auditory feedback in a car-light maintenance task. Results of the first experiment indicate that the users could easily and quickly access and finely touch the different parts of the digital mock-up when sensory feedback (either visual, auditory, or tactile) was present. Results of the of the second experiment show that visual and auditory feedbacks improve average placement accuracy by about 54 % and 60% respectively compared to the open loop case


2021 ◽  
Author(s):  
Yasser Abdelrahman ◽  
Michael Bennington ◽  
Jessica Huberts ◽  
Samira Sebt ◽  
Nipun Talwar ◽  
...  

2012 ◽  
Vol 21 (4) ◽  
pp. 435-451 ◽  
Author(s):  
Laura Santos-Carreras ◽  
Kaspar Leuenberger ◽  
Evren Samur ◽  
Roger Gassert ◽  
Hannes Bleuler

Robotic surgery provides many benefits such as reduced invasiveness and increased dexterity. This comes at the cost of no direct contact between surgeon and patient. This physical separation prevents surgeons from performing direct haptic exploration of tissues and organs, imposing exclusive reliance on visual cues. Current technology is not yet able to both measure and reproduce a realistic and complete sense of touch (interaction force, temperature, roughness, etc.). In this paper, we put forward a concept based on multimodal feedback consisting of the integration of different kinds of visual and tactile cues with force feedback that can potentially improve both the surgeon's performance and the patient's safety. We present a cost-effective tactile display simulating a pulsating artery that has been integrated into a haptic workstation to combine both tactile and force-feedback information. Furthermore, we investigate the effect of different feedback types, including tactile and/or visual cues, on the performance of subjects carrying out two typical palpation tasks: (1) exploring a tissue to find a hidden artery and (2) identifying the orientation of a hidden artery. The results show that adding tactile feedback significantly reduces task completion time. Moreover, for high difficulty levels, subjects perform better with the feedback condition combining tactile and visual cues. As a matter of fact, the majority of the subjects in the study preferred this combined feedback because redundant feedback reassures subjects in their actions. Based on this work, we can infer that multimodal haptic feedback improves subjects' performance and confidence during exploratory procedures.


2021 ◽  
Vol 15 ◽  
Author(s):  
Justin Tanner ◽  
Gerrit Orthlieb ◽  
David Shumate ◽  
Stephen Helms Tillery

Proprioceptive error of estimated fingertip position in two-dimensional space is reduced with the addition of tactile stimulation to the fingertip. This tactile input does not disrupt the subjects’ estimation strategy, as the individual error vector maps maintain their overall geometric structure. This relationship suggests an integration of proprioception and tactile sensory information to enhance proprioceptive estimation. To better understand this multisensory integration, we explored the effect of electrotactile and vibrotactile stimulation to the fingertips in place of actual contact, thus limiting interaction forces. This allowed us to discern any proprioceptive estimation improvement that arose from purely tactile stimulation. Ten right-handed and ten left-handed subjects performed a simple right-handed proprioceptive estimation task under four tactile feedback conditions: hover, touch, electrotactile, and vibrotactile. Target sets were generated for each subject, persisted across all feedback modalities, and targets were presented in randomized orders. Error maps across the workspace were generated using polynomial models of the subjects’ responses. Error maps did not change shape between conditions for any right-handed subjects and changed for a single condition for two left-handed subjects. Non-parametric statistical analysis of the error magnitude shows that both modes of sensory substitution significantly reduce error for right-handed subjects, but not to the level of actual touch. Left-handed subjects demonstrated increased error for all feedback conditions compared to hover. Compared to right-handed subjects, left-handed subjects demonstrated more error in each condition except the hover condition. This is consistent with the hypothesis that the non-dominant hand is specialized for position control, while the dominant is specialized for velocity. Notably, our results suggest that non-dominant hand estimation strategies are hindered by stimuli to the fingertip. We conclude that electrotactile and vibrotactile sensory substitution only succeed in multisensory integration when applied to the dominant hand. These feedback modalities do not disrupt established dominate hand proprioceptive error maps, and existing strategies adapt to the novel input and minimize error. Since actual touch provides the best error reduction, sensory substitution lacks some unidentified beneficial information, such as familiarity or natural sensation. This missing component could also be what confounds subjects using their non-dominant hand for positional tasks.


Author(s):  
Dace Dimante ◽  
Ināra Logina ◽  
Marco Sinisi ◽  
Angelika Krūmiņa

Abstract Loss of an arm is a devastating condition that can cross all socioeconomic groups. A major step forward in rehabilitation of amputees has been the development of myoelectric prostheses. Current robotic arms allow voluntary movements by using residual muscle contraction. However, a significant issue is lack of movement control and sensory feedback. These factors play an important role in integration and embodiment of a robotic arm. Without feedback, users rely on visual cues and experience overwhelming cognitive demand that results in poorer use of a prosthesis. The complexity of the afferent system presents a great challenge of creating a closed-loop hand prosthesis. Several groups have shown progress providing sensory feedback for upper limb amputees using robotic arms. Feedback, although still limited, is achieved through direct implantation of intraneural electrodes as well as through non-invasive methods. Moreover, evidence shows that over time some amputees develop a phantom sensation of the missing limb on their stump. This phenomenon can occur spontaneously as well as after non-invasive nerve stimulation, suggesting the possibility of recreating a sensory homunculus of the hand on the stump. Furthermore, virtual reality simulation in combination with mechanical stimulation of skin could augment the sensation phenomenon, leading to better interface between human and robotic arms.


Sign in / Sign up

Export Citation Format

Share Document