Multi-Fingered Grasping and Manipulation in Virtual Environments Using an Isometric Finger Device

In this article we present a new isometric input device for multi-fingered grasping in virtual environments. The device was designed to simultaneously assess forces applied by the thumb, index, and middle finger. A mathematical model of grasping, adopted from the analysis of multi-fingered robot hands, was applied to achieve multi-fingered interaction with virtual objects. We used the concept of visual haptic feedback where the user was presented with visual cues to acquire haptic information from the virtual environment. The virtual object corresponded dynamically to the forces and torques applied by the three fingers. The application of the isometric finger device for multi-fingered interaction is demonstrated in four tasks aimed at the rehabilitation of hand function in stroke patients. The tasks include opening the combination lock on a safe, filling and pouring water from a glass, muscle strength training with an elastic torus, and a force tracking task. The training tasks were designed to train patients' grip force coordination and increase muscle strength through repetitive exercises. The presented virtual reality system was evaluated in a group of healthy subjects and two post-stroke patients (early post-stroke and chronic) to obtain overall performance results. The healthy subjects demonstrated consistent performance with the finger device after the first few trials. The two post-stroke patients completed all four tasks, however, with much lower performance scores as compared to healthy subjects. The results of the preliminary assessment suggest that the patients could further improve their performance through virtual reality training.

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Postural Control Disturbances Induced by Virtual Reality in Stroke Patients

Applied Sciences ◽

10.3390/app11041510 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1510

Author(s):

Charles Morizio ◽

Maxime Billot ◽

Jean-Christophe Daviet ◽

Stéphane Baudry ◽

Christophe Barbanchon ◽

...

Keyword(s):

Virtual Reality ◽

Postural Control ◽

Virtual Environments ◽

Center Of Pressure ◽

Dynamic Condition ◽

Static Condition ◽

Stroke Patients ◽

Post Stroke ◽

Subacute Stroke

People who survive a stroke are often left with long-term neurologic deficits that induce, among other impairments, balance disorders. While virtual reality (VR) is growing in popularity for postural control rehabilitation in post-stroke patients, studies on the effect of challenging virtual environments, simulating common daily situations on postural control in post-stroke patients, are scarce. This study is a first step to document the postural response of stroke patients to different challenging virtual environments. Five subacute stroke patients and fifteen age-matched healthy adults were included. All participants underwent posturographic tests in control conditions (open and closed eyes) and virtual environment without (one static condition) and with avatars (four dynamic conditions) using a head-mounted device for VR. In dynamic environments, we modulated the density of the virtual crowd (dense and light crowd) and the avoidance space with the avatars (near or far). Center of pressure velocity was collected by trial throughout randomized 30-s periods. Results showed that more challenging conditions (dynamic condition) induced greater postural disturbances in stroke patients than in healthy counterparts. Our study suggests that virtual reality environments should be adjusted in light of obtaining more or less challenging conditions.

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Stable or able? Effect of virtual reality stimulation on static balance of post-stroke patients and healthy subjects

Human Movement Science ◽

10.1016/j.humov.2020.102569 ◽

2020 ◽

Vol 70 ◽

pp. 102569

Author(s):

Erika D'Antonio ◽

Gaetano Tieri ◽

Fabrizio Patané ◽

Giovanni Morone ◽

Marco Iosa

Keyword(s):

Virtual Reality ◽

Healthy Subjects ◽

Static Balance ◽

Stroke Patients ◽

Post Stroke

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Simulating Haptic Feedback Using Vision: A Survey of Research and Applications of Pseudo-Haptic Feedback

Presence Teleoperators & Virtual Environments ◽

10.1162/pres.18.1.39 ◽

2009 ◽

Vol 18 (1) ◽

pp. 39-53 ◽

Cited By ~ 131

Author(s):

Anatole Lécuyer

Keyword(s):

Virtual Reality ◽

Virtual Environments ◽

Virtual Environment ◽

Visual Feedback ◽

Vocational Training ◽

Haptic Perception ◽

Haptic Feedback ◽

Virtual Object ◽

Milling Machine ◽

Medical Simulator

This paper presents a survey of the main results obtained in the field of “pseudo-haptic feedback”: a technique meant to simulate haptic sensations in virtual environments using visual feedback and properties of human visuo-haptic perception. Pseudo-haptic feedback uses vision to distort haptic perception and verges on haptic illusions. Pseudo-haptic feedback has been used to simulate various haptic properties such as the stiffness of a virtual spring, the texture of an image, or the mass of a virtual object. This paper describes the several experiments in which these haptic properties were simulated. It assesses the definition and the properties of pseudo-haptic feedback. It also describes several virtual reality applications in which pseudo-haptic feedback has been successfully implemented, such as a virtual environment for vocational training of milling machine operations, or a medical simulator for training in regional anesthesia procedures.

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Control of aperture closure during reach-to-grasp movements in immersive haptic-free virtual reality

10.1101/2020.08.01.232470 ◽

2020 ◽

Author(s):

Madhur Mangalam ◽

Mathew Yarossi ◽

Mariusz P. Furmanek ◽

Eugene Tunik

Keyword(s):

Virtual Reality ◽

Virtual Environments ◽

Skill Acquisition ◽

Haptic Feedback ◽

Virtual Object ◽

Control Law ◽

Reach To Grasp ◽

Control Laws ◽

Transport Velocity ◽

Aperture Closure

AbstractVirtual reality (VR) has garnered much interest as a training environment for motor skill acquisition, including for neurological rehabilitation of upper extremities. While the focus has been on gross upper limb motion, VR applications that involve reaching for, and interacting with, virtual objects are growing. The absence of true haptics in VR when it comes to hand-object interactions raises a fundamentally important question: can haptic-free immersive virtual environments (hf-VEs) support naturalistic coordination of reach-to-grasp movements? This issue has been grossly understudied, and yet is of significant importance in the development and application of VR across a number of sectors. In a previous study (Furmanek et al. 2019), we reported that reach-to-grasp movements are similarly coordinated in both the physical environment (PE) and hf-VE. The most noteworthy difference was that the closure phase—which begins at maximum aperture and lasts through the end of the movement—was longer in hf-VE than in PE, suggesting that different control laws might govern the initiation of closure between the two environments. To do so, we reanalyzed data from Furmanek et al. (2019), in which the participants reached to grasp three differently sized physical objects, and matching 3D virtual object renderings, placed at three different locations. Our analysis revealed two key findings pertaining to the initiation of closure in PE and hf-VE. First, the respective control laws governing the initiation of aperture closure in PE and hf-VE both included state estimates of transport velocity and acceleration, supporting a general unified control scheme for implementing reach-to-grasp across physical and virtual environments. Second, aperture was less informative to the control law in hf-VE. We suggest that the latter was likely because transport velocity at closure onset and aperture at closure onset were less independent in hf-VE than in PE, ultimately resulting in aperture at closure onset having a weaker influence on the initiation of closure. In this way, the excess time and muscular effort needed to actively bring the fingers to a stop at the interface of a virtual object was factored into the control law governing the initiation of closure in hf-VE. Crucially, this control law remained applicable, albeit with different weights in hf-VE, despite the absence of terminal haptic feedback and potential perceptual differences.

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Method of virtual reality for early comprehensive rehabilitation of patients with acute stroke

Vestnik nevrologii, psihiatrii i nejrohirurgii (Bulletin of Neurology, Psychiatry and Neurosurgery) ◽

10.33920/med-01-2001-04 ◽

2020 ◽

pp. 39-45

Author(s):

N. Nozdryukhina ◽

E. Kabayeva ◽

E. Kirilyuk ◽

K. Tushova ◽

A. Karimov

Keyword(s):

Virtual Reality ◽

Literature Review ◽

Acute Stroke ◽

Functional Outcome ◽

Recovery Process ◽

Stroke Patients ◽

Post Stroke ◽

Stroke Disability ◽

Comprehensive Rehabilitation ◽

High Level

Despite significant advances in the treatment and rehabilitation of stroke, level of post-stroke disability remains at a fairly high level. Recent innovative developments in the rehabilitation of these patients provide good results in terms of functional outcome. One of such developments is method of virtual reality (VR), which affects not only the speed and volume of regaining movement, as well as coordination, but also normalizes the psycho-emotional background, increasing the motivation of patients to improve the recovery process. This article provides a literature review of the use of the VR method in the rehabilitation of post-stroke patients, neurophysiological aspects of recovery of lost functions using this method are considered.

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Stroke Telerehabilitation in Calabria: A Health Technology Assessment

Frontiers in Neurology ◽

10.3389/fneur.2021.777608 ◽

2022 ◽

Vol 12 ◽

Author(s):

Contrada Marianna ◽

Arcuri Francesco ◽

Tonin Paolo ◽

Pignolo Loris ◽

Mazza Tiziana ◽

...

Keyword(s):

Virtual Reality ◽

Low Income ◽

Cognitive Rehabilitation ◽

Low Income Countries ◽

Rehabilitation Services ◽

Stroke Patients ◽

Post Stroke ◽

Home Service ◽

Rehabilitation System ◽

Specialist Rehabilitation

Introduction: Telerehabilitation (TR) is defined as a model of home service for motor and cognitive rehabilitation, ensuring continuity of care over time. TR can replace the traditional face-to-face approach as an alternative method of delivering conventional rehabilitation and applies to situations where the patient is unable to reach rehabilitation facilities or for low-income countries where outcomes are particularly poor. For this reason, in this study, we sought to demonstrate the feasibility and utility of a well-known TR intervention on post-stroke patients living in one of the poorest indebted regions of Italy, where the delivery of rehabilitation services is inconsistent and not uniform.Materials and Methods: Nineteen patients (13 male/6 female; mean age: 61.1 ± 8.3 years) with a diagnosis of first-ever ischemic (n = 14) or hemorrhagic stroke (n = 5), who had been admitted to the intensive rehabilitation unit (IRU) of the Institute S. Anna (Crotone, Italy), were consecutively enrolled to participate in this study. After the discharge, they continued the motor treatment remotely by means of a home-rehabilitation system. The entire TR intervention was performed (online and offline) using the Virtual Reality Rehabilitation System (VRRS) (Khymeia, Italy). All patients received intensive TR five times a week for 12 consecutive weeks (60 sessions, each session lasting about 1h).Results: We found a significant motor recovery after TR protocol as measured by the Barthel Index (BI); Fugl-Meyer motor score (FM) and Motricity Index (MI) of the hemiplegic upper limbs.Conclusions: This was the first demonstration that a well-defined virtual reality TR tool promotes motor and functional recovery in post-stroke patients living in a low-income Italian region, such as Calabria, characterized by a paucity of specialist rehabilitation services.

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Virtual reality as a new tool for the rehabilitation of post-stroke patients with chronic aphasia: an exploratory study

Aphasiology ◽

10.1080/02687038.2021.1998882 ◽

2021 ◽

pp. 1-11

Author(s):

Rosaria De Luca ◽

Simona Leonardi ◽

Giuseppa Maresca ◽

Foti Cuzzola Marilena ◽

Desiree Latella ◽

...

Keyword(s):

Virtual Reality ◽

Exploratory Study ◽

Stroke Patients ◽

Post Stroke ◽

Chronic Aphasia

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Eye Gaze Correlates of Motor Impairment in VR Observation of Motor Actions

Methods of Information in Medicine ◽

10.3414/me14-01-0125 ◽

2016 ◽

Vol 55 (01) ◽

pp. 79-83 ◽

Cited By ~ 2

Author(s):

A. Vourvopoulos ◽

A. Bernardino ◽

i Bermúdez Badia ◽

J. Alves

Keyword(s):

Virtual Reality ◽

Smooth Pursuit ◽

Healthy Subjects ◽

Eye Gaze ◽

Action Observation ◽

Motor Impairment ◽

Motor Deficits ◽

Stroke Patients ◽

Motor Actions ◽

Healthy Participants

Summary Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Methodologies, Models and Algorithms for Patients Rehabilitation”. Objective: Identify eye gaze correlates of motor impairment in a virtual reality motor observation task in a study with healthy participants and stroke patients. Methods: Participants consisted of a group of healthy subjects (N = 20) and a group of stroke survivors (N = 10). Both groups were required to observe a simple reach-and-grab and place-and-release task in a virtual environment. Additionally, healthy subjects were required to observe the task in a normal condition and a constrained movement condition. Eye movements were recorded during the observation task for later analysis. Results: For healthy participants, results showed differences in gaze metrics when comparing the normal and arm-constrained conditions. Differences in gaze metrics were also found when comparing dominant and non-dominant arm for saccades and smooth pursuit events. For stroke patients, results showed longer smooth pursuit segments in action observation when observing the paretic arm, thus providing evidence that the affected circuitry may be activated for eye gaze control during observation of the simulated motor action. Conclusions: This study suggests that neural motor circuits are involved, at multiple levels, in observation of motor actions displayed in a virtual reality environment. Thus, eye tracking combined with action observation tasks in a virtual reality display can be used to monitor motor deficits derived from stroke, and consequently can also be used for re -habilitation of stroke patients.

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