A Physics-based Virtual Reality Environment to Quantify Functional Performance of Upper-limb Prostheses

2019 ◽  
Author(s):  
Katy Odette ◽  
Qiushi Fu
Keyword(s):  
Virtual Reality ◽  
Upper Limb ◽  
Functional Performance ◽  
Virtual Reality Environment ◽  
Upper Limb Prostheses

scholarly journals Kinematic of the Position and Orientation Synchronization of the Posture of a n DoF Upper-Limb Exoskeleton with a Virtual Object in an Immersive Virtual Reality Environment

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1069
Author(s):  
Deyby Huamanchahua ◽  
Adriana Vargas-Martinez ◽  
Ricardo Ramirez-Mendoza
Keyword(s):  
Virtual Reality ◽  
Upper Limb ◽  
Human Performance ◽  
Early Stage ◽  
Inverse Kinematic ◽  
Virtual Object ◽  
Immersive Virtual Reality ◽  
Virtual Reality Environment ◽  
Upper Limb Exoskeleton ◽  
Position And Orientation

Exoskeletons are an external structural mechanism with joints and links that work in tandem with the user, which increases, reinforces, or restores human performance. Virtual Reality can be used to produce environments, in which the intensity of practice and feedback on performance can be manipulated to provide tailored motor training. Will it be possible to combine both technologies and have them synchronized to reach better performance? This paper consists of the kinematics analysis for the position and orientation synchronization between an n DoF upper-limb exoskeleton pose and a projected object in an immersive virtual reality environment using a VR headset. To achieve this goal, the exoskeletal mechanism is analyzed using Euler angles and the Pieper technique to obtain the equations that lead to its orientation, forward, and inverse kinematic models. This paper extends the author’s previous work by using an early stage upper-limb exoskeleton prototype for the synchronization process.

scholarly journals Assessment of body-powered upper limb prostheses by able-bodied subjects, using the Box and Blocks Test and the Nine-Hole Peg Test

2014 ◽  
Vol 40 (1) ◽  
pp. 109-116 ◽  
Author(s):  
Liz Haverkate ◽  
Gerwin Smit ◽  
Dick H Plettenburg
Keyword(s):  
Study Design ◽  
Upper Limb ◽  
Clinical Relevance ◽  
Functional Performance ◽  
Reference Value ◽  
Functional Tests ◽  
Second Best ◽  
Terminal Device ◽  
Upper Limb Prostheses ◽  
Nine Hole Peg Test

Background: The functional performance of currently available body-powered prostheses is unknown. Objective: The goal of this study was to objectively assess and compare the functional performance of three commonly used body-powered upper limb terminal devices. Study design: Experimental trial. Methods: A total of 21 able-bodied subjects ( n = 21, age = 22 ± 2) tested three different terminal devices: TRS voluntary closing Hook Grip 2S, Otto Bock voluntary opening hand and Hosmer Model 5XA hook, using a prosthesis simulator. All subjects used each terminal device nine times in two functional tests: the Nine-Hole Peg Test and the Box and Blocks Test. Results: Significant differences were found between the different terminal devices and their scores on the Nine-Hole Peg Test and the Box and Blocks Test. The Hosmer hook scored best in both tests. The TRS Hook Grip 2S scored second best. The Otto Bock hand showed the lowest scores. Conclusion: This study is a first step in the comparison of functional performances of body-powered prostheses. The data can be used as a reference value, to assess the performance of a terminal device or an amputee. Clinical relevance The measured scores enable the comparison of the performance of a prosthesis user and his or her terminal device relative to standard scores.

scholarly journals Fatigue, induced via repetitive upper-limb motor tasks, influences trunk and shoulder kinematics during an upper limb reaching task in a virtual reality environment

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249403
Author(s):  
Frédérique Dupuis ◽  
Gisela Sole ◽  
Craig Wassinger ◽  
Mathieu Bielmann ◽  
Laurent J. Bouyer ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Upper Limb ◽  
Movement Speed ◽  
Electromyographic Activity ◽  
Virtual Reality Environment ◽  
Accuracy Improvement ◽  
Reaching Task ◽  
Fatigue Protocol ◽  
Time Interaction ◽  
Speed And Accuracy

Background Efficient shoulder movement depends on the ability of central nervous system to integrate sensory information and to create an appropriate motor command. Various daily encountered factors can potentially compromise the execution of the command, such as fatigue. This study explored how fatigue influences shoulder movements during upper limb reaching. Methods Forty healthy participants were randomly assigned to one of two groups: Control or Fatigue Group. All participants completed an upper limb reaching task at baseline and post-experimental, during which they reached four targets located at 90° of shoulder abduction, 90° external rotation at 90° abduction, 120° scaption, and 120° flexion in a virtual reality environment. Following the baseline phase, the Fatigue Group completed a shoulder fatigue protocol, while Controls took a 10-minute break. Thereafter, the reaching task was repeated. Upper limb kinematic (joint angles and excursions) and spatiotemporal (speed and accuracy) data were collected during the reaching task. Electromyographic activity of the anterior and middle deltoids were also collected to characterize fatigue. Two-way repeated-measures ANOVA were performed to determine the effects of Time, Group and of the interaction between these factors. Results The Fatigue group showed decreased mean median power frequency and increased electromyographic amplitudes of the anterior deltoid (p < 0.05) following the fatigue protocol. Less glenohumeral elevation, increased trunk flexion and rotation and sternoclavicular elevation were also observed in the Fatigue group (Group x Time interaction, p < 0.05). The Control group improved their movement speed and accuracy in post-experimental phase, while the Fatigue group showed a decrease of movement speed and no accuracy improvement (Group x Time interaction, p < 0.05). Conclusion In a fatigued state, changes in movement strategy were observed during the reaching task, including increased trunk and sternoclavicular movements and less glenohumeral movement. Performance was altered as shown by the lack of accuracy improvement over time and a decrease in movement speed in the Fatigue group.

scholarly journals Virtual Reality Environment with Haptic Feedback Thimble for Post Spinal Cord Injury Upper-Limb Rehabilitation

2021 ◽  
Vol 11 (6) ◽  
pp. 2476
Author(s):  
Álvaro Gutiérrez ◽  
Nicola Farella ◽  
Ángel Gil-Agudo ◽  
Ana de los Reyes Guzmán
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Virtual Reality ◽  
Upper Limb ◽  
Haptic Feedback ◽  
Cervical Spinal Cord ◽  
Virtual Reality Environment ◽  
Upper Limb Rehabilitation ◽  
Cord Injury ◽  
Limb Rehabilitation

Cervical spinal cord injury is damage to the spinal cord that causes temporary or permanent changes in body functions below the site of the injury. In particular, the impairment of the upper limbs limits the patient’s autonomy in the execution of activities of daily living. This paper illustrates the use of a low-cost robot with a virtual reality platform for upper limb rehabilitation of cervical spinal cord injury patients. Vibration and pressure haptic feedback sensations are provided thanks to a custom-made thimble feedback device. The virtual reality platform consists of three different virtual rehabilitation games developed in Unity. They provide the user with the opportunity to interact with the virtual scene using free hands thanks to the data collected by a hand tracking system. During the therapy session, quantitative data about the motor performance are collected. Each virtual reality environment can be modified in settings according to the patients’ needs. A proof of concept was performed with both healthy subjects and spinal cord injured patients to evaluate the platform and its usability. The data saved during the sessions are analyzed to validate the importance of haptic feedback and stored both for patients and therapists to control the performance and the recovery process.

Top-Down Processing and Visual Reorientation Illusions in a Virtual Reality Environment

2004 ◽  
Vol 63 (3) ◽  
pp. 143-149 ◽  
Author(s):  
Fred W. Mast ◽  
Charles M. Oman
Keyword(s):  
Virtual Reality ◽  
Visual Processing ◽  
Line Length ◽  
Perceptual Cues ◽  
Virtual Reality Environment ◽  
Top Down ◽  
Test Conditions ◽  
The Subject ◽  
Processing Mechanisms

The role of top-down processing on the horizontal-vertical line length illusion was examined by means of an ambiguous room with dual visual verticals. In one of the test conditions, the subjects were cued to one of the two verticals and were instructed to cognitively reassign the apparent vertical to the cued orientation. When they have mentally adjusted their perception, two lines in a plus sign configuration appeared and the subjects had to evaluate which line was longer. The results showed that the line length appeared longer when it was aligned with the direction of the vertical currently perceived by the subject. This study provides a demonstration that top-down processing influences lower level visual processing mechanisms. In another test condition, the subjects had all perceptual cues available and the influence was even stronger.

The Next Generation of Upper-Limb Prostheses, 1994

1994 ◽  
Author(s):  
William H. Donovan ◽  
◽  
Diane J. Atkins ◽  
Denise C. Y. Heard
Keyword(s):  
Upper Limb ◽  
Next Generation ◽  
Upper Limb Prostheses
Sign in / Sign up

Export Citation Format

Share Document