Effect of fruit and hand characteristics on thumb–index finger power-grasp stability during manual fruit sorting

2019 ◽  
Vol 157 ◽  
pp. 479-487 ◽  
Author(s):  
Xiaojing Chen ◽  
Zhiguo Li ◽  
Yuqing Wang ◽  
Jizhan Liu
Keyword(s):  
Index Finger ◽  
Grasp Stability ◽  
Power Grasp ◽  
Fruit Sorting

Heterodigital Free Flap of Index Finger Amputee for Coverage of the Long Finger Soft Tissue Defect

2013 ◽  
Vol 22 (2) ◽  
pp. 82-85 ◽  
Author(s):  
So-Min Hwang ◽  
Jang Hyuk Kim ◽  
Hong-Il Kim ◽  
Yong-Hui Jung ◽  
Hyung-Do Kim
Keyword(s):  
Soft Tissue ◽  
Free Flap ◽  
Index Finger ◽  
Soft Tissue Defect ◽  
Tissue Defect

An Enhanced Technique for Classification of Fruits using Shape Color and Texture Features

2017 ◽  
Vol 7 (7) ◽  
pp. 408
Author(s):  
Yashpal Jitarwal ◽  
Tabrej Ahamad Khan ◽  
Pawan Mangal
Keyword(s):  
Image Processing ◽  
Texture Features ◽  
Automatic Classification ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Advance Technique ◽  
Time Required ◽  
Fruit Sorting ◽  
Human Inspection

In earlier times fruits were sorted manually and it was very time consuming and laborious task. Human sorted the fruits of the basis of shape, size and color. Time taken by human to sort the fruits is very large therefore to reduce the time and to increase the accuracy, an automatic classification of fruits comes into existence.To improve this human inspection and reduce time required for fruit sorting an advance technique is developed that accepts information about fruits from their images, and is called as Image Processing Technique.

Context-dependent relationship in high-resolution micro-ECoG studies during finger movements

2020 ◽  
Vol 132 (5) ◽  
pp. 1358-1366
Author(s):  
Chao-Hung Kuo ◽  
Timothy M. Blakely ◽  
Jeremiah D. Wander ◽  
Devapratim Sarma ◽  
Jing Wu ◽  
...  
Keyword(s):  
High Resolution ◽  
Sensorimotor Cortex ◽  
Index Finger ◽  
Hand Movement ◽  
Cortical Activation ◽  
Hand Movements ◽  
Finger Movements ◽  
Thumb Movement ◽  
Neurosurgical Patients ◽  
The Relationship

OBJECTIVEThe activation of the sensorimotor cortex as measured by electrocorticographic (ECoG) signals has been correlated with contralateral hand movements in humans, as precisely as the level of individual digits. However, the relationship between individual and multiple synergistic finger movements and the neural signal as detected by ECoG has not been fully explored. The authors used intraoperative high-resolution micro-ECoG (µECoG) on the sensorimotor cortex to link neural signals to finger movements across several context-specific motor tasks.METHODSThree neurosurgical patients with cortical lesions over eloquent regions participated. During awake craniotomy, a sensorimotor cortex area of hand movement was localized by high-frequency responses measured by an 8 × 8 µECoG grid of 3-mm interelectrode spacing. Patients performed a flexion movement of the thumb or index finger, or a pinch movement of both, based on a visual cue. High-gamma (HG; 70–230 Hz) filtered µECoG was used to identify dominant electrodes associated with thumb and index movement. Hand movements were recorded by a dataglove simultaneously with µECoG recording.RESULTSIn all 3 patients, the electrodes controlling thumb and index finger movements were identifiable approximately 3–6-mm apart by the HG-filtered µECoG signal. For HG power of cortical activation measured with µECoG, the thumb and index signals in the pinch movement were similar to those observed during thumb-only and index-only movement, respectively (all p > 0.05). Index finger movements, measured by the dataglove joint angles, were similar in both the index-only and pinch movements (p > 0.05). However, despite similar activation across the conditions, markedly decreased thumb movement was observed in pinch relative to independent thumb-only movement (all p < 0.05).CONCLUSIONSHG-filtered µECoG signals effectively identify dominant regions associated with thumb and index finger movement. For pinch, the µECoG signal comprises a combination of the signals from individual thumb and index movements. However, while the relationship between the index finger joint angle and HG-filtered signal remains consistent between conditions, there is not a fixed relationship for thumb movement. Although the HG-filtered µECoG signal is similar in both thumb-only and pinch conditions, the actual thumb movement is markedly smaller in the pinch condition than in the thumb-only condition. This implies a nonlinear relationship between the cortical signal and the motor output for some, but importantly not all, movement types. This analysis provides insight into the tuning of the motor cortex toward specific types of motor behaviors.

Pseudosyndactylic Toe-to-Hand Transfer for Simultaneous Reconstruction of the Thumb and Index Finger

2003 ◽  
Vol 111 (1) ◽  
pp. 355-360
Author(s):  
Selçuk Işik ◽  
Mustafa Nişanci ◽  
Ergin Er ◽  
Haluk Duman
Keyword(s):  
Index Finger ◽  
Simultaneous Reconstruction

Visual and Tactile Information About Object-Curvature Control Fingertip Forces and Grasp Kinematics in Human Dexterous Manipulation

2000 ◽  
Vol 84 (6) ◽  
pp. 2984-2997 ◽  
Author(s):  
Per Jenmalm ◽  
Seth Dahlstedt ◽  
Roland S. Johansson
Keyword(s):  
Visual Processing ◽  
Visual Cues ◽  
Grip Force ◽  
Center Of Mass ◽  
Precision Grip ◽  
Sensory Information ◽  
Afferent Input ◽  
Dependent Manner ◽  
Tactile Sensibility ◽  
Grasp Stability

Most objects that we manipulate have curved surfaces. We have analyzed how subjects during a prototypical manipulatory task use visual and tactile sensory information for adapting fingertip actions to changes in object curvature. Subjects grasped an elongated object at one end using a precision grip and lifted it while instructed to keep it level. The principal load of the grasp was tangential torque due to the location of the center of mass of the object in relation to the horizontal grip axis joining the centers of the opposing grasp surfaces. The curvature strongly influenced the grip forces required to prevent rotational slips. Likewise the curvature influenced the rotational yield of the grasp that developed under the tangential torque load due to the viscoelastic properties of the fingertip pulps. Subjects scaled the grip forces parametrically with object curvature for grasp stability. Moreover in a curvature-dependent manner, subjects twisted the grasp around the grip axis by a radial flexion of the wrist to keep the desired object orientation despite the rotational yield. To adapt these fingertip actions to object curvature, subjects could use both vision and tactile sensibility integrated with predictive control. During combined blindfolding and digital anesthesia, however, the motor output failed to predict the consequences of the prevailing curvature. Subjects used vision to identify the curvature for efficient feedforward retrieval of grip force requirements before executing the motor commands. Digital anesthesia caused little impairment of grip force control when subjects had vision available, but the adaptation of the twist became delayed. Visual cues about the form of the grasp surface obtained before contact was used to scale the grip force, whereas the scaling of the twist depended on visual cues related to object movement. Thus subjects apparently relied on different visuomotor mechanisms for adaptation of grip force and grasp kinematics. In contrast, blindfolded subjects used tactile cues about the prevailing curvature obtained after contact with the object for feedforward adaptation of both grip force and twist. We conclude that humans use both vision and tactile sensibility for feedforward parametric adaptation of grip forces and grasp kinematics to object curvature. Normal control of the twist action, however, requires digital afferent input, and different visuomotor mechanisms support the control of the grasp twist and the grip force. This differential use of vision may have a bearing to the two-stream model of human visual processing.

scholarly journals Grasping Assisting Algorithm in Tele-Operated Robotic Gripper

2021 ◽  
Vol 11 (6) ◽  
pp. 2640
Author(s):  
Tomer Fine ◽  
Guy Zaidner ◽  
Amir Shapiro
Keyword(s):  
State Of The Art ◽  
Human Subjects ◽  
Quality Measures ◽  
Human Operator ◽  
Physical Presence ◽  
Complete State ◽  
The Future ◽  
Power Grasp ◽  
Grasp Quality

The involvement of Robots and automated machines in different industries has increased drastically in recent years. Part of this revolution is accomplishing tasks previously performed by humans with advanced robots, which would replace the entire human workforce in the future. In some industries the workers are required to complete different operations in hazardous or difficult environments. Operations like these could be replaced with the use of tele-operated systems that have the capability of grasping objects in their surroundings, thus abandoning the need for the physical presence of the human operator at the area while still allowing control. In this research our goal is to create an assisting system that would improve the grasping of a human operator using a tele-operated robotic gripper and arm, while advising the operator but not forcing a solution. For a given set of objects we computed the optimal grasp to be achieved by the gripper, based on two grasp quality measures of our choosing (namely power grasp and precision grasp). We then tested the performance of different human subjects who tried to grasp the different objects with the tele-operated system, while comparing their success to unassisted and assisted grasping. Our goal is to create an assisting algorithm that would compute optimal grasps and might be integrated into a complete, state-of-the-art tele-operated system.

scholarly journals Anosmia as a Screening Tool for COVID-19 Infection: A Prospective Cohort Study

2021 ◽  
pp. 1-6
Author(s):  
Esra AlHamadani ◽  
Sania Zia ◽  
Ali AlRahma ◽  
Firas AlNajjar
Keyword(s):  
Odds Ratio ◽  
Screening Tool ◽  
Index Finger ◽  
Upper Respiratory Tract ◽  
Chain Reaction ◽  
The Public ◽  
Single Center Study ◽  
Upper Respiratory ◽  
Polymerase Chain ◽  
Low Sensitivity

<b><i>Objectives:</i></b> Several studies promoted anosmia as a possible isolated symptom for coronavirus disease 2019 (COVID-19). No studies used feasible methods of smell testing that the public would use to address the accuracy of these claims. <b><i>Methods:</i></b> This is a single-center study conducted between April 2020 and June 2020. The sense of smell was tested in vitally stable suspected COVID-19 patients with no/mild upper respiratory tract infection symptoms prior to nasopharyngeal swabbing for reverse-transcriptase polymerase chain reaction. Patients were instructed to close their eyes. Each nostril was tested separately while the other was blocked with the patient’s index finger. Patients inhaled from 2 concealed vials (coffee and strawberry essence) consecutively, kept within 30 cm of the nostril for 60 s. Patients who could not identify both odors with both nostrils were recorded as “anosmia.” <b><i>Results:</i></b> Out of 346 eligible subjects, 43 had anosmia of which 26 (60%) tested COVID-19 positive. χ<sup>2</sup> test showed a <i>p</i> value &#x3c;0.001. The test showed a sensitivity of 30% (95% confidence interval [CI] 21%, 41%) and specificity 94% (95% CI 90%, 96%). Logistic regression revealed an odds ratio of 5.9 (95% CI 3.0, 12) <i>p</i> value &#x3c;0.001. <b><i>Conclusion:</i></b> Given the low sensitivity (30%) of this method in detecting COVID-19 infection, we conclude that this method is not a useful screening tool for COVID-19 infection. The moderate negative predictive value (80%) is nongeneralizable.

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