The measurement of three-dimensional hand motion by the use of V.T.R.

1982 ◽  
Author(s):  
Nobuo Miyashiro
Keyword(s):  
Three Dimensional ◽  
Hand Motion

scholarly journals A Three-dimensional Finger Motion Measurement System of a Thumb and an Index Finger Without a Calibration Process

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 756 ◽  
Author(s):  
Yeongyu Park ◽  
Joonbum Bae
Keyword(s):  
Index Finger ◽  
Three Dimensional ◽  
Length Change ◽  
Measuring Method ◽  
Finger Joint ◽  
Joint Angles ◽  
Calibration Process ◽  
Hand Motion ◽  
Wearable Systems ◽  
Cmc Joint

Various wearable systems have been investigated to measure hand motion, but some challenges remain. Many systems require a calibration process to map sensor signals to actual finger joint angles by the principle of measuring the length change of the finger, or bending sensors. Also, few studies have investigated how to measure thumb motion accurately using the wearable systems. This paper proposes an exoskeleton system with linear Hall sensors to measure three-dimensional hand motion without a calibration process. The calibration process is avoided by measuring finger joint angles through an absolute rotation measurement. A new wearing method with lower parts underneath the hand joints and rubber bands is proposed to fix the structure to the hand and adapt it for various hand sizes. As the thumb has a complex biomechanical feature at carpometacarpal (CMC) joint, a new measuring method of the CMC joint is proposed to directly calculate the orientation of the metacarpal. The prototype of the thumb and index finger was manufactured, and the performance was verified experimentally by using an optical motion capture system.

Real-Time Gesture Recognition for Controlling a Virtual Hand

2012 ◽  
Vol 463-464 ◽  
pp. 1147-1150 ◽  
Author(s):  
Constantin Catalin Moldovan ◽  
Ionel Staretu
Keyword(s):  
Virtual Environments ◽  
Real Time ◽  
Three Dimensional ◽  
Video Stream ◽  
Human Hand ◽  
Hand Motion ◽  
Virtual Hand ◽  
Hand Control ◽  
Hand Gesture Detection ◽  
Detection And Recognition

Object tracking in three dimensional environments is an area of research that has attracted a lot of attention lately, for its potential regarding the interaction between man and machine. Hand gesture detection and recognition, in real time, from video stream, plays a significant role in the human-computer interaction and, on the current digital image processing applications, this represent a difficult task. This paper aims to present a new method for human hand control in virtual environments, by eliminating the need of an external device currently used for hand motion capture and digitization. A first step in this direction would be the detection of human hand, followed by the detection of gestures and their use to control a virtual hand in a virtual environment.

Task Effects on Three-Dimensional Dynamic Postures during Seated Reaching Movements: An Investigative Scheme and Illustration

1997 ◽  
Vol 39 (4) ◽  
pp. 659-671 ◽  
Author(s):  
Xudong Zhang ◽  
Don B. Chaffin
Keyword(s):  
Three Dimensional ◽  
Movement Control ◽  
Reaching Movements ◽  
Motion Direction ◽  
Hand Motion ◽  
Movement Data ◽  
Task Effects ◽  
Posture Prediction ◽  
Distinctive Difference ◽  
The Relationship

In this paper we describe a new scheme for empirically investigating the effects of task factors on three-dimensional (3D) dynamic postures during seated reaching movements. The scheme relies on an underlying model that integrates two statistical procedures: (a) a regression description of the relationship between the time-varying hand location and postural angles to characterize the movement data and (b) a series of analyses of variance to test the hypothesized task effects using representative instantaneous postures. The use of this scheme is illustrated by an experiment that examines two generic task factors: hand motion direction and motion completion time. Results suggest that hand motion direction is a significant task factor in determining instantaneous postures, whereas a distinctive difference in the time to complete a motion does not appear to have a significant effect. We discuss the concept of an instantaneous posture and its utility in dynamic studies of movements, some insights into human reaching movement control strategy, and implications for the development of a 3D dynamic posture prediction model.

A finger skill transfer system using a multi-fingered haptic interface robot and a hand motion image

Robotica ◽  
2013 ◽  
Vol 31 (8) ◽  
pp. 1251-1261 ◽  
Author(s):  
Takahiro Endo ◽  
Mana Kobayashi ◽  
Haruhisa Kawasaki
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Haptic Interface ◽  
Fine Motor ◽  
Transfer System ◽  
Motor Tasks ◽  
Hand Motion ◽  
Fingertip Forces ◽  
Hand Image ◽  
Three Dimensional Space

SUMMARYThe teaching of how to exert fingertip forces and how to move the fingers is essential for transferring skill using the fingers to perform fine motor tasks. In this paper we accomplish the transfer of fingertip forces and positions in three-dimensional space by combining a multi-fingered haptic interface robot, which can measure and present the three-dimensional forces and positions at five fingertips, and an image display system that records a trainer's hand image and displays it to a trainee. Several experimental results show a high fingertip force and position transferability and the great potential of our proposed transfer system.

scholarly journals A Flexible and Highly Sensitive Pressure Sensor Based on AgNWs/NRLF for Hand Motion Monitoring

Nanomaterials ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 945 ◽  
Author(s):  
Yi Sun ◽  
Zhaoqun Du
Keyword(s):  
Silver Nanowires ◽  
Low Cost ◽  
Three Dimensional ◽  
Pressure Sensors ◽  
Natural Rubber Latex ◽  
Dip Coating ◽  
Electrical Signal ◽  
Environmental Friendliness ◽  
Hand Motion ◽  
Highly Sensitive

Flexible, highly sensitive, easy fabricating process, low-cost pressure sensors are the trend for flexible electronic devices. Inspired by the softness, comfortable, environmental friendliness and harmless of natural latex mattress, herein, we report an agile approach of constructing a flexible 3D-architectured conductive network by dip-coating silver nanowires (AgNWs) on the natural rubber latex foam (NRLF) substrate that provide the 3D micro-network structure as the skeleton. The variation of the contact transformed into the electrical signal among the conductive three-dimensional random networks during compressive deformation is the piezoresistive effect of AgNWs/NRLF pressure sensors. The resulting AgNWs/NRLF pressure sensors exhibit desirable electrical conductivity (0.45–0.50 S/m), excellent flexibility (58.57 kPa at 80% strain), good hydrophobicity (~128° at 5th dip-coated times) and outstanding repeatability. The AgNWs/NRLF sensors can be assembled on a glove to detect hand motion sensitively such as bending, touching and holding, show potential application such as artificial skin, human prostheses and health monitoring in multifunctional pressure sensors.

Task Effects on Three-Dimensional Dynamic Postures during Seated Reaching Movements: An Analysis Method and Illustration

1996 ◽  
Vol 40 (13) ◽  
pp. 594-598 ◽  
Author(s):  
Xudong Zhang ◽  
Don B. Chaffin
Keyword(s):  
Hand Movement ◽  
Three Dimensional ◽  
Reaching Movements ◽  
Movement Direction ◽  
Motion Direction ◽  
Hand Motion ◽  
Movement Data ◽  
Task Effects ◽  
Posture Prediction ◽  
The Relationship

This paper presents a new method to empirically investigate the effects of task factors on three-dimensional (3D) dynamic postures during seated reaching movements. The method relies on a statistical model in which the effects of hand location and those of various task factors on dynamic postures are distinguished. Two statistical procedures are incorporated: a regression description of the relationship between the time-varying hand location and postural profiles to compress the movement data, and a series of analyses of variance to test the hypothesized task effects using instantaneous postures with prescribed hand locations as dependent measures. The use of this method is illustrated by an experiment which examines two generic task factors: 1) hand movement direction, and 2) motion completion time. The results suggest that the hand motion direction is a significant task factor and should be included as an important attribute when describing or modeling instantaneous postures. It was also found that the time to complete a motion under a self-paced mode was significantly different from a motivated mode, but the time difference did not significantly affect instantaneous postures. The concept of an instantaneous posture and its usage in dynamic studies of movements are discussed. Some understanding of human postural control as well as the implications for developing a general dynamic posture prediction model also are presented.

Measurement of Reaching Kinematics and Prehensile Dexterity in Nonhuman Primates

2007 ◽  
Vol 98 (2) ◽  
pp. 1015-1029 ◽  
Author(s):  
Marc A. Pizzimenti ◽  
Warren G. Darling ◽  
Diane L. Rotella ◽  
David W. McNeal ◽  
James L. Herrick ◽  
...  
Keyword(s):  
Nonhuman Primates ◽  
Food Pellet ◽  
Three Dimensional ◽  
Fine Motor ◽  
Performance Score ◽  
Effective Measure ◽  
Hand Motion ◽  
New Device ◽  
And Performance ◽  
Temporal Measures

A modified “Klüver” or dexterity board was developed to assess fine control of hand and digit movements by nonhuman primates during the acquisition of small food pellets from wells of different diameter. The primary advantages of the new device over those used previously include standardized positioning of target food pellets and controlled testing of each hand without the need for restraints, thereby allowing the monkey to move freely about the cage. Three-dimensional video analysis of hand motion was used to provide measures of reaching accuracy and grip aperture, as well as temporal measures of reach duration and food-pellet manipulation. We also present a validated performance score based on these measures, which serves as an indicator of successful food-pellet retrieval. Tests in three monkeys show that the performance score is an effective measure with which to study fine motor control associated with learning and handedness. We also show that the device and performance scores are effective for differentiating the effects of localized injury to motor areas of the cerebral cortex.

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