scholarly journals Development of a Lightweight Prosthetic Hand for Patients with Amputated Fingers

2020 ◽  
Vol 10 (10) ◽  
pp. 3536 ◽  
Author(s):  
Wooseok Ryu ◽  
Youngjin Choi ◽  
Yong Je Choi ◽  
Sungon Lee
Keyword(s):  
Three Dimensional ◽  
Body Part ◽  
Limb Amputation ◽  
Prosthetic Hand ◽  
Design Concepts ◽  
Design Issue ◽  
Distal Interphalangeal ◽  
Strength And Stiffness ◽  
Prosthetic Finger ◽  
Electrical Components

Finger amputations are the most common upper limb amputation, and they occur approximately 100 times more often than hand amputations. We developed a prosthetic hand for amputees with a thumb and metacarpal. In this case of amputation, the installation of actuators and electrical components is difficult because space is considerably limited owing to the residual metacarpal. This design issue is solved by installing actuators vertically between finger modules and the mounting part where the electrical parts are embedded. With this design, the arrangement between the palm of the patient and the fingers of the prosthetic hand can be adjusted as well. Weight is also an especially important design issue in the development of a practical prosthetic hand because the patient perceives that weight. Most prosthetic hands are attached to the residual limb of the amputee by compressing the contact surface between the product and the amputated body part of the patient. Heavy weight causes users to feel discomfort and fatigue over extended periods of usage. In this study, all frames used in the proposed prosthetic hand were fabricated from nylon using multi-jet-fusion three-dimensional printing. As a result, the weight of the developed prosthetic hand was only 152.32 g but still had the desired strength and stiffness. Each prosthetic finger has four-degree-of-freedom. The distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints are coupled and driven by power from an actuator, which is transferred to each joint through the tendons. Adduction, abduction, and self-adaptive grasping motions were passively realized using linear and torsional springs. The prototype was fabricated based on these design concepts and functions, and its functionality was verified in experiments using diverse objects.

The connective tissue and ligaments of the distal interphalangeal joint: a review and investigation using ultra-high field 16.4 Tesla magnetic resonance imaging

2013 ◽  
Vol 39 (4) ◽  
pp. 398-404 ◽  
Author(s):  
D. Slattery ◽  
C. Aland ◽  
G. Durbridge ◽  
G. Cowin
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Connective Tissue ◽  
High Field ◽  
Three Dimensional ◽  
Interphalangeal Joint ◽  
Resonance Imaging ◽  
Distal Interphalangeal Joint ◽  
Ultra High Field ◽  
Distal Interphalangeal

This study reviews the literature on the anatomy of the connective tissues surrounding the distal interphalangeal joint and further characterizes the three-dimensional relationships of these structures with ultra-high field magnetic resonance imaging. Ten cadaver fingers, fixed in a solution of 5% agar and 4% formalin, were imaged utilising an ultrashield 16.4 Tesla ultra-high field magnetic resonance imaging, yielding a total of 4000 images. Images were analysed using Osirix™ (version 5.5.1 32 bit edition) for three-dimensional reconstruction. We found numerous conflicting descriptions of the connective tissue structures around the distal interphalangeal joint. Based upon our literature review and imaging studies we have defined precisely Cleland’s ligaments, the oblique proximal septum, Grayson’s ligaments, the dorsal plate, and the interosseous ligaments of the distal interphalangeal joint.

“I Wish I Could Have My Leg”: A Qualitative Study on the Experiences of Individuals With Lower Limb Amputation

2021 ◽  
pp. 105477382110477
Author(s):  
Cigdem Canbolat Seyman ◽  
Yeter Sinem Uzar Ozcetin
Keyword(s):  
Lower Limb ◽  
Qualitative Data ◽  
Body Part ◽  
Lower Limb Amputation ◽  
Limb Amputation ◽  
Design Data ◽  
Software Support ◽  
Permanent Disability ◽  
Phenomenological Design ◽  
Insight Into

Amputation is commonly regarded as a lifesaving procedure. However, the loss of a body part can lead to permanent disability that can impact patients physically, psychologically, and socially. The aim of this study was to describe and understand the perspectives of patients with lower limb amputation (LLA) about their condition. The study uses a descriptive phenomenological design. Data were collected from 12 patients. The researchers conducted interviews using semi-structured questions. MAXQDA was used for qualitative software support in managing the interview data. Data were transcribed. The participants were aged 61.3 ± 10.8 years. Three themes emerged from the qualitative data: (i) losing control over one’s own life, (ii) dreams versus the realities of life, and (iii) future perceptions. Most of the participants emphasized that they face undesirable experiences in their post-amputation lives. The findings of the present study provide novel insight into how individuals subjectively experience life after LLA.

scholarly journals CNN with Pose Segmentation for Suspicious Object Detection in MMW Security Images

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4974 ◽  
Author(s):  
Zhichao Meng ◽  
Man Zhang ◽  
Hongxian Wang
Keyword(s):  
Object Recognition ◽  
Object Detection ◽  
Binary Classification ◽  
Three Dimensional ◽  
Recognition Task ◽  
Body Part ◽  
The Body ◽  
Deep Cnn ◽  
Human Pose ◽  
Weak Shape

Millimeter-wave (MMW) imaging scanners can see through clothing to form a three-dimensional holographic image of the human body and suspicious objects, providing a harmless alternative for non-contacting searches in security check. Suspicious object detection in MMW images is challenging, since most of them are small, reflection-weak, shape, and reflection-diverse. Conventional detectors with artificial neural networks, like convolution neural network (CNN), usually take the problem of finding suspicious objects as an object recognition task, yielding difficulties in developing large-amount and complete sample sets of objects. In this paper, a new algorithm is developed using the human pose segmentation followed by the deep CNN detection. The algorithm is emphasized to learn the similarity with humans’ body clutter applied to training corresponding CNNs after the image segmentation base of the pose estimation. Moreover, the suspicious object recognition in the MMW image is converted to a binary classification task. Instead of recognizing all sorts of suspicious objects, the CNN detector determines whether the body part images present the abnormal patterns containing suspicious objects. The proposed algorithm that is based on CNN with the pose segmentation has concise configuration, but optimal performance in the suspicious object detection. Extensive experiments confirm the effectiveness and superiority of the proposal.

Research on the Application of Cellular Algorithm in 3D Modeling of Cartoon Characters

2014 ◽  
Vol 513-517 ◽  
pp. 1744-1747
Author(s):  
Feng Liu
Keyword(s):  
Design Method ◽  
Three Dimensional ◽  
Production Costs ◽  
3D Animation ◽  
Design Concepts ◽  
Three Dimensional Modeling ◽  
Modeling Software ◽  
High Production ◽  
Cartoon Characters ◽  
Time And Energy

The traditional design method of 3D animation modelings, by which can obtain attractive and precise 3D animation modelings, is to use three-dimensional modeling software such as Maya or 3D Max to draw directly. However, this method is faced with many problems, for instance, the lack of creativity, long design circle, high production costs, etc. For the problem of the lack of creativity, the reason is that animation designers are often subject to the limitation of the existing modelings and design concepts in the design process, therefore, they can not design creative modelings which are attractive and unforgettable enough. [For the problem of long design circle and high production costs, the reason is that although the 3D animation software are powerful, to skillfully master them not only requires users to have knowledge of computer technology and aesthetics at the same time, but also need a long learning process of modeling. Moreover, it takes the designers a lot of time and energy to design, draw and complete each modeling, and this will undoubtedly extend the design circle and increase the costs to some extent. Therefore, how to quickly and automatically generate creative 3D animation modelings has become a research focus of the present computer-aided creative design.

scholarly journals Experimental Study on a New Reinforcement Method for Multilayer Industrial Building’s Vibration

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Kaizhong Xie ◽  
Hongwei Wang ◽  
Jianxi Zhou ◽  
Xiao Luo ◽  
Miao Yue
Keyword(s):  
Natural Frequency ◽  
Three Dimensional ◽  
Element Model ◽  
Industrial Building ◽  
Test Results ◽  
Dimensional Finite Element ◽  
Vibration Experiment ◽  
Length Direction ◽  
Strength And Stiffness ◽  
Three Dimensional Finite Element

In order to study a new reinforcement method for multilayer (4 layers) industrial building’s vibration, firstly, a new reinforcement method using a short-pier shear wall was put forward. Secondly, an engineering example of a multilayer industrial building with abnormal vibration was introduced. A three-dimensional finite element model of multilayer industrial building was established, and field vibration test was carried out. Test results showed that abnormal vibration of industrial building was caused by resonance between machines and multilayer industrial building. Finally, multilayer industrial building was reinforced by a new reinforcement method, and vibration experiment was carried out after reinforcement. The results show that the new reinforcement method has a good reinforcement effect. Strength and stiffness of multilayer industrial building were obviously improved, and natural frequency of industrial building in the length direction increased from 2.45 Hz to 5.87 Hz, natural frequency of industrial building in the width direction increased from 2.94 Hz to 7.83 Hz, frequencies of machines and frequencies of multilayer industrial building were not in resonance range, acceleration and velocity vibration characteristics of multilayer industrial building were improved, which can provide reference for the reinforcement of multilayer industrial building with a similar structural configuration.

scholarly journals Flexion Angles of Finger Joints in Two-Finger Tip Pinching Using 3D Bone Models Constructed from X-Ray Computed Tomography (CT) Images

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Satoshi Shimawaki ◽  
Yoshiaki Nakamura ◽  
Masataka Nakabayashi ◽  
Hideharu Sugimoto
Keyword(s):  
Index Finger ◽  
Three Dimensional ◽  
High Mobility ◽  
Ct Images ◽  
Flexion Angle ◽  
Normal Hand ◽  
Distal Interphalangeal ◽  
X Ray Computed ◽  
Different Diameters ◽  
Finger Tip

The motion analysis of two-finger tip pinching using the thumb and index finger provides crucial data for designing the motion mechanism of electric prosthetic hands. The purpose of this study is to determine the joints that have high mobility during two-finger tip pinching by measuring the flexion angle of each joint. Ten Japanese men with normal hand were selected. CT images were obtained while the hands adopted the following four postures: a basic posture not pinching a cylinder, and three postures pinching wooden cylinders with different diameters (2, 10, and 30 mm). Three-dimensional bone models of the thumb and index finger were created using the CT images and used to measure the flexion angles of the joints. The flexion angles of the proximal interphalangeal and metacarpophalangeal joints of the index finger significantly decreased as the diameter of the cylinder increased. However, even when the diameter of the cylinder changed, the flexion angle of the distal interphalangeal joint of the index finger, and the flexion and rotation angles of all of the thumb joints did not change. When pinching objects of different sizes with a two-finger tip pinch, the posture of the thumb is fixed, and only the posture of the index finger changes. When designing the two-finger tip pinch motion for an electric prosthetic hand, it is sufficient to drive the joints of the index finger only.

scholarly journals The development of a quick-running prediction tool for the assessment of human injury owing to terrorist attack within crowded metropolitan environments

2011 ◽  
Vol 366 (1562) ◽  
pp. 127-143 ◽  
Author(s):  
Daniel J. Pope
Keyword(s):  
Terrorist Attack ◽  
Three Dimensional ◽  
Medical Personnel ◽  
Body Part ◽  
Mathematical Representation ◽  
List Type ◽  
Prediction Tool ◽  
Body Parts ◽  
Set Up ◽  
Human Injury

In the aftermath of the London ‘7/7’ attacks in 2005, UK government agencies required the development of a quick-running tool to predict the weapon and injury effects caused by the initiation of a person borne improvised explosive device (PBIED) within crowded metropolitan environments. This prediction tool, termed the HIP (human injury predictor) code, was intended to: — assist the security services to encourage favourable crowd distributions and densities within scenarios of ‘sensitivity’; — provide guidance to security engineers concerning the most effective location for protection systems; — inform rescue services as to where, in the case of such an event, individuals with particular injuries will be located; — assist in training medical personnel concerning the scope and types of injuries that would be sustained as a consequence of a particular attack; — assist response planners in determining the types of medical specialists (burns, traumatic amputations, lungs, etc.) required and thus identify the appropriate hospitals to receive the various casualty types. This document describes the algorithms used in the development of this tool, together with the pertinent underpinning physical processes. From its rudimentary beginnings as a simple spreadsheet, the HIP code now has a graphical user interface (GUI) that allows three-dimensional visualization of results and intuitive scenario set-up. The code is underpinned by algorithms that predict the pressure and momentum outputs produced by PBIEDs within open and confined environments, as well as the trajectories of shrapnel deliberately placed within the device to increase injurious effects. Further logic has been implemented to transpose these weapon effects into forms of human injury depending on where individuals are located relative to the PBIED. Each crowd member is subdivided into representative body parts, each of which is assigned an abbreviated injury score after a particular calculation cycle. The injury levels of each affected body part are then summated and a triage state assigned for each individual crowd member based on the criteria specified within the ‘injury scoring system’. To attain a comprehensive picture of a particular event, it is important that a number of simulations, using what is substantively the same scenario, are undertaken with natural variation being applied to the crowd distributions and the PBIED output. Accurate mathematical representation of such complex phenomena is challenging, particularly as the code must be quick-running to be of use to the stakeholder community. In addition to discussing the background and motivation for the algorithm and GUI development, this document also discusses the steps taken to validate the tool and the plans for further functionality implementation.

A three-dimensional finite element model for locally reinforced timber joints made with hollow dowel fasteners

2000 ◽  
Vol 27 (4) ◽  
pp. 785-797 ◽  
Author(s):  
Z W Guan ◽  
P D Rodd
Keyword(s):  
Finite Element ◽  
Failure Mode ◽  
Three Dimensional ◽  
Ductile Failure ◽  
Element Model ◽  
Premature Failure ◽  
Physical Test ◽  
Timber Joint ◽  
Strength And Stiffness ◽  
Three Dimensional Finite Element

Brittle premature failure caused by splitting parallel to the timber grain is a common failure mode in glulam joints made with solid dowel type fasteners. It is thought that this problem can be alleviated by using hollow steel dowels as the fasteners and reinforcing the timber locally in the area of the joint. In this way, by varying the wall thickness of the dowels and the thickness of the reinforcing members, a chosen combination of strength and stiffness should be attainable together with a ductile failure mode. In this paper, three-dimensional nonlinear finite element models are developed to simulate (i) the structural performance of a timber joint made with a single hollow steel dowel and (ii) a moment transmitting joint made with a number of the dowels, each type being locally reinforced by densified veneer wood. The models incorporate suitably defined elastoplasticity and orthotropic elasticity and also allow for large deformations of the joints as well as for frictional contact between the timber and the dowel. They are calibrated against physical test data from joints loaded to failure.Key words: glulam, densified veneer wood, resin injected, hollow dowel fastener, moment transmitting, ductile failure, finite element.

The Development and Research of the Three-Dimensional Simulation System of the Garments CAD

2012 ◽  
Vol 155-156 ◽  
pp. 157-161
Author(s):  
Li Na Yang
Keyword(s):  
Graphic Design ◽  
Computer Aided Design ◽  
Rapid Development ◽  
Three Dimensional ◽  
Simulation System ◽  
The Sustainable Development ◽  
Design Concepts ◽  
Dimensional Simulation ◽  
Aided Design ◽  
2D To 3D

The development and research of three-dimensional (3D) simulation system of the garments CAD (Computer Aided Design) will change the traditional graphic design concepts and design methods, which will develop from two-dimensional (2D) to 3D. It means to build a comprehensive calculating methodology for forming real garments simulation system on the computer. Combining with the advanced CAD technology and technical works of Chinese garments industry will greatly improve the level of the sustainable development and intelligentialization of the software, and will accelerate the technical upgrade of modern garments industry and push the rapid development of national economy.

The association between perceived density in minimum apartments and spatial openness index three-dimensional visual analysis

2016 ◽  
Vol 44 (4) ◽  
pp. 764-795 ◽  
Author(s):  
Dafna Fisher-Gewirtzman
Keyword(s):  
Interior Design ◽  
Visual Analysis ◽  
Three Dimensional ◽  
Visibility Analysis ◽  
Design Concepts ◽  
General Evaluation ◽  
Adequate Quality ◽  
Visual Privacy ◽  
City Centres ◽  
Measured Volume

Small apartments exist in dense cities worldwide. Developing adequate quality small apartments in city centres would strongly attract current demand. Analysis, predictive tools and design concepts regulated for better interior design and lower perceived density would provide residential environments with happier tenants. This research evaluates perceived density and visual privacy in alternative minimum apartments based on the spatial openness index three-dimensional visibility analysis, i.e. their accumulated three-dimensional visibility calculations. The compatibility of the spatial openness index concept as predicting perceived density in minimum apartments was examined and assessed. An empirical study was conducted using a virtual reality experiment in a controlled environment – An immersive three-dimensional visualisation laboratory1, with more than 100 subjects participated in the experiment. Significant relations were found between perceived density and visual privacy for all apartments (single and double story). The measured volume of visible space from the door viewpoint (the entrance to minimum apartments) and the perceived density evaluated there by participants, and a general evaluation for the apartment are strongly related for both (single and double story groups). Strong correlation was found between visibility measurements from the door and the ‘visual privacy’ at the sofa/bed. According to assessment results the spatial openness index three-dimensional visibility analysis can predict the perceived density of minimum apartments.

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