Design and Analysis of a Novel Lightweight, Energy Economic Powered Knee Orthotic Device

2019 ◽  
Vol 13 (3) ◽  
Author(s):  
Saikat Sahoo ◽  
Aditya Jain ◽  
Dilip Kumar Pratihar
Keyword(s):  
Knee Joint ◽  
Power Consumption ◽  
Three Dimensional ◽  
Fast Response ◽  
Design Parameters ◽  
Angular Deviation ◽  
Natural Behavior ◽  
Orthotic Device ◽  
3D Printed ◽  
Novel Design

The task of a powered knee orthotic device (PKOD) is to assist the knee joint so that its natural behavior can be restored. The key features of a PKOD that may help to regain such characteristics are low power consumption, fast response, compactness, and lightweight. This study proposes a novel design of PKOD, where we have focused on the betterment of the mentioned features with the help of a new mechanism, namely a four-bar controlled compliance actuator (FCCA). In FCCA, instead of using the widely used screw transmission mechanism, a four-bar mechanism is used to modify the joint's angular deviation and stiffness. The main advantages of using FCCA over other existing mechanisms are to reduce the power consumption by amplification of input motor torque and to achieve a faster response at the same time, and these are achieved by utilizing a simple four-bar mechanism. In the proposed design, FCCA controls both the stiffness of the artificial knee joint using a compliance mechanism as well as knee flexion with the help of a pulley arrangement. A three-dimensional (3D)-printed prototype of the proposed design has been developed, after optimizing the inherent design parameters. Simulation and experimental analysis are carried out in order to justify the performance of the proposed PKOD. The results have shown strong agreement with that obtained using analytical study and optimization. Moreover, the torque amplification is achieved, as desired.

scholarly journals Biomechanical Assessment of Design Parameters on a Self-Developed 3D-Printed Titanium-Alloy Reconstruction/Prosthetic Implant for Mandibular Segmental Osteotomy Defect

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 597
Author(s):  
Sheng-Ni Huang ◽  
Ming-You Shie ◽  
Yen-Wen Shen ◽  
Jui-Ting Hsu ◽  
Heng-Li Huang ◽  
...  
Keyword(s):  
Oral Cancer ◽  
Cortical Bone ◽  
Three Dimensional ◽  
Design Parameters ◽  
Mandibular Bone ◽  
Biomechanical Assessment ◽  
Metal Printing ◽  
Facial Area ◽  
3D Metal Printing ◽  
3D Printed

Patients with oral cancer often have to undergo the surgery for mandibular excision. Once the bone in the cancerous area is removed, not only the facial area but also chewing function of the patient is needed to be repaired by clinicians. In recent years, the rapid growth of three-dimensional (3D) metal printing technology has meant that higher-quality facial reconstructions are now possible, which could even restore chewing function. This study developed 3D-printed titanium (Ti)-alloy reconstruction implant for a prosthesis designed for mandibular segmental osteotomy defects, and 3D finite element (FE) analysis was conducted to evaluate its biomechanical performance. The analyzed parameters in the FE models were as follows: (1) two prosthesis designs, namely a prosthesis retaining the residual mandibular bone (for patients with mild oral cancer) and a prosthesis with complete mandibular resection (for patients with severe oral cancer); (2) two lengths of prosthesis, namely 20 and 25 mm; and (3) three thicknesses of prosthesis, namely 0.8, 1, and 1.5 mm. A 45° lateral bite force (100 N) was applied to the top of the prosthesis as the loading condition. The results revealed that for the two prosthesis designs, the prosthesis retaining the residual mandibular bone showed higher stress on the prosthesis and cortical bone compared with the prosthesis with complete mandibular resection. Regarding the two prosthesis lengths, no fixed trend of prosthesis stress was found, but stress in the cortical bone was relatively high for a prosthesis length of 20 mm compared with that of 25 mm. For the three prosthesis thicknesses, as the thickness of the prosthesis decreased, the stress in the prosthesis decreased but the stress in the cortical bone increased. These findings require confirmation in future clinical investigations.

scholarly journals Clinical application of multiple 3D-printed guide plates for precise reduction and fixation of comminuted patellar fractures

2020 ◽  
Vol 48 (11) ◽  
pp. 030006052097208
Author(s):  
Zhi-Sheng Long ◽  
Fei-Peng Gong ◽  
Xie-Ping Dong ◽  
Jing-Tang Li
Keyword(s):  
Knee Joint ◽  
Articular Surface ◽  
Good Condition ◽  
Three Dimensional ◽  
Operation Time ◽  
Left Knee ◽  
Preoperative Imaging ◽  
Anatomical Landmarks ◽  
3D Printed ◽  
Patellar Fractures

Because of the lack of anatomical landmarks during reduction of multiple articular surfaces and fragments in comminuted patellar fractures, loss of bone fragments or aggravation of soft tissue and ligament injuries readily occurs. In the present case, we used multiple three-dimensional (3D)-printed guide plates to reduce and fix a comminuted patellar fracture. A 22-year-old man was hospitalized for 2 days because of left knee joint pain and limited movement caused by a traffic accident. Preoperative imaging revealed a comminuted fracture of the left patella (type 34-C3 according to the AO/OTA classification). Throughout a 2-year follow-up, the patient remained in generally good condition with no significant limitation of his left knee joint activity. Application of multiple 3D-printed guide plates is a safe and effective auxiliary technique for the treatment of comminuted patellar fractures. This novel technique can shorten the operation time, reduce the number of fluoroscopic procedures, and ensure fracture healing and recovery of knee joint function through reliable reduction of the articular surface.

3D-printed programmable tensegrity for soft robotics

2020 ◽  
Vol 5 (45) ◽  
pp. eaay9024
Author(s):  
Hajun Lee ◽  
Yeonwoo Jang ◽  
Jun Kyu Choe ◽  
Suwoo Lee ◽  
Hyeonseo Song ◽  
...  
Keyword(s):  
Smart Materials ◽  
Structural Integrity ◽  
Three Dimensional ◽  
Structural Complexity ◽  
System Level ◽  
Design Parameters ◽  
Tensegrity Structures ◽  
Tensegrity Systems ◽  
3D Printed ◽  
3D Shapes

Tensegrity structures provide both structural integrity and flexibility through the combination of stiff struts and a network of flexible tendons. These structures exhibit useful properties: high stiffness-to-mass ratio, controllability, reliability, structural flexibility, and large deployment. The integration of smart materials into tensegrity structures would provide additional functionality and may improve existing properties. However, manufacturing approaches that generate multimaterial parts with intricate three-dimensional (3D) shapes suitable for such tensegrities are rare. Furthermore, the structural complexity of tensegrity systems fabricated through conventional means is generally limited because these systems often require manual assembly. Here, we report a simple approach to fabricate tensegrity structures made of smart materials using 3D printing combined with sacrificial molding. Tensegrity structures consisting of monolithic tendon networks based on smart materials supported by struts could be realized without an additional post-assembly process using our approach. By printing tensegrity with coordinated soft and stiff elements, we could use design parameters (such as geometry, topology, density, coordination number, and complexity) to program system-level mechanics in a soft structure. Last, we demonstrated a tensegrity robot capable of walking in any direction and several tensegrity actuators by leveraging smart tendons with magnetic functionality and the programmed mechanics of tensegrity structures. The physical realization of complex tensegrity metamaterials with programmable mechanical components can pave the way toward more algorithmic designs of 3D soft machines.

The Effects of a Functional Three‐dimensional (3D) Printed Knee Joint Simulator in Improving Anatomical Spatial Knowledge

2019 ◽  
Vol 12 (6) ◽  
pp. 610-618 ◽  
Author(s):  
Bohong Cai ◽  
Kanagasuntheram Rajendran ◽  
Boon Huat Bay ◽  
Jieying Lee ◽  
Ching‐Chiuan Yen
Keyword(s):  
Knee Joint ◽  
Three Dimensional ◽  
Spatial Knowledge ◽  
3D Printed

scholarly journals Architecture-Level Exploration of Alternative Interconnection Schemes Targeting 3D FPGAs: A Software-Supported Methodology

2008 ◽  
Vol 2008 ◽  
pp. 1-18 ◽  
Author(s):  
Kostas Siozios ◽  
Alexandros Bartzas ◽  
Dimitrios Soudris
Keyword(s):  
Power Consumption ◽  
Three Dimensional ◽  
Reconfigurable Architectures ◽  
Design Parameters ◽  
Design Framework ◽  
Vertical Interconnection ◽  
Utilization Ratio ◽  
The Impact ◽  
Frequency Power ◽  
Operation Frequency

In current reconfigurable architectures, the interconnection structures increasingly contribute more to the delay and power consumption. The demand for increased clock frequencies and logic density (smaller area footprint) makes the problem even more important. Three-dimensional (3D) architectures are able to alleviate this problem by accommodating a number of functional layers, each of which might be fabricated in different technology. However, the benefits of such integration technology have not been sufficiently explored yet. In this paper, we propose a software-supported methodology for exploring and evaluating alternative interconnection schemes for 3D FPGAs. In order to support the proposed methodology, three new CAD tools were developed (part of the 3D MEANDER Design Framework). During our exploration, we study the impact of vertical interconnection between functional layers in a number of design parameters. More specifically, the average gains in operation frequency, power consumption, and wirelength are 35%, 32%, and 13%, respectively, compared to existing 2D FPGAs with identical logic resources. Also, we achieve higher utilization ratio for the vertical interconnections compared to existing approaches by 8% for designing 3D FPGAs, leading to cheaper and more reliable devices.

Compositional Tuning of Negative Differential Resistance in Bulk Silver Iodide Memristor

2020 ◽  
Author(s):  
SMITA GAJANAN NAIK ◽  
Mohammad Hussain Kasim Rabinal
Keyword(s):  
Power Consumption ◽  
Negative Differential Resistance ◽  
Silver Iodide ◽  
Differential Resistance ◽  
Fast Response ◽  
Low Power Consumption ◽  
Switching Effect ◽  
Memory Switching ◽  
Bulk Silver ◽  
Emerging Memory

Electrical memory switching effect has received a great interest to develop emerging memory technology such as memristors. The high density, fast response, multi-bit storage and low power consumption are their...

Operational Model and its Validation with Drift Tests in Water Areas Around the Baltic Sea

1994 ◽  
Vol 29 (2-3) ◽  
pp. 293-308
Author(s):  
J. Koponen ◽  
M. Virtanen ◽  
H. Vepsä ◽  
E. Alasaarela
Keyword(s):  
Three Dimensional ◽  
Fast Response ◽  
Velocity Measurements ◽  
Short Term ◽  
Large Lakes ◽  
Operational Model ◽  
Water Currents ◽  
Emergency Situations ◽  
Sensitivity Tests ◽  
The Baltic

Abstract Three-dimensional (3-D) mathematical models of water currents, transport, mixing, reaction kinetic, and interactions with bottom and air have been used in Finland regularly since 1982 and applied to about 40 cases in large lakes, inland seas and their coastal waters. In each case, model validity has been carefully tested with available flow velocity measurements, tracer studies and water quality observations. For operational use, i.e., for spill combatting and sea rescue, the models need fast response, proven validity and illustrative visualization. In 1987-90, validated models were implemented for operational use at five sea areas along the Finnish coast. Further validation was obtained in model applications from nine documented or arranged cases and from seven emergency situations. Sensitivity tests supplement short-term validation. In the Bothnian Sea, it was nescessary to start the calculation of water currents three days prior to the start of the experiment to reduce initial inaccuracies and to make the coastal transport estimates meaningful.

Use of Three-dimensional Printing in the Development of Optimal Cardiac CT Scanning Protocols

2020 ◽  
Vol 16 (8) ◽  
pp. 967-977
Author(s):  
Zhonghua Sun
Keyword(s):  
Cardiovascular Disease ◽  
Cardiac Computed Tomography ◽  
Three Dimensional ◽  
Ct Scanning ◽  
Aortic Diseases ◽  
Clinical Value ◽  
Three Dimensional Printing ◽  
Doctor Patient Communication ◽  
Medical Education And Training ◽  
3D Printed

Three-dimensional (3D) printing is increasingly used in medical applications with most of the studies focusing on its applications in medical education and training, pre-surgical planning and simulation, and doctor-patient communication. An emerging area of utilising 3D printed models lies in the development of cardiac computed tomography (CT) protocols for visualisation and detection of cardiovascular disease. Specifically, 3D printed heart and cardiovascular models have shown potential value in the evaluation of coronary plaques and coronary stents, aortic diseases and detection of pulmonary embolism. This review article provides an overview of the clinical value of 3D printed models in these areas with regard to the development of optimal CT scanning protocols for both diagnostic evaluation of cardiovascular disease and reduction of radiation dose. The expected outcomes are to encourage further research towards this direction.

scholarly journals A Novel Approach for a Faster Prototyping of Winter Sport Equipment Using Digital Image Correlation and 3D Printing

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 125
Author(s):  
Martino Colonna ◽  
Benno Zingerle ◽  
Maria Federica Parisi ◽  
Claudio Gioia ◽  
Alessandro Speranzoni ◽  
...  
Keyword(s):  
3D Printing ◽  
Digital Image Correlation ◽  
Digital Image ◽  
Sport Activity ◽  
Image Correlation ◽  
Topological Optimization ◽  
Design Parameters ◽  
Sport Equipment ◽  
Novel Approach ◽  
3D Printed

The optimization of sport equipment parts requires considerable time and high costs due to the high complexity of the development process. For this reason, we have developed a novel approach to decrease the cost and time for the optimization of the design, which consists of producing a first prototype by 3D printing, applying the forces that normally acts during the sport activity using a test bench, and then measuring the local deformations using 3D digital image correlation (DIC). The design parameters are then modified by topological optimization and then DIC is performed again on the new 3D-printed modified part. The DIC analysis of 3D-printed parts has shown a good agreement with that of the injection-molded ones. The deformation measured with DIC are also well correlated with those provided by finite element method (FEM) analysis, and therefore DIC analysis proves to be a powerful tool to validate FEM models.

Investigation of the Static Behavior and Failure Mechanisms of a 3D Printed Bio-Based Sandwich with Auxetic Core

2020 ◽  
Vol 12 (05) ◽  
pp. 2050051
Author(s):  
Khawla Essassi ◽  
Jean-Luc Rebiere ◽  
Abderrahim El Mahi ◽  
Mohamed Amine Ben Souf ◽  
Anas Bouguecha ◽  
...  
Keyword(s):  
Failure Mechanisms ◽  
Three Dimensional ◽  
Acoustic Emissions ◽  
Shear Stiffness ◽  
Tensile Tests ◽  
Sandwich Composite ◽  
Static Behavior ◽  
Flax Fibers ◽  
Data Points ◽  
3D Printed

In this research contribution, the static behavior and failure mechanisms are developed for a three-dimensional (3D) printed dogbone, auxetic structure and sandwich composite using acoustic emissions (AEs). The skins, core and whole sandwich are manufactured using the same bio-based material which is polylactic acid reinforced with micro-flax fibers. Tensile tests are conducted on the skins and the core while bending tests are conducted on the sandwich composite. Those tests are carried out on four different auxetic densities in order to investigate their effect on the mechanical and damage properties of the materials. To monitor the invisible damage and damage propagation, a highly sensitive AE testing method is used. It is found that the sandwich with high core density displays advanced mechanical properties in terms of bending stiffness, shear stiffness, facing bending stress and core shear stress. In addition, the AE data points during testing present an amplitude range of 40–85[Formula: see text]dB that characterizes visible and invisible damage up to failure.

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