Prediction of mechanical behavior of 3D bioprinted tissue-engineered scaffolds using finite element method (FEM) analysis

2020 ◽  
Vol 33 ◽  
pp. 101181 ◽  
Author(s):  
Anahita Ahmadi Soufivand ◽  
Nabiollah Abolfathi ◽  
Seyyed Ataollah Hashemi ◽  
Sang Jin Lee
2020 ◽  
Vol 10 (6) ◽  
pp. 2139
Author(s):  
Betsy D. M. Chaparro-Rico ◽  
Daniele Cafolla ◽  
Marco Ceccarelli ◽  
Eduardo Castillo-Castaneda

Patients with neurological or orthopedic lesions require assistance during therapies with repetitive movements. NURSE (cassiNo-qUeretaro uppeR-limb aSsistive dEvice) is an arm movement aid device for both right- and left-upper limb. The device has a big workspace to conduct physical therapy or training on individuals including kids and elderly individuals, of any age and size. This paper describes the mechanism design of NURSE and presents a numerical procedure for testing the mechanism feasibility that includes a kinematic, dynamic, and FEM (Finite Element Method) analysis. The kinematic demonstrated that a big workspace is available in the device to reproduce therapeutic movements. The dynamic analysis shows that commercial motors for low power consumption can achieve the needed displacement, acceleration, speed, and torque. Finite Element Method showed that the mechanism can afford the upper limb weight with light-bars for a tiny design. This work has led to the construction of a NURSE prototype with a light structure of 2.6 kg fitting into a box of 35 × 45 × 30 cm. The latter facilitates portability as well as rehabilitation at home with a proper follow-up. The prototype presented a repeatability of ±1.3 cm that has been considered satisfactory for a device having components manufactured with 3D rapid prototyping technology.


Author(s):  
Tatsuo Nishizawa ◽  
Tadashi Fukuda ◽  
Saburo Matsuno ◽  
Kenji Himeno

In the design of concrete pavement, curling stresses caused by the temperature difference between the top and bottom surfaces of the slab should be calculated at the transverse joint edge in some cases. However, no such equation has been developed in the past. Accordingly, a curling stress equation was developed based on stress analysis using the finite-element method (FEM). In this FEM analysis, a concrete pavement and its transverse joint were expressed by means of a thin plate–Winkler foundation model and a spring joint model, respectively. Multiregression analysis was applied to the results of the FEM numerical calculation and, consequently, a curling stress equation was obtained. After comparing the calculated results of the equation with curling stress equations developed in the past, it was confirmed that the equation was valid and practical.


2007 ◽  
Vol 336-338 ◽  
pp. 1531-1533
Author(s):  
Jian Qiang Qi ◽  
Yong Huang ◽  
Shi Xi Ouyang ◽  
Nan Li ◽  
Jiang Li ◽  
...  

By means of a finite element method model, the effects of property parameters of refractory on thermal stress of injection lance have been studied. The results show that the maximum thermal stress increases with the improvement of thermal conductivity and elastic modulus of refractory, while it decreases at first and then increases with the improvement of the coefficient of expansion of refractory.


2013 ◽  
Vol 586 ◽  
pp. 202-205 ◽  
Author(s):  
Milos Milosevic ◽  
Nenad Mitrovic ◽  
Vesna Miletić ◽  
Uroš Tatic ◽  
Andrea Ezdenci

Local polymerization stress occurs due to polymerization shrinkage of resin based composites adhesively bonded to tooth tissues. Shrinkage causes local displacements of cavity walls, with possible occurrence of micro-cracks in the enamel, dentin and/or material itself. In order to design a cavity for experimental testing of polymerization shrinkage of dental composites using 3D optical analysis, in this paper finite element method (FEM) was used to analyze numerical models with different cavity radiuses. 3D optical strain and displacement analysis of composite materials and cavity walls is limited by equipment sensitivity i.e. 0.01% for strain and 1 micron for displacement. This paper presents the development of 3D computer premolar models with varying cavity radiuses, and local stress, strain and displacement analysis using FEM. Model verification was performed by comparing obtained results with data from the scientific literature. Using the FEM analysis of local strains, displacements and stresses exerted on cavity walls, it was concluded that the model with 1 mm radius was optimal for experimental optical 3D displacement analysis.


1984 ◽  
Vol 106 (1) ◽  
pp. 130-136 ◽  
Author(s):  
W. T. Asbill ◽  
P. D. Pattillo ◽  
W. M. Rogers

The purpose of this investigation was to gain a better understanding into the mechanical behavior of the API 8 Round casing connection, when subjected to service loads of assembly interference, tension and internal pressure. The connection must provide both structural and sealing functions and these functions were evaluated by several methods. Part I discusses the methods of analysis, which include hand calculations using strength of materials, finite element method via unthreaded and threaded models, and experimental analysis using strain gages. Comparisons of all three methods are made for stresses and show that the finite element method accurately models connection behavior.


2012 ◽  
Vol 170-173 ◽  
pp. 1837-1841
Author(s):  
Qiu Hua Duan ◽  
Lu Feng Yang ◽  
Meng Lin Lou

This paper mainly uses finite element method (FEM) to research how the bent-height influence on dynamic characteristic, acceleration reaction, dynamic water pressure, dynamic stress reaction of the aqueduct-water coupling structure seismic performance. Through calculation and analysis some significant results were obtained.


Sign in / Sign up

Export Citation Format

Share Document