scholarly journals Modeling Gait Patterns of a Patient with Orthopedic Injury Using an Exoskeleton

2020 ◽  
Vol 23 (6) ◽  
pp. 176-188
Author(s):  
S. F. Yatsun ◽  
Khalil Hamed Mohammed Hamood Al Manji ◽  
A. A. Postolny ◽  
A. S. Yatsun
Keyword(s):  
Control System ◽  
Ankle Joint ◽  
Research Work ◽  
Three Dimensional ◽  
Lower Limbs ◽  
Movement Trajectory ◽  
Joint Movement ◽  
Three Dimensional Model ◽  
Orthopedic Injury ◽  
Wide Range

Purpose of reseach. The paper describes the EXOLITE-REHAB rehabilitation robotic complex which makes it possible to do rehabilitation exercises of lower limbs of patients by performing leg lifting, verticalization, squats and other types of movement. In many countries, research work is underway to create devices that allow a person to move in space when the musculo-skeletal system is damaged.  Therefore, the purpose of this article is to study and set the basic regularities and algorithms based on mathematical models describing the controlled movement of the lower limbs exoskeleton by the example of modeling the movement of the exoskeleton's ankle joint.Methods. The key feature of the complex is the use of a follower-up control system that allows us to provide a prescribed movement of the human ankle joint with a high degree of accuracy in a wide range of parameters’ changes. Methods of mathematical modeling of the ankle joint movement are applied, taking into account their subsequent possible use in modeling the movement of exoskeleton links.Results. A kinematic setting of the ankle joint movement trajectory  is used in order to simulate the operation of a robotic system. In order to find the vector of generalized coordinates, the inverse kinematics problem is solved using the vector-matrix method with the application of Jacobian matrix. The results of numerical simulation show high convergence and adequacy of the proposed method.Conclusion. The article considers the method of using a follower-up control system that has a sufficient degree of accuracy of copying the trajectory. The results of modeling the follower-up control system of the EXOLITE-REHAB rehabilitation exoskeleton, working according to the developed algorithm, show that it is able to repeat the required trajectory with sufficient accuracy. In the future, we plan to study the system more deeply on a three-dimensional model with electric drives. 

Kinematics Simulation Analysis of a Kind of Pedal Rehabilitation Robot

2014 ◽  
Vol 602-605 ◽  
pp. 848-852
Author(s):  
Wen Long Wang ◽  
Ji Rong Wang
Keyword(s):  
Lower Limb ◽  
Simulation Analysis ◽  
Three Dimensional ◽  
Lower Limbs ◽  
Rehabilitation Robot ◽  
Movement Trajectory ◽  
Three Dimensional Model ◽  
Kinematics Simulation ◽  
Limb Rehabilitation ◽  
Lower Limb Rehabilitation

This paper describes the design of the gait mechanism of pedal lower limb rehabilitation robot based on people’s heel movement trajectory curve in the normal walking. It is established the kinematics mathematical model of a pedal lower limbs rehabilitation robot and the simplified three-dimensional model with Pro/e software, then it is simulated kinematics using ADAMS software. The simulation result is shown that this pedal lower limbs rehabilitation robot can achieve the expected rehabilitation exercise and run smoothly. Kinematics analysis and simulation of pedal rehabilitation robot is provided the necessary theoretical basis and parameters for the study of lower limb rehabilitation machinery.

Numerical Analysis on the Performance of the Solid Solar Particle Receiver With the Influence of Aerowindow

2008 ◽  
Author(s):  
Zhuoqi Chen ◽  
Yitung Chen ◽  
Taide Tan
Keyword(s):  
Solid Particle ◽  
Particle Temperature ◽  
Research Work ◽  
Three Dimensional ◽  
Fluid Phase ◽  
Injection Velocity ◽  
Average Particle ◽  
Three Dimensional Model ◽  
Particle Radiation ◽  
Solar Particle

In this research work, a three dimensional model of the solid solar particle receiver (SPR) with the influence of aerowindow is analyzed. The free-falling down particles will form a solid particle curtain and be directly heated up by the reflected concentrating solar energy which passes through the aperture of the cavity. The mass, momentum and energy exchange between the solid particle phase and gas fluid phase are simulated by the two-way coupling Euler-Lagrange method. A discrete ordinate radiative transfer method has been applied to study the coupling of radiative heat transfer and the falling particle curtain. The realizable κ-ε model is used in the investigation of turbulence flow. In order to predict the performance of the SPR, the aerodynamic behavior of the particles and thermal interaction, which include particle-particle radiation, particle-wall radiation, particle-air convection, and air-wall convection are analyzed and demonstrated in this work. All the investigation on the simulation model is focusing on optimizing the performance of the SPR. The parametric studies of the performance of the SPR with aerowindow are investigated under the different working conditions, such as air injection velocity, particle mass flow rate, and the efficiency of the SPR and exit average particle temperature are compared upon these conditions.

Analysis Method for Studying Groundwater under a Church

2016 ◽  
Vol 861 ◽  
pp. 263-270
Author(s):  
M. Eugenia Torner ◽  
Ángeles Mas ◽  
Carlos Lerma ◽  
Enrique Gil ◽  
Jose Vercher ◽  
...  
Keyword(s):  
Seventeenth Century ◽  
Ground Penetrating Radar ◽  
Research Work ◽  
Three Dimensional ◽  
Analysis Method ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Ground Penetrating ◽  
The Church ◽  
Main Entrance

The Church of Asunción of Llíria (Valencia, Spain) is one of the best examples of the Valencian Baroque of the seventeenth century. This research is based on the study of the building from an urban, historical, and especially, a constructive view. The location of this particular church is unique because it is embedded in a mountain. First, some excavations were made into the mountain before the construction of the church started. Thus, there is a slope between the main entrance of the church and the rear. This research work provides the analysis of the ground humidity throughout the Ground Penetrating Radar (GPR) technique. We have analysed the subsoil of the whole church by various cuts or paths. Longitudinal and transversal measurements allowed us to produce a three-dimensional model of the land on which the church stands. We have also analysed the homogeneity or heterogeneity of the subsoil in each area and the presence of certain ground water routes. The rising moisture has been analysed on the walls and pillars of the church. To this end, a moisture analyser has been employed to monitor the moisture content over a period of six months. With this information, it was possible to identify points that are systematically more humid.

scholarly journals BIM, realidad aumentada y técnicas holográficas aplicadas a la construcción = BIM, increased reality and holographic techniques applied to construction

2018 ◽  
Vol 4 (1) ◽  
pp. 27 ◽  
Author(s):  
Jaime Santamarta Martínez ◽  
Javier Mas Domínguez
Keyword(s):  
Augmented Reality ◽  
New Technologies ◽  
Three Dimensional ◽  
Pilot Project ◽  
Information Modeling ◽  
Three Dimensional Model ◽  
Modeling Methodology ◽  
Wide Range ◽  
Building Information ◽  
Nuevas Tecnologías

ResumenLa metodología BIM (Building Information Modelling), ampliamente implantada en el sector de la edificación y de la arquitectura, ha transformado la manera de desarrollar tanto los proyectos como las obras de construcción. Si bien la esencia de esta metodología se basa en la generación de un modelo tridimensional, la visualización de éste a través de dispositivos bidimensionales hace que la experiencia e interacción con el modelo no sea plena. Es por ello que la aparición en el mercado de nuevas tecnologías como la realidad virtual y la realidad aumentada, abren un amplio abanico de posibilidades ligadas al sector de la construcción. En este sentido, en Acciona Ingeniería se ha desarrollado un proyecto piloto en colaboración con Trimble y Microsoft donde a partir de un modelo BIM se ha creado una realidad aumentada basada en hologramas, que permitan recrear una simulación aplicada a la construcciónAbstractThe BIM (Building Information Modeling) methodology, widely implemented in the building and architecture sector, has transformed the way to develop both projects and construction works. Although the essence of this methodology is based on the generation of a three-dimensional model, the visualization of it through two-dimensional devices means that the experience and interaction with the model is not complete. That is why the appearance in the market of new technologies such as virtual reality and augmented reality, open a wide range of possibilities linked to the construction sector. In this sense, Acciona Engineering has developed a pilot project in collaboration with Trimble and Microsoft where, based on a BIM model, an augmented reality based on holograms has been created, allowing to recreate a simulation applied to construction

Evaluation of an approximate method for incorporating floating docks in harbor wave prediction models

2005 ◽  
Vol 32 (6) ◽  
pp. 1082-1092 ◽  
Author(s):  
Dongcheng Li ◽  
Vijay Panchang ◽  
Zhaoxiang Tang ◽  
Zeki Demirbilek ◽  
Jerry Ramsden
Keyword(s):  
Prediction Models ◽  
Three Dimensional ◽  
Wave Model ◽  
Three Dimensional Model ◽  
Transmission Coefficients ◽  
Mild Slope Equation ◽  
Wide Range ◽  
Floating Objects ◽  
Floating Breakwaters ◽  
D Model

Computer models based on the two-dimensional (2-D) elliptic mild-slope equation are nowadays routinely used in harbor engineering applications. However, structures like floating breakwaters and docks, which are often encountered in the modeling domain, render the problem for locally three-dimensional model and hence are problematic to incorporate in a 2-D model. Tsay and Liu (Applied Ocean Research. 1983. Vol 5(1): 30–37) proposed a highly simplified but approximate approach that does not violate the overall two dimensionality of the problem. The validity of their approach is examined in detail, and it is found that although their approximation provides results with the correct trend, the actual solutions deviate considerably from the theoretical solutions. We have developed correction factors that may be used to produce more reliable results using the framework of Tsay and Liu. Application of the resulting method to a harbor in Alaska shows that docks in the harbor distort the wave field considerably and create a reflective pattern that has the potential to affect navigation safety in some areas. A by-product of this paper consists of plots of transmission coefficients for waves propagating past rectangular and cylindrical floating objects of infinite extent for a wide range of conditions encountered in practice. Such transmission coefficients are at present readily available in the published literature for selected cases only.Key words: wave, model, mild slope, equation, floating breakwater, dock, marina, harbor.

Analysis of Conjugate Heat Transfer in a Three-Dimensional Microchannel Heat Sink for Cooling of Electronic Components

1999 ◽  
Author(s):  
Andrei G. Fedorov ◽  
Raymond Viskanta
Keyword(s):  
Heat Transfer ◽  
Heat Sink ◽  
Conjugate Heat Transfer ◽  
Stokes Equations ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Solid Substrate ◽  
Microchannel Heat Sink ◽  
Three Dimensional Model ◽  
Wide Range

Abstract A three-dimensional model is developed to investigate flow and conjugate heat transfer in the microchannel-based heat sink for electronic packaging applications. The incompressible laminar flow Navier-Stokes equations of motion as well as the energy conservation equations for the fluid and solid are employed as the governing model equations which are numerically solved using the generalized single-equation framework for solving conjugate problems. First, the theoretical model developed is validated by comparing the model predictions of the thermal resistance and the friction coefficient with available experimental data for a wide range of Reynolds numbers. Then, the parametric calculations are performed to investigate the effects of different working fluids, solid substrate materials and channel geometry on conjugate heat transfer in the microchannel heat sink. The bulk and wall temperature and heat flux distributions as well as the average heat transfer characteristics are reported and discussed. Important practical design recommendations are also provided regarding the cooling efficiency of the microchannel heat sink.

The Effect of Damage to the Lateral Collateral Ligaments on the Mechanical Characteristics of the Ankle Joint—An In-Vitro Study

1990 ◽  
Vol 112 (2) ◽  
pp. 129-137 ◽  
Author(s):  
S. Siegler ◽  
Jie Chen ◽  
C. D. Schneck
Keyword(s):  
Ankle Joint ◽  
Diagnostic Procedure ◽  
Mechanical Characteristics ◽  
Three Dimensional ◽  
Lower Limbs ◽  
Anterior Talofibular Ligament ◽  
Collateral Ligaments ◽  
Ligament Injuries ◽  
Calcaneofibular Ligament ◽  
Lateral Collateral Ligaments

Injuries to the lateral collateral ligaments of the ankle joint are among the most frequently occurring injuries at the lower limb. The present study was conducted for the purpose of establishing the basis for the development of a quantitative diagnostic procedure for such injuries. To achieve this goal, the effect of four types of ligament injuries on the three-dimensional mechanical characteristics of the ankle were investigated. These types of injuries consisted of: 1) isolated tear of the anterior talofibular ligament; 2) isolated tear of the calcaneofibular ligament; 3) isolated tear of the posterior talofibular ligament; and 4) combined tear of both the anterior talofibular ligament and the calcaneofibular ligament. The experiments were conducted on 31 amputated lower limbs and consisted of comparing the three-dimensional load-displacement and flexibility characteristics of the ankle joint prior to and following sectioning of selected ligaments. The experimental and analytical procedures used to derive these characteristics was developed previously by the authors [3, 24]. From the results of this study it was concluded that the three-dimensional flexibility characteristics of the ankle joint are strongly influenced by damage to the lateral collateral ligaments. Furthermore, it was found that each type of ligament injury produced unique and identifiably changes in the flexibility characteristics of the ankle. These unique changes, which are described in detail in this paper, can be used to discriminate between the different types of ligament injuries. Consequently, it was concluded that it is feasible to develop a quantitative diagnostic procedure for ankle ligament injuries based on the effect of the injury on the flexibility characteristics of the ankle.

Comparison of anatomical shoulder prostheses and the proximal humeri of Chinese people

2007 ◽  
Vol 221 (8) ◽  
pp. 921-927 ◽  
Author(s):  
L Zhang ◽  
B Yuan ◽  
C Wang ◽  
Z Liu
Keyword(s):  
Degenerative Change ◽  
Three Dimensional ◽  
Chinese People ◽  
Three Dimensional Model ◽  
Wide Range ◽  
Computed Tomography Scanning ◽  
Head Height ◽  
Large Bone ◽  
Range Of Variation ◽  
Anatomical Parameters

Reconstruction of normal anatomy is important to a successful proximal humeral arthroplasty, in which the surgeon needs to know multiple measured anatomical parameters during the surgery. Based on three-dimensional computed tomography scanning data, computer models of the proximal humeri of 180 Chinese people were built. They came from 77 males and 103 females; their ages ranged from 19 to 86 years. Anatomical parameters including the curvature diameter of the head, the head height, the inclination, and the retro-version were measured using the software in these three-dimensional proximal humerus models. The methodology was valid and the measured results showed marked variations in all those parameters. On average, the curvature diameter of the head was 44.6 mm, ranging from 36.4 to 55.5 mm. The head height was located at 16.7 ± 1.9 mm (minimum, 12.4 mm; maximum, 22.0 mm). The inclination angle ranged from 122.35° to 147.09° (mean, 132.4 ± 4.7°). The proximal humeral retroversion was found to be extremely variable, ranging from -4.71° to 52.46°, and has a mean of 21.11°. Then these measured results were compared with four commonly used anatomical prostheses. The wide range of variation in the normal values makes it difficult to restore anatomical characteristics individually. Thus, the use of an accurate three-dimensional model to guide surgery preoperatively can improve the outcome of some serious cases, such as gross degenerative change and large-bone-loss surgery.

scholarly journals Investigation of thermal conditions of nanosatellite optoelectronic telescopic module for different modes of operation

2019 ◽  
Vol 18 (2) ◽  
pp. 96-111 ◽  
Author(s):  
S. V. Tsaplin ◽  
S. A. Bolychev
Keyword(s):  
Control System ◽  
Three Dimensional ◽  
Thermal Conditions ◽  
Thermal Control ◽  
Operating Conditions ◽  
Temperature Fields ◽  
Three Dimensional Model ◽  
Optical Elements ◽  
Modes Of Operation ◽  
Thermal Control System

The problem of studying thermal conditions of the optoelectronic telescopic module of a nanosatellite under the influence of operating conditions is considered. To maintain optimal thermal conditions of the telescopic lens, a thermal control system based on electric heaters was chosen. Based on the three-dimensional model, the thermal regime of the lens is calculated taking into account the real operating conditions of the nanosatellite in its orbital motion. As a result of the calculation by the finite element method, the dynamics of the temperature fields of the lens was obtained for different modes of operation of the nanosatellite: access to the established thermal conditions, earth terrain survey in normal and extended modes. It is shown that in different modes of operation the thermal control system maintains a given temperature range of optical elements with moderate energy consumption and provides lens efficiency during the entire time of operation of the optoelectronic telescopic module of the nanosatellite.

Sign in / Sign up

Export Citation Format

Share Document