Design and operation of a tripod walking robot via dynamics simulation

Robotica ◽  
2010 ◽  
Vol 29 (5) ◽  
pp. 733-743 ◽  
Author(s):  
Conghui Liang ◽  
Hao Gu ◽  
Marco Ceccarelli ◽  
Giuseppe Carbone
Keyword(s):  
Mechanical Design ◽  
Low Cost ◽  
Three Dimensional ◽  
The Body ◽  
Dynamics Simulation ◽  
Walking Ability ◽  
Walking Robot ◽  
Three Dimensional Model ◽  
Software Environment ◽  
Leg Mechanisms

SUMMARYA mechanical design and dynamics walking simulation of a novel tripod walking robot are presented in this paper. The tripod walking robot consists of three 1-degree-of-freedom (DOF) Chebyshev–Pantograph leg mechanisms with linkage architecture. A balancing mechanism is mounted on the body of the tripod walking robot to adjust its center of gravity (COG) during walking for balancing purpose. A statically stable tripod walking gait is performed by synchronizing the motions of the three leg mechanisms and the balancing mechanism. A three-dimensional model has been elaborated in SolidWorks® engineering software environment for a characterization of a feasible mechanical design. Dynamics simulation has been carried out in the MSC.ADAMS® environment with the aim to characterize and to evaluate the dynamic walking performances of the proposed design with low-cost easy-operation features. Simulation results show that the proposed tripod walking robot with proper input torques, gives limited reaction forces at the linkage joints, and a practical feasible walking ability on a flatten ground.

scholarly journals Application of the finite element method to the design of an ankle orthosis

2021 ◽  
Vol 2130 (1) ◽  
pp. 012013
Author(s):  
D Stefańczak ◽  
J Gajewski ◽  
M Rogala
Keyword(s):  
Finite Element ◽  
Low Cost ◽  
Three Dimensional ◽  
Fem Analysis ◽  
Body Part ◽  
The Body ◽  
Design Stage ◽  
Mechanical Resistance ◽  
Three Dimensional Model ◽  
Element Analysis

Abstract AFO (Ankle-Foot Orthosis), which covers the ankle and foot, protects and supports the ankle joint as well as the structures around it. It contributes to the maintenance of the correct gait cycle. Owing to orthoses, the functional capacity of the body part is significantly improved, and so is the quality of life for the user. Personalized orthoses, which are adapted to the anatomy of the user, are more and more often produced by the additive methods. The use of 3D printing for the manufacturing medical devices is becoming increasingly common due to the low cost of the whole process, short production time and the possibility of the product personalization. One of the stages in manufacturing AFOs with the additive method is to create a three-dimensional model of the orthosis in CAD software. Finite element analysis was performed to assess the mechanical properties of the orthosis. The influence of geometry and the materials used were investigated with FEM analysis software. As a result of structural analysis during the design stage, the assessment of the medical device in terms of its durability and mechanical resistance without putting the user at risk is possible. On the basis of the obtained results, the structure strength was compared.

Three-dimensional model and molecular dynamics simulation of the active site of the self-splicing intervening sequence of the bacteriophage T4 nrdB messenger RNA

Biochemistry ◽  
1990 ◽  
Vol 29 (45) ◽  
pp. 10317-10322 ◽  
Author(s):  
Lennart Nilsson ◽  
Agneta Aahgren-Staalhandske ◽  
Ann Sofie Sjoegren ◽  
Solveig Hahne ◽  
Britt Marie Sjoeberg
Keyword(s):  
Molecular Dynamics ◽  
Active Site ◽  
Messenger Rna ◽  
Bacteriophage T4 ◽  
Three Dimensional ◽  
The Self ◽  
Dynamics Simulation ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Self Splicing

scholarly journals IMPROVING UAV TELEMETRY POSITIONING FOR DIRECT PHOTOGRAMMETRY

2021 ◽  
Vol XLIII-B2-2021 ◽  
pp. 61-68
Author(s):  
L. Rossi ◽  
F. Ioli ◽  
E. Capizzi ◽  
L. Pinto ◽  
M. Reguzzoni
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Control Points ◽  
Three Dimensional Model ◽  
Commercial Software ◽  
Ground Control Points ◽  
Lower Accuracy ◽  
Least Squares Adjustment ◽  
Gnss Receivers

Abstract. A fundamental step of UAV photogrammetric processes is to collect Ground Control Points (GCPs) by means of geodetic-quality GNSS receivers or total stations, thus obtaining an absolutely oriented model with a centimetric accuracy. This procedure is usually time-consuming, expensive and potentially dangerous for operators who sometimes need to reach inaccessible areas. UAVs equipped with low-cost GNSS/IMU sensors can provide information about position and attitude of the images. This telemetry information is not enough for a photogrammetric restitution with a centimetric accuracy, but it can be usefully exploited when a lower accuracy is required. The algorithm proposed in this paper aims at improving the quality of this information, in order to introduce it into a direct-photogrammetric process, without collecting GCPs. In particular, the estimation of an optimal trajectory is obtained by combining the camera positions derived from UAV telemetry and from the relative orientation of the acquired images, by means of a least squares adjustment. Then, the resulting trajectory is used as a direct observation of the camera positions into a commercial software, thus replacing the information of GCPs. The algorithm has been tested on different datasets, comparing the classical photogrammetric solution (with GCPs) with the proposed one. These case-studies showed that using the improved trajectory as input to the commercial software (without GCPs) the reconstruction of the three-dimensional model can be improved with respect to the solution computed by using the UAV raw telemetry only.

Dynamic Simulation Analysis of the Crane Hoisting Process Based on Adams

2014 ◽  
Vol 940 ◽  
pp. 132-135 ◽  
Author(s):  
Yi Fan Zhao ◽  
Ling Sha ◽  
Yi Zhu
Keyword(s):  
Dynamic Simulation ◽  
Simulation Analysis ◽  
Three Dimensional ◽  
Wire Rope ◽  
Dynamics Simulation ◽  
Dimensional Model ◽  
Analysis Model ◽  
Three Dimensional Model ◽  
Adams Software ◽  
Simulation Results

Established the dynamics simulation analysis model of crane hoisting mechanism based on the theory of dynamics in Adams software, and then through the three dimensional model of lifting mechanism dynamics entities, the constraints, load, drive can be added, the motion law can be defined to simulation analysis the change of the force of wire rope, the change of displacement, velocity and acceleration of lifting weight in the lifting process. On the basis of the simulation results, it can make a great improvement for the structure of crane and provide a meaningful theoretical reference for the hoisting machinery innovation design.

Three-dimensional modelling of wheelchair contrived with lower limb exoskeleton for right hemiplegic dysfunction

2020 ◽  
Vol 234 (7) ◽  
pp. 651-659
Author(s):  
AN Nithyaa ◽  
S Poonguzhali ◽  
N Vigneshwari
Keyword(s):  
Lower Limb ◽  
Computer Aided Design ◽  
Age Groups ◽  
Three Dimensional ◽  
The Body ◽  
Three Dimensional Model ◽  
Design Quality ◽  
Lower Limb Exoskeleton ◽  
Repeated Exercise ◽  
Aided Design

Hemiplegia is a type of paralysis that affects one side of the body due to stroke, characterizing severe weakness or rigid movement. Many people of different age groups are affected by this condition which cannot be completely cured but can be minimized through proper physiotherapy. A continuous and repeated exercise has to be given to the hemiplegic subjects to regain their motor function. To serve this purpose, a three-dimensional model of wheelchair contrived with lower limb exoskeleton is designed and motion analysis is done using SolidWorks. This virtual model of the object is created with the assistance of computer-aided design software. Professionals can be able to do the experiment on what-if scenarios with their three-dimensional designs, which helps to validate their devices and identify any snags with design quality. The pattern of behaviour of lower limb exoskeleton is predicted using SimMechanics in MATLAB.

Design of Bilateral Automatic Window Cleaning Device Based on Solid Edge

2014 ◽  
Vol 662 ◽  
pp. 183-186
Author(s):  
Guo Lei Xu ◽  
Tao Wu
Keyword(s):  
Simple Structure ◽  
High Efficiency ◽  
Simulation Analysis ◽  
Low Cost ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Model And Simulation ◽  
Cleaning Device ◽  
Solid Edge

This paper introduces an easy-sided automatic window cleaning device, which uses Solid Edge software to design three-dimensional model and simulation analysis of the structure. Contrasted with the function of existing products, this design has such advantages as simple structure, low cost, high efficiency, good effects and so on.

AFM-Based Nanoscratching: A 3D Molecular Dynamics Simulation With Experimental Verification

2014 ◽  
Author(s):  
Rapeepan Promyoo ◽  
Hazim El-Mounayri ◽  
Kody Varahramyan
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Md Simulation ◽  
Three Dimensional ◽  
Dynamics Simulation ◽  
Dimensional Model ◽  
Gold Substrate ◽  
Three Dimensional Model ◽  
Friction Forces ◽  
Defect Mechanism

In this paper, a developed three-dimensional model for AFM-based nanomachining is applied to study mechanical scratching at the nanoscale. The correlation between the scratching conditions, including applied force, scratching depth, and distant between any two scratched grooves, and the defect mechanism in the substrate/workpiece is investigated. The simulations of nanoscratching process are performed on different crystal orientations of single-crystal gold substrate, Au(100), Au(110), and Au(111). The material deformation and groove geometry are extracted from the final locations of atoms, which are displaced by the rigid indenter. The simulation also allows for the prediction of normal and friction forces at the interface between the indenter and substrate. An AFM is used to conduct actual scratching at the nanoscale, and provide measurements to which the MD simulation predictions are compared. The predicted forces obtained from MD simulation compares qualitatively with the experimental results.

Research of Automobile Modeling Design Method Based on Rapid Prototyping Technology

2013 ◽  
Vol 765-767 ◽  
pp. 71-74
Author(s):  
Wen Jiang Li ◽  
Pei Cheng Shi ◽  
Ping Xiao
Keyword(s):  
Rapid Prototyping ◽  
Design Method ◽  
Low Cost ◽  
Three Dimensional ◽  
The Body ◽  
Cad Model

According to the difficulties of current China's automobile modeling design,a kind of automobile modeling design method based on rapid prototyping technology was put forward.The method has characteristics that are fast modeling,low cost and easy to modify.The main difference from the current automobile modeling design method is to make use of color pictures to establish the bodys three-dimensional CAD model directly and with the use of rapid prototyping technology to make entity model of the body.

Ladle Transportation Car Frame Finite Element Analysis

2012 ◽  
Vol 591-593 ◽  
pp. 841-844
Author(s):  
Ping Tang ◽  
Chun Hua Pan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Optimization Design ◽  
Mechanical Design ◽  
Three Dimensional ◽  
Electrical Measurement ◽  
Stress And Strain ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
The Finite Element Analysis

Using the mechanical design of the software Solid works to established the 280 t LF the ladle furnace transportation car frame three dimensional model, and by using the finite element analysis of software Cosmos/works to static analysis for the frames, revealing that the frame of structure stress and strain distribution map of the frame, and also reveals that dangerous points and dangerous sections. Using resistance strain gauge to measure 280 t ladle transportation car frame, it is concluded that the frame of stress and strain distributions. Through the electrical measurement test the results were compared with finite element analysis results, further proof that the finite element analysis of the accuracy of the results provides theory basis for the optimization design of the frames.

Robot Guided Sheaths (RoGS) for Percutaneous Access to the Pediatric Kidney: Patient-Specific Design and Preliminary Results

2013 ◽  
Author(s):  
Tania K. Morimoto ◽  
Michael H. Hsieh ◽  
Allison M. Okamura
Keyword(s):  
Three Dimensional ◽  
The Body ◽  
Surrounding Tissue ◽  
Patient Specific ◽  
Three Dimensional Model ◽  
Specific Design ◽  
Surgical Access ◽  
Minimally Invasive Surgical ◽  
Area Of Interest ◽  
Ct Data

Robot-guided sheaths consisting of pre-curved tubes and steerable needles are proposed to provide surgical access to locations deep within the body. In comparison to current minimally invasive surgical robotic instruments, these sheaths are thinner, can move along more highly curved paths, and are potentially less expensive. This paper presents the patient-specific design of the pre-curved tube portion of a robot-guided sheath for access to a kidney stone; such a device could be used for delivery of an endoscope to fragment and remove the stone in a pediatric patient. First, feasible two-dimensional paths were determined considering workspace limitations, including avoidance of the ribs and lung, and minimizing collateral damage to surrounding tissue by leveraging the curvatures of the sheaths. Second, building on prior work in concentric-tube robot mechanics, the mechanical interaction of a two-element sheath was modeled and the resulting kinematics was demonstrated to achieve a feasible path in simulation. In addition, as a first step toward three-dimensional planning, patient-specific CT data was used to reconstruct a three-dimensional model of the area of interest.

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