scholarly journals Typical configuration analysis of a modular reconfigurable cable-driven parallel robot

2019 ◽  
Vol 16 (2) ◽  
pp. 172988141983475 ◽  
Author(s):  
Tao Zhao ◽  
Bin Zi ◽  
Sen Qian ◽  
Zeqiang Yin ◽  
Dan Zhang
Keyword(s):  
Inverse Kinematics ◽  
Parallel Robot ◽  
Structure Design ◽  
Kinematics And Dynamics ◽  
Lagrange Method ◽  
Practical Applications ◽  
Task Requirements ◽  
Dynamics Models ◽  
Typical Configuration ◽  
And Control

To obtain better flexibility and multifunction in varying practical applications, several typical configurations of a modular reconfigurable cable-driven parallel robot are analyzed in this article. The spatial topology of the modular reconfigurable cable-driven parallel robot can be reconfigured by manually detaching or attaching the different number of modular branches as well as changing the connection points on the end-effector to satisfy diverse task requirements. The structure design of the modular reconfigurable cable-driven parallel robot is depicted in detail, including the design methodology, mechanical description, and control architecture. The inverse kinematics and dynamics of the modular reconfigurable cable-driven parallel robot considering diverse configurations are derived according to the vector closed rule and Lagrange method, respectively. The numerical simulation and related experiments of a typical configuration are achieved and analyzed. The results verify the effectiveness and feasibility of the inverse kinematics and dynamics models for the modular reconfigurable cable-driven parallel robot.

Dynamic Modeling of Overconstrained Parallel Robot

2013 ◽  
Vol 373-375 ◽  
pp. 34-37
Author(s):  
Jian Xin Yang ◽  
Zhen Tao Liu ◽  
Jian Wei Sun
Keyword(s):  
Dynamic Modeling ◽  
Virtual Work ◽  
Parallel Robot ◽  
Tree Structure ◽  
Kinematics And Dynamics ◽  
Dynamics Analysis ◽  
Forward Dynamics ◽  
Principle Of Virtual Work ◽  
Closed Form Solutions ◽  
Dynamics Models

The dynamic modeling method for parallel robot based on the principle of virtual work and equivalent tree structure is proposed by taking off the platform and the chains as well as degenerating parallel robot into a tree structure, the closed-form solutions for the inverse and forward dynamics models of parallel robot are derived. The method is applied on kinematics and dynamics analysis of a representative 3-RRR spherical parallel robot.

Modeling and Control of Winding Hybrid-Driven Based Cable-Parallel Manipulator

2013 ◽  
Vol 373-375 ◽  
pp. 111-115 ◽  
Author(s):  
Hui Hui Sun ◽  
Bin Zi ◽  
Sen Qian
Keyword(s):  
Fuzzy Control ◽  
Parallel Manipulator ◽  
Adaptive Fuzzy Control ◽  
Parallel Manipulators ◽  
Kinematics And Dynamics ◽  
Friction Compensation ◽  
Lagrange Method ◽  
Modeling And Control ◽  
Adaptive Fuzzy ◽  
And Control

This paper deals with modeling and adaptive fuzzy control of winding hybrid-driven cable parallel manipulator (WHDCPM). The WHDCPM has the advantages of both the traditional cable-parallel manipulator (CPM) and hybrid-driven based cable-parallel manipulator (HDCPM) since the hybrid-driven planar five-bar mechanism in HDCPM is replaced by winding hybrid-driven five-bar manipulator in WHDCPM. The physical architecture of WHDCPM is determined, and kinematics and dynamics of the cable parallel manipulators have been studied based on Lagrange method. The numerical simulation is demonstrated as an example with adaptive fuzzy control theory, and the diagrams of trajectory tracking, cable tension, friction compensation and motor torque are shown, respectively. The results demonstrate the feasibility and superiority of the WHDCPM.

Kinematics and Dynamics of a 3-CRU Spherical Parallel Robot

2007 ◽  
Author(s):  
Massimo Callegari ◽  
Alessandro Cammarata ◽  
Andrea Gabrielli ◽  
Rosario Sinatra
Keyword(s):  
Numerical Simulations ◽  
Closed Form ◽  
Parallel Robot ◽  
Kinematics And Dynamics ◽  
Mobility Analysis ◽  
Direct Dynamics ◽  
Pure Rotation ◽  
Moving Platform ◽  
Dynamics Models

This paper describes the kinematics and dynamics of a spherical parallel wrist called 3-CRU after the topology of its legs. After a mobility analysis showing the geometrical conditions that yield motions of pure rotation, its kinematics is worked out in closed-form for both position and velocity problems. Then inverse and direct dynamics models are developed and the latter is investigated by the use of the multibody NOC method. Seven bodies are considered by the models: two links for each one of the three legs and the moving platform, while inertial joints parameters have been neglected. Finally, numerical simulations are presented to validate the model. This architecture adopts kinematic pairs that make it suitable for being realized at a mini- or microscale. The Authors are presently developing the design of a robot based on such a concept.

Animal Pain Scales in Public Policy

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 41-50
Author(s):  
F. Barbara Orlans
Keyword(s):  
Public Policy ◽  
Animal Welfare ◽  
The United States ◽  
Pain Scale ◽  
Laboratory Animals ◽  
Practical Applications ◽  
Animal Pain ◽  
Pain Scales ◽  
History Of ◽  
And Control

Pain scales classify the severity of pain inflicted on laboratory animals from little or none up to severe. A pain scale as part of public policy serves beneficial purposes that promote animal welfare. It can be used to educate people about the two alternatives of refinement and replacement, and the need to reduce animal pain. Furthermore, a pain scale has practical applications: 1) in review procedures for animal welfare concerns; 2) in developing policies on the use of animals in education; and 3) as a basis for collecting national data on animal experimentation, so that meaningful data can be collected on trends in reduction and control in animal pain. So far, only a few countries (including Sweden, the Netherlands, Canada and New Zealand) have adopted pain scales as part of their public policy. Most countries, including the United States, have not yet done so. The history of the development and adoption of pain scales by various countries is described and the case is presented for wider adoption of a pain scale in countries not currently using one.

scholarly journals Engineering Ruthenium-Based Electrocatalysts for Effective Hydrogen Evolution Reaction

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Yingjie Yang ◽  
Yanhui Yu ◽  
Jing Li ◽  
Qingrong Chen ◽  
Yanlian Du ◽  
...  
Keyword(s):  
Hydrogen Evolution ◽  
Hydrogen Evolution Reaction ◽  
Rational Design ◽  
Energy System ◽  
Structure Design ◽  
Single Atom ◽  
Research Progress ◽  
Pure Hydrogen ◽  
Hydrogen Energy ◽  
Practical Applications

AbstractThe investigation of highly effective, durable, and cost-effective electrocatalysts for the hydrogen evolution reaction (HER) is a prerequisite for the upcoming hydrogen energy society. To establish a new hydrogen energy system and gradually replace the traditional fossil-based energy, electrochemical water-splitting is considered the most promising, environmentally friendly, and efficient way to produce pure hydrogen. Compared with the commonly used platinum (Pt)-based catalysts, ruthenium (Ru) is expected to be a good alternative because of its similar hydrogen bonding energy, lower water decomposition barrier, and considerably lower price. Analyzing and revealing the HER mechanisms, as well as identifying a rational design of Ru-based HER catalysts with desirable activity and stability is indispensable. In this review, the research progress on HER electrocatalysts and the relevant describing parameters for HER performance are briefly introduced. Moreover, four major strategies to improve the performance of Ru-based electrocatalysts, including electronic effect modulation, support engineering, structure design, and maximum utilization (single atom) are discussed. Finally, the challenges, solutions and prospects are highlighted to prompt the practical applications of Ru-based electrocatalysts for HER.

Study and Implement on Key Technologies of Ship-Welding Mobile Robot

2010 ◽  
Vol 44-47 ◽  
pp. 321-325
Author(s):  
Liang Hua ◽  
Lin Lin Lv ◽  
Ju Ping Gu ◽  
Yu Jian Qiang
Keyword(s):  
Mobile Robot ◽  
Control Method ◽  
Structure Design ◽  
Seam Tracking ◽  
Precision Positioning ◽  
Positioning Control ◽  
Controlling System ◽  
Welding Torch ◽  
Driven System ◽  
And Control

The key technilogies of ship-welding mobile robot applied to ship-building in plane block production line were researched and realized. The mechanical structure design of the robot was completed. The motion-controlling system of of two-wheel differential driving mobile robot was developed. A novel precision positioning control method of welding torch using ultrasonic motors was putforward. The mechanism and control-driven system of precision positioning system for welding torch were completed. The platform of obstacle avoidance navigation system was designed and the strategies of seam tracking, trajectory and posture adjustment were preliminary studied. The methods and results put forward in the paper could act as the base of deep research on the theories and technologies of ship-welding mobile robot.

Dynamic Analysis on a Cable-Driven Interventional Active Catheter Using Kane's Method Combined with Screw Theory

2014 ◽  
Vol 527 ◽  
pp. 140-145
Author(s):  
Da Xu Zhao ◽  
Bai Chen ◽  
Guo Zhong Shou ◽  
Yu Qi Gu
Keyword(s):  
Mathematical Model ◽  
Dynamic Analysis ◽  
Motion Control ◽  
Screw Theory ◽  
Driving Forces ◽  
Structure Design ◽  
Kinematics And Dynamics ◽  
Existing Problems ◽  
Blind Area ◽  
The Mathematical Model

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.

scholarly journals Simple Algebraic Expressions for the Prediction and Control of High-Temperature Annealed Structures by Linear Perturbation Analysis

2021 ◽  
Vol 26 (2) ◽  
pp. 43
Author(s):  
Constantino Grau Grau Turuelo ◽  
Cornelia Breitkopf
Keyword(s):  
High Temperature ◽  
Surface Diffusion ◽  
Perturbation Analysis ◽  
Algebraic Model ◽  
Structure Design ◽  
Linear Perturbation ◽  
Prediction And Control ◽  
Void Shape ◽  
Void Structure ◽  
And Control

The prediction and control of the transformation of void structures with high-temperature processing is a critical area in many engineering applications. In this work, focused on the void shape evolution of silicon, a novel algebraic model for the calculation of final equilibrium structures from initial void cylindrical trenches, driven by surface diffusion, is introduced. This algebraic model provides a simple and fast way to calculate expressions to predict the final geometrical characteristics, based on linear perturbation analysis. The obtained results are similar to most compared literature data, especially, to those in which a final transformation is reached. Additionally, the model can be applied in any materials affected by the surface diffusion. With such a model, the calculation of void structure design points is greatly simplified not only in the semiconductors field but in other engineering fields where surface diffusion phenomenon is studied.

Percolation phase transition of static and growing networks under a weighted function

2016 ◽  
Vol 27 (07) ◽  
pp. 1650082 ◽  
Author(s):  
Xiao Jia ◽  
Jin-Song Hong ◽  
Ya-Chun Gao ◽  
Hong-Chun Yang ◽  
Chun Yang ◽  
...  
Keyword(s):  
Phase Transition ◽  
Continuous Phase ◽  
Weighted Function ◽  
Percolation Process ◽  
Practical Applications ◽  
Network Intervention ◽  
Growing Networks ◽  
Discontinuous Phase ◽  
And Control ◽  
Growing Network

We investigate the percolation phase transitions in both the static and growing networks where the nodes are sampled according to a weighted function with a tunable parameter [Formula: see text]. For the static network, i.e. the number of nodes is constant during the percolation process, the percolation phase transition can evolve from continuous to discontinuous as the value of [Formula: see text] is tuned. Based on the properties of the weighted function, three typical values of [Formula: see text] are analyzed. The model becomes the classical Erdös–Rényi (ER) network model at [Formula: see text]. When [Formula: see text], it is shown that the percolation process generates a weakly discontinuous phase transition where the order parameter exhibits an extremely abrupt transition with a significant jump in large but finite system. For [Formula: see text], the cluster size distribution at the lower pseudo-transition point does not obey the power-law behavior, indicating a strongly discontinuous phase transition. In the case of growing network, in which the collection of nodes is increasing, a smoother continuous phase transition emerges at [Formula: see text], in contrast to the weakly discontinuous phase transition of the static network. At [Formula: see text], on the other hand, probability modulation effect shows that the nature of strongly discontinuous phase transition remains the same with the static network despite the node arrival even in the thermodynamic limit. These percolation properties of the growing networks could provide useful reference for network intervention and control in practical applications in consideration of the increasing size of most actual networks.

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