Design and Kinematic Analysis of a New Grapple Mechanism

2012 ◽  
Vol 605-607 ◽  
pp. 239-243
Author(s):  
Fei Deng ◽  
Jin Bao Chen ◽  
Meng Chen ◽  
Fu Jun Peng

Combined with China's demand for space station construction, a new type of lock system for end effector is developed. This grapple mechanism makes grappling, pulling and rigidization in one mechanism which is simple construction and high reliability. The composition and the working principle of this grapple mechanism are introduced. Then, the singularity of the mechanism is analyzed and its kinematics equations are established. The parameter variations are obtained by using PROE. The results show that the working process adapts to the variation of the motion and force between the end effector and target adapter perfectly.

Author(s):  
Mo Tao ◽  
Jun Wu ◽  
Zhiwu Ke ◽  
Xianling Li ◽  
Yong Li

Due to the increasingly complexity of the nuclear power device system, the demands for its performance and security become rather high. There is a large number of rotating machinery working in the nuclear power plant.The static and dynamic misalignment between the rotating mechanical rotors may exist for various reasons like installation error, loading deformation, thermal expansion deformation and etc.Both of the radial vibration and the axial vibration can be generated by the misalignment. The security of nuclear power is severely threatened by these vibrations. Compared with the mechanical gears, the merits of Field Modulated Magnetic Transmission System Based on Magnetic Conductivity Modulation Principle are remarkable.Since it has a high reliability, lower noise, smaller vibration and a capacity of protecting itself during overload. It also can reduce maintenances, moreover there is a physical isolation between input and output in the new system.Besides,the traditional magnetic transmission system has only a low torque transmitting density.But by the use of efficient permanent magnet, the new type magnetic field modulation gears’ high torque transmitting density is comparable to the mechanical ones, even better then them. The major work of this paper is extension. Researching of the Field Modulated Magnetic Transmission System (FMMTS) based on Magnetic Conductivity Modulation Principle. Considering about the particularity of the working principle and structure of the FMMTS.First the author studied and analyzed its working principle in details by using analytic method.Then deduced the mathematical relationship of the pole pairs of permanent magnet of inner rotor,the number of copper core in magnetic adjusting loop and the pole pairs of permanent magnet of outer rotor.After that, a mathematical model of torque and rotational speed over three factors: the inner rotor, the outer rotor and the magnetic adjusting loop, were modoled. On the basis of principle analysis, the author verified the medol and did some further analysis by finite element simulating.Then we obtained the torque transmission characteristics of the Field Modulated Magnetic Transmission System, including the characteristics of Static torque and steady torque. Based on the above researching, the author put forward the idea of the new type three-layer permanent magnet excitation High-power Field Modulated Magnetic Transmission System based on Halbach tech, that’s middle layer is also permanent magnet. By using the finite element method to analyze its magnetic flux distribution and torque characteristics.Compared with FMMTS under the same size, the new type system improved the power density dramatically.


2008 ◽  
Vol 07 (01) ◽  
pp. 65-67
Author(s):  
CHANGPING ZOU ◽  
LI DU ◽  
XIANDE HUANG

A new type of six-bar swaying machine was put forward, which is an ingenious combination of plane multi-bar mechanism and high pressure oil cylinder. Preliminary analysis shows that this machine has many advantages, such as the torque produced by its unit weight, its small size, its light deadweight, etc. Thus it can be applied to situations that need swaying mechanism with low rotational speed and great torque. Firstly, the mechanism composition and working principle of the swaying machine were introduced. Secondly, parameterized modeling of the mechanism was carried out by utilizing software ADAMS. Then kinematic analysis and kinetic analysis were completed by using ADAMS. Finally, key dimensions were adjusted according to kinetic analysis. These tasks are believed to be beneficial to the development of the novel transmission.


Author(s):  
DU Hui ◽  
GAO Feng ◽  
PAN Yang

A novel 3-UP3R parallel mechanism with six degree of freedoms is proposed in this paper. One most important advantage of this mechanism is that the three translational and three rotational motions are partially decoupled: the end-effector position is only determined by three inputs, while the rotational angles are relative to all six inputs. The design methodology via GF set theory is brought out, using which the limb type can be determined. The mobility of the end-effector is analyzed. After that, the kinematic and velocity models are formulated. Then, workspace is studied, and since the robot is partially decoupled, the reachable workspace is also the dexterous workspace. In the end, both local and global performances are discussed using conditioning indexes. The experiment of real prototype shows that this mechanism works well and may be applied in many fields.


2008 ◽  
Vol 07 (01) ◽  
pp. 51-54 ◽  
Author(s):  
HUI-XIA LIU ◽  
WEI WEI ◽  
XIAO WANG ◽  
LAN CAI

A knowledge-based intelligent die design system for automotive panels is developed by UG software platform. This system can accomplish design intelligently and automatically through engineering rules in the knowledge base. The framework and implementation of the system are discussed. Finally, a case study of the panel die design of car trunk in the system is implemented, which illustrates working process, working principle, implement method and practicability of the system, and validates the advanced design conception proposed in this paper.


10.5772/59350 ◽  
2014 ◽  
Vol 11 (12) ◽  
pp. 190 ◽  
Author(s):  
Youngjin Moon ◽  
Hyuk Jae Choi ◽  
Joon Beom Seo ◽  
Jaesoon Choi

2013 ◽  
Vol 281 ◽  
pp. 287-292 ◽  
Author(s):  
Ren Feng Zhao ◽  
Sheng Dun Zhao ◽  
Bin Zhong

This paper illuminates a new type of precision cropping process method with rotary striking action. The new process makes use of a controllable circumferential strike on a metal bar with a V-shaped notch. The working principle of the machine is described. Different types of metal bars have been tested, and both bad results and successful results were stated in the paper. The most ideal control mode has been obtained. The experimental results show that the new cropping process can crop bars with different materials and diameters. In some cases, it can be directly used in the subsequent industrial production.


2012 ◽  
Vol 602-604 ◽  
pp. 2273-2278
Author(s):  
Ping Zhang ◽  
Jia Chun Li

As a new process, the abrasive belt grinding plays an increasingly important role in the field of machining. It meets a variety of processing requirements. The concept of abrasive belt grinding and its working principle were introduced, and a new type of abrasive belt grinding equipment for removing the rust on steel wire surface was designed. Some key experiments for testing grinding force,the metal removal rate,belt wear rate、grinding ratio,grinding depth and wire speed were studied. The research work provides rational parameters for the pretreatment of rust removal in metal wire drawing processing.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1594
Author(s):  
Gabriela Fabiola Știufiuc ◽  
Valentin Toma ◽  
Anca Onaciu ◽  
Vasile Chiș ◽  
Constantin Mihai Lucaciu ◽  
...  

Chiral separation is an important issue for the pharmaceutical industry. Over the years, several separation methods have been developed, mainly based on chromatography. Their working principle is based on the formation of transient diastereoisomers, but the very subtle nanoscale interactions responsible for separation are not always understood. Recently, Raman and surface-enhanced Raman (SERS) spectroscopy have provided promising results in this field. Here we present Raman/SERS experimental data that provide useful information concerning the nanoscale interactions between propranolol enantiomers and α, β, and γ cyclodextrins. Raman spectroscopy was used to prove the formation of host–guest intermolecular complexes having different geometries of interaction. The occurrence of new vibrational bands and a change in the intensities of others are direct proofs of complexes’ formation. These observations were confirmed by DFT calculations. By performing SERS measurements on a new type of plasmonic substrate, we were able to prove the intermolecular interactions responsible for PRNL discrimination. It turned out that the interaction strength between the substrate and the intermolecular complexes is of paramount importance for SERS-based chiral discrimination. This approach could represent a very good starting point for the evaluation of molecular interactions manifesting between other pharmaceutical compounds and different classes of chiral selectors.


2021 ◽  
Author(s):  
Yifan Wu ◽  
Wen-Bin Shen

<p>VLBI technique plays important role in both astronomy and geodesy due its fantastic ability to determine the position of celestial bodies and the length of baseline on Earth. Moreover it also presents excellent work on time comparisons between atomic clocks located in remote positions where optical fiber links are not accessible. Due to its high reliability and stability, the information of Earth’s gravity field can be extracted from VLBI time comparisons in the framework of general relativity. In this study, we provide a formulation to determine the gravity potential difference by VLBI time comparisons. In fact the precision of the estimated gravity potential depends on the performance of participated clocks and the accuracy of time comparison technique. Thus we present simulation experiments using clocks with 10<sup>-16</sup>@1d stability and broadband VLBI observation and determine gravity potential difference within a VLBI network around world with 10 m<sup>2</sup>/s<sup>2 </sup>precision which is equivalent to 1 m in height. The results could be greatly improved using optical atomic clocks with much higher stabilities. Furthermore it can be applied to height transfer across oceans and unifying the height system. This study is supported by the National Natural Science Foundations of China (NSFC) under Grants 42030105, 41721003, 41804012, 41631072, 41874023, and Space Station Project (2020)228.</p>


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