Mobility Analysis of Symmetric Deployable Mechanisms Involved in a Coplanar 2-Twist Screw System

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Bing Li ◽  
Hailin Huang ◽  
Zongquan Deng
Keyword(s):  
Traditional Approach ◽  
Mobility Analysis ◽  
Kinematic Chains ◽  
Insight Into

In this paper, an intuitive approach for the mobility analysis of deployable mechanisms involved in a special screw system with two coplanar twist vectors is proposed. First, the coplanar screw system with a pair of parallel/concurrent zero pitch screws is analyzed, and the intuitive allowable mobility set for the screw system is described. Next, kinematic chains containing the coplanar screw system are enumerated. The proposed approach is used to explain the mobility of the deployable Bennett mechanism, Myard mechanism, and Bricard mechanism; some novel deployable mechanisms could be found based on the analysis. Furthermore, it is shown that the proposed approach can be applied to the mobility analysis of multiloop deployable mechanisms and is found to be more intuitive than the traditional approach, which provides a straightforward insight into the mobility of complicated mechanisms.

Mobility of Single Loop Linkages: A Final Word?

2007 ◽  
Author(s):  
Jose´ Mari´a Rico ◽  
J. Jesu´s Cervantes ◽  
Juan Rocha ◽  
Jaime Gallardo ◽  
Luis Daniel Aguilera ◽  
...  
Keyword(s):  
Mobility Analysis ◽  
Additional Insight ◽  
Final Word ◽  
Single Loop ◽  
Kinematic Chains ◽  
Recent Developments ◽  
The Subject ◽  
Insight Into

Setting aside paradoxical linkages such as Bennett’s, Bricard’s or Goldberg’s, the mobility of single loop linkages seemed, with the developments on mobility analysis carried out in the last five years, a closed chapter in kinematic research. However, recent developments on the mobility of parallel platforms have shed additional insight into the problem. This contribution attempts to unify the results obtained in the last five years in the area of mobility of single-loop kinematic chains to state what appears to be a final word on the subject.

Virtual Chain Approach for Mobility Analysis of Multiloop Deployable Mechanisms

2013 ◽  
Vol 135 (11) ◽  
Author(s):  
Hailin Huang ◽  
Zongquan Deng ◽  
Xiaozhi Qi ◽  
Bing Li
Keyword(s):  
Relative Motion ◽  
Twist Angle ◽  
Open Loop ◽  
Mobility Analysis ◽  
Link Length ◽  
Flexible Links ◽  
Single Loop ◽  
Kinematic Chains ◽  
In Series ◽  
Insight Into

In this paper, we present a virtual chain approach for the mobility analysis of multiloop deployable mechanisms. First, the relative motion of the links of single-loop units in multiloop mechanisms are analyzed using the equivalent motion of certain types of open-loop virtual kinematic chains; these kinematic chains comprise some types of joints connected in series by flexible links. This reveals that the links in these virtual chains are not rigid when the mechanism is moving. The parameters of these virtual kinematic chains (such as the link length, the twist angle of two adjacent revolute joint axes, and so on) are variable. By using this approach that involves equivalent kinematic chains, the multiloop mechanisms can be considered equivalent to single-loop mechanisms with flexible links; the closure equations of such multiloop mechanisms can also be derived. The analytical procedures are explained using examples of multiloop mechanisms in which Myard mechanisms as used as the basic single-loop units. A prototype is also fabricated to demonstrate the feasibility of the proposed multiloop mechanism. The proposed method yields a more intuitive and straightforward insight into the mobility of complicated multiloop mechanisms.

Protein Molecules as Natural Nano Bio Devices: Mobility Analysis

2010 ◽  
Author(s):  
Zahra Shahbazi ◽  
Horea T. Ilies¸ ◽  
Kazem Kazerounian
Keyword(s):  
Degrees Of Freedom ◽  
Conformational Transitions ◽  
Living Cells ◽  
Mobility Analysis ◽  
Folding Process ◽  
Kinematic Chains ◽  
Protein Molecules ◽  
Kinematic Models ◽  
Lower Mobility ◽  
Molecular Components

Proteins are nature’s nano-robots in the form of functional molecular components of living cells. The function of these natural nano-robots often requires conformational transitions between two or more native conformations that are made possible by the intrinsic mobility of the proteins. Understanding these transitions is essential to the understanding of how proteins function, as well as to the ability to design and manipulate protein-based nano-mechanical systems [1]. Modeling protein molecules as kinematic chains provides the foundation for developing powerful approaches to the design, manipulation and fabrication of peptide based molecules and devices. Nevertheless, these models possess a high number of degrees of freedom (DOF) with considerable computational implications. On the other hand, real protein molecules appear to exhibits a much lower mobility during the folding process than what is suggested by existing kinematic models. The key contributor to the lower mobility of real proteins is the formation of Hydrogen bonds during the folding process.

scholarly journals Intercultural Training: Learn to avoid treading on other people’s toes or experience walking in the other person’s shoes

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Kristin Rygg
Keyword(s):  
Intercultural Communication ◽  
Traditional Approach ◽  
The Other ◽  
Intercultural Training ◽  
Theoretical Discussion ◽  
Culture Clash ◽  
Interactive Tools ◽  
Case Work ◽  
Insight Into

This article raises the question of whether the traditional approach in intercultural training focusing on knowledge about cultural differences and skills to avoid culture clash is sufficient in order to prepare intercultural communication trainees for dynamic and psychologically demanding multicultural environments. Inspired by the concept of mentalizing in the psycho-therapeutic method called Mentalization-based treatment, training that encourages imaginatively “seeing the other from the inside and oneself from the outside” is suggested as better able to prepare for complex intercultural realities. Tolerance is seen as tolerance for being in the intercultural process as much as tolerance for others’ differences. A theoretical discussion between the notion of mentalizing in mentalization-based treatment and perceptions of empathy, imagination and mindfulness further provides insight into the role of interactive tools such as case work and role plays in intercultural training. These, in turn, are seen as best suited to fulfil the goals and ambitions of the theories. However, experiences gained from them must be verbalized in order to cause increased awareness.

Mobility Analysis of Thin-Panel Origamis Based on a Coplanar 2-Twist Screw System

2020 ◽  
Vol 142 (11) ◽  
Author(s):  
Sen Wang ◽  
Hailin Huang ◽  
Bing Li ◽  
Xiaojun Yang
Keyword(s):  
Traditional Approach ◽  
Analysis Approach ◽  
Mobility Analysis ◽  
The Third ◽  
Analysis Process ◽  
Thin Panel

Abstract This paper presents an intuitive approach for mobility analysis of thin-panel origamis based on a coplanar 2-twist screw system, which consists of a pair of parallel/concurrent line vectors. In this study, we first proved that in any thin-panel origami, the allowable instantaneous mobility for any two facets connected to a third one can be described by a coplanar 2-twist screw system because this mobility is generated by two coplanar creases in the third facet. Second, the mobility of the basic origami units with a single facet loop was analyzed by using this coplanar 2-twist screw system. Third, the mobility analysis approach was extended to analyze the mobility of other planar/circular arraying origami patterns with multiple facet loops; typical origami patterns such as leaf-fold, Miura-ori were subjected to this analysis process. Furthermore, we proved that the proposed approach can be applied to the mobility analysis of complicated origamis; this approach proved to be considerably more intuitive than the traditional approach for mobility analysis.

Modeling seed dispersal of black cherry, an invasive forest tree: how microsatellites may help?

2006 ◽  
Vol 36 (6) ◽  
pp. 1385-1394 ◽  
Author(s):  
Marie Pairon ◽  
Mathieu Jonard ◽  
Anne-Laure Jacquemart
Keyword(s):  
Traditional Approach ◽  
Forest Tree ◽  
Dispersal Distance ◽  
Prunus Serotina ◽  
Accurate Information ◽  
Black Cherry ◽  
Dispersal Curves ◽  
Seed Shadows ◽  
Dispersal Events ◽  
Insight Into

We used empirical models and three dispersal functions (Weibull, lognormal and 2Dt) to model seed distributions derived from the black cherry (Prunus serotina Ehrh.) understorey of a pine-dominated stand. Two different approaches were used to disentangle the overlapping seed shadows: the traditional inverse modeling approach and the genetic approach that uses microsatellite markers to assign a dispersed seed to its maternal parent. The distinction was made between the seeds passively dispersed by gravity (fruits with mesocarp) and those dispersed by birds (fruits without mesocarp). Our main objectives were to compare the three dispersal functions and assess the differences between the two approaches used. The functions performed equally well, but the lognormal function often showed a better data correlation. The best dispersal curves obtained by both traditional and genetic approaches were quite similar for the seeds dispersed by gravity, and 95% of these seeds were predicted to fall 5 and 3 m away from the parent tree for the traditional and genetic approaches, respectively. Differences were more important for the seeds dispersed by birds. The traditional approach predicted a lower number of seeds near the parent plant and a higher dispersal distance. Microsatellites provided accurate information on individual dispersal events and led to a better insight into the dispersal process.

Critical Review of Existing Degeneracy Testing and Mobility Type Identification Algorithms for Kinematic Chains

2005 ◽  
Author(s):  
Rajesh Pavan Sunkari ◽  
Linda C. Schmidt
Keyword(s):  
Critical Review ◽  
Kinematic Chain ◽  
Structural Studies ◽  
Mobility Analysis ◽  
Structural Synthesis ◽  
Common Error ◽  
Kinematic Chains ◽  
The Individual ◽  
Almost All ◽  
Mathematical Justification

Mobility analysis is one of the fundamental problems of structural studies of kinematic chains. Degeneracy testing, an important step in structural synthesis, can be considered as a part of the mobility analysis due to the similarity of the two problems. One common error in the algorithms for these two problems is the assumption that the graph of a planar kinematic chain is a planar graph. This work shows that almost all the mobility analysis algorithms, except that of Lee and Yoon, have this error. This work also critically reviews the two most efficient algorithms on degeneracy testing, those by Hwang and Hwang, and Lee and Yoon. It is shown that due to the errors in the Hwang and Hwang’s algorithm, it failed to identify some of the degenerate chains. Furthermore, the accuracy of the Lee and Yoon’s algorithms for mobility analysis and degeneracy testing is proved by providing the mathematical justification of the individual steps of the algorithms.

Rotatability Laws for N-Bar Kinematic Chains and Their Proof

1991 ◽  
Vol 113 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Kwun-Lon Ting ◽  
Yung-Way Liu
Keyword(s):  
Valuable Insight ◽  
Kinematic Chains ◽  
Special Case ◽  
Insight Into

This paper presents a thorough proof and adds valuable insight into the theorems [1] concerning the mobility of planar N-bar linkages. The paper includes four parts: the assemblability, the revolvability between two links, the full rotatability, and the classification. The proof is based on the assemblability condition of N-bar linkages and the revolvability condition of an angle. Examples are also provided to further clarify the use of these theorems. In these theorems, Grashof’s Law becomes a very special case.

scholarly journals Studying Unemployment Effects on Mental Health: Social Media versus Traditional Approach

2020 ◽  
Author(s):  
Samara Ahmed ◽  
Adil E. Rajput ◽  
Akil Sarirete ◽  
Asmaa Aljaberi ◽  
Ohoud Alghanem ◽  
...  
Keyword(s):  
Mental Health ◽  
Social Media ◽  
Traditional Approach ◽  
Human Life ◽  
Financial Strain ◽  
Involuntary Unemployment ◽  
Social Exchanges ◽  
Medical Practitioners ◽  
Health Social Media ◽  
Insight Into

Social media, traditionally reserved for social exchanges on the net, has been increasingly used by researchers to gain insight into different facets of human life. Unemployment is an area that has gained attention by researchers in various fields. Medical practitioners especially in the area of mental health have traditionally monitored the effects of involuntary unemployment with great interest. In this work, we compare the feedback gathered from social media using crowdsourcing techniques to results obtained prior to the advent of Big Data. We find that the results are consistent in terms of 1) financial strain is the biggest stressor and concern, 2) onslaught of depression is typical and 3) possible interventions including reemployment and support from friends and family is crucial in minimizing the effects of involuntary unemployment. Lastly, we could not find enough evidence to study effects on physical health and somatization in this work.

scholarly journals Die bydrae van ’n haalbare gasvryheids- en ontmoetingsetiek in die etiese versorging van gesondheidsorgwerkers

2015 ◽  
Vol 1 (1) ◽  
pp. 217
Author(s):  
Laetus Lategan ◽  
Roger Burggraeve ◽  
Linus Vanlaere
Keyword(s):  
South African ◽  
Healthcare Worker ◽  
Healthcare Workers ◽  
Traditional Approach ◽  
Real Life ◽  
New Paradigm ◽  
The Real ◽  
Ethical Care ◽  
Insight Into

<strong> The contribution of a doable hospitality and engagement ethics in the ethical care of healthcare workers</strong> <br /> The authors of this study advocate for the contribution a double ethic of hospitality and engagement can make towards the ethical care of healthcare workers. Their contribution is based on two studies in healthcare. The South African case outlines challenges with regard to resources, communication and expectations. The Belgium case study draws attention to the traditional approach and suggests a new paradigm, namely to respect the patient as subject and therefore the importance of meeting the patient in his/her situation. Both cases sensitise the reader to the ethical vulnerability of the healthcare worker suggesting that a double ethic of hospitality and engagement is needed to address this challenge. The question of ethical coaching is addressed via a real life example in which the healthcare workers are placed in a simulation laboratory and then treated as “patients” by other healthcare workers. This simulation gives insight into the real needs of patients and how healthcare workers should care for them.

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