scholarly journals Motion Behavior and Range of Motion when Using Exoskeletons in Manual Assembly Tasks

2020 ◽  
Author(s):  
Estela Perez Luque ◽  
Dan Högberg ◽  
Aitor Iriondo Pascual ◽  
Dan Lämkull ◽  
Francisco Garcia Rivera
Keyword(s):  
Range Of Motion ◽  
Musculoskeletal Disorders ◽  
Motion Capture ◽  
Point Of View ◽  
Manual Assembly ◽  
Manual Task ◽  
Work Tasks ◽  
Manual Tasks ◽  
Set Up ◽  
Assembly Tasks

Although the automation level is high within the automotive industry, there are still a large number of manual tasks, especially is the final assembly of the vehicle. Overhead assembly operations is an example of a problematic manual task that can cause workers to develop musculoskeletal disorders in the shoulder complex. Exoskeletons may be a solution to reduce the risk for developing musculoskeletal disorders from the work tasks. This study evaluates and compares how the use of three different passive upper body exoskeletons affects the range of motion (ROM) of workers at overhead assembly tasks. An experiment consisting of three tasks was set up in order to analyze the differences between the models. Seventeen subjects were involved in the study. Interviews, observations, videos and motion capture recordings were the methods of collecting data. The results show agreement from all the subjects that the exoskeletons help the worker at this specific assembly operation. The results also show that different exoskeleton models cause different levels of ROM reductions. The subjects’ opinions about how the different exoskeletons influence the ROM corresponds with the analysis of the motion capture data. Positive and negative aspects of each exoskeleton from a ROM and an implementation point of view are discussed. In general, the results indicate that the exoskeleton models can be applicable for the type of work tasks studied. However, the exoskeletons would benefit from further development in order to decrease ROM limitations and therefore cover a larger number of different manual assembly tasks.

Integration of Immersive Environment and RULA for Real-Time Study of Workplace Related Musculoskeletal Disorders in the Upper Limb

2003 ◽  
Author(s):  
Imtiyaz Shaikh ◽  
YoungJun Kim ◽  
Sankar Jayaram ◽  
Uma Jayaram ◽  
Hongsoo Choi
Keyword(s):  
Pilot Study ◽  
Real Time ◽  
Musculoskeletal Disorders ◽  
Upper Limb ◽  
Virtual Assembly ◽  
Human Model ◽  
Industrial Workers ◽  
Limb Injuries ◽  
Manual Tasks ◽  
Set Up

The assessment of musculoskeletal disorders prevalent among industrial workers involved in manual tasks is a difficult and time-consuming process. This paper presents the integration of the rapid upper limb assessment (RULA) algorithm, a well-established ergonomic tool, with a virtual assembly tool (VADE), to facilitate the identification of potential upper limb injuries in assembly processes and identification of potential solutions. In this context, a parametric human model was embedded into the virtual assembly system. The posture of the worker is analyzed continuously (at each frame) in real-time, as he/she performs the task. This allows the engineer to try out different postures and assembly processes quickly to identify the best work environment set-up. One pilot study is presented in this paper to demonstrate the application of this concept. This pilot study (conducted jointly with an industry partner) clearly illustrates the validity and utility of this method in identifying and reducing manual assembly process related musculoskeletal stresses.

The Revolutionizing of the Revolution

2017 ◽  
Author(s):  
R. R. Palmer
Keyword(s):  
French Revolution ◽  
Point Of View ◽  
Strict Sense ◽  
French Government ◽  
Thing In Itself ◽  
Set Up ◽  
The Moment ◽  
The French Revolution ◽  
The Revolution

In 1792, the French Revolution became a thing in itself, an uncontrollable force that might eventually spend itself but which no one could direct or guide. The governments set up in Paris in the following years all faced the problem of holding together against forces more revolutionary than themselves. This chapter distinguishes two such forces for analytical purposes. There was a popular upheaval, an upsurge from below, sans-culottisme, which occurred only in France. Second, there was the “international” revolutionary agitation, which was not international in any strict sense, but only concurrent within the boundaries of various states as then organized. From the French point of view these were the “foreign” revolutionaries or sympathizers. The most radical of the “foreign” revolutionaries were seldom more than advanced political democrats. Repeatedly, however, from 1792 to 1799, these two forces tended to converge into one force in opposition to the French government of the moment.

scholarly journals On Kaufmann's theory of the impact of the pianoforte hammer

1920 ◽  
Vol 97 (682) ◽  
pp. 99-110 ◽  
Keyword(s):  
Initial Conditions ◽  
Practical Importance ◽  
Prima Facie ◽  
Point Of View ◽  
Infinite Length ◽  
Modes Of Vibration ◽  
Rigorous Treatment ◽  
The Subject ◽  
Set Up ◽  
The Impact

The theory of the vibrations of the pianoforte string put forward by Kaufmann in a well-known paper has figured prominently in recent discussions on the acoustics of this instrument. It proceeds on lines radically different from those adopted by Helmholtz in his classical treatment of the subject. While recognising that the elasticity of the pianoforte hammer is not a negligible factor, Kaufmann set out to simplify the mathematical analysis by ignoring its effect altogether, and treating the hammer as a particle possessing only inertia without spring. The motion of the string following the impact of the hammer is found from the initial conditions and from the functional solutions of the equation of wave-propagation on the string. On this basis he gave a rigorous treatment of two cases: (1) a particle impinging on a stretched string of infinite length, and (2) a particle impinging on the centre of a finite string, neither of which cases is of much interest from an acoustical point of view. The case of practical importance treated by him is that in which a particle impinges on the string near one end. For this case, he gave only an approximate theory from which the duration of contact, the motion of the point struck, and the form of the vibration-curves for various points of the string could be found. There can be no doubt of the importance of Kaufmann’s work, and it naturally becomes necessary to extend and revise his theory in various directions. In several respects, the theory awaits fuller development, especially as regards the harmonic analysis of the modes of vibration set up by impact, and the detailed discussion of the influence of the elasticity of the hammer and of varying velocities of impact. Apart from these points, the question arises whether the approximate method used by Kaufmann is sufficiently accurate for practical purposes, and whether it may be regarded as applicable when, as in the pianoforte, the point struck is distant one-eighth or one-ninth of the length of the string from one end. Kaufmann’s treatment is practically based on the assumption that the part of the string between the end and the point struck remains straight as long as the hammer and string remain in contact. Primâ facie , it is clear that this assumption would introduce error when the part of the string under reference is an appreciable fraction of the whole. For the effect of the impact would obviously be to excite the vibrations of this portion of the string, which continue so long as the hammer is in contact, and would also influence the mode of vibration of the string as a whole when the hammer loses contact. A mathematical theory which is not subject to this error, and which is applicable for any position of the striking point, thus seems called for.

Error Estimation for Known Marker Position Retrieval by Ideal Pinhole Camera Direct Observation

2016 ◽  
Vol 841 ◽  
pp. 192-197
Author(s):  
Constantin Radu Mirescu ◽  
Gabriela Roșca
Keyword(s):  
Gait Analysis ◽  
Error Estimation ◽  
Motion Capture ◽  
Direct Observation ◽  
Focal Point ◽  
Pinhole Camera ◽  
Point Of View ◽  
Direct Approach ◽  
Marker Position

For Motion Capture in Gait Analysis using Known Spherical Markers one simple direct approach is to compute the projection of the Marker Center using its projection in the Pixel Plane and based on it to find the location of the Marker on the line that connects the Marker Center Projection and the camera Focal Point. For various positions of the Marker in the workspace the exact image of the marker is computed using a genuine approach and compute back the approximation of the position based on the generated image. Various algorithms are taken in consideration and finally the results are assessed from the point of view of Gait Analysis and two directions for calculus improvement are identified.

Atomistic Aspects of Fracture Modelling in the Framework of Continuum Mechanics

1998 ◽  
Vol 538 ◽  
Author(s):  
F. Cleri
Keyword(s):  
Continuum Mechanics ◽  
Constitutive Relations ◽  
Point Of View ◽  
Atomic Scale ◽  
Continuum Models ◽  
Cohesive Law ◽  
Macroscopic Models ◽  
Scale Models ◽  
Level Information ◽  
Set Up

AbstractThe validity and predictive capability of continuum models of fracture rests on basic informations whose origin lies at the atomic scale. Examples of such crucial informations are, e.g., the explicit form of the cohesive law in the Barenblatt model and the shear-displacement relation in the Rice-Peierls-Nabarro model. Modem approaches to incorporate atomic-level information into fracture modelling require to increase the size of atomic-scale models up to millions of atoms and more; or to connect directly atomistic and macroscopic, e.g. finite-elements, models; or to pass information from atomistic to continuum models in the form of constitutive relations. A main drawback of the atomistic methods is the complexity of the simulation results, which can be rather difficult to rationalize in the framework of classical, continuum fracture mechanics. We critically discuss the main issues in the atomistic simulation of fracture problems (and dislocations, to some extent); our objective is to indicate how to set up atomistic simulations which represent well-posed problems also from the point of view of continuum mechanics, so as to ease the connection between atomistic information and macroscopic models of fracture.

Translator and translation research: general descriptions of concepts

2019 ◽  
Author(s):  
Darian Jancowicz-Pitel
Keyword(s):  
Quantitative Method ◽  
Point Of View ◽  
Translation Process ◽  
Translation Research ◽  
Qualitative And Quantitative ◽  
The Third ◽  
Part Time ◽  
Set Up ◽  
Translation Errors ◽  
Multiple Languages

The presented paper aimed for exploring the translation process, a translator or interpreter needs equipment or tools so that the objectives of a translation can be achieved. If an interpreter needs a pencil, paper, headphones, and a mic, then an interpreter needs even more tools. The tools required include conventional and modern tools. Meanwhile, the approach needed in research on translation is qualitative and quantitative, depending on the research objectives. If you want to find a correlation between a translator's translation experience with the quality or type of translation errors, a quantitative method is needed. Also, this method is very appropriate to be used in research in the scope of teaching translation, for example from the student's point of view, their level of intelligence regarding the quality or translation errors. While the next method is used if the research contains translation errors, procedures, etc., it is more appropriate to use qualitative methods. Seeing this fact, these part-time translators can switch to the third type of translator, namely free translators. This is because there is an awareness that they can live by translation. These translators set up their translation efforts that involve multiple languages.

From observation to enactment: Can dance experience enhance multisensory temporal integration?

2012 ◽  
Vol 25 (0) ◽  
pp. 188
Author(s):  
Helena Sgouramani ◽  
Chris Muller ◽  
Leon van Noorden ◽  
Marc Leman ◽  
Argiro Vatakis
Keyword(s):  
Motion Capture ◽  
Temporal Integration ◽  
Stimulus Onset ◽  
Point Of View ◽  
Motion Capture System ◽  
Temporal Window ◽  
Synchronous Condition ◽  
First Time ◽  
Method Of Constant Stimuli

We report two experiments aiming to define how experience and stimulus enactment affect multisensory temporal integration for ecologically-valid stimuli. In both experiments, a number of different dance steps were used as audiovisual displays at a range of stimulus onset asynchronies using the method of constant stimuli. Participants were either professional dancers or non-dancers. In Experiment 1, using a simultaneity judgment (SJ) task, we aimed at defining — for the first time — the temporal window of integration (TWI) for dancers and non-dancers and the role of experience in SJ performance. Preliminary results showed that dancers had smaller TWI in comparison to non-dancers for all stimuli tested, with higher complexity (participant rated) dance steps requiring larger auditory leads for both participant groups. In Experiment 2, we adapted a more embodied point of view by examining how enactment of the stimulus modulates the TWIs. Participants were presented with simple audiovisual dance steps that could be synchronous or asynchronous and were asked to synchronize with the audiovisual display by actually performing the step indicated. A motion capture system recorded their performance at a millisecond level of accuracy. Based on the optimal integration hypothesis, we are currently looking at the data in terms of which modality will be dominant, considering that dance is a spatially (visual) and temporally (audio) coordinated action. Any corrective adjustments, accelerations–decelerations, hesitations will be interpreted as indicators of the perception of ambiguity in comparison to their performance at the synchronous condition, thus, for the first time, an implicit SJ response will be measured.

On the Notion of Collective Intelligence

2010 ◽  
Vol 1 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Epaminondas Kapetanios
Keyword(s):  
Collective Intelligence ◽  
Point Of View ◽  
Social Web ◽  
Synergistic Interactions ◽  
Design And Implementation ◽  
Computing Paradigm ◽  
The Social ◽  
Challenging Research ◽  
Research Questions ◽  
Set Up

In this article, the author explores the notion of Collective Intelligence (CI) as an emerging computing paradigm. The article is meant to provide a historical and contextual view of CI through the lenses of as many related disciplines as possible (biology, sociology, natural and environmental sciences, physics) in conjunction with the computer science point of view. During this explorative journey, the article also aims at pinpointing the current strengths and weaknesses of CI-related computational and system engineering design and implementation methodologies of CI-based systems. A non-exhaustive list of case studies set up the stage for CI applications as well as challenging research questions. These can be particularly directed towards the Social Web, as a very prominent example of synergistic interactions of a group of people with diverse cultural and professional backgrounds and its potential to become a platform for the emergence of truly CI-based systems.

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