A Self-Deployment Hexapod Model for a Space Application

2008 ◽  
Vol 4 (1) ◽  
Author(s):  
G. Aridon ◽  
A. Al Majid ◽  
L. Blanchard ◽  
D. Rémond ◽  
R. Dufour
Keyword(s):  
Numerical Model ◽  
Dynamic Model ◽  
Strain Energy ◽  
The Self ◽  
Hysteretic Behavior ◽  
Simulation Tool ◽  
Space Application ◽  
Tensor Representation ◽  
Restoring Force ◽  
The Impact

This paper presents a simulation tool for predicting the self-deployment of an on-board deployable hexapod based on the release of strain energy stored in six tape-spring actuators. Their hysteretic behavior is described by six restoring force models, and a formulation of a direct dynamic model developed with a Lagrangian approach is performed. Furthermore, tensor representation is used to condense and simplify the calculation of Lagrangian partial derivatives. The results are compared with a numerical model that implements the recursive Newton–Euler technique. Finally, the impact of base excitations on the hexapod deployment performances is evaluated by using the proposed restoring force models.

A Self-Deployment Hexapod Model for a Space Application

2007 ◽  
Author(s):  
G. Aridon ◽  
A. Al Majid ◽  
L. Blanchard ◽  
D. Re´mond ◽  
R. Dufour
Keyword(s):  
Numerical Model ◽  
Dynamic Model ◽  
Hysteretic Behavior ◽  
Simulation Tool ◽  
Space Application ◽  
Tensor Representation ◽  
Restoring Force ◽  
Partial Derivatives ◽  
Efficient Simulation ◽  
The Impact

This paper presents an efficient simulation tool for predicting a self deployment of an on-board deployable hexapod based on the release of stored strain energies provided by six tape-spring actuators. Six restoring force models describe their hysteretic behavior. A formulation of a direct dynamic model developed with a Lagrangian approach is achieved. Furthermore, tensor representation is used to condense and simplify the calculation of Lagrangian partial derivatives. Results are compared with a numerical model that performs the recursive Newton-Euler technique. Finally, the impact of the excitation of the base on the deployment performances is evaluated taking advantage of the proposed restoring force models.

Effect of Frame-Restoring Force Characteristics on the Pounding Response of Multiple-Frame Bridges

2005 ◽  
Vol 21 (4) ◽  
pp. 1113-1135 ◽  
Author(s):  
Susendar Muthukumar ◽  
Reginald DesRoches
Keyword(s):  
Ground Motions ◽  
Near Field ◽  
Hysteretic Behavior ◽  
Impact Response ◽  
Far Field ◽  
Restoring Force ◽  
Bridge Model ◽  
Multiple Frame ◽  
The Impact ◽  
Force Characteristics

This study examines the effect of column hysteretic behavior on the impact response of adjacent frames in multiple-frame bridges. A simplified planar analytical bridge model is developed including inelastic frame action, nonlinear hinge behavior, and abutment effects. Pounding is simulated using a stereomechanical approach. The frame hysteretic models considered include the elasto-plastic and bilinear (traditional), Q-Hyst (stiffness-degrading), and pivot hysteresis (strength-degrading) models. Analytical studies conducted on adjacent bridge frames reveal that the traditional models underestimate the stiff frame displacement amplification due to pounding, and overestimate the flexible frame displacement amplification, when compared with other hysteretic models. A stiffness-degrading model is recommended to accurately estimate the pounding response of bridge frames subjected to far-field ground motion. The use of a strength-degrading model increases the stiff frame displacement amplification by 125% when compared to the stiffness-degrading model for highly out-of-phase frames, and is recommended in the presence of near-field ground motions.

The Dynamic Load of Inter-Shaft Bearing and its Transmission Characteristic of Complex Rotor System

2018 ◽  
Author(s):  
Huan Yu ◽  
Bo Sun ◽  
YanHong Ma ◽  
Jie Hong
Keyword(s):  
Dynamic Model ◽  
Dynamic Load ◽  
Strain Energy ◽  
Vibration Mode ◽  
Resonance State ◽  
Rotor System ◽  
Rotor Vibration ◽  
Restoring Force ◽  
Flexural Mode ◽  
Aero Engine

Aiming at the dynamic design of dual rotor of aero-engine, the dynamic model of dual rotor system was established. And then based on the simulation results of the dynamic model established above, the unbalance distribution of dual rotor and the strain energy distribution of the flexural deformation were analyzed. The results showed that the dynamic load on inter-shaft bearing is determined by the rotor vibration mode and the rotor vibration response at the position of bearing. The flexural deformation can also affect the dynamic load on inter-shaft bearing. Under the influence of elastic restoring force generated by the flexural deformation of rotors, the dynamic load on the inter-shaft bearing under flexural mode is higher than that under the rigid mode. It was found that large dynamic load may act on inter-shaft bearing even though the rotor is not operating in the resonance state. And due to the internal damping of the rotor, the large dynamic load on the inter-shaft bearing can be obviously reduced when the load transmit to other bearings via the rotor with flexural deformation.

Self-Compassion and Quality of Life in Adults Who Stutter

2020 ◽  
Vol 29 (4) ◽  
pp. 2097-2108
Author(s):  
Robyn L. Croft ◽  
Courtney T. Byrd
Keyword(s):  
Quality Of Life ◽  
Social Connectedness ◽  
The Self ◽  
Future Research ◽  
Self Compassion ◽  
Adults Who Stutter ◽  
And Gender ◽  
Relationship Of ◽  
The Impact

Purpose The purpose of this study was to identify levels of self-compassion in adults who do and do not stutter and to determine whether self-compassion predicts the impact of stuttering on quality of life in adults who stutter. Method Participants included 140 adults who do and do not stutter matched for age and gender. All participants completed the Self-Compassion Scale. Adults who stutter also completed the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed for self-compassion differences between and within adults who do and do not stutter and to predict self-compassion on quality of life in adults who stutter. Results Adults who do and do not stutter exhibited no significant differences in total self-compassion, regardless of participant gender. A simple linear regression of the total self-compassion score and total Overall Assessment of the Speaker's Experience of Stuttering score showed a significant, negative linear relationship of self-compassion predicting the impact of stuttering on quality of life. Conclusions Data suggest that higher levels of self-kindness, mindfulness, and social connectedness (i.e., self-compassion) are related to reduced negative reactions to stuttering, an increased participation in daily communication situations, and an improved overall quality of life. Future research should replicate current findings and identify moderators of the self-compassion–quality of life relationship.

332-OR: Determining the Impact of Additional Macronutrients on the Glycemic-Insulin Dynamic Model

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 332-OR
Author(s):  
BOYI JIANG ◽  
YUXIANG ZHONG ◽  
PRATIK AGRAWAL ◽  
TONI L. CORDERO ◽  
ROBERT VIGERSKY
Keyword(s):  
Dynamic Model ◽  
The Impact

Effect of Parental Modernity on Rejection Sensitivity and Self-Esteem of Adolescents

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Ritu ◽  
Madhu Anand
Keyword(s):  
Social Development ◽  
Rejection Sensitivity ◽  
Self Esteem ◽  
The Self ◽  
Negatively Associated ◽  
Individual Modernity ◽  
The Impact ◽  
The Relationship

Parental Modernity is an important aspect for the psycho-social development of the child. The present study aims to study the effect of parental modernity on rejection sensitivity and self-esteem of adolescents and the relationship between rejection sensitivity and self-esteem. The research is carried out on a sample of 240 parents (including 120 fathers and 120 mothers) and their 120 children. For observing the impact of modernity of parents on their children, Individual Modernity Scale was used and administered on father and mother. Rejection Sensitivity Questionnaire and Self-Esteem Inventory were used to measure the rejection sensitivity and self-esteem of children (age ranges from 14 to 19 years). The results suggest that parental modernity has an effect on the rejection sensitivity and personally perceived self of the self – esteem of adolescents. Furthermore, the rejection sensitivity has been found negatively associated with self-esteem.

Dynamic model for high-speed rotors based on their experimental characterization

2017 ◽  
Vol 2 (4) ◽  
pp. 25
Author(s):  
L. A. Montoya ◽  
E. E. Rodríguez ◽  
H. J. Zúñiga ◽  
I. Mejía
Keyword(s):  
Dynamic Model ◽  
High Speed ◽  
Natural Frequencies ◽  
Mode Shapes ◽  
Experimental Characterization ◽  
Rotating Systems ◽  
Computing Performance ◽  
The Impact ◽  
Stiffness Distribution ◽  
Good Agreement

Rotating systems components such as rotors, have dynamic characteristics that are of great importance to understand because they may cause failure of turbomachinery. Therefore, it is required to study a dynamic model to predict some vibration characteristics, in this case, the natural frequencies and mode shapes (both of free vibration) of a centrifugal compressor shaft. The peculiarity of the dynamic model proposed is that using frequency and displacements values obtained experimentally, it is possible to calculate the mass and stiffness distribution of the shaft, and then use these values to estimate the theoretical modal parameters. The natural frequencies and mode shapes of the shaft were obtained with experimental modal analysis by using the impact test. The results predicted by the model are in good agreement with the experimental test. The model is also flexible with other geometries and has a great time and computing performance, which can be evaluated with respect to other commercial software in the future.

Fluxus and the Absurd (1961–62)

2017 ◽  
Author(s):  
Benjamin R. Levy
Keyword(s):  
Second Life ◽  
The Self ◽  
Major Work ◽  
The Future ◽  
To Come ◽  
The Impact

After John Cage’s 1958 Darmstadt lectures, many European composers developed an interest in absurdity and artistic provocation. Although Ligeti’s fascination with Cage and his association with the Fluxus group was brief, the impact it had on his composition was palpable and lasting. A set of conceptual works, The Future of Music, Trois Bagatelles, and Poème symphonique for one hundred metronomes, fall clearly into the Fluxus model, even as the last has taken on a second life as a serious work. This spirit, however, can also be seen in the self-satire of Fragment and the drama and irony of Volumina, Aventures, and Nouvelles Aventures. The sketches for Aventures not only show the composer channeling this humor into a major work but also prove to be a fascinating repository of ideas that Ligeti would reuse in the years to come.

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