Inverse Static Analysis of a Planar System With Spiral Springs

2000 ◽  
Author(s):  
Marco Carricato ◽  
Joseph Duffy ◽  
Vincenzo Parenti-Castelli
Keyword(s):  
Static Analysis ◽  
External Load ◽  
Degrees Of Freedom ◽  
The Other ◽  
Linear Functions ◽  
State Variables ◽  
Planar System ◽  
Equilibrium Configurations ◽  
Solving Equations ◽  
The One

Abstract In this article the inverse static analysis of a two degrees of freedom planar mechanism equipped with spiral springs is presented. Such analysis aims to detect the entire set of equilibrium configurations of the mechanism once the external load is assigned. While on the one hand the presence of flexural pivots represents a novelty, on the other it extremely complicates the problem, since it brings the two state variables in the solving equations to appear as arguments of both trigonometric and linear functions. The proposed procedure eliminates one variable and leads to write two equations in one unknown only. The union of the root sets of such equations constitutes the global set of solutions of the problem. Particular attention has been reserved to the analysis of the “reliability” of the final equations: it has been sought the existence of critical situations, in which the solving equations hide solutions or yield false ones. A numerical example is provided. Also, in Appendix it is shown a particular design of the mechanism that offers computational advantages.

Inverse Static Analysis of a Planar System With Flexural Pivots

2000 ◽  
Vol 123 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Marco Carricato ◽  
Vincenzo Parenti-Castelli ◽  
Joseph Duffy
Keyword(s):  
Static Analysis ◽  
External Load ◽  
Degrees Of Freedom ◽  
Linear Functions ◽  
State Variables ◽  
Special Design ◽  
Planar System ◽  
Planar Mechanism ◽  
Equilibrium Configurations ◽  
Solving Equations

This article presents the inverse static analysis of a two degrees of freedom planar mechanism with flexural pivots. Such analysis aims to detect the entire set of equilibrium configurations of the system once the external load is assigned. The presence of flexural pivots represents a novelty, although it remarkably complicates the problem since it causes the two state variables to appear in the solving equations as arguments of both trigonometric and linear functions. The proposed procedure eliminates one variable and leads to two equations in one unknown only. The union of the root sets of such equations constitutes the global set of solutions of the problem. Particular attention is paid to the analysis of the reliability of the final equations: critical situations, in which the solving equations may hide solutions or yield false ones, are studied. Finally, a numerical example is provided and, in the Appendix, a special design that offers computational advantages is proposed.

scholarly journals THE FORMATION OF PROFESSIONAL TALENT IN DETERMINATION WITH SEMANTIC ATTITUDE TO INNOVATIONS UNDER THE INFLUENCE OF VARIOUS DEGREES OF FREEDOM IN ACTIVITY

2020 ◽  
Vol 17 (4) ◽  
pp. 91-101
Author(s):  
T.N. Soboleva ◽  
Keyword(s):  
Empirical Data ◽  
Degrees Of Freedom ◽  
The Other ◽  
Psychological Analysis ◽  
Other Hand ◽  
Professional Talent ◽  
The One ◽  
The Impact ◽  
Three Degrees Of Freedom

The article is devoted to the poorly studied problem of the formation of talent in the conditions of different degrees of freedom in activity and the impact on that formation of a person’s conservative and innovative semantic attitudes towards the introduction of new equipment. The main objective of the study is to describe how the conditions of different degrees of freedom in the activity are refracted with internal conditions, which are conservative and innovative semantic attitudes and various talent structures. The study was conducted on a sample of 54 qualified railway drivers using a specialized simulator which allows to simulate three degrees of freedom in the activity. The psychological analysis of the activity revealed seven abilities ensuring the implementation of the activity. Based on empirical data, the article shows that low, medium and high degrees of freedom in activity are manifested in different degrees of productivity. Conservative and innovative semantic attitudes to the introduction of new equipment do not have a significant effect on the productivity of the activity in the conditions of different degrees of freedom. Along with this, depending on the conservative and innovative semantic attitudes, different structures of talent in terms of composition and degree of integration under the conditions of different degrees of freedom in the activity are formed. On the one hand, conservative and innovative semantic attitudes act as internal determinants; on the other hand, low, medium and high degrees of freedom in the activity act as external determinants of the formation of various talent structures.

Design of a Highly Integrated Active Magnetic Bearing With Six Coupled Actuators for High Precision Rotation Applications

1999 ◽  
Author(s):  
M. Kümmerle ◽  
B. Aeschlimann ◽  
J. Zoethout ◽  
T. Belfroid ◽  
R. Vuillemin ◽  
...  
Keyword(s):  
High Precision ◽  
Pid Controller ◽  
Degrees Of Freedom ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
The Other ◽  
Axial Forces ◽  
Functional Prototype ◽  
The One ◽  
Contact Free

Abstract This paper presents the design and the implementation of a contact free Active Magnetic Bearing (AMB) for high precision rotation applications. For controlling five Degrees of Freedom (DOF) of the rotor six coupled reluctance force actuators (creating radial and axial forces at the same time) are used. A method for designing the actuators in order to meet the specifications is described. Two different controller schemes using different sensor configurations have been implemented on a functional prototype: On the one hand a conventional decentralized PID controller, on the other hand a more centralized structure.

XIV.—Note on the Construction of an Orthogonant

1919 ◽  
Vol 38 ◽  
pp. 146-153
Author(s):  
Thomas Muir
Keyword(s):  
The Other ◽  
Linear Functions ◽  
The One ◽  
Image Position

(1) The essence of Cayley's mode* of arriving at the formation of an orthogonal substitution lies, as is known, in the observation that if two sets of variablesx, y, z, w, and ξ, η, ζ, ωbe taken linear functions of a third setin such a way that the determinant of the coefficients is in the one caseand in the other the conjugate of this, then the first and second set of variables are orthogonally related.

scholarly journals Comparación de la carga interna y externa en competición oficial de 3 vs. 3 y 5 vs. 5 en baloncesto femenino (Comparison of internal and external load in official 3 vs. 3 and 5 vs. 5 female basketball competitions)

Retos ◽  
2019 ◽  
pp. 400-405
Author(s):  
María Reina ◽  
Javier García Rubio ◽  
Antonio Antúnez ◽  
Sergio José Ibáñez
Keyword(s):  
External Load ◽  
Heat Rate ◽  
Study Groups ◽  
The Other ◽  
Specific Training ◽  
Internal Load ◽  
Other Hand ◽  
The One

La modalidad de juego de 3 vs. 3 en baloncesto es una nueva adaptación del baloncesto convencional (5 vs. 5) en auge. El objetivo de este trabajo consistió en describir los requerimientos de carga interna y externa que demandan ambas competiciones y, en segundo lugar, analizar las posibles diferencias existentes entre ellas. Dos grupos fueron analizados. Por un lado, 10 jugadoras pertenecientes a un equipo U21, el cuál disputó ocho partidos de liga regional en la modalidad cinco contra cinco (n=80). Por otro lado, ocho jugadoras pertenecientes a dos equipos U18 que disputaron tres partidos cada uno en el campeonato de España de la modalidad de tres contra tres (n=24). Se analizaron variables de carga interna: Frecuencia cardíaca media (HRAvg), máxima (HRMáx), % (%HRMáx) y zonas de intensidad (Z1, Z2, Z3, Z4, Z5, Z6); y variables de carga externa: Número de pasos, saltos e impactos por minuto a través del uso de inertial devices (IMUs). Las variables de HRAvg, %HRMáx, Z6, número de impactos y saltos por minuto fueron significativamente mayores en la modalidad de 3 vs. 3 (181,50 HRAvg frente a 171,16 ppm; 90,75 %HRMáx frente a 84,59 %; 85,16% en Z6 frente a 8,10%; 7,45 impactos por minuto frente a 1,65; y 4,50 saltos por minuto frente a 1,80). En el 5 vs. 5 se encontraron valores significativamente superiores en las zonas bajas e intermedias (Z1, Z2, Z3, Z4 y Z5) y en el número de pasos realizados por minuto (53,32 pasos por minuto frente a 44,40). Ambas modalidades tienen unas demandas diferentes en el juego y, por lo tanto, se deben prescribir entrenamientos específicos para cada modalidad, puesto que la competición también es diferente. Abstract. Three vs. three basketball is a new adaptation of conventional basketball (five vs. five) that is currently on the rise. The purpose of this study is to describe the internal and external load requirements demanded by both competitions and, in addition, to analyze the possible differences between them. Two study groups were analyzed. On the one hand, ten players belonging to a U21 team, who played eight regional league matches in the five vs. five modality (n = 80). On the other hand, eight players belonging to two U18 teams who played three matches each one in the three vs. three Spanish championship competition (n = 24). Internal load variables: Heat Rate mean (HRAvg), maximum (HRMáx), % (%HRMáx) and intensity zones; and external load variables: number of steps, jumps and impacts per minute were analyzed through the use of inertial devices (IMUs). The variables of HRAvg, % HRMáx, Z6, number of impacts and jumps were significantly higher in the 3 vs. 3 competition (181,50 HRAvg vs. 171,16 bpm; 90,75 %HRMáx vs. 84,59 %; 85,16% in Z6 vs. 8,10%; 7,45 impacts per minute vs. 1,65; y 4,50 jumps per minute vs. 1,80). In 5 vs. 5 significantly higher values were found in the low and intermediate zones (Z1, Z2, Z3, Z4 and Z5) and in the number of steps performed per minute (53,32 steps per minute vs. 44,40). Both modalities had different demands in the game and, therefore, specific training must be prescribed for each modality, since the competition is also different.

scholarly journals The Adaptive Behavior of a Soccer Team: An Entropy-Based Analysis

Entropy ◽  
2018 ◽  
Vol 20 (10) ◽  
pp. 758 ◽  
Author(s):  
Yair Neuman ◽  
Navot Israeli ◽  
Dan Vilenchik ◽  
Yochai Cohen
Keyword(s):  
Adaptive Behavior ◽  
Degrees Of Freedom ◽  
Tsallis Entropy ◽  
The Other ◽  
Premier League ◽  
Previous Season ◽  
Patterns Of Behavior ◽  
Soccer Team ◽  
The One ◽  
English Premier League

To optimize its performance, a competitive team, such as a soccer team, must maintain a delicate balance between organization and disorganization. On the one hand, the team should maintain organized patterns of behavior to maximize the cooperation between its members. On the other hand, the team’s behavior should be disordered enough to mislead its opponent and to maintain enough degrees of freedom. In this paper, we have analyzed this dynamic in the context of soccer games and examined whether it is correlated with the team’s performance. We measured the organization associated with the behavior of a soccer team through the Tsallis entropy of ball passes between the players. Analyzing data taken from the English Premier League (2015/2016), we show that the team’s position at the end of the season is correlated with the team’s entropy as measured with a super-additive entropy index. Moreover, the entropy score of a team significantly contributes to the prediction of the team’s position at the end of the season beyond the prediction gained by the team’s position at the end of the previous season.

SPLIT INVOLUTION AND SECOND CLASS CONSTRAINTS

1992 ◽  
Vol 07 (21) ◽  
pp. 1931-1943 ◽  
Author(s):  
I.A. BATALIN ◽  
S.L. LYAKHOVICH ◽  
I.V. TYUTIN
Keyword(s):  
Degrees Of Freedom ◽  
The Other ◽  
Phase Variable ◽  
Dirac Bracket ◽  
Quantization Scheme ◽  
Quantum Deformation ◽  
Conversion Method ◽  
Other Hand ◽  
The One

The new quantization scheme is proposed for theories with second class constraints. The formalism possesses the properties intermediate between those of the conversion method and quantum deformation of the Dirac bracket: on the one hand, all the phase variable operators have nonsingular commutators while the physical states are determined by weak equations; on the other hand, no extra degrees of freedom are introduced.

scholarly journals Wand-Like Interaction with a Hand-Held Tablet Device—A study on Selection and Pose Manipulation Techniques

Information ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 152
Author(s):  
Ali Samini ◽  
Karljohan Lundin Palmerius
Keyword(s):  
Degrees Of Freedom ◽  
The Other ◽  
Smart Devices ◽  
Gaze Control ◽  
Interaction Techniques ◽  
3D Interaction ◽  
The Common ◽  
Tablet Device ◽  
The One ◽  
6 Degrees Of Freedom

Current hand-held smart devices are supplied with powerful processors, high resolution screens, and sharp cameras that make them suitable for Augmented Reality (AR) applications. Such applications commonly use interaction techniques adapted for touch, such as touch selection and multi-touch pose manipulation, mapping 2D gestures to 3D action. To enable direct 3D interaction for hand-held AR, an alternative is to use the changes of the device pose for 6 degrees-of-freedom interaction. In this article we explore selection and pose manipulation techniques that aim to minimize the amount of touch. For this, we explore and study the characteristics of both non-touch selection and non-touch pose manipulation techniques. We present two studies that, on the one hand, compare selection techniques with the common touch selection and, on the other, investigate the effect of user gaze control on the non-touch pose manipulation techniques.

Vertex-Splitting on a Diamond Origami Pattern

2019 ◽  
Vol 11 (3) ◽  
Author(s):  
Xiao Zhang ◽  
Yan Chen
Keyword(s):  
Degrees Of Freedom ◽  
The Other ◽  
Splitting Schemes ◽  
Engineering Applications ◽  
Splitting Technique ◽  
Kinematic Property ◽  
Vertex Splitting ◽  
The One ◽  
Three Degrees Of Freedom

A diamond origami pattern is a well-known origami pattern consisting of identical six-crease vertices. As each vertex can be modeled as a spherical 6R linkage with three degrees of freedom (DOF), the tessellated pattern with multiple vertices is a multi-DOF system, which makes it difficult to fully control the motion in the desired symmetric manner. Here, two splitting schemes on the diamond vertex are proposed to generate three types of unit patterns to reduce the DOF. This vertex-splitting technique is applied to the multivertex diamond origami pattern to produce several one-DOF basic assemblies, which form a number of one-DOF origami patterns. Two of the one-DOF origami patterns are discussed: one of which is a flat-foldable origami pattern mixed with four- and six-crease vertices and the other is a nonflat-foldable one mixed with four-, five-, and six-crease vertices. In the one-DOF patterns, the symmetrically kinematic property of the original diamond origami pattern is well kept. Such property would significantly facilitate engineering applications comparing to the multi-DOF origami patterns. It also paves a new road to construct one-DOF origami patterns.

Roll Motion of a Ship and the Roll Stabilising Effect of Bilge Keels

2008 ◽  
Vol 61 (4) ◽  
pp. 667-686 ◽  
Author(s):  
Santiago Iglesias Baniela
Keyword(s):  
Natural Frequency ◽  
Degrees Of Freedom ◽  
The Other ◽  
Roll Motion ◽  
Natural Period ◽  
Six Degrees Of Freedom ◽  
Damping Effect ◽  
Mass Damper ◽  
Points Of View ◽  
The One

The roll motion of a ship on waves is one of the six degrees of freedom and is the most difficult to predict since it deals with a motion similar to a spring-mass damper system, poorly damped by ship generated waves, in addition to the action of waves from the high seas. This problem increased from the second half of the 19th century when sailing propulsion was replaced by steam machines and iron replaced wood, which led to design modifications in ships affecting transversal stability, with the result of an increment in the ship's roll motion. As a consequence, it has been necessary to develop different systems which, on the one hand, increase the natural period of this motion in order to decrease its amplitude and reduce the risks that the wave encounter frequency would resonate with the natural frequency of the ship's motion; and on the other hand, to generate a damping effect to this motion. Bilge keels, passive stabilisers with no moving parts, form the simplest and cheapest element that may be incorporated on a ship to reduce this motion. This paper studies roll motion in general and then analyses bilge keels from different points of view.

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