Parametric Design of Parallel Force/Velocity Actuators: Force Balance Analysis

2008 ◽  
Author(s):  
Dinesh Rabindran ◽  
Delbert Tesar
Keyword(s):  
Power Analysis ◽  
Parametric Design ◽  
Companion Paper ◽  
Force Balance ◽  
Specific Design ◽  
Analytical Work ◽  
Balance Analysis ◽  
Force Velocity ◽  
Commercial Off The Shelf ◽  
Work Done

This paper adds to the analytical work done in a companion paper [3]. In that work, the power analysis for a Parallel Force/Velocity Actuator was carried out. In this work, we present a force balance analysis of the same actuator. In so doing, we consider a link driven by a Parallel Force/Velocity Actuator and study the balance of static and inertial forces in this system. The results from this study include design maps for the PFVA including the effects listed above. We also present five specific design examples of the PFVA using commercial off-the-shelf components to illustrate our force balance analysis.

Parametric Design of Parallel Force/Velocity Actuators: Force Distribution Analysis

2010 ◽  
Vol 2 (1) ◽  
Author(s):  
Dinesh Rabindran ◽  
Delbert Tesar
Keyword(s):  
Parametric Design ◽  
Design Guidelines ◽  
Effective Stiffness ◽  
Design Parameters ◽  
Force Distribution ◽  
Relative Distribution ◽  
Distribution Analysis ◽  
Dimensionless Parameters ◽  
Force Velocity ◽  
Commercial Off The Shelf

In this paper we present the force distribution analysis for a dual input actuator called parallel force/velocity actuator (PFVA). We present five physical quantities that are relevant to the design and operation of PFVA-based systems. For each of them we (i) follow a first principles approach to develop a model, (ii) define dimensionless parameters and criteria that indicate the relative distribution of the quantity between the two inputs of the PFVA, (iii) express the basic model in terms of these dimensionless parameters, (iv) provide numerical examples using five candidate designs with commercial off-the-shelf components, (v) investigate the limiting case as the two inputs become more and more kinematically distinct, and (vi) suggest design guidelines based on our analysis. We studied four aspects of PFVA design: (i) mixing of position uncertainties of the two inputs, i.e., force actuator (FA) and velocity actuator (VA), (ii) distribution of static and inertia torques between the inputs for a given output loading condition, (iii) acceleration responsiveness, and lastly, (iv) effective stiffness of the PFVA system with respect to some basic design parameters of the PFVA. As an example result, we observed that the PFVA's effective stiffness will be at least 40% greater than that of the VA if the FA is 85% as efficient as the VA, the FA is 17% less stiff than the VA, and the kinematic scaling between the two inputs (FA and VA) is approximately 11.5. The results we obtained are organized into five design guidelines for the PFVA. To demonstrate the utility of this analysis and the guidelines, we present a design case study that describes a PFVA prototype. The results of this paper assist in better designing PFVA-based systems with a focus on the coupling between the two inputs.

Development of Lift-Off Diameter Model of Bubbles Generated on Horizontal Tube

2014 ◽  
Author(s):  
Sung Uk Ryu ◽  
Seok Kim ◽  
Dong-Jin Euh
Keyword(s):  
Heated Surface ◽  
Horizontal Tube ◽  
Force Balance ◽  
Convective Boiling ◽  
Azimuthal Position ◽  
Flux Partitioning ◽  
Balance Analysis ◽  
Lift Off ◽  
The Moment ◽  
Surrounding Liquid

In this study, the theoretical correlation for the lift-off diameter of bubbles generated on a horizontal tube is proposed. A force balance analysis in the direction normal to the heated surface at the moment of the bubble lift-off was performed to develop the model. According to the developed model, the bubble lift-off diameter depends strongly on the azimuthal position of the horizontal tube, the relative velocity between a bubble and surrounding liquid, the properties of the bubble, and the liquid. The developed model can be applicable to define the sub-model of wall heat flux partitioning for natural and forced convective boiling.

scholarly journals Theoretical and Experimental Estimation of the Stored Energy of Plain Knitted Fabrics Using Yarn Pullout Test

2012 ◽  
Vol 7 (1) ◽  
pp. 155892501200700 ◽  
Author(s):  
Azita Asayesh ◽  
Elaheh Niazkhani ◽  
Ali Asghar Asgharian Jeddi
Keyword(s):  
Pullout Test ◽  
Polyester Fabric ◽  
Force Balance ◽  
Stored Energy ◽  
Knitted Fabrics ◽  
Pull Out ◽  
Plain Knitted Fabric ◽  
Stitch Length ◽  
Balance Analysis ◽  
Reasonable Prediction

The yarn pullout test is a suitable method for investigating the internal mechanical properties of the fabric structure which is established during the weaving or knitting process. In this study, a theoretical model is presented to estimate the stored energy of plain-knitted fabrics which is determined using yarn pullout. The model can predict the stored energy in the fabric, based on the fabric dimensional properties of stitch length and yarn contact angle using force balance analysis. Moreover, in order to evaluate the suggested model, three types of plain-knitted fabric from cotton, cotton/polyester and cotton/nylon with three different stitch lengths were produced and subjected to pull-out tests. Comparison between experimental and theoretical results, demonstrates a reasonable prediction. The results show that the cotton/polyester fabric has the maximum stored energy, because of its higher yarn to yarn friction coefficient. It was also found that, the increase in fabric's loop length leads to a decrease in the fabric's stored energy.

scholarly journals Analitiese konsepte in middel-Foucault

2012 ◽  
Vol 68 (1) ◽  
Author(s):  
Johann Beukes
Keyword(s):  
Michel Foucault ◽  
Power Analysis ◽  
Middle Part ◽  
Diagnostic Tools ◽  
Middle Phase ◽  
Central Concept ◽  
Social Inquiry ◽  
Work Done

Analytic concepts in middle Foucault. This article investigates prominent analytic concepts in the philosophical historiographies of Michel Foucault (1926–1984), with specific regards to the work done in the middle phase of his career. These concepts accentuate the relation between history, power and contingency within the context of social inquiry. The author qualifies a particular order in the isolation of these concepts from the middle part of Foucault’s oeuvre: the notion of present history is introduced as the central concept in Foucault’s analyses from this period. It is argued that the notion of present history sustains Foucault’s other unique historiographical and socio-diagnostic tools from the particular period, namely archaeology, genealogy, discourse and power analysis. The article contributes to Foucaultian scholarship by periodising these concepts within the larger oeuvre, without subordinating Foucault to the parameters of his own ‘method’.

Generic grammars for design domains

2018 ◽  
Vol 32 (2) ◽  
pp. 225-239 ◽  
Author(s):  
José Beirão ◽  
José P. Duarte
Keyword(s):  
Urban Design ◽  
Parametric Design ◽  
Information Modeling ◽  
Frank Lloyd Wright ◽  
Andrea Palladio ◽  
Specific Design ◽  
Design Languages ◽  
Definition Of ◽  
Design Style ◽  
Alvaro Siza

AbstractShape grammars have been developed to codify a specific type of artifact – Queen Anne houses, Buffalo bungalows – or the style of a particular designer – Andrea Palladio, Frank Lloyd Wright, or Álvaro Siza Vieira. However, these specific grammars fail to encode recurrent design moves or features that are above the particularities of a specific design style or the idiosyncrasies of a specific designer and, therefore, are common to a larger category of designs and maybe reutilized and incorporated in the definition of new, specific design languages. To overcome these limitations, the notion of generic grammars for defining design domains is introduced. Its application to the urban design domain is illustrated by showing a generic grammar implementation resulting in a City Information Modeling platform composed of a parametric design interface connected to a geographic database.

Vehicle dynamics modelling for the National Advanced Driving Simulator

2002 ◽  
Vol 216 (4) ◽  
pp. 307-318 ◽  
Author(s):  
G J Heydinger ◽  
M K Salaani ◽  
W R Garrott ◽  
P A Grygier
Keyword(s):  
Traffic Safety ◽  
Vehicle Dynamics ◽  
Driving Simulator ◽  
Field Tests ◽  
Companion Paper ◽  
Dynamics Simulation ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Dynamics Modelling ◽  
Work Done

This paper provides an overview of the development of a vehicle dynamics simulation model for use on the National Highway Traffic Safety Administration's (NHTSA's) National Advanced Driving Simulator. The paper describes fundamental aspects of models used to represent rigid body chassis and suspension systems, powertrain, tyres, brakes, steering and aerodynamics. Representative data from laboratory measurements, instrumented field tests and simulation runs of a 1997 Jeep Cherokee Sport are presented to illustrate simulation development and validation efforts. A companion paper to this one also uses Jeep Cherokee data. Both papers highlight current capabilities and methodologies employed by two organizations that have worked, often collaboratively, to advance the state of the art of vehicle dynamics modelling and simulation validation. This paper features work done by NHTSA's Vehicle Research and Test Center; the companion paper reports on work done by Systems Technology, Incorporated (STI).

scholarly journals REVIEW OF ANALYTICAL WORK DONE ABROAD IN 1905.

1906 ◽  
Vol 28 (12) ◽  
pp. 1736-1776
Author(s):  
Benton Dales
Keyword(s):  
Analytical Work ◽  
Work Done

Parametric Study and Improvement of Phase Separation in Intermediate Headers of Microchannel Condensers

2018 ◽  
Author(s):  
Jun Li ◽  
Pega Hrnjak
Keyword(s):  
Phase Separation ◽  
Parametric Study ◽  
Separation Efficiency ◽  
Mechanistic Model ◽  
Force Balance ◽  
Visual Access ◽  
Fluid Properties ◽  
Balance Analysis ◽  
R 134A ◽  
Air Conditioning Systems

Phase separation has been proven to be beneficial to air-cooled parallel flow microchannel condensers for air conditioning systems. The inlet to the condenser with phase separation is located at the middle of the condenser height. After the first pass, in the vertical second header of the condenser, vapor phase separates from liquid phase mainly due to gravitational effects. In ideal case vapor should go to the top exit and liquid to the bottom exit, resulting in increased heat transfer. Due to interaction between vapor and liquid, separation is not perfect, expressed through the separation efficiency. This paper presents a parametric study of phase separation efficiency in the intermediate headers, with the target to improve separation efficiency. Header prototypes which have two exits are made with transparent PVC to simulate the real header and provide visual access. Using R-134a as a baseline, the measurement of separation efficiency and its general trend will be shown first. The results are compared to those of a mechanistic model based on flow regime and force balance analysis. Inlet mass flux in simulation is controlled at 87 kg·m−2·s−1 – 311 kg·m−2·s−1 and inlet quality at 0.05–0.25. The observed flow patterns in header are compared with the modeling results as well. Then, the header diameter is increased, which effectively improves the separation efficiency due to reduction of vapor velocity in header. Finally, R245fa and R32 are modeled in comparison with R-134a to discuss the effect of fluid properties on separation efficiency.

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