Design Optimization of a Prismatic-Revolute-Revolute Joint Hand for Grasping From Unconstrained Vehicles

2017 ◽  
Author(s):  
Spencer B. Backus ◽  
Aaron M. Dollar
Keyword(s):  
Parametric Model ◽  
The Body ◽  
Design Parameters ◽  
Small Space ◽  
Revolute Joint ◽  
Wide Range ◽  
Grasping And Manipulation ◽  
Interaction Task ◽  
The Impact ◽  
Or Task

Adding grasping and manipulation capabilities to unconstrained vehicles such as UAVs, AUVs, and small space craft so that they can deliver cargo, grasp and retrieve objects, perch on features in the environment, and even manipulating their environment is an ongoing area of research. However, these efforts have relied heavily on structuring the interaction task and have predominantly utilized existing gripper designs that were not specialized for the platform or task. In this paper, we present a parametric model of a novel underactuated hand design that is composed of prismatic-revolute-revolute joint fingers. This kinematic configuration attempts to minimize disturbance forces to the body of the vehicle while achieving stable grasps on a wide range of objects under significant positional uncertainty. In particular, this paper investigates the impact of various design parameters, including the relative link lengths and force allocation across the three joints, on grasping performance and suggests optimal design parameters for a prototype hand.

Making Up 3D Bodies

2021 ◽  
Vol 4 (2) ◽  
pp. 1-9
Author(s):  
Kiona Hagen Niehaus ◽  
Rebecca Fiebrink
Keyword(s):  
Software Tool ◽  
The Body ◽  
Design Parameters ◽  
Artistic Practice ◽  
Human Form ◽  
Modeling Systems ◽  
Exploratory Approach ◽  
Disability Status ◽  
High Level ◽  
The Impact

This paper describes the process of developing a software tool for digital artistic exploration of 3D human figures. Previously available software for modeling mesh-based 3D human figures restricts user output based on normative assumptions about the form that a body might take, particularly in terms of gender, race, and disability status, which are reinforced by ubiquitous use of range-limited sliders mapped to singular high-level design parameters. CreatorCustom, the software prototype created during this research, is designed to foreground an exploratory approach to modeling 3D human bodies, treating the digital body as a sculptural landscape rather than a presupposed form for rote technical representation. Building on prior research into serendipity in Human-Computer Interaction and 3D modeling systems for users at various levels of proficiency, among other areas, this research comprises two qualitative studies and investigation of the impact on the first author's artistic practice. Study 1 uses interviews and practice sessions to explore the practices of six queer artists working with the body and the language, materials, and actions they use in their practice; these then informed the design of the software tool. Study 2 investigates the usability, creativity support, and bodily implications of the software when used by thirteen artists in a workshop. These studies reveal the importance of exploration and unexpectedness in artistic practice, and a desire for experimental digital approaches to the human form.

scholarly journals Hyaluronan and the Fascial Frontier

2021 ◽  
Vol 22 (13) ◽  
pp. 6845
Author(s):  
Rebecca L. Pratt
Keyword(s):  
Nerve Fibers ◽  
The Body ◽  
Water Volume ◽  
Cell Behavior ◽  
Connective Tissues ◽  
Wide Range ◽  
The World ◽  
Extracellular Microenvironment ◽  
The Impact ◽  
The Relationship

The buzz about hyaluronan (HA) is real. Whether found in face cream to increase water volume loss and viscoelasticity or injected into the knee to restore the properties of synovial fluid, the impact of HA can be recognized in many disciplines from dermatology to orthopedics. HA is the most abundant polysaccharide of the extracellular matrix of connective tissues. HA can impact cell behavior in specific ways by binding cellular HA receptors, which can influence signals that facilitate cell survival, proliferation, adhesion, as well as migration. Characteristics of HA, such as its abundance in a variety of tissues and its responsiveness to chemical, mechanical and hormonal modifications, has made HA an attractive molecule for a wide range of applications. Despite being discovered over 80 years ago, its properties within the world of fascia have only recently received attention. Our fascial system penetrates and envelopes all organs, muscles, bones and nerve fibers, providing the body with a functional structure and an environment that enables all bodily systems to operate in an integrated manner. Recognized interactions between cells and their HA-rich extracellular microenvironment support the importance of studying the relationship between HA and the body’s fascial system. From fasciacytes to chronic pain, this review aims to highlight the connections between HA and fascial health.

scholarly journals Flow-induced vibrations of a rotating cylinder in an arbitrary direction

2018 ◽  
Vol 860 ◽  
pp. 739-766 ◽  
Author(s):  
Rémi Bourguet
Keyword(s):  
Three Dimensional ◽  
Rotating Cylinder ◽  
The Body ◽  
Arbitrary Direction ◽  
Fast Rotation ◽  
Flow Past ◽  
Symmetrical Configuration ◽  
Wide Range ◽  
Flow Induced Vibrations ◽  
The Impact

The flow-induced vibrations of an elastically mounted circular cylinder, free to oscillate in an arbitrary direction and forced to rotate about its axis, are examined via two- and three-dimensional simulations, at a Reynolds number equal to 100, based on the body diameter and inflow velocity. The behaviour of the flow–structure system is investigated over the entire range of vibration directions, defined by the angle $\unicode[STIX]{x1D703}$ between the direction of the current and the direction of motion, a wide range of values of the reduced velocity $U^{\star }$ (inverse of the oscillator natural frequency) and three values of the rotation rate (ratio between the cylinder surface and inflow velocities), $\unicode[STIX]{x1D6FC}\in \{0,1,3\}$, in order to cover the reference non-rotating cylinder case, as well as typical slow and fast rotation cases. The oscillations of the non-rotating cylinder ($\unicode[STIX]{x1D6FC}=0$) develop under wake-body synchronization or lock-in, and their amplitude exhibits a bell-shaped evolution, typical of vortex-induced vibrations (VIV), as a function of $U^{\star }$. When $\unicode[STIX]{x1D703}$ is increased from $0^{\circ }$ to $90^{\circ }$ (or decreased from $180^{\circ }$ to $90^{\circ }$), the bell-shaped curve tends to monotonically increase in width and magnitude. For all angles, the flow past the non-rotating body is two-dimensional with formation of two counter-rotating spanwise vortices per cycle. The behaviour of the system remains globally the same for $\unicode[STIX]{x1D6FC}=1$. The principal effects of the slow rotation are a slight amplification of the VIV-like responses and widening of the vibration windows, as well as a limited asymmetry of the responses and forces about the symmetrical configuration $\unicode[STIX]{x1D703}=90^{\circ }$. The impact of the fast rotation ($\unicode[STIX]{x1D6FC}=3$) is more pronounced: VIV-like responses persist over a range of $\unicode[STIX]{x1D703}$ but, outside this range, the system is found to undergo a transition towards galloping-like oscillations characterised by amplitudes growing unboundedly with $U^{\star }$. A quasi-steady modelling of fluid forcing predicts the emergence of galloping-like responses as $\unicode[STIX]{x1D703}$ is varied, which suggests that they could be mainly driven by the mean flow. It, however, appears that flow unsteadiness and body motion remain synchronised in this vibration regime where a variety of multi-vortex wake patterns are uncovered. The interaction with flow dynamics results in deviations from the quasi-steady prediction. The successive steps in the evolution of the vibration amplitude versus $U^{\star }$, linked to wake pattern switch, are not captured by the quasi-steady approach. The flow past the rapidly-rotating, vibrating cylinder becomes three-dimensional over an interval of $\unicode[STIX]{x1D703}$ including the in-line oscillation configuration, with only a minor effect on the system behaviour.

scholarly journals The true cost of in-patient obesity: impact of obesity on inflammatory stress and morbidity

2010 ◽  
Vol 69 (4) ◽  
pp. 511-517 ◽  
Author(s):  
Robert F. Grimble
Keyword(s):  
Inflammatory Cytokines ◽  
Inflammatory Cytokine ◽  
Cytokine Production ◽  
The Body ◽  
Morbidity And Mortality ◽  
Metabolic Effects ◽  
Inflammatory Cytokine Production ◽  
Inflammatory Stress ◽  
Wide Range ◽  
The Impact

The objective of the present review is to provide an overview of the metabolic effects of pro-inflammatory cytokine production during infection and injury; to highlight the disadvantages of pro-inflammatory cytokine production and inflammatory stress on morbidity and mortality of patients; to identify the influence of genetics and adiposity on inflammatory stress in patients and to indicate how nutrients may modulate the inflammatory response in patients. Recent research has shown clearly that adipose tissue actively secretes a wide range of pro- and anti-inflammatory cytokines. Paradoxically, although inflammation is an essential part of the response of the body to infection, surgery and trauma, it can adversely affect patient outcome. The metabolic effects of inflammation are mediated by pro-inflammatory cytokines. Metabolic effects include insulin insensitivity, hyperlipidaemia, muscle protein loss and oxidant stress. These effects, as well as being present during infective disease, are also present in diseases with a covert inflammatory basis. These latter diseases include obesity and type 2 diabetes mellitus. Inflammatory stress also increases during aging. The level of cytokine production, within individuals, is influenced by single nucleotide polymorphisms (SNP) in cytokine genes. The combination of SNP controls the relative level of inflammatory stress in both overt and covert inflammatory diseases. The impact of cytokine genotype on the intensity of inflammatory stress derived from an obese state is unknown. While studies remain to be done in the latter context, evidence shows that these genomic characteristics influence morbidity and mortality in infectious disease and diseases with an underlying inflammatory basis and thereby influence the cost of in-patient obesity. Antioxidants andn-3 PUFA alter the intensity of the inflammatory process. Recent studies show that genotypic factors influence the effectiveness of immunonutrients. A better understanding of this aspect of nutrient–gene interactions and of the genomic factors that influence the intensity of inflammation during disease will help in the more effective targeting of nutritional therapy.

Experimental study of passive vibration suppression using absorber with spherical ball impact damper

2016 ◽  
Vol 231 (17) ◽  
pp. 3193-3201 ◽  
Author(s):  
Riadh Chaari ◽  
Fathi Djemal ◽  
Fakher Chaari ◽  
Mohamed Slim Abbes ◽  
Mohamed Haddar
Keyword(s):  
Vibration Suppression ◽  
Industrial Applications ◽  
Design Parameters ◽  
Particle Impact ◽  
Ball Impact ◽  
Impact Damper ◽  
Ball Size ◽  
Wide Range ◽  
The Impact ◽  
Impact Damping

Impact dampers are efficient in many industrial applications with a wide range of frequencies. An experimental analysis of the impact damping of spherical balls is investigated to simplify the particle impact damping design and improve the vibration suppression. The objective of the study is to analyze some of the design parameters of impact damper using spherical balls. The experimental investigation consists to test the effect of the ball size for each mass level, the number of balls for each size level and different exciting force levels on vibrations of the main structure. The parametric study provided useful information to understand and optimize Particle Impact Damping design.

scholarly journals On the Impact of Climate Change on Building Energy Consumptions: A Meta-Analysis

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 354
Author(s):  
Ludovica Maria Campagna ◽  
Francesco Fiorito
Keyword(s):  
Climate Change ◽  
Energy Consumption ◽  
Climate Change Impacts ◽  
Building Energy ◽  
The Body ◽  
Building Energy Consumption ◽  
Adaptation Measures ◽  
Climate Zones ◽  
Wide Range ◽  
The Impact

The body of literature on climate change impacts on building energy consumption is rising, driven by the urgency to implement adaptation measures. Nevertheless, the multitude of prediction methodologies, future scenarios, as well as climate zones investigated, results in a wide range of expected changes. For these reasons, the present review aims to map climate change impacts on building energy consumption from a quantitative perspective and to identify potential relationships between energy variation and a series of variables that could affect them, including heating and cooling degree-days (HDDs and CDDs), reference period, future time slices and IPCC emission scenarios, by means of statistical techniques. In addition, an overview of the main characteristics of the studies related to locations investigated, building types and methodological approaches are given. To sum up, global warming leads to: (i) decrease in heating consumptions; (ii) increase in cooling consumption; (iii) growth in total consumptions, with notable differences between climate zones. No strong correlation between the parameters was found, although a moderate linear correlation was identified between heating variation and HDDs, and total variation and HDDs. The great variability of the collected data demonstrates the importance of increasing specific impact studies, required to identify appropriate adaptation strategies.

Investigation of the Influence of Consequential Design Parameters on the Mechanical Performance of Biodegradable Bone Scaffolds, Fabricated Using Pneumatic Micro-Extrusion Additive Manufacturing Process

2020 ◽  
Author(s):  
Daguan Zhao ◽  
Mohan Yu ◽  
Logan Lawrence ◽  
Pier Paolo Claudio ◽  
James B. Day ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Additive Manufacturing ◽  
High Resolution ◽  
Functional Properties ◽  
Manufacturing Process ◽  
Design Parameters ◽  
Bone Scaffolds ◽  
Material Deposition ◽  
Wide Range ◽  
The Impact

Abstract Pneumatic micro-extrusion (PME) is a high-resolution direct-write additive manufacturing process, which has emerged as the process of choice for tissue engineering and biofabrication of a broad spectrum of organs and tissues (e.g., bone, aortic valve, blood vessels, human ear, and nose). Despite the advantages and host of biomedical applications engendered by the PME process — including, for example, (i) accommodation of a wide range of material viscosity (enabled via thermopneumatic material deposition), (ii) large build volume and standoff distance for tissue engineering, (iii) in situ UV curing, and (iv) high-resolution multimaterial deposition — there are intrinsically complex design, material, and process factors as well as interactions, which influence the functional properties of PME-fabricated tissues and organs. Consequently, investigation of the impact and interaction of each factor aligned with establishment of a physics-based, optimal material deposition regime is inevitably a burgeoning need. In this study, using the Taguchi design, the influence of four significant factors, i.e., layer height, infill density, infill pattern, and print speed, is investigated on the compression properties as well as the dimensional accuracy of polycaprolactone (PCL) bone scaffolds, fabricated using the PME process. Furthermore, a 3D, transient two-phase flow CFD model is forwarded with the aim to observe the flow of material within the deposition head as well as the micro-capillary (nozzle). The results of this study pave the way for further investigation of the bio-functional properties of bone scaffolds, e.g., biodegradation, cell proliferation and growth rate.

Model construction of engagement and outcomes in consumers food life

2019 ◽  
Vol 121 (1) ◽  
pp. 218-239 ◽  
Author(s):  
Saman Sheikhesmaeili ◽  
Sana Hazbavi
Keyword(s):  
Customer Satisfaction ◽  
The Body ◽  
Food Marketing ◽  
Sufficient Evidence ◽  
Equation Modeling ◽  
Valuable Insight ◽  
Content Type ◽  
Wide Range ◽  
The Impact ◽  
Customer Satisfaction And Loyalty

Purpose The purpose of this paper is to determine the impact of food-related lifestyle (FRL) and food-related personality traits (FRPTs) on customer satisfaction and loyalty so that sufficient evidence for forming a new pattern of predictors of customer satisfaction and loyalty can be explored. Design/methodology/approach The research method in this study was the descriptive type and was based on the goal of the applied research methods. Data were collected from 384 sample group consumers of chain stores in the city of Tehran. The hypothesized relationships were tested using structural equation modeling (SEM). Findings Final results of study showed the significant effects of FRL and FRPT on satisfaction and loyalty of consumers. This indicates that aforementioned variables can create customer satisfaction and loyalty toward food. The research conceptual model was confirmed with goodness of fit. Research limitations/implications First, the sample consisted of customers who use a wide range of food despite diverse motives and interests. While knowing that costumers’ specific traits about food would have provided a more detailed and comprehensive understanding, conducting research in a set of general food consumer without considering special foods category could be a limitation. Second, and more importantly, since the customer behavior in consumption choices is an unconscious and cognitive process, other factors and domain that are linked to customer satisfaction and loyalty would have been missed. Practical implications This study shows that understanding the behavioral aspects of food consumption can help food producing companies to adjust their production and specially to foresee changes. Marketers are advised to investigate customer traits to promote customer satisfaction and loyalty effectively. This paper contributes to the body of knowledge in food marketing. Originality/value The present study offers a unique and valuable insight into a customer’s behavior and deepens customer satisfaction and loyalty by incorporating FRL, food neophobia scale and food involvement scale as independent variables to contribute knowledge in the context of food marketing, and throws some light upon the predictive power of mentioned variables on customer behaviors.

A computer model of human thermoregulation for a wide range of environmental conditions: the passive system

1999 ◽  
Vol 87 (5) ◽  
pp. 1957-1972 ◽  
Author(s):  
Dusan Fiala ◽  
Kevin J. Lomas ◽  
Martin Stohrer
Keyword(s):  
Numerical Procedure ◽  
Analytic Solutions ◽  
The Body ◽  
Activity Level ◽  
Passive System ◽  
Active System ◽  
Directional Radiation ◽  
Wide Range ◽  
Surface Convection ◽  
The Impact

A dynamic model predicting human thermal responses in cold, cool, neutral, warm, and hot environments is presented in a two-part study. This, the first paper, is concerned with aspects of the passive system: 1) modeling the human body, 2) modeling heat-transport mechanisms within the body and at its periphery, and 3) the numerical procedure. A paper in preparation will describe the active system and compare the model predictions with experimental data and the predictions by other models. Here, emphasis is given to a detailed modeling of the heat exchange with the environment: local variations of surface convection, directional radiation exchange, evaporation and moisture collection at the skin, and the nonuniformity of clothing ensembles. Other thermal effects are also modeled: the impact of activity level on work efficacy and the change of the effective radiant body area with posture. A stable and accurate hybrid numerical scheme was used to solve the set of differential equations. Predictions of the passive system model are compared with available analytic solutions for cylinders and spheres and show good agreement and stable numerical behavior even for large time steps.

An Experimental Investigation of Wave Impact Loads on a Slender Horizontal Cylinder

2014 ◽  
Author(s):  
Joseph F. Haley ◽  
Chris Swan ◽  
Richard Gibson
Keyword(s):  
Water Surface ◽  
Impact Load ◽  
Horizontal Cylinder ◽  
The Body ◽  
Impact Loads ◽  
Wave Impact ◽  
Wide Range ◽  
Wave Event ◽  
Vector Sum ◽  
The Impact

This paper concerns the difficulties arising in the prediction of the impact loads associated with an extreme wave event. A new set of experimental observations are presented. These concern the impact loads arising on a slender horizontal cylinder located at varying elevations above the still water level. The experimental observations incorporate a wide range of wave forms. In each case, data is provided describing (i) the incident water surface profiles, (ii) the incident fluid velocities and (iii) the load components acting on the cylinder. Comparisons between the measured data and the classical impact load solutions confirm a number of important departures. In particular, it is shown that as the wave becomes very steep (approaching the breaking limit) the vector sum of the horizontal and vertical velocity components at the water surface may deviate significantly from the normal to the local water surface. In such cases it becomes unclear exactly what direction the impact force acts. The present data suggests that this is, in part, dependent on the rate of inundation of the body. Furthermore, the present results also show that if the direction of the force is correct modelled, the variations in the predicted loading (or slamming) coefficient are much reduced.

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