scholarly journals A Twisted String, Flexure Hinges Approach for Design of a Wearable Haptic Thimble

Actuators ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 211
Author(s):  
Daniele Leonardis ◽  
Luca Tiseni ◽  
Domenico Chiaradia ◽  
Antonio Frisoli
Keyword(s):  
Fem Analysis ◽  
Design Guidelines ◽  
Flexure Hinge ◽  
Output Force ◽  
Twisted String ◽  
Present Design ◽  
Measuring Frequency ◽  
Pulling Force ◽  
The Cost ◽  
Sense Of Touch

Wearable haptic devices in the shape of actuated thimbles are used to render the sense of touch in teleoperation and virtual reality scenarios. The design of similar devices has to comply with concurring requirements and constraints: lightweight and compactness, intensity and bandwidth of the rendered signals. Micro-sized motors require a mechanical reduction to increase the output force, at the cost of noise and vibrations introduced by conventional gear reducers. Here we propose a different actuation method, based on a miniaturized twisted string actuator and a flexure hinge transmission mechanism. The latter is required to transmit and transform the pulling force of the twist actuator to a pushing force of the plate in contact with the fingerpad. It achieves a lightweight and noiseless actuation in a compact mechanism. In this work, we present design guidelines of the proposed approach, optimization, and FEM analysis of the flexure hinge mechanism, implementation of the prototype, and experimental characterization of the twist actuator measuring frequency response and output force capabilities.

Design and Direct Assembly of 2.5D/3D Rigid Silicon Interposer on PCB

2014 ◽  
Vol 2014 (1) ◽  
pp. 000783-000786 ◽  
Author(s):  
Farhang Yazdani
Keyword(s):  
Flip Chip ◽  
Thermal Stresses ◽  
Stress Test ◽  
Temperature Cycle ◽  
3D Integration ◽  
Test Vehicle ◽  
Direct Assembly ◽  
Solder Balls ◽  
Present Design ◽  
The Cost

Silicon interposer is emerging as a vehicle for integrating dies with sub 50um bump pitch in 2.5D/3D configuration. Benefits of 2.5D/3D integration are well explained in the literature, however, cost and reliability is a major concern especially with the increase in interposer size. Among the challenges, reliability issues such as warpage, cracks and thermal-stresses must be managed, in addition, multi-layer build-up flip chip substrate cost and its impact on the overall yield must be considered. Because of these challenges, 2.5D/3D silicon interposer has developed a reputation as a costly process. To overcome the reliability challenges and cost associated with typical thin interposer manufacturing and assembly, a rigid silicon interposer type structure is disclosed. In this study, interposer with thickness of greater than 300um is referred to as rigid interposer. Rigid silicon interposer is directly assembled on PCB without the need for intermediary substrate. This eliminates the need for an intermediary substrate, thin wafer handling, wafer bonding/debonding procedures and Through Silicon Via (TSV) reveal processes, thus, substantially reducing the cost of 2.5D/3D integrated products while improving reliability. A 10X10mm2 rigid silicon interposer test vehicle with 310um thickness was designed and fabricated. BGA side of the interposer with 1mm ball pitch was bumped with eutectic solder balls through a reflow process. Interposer was then assembled on a 50X50mm2 FR-4 PCB. We present design and direct assembly of the rigid silicon interposer on PCB followed by temperature cycle results using CSAM images at 250, 500, 750 and 1000 cycles. It is shown that all samples successfully passed the temperature cycle stress test.

Design and FEM Analysis of a Large Turning Table

2014 ◽  
Vol 494-495 ◽  
pp. 606-610
Author(s):  
Wei Shun Wang ◽  
Qing Zhang ◽  
Hong Liang Ma ◽  
Cheng Dong Hong ◽  
Jin Liang Wang ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Carrying Capacity ◽  
Fem Analysis ◽  
Good Effect ◽  
Modal Shape ◽  
Element Analysis ◽  
Double Ring ◽  
The Finite Element Analysis ◽  
Three Body ◽  
The Cost

Introducing the design of a large turning table. The table structure is combined with three-body, double-ring hydrostatic guide-way consists of inner and outer rings, it has the advanced features of high carrying capacity, high rigidity, high precision and good holding of the second fitting precision. Table rigidity and former six-stage modal shape are resulted by the finite element analysis, the result proves the rationality of the design. The design has been applied to the 25m vertical lathe successfully and obtained a good effect. The design solved lots of questions such as casting and machining and transport of a large table, it has reduced the cost greatly.

Stress Analysis for Shrink Fitting System Used for Ceramics Conveying Rollers

2008 ◽  
Vol 385-387 ◽  
pp. 513-516 ◽  
Author(s):  
Hendra ◽  
Masakazu Tsuyunaru ◽  
Naoaki Noda ◽  
Yasushi Takase
Keyword(s):  
Fracture Toughness ◽  
Stress Analysis ◽  
Maximum Stress ◽  
Fem Analysis ◽  
Maximum Tensile Stress ◽  
Iron And Steel ◽  
Rolling Mills ◽  
Shrink Fitting ◽  
New Type ◽  
The Cost

Cast iron and steel conveying rollers used in hot rolling mills must be changed very frequently because conveyed strips with high temperature induces wear on the roller surface in short periods. This failure automatically stops the production line for repair and maintenance of conveying rollers. In this study a new type of roller is considered where a ceramics sleeve is connected with two short shafts at both ends by shrink fitting. Here, a ceramics sleeve provides longer life and therefore reduces the cost for the maintenance. However, for the hollow ceramics rollers, care should be taken for maximum tensile stresses appearing at both edges of the sleeve. In particular, because fracture toughness is extremely smaller compared with the value of steel, stress analysis for the roller is necessary for ceramics sleeve. In this study FEM analysis is applied to the structure, and the maximum stress has been investigated with varying the dimensions of the structure. It is found that the maximum tensile stress appearing at the end of sleeves takes a minimum value at a certain amount of shrink fitting ratio.

scholarly journals Use Effects on the Reflection of Macro Textured Surfaces

2016 ◽  
Vol 6 (1) ◽  
pp. 51-56
Author(s):  
P. A Ixtaina ◽  
A. Armas ◽  
B. Bannert ◽  
G.H. Marin
Keyword(s):  
Initial Conditions ◽  
Design Guidelines ◽  
Textured Surfaces ◽  
Temperature Spectrum ◽  
Street Lighting ◽  
The Road ◽  
Present Design ◽  
Lighting Systems ◽  
On The Road ◽  
The Impact

Abstract The emergence of led luminaries in street lighting has modified traditional design guidelines. The highest led energy efficiency allows keeping suitable lighting levels with less installed power. Thus, the present design line of a street lighting installation is closely related to the technological change: kind of led to be used, suitable lens, efficacy relationship regarding high pressure sodium, light colour temperature, spectrum. The “impact” associated to with led conversion relegates main aspects of street designs: effect of road reflective properties and installation depreciation. The wear produced by traffic, as well as the environmental conditions gradually modifies the road reflection matrix. In a street lighting installation, this change alters the luminance arrangement on the road together with the perception conditions. This phenomenon is a determining factor within the global concept of depreciation affecting lighting systems in general and also street lighting installations designed by the Luminance Technique. In the present work changes, due to use, in the shape of street reflection matrices of Argentinean highways are analyzed. The analyzed r-tables were obtained through “in-situ” measurements, with road reflectometer. A first group corresponds to the initial conditions of macro textured roads which were measured in the period 2001/2003. The second studied set contains r-tables of the same type, and according to its use the surfaces can be considered in steady state, assessed between 2005 and 2009. The study provides information about the shape of matrixes and its alteration, specularity and scale factor, relating such parameters with the possible effects on the resulting lighting.

Turbocirculator for High Temperature Gas-Cooled Reactors

1970 ◽  
Author(s):  
J. Yampolsky ◽  
G. Melese D’Hospital ◽  
L. Cavallaro ◽  
V. J. Barbat
Keyword(s):  
High Temperature ◽  
Prestressed Concrete ◽  
Thermodynamic Cycle ◽  
Supply System ◽  
The Other ◽  
Pumping Power ◽  
Present Design ◽  
The Cost ◽  
Reactor Pressure ◽  
High Temperature Gas

The present design study was part of a program undertaken for the purpose of determining the feasibility, establishing the development requirements, and estimating the cost of a turbocirculator to provide the pumping power for a 1000-MWe High Temperature Gas Cooled Reactor (HTGR). Methods were developed for the optimization of the thermodynamic cycle and the design point of the turbocirculator components. A comparison of a turbocirculator to other ways of pumping helium in a HTGR is also shown in this paper. A design of the machine with its associated bearing and seal system and gas conduits was carried out. An important feature of this design is incorporation with the other components of the nuclear steam supply system within the prestressed concrete reactor pressure vessel.

scholarly journals Towards the Use of Novel Materials in Shipbuilding: Assessing Thermal Performances of Fire-Doors by Self-Consistent Numerical Modelling

2020 ◽  
Vol 10 (17) ◽  
pp. 5736
Author(s):  
Giada Kyaw Oo D’Amore ◽  
Francesco Mauro ◽  
Alberto Marinò ◽  
Marco Caniato ◽  
Jan Kašpar
Keyword(s):  
Fire Test ◽  
Critical Factor ◽  
Fem Analysis ◽  
Design Guidelines ◽  
Critical Parameters ◽  
Self Consistent ◽  
New Material ◽  
Innovative Materials ◽  
Rock Wool ◽  
Fire Door

Nowadays, fire-doors optimization is approached by using consolidated design guidelines and traditional materials, such as rock wool. Then, selected solution is directly tested in a mandatory fire-test. Unfortunately, few pieces of information could be retrieved either if the test succeeds or fails, which makes both improvements in the design and use of innovative materials difficult. Thus, in this work, a self-consistent finite element method (FEM) analysis is developed and assessed against experimental fire-test results, highlighting the critical parameters affecting the numerical simulations. Using this tool, a new fiberglass-containing foam, with improved acoustic and mechanical properties, as compared to the rock-wool, is studied as a potential insulating material for on-board fire-doors. The assessment of the performance of the new material demonstrates that, contrary to common believe, the effective thermal insulation capacity is not necessarily the critical factor in determining the fire-resistance of a fire-door. Using the validated FEM analysis, it has been proven that the reduction of the thermal bridges originated at the door edges allows, firstly, for the attainment of a fire-door 37% thinner and 61% lighter with respect to a traditional one, and, secondly, the use of new material as insulator in fire-doors that, even if less thermally capable, could improve other properties of the door, as an example its soundproofing.

GAMING EXPERIENCE ON THE MOBITOP SYSTEM: A COLLOCATED AD-HOC COLLABORATION SYSTEM

2016 ◽  
Vol 78 (9-3) ◽  
Author(s):  
Teo Rhun Ming ◽  
Ong Beng Liang ◽  
Noris Mohd Norowi ◽  
Evi Indriasari Mansor ◽  
Prasenjit Dey ◽  
...  
Keyword(s):  
Ad Hoc ◽  
Design Guidelines ◽  
Mobile Systems ◽  
Mobile System ◽  
System A ◽  
Interactive Display ◽  
Present Design ◽  
Collaborative Game ◽  
Ad Hoc Collaboration ◽  
To Come

This paper presents the study on the mobiTop system- a collocated multi-mobile system. The mobiTop system allows users to come together with their mobile devices in an ad-hoc manner to create one seamless and extended interactive display surface. The collocated multi-mobile system allows a group of people to play digital games together in an impromptu manner without having to buy an interactive tabletop equipment. This study investigates the user experience and system design of a collocated multi-mobile system when users play a collaborative game-based application using the mobiTop system. The findings show that the extended screen size of the mobiTop system enhanced the collaborative experience of the users. This study also highlights several design considerations to further improve such systems such as employing a faster network configuration, reducing the bezel effect, catering for dynamic device movements and making the object of interest more prominent and visible. With this understanding, this study present design guidelines to help designers create digital game-based multi-mobile systems for ad-hoc collaboration.

Phone-Based Interfaces: Research and Guidelines

1992 ◽  
Vol 36 (14) ◽  
pp. 1051-1055 ◽  
Author(s):  
Robert M. Schumacher
Keyword(s):  
Design Guidelines ◽  
Information Capacity ◽  
Limited Information ◽  
Input Output ◽  
Future Directions ◽  
Output Device ◽  
Computer Input ◽  
Present Design ◽  
Audio Output ◽  
The U.S

The telephone is the most ubiquitous computer input/output device with over 200 million units in the U.S. Thousands of applications – from airline reservations to zoo schedules – employ audio output and touch-tone input to control the flow and content of information. Because of the limited information capacity of the telephone, designing useful and usable phone-based interfaces presents a strong challenge to the designer. This paper will focus on the strengths and weaknesses of phone-based interfaces, present design guidelines, and discuss future directions.

scholarly journals Improving the Sustainability of the Manufacturing Process by Constructively Optimizing the Parts “Transition Type Fitting”

2019 ◽  
Vol 11 (19) ◽  
pp. 5450
Author(s):  
Dobrotă ◽  
Rotaru ◽  
Nicolescu ◽  
Marin
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Tensile Stress ◽  
Manufacturing Process ◽  
Fem Analysis ◽  
Sustainability Analysis ◽  
New Type ◽  
The Cost ◽  
Transition Type ◽  
Type Of Transition

Transition type fittings are components often used in the transport facilities of fluid, and which allow the passage from a polyethylene (PE) pipe to a metal pipe. Within the paper, there was carried out a sustainability analysis of the manufacturing process for four types of existing transition fittings, and based upon the findings, there was proposed another type of transition fitting. For this new type of transition fitting, both a sustainability analysis and a finite element method (FEM) analysis were performed. Thus, based upon the analysis, there was found that the new constructive variant of transitional fitting is much more sustainable in the sense that the cost of processing has decreased from 0.77 Euros/part to 0.20 Euros/part, and this proposed transition fitting is resistant to tensile stress at a force of 25,800 N, a very large force that shows that the adopted assembly, for this new type of transition fitting will not yield during the operation.

FEM Analysis of Thermal Stresses in Advanced Electronic Packages

1998 ◽  
Vol 516 ◽  
Author(s):  
Sven Rzepka ◽  
Matt A. Korhonen ◽  
Che-Yu Li ◽  
Ekkehard Meusel
Keyword(s):  
Finite Element ◽  
Flip Chip ◽  
Thermal Stresses ◽  
Low Cost ◽  
Fem Analysis ◽  
Design Guidelines ◽  
Material Behavior ◽  
General Tendency ◽  
Element Analysis ◽  
Chip Size

AbstractFollowing the general tendency of downsizing in microelectronic packages, the interposing layer between silicon chip and organic board is constantly reduced while the differences in thermal expansion stay constant. Consequently, thermal stresses have become the most important reliability concern in advanced packages. Finite element analysis is known as an effective way of theoretically studying the mechanical situation in multi-component systems with complex material behavior. The paper presents results of finite element simulations that provide practical guidance for design, process and material developments of chip size packaging (CSP), flip chip (FC), and direct chip attach (DCA) modules. Using realistic and efficient models, a low-cost CSP concept is assessed, the effects of underfill, underfill imperfections, and underfill defects on the reliability of FC modules are studied, and an optimum set of mechanical properties for underfill materials is proposed. Finally, reliability risk factors in DCA modules are identified and preliminary design guidelines are given.

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