scholarly journals Car Soundproof Improvement Through an SMA Adaptive System

2018 ◽  
Author(s):  
Salvatore Ameduri ◽  
Angela Brindisi ◽  
Monica Ciminello ◽  
Antonio Concilio ◽  
Vincenzo Quaranta ◽  
...  
Keyword(s):  
Smart Materials ◽  
Adaptive System ◽  
Numerical Models ◽  
Design Parameters ◽  
Joule Effect ◽  
Speed Increase ◽  
Closure Operations ◽  
Working Principle ◽  
High Level ◽  
Final System

The work at hand focuses on an adaptive system aimed at improving the soundproof performance of car door seals at specific working regimes (cruise), without interfering with the conventional open-closure operations. The idea addresses the necessity of increasing the seal effectiveness, jeopardized by aerodynamic actions more and more important as the speed increase, generating a pressure difference between the internal and the external filed, in the direction of opening the door. To recover this effect, an expanding mechanism was integrated within the seal cavity, driven by an SMA actuator. The material was activated (heated) by Joule effect; its compactness, intrinsic of smart materials, contributed to arrive to a final system characterized by a high level of integrability (expanding cells). In this paper, the development process is described together with the verification activity, aimed at proving the functionality of the realized device. Starting from the industrial requirements, the most appropriate solution was identified highlighting the working principle and the main design parameters involved. Then, the envisaged system was designed and its executive digital mock up (CAD) was released. Prototyping and laboratory validation showed the reliability of the numerical models and the associated predictions. On this basis, the integration task within the actual reference car was faced. To demonstrate the isolation effect of the proposed system, an experimental campaign was finally organized in an anechoic room, achieving significant results on the concept value.

scholarly journals Car Soundproof Improvement through an SMA Adaptive System

Actuators ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 88 ◽  
Author(s):  
Salvatore Ameduri ◽  
Angela Brindisi ◽  
Monica Ciminello ◽  
Antonio Concilio ◽  
Vincenzo Quaranta ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Adaptive System ◽  
System Development ◽  
Numerical Models ◽  
Modular System ◽  
Design Parameters ◽  
Joule Effect ◽  
Acoustic Insulation ◽  
Opening And Closing ◽  
Aided Design

The work at hand focuses on an adaptive system aimed at improving the soundproof performance of car door seals at specific regimes (cruise), without interfering with the conventional opening and closing operations. The idea addresses the necessity of increasing seal effectiveness, jeopardized by aerodynamic actions that strengthen as the speed increases, generating a growing pressure difference between the internal and the external field in the direction of opening the door, and then deteriorating the acoustic insulation. An original expansion mechanism driven by a shape memory alloy (SMA) wire was integrated within the seal cavity to reduce that effect. The smart material was activated (heated) by using the Joule effect; its compactness contributed to the realization of a highly-integrable and modular system (expanding cells). In this paper, the system development process is described together with the verification and validation activity, aimed at proving the functionality of the realized device. Starting from industrial requirements, a suitable solution was identified by considering the basic phenomenon principle and the allowable design parameters. The envisaged system was designed and its executive digital mock-up (CAD, computer-aided design) was released. Prototyping and laboratory tests showed the reliability of the developed numerical models and validated the associated predictions. Finally, the system was integrated within the reference car. To demonstrate the insulation effect, the experimental campaign was carried out in an anechoic room, achieving significant results on the concept value.

Modeling drive wheels of hoisting machines with rubber cables

2020 ◽  
pp. 105-114
Author(s):  
V. E. Perekutnev ◽  
V. V. Zotov
Keyword(s):  
Stress State ◽  
Safety Factor ◽  
Numerical Models ◽  
Design Parameters ◽  
Potential Range ◽  
Capital Costs ◽  
Reducing Gear ◽  
Reduce Risk ◽  
Steel Cables ◽  
Sidewall Surface

Upgrading of hoisting machines aims to improve their performance, to reduce risk of accidents, and to cut down operational and capital costs. One of the redesign solutions is replacement of steel cables by rubber cables. This novation can extend life of pulling members, decrease diameters of drive and guide wheels and, consequently, elements of the whole hoisting machines: rotor, reducing gear, motor. This engineering novation needs re-designing of hoisting machines; thus, the new design should be validated, in particular, strength characteristics of the machine members. This article considers a drive wheel of a hoisting machine with a pulling belt. In order to justify the potential range of design parameters with regard to safety factor, the numerical models of different-design drive wheels are developed and their operation with pulling belt (rubber cable) is simulated in the SolidWorks environment. The data on the stress state of the wheel elements are analyzed, the most loaded points are identified, and the maximal stresses on the sidewall surface and in the spokes of wheels of different designs are plotted.

scholarly journals Corrosion of ternary borosilicate glass in acidic solution studied in operando by fluid-cell Raman spectroscopy

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Christoph Lenting ◽  
Thorsten Geisler
Keyword(s):  
Raman Spectroscopy ◽  
Nuclear Waste ◽  
Numerical Models ◽  
Adsorbed Water ◽  
Corrosion Mechanism ◽  
Borosilicate Glasses ◽  
Long Term Storage ◽  
In Operando ◽  
High Level ◽  
Fluid Cell

AbstractFluid-cell Raman spectroscopy is a space and time-resolving application allowing in operando studies of dynamic processes during solution–solid interactions. A currently heavily debated example is the corrosion mechanism of borosilicate glasses, which are the favoured material for the immobilization of high-level nuclear waste. With an upgraded fluid-cell lid design made entirely from the glass sample itself, we present the polymerization of the surface alteration layer over time in an initially acidic environment, including the differentiation between pore and surface-adsorbed water within it. Our results support an interface-coupled dissolution-precipitation model, which opposes traditional ion-exchange models for the corrosion mechanism. A sound description of the corrosion mechanism is essential for reliable numerical models to predict the corrosion rate of nuclear waste glasses during long-term storage in a geological repository.

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 A Shock Mitigation of Pedestrian-Vehicle Impact Using Active Hood Lift System: Deploying Time Investigation

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Tae-Hoon Lee ◽  
Gun-Ha Yoon ◽  
Seung-Bok Choi
Keyword(s):  
Response Time ◽  
Design Parameters ◽  
Passenger Vehicle ◽  
Governing Equations ◽  
Total Response Time ◽  
Shock Mitigation ◽  
Vehicle Impact ◽  
Driving Speed ◽  
Working Principle ◽  
Principal Design

This paper investigates the deploying time (or response time) of an active hood lift system (AHLS) of a passenger vehicle activated by gunpowder actuator. In this work, this is accomplished by changing principal design parameters of the latch part mechanism of the hood system. After briefly introducing the working principle of the AHLS operated by the gunpowder actuator, the governing equations of the AHLS are formulated for each different deploying motion. Subsequently, using the governing equations, the response time for deploying the hold lift system is determined by changing several geometric distances such as the distance from the rotational center of the pop-up guide to the point of the latch in the axial and vertical directions. Then, a comparison is made of the total response time to completely deploy the hood lift system with the existing conventional AHLS and proposed AHLS. In addition, the workable driving speed of the proposed AHLS is compared with the conventional one by changing the powder volume of the actuator.

scholarly journals Evaluation of Static Mapping for Dynamic Space-Shared Multi-task Processing on FPGAs

2021 ◽  
Author(s):  
Umar Ibrahim Minhas ◽  
Roger Woods ◽  
Georgios Karakonstantis
Keyword(s):  
High Performance ◽  
Design Space Exploration ◽  
Design Space ◽  
System Throughput ◽  
Design Parameters ◽  
Temporal Constraints ◽  
Shared Resources ◽  
Task Processing ◽  
High Level ◽  
Performance Computing

AbstractWhilst FPGAs have been used in cloud ecosystems, it is still extremely challenging to achieve high compute density when mapping heterogeneous multi-tasks on shared resources at runtime. This work addresses this by treating the FPGA resource as a service and employing multi-task processing at the high level, design space exploration and static off-line partitioning in order to allow more efficient mapping of heterogeneous tasks onto the FPGA. In addition, a new, comprehensive runtime functional simulator is used to evaluate the effect of various spatial and temporal constraints on both the existing and new approaches when varying system design parameters. A comprehensive suite of real high performance computing tasks was implemented on a Nallatech 385 FPGA card and show that our approach can provide on average 2.9 × and 2.3 × higher system throughput for compute and mixed intensity tasks, while 0.2 × lower for memory intensive tasks due to external memory access latency and bandwidth limitations. The work has been extended by introducing a novel scheduling scheme to enhance temporal utilization of resources when using the proposed approach. Additional results for large queues of mixed intensity tasks (compute and memory) show that the proposed partitioning and scheduling approach can provide higher than 3 × system speedup over previous schemes.

scholarly journals Synoptic Conditions, Clouds, and Sea Ice Melt Onset in the Beaufort and Chukchi Seasonal Ice Zone

2017 ◽  
Vol 30 (17) ◽  
pp. 6999-7016 ◽  
Author(s):  
Zheng Liu ◽  
Axel Schweiger
Keyword(s):  
Sea Ice ◽  
Numerical Models ◽  
Precipitable Water ◽  
Reanalysis Data ◽  
Cloud Microphysics ◽  
Low Level ◽  
Ice Melt ◽  
Synoptic Conditions ◽  
High Level ◽  
Seasonal Ice Zone

Cloud response to synoptic conditions over the Beaufort and Chukchi seasonal ice zone is examined. Four synoptic states with distinct thermodynamic and dynamic signatures are identified using ERA-Interim reanalysis data from 2000 to 2014. CloudSat and CALIPSO observations suggest control of clouds by synoptic states. Warm continental air advection is associated with the fewest low-level clouds, while cold air advection generates the most low-level clouds. Low-level clouds are related to lower-tropospheric stability and both are regulated by synoptic conditions. High-level clouds are associated with humidity and vertical motions in the upper atmosphere. Observed cloud vertical and spatial variability is reproduced well in ERA-Interim, but winter low-level cloud fraction is overestimated. This suggests that synoptic conditions constrain the spatial extent of clouds through the atmospheric structure, while the parameterizations for cloud microphysics and boundary layer physics are critical for the life cycle of clouds in numerical models. Sea ice melt onset is related to synoptic conditions. Melt onsets occur more frequently and earlier with warm air advection. Synoptic conditions with the highest temperatures and precipitable water are most favorable for melt onsets even though fewer low-level clouds are associated with these conditions.

scholarly journals Design of Biomechanical Legs with a Passive Toe Joint for Enhanced Human-like Walking

2017 ◽  
Vol 14 (2) ◽  
pp. 166 ◽  
Author(s):  
Riadh Zaier ◽  
A. Al-Yahmedi
Keyword(s):  
Design Procedure ◽  
Human Walking ◽  
Human Gait ◽  
Design Parameters ◽  
Sultan Qaboos University ◽  
Motion Trajectories ◽  
Normal Human ◽  
Working Principle ◽  
Mass Spring ◽  
Torsion Springs

This paper presents the design procedure of a biomechanical leg, with a passive toe joint, which is capable of mimicking the human walking. This leg has to provide the major features of human gait in the motion trajectories of the hip, knee, ankle, and toe joints. Focus was given to the approach of designing the passive toe joint of the biomechanical leg in its role and effectiveness in performing human like motion. This study was inspired by experimental and theoretical studies in the fields of biomechanics and robotics. Very light materials were mainly used in the design process. Aluminum and carbon fiber parts were selected to design the proposed structure of this biomechanical leg, which is to be manufactured in the Mechanical Lab of the Sultan Qaboos University (SQU). The capabilities of the designed leg to perform the normal human walking are presented. This study provides a noteworthy and unique design for the passive toe joint, represented by a mass-spring damper system, using torsion springs in the foot segment. The working principle and characteristics of the passive toe joint are discussed.  Four-designed cases, with different design parameters, for the passives toe joint system are presented to address the significant role that the passive toe joint plays in human-like motion. The dynamic motion that is used to conduct this comparison was the first stage of the stance motion. The advantages of the presence of the passive toe joint in gait, and its effect on reducing the energy consumption by the other actuated joints are presented and a comparison between the four-designed cases is discussed.

scholarly journals Localização de nascentes ameaçadas em áreas urbanas: Uma estratégia preventiva de conservação ambiental com auxílio de Modelo Digital do Terreno (MDT)

2021 ◽  
Vol 14 (4) ◽  
pp. 2186-2203
Author(s):  
Bárbara Fernanda da Cunha Tasca ◽  
Fernanda Vieira Xavier ◽  
Auberto José Barros Siqueira
Keyword(s):  
Land Surface ◽  
Numerical Models ◽  
Urban Expansion ◽  
Digital Terrain Model ◽  
Human Occupation ◽  
Public Authorities ◽  
First Order ◽  
Terrain Model ◽  
Drainage Channels ◽  
High Level

Identifying urban headwaters and delimitating their Permanent Preservation Areas (PPA) before its inevitable degradation by the human occupation is essential to guarantee the long-term sustainability of the cities. However, the scarcity of tools for facilitating this purpose prevents public authorities from speeding up their control actions. As headwaters frequently occur near the beginning of first-order drainage channels, it is assumed that their location can be obtained by using numerical models of the land surface. Thus, this study aimed to evaluate and demonstrate the applicability of a Digital Terrain Model (MDT) as an auxiliary tool in the prospecting process in spring fields in the urban area of Cuiabá, MT, Brazil. The methodology consisted of extracting the drainage channels from the modeled area, making it possible to indicate locations for prospecting corresponding to the head regions of the first order channels. The results show that 62,8% of the occurrence of the headwaters were in a 300m radii from the first-order start points. However, it was not possible to issue a conclusive evaluation in 28,6% of the places due to the high level of anthropization. Nevertheless, only in 8,6% of them did not present any water emergence in the surroundings, indicating the effectiveness of this method in guiding the prospection of headwaters in field. We concluded that our procedures are worthful for cities that have detailed altimetric surveys, being especially useful in urban expansion areas, where the preventive character of headwaters conservation is essential.

Analysis of a Pot-Like Ultrasonic Sensor with an Anisotropic Beam Pattern

2010 ◽  
Vol 26 (3) ◽  
pp. 373-384 ◽  
Author(s):  
C.-C. Cheng ◽  
C.-Y. Lin ◽  
J.-H. Ho ◽  
C.-S. Chen ◽  
J. Shieh ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Fourier Transforms ◽  
Numerical Models ◽  
Beam Width ◽  
Ultrasonic Sensor ◽  
Beam Pattern ◽  
Design Parameters ◽  
Far Field ◽  
Vertical Beam ◽  
Vibrating Plate

AbstractWe investigated the design parameters of a compact pot-like ultrasonic sensor which possesses a highly anisotropic beam pattern. As the sensor size is small due to its application constraint, the parameters are thus highly coupled to one another. We analyzed the respective effects of the parameters in the case where there is a vertical beam width reduction. The parameters investigated include resonant frequency, vibrating plate width-expanded angle, and ratio of thickness discontinuity of the vibrating plate. Numerical models developed by combining finite-element analysis and spatial Fourier transforms were adopted to predict the far-field radiating beam pattern of the various design configurations. The displacement distribution of the vibrating plate was measured using a microscopic laser Doppler vibrometer and the far-field pressure beam patterns were measured using a standard microphone in a semianechoic environment. The three configurations we used to validate the simulation model resulted in an H-V ratio of 2.67, 2.68 and 3.13, respectively which all agreed well with the numerical calculations. We found that by increasing the operating resonant frequency from 40kHz to 58kHz, the vertical far-field beam width of an ultrasonic sensor can be reduced by 31.62%. We found that the vertical beam width can be significantly reduced when the ratio of the thickness discontinuity of the vibrating plate decreases from 1 to 0.4 and is incorporated with its optimal width-expanded angle of the vibrating plate. It appears that an ultrasonic sensor with this type of anisotropic beam pattern can be ideally adopted for today's automotive applications.

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