Sea Motion Simulation, Very Low Frequency Vibration, and Motion Sickness

1976 ◽  
Vol 20 (20) ◽  
pp. 462-462
Author(s):  
Michael E. McCauley
Keyword(s):  
Motion Sickness ◽  
Degrees Of Freedom ◽  
Low Frequency ◽  
Vertical Motion ◽  
Basic Research ◽  
Future Research ◽  
Naval Research ◽  
Low Frequency Vibration ◽  
Office Of Naval Research ◽  
Linear Oscillation

The office of Naval Research/Human Factors Research (ONR/HFR) Motion Generator was designed with three degrees of freedom (heave, pitch, and roll) to simulate the motion of an air-sea craft in varying ocean conditions through Sea State 5. Recent upgrading of the device has provided the capability for simulating the motion of advanced design sea craft as well as certain aspects of vertical motion common to land, sea, and air vehicles. Since 1968, the simulator has been used for investigation of the following topics: (1) basic research to provide equations for the prediction of motion sickness incidence based on parameters of vertical linear oscillation, (2) crew performance during simulated motion of two types of proposed naval vessels, and (3) evaluation of the efficacy of antimotion sickness medications in alleviating the symptoms of motion sickness. This simulator provides the opportunity for future research on the effects of motion on physiological and psychological processes as well as task performance.

US Office of Naval Research Arctic Research Laboratory, Point Barrow, Alaska

Polar Record ◽  
1967 ◽  
Vol 13 (85) ◽  
pp. 421-423 ◽  
Author(s):  
M. E. Britton
Keyword(s):  
Research Laboratory ◽  
Basic Research ◽  
Government Support ◽  
The Arctic ◽  
Naval Research ◽  
Research Facility ◽  
Scientific Enterprise ◽  
Office Of Naval Research ◽  
General Scientific ◽  
Arctic Coast

The Arctic Research Laboratory (ARL) is a year-round, continuing, basic research facility, funded by the Office of Naval Research (ONR), US Department of Navy, and located in lat 71° 21'N, long 156° 46'W, near Point Barrow, on the Arctic coast of Alaska. It was established in 1947 not, as could be reasonably expected, only to further investigations of immediate and practical use to the Navy, but also to support work of purely general scientific interest. Scientists from other countries were also invited to make use of its facilities. ARL represents a laudable co-operation between government support and private scientific enterprise.

Direct Digital Additive Manufacturing and Cyber-Enabled Manufacturing Systems

2012 ◽  
Author(s):  
Khershed P. Cooper
Keyword(s):  
Additive Manufacturing ◽  
Manufacturing Systems ◽  
Complex Geometry ◽  
Basic Research ◽  
Naval Research ◽  
Physical Processes ◽  
Physical Systems ◽  
Office Of Naval Research ◽  
And Control ◽  
Manufacturing Problems

The technology of direct digital additive manufacturing (D2AM) has received considerable attention in recent months. Several government agencies and commercial interests are planning to explore D2AM to find solutions to manufacturing problems. The attraction of D2AM is the benefit of rapidly producing without fixtures or tools or human intervention customized objects of complex geometry not possible by traditional methods. The interest in D2AM ranges from fabrication of critical, high value aerospace metallic components to fabrication of objects having an organic look or as nature would have intendedi. For D2AM to be commercially accepted, it must reliably and predictably make products. It must achieve consistency in reproducibility across relevant D2AM methods. The Office of Naval Research (ONR) has launched a new basic research program, known as Cyber-enabled Manufacturing Systems (CeMS). The long-range goal of the program is to achieve the level of control over D2AM processes for industrial acceptance and wide-use of the technology. This program will develop measuring, sensing and control models and algorithms for D2AM by harnessing principles underpinning cyber-physical systems (CPS) and fundamentals of physical processes. This paper describes the challenges facing D2AM and the CeMS program goals to meet them.

Recent Advances in Quasi-Zero-Stiffness Vibration Isolation Systems

2013 ◽  
Vol 397-400 ◽  
pp. 295-303 ◽  
Author(s):  
Fu Niu ◽  
Ling Shuai Meng ◽  
Wen Juan Wu ◽  
Jing Gong Sun ◽  
Wei Hua Su ◽  
...  
Keyword(s):  
Vibration Isolation ◽  
Low Frequency ◽  
Future Research ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Significant Development ◽  
Recent Advances ◽  
Low Frequency Vibration ◽  
Future Research Directions ◽  
Isolation Systems

The quasi-zero-stiffness vibration isolation system has witnessed significant development due to the pressing demands for low frequency and ultra-low frequency vibration isolation. In this study, the isolation theory and the characteristic of the quasi-zero-stiffness vibration isolation system are illustrated. Based on its implementation mechanics, a comprehensive assessment of recent advances of the quasi-zero-stiffness vibration isolation system is presented. The future research directions are finally prospected.

scholarly journals Low frequency vibration influencing motion sickness in trains.

2003 ◽  
Vol 39 (6) ◽  
pp. 267-274
Author(s):  
Hiroaki SUZUKI ◽  
Hiroaki SHIROTO ◽  
Kazuhiko TEZUKA
Keyword(s):  
Motion Sickness ◽  
Low Frequency ◽  
Low Frequency Vibration

Prediction of Resistance and Self-Propulsion Characteristics of a Full-Scale Naval Ship by CFD-Based GEOSIM Method

2020 ◽  
pp. 1-16 ◽  
Author(s):  
Cihad Delen ◽  
Ugur Can ◽  
Sakir Bal
Keyword(s):  
Degrees Of Freedom ◽  
Full Scale ◽  
The Self ◽  
Body Motion ◽  
Ship Motions ◽  
Naval Research ◽  
Propulsion Performance ◽  
Office Of Naval Research ◽  
Naval Ship ◽  
Computational Fluid Dynamics Cfd

Resistance and self-propulsion characteristics of a naval ship at full scale have been investigated by using Telfer’s GEOmetrically SIMilar (GEOSIM) method based on the computational fluid dynamics (CFD) approach. For this purpose, first, the resistance forces of the Office of Naval Research Tumblehome (ONRT) hull have been computed at different three model scales by using the overset mesh technique. The full-scale resistance and nominal wake fraction of the ONRT hull have been estimated by using Telfer’s GEOSIM method. Resistance and nominal wake fraction have then been compared with those of CFD at full scale. Later, the self-propulsion characteristics of the ONRT hull have been examined using Telfer’s GEOSIM method based on the CFD approach. Self-propulsion factors at the full-scale hull have been predicted by using the SST k-ω turbulence model to involve 2-degrees of freedom ship motions (heave and pitch). Rotational motion of the propeller has also been simulated by using the rigid body motion technique. The results calculated by Telfer’s GEOSIM method and the 1978 International Towing Tank Conference (ITTC) extrapolation technique have been compared with each other and discussed with those of the CFD approach at full scale. It was found that the full-scale results (both resistance and self-propulsion factors) predicted by Telfer’s GEOSIM method are closer to those of the CFD approach than those of the 1978 ITTC technique. It can be noted that Telfer’s GEOSIM method is fast, robust, and reliable and can be used as an alternative to the 1978 ITTC method for predicting the self-propulsion performance of a full-scale ship.

Basic research in the Office of Naval Research

Physics Today ◽  
1951 ◽  
Vol 4 (9) ◽  
pp. 17-19
Author(s):  
Dwight E. Gray
Keyword(s):  
Basic Research ◽  
Naval Research ◽  
Office Of Naval Research

A Six Degrees-of-Freedom Vibration Isolation Platform Supported by a Hexapod of Quasi-Zero-Stiffness Struts

2017 ◽  
Vol 139 (3) ◽  
Author(s):  
Jiaxi Zhou ◽  
Kai Wang ◽  
Daolin Xu ◽  
Huajiang Ouyang ◽  
Yingli Li
Keyword(s):  
Degrees Of Freedom ◽  
Vibration Isolation ◽  
Permanent Magnets ◽  
Low Frequency ◽  
Harmonic Balance Method ◽  
Dynamic Responses ◽  
Six Degrees Of Freedom ◽  
Low Frequency Vibration ◽  
Force Moment ◽  
Vibration Isolation Performance

A platform supported by a hexapod of quasi-zero-stiffness (QZS) struts is proposed to provide a solution for low-frequency vibration isolation in six degrees-of-freedom (6DOFs). The QZS strut is developed by combining a pair of mutually repelling permanent magnets in parallel connection with a coil spring. Dynamic analysis of the 6DOFs QZS platform is carried out to obtain dynamic responses by using the harmonic balance method, and the vibration isolation performance in each DOF is evaluated in terms of force/moment transmissibility, which indicates that the QZS platform perform a good function of low-frequency vibration isolation within broad bandwidth, and has notable advantages over its linear counterpart in all 6DOFs.

Low Frequency Vibration Consideration in Tool-Path Computation of Two-Link Serial Manipulator for Improved Accuracy

2014 ◽  
Author(s):  
Denis Juschanin ◽  
Fisseha M. Alemayehu ◽  
Stephen Ekwaro-Osire
Keyword(s):  
Mode Coupling ◽  
Tool Path ◽  
Industrial Robot ◽  
Research Question ◽  
Low Frequency ◽  
Industrial Robots ◽  
Machining Process ◽  
Future Research ◽  
Low Frequency Vibration ◽  
Path Computation

Industrial robots are flexible and cost-efficient tools for a multitude of applications such as, polishing, grinding, deburring, and welding. However, their utilization in machining tasks is currently limited due to insufficient position accuracy. This study aims to answer the research question: ‘Does including low frequency vibrations (mode coupling chatter) in tool path computation improve accuracy?’ For this purpose, the current paper focuses on setting-up a robust and flexible simulation framework. The framework implements a predictive cutting force method into a multibody dynamic (MBD) model of an industrial robot. The framework is structured in an extendable fashion for future research tasks. Future work will include mode coupling chatter into the MBD model to help mitigate the effects of chatter in robotic machining process, which in turn will increase tool-path accuracy.

scholarly journals Effects of Low Frequency Vibration on Train Motion Sickness

2005 ◽  
Vol 46 (1) ◽  
pp. 35-39 ◽  
Author(s):  
Hiroaki SUZUKI ◽  
Hiroaki SHIROTO ◽  
Kazuhiko TEZUKA
Keyword(s):  
Motion Sickness ◽  
Low Frequency ◽  
Low Frequency Vibration
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