DEVELOPMENT OF SMART STRUCTURE SYSTEMS FOR HELICOPTER VIBRATION AND NOISE CONTROL

2007 ◽  
Vol 31 (1) ◽  
pp. 39-56 ◽  
Author(s):  
Y. Chen ◽  
V. Wickramasinghe ◽  
D. G. Zimcik
Keyword(s):  
Noise Control ◽  
National Research Council ◽  
Smart Structure ◽  
Ride Quality ◽  
Vibration Load ◽  
Cabin Noise ◽  
Acoustic Control ◽  
Control Technologies ◽  
Helicopter Vibration

Helicopters are susceptible to high vibratory loads, excessive noise levels and poor flight stability compared to fixed-wing aircraft. The multidisciplinary nature of helicopter structures offers many opportunities for the innovative smart structure technology to improve helicopter performance. This paper provides a review of smart structures research at the National Research Council Canada for helicopter vibration and cabin noise control applications. The patented Smart Spring approach is developed to vary the blade impedance properties adaptively to reduce the vibratory hub loads transmitted to the fuselage by vibration reduction at the source. A smart gearbox strut and active structural acoustic control technologies are investigated to suppress the vibration and tonal gear meshing noise into the cabin either by modifying the vibration load transmission path, or weakening the coupling between exterior and cabin acoustic fields. Two adaptive seat mount concepts are proposed to reduce the vibration of the aircrew directly to improve ride quality of the vehicle.

scholarly journals Reviewer Acknowledgements for Journal of Plant Studies, Vol. 6, No. 2

2017 ◽  
Vol 6 (2) ◽  
pp. 108
Author(s):  
Joan Lee
Keyword(s):  
National Research Council ◽  
University Of Virginia ◽  
University Of Mississippi ◽  
Application Form ◽  
National Education ◽  
Agricultural Experiment ◽  
University Of Florence ◽  
Academy Of Sciences ◽  
E Mail

Journal of Plant Studies wishes to acknowledge the following individuals for their assistance with peer review of manuscripts for this issue. Their help and contributions in maintaining the quality of the journal are greatly appreciated.Journal of Plant Studies is recruiting reviewers for the journal. If you are interested in becoming a reviewer, we welcome you to join us. Please find the application form and details at http://www.ccsenet.org/reviewer and e-mail the completed application form to [email protected] for Volume 6, Number 2Ahmed Ghannam, University of Strasbourg, FranceAlfredo Benavente, Consejería de Agricultura, Pesca y Medioambiente, SpainAmi Lokhandwala, University of Mississippi, Department of Biology, USABingcheng Xu, Chinese Academy of Sciences and Ministry of Water Resources, ChinaChrystian Iezid Maia e Almeida Feres, Tocantins Federal University, BrazilEstelle Dumont, université Aix-Marseille, FranceHoma Mahmoodzadeh, Department of Biology, Mashhad Branch, Islamic Azad University, Mashhad, IranKhyati Hitesh Shah, Stanford University, United StatesKinga Kostrakiewicz-Gieralt, Institute of Botany, Jagiellonian University, PolandKonstantinos Vlachonasios , Aristotle University of Thessaloniki, School of Biology, GreeceMartina Pollastrini, University of Florence, ItalyMassimo Zacchini, National Research Council of Italy (CNR), ItalyMelekber Sulusoglu, Arslanbey Vocational School Kocaeli University, TurkeyMohamed Trigui, Sfax Preparatory Engineering Institute and CBS, TunisiaRajiv Ranjan, T. P. Varma College, IndiaRajnish Sharma, Dr YS Parmar University of Horticulture & Forestry, Solan (HP), IndiaRakesh Ponnala, Zoetis Inc, United StatesRocío Deanna, Instituto Multidisciplinario de Biología Vegetal, ArgentinaSaid Laarabi, University Mohammed V/Ministry of National Education, MoroccoSlawomir Borek, Adam Mickiewicz University, PolandSuheb Mohammed, University of Virginia, United StatesTomoo misawa, Donan Agricultural Experiment Station, Hokkaido Research Organization, Japan

scholarly journals Effect of the turning characteristics of underfloor wheel lathes on the evolution of wheel polygonisation

2018 ◽  
Vol 233 (5) ◽  
pp. 479-488 ◽  
Author(s):  
Dabin Cui ◽  
Boyang An ◽  
Paul Allen ◽  
Ruichen Wang ◽  
Ping Wang ◽  
...  
Keyword(s):  
Fourth Order ◽  
High Speed ◽  
Higher Order ◽  
Ride Quality ◽  
Sustained Use ◽  
High Speed Trains ◽  
Cut Quality ◽  
Multiple Unit ◽  
Component Failures

During both running and wheel cut operations, wheels of railway vehicles and the friction rollers that support and drive the wheelset on a typical wheel cut lathe are subject to wear and hence are likely to develop out-of-round characteristics after sustained use. The resulting out-of-round wheels can significantly affect the ride quality and can potentially increase the incidence of fatigue-related component failures due to the resulting higher intensity loading cycles. Furthermore, the corresponding out-of-round characteristics of the lathe's friction rollers will continue to degrade the subsequent cut quality of wheels. For the analysis of the out-of-round characteristics caused by an underfloor wheel lathe used for the high-speed trains in China, a mathematical model based on a typical electric multiple unit (EMU) vehicle's wheelsets and their interactions with the wheel lathe friction rollers was established. Factors influencing the cut quality of the wheels, including the number of cuts, eccentricity forms of the friction rollers and the longitudinal spacing of the two rollers, have been analysed. The results show that two cuts can effectively remove the higher order polygon on the wheel surface. The eccentricity and phase angle of the friction rollers have no influence on the cut quality of higher order polygons, whereas they are the primary cause for the fourth-order polygons. The severity of the fourth-order polygon depends on the level and the phase of the eccentricity of the friction rollers. The space of the two rollers can also significantly affect the cut quality. Obtaining the theoretical and practical value for the maintenance of polygonised wheels using the underfloor lathe is the main outcome of this study.

scholarly journals Field verification of a new asphalt compactor, AMIR

1991 ◽  
Vol 18 (3) ◽  
pp. 465-471 ◽  
Author(s):  
Otto J. Svec ◽  
A. O. Abd El Halim
Keyword(s):  
Key Words ◽  
Laboratory Testing ◽  
Research Council ◽  
Joint Venture ◽  
National Research Council ◽  
Field Trials ◽  
Full Scale ◽  
Field Verification ◽  
Asphalt Mix

A prototype of a new asphalt compactor termed "asphalt multi-integrated roller (AMIR)" was built as a joint venture between the National Research Council of Canada (NRC) and a Canadian manufacturer, Lovat Tunnel Equipment, Inc. The purpose of this project was to prove this new compaction concept in a full-scale environment. This paper describes one of the field trials carried out on the campus of the NRC and reports the results quantifying the quality of the AMIR compaction. Key words: compactor, asphalt mix, field trials, laboratory testing.

scholarly journals Design of Novel BELBIC Controlled Semi-Active Suspension and Comparative Analysis with Passive and PID Controlled Suspension

2021 ◽  
Vol 18 (5) ◽  
Author(s):  
Pankaj SHARMA ◽  
Vinod KUMAR
Keyword(s):  
Human Body ◽  
Degrees Of Freedom ◽  
Active Suspension ◽  
Driver Model ◽  
Ride Quality ◽  
Body Parts ◽  
Hybrid Techniques ◽  
Design Engineers ◽  
Mass Displacement

Passenger comfort, quality of ride, and handling have broughta lot of attention and concern toautomotive design engineers. These 2 parameters must have optimum balance as they have an inverse effect on each other. Researchers have proposed several approaches and techniques like PID control, fuzzy approach, GA, techniques with inspiration from nature and hybrid techniques to attain the same. A new controller based on the learning behavior of the human brain has been used for the control of semi-active suspension in this study. The controller is known as the Brain Emotional Learning-Based Intelligent Controller (BELBIC). A one-fourth model of car along with the driver model having 6 degrees of freedom (DOF) wasmodeled and simulated. The objective of the studywasto analyze the performance of the proposed controller for improving the dynamic response of the vehicle model coupled with complex biodynamic models of the human body as a passenger, making the whole dynamic system very complex to control. The performance wasanalyzed based on percentage reduction in the overshoot of the vehicle’s sprung mass as well as different human body parts when subjected to road disturbances. The proposed controller performance wascompared with the PID controller, widely used in semi-active suspension. The simulation results obtained for BELBIC controlled system for circular road bump showed that the overshoot of passenger head and body wasreduced by 18.84 and 18.82 %, respectively and reduction for buttock and leg displacement was18.87 %. The vehicle’s seat and sprung mass displacement displayedan improvement of 18.90 and 18.51 %. The overshoot of passenger's head and body displacement wasimproved by 19.79and 19.62 %,respectively, whereas improvement for buttock & leg, vehicle’s seat, and sprung mass displacement were19.81, 20.00, and 20.49 % against trapezoidal speed bump. The PID controlled suspension disclosed an improvement of 8.74, 8.53, 8.75, 11.11, 14.75 % against circular bump and 10.72, 10.33, 10.73, 11.11 and 11.75 % against trapezoidal bump for overshoot reduction of passenger head, body, buttock & leg, vehicle’s seat and sprung mass displacement, respectively. The proposed BELBIC controlled semi-active suspension outperformed the widely used PID controlled semi-active suspension and indicated asignificant improvement in the ride quality of the vehicle.

scholarly journals Multicriterial Evaluation of the Transport and Logistic System of the Moscow Region

2021 ◽  
Vol 334 ◽  
pp. 02029
Author(s):  
Vasily Demin ◽  
Alexey Terentyev
Keyword(s):  
Radio Frequency ◽  
Control Method ◽  
Complex Structure ◽  
Moscow Region ◽  
Logistics System ◽  
System Parameters ◽  
Complex Problems ◽  
Control Technologies ◽  
And Control

The article deals with the direction of solving complex problems of interaction between the elements of the transport and logistics system of the Moscow region as a complex structure of management methods in multi-criteria systems and technologies for monitoring the quality of processes. The control method should optimize the system parameters, and control technologies (radio frequency cargo identification) implement feedback in the system.

Ride Quality of Autorack Cars

1978 ◽  
Vol 100 (2) ◽  
pp. 171-180
Author(s):  
L. P. Greenfield ◽  
L. A. McLean ◽  
E. J. Wolf
Keyword(s):  
Ride Quality
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