Semi-Active Magnetorheological Helicopter Crew Seat Suspension for Vibration Isolation

Hiemenz, Gregory J.; Hu, Wei; Wereley, Norman M.

doi:10.2514/1.32736

Cited by 91 publications

(49 citation statements)

References 10 publications

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“…Although other efforts have been made in order to reduce vibrations in other elements of helicopters such as passengers' seats (Hiemenz et al 2008), this section of the chapter is focused in reducing vibrations when using sensor devices. Due to their great maneuverability in open environments where other aerial vehicles are more difficult to be used, they represent a very convenient type of vehicle to be employed for certain tasks.…”

Section: Semi-active Dampers For Vibration Control In Autonomous Helimentioning

confidence: 99%

Fuzzy Modeling and Control: Theory and Applications

Mata¹,

Marichal²,

Jimnez³

2014

Atlantis Computational Intelligence Systems

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Aims and scope of the seriesThe series 'Atlantis Computational Intelligence Systems' aims at covering state-of-the-art research and development in all fields where computational intelligence is investigated and applied. The series seeks to publish monographs and edited volumes on foundations and new developments in the field of computational intelligence, including fundamental and applied research as well as work describing new, emerging technologies originating from computational intelligence research. Applied CI research may range from CI applications in the industry to research projects in the life sciences, including research in biology, physics, chemistry and the neurosciences.All books in this series are co-published with Springer.For more information on this series and our other book series, please visit our website at: www.atlantis-press.com/publications/books. This book is published under the Creative Commons Attribution-Non-commercial license, meaning that copying, distribution, transmitting and adapting the book is permitted, provided that this is done for non-commercial purposes and that the book is attributed. This book, or any parts thereof, may not be reproduced for commercial purposes in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system known or to be invented, without prior permission from the Publisher.Printed on acid-free paper ForewordAlmost half a century has passed since the publication of the seminal paper by Prof. Lotfi A. Zadeh. Fifty years that have witnessed an impressive growth of fuzzy systems from both the theoretical and applied points of view. Impressive growth and at the same time following an unforeseen way, since as Prof. Zadeh has said many times, his expectations when writing his first paper on fuzzy sets in 1965 were that fuzzy sets would find its main applications in the realm of humanistic systems (economics, linguistics, psychology, etc.). Now the reality is that most of the success of fuzzy systems research (at least in its initial decades) was related to its application to mechanistic instead of humanistic systems. This book concentrates on modeling and control of mechanistic systems, as can be seen when reading the Table of Contents, first considering important theoretical aspects and then showing its application to quite interesting real-world problems.Any book on fuzzy modeling and control is somehow a tribute to those who paved the way for the topic. In this case, we need to consider three key persons and three related milestones in the history of fuzzy sets. First, the already mentioned Prof. Zadeh and his 1973 paper ''Outline of a New Approach to the Analysis of Complex Systems and Decision Processes,'' IEEE Transactions on Systems, Man, and Cybernetics 3: 28-44 (1973), the paper where concepts as linguistic variable and fuzzy if-then rules took form, and at the same time, the paper that triggered the second hint in the road to build up the theory of fuzzy modeling and control. Ab...

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Section: Semi-active Dampers For Vibration Control In Autonomous Helimentioning

confidence: 99%

Fuzzy Modeling and Control: Theory and Applications

Mata¹,

Marichal²,

Jimnez³

2014

Atlantis Computational Intelligence Systems

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“…With passive seat suspensions, the vibration attenuation performance is limited due to the fixed characteristics of the suspension elements and, thus, they are only effective over a limited frequency range. In contrast, the suspension characteristics of semi-active systems are controlled by using adjustable suspension elements, such as magnetorheological dampers (MR) [2] or electro-rheological (ER) dampers [3]. Whilst, semi-active systems are safe, cost-effective and require low power consumption, the isolation performance is still limited, as a semi-active suspension can dissipate energy and re-distribute this within the system but cannot add energy [4].…”

Section: Introductionmentioning

confidence: 99%

An Active Seat Controller with Vehicle Suspension Feedforward and Feedback States: An Experimental Study

2018

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Active seat suspensions can be used to reduce the harmful vertical vibration of a vehicle's seat by applying an external force using a closed loop controller. Many of the controllers found in the literature are difficult to implement practically, because they are based on using unavailable or difficult and costly measurements. This paper presents both simulation and experimental studies of five novel, simple, and cost-effective control strategies to be used for an active seat suspension in order to improve ride comfort at low frequencies below 20 Hz. These strategies use available and measurable feedforward (preview) information states from the vehicle secondary suspension, as well as feedback states from the seat suspension, together with gains optimised to minimise the occupant vibration. The gains were optimised using a genetic algorithm (GA), with a fitness function based on the seat effective amplitude transmissibility (SEAT) factor. Constraints on the control force and the seat suspension stroke were also included in the optimisation algorithm. Simulation and laboratory experimental tests were carried out to assess the performance of the proposed controllers according to the ISO 2631-1 standard, in both the frequency and time domains with a range of different road profiles. The experimental tests were performed using a multi-axis simulation table (MAST) and a physical active seat suspension configured as a hardware-in-loop (HIL) simulation with a virtual linear quarter vehicle model (QvM). The results demonstrate that the proposed controllers substantially attenuate the vertical vibration at the driver's seat compared with both a passive and a proportional-integral-derivative (PID) active seat suspension and thus improve ride comfort together with reducing vibration-linked health risks. Moreover, experimental results show that employing both feedforward information and feedback vehicle body and seat acceleration signals in the controller provides isolation performance gains of up to 19.5 dB over the human body sensitivity frequency range and improves the ride comfort in terms of the SEAT factor and the weighted root mean square (RMS) seat acceleration by at least 25% when compared with a passive system, irrespective of vehicle forward speed.

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“…Magnetorheological energy absorbers (MREAs) have been successfully implemented in semiactive crashworthy systems to protect occupants against impact, shock and blastloads, especially to protect the lumbar region of the human spine [1][2][3]. Shear rates in these MREAs typically range up to 25,000 s À 1 or higher.…”

Section: Introductionmentioning

confidence: 99%