Abstract

This paper presents the experimental and numerical investigation of a single-axis replicate of a patented multi-axis active vibration isolation seat mount. Following the design of the multi-axis system, this single axis vibration isolation mount uses a flexible elastomer support placed in parallel with an electromagnetic actuator. This mount is designed to reduce the N/rev harmonic vibration of a helicopter using a filtered-X least mean square (FXLMS)-based controller. To improve the efficiency of the FXLMS controller for this application, the ISO-2631-1 Wk filter is added. Employing this modified controller, the experimental setup is tested using a payload mass representative of a 95th percentile pilot. The experimental results confirm the effectiveness of the proposed design in canceling the unwanted helicopter vibration, where the active mount effectively reduces the vibration representative of a Bell-412 helicopter by 69.37% (−10.28 dB, g-rms). In order to develop a better understanding of the problem, the system is also modeled from first principles in simulink. The comparison between the nonlinear numerical model and the experimental results demonstrates a good agreement between the two approaches. Moreover, it is shown that the addition of the ISO-2631-1 Wk filter improves the transient performance of the FXLMS controller for the given helicopter vibration profile.

References

1.
Castelo
,
N. B.
, and
Rodriguez
,
E.
,
1999
, “
The Vibroacoustic Disease–An Emerging Pathology
,”
Aviat., Space Environ. Med.
,
70
(
3 Pt 2
), pp.
A1
A6
.https://www.tib.eu/en/search/id/BLSE%3ARN057973018/The-Vibroacoustic-Disease-An-Emerging-Pathology/
2.
Smith
,
S. D.
,
2002
, “
Characterizing the Effects of Airborne Vibration on Human Body Vibration Response
,”
Aviat., Space, Environ. Med.
,
73
(
1
), pp.
36
45
.https://www.tib.eu/en/search/id/olc%3A1618263439/Characterizing-the-Effects-of-Airborne-Vibration/
3.
Delahaye
,
R.-P.
,
Pannier
,
R.
,
Seris
,
H.
,
Auffret
,
R.
,
Carre
,
R.
, and
Mangin
,
H.
,
1970
, “
Physiopathology and Pathology of Affections of the Spine in Aerospace Medicine
,” Advisory Group for Aerospace Research and Development, Neuilly-Sur-Seine, France, Report No.
AGARD-AG-140-70
.https://apps.dtic.mil/dtic/tr/fulltext/u2/713916.pdf
4.
Delahaye
,
R.-P.
,
Auffret
,
R.
,
Doury
,
P.
,
Kleitz
,
C.
, and
Leger
,
A.
,
1982
, “
Physiopathology and Pathology of Spinal Injuries in Aerospace Medicine
,” Advisory Group for Aerospace Research and Development, Neuilly-Sur-Seine, France, Report No.
AGARD-AG-250(ENG)
. https://apps.dtic.mil/dtic/tr/fulltext/u2/a115369.pdf
5.
Pope
,
M.
,
Wilder
,
D.
, and
Magnusson
,
M.
,
1999
, “
A Review of Studies on Seated Whole Body Vibration and Low Back Pain
,”
Proc. Inst. Mech. Eng., Part H
,
213
(
6
), pp.
435
446
.10.1243/0954411991535040
6.
McFarland
,
R. E.
,
1983
, “
The N/Rev Phenomenon in Simulating a Blade-Element Rotor System
,”
NASA TM-84344
.https://www.semanticscholar.org/paper/The-N%2Frev-phenomenon-in-simulating-a-blade-element-Mcfarland/bc55944d77571f1305ef3cb3d268b20ba4
7.
ISO
,
1997
, “
Mechanical Vibration and Shock: Evaluation of Human Exposure to Whole-Body Vibration—Part 1: General Requirements
,” International Organization for Standardization, Geneva, Switzerland, Standard No. ISO 2631-1: (E).
8.
Wickramasinghe
,
V. K.
,
2013
, “
Dynamics Control Approaches to Improve Vibratory Environment of the Helicopter Aircrew
,”
Ph.D. thesis
, Carleton University, Ottawa, ON, Canada.https://curve.carleton.ca/5f5c189e-cd09-4812-8302-5fec92fc134b
9.
Wright Beatty
,
H. E.
,
Law
,
A. J.
,
Thomas
,
J. R.
, and
Wickramasinghe
,
V.
,
2018
, “
Amplified Pilot Head Vibration and the Effects of Vibration Mitigation on Neck Muscle Strain
,”
Aerosp. Med. Hum. Perform.
,
89
(
6
), pp.
510
519
.10.3357/AMHP.4989.2018
10.
Amer
,
K. B.
, and
Neff
,
J. R.
,
1974
, “
Vertical-Plane Pendulum Absorbers for Minimizing Helicopter Vibratory Loads
,”
J. Am. Helicopter Soc.
,
19
(
4
), pp.
44
48
.10.4050/JAHS.19.44
11.
Braun
,
D.
,
1984
, “
Ground and Flight Tests of a Passive Rotor Isolation System for Helicopter Vibration Reduction
,”
Vertica
,
8
(
1
), pp.
1
14
.https://dspace-erf.nlr.nl/xmlui/bitstream/handle/20.500.11881/1640/ERF-1982-3-8.pdf?sequence=1
12.
Shaw
,
J.
,
Albion
,
N.
,
Hanker
,
E. J.
, and
Teal
,
R. S.
,
1989
, “
Higher Harmonic Control: Wind Tunnel Demonstration of Fully Effective Vibratory Hub Force Suppression
,”
J. Am. Helicopter Soc.
,
34
(
1
), pp.
14
25
.10.4050/JAHS.34.14
13.
Nguyen
,
K.
, and
Chopra
,
I.
,
1992
, “
Effects of Higher Harmonic Control on Rotor Performance and Control Loads
,”
J. Aircr.
,
29
(
3
), pp.
336
342
.10.2514/3.46166
14.
Kube
,
R.
,
Van Der Wall
,
B.
,
Schultz
,
K.-J.
, and
Splettstoesser
,
W.
,
1999
, “
IBC Effects on Bvi Noise and Vibrations-A Combined Numerical and Experimental Investigation
,”
Annual Forum Proceedings-American Helicopter Society
, Vol.
55
, Montreal, QC, Canada, pp.
2282
2291
. https://vtol.org/store/product/ibc-effects-on-bvi-noise-and-vibrations-a-combined-numerical-and-experimental-investigation-5082.cfm
15.
Straub
,
F. K.
,
Kennedy
,
D. K.
,
Stemple
,
A. D.
,
Anand
,
V.
, and
Birchette
,
T. S.
,
2004
, “
Development and Whirl Tower Test of the Smart Active Flap Rotor
,”
Smart Structures and Materials 2004: Industrial and Commercial Applications of Smart Structures Technolgies
, International Society for Optics and Photonics, Vol.
5388
, San Diego, CA, pp.
202
213
..https://www.researchgate.net/profile/Friedrich_Straub/publication/252834340_Development_and_whirl_tower_test_of_the_SMART_active_flap_rotor/links/541af1540cf25ebee988d4ad/Development-and-whirl-tower-test-of-the-SMART-active-flap-rotor.pdf
16.
Wickramasinghe
,
V. K.
, and
Hagood
,
N. W.
,
2004
, “
Material Characterization of Active Fiber Composites for Integral Twist-Actuated Rotor Blade Application
,”
Smart Mater. Struct.
,
13
(
5
), pp.
1155
1165
.10.1088/0964-1726/13/5/020
17.
Wilkie
,
W. K.
,
Wilbur
,
M. L.
,
Mirick
,
P. H.
,
Cesnik
,
C. E.
, and
Shin
,
S.
,
1999
, “
Aeroelastic Analysis of the Nasa/Army/Mit Active Twist Rotor
,”
Annual Forum Proceedings-American Helicopter Society
, Vol.
55
, Montreal, QC, Canada, pp.
545
557
.https://www.researchgate.net/publication/243767804_Aeroelastic_analysis_of_the_NASAArmyMIT_active_twist_rotor
18.
Shen
,
J.
,
Yang
,
M.
, and
Chopra
,
I.
,
2006
, “
Swashplateless Helicopter Rotor System With Trailing-Edge Flaps for Flight and Vibration Controls
,”
J. Aircr.
,
43
(
2
), pp.
346
352
.10.2514/1.14634
19.
Viswamurthy
,
S.
, and
Ganguli
,
R.
,
2008
, “
Using the Complete Authority of Multiple Active Trailing-Edge Flaps for Helicopter Vibration Control
,”
J. Vib. Control
,
14
(
8
), pp.
1175
1199
.10.1177/1077546307081323
20.
Chia
,
M. H.
,
Padthe
,
A. K.
,
Duraisamy
,
K.
, and
Friedmann
,
P. P.
,
2017
, “
An Efficient Approach for the Simulation and On-Blade Control of Helicopter Noise and the Impact on Vibration
,”
J. Am. Helicopter Soc.
,
62
(
4
), pp.
1
15
.10.4050/JAHS.62.042004
21.
Chiu
,
T.
, and
Friedmann
,
P.
,
1997
, “
An Analytical Model for ACSR Approach to Vibration Reduction in a Helicopter Rotor-Flexible Fuselage System
,”
Aeronaut. J.
,
101
(
1009
), pp.
399
408
.10.1017/S0001924000065945
22.
Staple
,
A.
,
1989
, “
An Evaluation of Active Control of Structural Response as a Means of Reducing Helicopter Vibration
,”
Proceedings of the 15th European Rotorcraft Forum
, Amsterdam, The Netherlands, Sept. 12–15, p.
51
.
23.
Welsh
,
W.
,
Fredrickson
,
C.
,
Rauch
,
C.
, and
Lyndon
,
I.
,
1995
, “
Flight Test of an Active Vibration Control System on the UH-60 Black Hawk Helicopter
,”
AHS, 51st Annual Forum
, Fort Worth, TX, May 9–11, pp.
393
400
. https://vtol.org/store/product/flight-test-of-an-active-vibration-control-sytem-on-the-uh60-black-hawk-helicopter-407.cfm
24.
Hackett
,
N.
,
1995
, “
EH 101 Active Control of Structural Response Development, Productionisation and Certification
,” EH 101 Avionics- Civil and Military Conference, London, UK, pp. 5.1–5.10.
25.
Goodman
,
R. K.
, and
Millott
,
T. A.
,
2000
, “
Design, Development, and Flight Testing of the Active Vibration Control System for the Sikorsky s-92
,”
56th Annual Forum, AHS International
, Virginia Beach, VA, May 2–4, pp.
764
771
.https://vtol.org/store/product/design-development-and-flight-testing-of-the-active-vibration-control-system-for-the-sikorsky-s92-4799.cfm
26.
Crocker
,
M. J.
,
2007
,
Handbook of Noise and Vibration Control
,
Wiley
, Hoboken, NJ.
27.
Hiemenz
,
G. J.
,
2007
, “
Semi-Active Magnetorheological Seat Suspensions for Enhanced Crashworthiness and Vibration Isolation of Rotorcraft Seats
,”
Ph.D. thesis
, Department of Aerospace Engineering, University of Maryland, College Park, MD. https://www.semanticscholar.org/paper/Semi-active-magnetorheological-seat-suspensions-for-Hiemenz/ba88a729874e7d4179d460b6d78eefbd9a4e4726
28.
Hiemenz
,
G. J.
,
Hu
,
W.
, and
Wereley
,
N. M.
,
2008
, “
Semi-Active Magnetorheological Helicopter Crew Seat Suspension for Vibration Isolation
,”
J. Aircr.
,
45
(
3
), pp.
945
953
.10.2514/1.32736
29.
Chen
,
Y.
,
Wickramasinghe
,
V.
, and
Zimcik
,
D.
,
2009
, “
Development of Adaptive Seat Mounts for Helicopter Aircrew Body Vibration Reduction
,”
J. Vib. Control
,
15
(
12
), pp.
1809
1825
.10.1177/1077546309103275
30.
Chen
,
Y.
,
Wickramasinghe
,
V.
, and
Zimcik
,
D. G.
,
2011
, “
Development of Adaptive Helicopter Seat for Aircrew Vibration Reduction
,”
J. Intell. Mater. Syst. Struct.
,
22
(
5
), pp.
489
502
.10.1177/1045389X11400343
31.
Paddan
,
G.
, and
Griffin
,
M.
,
2002
, “
Evaluation of Whole-Body Vibration in Vehicles
,”
J. Sound Vib.
,
253
(
1
), pp.
195
213
.10.1006/jsvi.2001.4256
32.
Le
,
T. D.
, and
Ahn
,
K. K.
,
2011
, “
A Vibration Isolation System in Low Frequency Excitation Region Using Negative Stiffness Structure for Vehicle Seat
,”
J. Sound Vib.
,
330
(
26
), pp.
6311
6335
.10.1016/j.jsv.2011.07.039
33.
Maciejewski
,
I.
,
Meyer
,
L.
, and
Krzyzynski
,
T.
,
2009
, “
Modelling and Multi-Criteria Optimisation of Passive Seat Suspension Vibro-Isolating Properties
,”
J. Sound Vib.
,
324
(
3–5
), pp.
520
538
.10.1016/j.jsv.2009.02.021
34.
Virgin
,
L.
,
Santillan
,
S.
, and
Plaut
,
R.
,
2008
, “
Vibration Isolation Using Extreme Geometric Nonlinearity
,”
J. Sound Vib.
,
315
(
3
), pp.
721
731
.10.1016/j.jsv.2007.12.025
35.
Holtz
,
M. W.
, and
Van Niekerk
,
J. L.
,
2010
, “
Modelling and Design of a Novel Air-Spring for a Suspension Seat
,”
J. Sound Vib.
,
329
(
21
), pp.
4354
4366
.10.1016/j.jsv.2010.04.017
36.
Wu
,
X.
, and
Griffin
,
M.
,
1997
, “
A Semi-Active Control Policy to Reduce the Occurrence and Severity of End-Stop Impacts in a Suspension Seat With an Electrorheological Fluid Damper
,”
J. Sound Vib.
,
203
(
5
), pp.
781
793
.10.1006/jsvi.1996.0901
37.
Choi
,
S.-B.
, and
Han
,
Y.-M.
,
2007
, “
Vibration Control of Electrorheological Seat Suspension With Human-Body Model Using Sliding Mode Control
,”
J. Sound Vib.
,
303
(
1–2
), pp.
391
404
.10.1016/j.jsv.2007.01.027
38.
Sun
,
S.
,
Yang
,
J.
,
Deng
,
H.
,
Du
,
H.
,
Li
,
W.
,
Alici
,
G.
, and
Nakano
,
M.
,
2015
, “
Horizontal Vibration Reduction of a Seat Suspension Using Negative Changing Stiffness Magnetorheological Elastomer Isolators
,”
Int. J. Veh. Des.
,
68
(
1/2/3
), pp.
104
118
.10.1504/IJVD.2015.071076
39.
Gan
,
Z.
,
Hillis
,
A. J.
, and
Darling
,
J.
,
2015
, “
Adaptive Control of an Active Seat for Occupant Vibration Reduction
,”
J. Sound Vib.
,
349
, pp.
39
55
.10.1016/j.jsv.2015.03.050
40.
Danh
,
L. T.
, and
Ahn
,
K. K.
,
2014
, “
Active Pneumatic Vibration Isolation System Using Negative Stiffness Structures for a Vehicle Seat
,”
J. Sound Vib.
,
333
(
5
), pp.
1245
1268
.10.1016/j.jsv.2013.10.027
41.
Ning
,
D.
,
Sun
,
S.
,
Zhang
,
J.
,
Du
,
H.
,
Li
,
W.
, and
Wang
,
X.
,
2016
, “
An Active Seat Suspension Design for Vibration Control of Heavy-Duty Vehicles
,”
J. Low Freq. Noise, Vib. Active Control
,
35
(
4
), pp.
264
278
.10.1177/0263092316676389
42.
Fereidooni
,
A.
,
Wickramasinghe
,
V.
, and
Chen
,
Y. E.
,
2018
, “
Compact Vibration Reducing Human Support
,” German Patent and Trade Mark Office/Intellectual Property Office, Munich, Germany/South Wales, Newport, UK, Publication Nos. DE102017128067 and GB2559035.
43.
Scribner
,
K. B.
,
Sievers
,
L. A.
, and
von Flotow
,
A. H.
,
1993
, “
Active Narrow-Band Vibration Isolation of Machinery Noise From Resonant Substructures
,”
J. Sound Vib.
,
167
(
1
), pp.
17
40
.10.1006/jsvi.1993.1319
44.
Jenkins
,
M.
,
Nelson
,
P.
,
Pinnington
,
R.
, and
Elliott
,
S.
,
1993
, “
Active Isolation of Periodic Machinery Vibrations
,”
J. Sound Vib.
,
166
(
1
), pp.
117
140
.10.1006/jsvi.1993.1287
45.
Hansen
,
C.
,
Snyder
,
S.
,
Qiu
,
X.
,
Brooks
,
L.
, and
Moreau
,
D.
,
2012
,
Active Control of Noise and Vibration
,
CRC Press
, Boca Raton, FL.
46.
Siebert
,
W. M.
,
1986
,
Circuits, Signals, and Systems
, Vol.
2
,
MIT Press
, Cambridge, MA.
47.
Fereidooni
,
A.
,
Graham
,
S.
,
Chen
,
E.
, and
Wickramasinghe
,
V. K.
,
2017
, “
Investigation of a Parallel Active Vibration Isolation Mount for Mitigating N/Rev Helicopter Vibrations
,”
AIAA
Paper No. 2017-1441. 10.2514/6.2017-1441
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