http://apologeticspress.org/APContent.aspx?category=12&article=927
Morphing Flight: Beyond Irreducible Complexity
[EDITOR’S NOTE: A.P. auxillary staff scientist Dr. Fausz holds a Ph.D. in Aerospace Engineering from Georgia Tech.]
Researchers and observers have long recognized that birds and various
other flying creatures change the positioning of their body structures
in flight in order to perform specific maneuvers or adjust their
aerodynamic profile to accommodate changing flight conditions. This
adaptive orientation of body shape has been dubbed “morphing” in the
popular literature. The words “morph” and “morphing” are actually
digressive forms of the word “metamorphosis,” which derives from the
Greek “
meta” (to change) and “
morfe” (form). This is
an apt description of the ability that birds possess to change the form
or geometry of their bodies for increased maneuverability, as well as
for stable flight in a wide variety of ambient conditions.
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This eagle is pulling its feet against its body to
reduce aerodynamic drag. Note also the craning of the wings (normally
used to slow descent speed) and the spreading of the wing feathers to
break up wing tips vortices that increase drag.
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This capability has always been respected and often mimicked by
aircraft engineers to the extent that it has been technologically
possible to do so. Furthermore, bird observations have often inspired
technological advancement in aircraft design and development. The Wright
brothers incorporated morphing into their first successfully powered
aircraft design. In a letter, Wilbur Wright described the biological
observation that was the basis for this morphing design:
My observation of the flight of buzzards leads one to believe that
they regain their lateral stability when partly overturned by a gust of
wind, by a torsion of the tips of the wings (Wright, 1900, Image 4).
Consequently, the Wright brothers designed their first aircraft to be
able to “twist” its wings for lateral stability and control, mimicking
bird capability. Another well-known example of morphing in aircraft
design is retractable landing gear which serves the same purpose for
aircraft as when a bird pulls its feet up to its body in flight. That
is, this type of morphing dramatically decreases aerodynamic drag which,
in turn, increases energy efficiency for the bird of prey—which
translates to fuel efficiency in aircraft. Additional “low-tech”
examples of morphing include movable control surfaces used to impart
forces and torques on the aircraft for maneuvering and stability, wing
“slats,” “slots,” and “flaps” that extend to change the shape of the
wing, providing higher lift at lower speeds for takeoff and landing, and
variable “sweep” wings that allow aircraft to fly efficiently at
dramatically differing flight speeds, such as in transitioning from
subsonic to supersonic flight. In contrast with these examples of “low
tech” morphing designs of the past, a morphing aircraft has been defined
as “one that utilizes innovative actuators, effectors, or mechanisms to
adapt its state
substantially in order to enhance
behavior and performance in addressing multiple environments” (Love, et
al., 2007, emp. added). These past examples of morphing technologies
were certainly innovative in their time, but are now fairly
commonplace—not even considered “morphing” by some.
Nonetheless, research in new innovation for morphing aircraft is once again looking to birds for inspiration and guidance. NASA Administrator Dan Goldin stated:
NASA will open the door to a bold and
revolutionary era by using technology to mimic nature. The seemingly
effortless flight of birds provides the inspiration for new aircraft
utilizing wings that reconfigure in flight. The vehicle changes—or
morphs—from a low-speed configuration to one more suited for high speed
(as quoted in Levine, 2001).
NASA is not the only organization actively pursuing aircraft morphing technology, however. A recent
article described an unmanned aerial vehicle (UAV)
currently under development, called “Roboswift” as “a small,
remote-controlled aircraft that changes shape to mimic the aerodynamic
profile of a swift” (Simonite, 2008). A researcher at the University of
Florida, also studying morphing technology for UAVs, commented:
Despite the past century of innovation in aircraft technology, the versatility of modern aircraft remains far worse than airborne biological counterparts.
The shape changing accomplished by birds and bats in flight stands as
one of the few examples of true morphing. As such, the aircraft
community is devoting considerable attention to the study of biological
systems and how they might be implemented on a flight vehicle
(Abdulrahim, 2005, emp. added).
Clearly, research in aircraft technology and design continues to draw ideas and inspiration from
nature’s flyers. It is also clear that
our technical capabilities seriously lag behind
their natural abilities.
In spite of the fact that aerospace researchers have birds and other
flying creatures to show them “how it’s done,” morphing aircraft design
poses some very daunting technical challenges. This fact was discussed
in an article describing the Morphing Aircraft Structures (MAS) project being carried out by the Lockheed Martin company with funding from the Defense Advanced Research Projects Agency (DARPA):
Morphing technology development requires integrated research in
materials, smart structures, multi-functional airframe, and adaptive
control. It is necessary to evaluate these constitutive technologies in a
morphing vehicle to establish requirements and assure readiness for
technology implementation (Love, et al., 2007).
Another research team, funded by the Air Force Research Laboratory (AFRL)
and Northrup Grumman, further stated: “Significant design challenges
require advances in smart structures and materials (skins), actuation
and power distribution, and feedback control of the morphing structure”
(Ghandi, et al., 2007). The implication here is that morphing design is
highly multi-disciplinary (structures, aerodynamics, control, etc.) and
that all of these areas require additional research before the
technology readiness level will be sufficient to actually build a true
morphing aircraft. These examples only scratch the surface of the
extreme levels of government funding and human resources that have gone
into morphing aircraft research, yet there is still much work that must
be done before a viable design can be realized, mainly due to the
multi-disciplinary nature of the problem.
Given the substantial resources that have been poured into morphing
aircraft research without yet achieving the final objective, it seems
inconceivable that researchers would look at their biological
inspiration and assume that the capabilities they are striving to
emulate were derived from an unprompted, undirected natural process.
That is, however, what often occurs. Consider what one evolutionist
insisted:
This provides a cautionary note for those pursuing biomimicry, direct
replication of biological features: essential aspects of those
biological features may be driven by secondary characteristics or
functions unrelated to the features’ primary functions. The bat wing,
with all of its elegant modifications for flight, is an obvious example.
It is derived from a typical vertebrate forelimb with all of the
associated musculature, skeletal, and neuronal architectural
characteristics that were originally developed for terrestrial or
aboreal locomotion. That is, it was not designed for propulsive flight a
priori as an engineered device might be, but was modified from other
structures that originated for other functions (Evers, 2007, p. 10).
Dr. Evers issued a warning here to all those engaged in morphing
aircraft research that are proceeding from the perspective of biomimicry
(copying nature)—that they may be in fact designing structures that are
not optimally suited to their purpose because they are copying from
organic structures that, presumably, were not designed for the purpose
they serve. Note, however, that Dr. Evers states that the bat wing was
“modified from other structures
that originated for other functions”
(p. 10, emp. added). One might wonder how the bat wing “was not
designed for propulsive flight a priori,” but the “typical vertebrate
forelimb,” from which it supposedly derived, “originated for other
functions.” This type of “doublespeak” is not uncommon, however, in
Darwinist writings, and it belies an underlying difficulty with
Darwinian thought. Nature’s machines are so good at what they do that it
is difficult for even die-hard Darwinists to accept that they all arose
as a result of an undirected process even while arguing that they did.
Dr. Evers’ comments also illustrate how Darwinists will often focus on
the structural aspects of animal functionality when comparing
characteristics of different animals. As we have already noted here,
however, morphing flight is an example of a capability that involves so
much more than just the structural configurations that give animals such
as bats, birds and butterflies the ability to fly. Indeed, morphing
flight is a highly multi-disciplinary skill. The different disciplinary
facets of morphing may be broken down as follows:
SENSING
Flying creatures and machines must be able to detect or sense the
condition of the atmosphere around them, as well as their own position
and structural configuration, in order to be able to carry out the
activity of flying in a given environment. Examples of the types of data
that must be gathered include air speed, altitude, air pressure,
position relative to other objects, and the position and shape of their
wings at each moment (especially true if morphing is being employed).
This capability can involve highly specialized sensors in aircraft such
as angular rate gyros for measuring orientation, and ports along the
wing for measuring air pressure. Flying animals are able to make use of
typical animal sensing capabilities such as vision, hearing, and smell,
but must also rely on some very special sensor systems. Examples of
these special sensors in animals include echo-location in bats (
Colley,
2004), a bird’s ability to sense linear and angular acceleration with
its ears (Pennycuick, 2008, p. 307), and highly sensitive hair-like
mechanoreceptors that allow insects to sense the approach of potential
predators (Vaidyanathan, et.al., 2001). It has even been suggested, in
recent research, that birds can sense the magnetic field of the Earth,
providing valuable information for navigation (Brahic, 2008).
COMPUTATION
The sensor inputs from eyes, ears, etc., as well as specialized sensor
systems, must be integrated and processed in the brain for biological
flyers, or alternatively, the flight computer if one is considering the
sensor systems of flying machines. The processing that must be carried
out includes specialized algorithms for flight stability, guidance,
navigation, and control. Flight stability is arguably the most important
of these functions, since without stability it is impossible to remain
in flight, and lack of stability in flying can easily lead to tragic
results. In aircraft, flight stability algorithms are executed at the
highest possible processing speeds and given top priority for processor
usage. Guidance is the function that determines, to the highest possible
accuracy, where the flyer is currently located, particularly with
respect to where it needs to go. On the other hand, navigation compares
guidance information with known geographical waypoints to compute the
“best” course for the flyer to follow to end up where the guidance
function wants it to go. The control function takes guidance and
navigation information and generates commands for the actuation system
to steer the flyer along the computed course. In biological flyers,
these commands are electrical impulses from the brain that stimulate
specific muscles and organs. In aircraft, the commands are also
electrical signals that activate electric motors or trigger hydraulic
actuation. Given the computational requirements of flight locomotion, it
may not be surprising that the size of a bird’s brain with respect to
its body size is, on average, 10 times that of the reptiles with whom
they are assumed to share common ancestry (Jerison, 2004).
ACTUATION
Morphing flight requires highly specialized structures, but it also
requires equally specialized actuators to move and position those
structures. The very definition of morphing aircraft, given previously,
describes an aircraft that “utilizes innovative actuators, effectors, or
mechanisms” (Love, et al., 2004). Natural flyers, as well, require a
specialized skeletal structure and attached musculature to perform their
amazing feats of aerial acrobatics. Mujahid Abdulrahim discussed the
wing craning actuator on his morphing aircraft design and the
specialized bird structure that it was modeled after:
The wing craning (gull-wing) mechanism is loosely modeled after a set
of parallel bones connecting the shoulder and elbow joints of a bird
wing. A rotation of the shoulder joint in the vertical plane results in
an extension or contraction of the entire wing. The skeletal mechanism
provides a geometric ratio between the extension of the inner and outer
bones. Such a mechanism allows the bird to morph into a variety of
positions using a single movement. Each of the positions is largely
stable and affords a unique capability within the flight envelope
(2005).
The specialization of this “skeletal mechanism” for morphing flight is
clearly illustrated in this narrative, and the muscles that actuate
these motions would be expected also to be specialized for the task in
their attachments to the skeletal structure, as well as their
configuration.
So, each of these “subsystems” require specialized components to
fulfill their part in enabling the wonders of morphing flight. The
manner in which these subsystems interact, however, is equally critical
to the success of morphing in providing a positive contribution to
flight capability. The sensory outputs have to provide specific
information to be useful for stability, guidance and navigation, and the
computational capability has to have sufficient processing capacity and
be “wired” in such a way as to operate effectively on that information.
Similarly, the computation function has to possess information about
actuator configuration and dynamics in order to output appropriate
command signals to achieve the objective of flight stability and to
successfully execute the desired motion in flight. Finally, the
actuators have to possess the dynamic range, as well as force and torque
magnitudes, to achieve the necessary changes in body shape and position
in a timely fashion.
Multiple components of bird anatomy have been studied in the literature
with respect to the irreducible complexity they possess regarding the
bird’s ability to fly. For example, Matthew Vanhorn discussed the
amazing complexity of bird feathers (
Vanhorn,
2004), Caleb Colley pointed out how bats use their ears (hearing) for
echolocation (2004), and irreducible complexity has been examined in
general terms with regard to various components of bird physiology (
Fausz,
2008). These discussions of the various elements of bird physiology are
compelling irreducible complexity arguments when one considers the
specialized requirements of flight systems (cf.
Miller, 2006, 5[2]:5-R).
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This block diagram illustrates the interconnection
and interdependence of the major subsystems involved in achieving
advanced flight capability.
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When these physical components are considered in a system context,
however, the arguments of irreducible complexity are taken to a whole
new level. As discussed, the bird’s brain must have sufficient capacity
to carry out the required computations, but this capacity is useless for
flight without the required sensor information or the appropriate
actuation systems for carrying out the computed commands. Likewise,
without the necessary brain capacity the specialized sensing and
actuation components would serve no purpose, and would likely be
detrimental to survival. Useful flight capability is not possible
without flight stability, at a minimum, and this is only possible if the
necessary sensor, computer,
and actuator components are
all in place. Indeed, attempting flight without stability will, with high probability, result in the death of the flyer.
The multi-disciplinary nature of morphing flight has already been discussed, but is further reflected in the following:
To lay the foundation for a truly multi-role aircraft,
multidisciplinary research efforts are currently focusing on
technologies that enable substantial changes to the wing
configuration.... Aerodynamics analysis [sic] (including unsteady and
transient aerodynamics) are also important to accurately characterize
the vehicle for control surface sizing, engine compatibility, and
flight-control design. Despite significant strides to develop wing
structure and actuation systems, much work remains to effectively
control both the morphing planform as well as the entire morphing
aircraft (Ghandi, et al., 2007).
This discussion illustrates that, even in focused research, it is
difficult to make sure that all aspects of a significant
multi-disciplinary problem are given adequate attention. This is no less
true when it comes to biological creatures capable of morphing flight.
The irreducible complexity associated with bird feathers and other
components of bird physiology are enough of a challenge to the Darwinian
notion of natural selection to render it
impractical.
However, when one considers the system level implications of morphing
flight, and the necessity of simultaneous development of multiple
combinations of these physical components, natural selection as an
explanation for morphing flight capability is seen to be
absolutely irrational.
Furthermore, the difficulty of achieving this capability in flying
machines, even with substantial resources focused within a significant
research effort, illustrates that birds are the product of, not just
design, but of an incredibly capable Designer with an unparalleled
understanding of the multi-disciplinary nature of the problem. That
Designer, of course, is God, who spoke to Job on this subject:
Does the hawk fly by your wisdom,
and spread its wings toward the south?
Does the eagle mount up at your
command, and make its nest on high?
On the rocks it dwells and resides,
on the crag of the rock and the stronghold.
From there it spies out the prey; its
eyes observe from afar (Job 39:26-29).
Here God describes the computational capability inherent in a hawk
flying by “wisdom” and an eagle by “command.” He also indicates the
tremendous acuity of the eagle’s eyes for sensing prey, as well as
several other facts about the behavior of these birds. Truly, only an
omniscient, omnipotent God would possess this knowledge
and
the ability to apply it in such wondrous works of design and creation.
Few birds have more impressive morphing flight capability than birds of
prey, such as hawks and eagles, making them perfect examples of the
amazing design ability of the Creator.
REFERENCES
Abdulrahim, Mujahid (2005), “Flight Performance Characteristics of a Biologically-Inspired Morphing Aircraft,” 43rd AIAA Aerospace Sciences Meeting and Exhibit, January 10-13, Reno, NV.
Brahic, Catherine (2008), “Birds Can ‘See’ the Earth’s Magnetic Field,”
New Scientist, [On-line], URL: http://www.newscientist.com/article/dn13811-birds-can-see-the-earths-magnetic-field.html.
Colley, Caleb (2004), “Bat ‘Vision’,” Apologetics Press, [On-line], URL:
http://www.apologeticspress.org/articles/2633.
Evers, J.H. (2007), “Biological Inspiration for Agile Autonomous Air Vehicles,”
Platform Innovations and System Integration for Unmanned Air, Land and Sea Vehicles (AVT-SCI Joint Symposium). Meeting Proceedings RTO-MP-AVT-146, Paper 15: 1-14. Neuilly-sur-Seine, France: RTO, [On-line], URL: http://www.rto.nato.int/abstracts.asp.
Fausz, Jerry (2008), “Designed to Fly,”
Reason and Revelation, 28[2]:9-15, February, [On-line], URL:
http://www.apologeticspress.org/articles/3599.
Ghandi, N., Jha, A., Monaco, J., Seigler, T.M., Ward, D. and Inman,
D.J. (2007), “Intelligent Control of a Morphing Aircraft,” 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, April 23-26, Honolulu, Hawaii.
Jerison, Harry J. (2004), “Dinosaur Brains,”
Encyclopedia of Neuroscience (CDROM: Elsevier), third edition.
Levine, Jay (2001), “The Morphing Aircraft,”
The Dryden X-Press, NASA Dryden Flight Research Center, [On-line], URL: http://www.dfrc.nasa.gov/Newsroom/X-Press/stories/043001/new_morph.html.
Love, M.H., Zink, P.S., Stroud, R.L., Bye, D.R., Rizk, S. and White, D.
(2007), “Demonstration of Morphing Technology through Ground and Wind
Tunnel Tests,” 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, April 23-26, Honolulu, Hawaii.
Miller, Dave (2006), “Bee Flight Physics,”
Reason & Revelation, 5[2]:5-R, February, [On-line], URL:
http://www.apologeticspress.org/articles/2839.
Pennycuick, Colin J. (2008),
Modelling the Flying Bird (San Diego, CA: Academic Press), first edition.
Simonite, Tom (2008), “Morphing Aircraft Mimics a Bird on the Wing,”
New Scientist, March 6, [On-line], URL: http://www.newscientist.com/article/dn13419-morphing-aircraft-mimics-a-bird-on-the-wing.html.
Vaidyanathan, Ravi, Roger D. Quinn, Roy E. Ritzmann, and Troy S. Prince
(2001), “An Insect-Inspired Endgame Targeting Reflex for Autonomous
Munitions,” International Conference on Intelligence Robots and Systems,
October, 2001, Wailea, Hawaii.
Vanhorn, Matthew (2004), “Words of a Feather,” Apologetics Press, [On-line], URL:
http://www.apologeticspress.org/articles/2610.
Wright, Wilbur (1900), “Letter to Octave Chanute,” The Wilbur and
Orville Wright Papers, May 13, Library of Congress, [On-line], URL: http://tinyurl.com/ybropwa.
As
legislators are fighting over the legitimacy of same-sex marriages,
activist judges are claiming constitutional sanction in their redefining
of marriage, and the rank and file citizens of these United States are
embroiled in a polarizing culture war, it is nevertheless unthinkable
that the President of these United States has announced his approval of
homosexuality. If God exists and the Bible is His revealed Word, then
America is facing imminent peril. The evaporation of Christian
principles from American civilization will lead to the extinction of
civility, freedom, and morality.