Vibrational Gyroscopes in Instrumentation and in Creation Robert - PowerPoint PPT Presentation

Vibrational Gyroscopes in Instrumentation and in Creation Robert Leland Oral Roberts University rleland@oru.edu L: flickr.com R: en.wikipedia.org/wiki/Halteres

Good design is a reflection of a wise designer.

Even in the insects that God has created, we see complex, effective engineering design. Vibrational gyroscopes are examples of this. They are found in both flies and man-made motion control systems. Vibrational gyroscopes illustrate important aspects of design in creation: 1. Similar structures and functions in biological and electro-mechanical systems 2. Successful integration into a larger, complex system. 3. A detailed process for fabrication/development. Wikipedia Commons www.nasa.gov/centers/dryden/multimedia/imagegallery/F-16AFTI/EC89-0016-20.html

A vibrational gyroscope uses a vibrating structure to measure rotation rate. There are no spinning parts. They measure their own rotation rate without reference to anything outside the body (inertial measurement). Used in attitude control (orientation) and navigation of Cassini Spacecraft aircraft and spacecraft. www.jpl.nasa.gov Gyroscopes are also found in iPhones, Wii controllers and flies.

A vibrational gyroscope can be modeled as a mass supported by springs. The mass is driven to Spring K vibrate along the drive axis Mass M When the gyroscope Sense rotates about an axis Axis coming out of the Drive Axis screen, a Coriolis force creates a vibration along the sense axis. Rotation rate is determined from the sense axis vibration.

An actual Micro Electro Mechanical System (MEMS) Gyroscope might look like this: Combed fingers for driving and sensing motion. Photo available as Figure 6 at This gyro has two www.sensorsmag.com/sensors/acceleration-vibration/an- vibrating masses, overview-mems-inertial-sensing-technology-970 like a tuning fork. Draper Tuning Fork Gyroscope Acceleration/Vibration An Overview of MEMS Inertial Sensing Technology February 1, 2003 By: Jonathan Bernstein, Corning- IntelliSense Corp. Sensors Online

Insects in the order Diptera have vibrational gyroscopes. Diptera = 2 wings (instead of 4) Includes Drosophila (fruit flies) Rear wings are replaced with ‘posts’ called halteres. The halteres vibrate and function as gyroscopes. Crane Fly Commons.wikimedia.org

The first Jet Propulsion Laboratory (JPL) microgyro used a rocking post similar to a fly haltere. Rocks in one direction along the drive axis. The other direction is the sense axis Aerospace Technology EEE Links Vol. 6 No. 1 Mar 2000 NASA Electronics Parts Innovation Nov/Dec 1999 and Packaging Program

A similar gyroscope we developed at the University of Alabama uses a rocking post with strain sensors S. Kotru, R. K. Pandy, P. Periaswami, A. Highsmith Finite Element Analysis John Jackson Sensors are formed by depositing and patterning a piezoelectric material (PNZT) on a silicon wafer These sensors measure strain, (the fraction a surface is stretched or compressed). Strain provides a measurement of the bending of the supports, hence measuring the rocking of the post

In a similar manner, fly halteres vibrate and their motion is sensed. Haltere motion is sensed by five sensor fields called campaniform sensilla which sense strain like the University of Alabama gyro Most of these fields measure the back and forth motion of the halteres (drive axis) One field measures motion at a CSIRO ScienceImage 3237 Fly haltere.jpg Wikipedia Commons right angle to this vibration (sense axis) This last field sends signals directly to the motor neurons of the fly’s turning muscles M. H. Dickenson Integr. Comp. Biol., 45:274 – 281 (2005) A. Fayyazuddin, M. H. Dickinson, J. of Neuroscience, August 15, 1996, 16(16):5225 – 5232

God’s design in nature achieves specific survival goals

Halteres are used in attitude control and allow the insect to have a shorter body, which is more maneuverable. “The critical role of the haltere in flight stability was first identified in 1714 by William Derham, who showed that a fly could not remain airborne if its tiny halteres were surgically removed. . .” Quote from: M.H. Dickinson, Integr. Comp. Biol., 45:274 – 281 (2005) Halteres identified as gyroscopes in 1938 G. Fraenkel, J. W. S. Pringle, Nature 141:919 – 920. (1938) Show stable and unstable aircraft

The halteres are critical in performing rapid direction changes in Drosophila (fruit flies) Flies make rapid 90 o turns in midair. These turns take about 1/20 of a second. In order to control these turns, flies sense rotation visually and with their halteres. Possible trajectory The halteres appear to respond more quickly than the vision system. b1 muscle vision system Experiments suggest: haltere Visual sensing is used to initiate the turn. The halteres are used in ending the turn by making a quick counter-torque. commons.wikimedia.org M. H. Dickenson Integr. Comp. Biol., 45:274 – 281 (2005 )

God’s design in nature involves complex, interconnected systems Complexity ≠ Good engineering design Successful, efficient, and reliable performance of tasks requiring complexity = Good engineering design

Successful flight requires flight control. The Wright brothers achieved controlled, powered flight Controlled by Wilbur and Orville using wing warping. The body of the aircraft is extended, which increases stability.

The AFTI F16 uses a much more complex digital flight control system that coordinates a large number of control surfaces. It can move left or right, and up or down without turning, banking, or pitching up or down. www.nasa.gov/centers/dryden/multimedia/imagegallery/F-16AFTI/EC89-0016-20.html General Dynamics F-16A AFTI 1.50- 2.07 https://www.youtube.com/watch?v=iClN05EWuEY

Flies are capable of incredibly complex maneuvers using their wings and a wide array of sensors. The fly is capable of making complex responses to predators. The fly must determine the presence and position of a predator, estimate the time to respond, and initiate a complex flight sequence involving large changes in both orientation and direction. G. Bohne, wikimedia commons This all happens literally in the blink of an eye, and requires coordination of sensors, brain function and muscles. http://tedxcaltech.com/content/michael-dickinson 1.25-1.44

Insect flight is more complex than aircraft flight. Forward Stroke Wikipedia Commons Backward Stroke Insect wings sweep back and forth at different angles and create a leading edge vortex (air rotation) above the wing that produces upward lift forces Most aircraft wings are airfoils that use streamlined airflow to create a lower pressure above the wing producing lift. en.wikipedia.org

Flies use two sets of muscles to fly. www.flickr.com Power muscles move the wings back and forth without direct control of beating from the brain (design efficiency) Steering muscles contract quickly to alter the hinge joints of the wings to create turns

Flies use a large number of sensors in flight control. commons.wikimedia.org en.wikipedia.org Wing sensors: can sense changes in shape of the wing Antenna: Can sense wind Halteres: Sense rotation Eyes: Fastest visual system on earth Brain: About 100,000 neurons Ocelli: Eyes, function unknown (design efficiency)

Insect flight requires a number of complex systems working together properly. “When considering the control of complex aerial behaviors, it is impossible to disentangle the aerodynamics of flapping from the mechanics of the wing hinge, the physiology of the flight muscles, or the properties of sensory-motor circuits in the brain. M. H. Dickinson, Integr. Comp. Biol., 45:274 – 281 (2005 ) www.flickr.com God’s design in nature involves the successful coordination of complex interconnected systems.

God’s design in nature includes development and growth mechanisms Design of a MEMS gyroscope considers both the final product and the process to make it. iPhone 4 Gyroscope www.flickr.com

MEMS designers think in terms of the steps for fabricating a device, not just the final product. en.wikipedia.org Computer Aided Design software is linked to the fabrication process.

Insect Fabrication Process: Metamorphosis Haltere development is controlled by a single gene: Ultrabithorax (Ubx). Without this gene, they develop into wings. Halteres develop from flat imaginal discs in the larva. Disc from leg During metamorphosis, these en.wikipedia.org discs are extended so the center of disk becomes the far end of the haltere. Drosophila imaginal discs en.wikipedia.org

Vibrational gyroscopes in Diptera are a critical part of a complex flight control system designed by God. Insect flight control systems display amazing engineering design. God’s design in nature includes achieving survival goals, integration into a larger system, and the ‘fabrication’ process. Micro Air Vehicle en.wikipedia.com Insect flight control was recognized as displaying God’s wisdom in creation long before creation-evolution debates. Negative stereotypes of people who pull wings off flies should be reconsidered. www.flickr.com