The Lightcraft Project

Nette BrocksColumbia High School

Introduction

“The industry concerned with the design and manufacture of aircraft, rockets, missiles,

spacecraft, etc.”

IntroductionA rocket is “any device propelled

by the ejection of matter”Challenge= finding the cheapest

and most efficient fuel that can be ejected

Chemical fuelsAlready operate at efficiencies so

high that progress may be physically unattainable

IntroductionBeamed Energy Propulsion (BEP)

for an “era beyond oil”Electromagnetic energy is beamed

from a remote source to a craft for direct conversion into thrust

The majority of system mass is left on the ground

Introduction

Introduction

Introduction

Introduction

30 km

Review of Literature Dumas, Larry N., and Amy L. Walton.

"Faster, Better, Cheaper: An Industrial View." Acta Astronautica Vol. 47 (2000): 607-621. Print.Discussed the “new approach featuring

focused, technically sophisticated, fast track missions.”

Davis, Eric W., and Franklin B. Mead. "Review of Laser Lightcraft Propulsion System (Preprint)." (2007). Print.Explained the motives, configuration, benefits,

life-cycle cost, estimated future costs, and Demonstration Program behind the Lightcraft

Review of Literature“Ground and Flight Tests of a Laser

Propelled Vehicle,” Elucidated the experiments of the new

technology“Flight Experiments and Evolutionary

Development of a Laser Propelled, Trans-atmospheric Vehicle” Summarized the background, technology

design, and testing results of the concept.

Review of LiteratureSalvador, Israel I., and Leik N. Myrabo.

"Airbreathing Hypersonic Laser Thermal Propulsion Experiments with a Lightcraft Vehicle- Status Update." PrintSuggested that the formation of blast waves was

dependent of ignition surfaceKenoyer, David A., Israel Salvador, Leik N.

Myrabo, Samuel N. Notaro, and P. W. Pragulla. "Experimental Investigation of Axial and Beam-Riding Propulsive Physics with TEA CO2 Laser." Print.Tested lateral impulses

Hypothesis

Methods and Materials: Schlieren

Two Lumonics K-922M CO2 TEA lasers were fired

Laser 1 has 17 Jewels per shot; Laser 2 has 13 Jewels per shot

The beams reflected off a series of mirrors and hit a flat plate in unison

The flat plate set at 45º, 25º, and 0º angles to mimic different Lightcraft geometries

Methods and Materials- Schlieren

Various plate angles to determine if blast wave characteristics are independent of ignition surface

Methods and Materials: AIMDAngular Impulse Measuring Device

Lateral impulsesThe Lightcraft was attached to the AIMD in an

extended and a retracted position

The center of the Lightcraft was offset in increments of 5 mm The offsets represented a range of -10% to

+55% of the engine diameter

Methods and Materials-AIMD

Laser 1 fired

An oscilloscope, attached to the AIMD, recorded the motion of the test engine

Methods and Materials: AIMD

Calculations: AIMDEquations derived using the Equations of

Motion

rc2= distance from spin axis to impulse (extended)=.1135 m

rc1= distance from spin axis to impulse (retracted)=.0786 m

IR= moment of inertia of the motorω=Angular velocity at moment after impulse;

in radians per second

12

))(())(( )()(

cc

retractedRextendedR

rrIIimpulse retractedextended

Calculations: AIMDIR= moment of inertia of the motor

Extended= 2.336E-4 Nms2

Retracted= 9.804E-5 Nms2

used the equationK=spring constant=155.1N/mr= spring distance from the spin axis

= .04604 mT=period (s)

Extended=0.1675Retracted=0.1085

2

22

)2( TKrIR

Calculations: AIMDω=Angular velocity at moment after

impulse; in radians per secondThe oscilloscope measured volts and

secondsData was transferred from the

oscilloscope to an excel chartBy taking the slope (volts/seconds) of

the output voltage vs. time plot and converting using a known calibration (0.1367 volts = 1 radian), angular velocity in radians/second was calculated

QuickTime™ and a decompressor

are needed to see this picture.

Calculations: AIMDSince the angular velocity and the

resulting slope changed rapidly with time, the range over which the slope was determined was reduced to a small range immediately after the laser pulse (E325:E425, D325:D425)

At the -10mm offset this domain yielded error; in this case the slope function was restricted to (E340:E425, D340:D425)

Calculations: AIMDOnce impulse was calculated using

this information, it was multiplied by a factor of 1000000/17 to produce the momentum coupling coefficient

The momentum coupling coefficient is equal to force thrust divided by beam power

Results: AIMD

-150

-100

-50

0

50

100

150

-40 -20 0 20 40 60

Cm (N

/MW

)

Offset in Millimeters

Graph 1: Cm(N/MW) v. Offset in Millimeters

Original #200-2/3 w/Delrin (Brocks)#200-2/3 Delrin (Kenoyer)

#200-2/3 Airbreathing(Kenoyer)#200-2/3 w/Delrin(Brocks)

Results: AIMD

-150

-100

-50

0

50

100

150

-40 -20 0 20 40 60

CM (N

/MW

)

Offset in Millimeters

Graph 2: CM (N/MW) v. Offset in Millimeters

Original #200-2/3 w/Delrin (Brocks)

#200-2/3 Delrin(Kenoyer)

#200-2/3 Airbreathing(Kenoyer)

#200-2/3 w/Delrin(Brocks)

Discussion

QuickTime™ and a decompressor

are needed to see this picture. QuickTime™ and a decompressor

are needed to see this picture.

ConclusionBoth hypothesizes were supported

The inside of the shroud was lined with Delrin, and 00.028 grams were ablated during AIMD testingChipping of the propellant caused irregular

results

Thanks toDr. David KenoyerDr. Israel SalvadorDr. Leik MyraboMs. Heidi GleasonMs. StraussOlder and current Science

Research studentsFriends and family

Bibliography  “Aerospace.” Dictionary.com. Website.  Aldrin, Buzz, and David Nolan. "A Bolder Mission." August 2009. Popular Mechanics. Print.   Chaikin, Andrew. “For Neil Armstrong, the First Moon Walker, It Was All About Landing the

Eagle.” Davis, Eric W., and Franklin B. Mead. "Review of Laser Lightcraft Propulsion System

(Preprint)." (2007). Print. Discovery Channel. NASA in Your Home. Discovery Channel. Website. 12 Dec. 2009.

http://www.dsc.discovery.com/tu/nasa/home-and-city/home-and-city-html.  Dumas, Larry N., and Amy L. Walton. "Faster, Better, Cheaper: An Industrial View." Acta Astronautica Vol. 47 (2000): 607-621. Print.  Edwards, Owen. “One Giant Leap.” Smithosian. Website. Goldwasser, Samuel M. "Sam's Laser FAQ - Laser Safety." Sci.Electronics.Repair FAQ: Home

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HowStuffWorks. Website. 12 Dec. 2009. http://www.science.howstuffworks.com/nasa-inventions.htm.

Kenoyer, David A. "Combined Experimental and Numerical Investigations into Laser Propulsion Engineering Physics." Diss. Rensselaer Polytechnic Institute, 2010. Print.

Kenoyer, David A., Israel Salvador, Leik N. Myrabo, Samuel N. Notaro, and P. W. Pragulla. "Experimental Investigation of Axial and Beam-Riding Propulsive Physics with TEA CO2 Laser." Print.

Kenoyer, David A. Personal interview. 23 July 2010.  "Laser-powered Jet Engine." Halfbakery. 14 Mar. 2008. Website. 28 Dec. 2010.

http://www.halfbakery.com/idea/Laser-powered_20Jet_20Engine.

Bibliography Lightcraft: A Laser Push to Orbit. Centauri Dreams. 14 Sep. 2009. Website. 14. Jan. 2010.

http://images.google.com/imgres?imgurl=http://www.centauri-dreams.org/wp-content/uploads/2009/09/lightcraft1.jpg&imgrefurl=http://www.centauri-dreams.org/%3Fp%3D9413&usg=__ZzH_L4UmMDSsCajgmC2vR7zpYHw=&h=342&w=500&sz=30&hl=en&start=10&tbnid=vGhTa_lLOEQvDM:&tbnh=89&tbnw=130&prev=/images%3Fq%3DLightcraft%26gbv%3D2%26hl%3Den%26safe%3Dactive

 Lord, Morgan. “NASA’s New Modular Spacesuit Wil Handle Any Mission.” Popular Mechanics August 2009. Website.

Mead, Franklin B., and Leik N. Myrabo "Flight Experiments and Evolutionary Development of a Laser Propelled, Trans-atmospheric Vehicle." (1998). Print.

 Mirror.co.uk.Website. 12 Dec. 2009. http://www.mirror.co.uk/news/topstories/2009/07/21.  Oberg, James. “How we'll return to the Moon.” Astronomy August 2009: 37(8), 24-29.

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1978. Print. Salvador, Israel I., and Leik N. Myrabo. "Airbreathing Hypersonic Laser Thermal Propulsion Experiments

with a Lightcraft Vehicle- Status Update." Print Salvador, Israel I. "Static and Hypersonic Experimental Analysis of Impulse Generation in Air-

Breathing Laser-Thermal Propulsion." Diss. Rensselaer Polytechnic Institute, 2010. Print.  Siuru, Bill. "Laser to Lift Lightcraft Into Space." Mechanical Engineering. Sept. 1990. 54-57.

Print.  Simpson, Bruce. My Jet Engine Projects. 12 Apr. 2009. Website. 12 Dec. 2009.

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Any questions?