Infrared Seeker Calibration Mechanism Raytheon Seekers Infrared Seeker Calibration Mechanism Raytheon Seekers

Raytheon Seekers Aaron Scrignar……Team Leader Eric Draves………..Historian Trevor Moody…….Web Page Des., Mediator Stacy Davison……..Document Coord., Financial Officer LaTanya Williams…Communicator Raytheon Seekers

Presentation Outline Client Description Problem Definition What is Infrared Imaging? Project Requirements Design Method Prototype Design Analysis Process Project Spending Time Log Conclusion Raytheon Seekers

More about… Raytheon One of the largest defense electronics contractors in the world. Leader in defense electronics, including: Missiles; Radar, Sensors and Electro-Optics Intelligence, Surveillance and Reconnaissance (ISR) Missile Defense Chairman & CEO: Daniel P. Burnham 2002 Revenue $16.8 Billion 62% of sales to U.S. Department of Defense 79,000 employees worldwide Headquarters located in Lexington, MA Raytheon Seekers

Client Contact Brian Scott B.S.E. in Mechanical Engineering at NAU M.S. in Mechanical Engineering at UofA Employee of Raytheon since graduation Missile Systems – Future Combat Systems Tucson, Arizona Raytheon Seekers

Problem Statement A preliminary design and a proof-of-principal prototype are needed for a window positioning system to be used in a tank-launched projectile. The device must position a small germanium window into an infrared sensor’s optical path to perform Non-Uniformity Compensation. Raytheon Seekers

Project Requirements NUC Mechanism must: Survive 10KG launch acceleration normal to the window face Packaged in 0.235” thick by 2.89” diameter cylinder, excluding electronics Move a 0.50” x 0.44” x 0.04” thick Germanium lens to cover a photocell array Require less than 24 Watts at a maximum of 24 Vdc for less than 1 second Move lens in and out of the field of the array in less than 1 second, and remain in position for 1 second Raytheon Seekers

What Is Infrared Imaging Light at frequencies below visible red are considered infrared All objects emit infrared energy at ordinary temperatures Objects with higher temperatures emit more infrared energy Raytheon Seekers

Infrared Seeker Operation Modern “Heat Seekers”: Employ advanced infrared sensor arrays Utilize computer programs to select, target, and guide munitions towards specific images Raytheon Seekers

Non-Uniformity Compensation (NUC) NUC is necessary to adjust for different pixel sensitivities which could cause erroneous targeting by seeker computer Germanium Lens Moved in Front of IR Array Raw IR Image before NUC Blurred IR Image with Lens in Position Raytheon Seekers

Non-Uniformity Compensation (NUC) Computer algorithm adjusts gain factors of individual pixels so that a uniform image results from a uniform scene NUC Germanium Lens Moved Out of Position Raytheon Seekers

Seeker Head Layout Raytheon Seekers

Rail Gun Test 155mm Howitzer fires projectile into water filled trough to provide firing conditions and “soft catch capability Raytheon Seekers

Acceleration Time Histories Raytheon Seekers

Acceleration Definition Launch Conditions Set Back 10,000G Set Forward 2,000G Lateral Balloting 3,300G Flight Conditions Lateral: 0-3G Vibration: 5G Set Forward Set Back Lateral Balloting Raytheon Seekers

Scope of Design Constraints One quarter subjected to 10,000 G’s weighs approximately 120 lbs. The restricted thickness of the available volume is less than ¼ of an inch Raytheon Seekers

Design Philosophy K.I.S.S. Keep close contact with client Minimize complexity of the design to reduce probability of failure Keep close contact with client Bring attention to potential design problems before it’s too late Raytheon Seekers

Design Process Brainstorming - Mechanism ideas Mechanism Selection - Based on size constraints Modeling - Cardboard & CAD models to assess geometries Analysis - Hand calculations, Adams, COSMOS/M Fabricate Prototype – CNC Raytheon Seekers

Final Design Frame Solenoid Positioning Arm Pin Bushing Return Spring Raytheon Seekers

Final Design

Frame Design Frame supports components and other seeker optics Modified to eliminate unnecessary weight Recessed regions for return spring and counterweight clearance Raytheon Seekers

Frame Design Frame 6061-T6 Aluminum Sult = 45 ksi CNC work done by R&D Specialty Manco Phoenix, Arizona

Selected Solenoid 3 VDC pulling solenoid Electro Mechanisms, Inc Commercially available PO-25 Fits within required dimensions Provides minimum of 2 oz. of force at 3X nominal voltage (18 Watts) Raytheon Seekers

Positioning Arm Positioning Arm Bushing Pin 7075-T6 Aluminum Sult = 82.7 ksi Bushing Oilite Bronze - Oil Impregnated Self Lubricating Bushing Pin AISI 4130 Steel Sult = 106 ksi

Pin Connection Design Press Fit Withstands 120lb Vertical Force Raytheon Seekers

Analysis Justification Deformation of surfaces are within tolerances defined by the optical engineer Deformation of support structure for optics is within tolerance and creates no interference No yielding through cross section of part No ultimate failures occur Raytheon Seekers

Analysis Focus Static Analysis Dynamic Analysis Pin joint withstands launch accelerations Arm deflection does not produce ultimate failure Dynamic Analysis Solenoid and spring actuation times Verification of solenoid adequacy Raytheon Seekers

Finite Element Analysis COSMOS/M 3-D 20 Noded Quadrilateral Elements Body (Acceleration) Load Modeled Positioning Arm & Components 7075-T6 Al Arm Germanium Lens Oilite Brass Bushing Tungsten Counterweight Material properties specified for each component Raytheon Seekers

FEA Mesh

Von Mises Stress Plot smax = 80.3 ksi F.S. = 1.03 Does Not Yield Through Cross-Section Raytheon Seekers

Dynamic Analysis Adams software used for dynamic analysis w.r.t. arm rotation Employed actual solenoid force function curve and spring force Analysis Performed: Actuation & return times Forces due to snubbing of arm rotation Verification of solenoid strength sufficiency over entire actuation distance Raytheon Seekers

Adams Simulation Actuation time = 0.027 sec Spring Return = 0.028 sec

Prototype Cost Cost Per Unit $ 341.96 TOTAL $ 683.92 Machine Work & Parts Frame (2) Arm (2) Pin & Bushing (2) Solenoids (14) Solenoid Screws (144) Miscellaneous (Spring, Wire, etc.) $ 450.00 $ - $ 115.00 $ 89.92 $ 24.00 $ 5.00 TOTAL $ 683.92 Cost Per Unit $ 341.96 Raytheon Seekers

Total Project Spending Modeling Supplies $ 42.00 Prototype Cost $ 683.92 Documentation $ 400.00 Presentation Supplies $ 50.00 Travel & Miscellaneous $ 730.00 TOTAL $1,905.92 Raytheon Seekers

Project Budget Provided Funds by Raytheon Total Project Spending $ 3,000 Total Project Spending $ 1,906 Donation to the College of Engineering & Technology $ 1,094 Raytheon Seekers

Time Log Total Project Hours for Spring Semester 684.5 hrs Avg. Hours Per Team Member: 136.9 hrs Raytheon Seekers

Conclusion The balanced swing arm design is simple and efficient in providing the required lens motion while withstanding the environmental constraints A prototype that meets project specifications will be delivered to Raytheon on time and within budget Raytheon Seekers

Acknowledgements Brian Scott Dr. Ernesto Penado, Advisor Raytheon Missile Systems Dr. Ernesto Penado, Advisor Dr. David E. Hartman, P.E. Dr. John Tester NAU Machine Shop Don McCallum, Daniel, & Rus Raytheon Seekers

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