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Raising the Bar: Equipping DOD Testers to Excel with DOE

Process. Plan. Produce. Ponder. Cause-Effect (CNX) Diagram. Materials. Manpower. Measurements. Response to Effect. Causes. Causes. Milieu (Environment). Methods. Machines. Raising the Bar: Equipping DOD Testers to Excel with DOE. presented to: Service T&E Executives

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Raising the Bar: Equipping DOD Testers to Excel with DOE

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  1. Process Plan Produce Ponder Cause-Effect (CNX) Diagram Materials Manpower Measurements Response to Effect Causes Causes Milieu (Environment) Methods Machines Raising the Bar: Equipping DOD Testers to Excel with DOE presented to: Service T&E Executives October 2009 Greg Hutto Wing Ops Analyst, 46th Test Wing gregory.hutto@eglin.af.mil

  2. Bottom Line Up Front • Test design is not an art…it is a science • Talented scientists in T&E Enterprise however…limited knowledge in test design…alpha, beta, sigma, delta, p, & n • Our decisions are too important to be left to professional opinion alone…our decisions should be based on mathematical fact • 53d Wg, AFOTEC, AFFTC, and 46 TW/AAC experience • Teaching DOE as a sound test strategy not enough • Senior Executive Leadership (Company, SPO & Test) is key • Purpose: DOD adopts experimental design as the default approach to test, wherever it makes sense • Exceptions include demos, lack of trained testers, no control We have the skills, cadre, courseware & infrastructure to do what needs to be done. Only direction & seed funds are required …

  3. Background -- Greg Hutto • B.S. US Naval Academy, Engineering - Operations Analysis • M.S. Stanford University, Operations Research • USAF Officer -- TAWC Green Flag, AFOTEC Lead Analyst • Consultant -- Booz Allen & Hamilton, Sverdrup Technology • Mathematics Chief Scientist -- Sverdrup Technology • Wing OA and DOE Champion – 53rd Wing, now 46 Test Wing • USAF Reserves – Special Assistant for Test Methods (AFFTC/CT) and Master Instructor in DOE for USAF TPS Practitioner, Design of Experiments -- 20 Years Selected T&E Project Experience – 23+ Years • Green Flag EW Exercises ‘79 • F-16C IOT&E ‘83 • AMRAAM, JTIDS ‘ 84 • NEXRAD, CSOC, Enforcer ‘85 • Peacekeeper ‘86 • B-1B, SRAM, ‘87 • MILSTAR ‘88 • MSOW, CCM ’89 • Joint CCD T&E ‘90 • SCUD Hunting ‘91 • AGM-65 IIR ‘93 • MK-82 Ballistics ‘94 • Contact Lens Mfr ‘95 • Penetrator Design ‘96 • 30mm Ammo ‘97 • 60 ESM/ECM projects ‘98--’00 • B-1B SA OUE, Maverick IR+, F-15E Suite 4E+,100’s more ’01-’06

  4. Overview • Four Challenges of Test – 80% JPADS example • 3 DOE Fables Illustrating T&E Transformed • Way Ahead - Policy & Deployment Discussion • Summary • Q&A

  5. What are Statistically Designed Experiments? • Purposeful, systematic changes in the inputs in order to observe corresponding changes in the outputs • Results in a mathematical model that predicts system responses for specified factor settings in the presence of noise

  6. Four Challenges faced by any test How many? Depthof Test –effect of test size on uncertainty Which Points? Breadth of Testing – spanning the vast employment battlespace How Execute? Order of Testing – insurance against “unknown-unknowns” What Conclusions? Test Analysis– drawing objective, scientific conclusions while controlling noise DOE effectively addresses all these challenges! Why DOE? One Slide…DOE Gives Scientific Answers to Four Fundamental Test Challenges

  7. Today’s Example – Precision Air Drop System The dilemma for airdropping supplies has always been a stark one. High-altitude airdrops often go badly astray and become useless or even counter-productive. Low-level paradrops face significant dangers from enemy fire, and reduce delivery range. Can this dilemma be broken? A new advanced concept technology demonstration shows promise, and is being pursued by U.S. Joint Forces Command (USJFCOM), the U.S. Army Soldier Systems Center at Natick, the U.S. Air Force Air Mobility Command (USAF AMC), the U.S. Army Project Manager Force Sustainment and Support, and industry. The idea? Use the same GPS-guidance that enables precision strikes from JDAM bombs, coupled with software that acts as a flight control system for parachutes. JPADS (the Joint Precision Air-Drop System) has been combat-tested successfully in Iraq and Afghanistan, and appears to be moving beyond the test stage in the USA… and elsewhere. • Capability: • Assured SOF re-supply of material • Requirements: • Probability of Arrival • Unit Cost $XXXX • Damage to payload • Payload • Accuracy • Time on target • Reliability … Just when you think of a good class example – they are already building it! 46 TS – 46 TW Testing JPADS

  8. 1906 – W.T. Gossett, a Guinness chemist Draw a yeast culture sample Yeast in this culture? Guess too little – incomplete fermentation; too much -- bitter beer He wanted to get it right 1998 – Mike Kelly, an engineer at contact lens company Draw sample from 15K lot How many defective lenses? Guess too little – mad customers; too much -- destroy good product He wanted to get it right A beer and a blemish …

  9. In all our testing – we reach into the bowl (reality) and draw a sample of JPADS performance Consider an “80% JPADS” Suppose a required 80% P(Arrival) Is the Concept version acceptable? We don’t know in advance which bowl God hands us … The one where the system worksor, The one where the system doesn’t The central challenge of test – what’s in the bowl? The central test challenge …

  10. Let’s draw a sample of _n_ drops How many is enough to get it right? 3 – because that’s how much $/time we have 8 – because I’m an 8-guy 10 – because I’m challenged by fractions 30 – because something good happens at 30! Let’s start with 10 and see … Start -- Blank Sheet of Paper => Switch to Excel File – JPADS Pancake.xls

  11. Suppose we fail JPADS when it has 4 or more misses We’ll be wrong (on average) about 10% of the time We can tighten the criteria (fail on 7) by failing to field more good systems We can loosen the criteria (fail on 5) by missing real degradations Let’s see how often we miss such degradations … A false positive – declaring JPADS is degraded (when it’s not) -- a In this bowl – JPADS performance is acceptable JPADS Wrong ~10% of time

  12. Use the failure criteria from the previous slide If we field JPADS with 6 or fewer hits, we fail to detect the degradation If JPADS has degraded, with n=10 shots, we’re wrong about 65% of the time We can, again, tighten or loosen our criteria, but at the cost of increasing the other error A false negative – we field JPADS (when it’s degraded) -- b In this bowl – JPADS P(A) decreased 10% -- it is degraded JPADS Wrong 65% of time

  13. Combining, we can trade one error for other (a for b) We can also increase sample size to decrease our risks in testing These statements not opinion –mathematical fact and an inescapable challenge in testing There are two other ways out … factorial designs and real-valued MOPs We seek to balance our chance of errors JPADS Wrong 10% of time JPADS P(A) Wrong 65% of time Enough to Get It Right: Confidence in stating results; Power to find small differences

  14. A Drum Roll, Please … • For a = b = 10%, d = 10% degradation in PA N=120! • But if we measure miss distance for same confidence and power N=8

  15. RMS Trajectory Dev Hits/misses P(payload damage) Miss distance (m) Outputs (MOPs) Inputs (Conditions) JPADS Concept A B C … Tgt Sensor (TP, Radar) Payload Type Platform (C-130, C-117) Challenge 2: Breadth -- How Do Designed Experiments Solve This? Statistician G.E.P Box said … “All math models are false …but some are useful.” “All experiments are designed … most, poorly.” Designed Experiment (n). Purposeful control of the inputs (factors) in such a way as to deduce their relationships (if any) with the output (responses). Test JPADS Payload Arrival

  16. Systems Engineering Question: Does JPADS perform at required capability level across the planned battlespace? Battlespace Conditions for JPADS Case 12 Dimensions - Obviously a large test envelope … how to search it?

  17. Populating the Space – Traditional Test Designs Altitude Altitude OFAT Typical Use Cases Mach Mach Altitude And … the always popular DWWDLT* Change variables together: best, worst, nominal Mach * Do What We Did Last Time

  18. Populating the Space - DOE Altitude Altitude ResponseSurface Factorial Mach Mach Altitude single point Optimal replicate Mach

  19. More Variables - DOE Altitude Altitude 3-D Factorials 2-D Range Mach Mach 4-D Range Altitude Weapon – type A Weapon – type B Mach

  20. C B A Even More Variables (here – 6) F – + – + D – E +

  21. C B A Efficiencies in Test - Fractions F – + – + D – E +

  22. We have a wide menu of design choices with DOE Optimal Designs Response Surface Full Factorials Space Filling Fractional Factorials JMP Software DOE Menu

  23. Problem context guides choice of designs Space-Filling Designs Optimal Designs Response Surface Method Designs Fractional Factorial Designs # Levels Per Factor Needed Classical Factorials Number of Factors Constraints/Complexity of Surface

  24. 2 reps 2 vars 1 reps 3 vars ½ rep 4 vars Challenge 2: Choose Points to Search the Relevant Battlespace 4 reps 1 var • Factorial (crossed) designs let us learn more from the same number of assets • We can also use Factorials to reduce assets while maintaining confidence and power • Or we can combine the two • How to support such an amazing claim? All four Designs share the same power and confidence => Switch to Excel File – JPADS Pancake.xls

  25. Task performance (unrandomized) Task performance (randomized) Challenge 3: What Order? Guarding against “Unknown-Unknowns” Learning • Randomizing runsprotects from unknown background changes within an experimental period (due to Fisher) Good run sequence time easy runs hard runs

  26. detection (no blocks) detection (blocks) large target small target Blocks Protect Against Day-to-Day Variation Day1 Day 2 visibility Good time run sequence • Blockingdesigns protects from unknown background changes between experimental periods (also due to Fisher)

  27. Challenge 4: What Conclusions - Traditional “Analysis” • Table of Cases or Scenario settings and summary statistics • Graphical Cases summary of averages • Errors (false positive/negative)? • Linking cause & effect: Why?

  28. How Factorial Matrices Work -- a peek at the linear algebra under hood • We set the X settings, observe Y • Solve for b s.t. the error (e) is minimized Simple 2-level, 2 X-factor design Where y is the grand mean, A,B are effects of variables alone and AB measures variables working together • To solve for the unknown b’s, X must be invertible • Factorial design matrices are generally orthogonal, and therefore invertible by design

  29. With DOE, we fit an empirical (or physics-based) model • Very simple to fit models of the form above (among others) with polynomial terms and interactions • Models fit with ANOVA or multiple regression software • Models are easily interpretable in terms of the physics (magnitude and direction of effects) • Models very suitable for “predict-confirm” challenges in regions of unexpected or very nonlinear behavior • Run to run noise can be explicitly captured and examined for structure

  30. Analysis using DOE: CV-22 TF Flight Gross Weight Radar Measurement INPUTS (Factors) OUTPUTS (Responses) Airspeed PROCESS: Set Clx Plane Deviation Turn Rate Set Clearance Plane Crossing Angle Ride Mode TF / TA Radar Performance Pilot Rating Nacelle Terrain Type Noise

  31. Analysis Using DOE Gross Turn SCP Pilot Weight SCP Rate Ride Airspeed Dev Ratings 55 300.00 0.00 Medium 160.00 5.6 4.547.5 500.00 0.00 Medium 160.00 0.5 4.847.5 300.00 4.00 Medium 160.00 7.5 4.255 500.00 4.00 Medium 160.00 2.3 4.847.5 300.00 0.00 Hard 160.00 5.2 4.255 500.00 0.00 Hard 160.00 1.2 4.655 300.00 4.00 Hard 160.00 12.0 3.247.5 500.00 4.00 Hard 160.00 6.7 3.447.5 300.00 0.00 Medium 230.00 4.0 4.855 500.00 0.00 Medium 230.00 0.2 5.455 300.00 4.00 Medium 230.00 15.0 2.847.5 500.00 4.00 Medium 230.00 8.3 3.255 300.00 0.00 Hard 230.00 5.8 4.547.5 500.00 0.00 Hard 230.00 1.9 5.047.5 300.00 4.00 Hard 230.00 16.0 2.055 500.00 4.00 Hard 230.00 12.0 2.547.5 400.00 2.00 Medium 195.00 4.0 4.247.5 400.00 2.00 Hard 195.00 7.2 3.755 400.00 2.00 Medium 195.00 6.6 4.455 400.00 2.00 Hard 195.00 7.7 3.8

  32. Interpreting Deviation from SCP: speed matters when turning Noise Note that we quantify our degree of uncertainty – the whiskers represent 95% confidence intervals around our performance estimates. An objective analysis – not opinion

  33. Correctly Quantifying Radar Performance ResultsSCP Deviation Estimating Equation Prediction Model - Coded Units (Low=-1, High=+1) Deviation from SCP = +6.51 -2.38 * SCP +3.46 * Turn Rate +1.08 * Ride +1.39 * Airspeed +0.61 * Turn * Ride +1.46 * Turn * Airspeed Regression Model Notes: - significant regression coefficients – what matters, direction, magnitude - missing coefficients – signify factors do not matter in this space - our design a and b rates control our risks of false positives and negatives

  34. Outcomes can be Validated with Performance Predictions Name Setting Low Level High Level SCP 460.00 300.00 500.00 Turn Rate 2.80 0.00 4.00 Ride Hard Medium Hard Airspeed 180.00 160.00 230.00 Noise Prediction 95% PI low 95% PI high Deviation from SCP6.96 4.93 8.98 Pilot Ratings3.62 3.34 3.90

  35. Test as Science vs. Art: Experimental Design Test Process is Well-Defined Desired Factors and Responses Planning: Factors Desirable and Nuisance Design Points Discovery, Understanding Prediction, Re-design Model Build Randomize & Block -> Results and Analysis Test Matrix

  36. Caveat – we need good science!Good news – we have good science • We understand operations, aero, mechanics, materials, physics, electro-magnetics … • To our good science, DOE adds the Science of Test Bonus: Match faces to names – Ohm, Oppenheimer, Einstein, Maxwell, Pascal, Fisher, Kelvin

  37. IR Sensor Predictions Ballistics 6 DOF Initial Conditions Wind Tunnel fuze characteristics Camouflaged Target JT&E ($30M) AC-130 40/105mm gunfire CEP evals AMRAAM HWIL test facility validation 60+ ECM development + RWR tests GWEF Maverick sensor upgrades 30mm Ammo over-age LAT testing Contact lens plastic injection molding 30mm gun DU/HEI accuracy (A-10C) GWEF ManPad Hit-point prediction AIM-9X Simulation Validation Link 16 and VHF/UHF/HF Comm tests TF radar flight control system gain opt New FCS software to cut C-17 PIO AIM-9X+JHMCS Tactics Development MAU 169/209 LGB fly-off and eval Characterizing Seek Eagle Ejector Racks SFW altimeter false alarm trouble-shoot TMD safety lanyard flight envelope Penetrator & reactive frag design F-15C/F-15E Suite 4 + Suite 5 OFPs PLAID Performance Characterization JDAM, LGB weapons accuracy testing Best Autonomous seeker algorithm SAM Validation versus Flight Test ECM development ground mounts (10’s) AGM-130 Improved Data Link HF Test TPS A-G WiFi characterization MC/EC-130 flare decoy characterization SAM simulation validation vs. live-fly Targeting Pod TLE estimates Chem CCA process characterization Medical Oxy Concentration T&E Multi-MDS Link 16 and Rover video test It applies to our tests: DOE in 50+ operations over 20 years

  38. Four Challenges faced by any test How many? A: sufficient samples to control our twin errors – false positives & negatives Which Points? A: span/populate the battle-space while linking cause and effect with orthogonal run matrices How Execute? A: Randomize and Block runs to exclude effects of the unknown-unknowns What Conclusions? A: build math-models* of input/output relations, quantifying noise, controlling error DOE effectively addresses all these challenges! Recap - Scientific Answers to Four Fundamental Test Challenges * Many model choices: regression, ANOVA, mixed, Gen Lin Model, CART, Kriging, MARS

  39. Process Plan Produce Ponder Cause-Effect (CNX) Diagram Materials Manpower Measurements Response to Effect Causes Causes Milieu (Environment) Methods Machines Three DOE Stories for T&E Development: AIM-9X Block II R&D and PWE sim Flight Test: F-16 Ventral Fin vibration reduction Integrated Test: F-15E Strike Eagle Suite 4E+ We’ve selected these from 1000’s to show T&E Transformation

  40. Notional 520 grid Notional DOE grid Case: AIM-9X Blk II Simulation Pk Predictions Update Test Objective: • Validate simulation-based Pk • “520 Set”: 520 x 10 reps x 1.5 hr/rep = 7800 CPU-hours = 0.89 CPU-years • Block II contemplates “1380 set” • 1 replicate-1 case: 1 hour => 1380*1*10 =13,800 hours = 1.6 CPU-years • DOE Approach: • Collaborate: DT/OT/SPO/KTR willing to try • We’ve shown: many conditions have no effect, 1-3 reps max, shot grid 10x too fine • Raytheon locates OR-types to lead DOE effort • Projection – not 13,800, but 1000 hours max saving 93% of resources • Excellent choice for both R&D and PWE sets • Good progress – but a little push desirable • Next Steps: • Raytheon continues to learn/apply DOE …

  41. Case: Reduce F-16 Ventral Fin Fatigue from Targeting Pod Face-Centered CCD Test Objective: • blah Embedded F-CCD Expert Chose 162 test points Ventral fin • DOE Approach: • Many alternate designs for this 5-dimensional space (a, b , Mach , alt, Jets on/off) • Results: • New design invented circa 2005 capable of efficient flight envelope search • Suitable for loads, flutter, integration, acoustic, vibration – full range of flight test • Experimental designs can increase knowledge while dramatically decreasing required runs • A full DOE toolbox enables more flexible testing

  42. Acquisition: F-15E Strike Eagle Suite 4E+ (circa 2001-02) Test Objectives: • Qualify new OFP Suite for Strikes with new radar modes, smart weapons, link 16, etc. • Test must address dumb weapons, smart weapons, comm, sensors, nav, air-to-air, CAS, Interdiction, Strike, ferry, refueling… • Suite 3 test required 600+ sorties DOE Approach: • Build multiple designs spanning: • EW and survivability • BVR and WVR air to air engagements • Smart weapons captive and live • Dumb weapons regression • Sensor performance (SAR and TP) Results: • Vast majority of capabilities passed • Wrung out sensors and weapons deliveries • Dramatic reductions in usual trials while spanning many more test points • Moderate success with teaming with Boeing on design points (maturing) Source: F-15E Secure SATCOM Test, Ms. Cynthia Zessin, Gregory Hutto, 2007 F-15 OFP CTF 53d Wing / 46 Test Wing, Eglin AFB, Florida

  43. Strike Weapons Delivery a Scenario Design Improved with DOE

  44. 19 Month Progress Report on DOE “Proof Phase” – No Failures

  45. A Strategy to be the Best …How we are currently deploying DOE • Wing-based change strategy (vice Command) • Train Leadership in Statistical Test Thinking • Unit Policy endorses best test strategy (DOE) • Train & mentor total team • Partner with AFIT, COA, & University for R&D • Revise AF Acquisition policy & procedures • Share these test improvements: Targets • HQ AFMC • ASC & ESC • Service DT&E Adopting DOE • 53d Wing & AFOTEC • 18 FTS (AFSOC) • RAF AWC • DoD OTA: DOT&E, AFOTEC, ATEC, OPTEVFOR & MCOTEA • AFFTC & TPS • 46 TW & AAC • AEDC

  46. 53d Wing Policy Model: Test Deeply & Broadly with Power & Confidence • From 53d Wing Test Manager’s Handbook*: “While this [list of test strategies] is not an all- inclusive list, these are well suited to operational testing. The test design policy in the 53d Wing supplement to AFI 99-103 mandates that we achieve confidence and power across a broadrange of combat conditions. After a thorough examination of alternatives, the DOE methodology using factorial designs should be used whenever possible to meet the intent of this policy.” Focus: DOE is a means to an end – require the fruit of a well-designed experiment, not the method (or we’ll get “DOE”) * Original Wing Commander Policy April 2002

  47. March 2009: OTA Commanders Endorse DOE for both OT & DT “Experimental design further provides a valuable tool to identify and mitigate risk in all test activities. It offers a framework from which test agencies may make well-informed decisions on resource allocation and scope of testing required for an adequate test. A DOE-based test approach will not necessarily reduce the scope of resources for adequate testing. Successful use of DOE will require a cadre of personnel within each OTA organization with the professional knowledge and expertise in applying these methodologies to military test activities. Utilizing the discipline of DOE in all phases of program testing from initial developmental efforts through initial and follow-on operational test endeavors affords the opportunity for rigorous systematic improvement in test processes.” “Apply DoE as key ingredient in formulation of meaningful integrated testing”

  48. July 2009: 46 TW Adopts DOE as default method of test

  49. Journeymen Testers = “Black Belts” We Train the Total Test Team … but first, our Leaders! Leadership Training (=“Champion”) • DOE for Leaders (2-4 Hours) • Awareness Training (= “Green Belt”) • Introduction to Designed Experiments (engineers - 2 days) 150+ Grads Engineer/OR DOE Practitioner Training • 10 sessions and 1 week each • Reading--Lecture--Seatwork • DOE 0 - Stats Review (1 week) • Random Variables and Distributions • Descriptive & Inferential Statistics • Thorough treatment of t Test, 1 way ANOVA • Applied DOE I and II (1 week each) • Advanced Undergraduate treatment • Graduates know both how and why 1500+ Grads 1000+ Grads

  50. Seasoning - Mentoring & Cont. Training (=“Master Black Belts”) • Weekly seminars online • Topics wide ranging • New methods • New applications • Problem decomposition • Analysis challenges • Reviewing the basics • Case studies • Advanced techniques • DoD web conferencing • Q&A session following • Monday 1400-1500 CR 22 Bldg 1 or via DCO at desk

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