Estimating the Cost of Space Systems JUST THE BASICS D. B. KANIPE 4/19/2016

Transcription

1 Estimating the Cost of Space Systems JUST THE BASICS D. B. KANIPE 4/19/2016

2 Introdction 2 Iterative process Not an exact science No absolte right answer to the qestion; How mch will it cost? Typical cost drivers Weight (H/W) Lines of code (S/W) Complexity TRL Schedle All estimates based on analogies

3 Cost Estimating Relationships (CERs) 3 What is a CER? A statistically-based, cost-predicting algorithm derived from historical data bases Earlier designs Similar configrations or missions CERs relate the Dependent variables (dollars, labor, hors) to the Independent variables (weight, complexity, amont of code, time) Aggregate of CERs parametric cost model

4 Cost Estimating Methods 4 Detailed bottoms-p cost estimating Most accrate; bt, most time consming Best applied late in program Analogos Estimating Can be applied at any level of design Parametric estimation Based on CERs Best for trade stdies dring conceptal design Caveat #1: CERs only applicable to the range of historical data tilized Caveat #2: Not sefl for projects involving major technological advancements or fndamental paradigm shifts

5 Cost Elements of the Space System 5 DDT&E Space Mission Architectre O&M Prodction Program Costs Spacecraft Segment Lanch Segment Grond Segment Operations & Maintenance Management SE&I Option Z Option B Option A Space System Systems Level Payload (IA&T) Spacecraft Bs (IA&T) Lanch Vehicle Lanch Ops. Facilities Eqipment Software Logistics Management SE&I Personnel Training Maintenance Spares Mission Operations Command, Commnication, and Control DDT&E = Design, Development, Test & Evalation O&M = Operations and Maintenance SE&I = Systems Engineering and Integration IA&T = Integration, Assembly, and Test

6 Types of Costs 6 Non-recrring costs Costs associated with qal test nit or prototype Design, development, fabrication, test Some level of grond spport Does not prodce a flight nit To trn qal nit into a flight nit, + 30% Recrring costs Costs associated with follow on spacecraft H/W and S/W IA&T Lanch spport Flight ops

7 Generic WBS 7 Unmanned Space Mission 1.0 Space Vehicle 2.0 Lanch Vehicle 3.0 Grond Command & Cntl 1.1 Spacecraft Bs Strctre Thermal ADCS EPS Proplsion TT&C IA&T Flight S/W 1.2 Payload Comm Srveillance Mission S/W 1.3 S/C P/L IA&T 4.0 Program Level 4.1 Sys. Eng. 4.2 Prog. Mgt. 4.3 Sys Int. & Test 4.4 Prodct Assrance 4.5 Other 5.0 Flight Spport Operations & Services 7.0 Operations 7.1 PMSE 7.2 Space 7.3 Grond 6.0 Aerospace Grond Eqipment (and pecliar spport eqipment)

8 Phases of Cost Estimating 8 Development Breadboards, brass boards, prototypes, qal nits Design Analysis Test Non-recrring costs Prodction Theoretical first nit (TFU or T1) Prodction nits Manfactre of components Assembly of flight nits Lanch Recrring costs Operations Cost of flying On-going ops Maintenance S/C replacement S/W pdates End-of-life Recrring costs

9 Top-Down Cost Estimating Models 9 Parametric cost estimation Most common (and preferred) method sed in early design phases Models, CERs, and Factors (simplified CERs) Three categories of models Pblicly available special prpose models Government agencies, research centers, niversities Typically available at no cost USCM8, NICM, COCOMO81 Pblicly available general prpose models Private special prpose models

10 Examples Using Factors 10 WBS Element WBS 1.0 Earth Orbital SC (typical) WBS Commnication SC WBS 1.0 Mapping or Meteorological Develop Cost/kg 2010$K TFU/kg 2010$K WBS Observatory WBS 1.0 Positioning, Navigation WBS Science For a small commnications satellite (175kg), the predicted, non-recrring development Cost wold be 429x175=$75M. Recrring TFU Prodction costs shold be 90x175=$16M WBS Element Avg. SLOC per MM* Typical Application WBS Flight S/W 111 SC control WBS 3.0 Grond S/W 340 Grond ops WBS 3.0 Instrment Ops 362 Sensor control WBS 3.0 Image Process 161 Highly algorithmic *Based on 152 hrs/mm The predicted development of 10,000 SLOC of flight S/W shold reqire 10,000/111 or 90 man-months of labor which converts to 90x152 = 13,694 billable hors.

11 Unmanned Space Vehicle Cost Model, Version 8 (USCM8) 11 WBS Element Y=Non-recrring Cost of Development + One Qal Unit Cost Drivers Cost Driver Inpt Range 1.1 SC Bs Y = 110.2(X1) X1=SC Weight (kg) 114-5,127 kg 47% 1.1.1/1.1.2 Strctre & Thermal Control Non-Recrring CERs in FY2010 $K Y = 646(X1) X1=Strctre + Thermal Weight (kg) SEE kg 22% ADCS Y = 342(X1) X1=ADCS Weight (kg) kg 44% EPS Y = 64.3(X1) X1=EPS Weight (kg) 47-1,065 kg 41% Proplsion Y = 20.0(X1) X1=Total RCS Tank Volme (cbic cm) TT&C Y = 26,916 Y=Average TT&C cost. No statistical CER for this element Not given 35% CER based on S-Band telemetry No given

12 NASA s Single-CER QickCost Model 12 WBS Element CER Cost Drivers 1.0 Unmanned Robotic Mission Cost Driver Inpt Range Dry Mass SC bs & inst. (kg) 76 to 14,475 kg Power BOLP in watts 90 to 10,000 W Data % Data rate percentile 0 to 100% Life Design life (months) 6 to 180 months % New Percent new fraction 28% to 130% Planetary No=0, Yes=1 0 for earth orbit 1 for planetary 0 or 1 Year ATP date in for digits 1961 to 2005 Instrment Complexity% Instrment complexity relative to average 0% to 100% Team Team experience (1-4) 1 to 4 SEE (Standard Error Estimate) 41%

13 QickCost Regression Model 13 Y = total cost of development pls one protoflight nit in 2010 dollars Y = x (Dry Mass ) x (Power ) x (2.718 (0.171 x Data %) ) x (2.718 ( x Life) ) x (2.718 (1.52 x New) ) x (2.718 (0.258 x Planetary) ) x 1/(2.718 ( x (Year-1960)) ) x (2.718 (0.467 x InstrComp %) ) x 1/(2.718 (0.237 x Team) ) 1. Cost in millions of 2010 dollars inclding Phase B Phase C/D 2. Incldes all contractor cost throgh fee 3. Incldes NASA fll cost spport 4. Incldes spacecraft bs and instrments DDT&E pls TFU 5. Does not inclde lanch services 6. Add 2% for Phase A 7. Add 9% for Grond Station 8. Add 5% per year for Mission Ops and Data Analysis

14 Estimating Software Costs Using 14 COCOMO81 Originally, software costs were estimated as a percentage of hardware costs COCOMO81 is time tested and maintained by USC Center for Systems and Software Engineering Basic eqation: Effort (MM) = 3.312(KSLOC) 1.2 x πeaf EAF effort adjstment factor Nmber of sorce lines of code (SLOC) mst be estimated πeaf = cmlative prodct of EAFs (EAF 1 x EAF 2 x EAF 3 x.eaf n ) Total of 15 EAFs To develop 10,000 new SLOC --- Effort (MM) = 3.312(10) 1.2 x 1.0 = 52.5 MM If cost per MM = $25,000, cost = $1,312K or $131 per SLOC Assmes a nominal cmlative EAF (nrealistic)

15 Software Development Schedle 15 The nmber of Man Months to develop 10,000 SLOC 52.5 MM COCOMO8 eqation to calclate the development dration Dration (in months) = (MM) 0.32 Dration in calendar months to complete S/W development Reqirements analysis, coding, assembly, testing, docmentation MM = effort in man months derived from eqation on previos slide Using 52.5 MM Dration = x (52.5) 0.32 = 15.5 months Staff loading = 52.5MM/15.5 months = 3.4 persons Cost = 15.5 months x $25,000 $/MM x 3.4 = $1,317K

16 Software Development Cost Drivers (EAFs) 16 Ratings: Very Low Low Nominal High Very High Extra High 1. Reqired reliability 2. Database size 3. Prodct complexity 4. Exection time constraint 5. Main storage constraint 6. Virtal machine volatility 7. Compter trnarond time 8. Analyst capability 9. Applications experience 10. Programmer capability 11. Virtal machine experience 12. Programming langage experience 13. Modern programming practices 14. Use of software tools 15. Reqired development schedle COCOMO Calclator:

17 Estimating Lanch Costs 17 Use existing cost history Select one or more LVs Reqired orbit, payload capability, trajectory, Availability Vehicle Contry Kg to LEO Kg to GTO $ per kg $ per kg LEO $ per kg GTO Small Falcon 1e USA 1,010 N/A $10,900K $10.8K N/A Medim to Intermediate Atlas 2AS USA 8,618 3,719 $132,795K $15.4K $35.7K Heavy Delta 4 Hvy USA 22,560 13,130 $215,000K $9.5K $16.4K

18 Additional Costs 18 Wrap costs added to the prime mission eqipment (PME) costs 3.0 Grond station spport 4.0 Program level System Engineering Project Management Configration Management Etc. (SME The New SMAD, Table 11-24) 7.0 Operations

19 Performance/Cost Trade Space 19 Probably Cstomer s Bdget Marginal performance improvements Maximm Allowable Cost Performance Threshold of acceptable performance Best Bang for the Bck 4 Performance Threshold Expenditre, $.

20 Yo Will Estimate the Cost of LUNA 20 QickCost Regression Model for development costs Prime mission eqipment (PME) COCOMO8 for software costs Lanch vehicle costs Wrap factors: SME The New SMAD, Table Percentage of development cost Only need to inclde those factors that apply Examine reslting nmber for sanity, i.e.; Does it make sense?

21 Wrap Factors 21