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The CKEMSim Integrated Flight Simulation _IFS_

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The CKEMSim Integrated Flight Simulation _IFS_ Powered By Docstoc
					The CKEMSim Integrated Flight
      Simulation (IFS)

               Mac McCrum

 Lockheed Martin Missiles and Fire Control



            mac.mccrum@lmco.com
                (972)603-1286


                                         DPC-836730-1PPT 2/17/2006
                 Developing an IFS -
                 Issues to Address
“What is an IFS?” An IFS is any high fidelity non-real-time all
digital simulation that contains the missile system's flight software.
“Does that mean we need to (or want to) rewrite our engineering
simulation to match the language of our tactical embedded code?”
“If we mix languages, won’t there be compatibility issues? What
kinds of compilers work together?”
“How do we pass data across the interfaces between components
compiled under different languages?”
“For sensor-driven embedded software, the data is much different
from the data passed to the old processor emulation. How do we
simulate the sensor output?”
“What pitfalls and strategies should I know about before I begin?”
“What’s in it for me? Should I argue about this requirement?”
                                                            DPC-836730-2PPT 2/17/2006
                            The CKEM Guidance Methods
                             and Simulation Are Mature
                                                               FLIR FOV
                  MISSILE                                   2.00 X 3.56 DEG                     The Fire Unit:
                 TRACKING MISSILE FLIGHT PATH                                                   • Acquires the target
                 TV FLIR          RF GUIDANCE UPDATE                                            • Launches the missile
 MISSILE                                                                                        • Tracks the missile and target
 INITALIZATION                                                                                    via DayTV and FLIR
                                                                                   SENSOR       • Sends guidance updates to
                                                                                  BORESIGHT
     Fire Unit                                                                                    the missile via the RF Uplink.
                                                                                  TARGET
                                LINE OF SIGHT                                                   The Missile:
                    TV FOV
                 7.5 X 10 DEG
                                            MISSILE                                             • Corrects course by firing
                                                                                                  small steering motors (ACMs)
                                                                                                  in the nose of the missile
                                                                                                • Target is destroyed by kinetic
                                  Development begins from
                                      HVM simulation
                                                                                                  energy.
                                                                     Plume Test 1, 2
                                              FLIR Cal 1                      Launch Shock
The decision to reuse rather                        FLIR Cal 2
                                                                                  TD-1
                                                                                                                    EDF- 0,EDF- 1,EDF- DT-
                                                                                                                    EDF-0,EDF-1,EDF-2, DT-1,
                                                                                  TD-                               DT- DT- DT- DT-
                                                                                                                    DT-2, DT-3, DT-6, DT-7,
                                                    FLIR Cal 3
than rewrite CKEMSim’s legacy                       EDF 1
                                                                                  TD-
                                                                                  TD-1R                             DT- 8,DT- 9,DT- DT- DT-
                                                                                                                    DT-8,DT-9,DT-4, DT-5, DT-10,
                                                             IM-
                                                            IM-1                  TD-
                                                                                  TD-1C                             DT-12, DT-13, DT-15, DT-16,
                                                                                                                    DT-    DT-     DT-   DT-
FORTRAN models was based                            EDF 2
                                                             SR-
                                                            SR-4A                 TD-
                                                                                  TD-1D                      RR-
                                                                                                             RR-1   DTLF, DT-14, DT-11, DT-17,
                                                                                                                           DT-    DT-   DT-
                                                    SR-
                                                    SR- 1A
                                                             AR-
                                                            AR-5                  TD-
                                                                                  TD-1E                                     DT-
                                                                                                                    DTLF2, DT-18
on 18 years and 54 flight tests                     SR-
                                                    SR- 1B
                                                            SR-4B
                                                             SR-                  TD-1F
                                                                                  TD-
                                                                                                             RR-2
                                                                                                             RR-
                                                    SR-
                                                    SR- 2
of refinement and validation                        SR- 3
                                                    SR-
                                                             SR-
                                                            SR-4C
                                                            SR-4D
                                                                                       TD-
                                                                                       TD-3
                                                             SR-                       TD-
                                                                                       TD-3B
under the LOSAT®                                                                         LE-1
                                                                                         LE-
                                                                                                                            CTF-
                                                                                                                            CTF-1
                                                                                                                                      CTF-
                                                                                                                                      CTF-2
and CKEM programs.

                                           ‘88        ‘90      ‘92          ‘94         ‘96     ‘98    ‘00          ‘02         ‘04


                                                                                                                          DPC-836730-3PPT 2/17/2006
                      CKEMSim Data Flow with
                      EOPSIM and CMOFS IFS
                            SCENE                  OPERATOR
                          GENERATOR                 INPUTS
                                                               WEAPON SYSTEM
                                                                 MANAGER
                                             TRACKING
                                                                  (120 Hz)
                                           SYSTEM (120 Hz)
             TARGET
                                               EOPSim
                                                  or                             UPLINK
                                           Hi Fidelity Model                     (30 Hz)


                                      SMOKE &                                                   ICs
                                       PLUME                                     MISSILE GEU
            EQUATIONS
            OF MOTION                                                               (100 HZ)
                                                                 IMU (600 Hz)
                                                                                     CMOFS
                                                                                       or
                                                                                Hi Fidelity Model
                                                       ACMs



                               AERO                             ATMOSPHERE



                                                 PROPULSION

                        MASS



• CKEM SOW required the development of an Integrated Flight Simulation (IFS).
• The existing FORTRAN simulation was adapted by replacing the GEU and Fire Unit
  FORTRAN emulations with embedded code.
• A high fidelity synthetic scene generator was needed to drive the tracker software.
                                                                                             DPC-836730-4PPT 2/17/2006
                       CKEMSim Hardware
                         and Software
   Component       Developed By     Compiler Used        Hardware Required          Comments

                   AMRDEC/                                                   Open source C++ kernel
C++ Model
                                                                             used for simulation and
Developer (CMD)    DESE           Visual C++ Toolkit     PC Processor
                                                                             scientific computing
Executive          Research                                                  development
Tracker Software   Raytheon       Visual Studio 6.0      PC Processor        Operational software
                                  (C/C++ )                                   recompiled for PC
Synthetic Scene    LMMFC, with    Visual Studio.net      nVidia Graphics     Produces a data stream
Generator          data from      2003 (C++),            Card with 6600 or   identical to the FLIR and
                   AMRDEC         Nvidia CG v 1.3 with   6800 series chips   DayTV output
                                  OpenGL version 2.0     (with 12-bit
                                                         blending + CG),
                                                         PC Processor
CKEM Missile       LMMFC          Visual Studio 6.0      PC Processor        Operational software
Operational Flight                (C++)                                      recompiled for PC
Software
Missile and Target LMMFC          Lahey Fortran 95       PC Processor        Legacy models
Truth Models                      v5.6,
                                  Visual C++ Toolkit

                                                                                     DPC-836730-5PPT 2/17/2006
                          CMOFS to FORTRAN/C++ Attitude
                           Control Motor Model Interface
• CMOFS issues commands to fire Attitude Control Motors to correct course.
• This interface is typical of the interfaces developed for scene generation and tracker software.
gpa_subsys.f                                                             #include acmgpa_common.inc
                                         acmgpa_common.inc
                                         common acmgpa nsel, idacm(4), tfire_gpa(4), dt_acm_fire(4)

                    dtsim_mofs_interface(
               call dtsim_mofs_interface( . . . nsel, idacm, tfire_gpa, dt_acm_fire)

dtsim_mofs_interface.cpp                                                                             Extern "C"
 ACMs_to_Fire_Next_CC_Type ACMs                                                                      {
                                                                                                     include "dtsim_mofs_interface.h”;
         Execute_CMOFS_Comp_Cycle(
         Execute_CMOFS_Comp_Cycle( . . . ,ACMs)                                                      };
                                                                                                          dtsim_mofs_interface.h
      #include cmofs_interface.h
   cmofs_interface.h                                      idacm[0] = ACMs.ACM_1.ACM_To_Fire;                      dtsim_mofs_interface_(
                                                                                                           void dtsim_mofs_interface_(
                                                          idacm[1] = ACMs.ACM_2.ACM_To_Fire;                 int &nsel,
     struct Acm_To_Fire_Record_Type                       idacm[2] = ACMs.ACM_3.ACM_To_Fire;                 int idacm[4],
     {                                                    idacm[3] = ACMs.ACM_4.ACM_To_Fire;                 double tfire_gpa[4],
              time- to-
       double time-to-Fire // since time of breakwire                                                        double dt_acm_fire[4]
                                                          tfire_gpa[0] = ACMs.ACM_1.Time_To_Fire;
       int ACM_To_Fire // Physical ACM number                                                              )
                                                          tfire_gpa[1] = ACMs.ACM_2.Time_To_Fire;
     };
                                                          tfire_gpa[2] = ACMs.ACM_3.Time_To_Fire;
                                                          tfire_gpa[3] = ACMs.ACM_4.Time_To_Fire;
     struct ACMs_to_Fire_Next_CC_Type                     nsel=0
     {                                                    for (i=0;i<4;i++) {
       ACM_To_Fire_Record_Type ACM_1;
                                                            if (idacm[i] >0) {
       ACM_To_Fire_Record_Type ACM_2;
                                                               nsel=nsel++; // count up acm selected
       ACM_To_Fire_Record_Type ACM_3;
                                                               dt_acm_fire[i] = tfire_gpa[i] – gpatm_tg;
       ACM_To_Fire_Record_Type ACM_4;
                                                            }
     }                                                    }
                                                                                                                    DPC-836730-6PPT 2/17/2006
   Visualization of a
Simulated Engagement




                        DPC-836730-7PPT 2/17/2006
                Lessons Learned
• Intermixed languages work together reasonably well.

• Operational code needed to be revised to reinitialize
  between Monte Carlo samples.

• Graphics cards with the same chip, but different model
  numbers or different drivers, produced different results.

• Integration went smoothly because a clean interface was
  established up front.

• If you need a scene generator, find someone who’s done it
  before successfully. Chances are even they will find it very
  difficult.

                                                      DPC-836730-8PPT 2/17/2006
                            Benefits
• Prior capabilities of the simulation were retained.
    − Probability of hit analysis, ACM consumption rates, sensitivity
      analysis
    − HWIL driver, Raytheon SIL
    − Mission planning, range safety, algorithm development

• The synthetic scene generator can test the tracker software with a
  wider variety of flight conditions than just using flight test imagery
  and HWIL.
    − Can also use Monte Carlo methods
    − Specific Tracker algorithm problems exposed and fixed to date
      include inefficiencies in the search rate, and errant missile track
      rejection due to sporadic smoke obscuration
    − Synthetic imagery is the only way to test multigrain motor plume
      imagery before flight

• Allows HWIL testing to focus on timing and host processor issues.

• Closer match between simulation and embedded code = increased
  credibility.
                                                               DPC-836730-9PPT 2/17/2006

				
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