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Developement Of An Instrument Landing Simulation Using MATLAB

1. Constant28 an excellent model for testing and calibrating the Figure 24 Instrument Model instruments and channels 3 2 1 6 Graphics Model left The graphics model receives the position and S Function rotation from the SixDOF model as well It sends the information over the Ethernet to the three graphics md UN aem S Function1 computers using UDP The model waits for the graphics Mux1 to initialize before it starts the simulation It also does a al gt l K right conversion from aircraft axis to world axis Figure 25 SFanelond Mux2 Figure 25 Graphics Model shows the graphics model with the three outgoing signals to each computer that send the aircraft s position and orientation as well as whether to keep the graphics running On the client side 26 different scenarios can be chosen such as an instrument landing simulation to the Salinas airport in Monterey or a Korean database filled with mountains and canyons to fly through 3 2 1 7 ILS Model The ILS model in Figure 26 simulates an ILS transmitter located at the end of the runway The model receives the aircraft s position and calculates the deviation off glide slope and runway centerline based on the airport s location and heading It then displays the angle deviations on the CDI and ILS Figure 26 ILS
2. static void mdlInitializeSampleTimes SimStruct S ssSetSampleTime S 0 INHERITED SAMPLE TIME ssSetOffsetTime S 0 0 0 define MDL START Hif defined MDL START Function mdlstart 64 Initialize the state variables I static void mdlStart SimStruct S This is where you add code for the first time the simulation starts For this simple file there is no need for any code in this section endif MDL_START Function mdlOutputs jj A Abstract This section assigns the input variables to pointers in the u array and assigns the outputs to the y array The speed of sound and Mach k Number is calculated in the Calculate function Inputs RFuelCap uPtrs 0 LFuelCap uPtrs 1 d EngType uPtrs 2 Np uPtrs 3 RThrottle uPtrs 4 LThrottle uPtrs 5 Tsl uPtrs 6 5 TSFCsINAB uPtrs 7 65 TSFCsIAB uPtrs 8 rho uPtrs 9 x a uPtrs 10 Vtrue uPtrs 11 Outputs y 0 RFuelFlo X y 1 LFuelFlo ii y 2 RThrust E y 3 LThrust y 4 RNoz yl5 LNoz y 6 RRPM y 7 LRPM E y 8 RTemp i y 9 L Temp static void mdlOutputs SimStruct S int T tid InputRealPtrsType uPtrs ssGetInputPortRealSignalPtrs S 0 real_T y ssGetOutputPortRealSignal S 0 Read in the Inputs RFuelCap uPtrs 0 66 LFuelCap uPtrs 1 EngType uPtrs 2 Np uPtrs 3 RThrottle uPtrs 4 LThrottle uP
3. if message len 0 fprintf stdout slave_get_data error reading from socket n return G_FAILURE strcpy cameraname PILOT GV_obi_set_position ownship amp host_data ownpos GV_obi_set_rotation ownship amp host_data ownrot GV cam ing by name cameraname amp camera GV chn set camera channel 1 camera return status 111 B 7 ModHostData h FREE SE GE GE GE o ok ok ok ok ok aj o os k a ls ls ls ls ls oe oe oe oe k k k ohe k k k k k kK k k K k k K k k k K k k K k ok sk aj K K k k k MODULE modhostdata h AUTHOR S Robert A Barger Jon Tonkyro DATE May 20 2000 Copyright c ALL RIGHTS RESERVED REVISION HISTORY REVAUTHOR DATE DESCRIPTION 0 JT amp RAB 5 20 00 Creation amp Tested NOTO include gv types h gt struct Host data Continous data from host sent every frame X G Position OWNPOS ene Ownship vehicle position Ei G Rotation ownroty wr Ownship vehicle rotation angles e n n s eS 1 to QUIT now 7 J 112 113
4. r sgrt x x y y Thetal atan y x 91 Theta2 pi Thetal Theta3 2 pi APpsi pi 180 Theta4 atan z x lambda 90 pi 180 Thetal Theta3 a cos lambda r CDVert 57 3 sin a r CDI CDVert Same angle different scale Calculate CDHor CDHor 57 3 Theta4 GlideSlope pi 180 return Function mdlTerminate Abstract No termination needed but we are required to have this routine sl static void mdlTerminate SimStruct S 92 ifdef MATLAB MEX FILE Is this file being compiled as a MEX file include simulink c MEX file interface mechanism else Hinclude cg sfun h Code generation registration function ftendif 93 B 4 Server c po oko oko ok ok ok ok aj aj aj aj aj ls ls ds ls ls ls o oe oe o k k kk k k k k k KK k k K k k K k k K K k k ok ok ok sk aj K K k k k MODULE server c AUTHOR S Robert A Barger Jon Tonkyro DATE May 8 2000 Copyright c ALL RIGHTS RESERVED REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 JT 5 05 00 Creation into C Format amp Tested 1 RAB 5 08 00 Creation into S Function Format S mex See simulink src sfuntmpl doc Copyright c 1990 1998 by The MathWorks Inc All Rights Reserved Revision 1 3 This S function block sends the position and orientation of the aircraft to the graphics client computers Eagle Pheagle a
5. Monterey Database viii ias da dai n 32 4 1 2 Instrument Landing Simulation eere 22 Figure 30 Takeoff Landing Scenario ee 33 Figure 91 CDI SES a 34 AD Rear GORI is syn Says Sot Em 34 4 3 Heads Up DiISplay irsi os tur Eo vn aperto te e Ret a Tane aia Genser QURE 35 44 Combat Stmiulatof citer epe pbi ntu eben do o 35 4 5 Combat Simulation ATA viii ias 35 AO TEO EOS A A e 36 Figure 32 P oje toP SUDAN epit A 36 Figure 33 LhreesProjector Display ti elis 37 AJ Cali bration PET ensanse a ds 37 4 71 Instrument Calibration nannan bte S86 pass aa 37 Table 1 Instrument Checklist eerte te eite tete 38 viii 4 7 2 Throttle Calibrati0n ooocncccncnnononunanocccncnnnnonananacocnnnnnnonananicicn nnns 38 Figure 34 Initial Throttle Readings ninen 39 Figure 35 Throttle Analog Output eee 40 Figure 36 Corrected Throttle Output lt 40 4 8 Graphical User Interface GUI 41 5 Simulator Implementation ccsccssssccssssscssssccssssccssssccssssscssscssssssssscssssscssssessssees 42 A E A ements 42 5 2 Flight Control System Designissa Kasta saa saa essee asetan 43 Figure 37 Glide Slope SUAR dou mA A A A As 43 5 3 VER IER Landing SImulation samassa ovessa so a aves san kesken ema Nastan 43 5 4 Guidanee Q Control ars A S iisa das sae 44 OM 811 114 111311 moe 45 1 Introduction Flight simulations take years to develop In industry a team of 50
6. done before The last aspect of the PhEagle Virtual Library is its documentation database This will include any thesis work senior projects student work or pertinent information 3 2 1 Models Within the PhEagle Virtual Library are model sections describing each model in detail Included in each section are the Simulink model source code executable d11 and any documentation Any updates to the source code or models is to be updated to the directory for that model so that all models and code is current The following are the models entered so far in the simulation 3 2 1 1 Stick Model The stick model in Figure 20 reads the inputs from the stick rudder and throttles The input is on a range of 5 volts and outputs 1 0 in digital S Function f Pu dr form to be run in Simulink for the stick and rudder in pedals For the throttle inputs the output is in percent of maximum thrust This will base the e D Figure 20 Stick Model throttle setting from O to 1 23 3 2 1 2 Engine Model The engine model in Figure 21 computes the thrust generated by the aircraft s engine s based on the throttle setting altitude and static seal level thrust The engine can either be a propeller turboprop high by pass ratio engine or jet engine with afterburner or without Other necessary inp
7. 4 inputs gamma R Temp and velocity then calculates and returns 2 outputs Speed of Sound Mach Number 47 Documentation Introduction to Pheagle Flight Simulator Download Manual Bob Barger s Senior Project Instrument Calibration Download Report Doug Hiranka s Thesis An Integrated Modular Simulation System for Education and Research A thesis describing the initial development of the PhEagle simulator Download PDF Get Acrobat Reader For more information or questions about the system contact Aaron Munger Grad student Flexible structures Bob Barger Grad Student Flight Simulation Doug Hiranaka Alumni Controls Flight Simulation Last updated 6 6 00 48 The PhEagle Flight Simulation The PhEagle Simulation is a Six Degree Of Freedom 6 DOF Non Linear Simulation The Simulation is run within Matlab using compiled C code It reads in a standard data file which contains an aircraft s stability derivatives Imbedded in the simulation is a stick model to read in the inputs An eninge model simulates a basic engine by calculating thrust and engine attributes A standard atmosphere model determines the pressure temperature and density based on a specific altitude A 6 Dof model calculates the aircraft s new position and orientation Finally an instrument model displays the information to the pilot on the instrument panel 49 Stick Model This page describes the stick model and how it works Below is the
8. AA RG u EK a s ksm da QUE 4 2 simulation PLOW erc 5 Figure 2 Simulation Flow Schemdtlic ida dead Sosa ans 5 2 1 Analog Input usina in dais 6 Figure 3 Analog Input Schematic AA o at qe psi 6 ZACK n 7 Figure d Flo STICK S cs uates ecd TA 7 Figure 5 Stick Torque Motor s tiit isa hine p 8 2 1 2 R ddet d e Ble oo du tee Nod a RAA nd 8 Figure 6 Rudder Torque Motor eere 8 2 T 3 EhrOBCe o e le ano 9 Figure ZE Inroules avn summaa da oo 9 2 Consoles idees O 9 Figure 8 Left Console Cardiel 9 2210 DCK COMPU e 10 Figure 9 Stick Computer aad Bak AAA TAE ad bo node 10 A O E 11 Froure ODESSA Os 11 2 1 7 Trace Card usina 11 Fig re TES E AMA d used dei Loris apad iade 11 22 Computer Hard ware ier e eet ii 13 Figure 12 Instructor Operating Station IOS 13 2 3 Computer Software isset Re POP iaa 14 2 3 1 Simulink and Real Time Work shop eee 14 A E T O S 15 23 0 OE E Det T 15 2 3 4 TEP AP UDP ninas jas 15 PARE EAM SR 16 223 0 DEACAJD Chafibel zasadit tta e oes a Rie sr an e RA 17 2E malos DU o es 19 Figure 13 Analog Output Schematic eese 19 2 4 1 Stick and Rudder Ma N s 20 2 4 2 Instrument and Console Signals sees 20 Fioured d de DE S da tute ae eo a 20 Figure 15 Instrument Connections lt 20 Z Sal OUEDUE d eios RO 21 2 5 L Eront Cockpit VISUA S dete nt 21 Figure 16 Front Cockpit Visuals ii 21 vi Figure 17 Front C
9. ALL RIGHTS RESERVED REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 rab 5 11 00 Creation of code and Simulink Model This C file S function simulates the engine model based on the current throttle position as well as the current state that the engine is in This engine model allows four different types of engines to be modeled 1 Propeller piston engine 2 Turboprop 3 Hi Bypass 4 Turbojet with Afterburner or without The thrust based on altitude fuel flow nozzle position RPM and engine temp are calculated Inputs RFuelCap LFuelCap dd EngType i Np Prop Efficiency RThrottle 60 LThrottle Tsl lbs TSFCSINAB non Afterburning TSFC Sea Level TSFCSIAB Afterburning TSFC Sea Level rho a acoustic speed at altitude Vtrue knots Outputs RFuelFlo lbs of fuel hr LFuelFlo lbs of fuelhr RThrust lbf LThrust Ibf RNoz LNoz RRPM LRPM RTemp 0C LTemp 0C Cal Poly San Luis Obispo San Luis Obispo CA See simulink src sfuntmpl doc 61 Also see Pheagle_ HTML Copyright c 1990 1998 by The MathWorks Inc All Rights Reserved Revision 1 3 Define the S Function Name the same as in Simulink model define S FUNCTION NAME engine mod Define the S Function Level to be 2 for Models define S FUNCTION LEVEL 2 This header file is necessary for Simulink data structure It is highly suggeste
10. Control Mc Graw Hill 1998 Biezad Flight Control Systems California Polytechnic State University San Luis Obispo 1999 Jeppesen Private Pilot Manual 1997 Nise Control Systems Engineering Addison Wesley 1995 46 Appendix A 1 PhEagle Virtual Library Pheagle Virtual Library Simulation The Pheagle Flight Simulator A description of the Pheagle Flight Simulation How to run the simulation and a basic overview of what it does Simulation Models Stick Model Retrieves the Stick Rudder and Throttle inputs and converts the Analog signals to digital Instrument Model Receives the digital values for the instruments then convert the digital values to an analog signal that drives the instruments SixDOF Model Receives the Forces Moments and control inputs generated by the aircraft and computes the aircraft s position and orientation Standard Atmosphere Model Receives the Altitude then computes the density pressure temperature and speed of sound Engine Model Receives the throttle inputs and calculates thrust as well as engine temperature pressure and nozzle position Tutorials Times Two Tutorial Introduces User to Matlab s S Function and demonstrates how to link simulink models with C source code Model multiplies input by 2 and returns it s value Speed of Sound Tutorial Similiar to the Times Two tutorial except now user learns to handle several inputs and outputs The model reads
11. In general the cab sends stick and rudder inputs to the stick computer and throttle inputs are sent to Siblinc The signal then gets mapped to A D cards located in Spiegel through the trace card Spiegel then computes the equations of motion to generate the states of the aircraft The position and orientation is sent to each of the three visual computers Eagle Phantom and Pheagle which display the center left Phantom au Left View Spiegel piege Eagle 5 Center View Pheagle P Right View Computer Stick amp Rudder Forces Figure 2 Simulation Flow Schematic and right views respectively Spiegel also sends out analog signals to the cab Instrument settings and lights are sent through Spiegel to Siblinc then to the cockpit Stick and Rudder forces are sent to the stick computer and then to the stick and rudder to generate force feed back Each of these sections will be broken down to give a more detailed description of the signal flow 2 1 Analog Input The incoming analog signal to Spiegel reads the signals from the stick rudder and throttle and the left and right console panels Figure 3 shows a schematic of the analog input from the stick rudder throttle and consoles to the O computer Spiegel Stick Rudder Bottom Torque I Motor Assembly Cockpit Junction Box CJB Rudder Throttle Card Throttles Em I Left Console Card Left Console J Connectors Right Console Si
12. Stick Model Diagram Source Code ph stick cC file written in S Function format that reads the analog signals from the stick rudder and throttle then converts that signal to digital stick mdlSimulink block diagram that graphically displays the pilot s input and the produced output in terms of nominal percentage 50 Instrument Model This page describes the instrument model and how it works Below is the Instrument Model Diagram Source Code alinst cC file written in S Function format that receives the digital inputs from the simulation then converts the value to an Analog signal to drive the instruments stick mdlSimulink block diagram that graphically displays the instrument output for each of the instruments based on the digital input 51 SixDOF Model This page describes the SixDOF model and how it works The SixDOF Model treats the aircraft like a point mass It converts the Forces and Moments and Control Inputs generated by the aircraft to compute the aircraft s position and orientation The term 6 Degress of Freedom refers to the aircrafts translational and rotational positions x y z and Psi Theta Phi Source Code sixdofl c C file written in S Function format that computes the SIXDOF position SIXDOF mdl Simulink block diagram that graphically displays the inputs and outputs to the C code navion tsf A standard data file SAD file that contains the aircraft stability derivitives 52 Standard Atmosphe
13. Vtrue 1 69 a Tsl rho rhosl Tsl lbs if NumEng 1 RThrust 0 5 RThrottle Thrust LThrust 0 5 LThrottle Thrust printf RThrust3 1 i n RThrust printf LThrust3 1 i n LThrust else RThrust RThrottle Thrust LThrust LThrottle Thrust printf RThrust3 2 i n RThrust printf LThrust3 2 i n LThrust Non Afterburning Jet Engine Engine Type 4 if EngType 4 Thrust Tsl rho rhosl Tsl lbs if NumEng 1 RThrust 0 5 RThrottle Thrust 70 LThrust 0 5 LThrottle Thrust fprintf R Thrust4 1 i n R Thrust printf LThrust4 1 i n LThrust else RThrust RThrottle Thrust LThrust LThrottle Thrust printf RThrust4 2 i n RThrust printf LThrust4 2 i n LThrust j Afterburning Jet Engine Engine Type 5 if EngType 5 Thrust Tsl rho rhosl 1 0 7 Vtrue 1 69 a Tsl Ibs if NumEng 1 RThrust 0 5 RThrottle Thrust LThrust 0 5 LThrottle Thrust printf RThrust5 1 i n RThrust printf LThrust5 1 i n LThrust else RThrust RThrottle Thrust 71 LThrust LThrottle Thrust printf RThrust5 2 i n RThrust printf LThrust5 2 i n LThrust End Thrust Calculation Calculate fuel flow if EngType 5 Afterburning engine if RThrottle gt 0 65 Afterburner engaged TSFC TSFCsIAB a asl FuelFlow TSFC RThrust RFuelFlo FuelFlow else TSFC TSFCsINAB a asl FuelFlow
14. a HUD Copying the baseline simulation from the front cockpit to the rear cockpit will bring forth the development of a combat simulator Since the back seat is entirely digital copying the back seat and adding a desktop simulator will finally develop a Combat Simulation Arena where any number and any type of aircraft can be modeled within the same 3 Dimensional world Also now that the simulation is complete the simulator can be implemented into the classrooms to teach the students information about the cockpit 43 and visually see how an aircraft performs Most importantly the simulator will lead to the complete design of flight control systems for the non linear world Teamwork is the key A simulator is extremely hard to handle by yourself As the simulation grows and becomes more complex the workload will need to be split off in teams This will cause the simulator to grow exponentially and Cal Poly s strength in flight simulation as well 44 References 10 11 12 13 Almond Munger and Van Duren Introduction to PhEagle Flight Simulator California Polytechnic State University San Luis Obispo 1997 Gan Ricky PhEagle Flight Simulator Computer and Interface Connections California Polytechnic State University San Luis Obispo 1997 MATLAB Application Program Interface Guide The Math Works Inc 1997 SIMULINK Real Time Workshop The Math Works Inc User s Guide 1997 Hiranaka Douglas An Integ
15. and the Stick Computer The 5 volt signal gets modified for the analog target within the cab Figure 13 shows the analog output schematic Stick Rudder Motors Bottom Torque Motor Assembly Cockpit Junction Box CJB Right amp Left Console Cards A a Instruments IMP So Siblinc Instrument Motherboard Figure 13 Analog Output Schematic 18 2 4 1 Stick and Rudder Signals The stick and rudder can receive stick force commands from the simulation based on the amount of g s being generated by the aircraft maneuvers This force is sent to the stick computer which sends the signal to the stick and rudder torque motors to generate the force These forces can generate up to 50 pounds of force 2 4 2 Instrument and Console Signals From Siblinc several connectors split the signal from Siblinc to the instruments and consoles Initially the signal gets sent to the cockpit junction box CJB where it then gets sent to the instrument panel motherboard assembly Two connectors attach the signals to the motherboard these are known as IJ1 amp 132 Figurel4 shows these connectors mounted to the motherboard The signal finally reaches its destination target by a connection Figure 14 IJ1 amp IJ2 to one of the instruments from the motherboard Figure 15 shows the back of the instruments with their connections linking them to the motherboard assembly A tag on each instrument describes the channel num
16. back log SOCKET tcp send setup char host name char port 103 B 6 Slave c po ok ok ok ok aj aj aj aj a k ls ls ls ds ls o oe oe o k k kk k k k k k kk k k K k k k k k k K ok ok ok ok ok sk sk K 2K k k k MODULE slave c AUTHOR S Robert A Barger Jon Tonkyro DATE May 20 2000 Copyright c ALL RIGHTS RESERVED REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 JT amp RAB 5 20 00 Creation amp Tested Description Communications software for opening a UDP connection T between the master process running equations of motion Spiegel and a slave process running graphics Phantom Eagle and Pheagle x Additional command line arguments can be implemented to porduce cloud layer effects change database etc alkaa fe he A ohe ohe ohe ohe ohe ohe ohe ode ode ode ohe ohe ohe ohe ohe oko oko oko oko oko oko oko ok ok ok aj aj ok k k ls ds ls ds ds ls le le le o e o e k ohe ohe ohe ohe ohe ohe ohe ohe ohe k ohe ok ok ohe ok ok k kK k finclude lt g sys h gt finclude lt g consts h gt 104 include lt gv h gt include lt gvu_isg h gt include lt tmfbf h gt include modhostdata h External host control data include slave h Slave side stuff define SERVER 129 65 180 41 Spiegel s IP Address define Service_Port 5001 Pipe Line Port define BUFSIZE 56 Size of the struct we re sending define NUM_VEHICLES 2 Global struct Host data host
17. data Data from the master Global through this module only static GV Obi vobi NUM VEHICLESI static struct sockaddr in remote static char buf static int bufsize static int len 0 static SOCKET socket num 105 pol ok ok ok ok aj aj aj o a ls ls ds ls ls ls o oe oe o k o e ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe oko ok ok ok ok ok k ok aj aj k k k k k path init ES Dummy module not needed by slave lk fe he he he ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ode ohe ohe ohe ohe ohe oko oko oko oko oko oko oko ok ok ok ok ok ok k k k k fe fe fe k k k k o e o e k ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ok ok ohe ok LL void path init void ERROR SE SE ohe GE 2 oko oko oko oko oko oko oko ok ok ok ok ok ok aj a oe ls ls ds ds ds ls le oe oe o o k k ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe oko oko ok ok ok ok ok ok ok sk aj k K k k k eom init Dummy module not needed by slave NOA int eom init GV Geometry geoset GV Obi inst GV Obi terrain G Position pos init G Rotation rot init float speed init void geoset void inst void terrain void pos init void rot init void speed init return G FAILURE 106 j FEE SERE GE GE EE oko oko oko oko oko oko ok ok ok ok aj aj k k oe ls ls ls ls ls oe o oe k o k k k K ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe 2 K k K K k k K be K sk aj al K k k K slave init S Initial
18. of the input and output arrays The sample time section determines the time differential for the simulation The output section computes the output variables The termination section allows conditions to be set to terminate the simulation Various other sections can be added to make the code behave how and when the programmer wants it to 2 3 3 C Code The C Code for the simulation is written in the S Function format If the code is in the correct format the compiler will generate a dynamic linked library dll This is compiled C Code much like an executable Simulink searches for this dll based on the S Function name that was assigned to it To generate the dll the compiler must be set up correctly so Matlab knows where to find it The code cannot be written in C 1t must only be written in C The entire code for the simulation was written by students 15 2 3 4 TCP IP UDP Since the computers are networked together code had to be written to communicate between the two The goal was to have the O computer Spiegel compute the aircraft s position and orientation and send that information to the other three visual computers to generate the graphics A sample program was written in C for a UNIX platform to test the functionality of sending information across the Internet One side of the program acted as the server and the other program played the client This program then had to be modified to work under Windows using winsockets O
19. orientation and state which are sent to the two analog computers as well as the three visual computers Each of the four digital computers contains a network card and can communicate through a network hub which creates a Local Area Network LAN or Intranet The VO computer acts as a server and sends the aircraft s position orientation and state to each of the visual computers which act as clients Each visual computer is equipped with an Obsidian 2 Quantum 3D graphics card which is basically a modified 3Dfx Voodoo 2 card Each of these cards is set to run the glide hardware Additional hardware is sound cards located within Eagle and Pheagle and additional data acquisition cards in Phantom 13 2 3 Computer Software The four computers each run Windows 95 as their operating system This allows any windows applications to be implemented in the simulation Older simulation laboratories use VAX or VMS machines to run the simulation With the advent of faster low cost PC s the Windows platform allows students to work in a familiar environment This also allows the portability of adding new software to the simulation Currently the computers are equipped with MATLAB Simulink and the Real Time Workshop to run the simulation These computers use Visual C 6 0 to compile the simulation code and the visual software is generated using OpenGVS 2 3 1 Simulink and the Real Time Workshop The PhEagle simulation runs in Simulink by MATLA
20. various vectors a static void mdlInitializeSizes SimStruct S ssSetNumSFcnParams S 0 if ssGetNumSFcnParams S ssGetSFcnParamsCount S return Parameter mismatch will be reported by Simulink This section sets up the number of inputs if ssSetNumInputPorts S 1 return ssSetInputPortWidth S 0 10 10 is the number of inputs ssSetInputPortDirectFeedThrough S 0 1 if ssSetNumOutputPorts S 1 return ssSetOutputPortWidth S 0 3 3 is the number of outputs ssSetNumSampleTimes S 1 Take care when specifying exception free code see sfuntmpl doc ssSetOptions S SS OPTION EXCEPTION FREE CODE 87 Function mdllnitializeSampleTimes Abstract Specifiy that we inherit our sample time from the driving block W static void mdllnitializeSampleTimes SimStruct S ssSetSampleTime S 0 INHERITED SAMPLE TIME ssSetOffsetTime S 0 0 0 define MDL START fif defined MDL START Function mdlstart Initialize the state variables static void mdlStart SimStruct S This is where you add code for the first time the simulation starts For this simple file there is no need for any code in this section endif MDL START 88 Function mdlOutputs Abstract This section assigns the input variables to pointers in the u array and assigns the outputs to the y array
21. 1 Instrument Calibration Checklist 4 7 2 Throttle Calibration In order to develop an engine model simulation the throttles needed to be calibrated This reguired the code to be modified as well as adjusting the potentiometers on Siblinc The goal was to have the throttles read the same output at the same location This is crucial since any error results in the loss or gain of thrust Since the throttles are based on a percentage an error of 2 on a 10 000 pound engine results in a thrust error of 200 pounds This is sufficient and can cause the model to be inaccurate 36 Figure 34 shows the initial readings of the throttle The figure shows that the left throttle is extremely inaccurate but the right throttle s output is quite decent The left throttle reaches its maximums and minimum values too soon Also the slope of the output versus the position is too steep The SCALE will be modified to expand the left throttle s range as well as its slope Initial Throttle Settings Throttle o al e R Throttle Fwd a L Throttle Fwd 4 R Throttle Re 0 3 x L Throttle Rev 0 2 0 1 0 0 1 2 3 4 5 6 7 X pos Figure 34 Initial Throttle Readings Besides the digital output the analog output would also need to be analyzed Figure 35 shows the voltage output of the throttles Notice that both the throttles cross the zero
22. 28 4 Simulation Development The prior sections described how the PhEagle Simulator signals flowed and how to run and maintain the simulator as well as the lab The next section describes the potential of Cal Poly s PhEagle Flight Simulator 4 1 Graphics The main emphasis of this thesis was to generate graphics for the simulator Determining the accuracy of the aircraft model would be harder without graphics Although the aircraft model is linear the non linear SixDOF model did an excellent p i Figure 27 Pilot Verification job mimicking the flight characteristics of the actual aircraft Responses such as short period and phugoid oscillations as well as dutch roll movements were evident in the model These oscillations would occur in the actual aircraft as well Responses to the control inputs were correct High gain control inputs would generate a Pilot Induced Oscillation PIO that would cause loss of the aircraft Several pilots flew in the simulator and agreed that the aircraft model behaved like an actual aircraft such as the pilot in Figure 27 Overall the graphics proved that the model is correct 29 4 1 1 Terrain Database Further development of the graphics lead to the ease of the capability of OpenGVS Different terrain models could be chosen to allow the pilot to fly in a Korean database shown in Figure 28 filled with mountains or a Monterey Database equipped with an airport shown in Figure 29 Additional ter
23. B If the simulation was left entirely as code the programmer would be lost not knowing which variables were being sent which variable names are being used and the file order Simulink allows this process to become simple Simulink allows the students to visually map the variables as the simulation computes them Simulink also allows the users to easily grab a variable and monitor it or link it to a subsystem within the simulation Variable names don t have to match for the code to run The file order is easy to see as the programmer can follow the flow of the simulation and visually see the order that files get called within the simulation The Real Time Workshop allows the simulation time differential to be changed i This allows a more accurate integration to keep the simulation running in real time This 14 also allows the entire simulation to be compiled into one executable Programs can be generated distributed then tested in the classrooms or students can use them at home 2 3 2 S Functions The Real Time Workshop in conjunction with Simulink requires the code to be written in a special S Function format This allows different sections of the code to be run at different times during the simulation For instance the S Function requires the code to have a start initialize sample time output and termination sections The start section is only called the first time the simulation runs The initialize section initializes the size
24. Development of an Instrument Landing Simulation for Cal Poly s Flight Simulator using MATLA B Simulink Presented to The Faculty and Representatives of California Polytechnic State University San Luis Obispo Aerospace Engineering Department In Fulfillment of Master of Science in Aerospace Engineering Submitted by Robert A Barger 6 7 00 Authorization Page I grant permission for the republication of this thesis in its entity or any of its parts without any further authorization by me Signature Date Approval Page TITLE Development of an Instrument Landing Simulation for Cal Poly s Flight Simulator using MATLA B Simulink AUTHOR Robert A Barger DATE Friday May 26 2000 Dr Daniel J Biezad Advisor Signature Dr Jin Tso Committee Member Signature Dr Jordi Puig Suari Committee Member Signature Edward Burnett Committee Member Signature Abstract Most people learn by seeing hearing or feeling Of these senses the one that generates the most productive learning is visual stimulation Engineering students spend most of their time calculating values for theoretical variables but never see them applied Cal Poly s Flight Simulation Laboratory enables students to visualize these variables and see them in action through cockpit instruments and 3 Dimensional visuals The primary purpose of this thesis is to develop a simulation laboratory that can be inte
25. Model instruments 3 2 2 Tutorials Tutorials allow students to learn certain skills required to run the simulator Students learn how to generate code models and more within the tutorials Each time a student creates something new the student will create a tutorial so others will learn the same For instance if a student learns how to create a GUI the student will create a GUI tutorial so others will learn as well 27 3 2 2 1 Times Two Tutorial This is a simple tutorial that teaches the students how to compile code in Matlab Although this is a simple model since 1t computes the input by two the code is quite complex To do this simple model will require two pages of code 3 2 2 2 Speed of Sound Tutorial This is a more complex tutorial where the student has to create the code and model from scratch Students here learn the basic S Function format The model receives the gamma gas constant temperature and velocity and computes the speed of sound and Mach number 3 2 3 Documentation Any documentation written for the simulator or that pertains to the simulator is to be stored in the documentation directory This primarily includes student work such as theses senior projects class or project work etc Additional documentation are helpful references that pertain to the simulator development such as military standards FAA guidelines software documentation that pertains to Matlab Simulink OpenGVS TCP IP UDP etc
26. S Function mdlDerivatives i static void mdlDerivatives SimStruct S endif MDL_DERIVATIVES Function mdlTerminate Abstract No termination needed but we are required to have this routine U static void mdlTerminate SimStruct S 82 ifdef MATLAB MEX FILE Is this file being compiled as a MEX file include simulink c MEX file interface mechanism else Hinclude cg sfun h Code generation registration function Hendif 83 B 3 ILS_Model c S function ils model MODULE ils model c AUTHOR S Robert A Barger Edwin Casco Paul Patangui DATE May 18 2000 Copyright c ALL RIGHTS RESERVED REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 rab 5 18 00 Creation of code and Simulink Model This C file S function simulates an ILS beacon located at the end of the runway The required inputs are the aircraft s position as well as the airport s location and runway heading The CDI and CD Vert are the angles off the runway centerline They are the same angle just at different scales The CdHor angle is the approach glide slope angle n order to be on Glideslope this angle must be 2 5 degrees nputs T ACX Aircraft X position ft ACY Aircraft Y position ft ACZ Aircraft Z position ft ACU Aircraft U ft 84 ACV Aircraf
27. SFcnParamsCount S return Parameter mismatch will be reported by Simulink hs section sets up the number of inputs if ssSetNumInputPorts S 1 return ssSetInputPortWidth S 0 2 4 is the number of inputs ssSetInputPortDirectFeedThrough S 0 1 if ssSetNumOutputPorts S 1 return ssSetOutputPortWidth S 0 4 2 Number of outputs Stick rudder and throttles ssSetNumSampleTimes S 1 Take care when specifying exception free code see sfuntmpl doc ssSetOptions S SS OPTION EXCEPTION FREE CODE Function mdlInitializeSampleTimes 78 Abstract Specifiy that we inherit our sample time from the driving block 9 static void mdlInitializeSampleTimes SimStruct S ssSetSampleTime S 0 INHERITED SAMPLE TIME ssSetOffsetTime S 0 0 0 define MDL START Change to undef to remove function fif defined MDL START Function mdlStart Abstract nitialize the da cards static void mdlStart SimStruct S endif MDL_START define MDL INITIALIZE CONDITIONS Change to undef to remove function if defined MDL INITIALIZE CONDITIONS Function mdlInitializeConditions o o cre rete Abstract 79 Initialize the state Note that if this S function is placed within an enabled subsystem which is configured to reset states this routine will be called during the rese
28. TSFC RThrust RFuelFlo FuelFlow if LThrottle gt 0 65 Afterburner engaged TSFC TSFCsIAB a asl FuelFlow TSFC LThrust LFuelFlo FuelFlow else 72 TSFC TSFCsINAB a asl FuelFlow TSFC LThrust LFuelFlo FuelFlow non afterburning engine else TSFC TSFCsINAB a asl FuelFlow TSFC RThrust RFuelFlo FuelFlow TSFC TSFCsINAB a asl FuelFlow TSFC LThrust LFuelFlo FuelFlow end TSFC calc Calculate the Right Engine RPM RRPM RThrottle 100 Calculate the Left Engine RPM LRPM LThrottle 100 Calculate the Right Engine Nozzle Position RNozzRThrottle 100 73 Calculate the Left Engine Nozzle Position LNoz LThrottle 100 Calculate the Right Engine Temp RTemp RThrottle 1400 Calculate the Left Engine Temp LTemp LThrottle 1400 return end calculate Function mdlTerminate Abstract No termination needed but we are required to have this routine static void mdlTerminate SimStruct S ifdef MATLAB MEX FILE Is this file being compiled as a MEX file include simulink c MEX file interface mechanism else 74 Finclude cg sfun h Code generation registration function Hendif 75 B 2 Spool c FREE RE SE GE 2 2 2 2 ol ok ok ok ok aj aj aj o a a ls ls ls ds ls oe oe oe oe o k k k k k k k kk k k k k k k k k k kk k
29. The deviation angles are a calculated in the Calculate function Inputs T ACX uPtrs 0 x ACY uPtrs 1 E ACZ uPtrs 2 ACU uPtrs 3 a ACV uPtrs 4 ACW uPtrs 5 APX uPtrs 6 APY uPtrs 7 APZ uPtrs 8 APpsi uPtrs 9 Outputs T yl0 CDI y 1 CDVert iS y 2 CDHor el static void mdlOutputs SimStruct S int_T tid 89 InputRealPtrsType uPtrs ssGetInputPortRealSignalPtrs S 0 real_T y ssGetOutputPortRealSignal S 0 Read in the Inputs ACX uPtrs 0 ACY uPtrs 1 ACZ uPtrs 2 ACU uPtrs 3 ACV uPtrs 4 ACW uPtrs 5 APX uPtrs 6 APY uPtrs 7 APZ uPtrs 8 APpsi uPtrs 9 Calculate the Deviation Angles Calculate Assign the Outputs yl0 CDI y 1 CDVert y 2 CDHor 90 void Calculate const double GlideSlope 2 5 Define the Glide Slope Angle const float pi 3 14159 double Thetal 0 Angle from Horizontal double Theta2 0 Supplement of Thetal double Theta3 0 From Horizontal to runway centerline double Theta4 0 Angle from Horizontal to airport double x 0 X distance between aircraft and airport double y 0 Y distance between aircraft and airport double z 0 Z distance between aircraft and airport double a 0 Arc Length of CDVert double r 0 Radial distance from airport to aircraft double lambda 0 Calculate Theta for CDI and CDVert x ACX APX y ACY APY z ACZ APZ
30. ach number and displays them in the Simulink window To do this you will need to develop a subsystem see Mach md l A subsystem is necessary whenever there are multiple inputs and outputs or when you are developing a model This allows the entire simulation diagram to become less cluttered and easier to follow The subsystem icon can be found in the Simulink library under connections Basically when you doubleclick on a subsystem it gives you a new Simulink window An S Function that has multiple outputs and inputs needs a Multiplexer MUX and DeMultiplexer DEMUX The MUX and DEMUX icons can be found in the simulink library under connections This basically allows the input and output to be in array form Each of the inputs and outputs must be assigned to a port You can specify the number of ports by right clicking on the MUX and DEMUX and selecting parameters The input and output ports can be found in the connections toolbox as well Once we have the model set up we need to develop the S Function This time instead of copying the code directly you re going to write each line of the code and achieve a simple understanding of the S Function format Look at speed sound c This file is a little cleaner in comparison to timestwo c but is still of the same form Go over the code and look at the comments The comments show you where variables are declared where the number of inputs and outputs are determined where the inputs and output arrays are fill
31. ack of cabinet of the instructor operating station This card allows each channel to be split up into either an input or and output If the signal is an input signal it goes to one of the A D PC lab cards If the signal is Figure 11 Trace Card JI an output it is sent from either the 16 bit D A card or the 12 bit D A card The trace card receives three connectors from Siblinc An additional connector is also sent from Siblinc however the channels within this connector are not known To add these channels to the simulation another trace card would need to be added as well as some additional A D and D A cards Luckily additional cards are located within the hardware cabinet 12 2 2 Computer Hardware The computers integrated into the simulation are four Pentium 166 computers Figure 12 shows the Instructor Operating Station IOS where each computer is mounted within the cabinet Each computer serves a distinct purpose This allows the simulation to be run in real time since each computer is designated for a specific task The I O Computer contains four data acquisition cards a 16 and a 12 bit Figure 12 Instructor Digital to Analog D A card a 12 bit Analog to Operating Station IOS Digital A D card and a 48 bit digital input output card The I O computer handles the analog inputs and outputs to the simulation as well as computing the Equations Of Motion EOM to solve for the aircraft s position
32. arameter mismatch will be reported by Simulink if ssSetNumInputPorts S 1 return ssSetInputPortWidth S 0 6 x y Z psi theta phi ssSetInputPortDirectFeedThrough S 0 1 96 if ssSetNumOutputPorts S 0 return ssSetOutputPortWidth S 0 1 no outputs ssSetNumSampleTimes S 1 Take care when specifying exception free code see sfuntmpl doc ssSetOptions S SS OPTION EXCEPTION FREE CODE len sizeof struct sockaddr in Function mdllnitializeSampleTimes Abstract Specifiy that we inherit our sample time from the driving block static void mdlInitializeSampleTimes SimStruct S ssSetSampleTime S 0 INHERITED_SAMPLE_TIME ssSetOffsetTime S 0 0 0 97 define MDL START fif defined MDL START Function mdlstart A static void mdlStart SimStruct S int temp setup winsock WSADATA info WSAStartup MA KEWORD 1 1 amp info create the server socket server socket tep recv setup wait for the client to say something get his address temp recvfrom server_socket buf sizeof buf 0 struct sockaddr amp you 4 len printf received hello from center client n endif MDL_START Function mdlOutputs 98 static void mdlOutputs SimStruct S int_T tid int n InputRealPtrsType uPtrs ssGetInputPortRealSignalPtrs S 0
33. ber of the instrument This is the same channel as on Siblinc Figure 15 Instrument Connections 19 This channel also is etched into the motherboard The Model II Cockpit Book IV describes the electrical connections in detail with schematics and tables for each wiring connection 2 5 Visual Output The visual output is split up into two sections the front cockpit visuals and the rear cockpit visuals Each displays the pilot s visuals and the Instructor Operating Station IOS visuals 2 5 1 Front Cockpit Visuals The Spiegel computer also sends information about the aircraft to the visual computers Figure 16 shows the front cockpit visuals The visuals are setup to generate three views Eagle is designated as the center visual computer Eagle will display the center view as well as the HUD Phantom and Pheagle will display the left and right views respectively Figure 16 Front Cockpit Visuals The visuals can be either a Monterey database with an airport or a Korean database with mountains The pilot and the IOS have a set of visuals Figure 17 shows the IOS visuals The IOS visuals are the same as the pilot s visuals This allows the operator to see where the aircraft is flying and still be able to monitor the state of the aircraft within the Simulink simulation window Also the operator can generate charts in real time or use any other 20 tools that Simulink has to offer without stopping the simulation This allows
34. blinc Card Right Console n Figure 3 Analog Input Schematic The analog inputs are broken down into control inputs or switches Control inputs include the stick rudder and throttle inputs Switches include any of the switches located on the consoles the stick or the throttle The stick and rudder inputs send signals to both the Siblinc and the Stick Computer The throttle is located on the left console and is connected to the left console card Both console cards connect to the Cockpit Junction Box CJB located beneath the simulator Any signals connected to the CJB get sent to Siblinc Control inputs send voltage signals to Siblinc and or the Stick Computer based on the control device These inputs then get scaled to a range of 5 volts This voltage is then sent to the trace card where the signals are broken down to the desired pin arrangement for the corresponding A D card located within Spiegel 2 1 1 Stick Stick inputs can be the stick position velocity and stick trim settings as well as the buttons located on the stick such as the trigger and the hat switch Originally the simulator cab was an F 4 Phantom simulator The stick is an F 15 Eagle stick shown in Figure 4 which was pe added to the simulator for handling qualities research at NASA Dryden Hence with the Figure 4 F 15 Stick combination of the two the simulator received its name PhEagle The stick is connected to the stick torque moto
35. d to look at this file to see the structure of the S Function Hinclude simstruc h Include any C header files or other files needed for syntax or class definition include lt stdio h gt Hinclude lt math h gt Declare local input and output varaible names Inputs float RFuelCap LFuelCap Np RThrottle LThrottle Tsl 62 float TSFCsINAB TSFCsIAB rho a Vtrue int EngType NumEng Outputs float RFuelFlo LFuelFlo RThrust LThrust RRPM LRPM RNoz LNoz RTemp LTemp void Calculate Function mdlInitializeSizes Abstract Setup sizes of the various vectors static void mdlInitializeSizes SimStruct S ssSetNumSFcnParams S 0 if ssGetNumSFcnParams S ssGetSFcnParamsCount S return Parameter mismatch will be reported by Simulink This section sets up the number of inputs if ssSetNumInputPorts S 1 return 63 ssSetInputPortWidth S 0 13 12 is the number of inputs ssSetInputPortDirectFeedThrough S 0 1 if ssSetNumOutputPorts S 1 return ssSetOutputPortWidth S 0 10 10 is the number of outputs ssSetNumSampleTimes S 1 Take care when specifying exception free code see sfuntmpl doc ssSetOptions S SS OPTION EXCEPTION FREE CODE Function mdllnitializeSampleTimes Abstract Specifiy that we inherit our sample time from the driving block
36. data collection to be much easier and more robust Operators can send commands to the pilot to get the data that they want The IOS visuals also serve as a desktop simulator so operators can fly and monitor the simulation by Figure 17 Front Cockpit IOS themselves This allows the operator to perform run time debugging without the help of others 2 5 1 Rear Cockpit Visuals The rear cockpit simulation is similar to the front cockpit except that a single machine runs the back seat The computer calculates the equations of motion and displays the graphics The rear cockpit is entirely separate from the front cockpit except for Figure 18 Rear Cockpit Visuals an Ethernet link Figure 18 shows the back seat visual setup A 15 inch flat screen monitor is mounted in the back seat since a regular monitor would not fit Similar to the front cockpit the rear cockpit has an IOS This serves the same purpose as the front seat Figure 19 Shows the IOS visuals for the rear cockpit The increased visuals of all stations allow two pilots and two or more operators to monitor the aircraft s states and the pilot s maneuvers Figure 19 Rear Cockpit IOS 21 3 Simulation Operations Procedures The hardest task for students working on this simulator is trying to understand how 1t works Due to its initial development there are little resources that explain how the simulator works In order for the learning curve to decrease adequate
37. documentation and resources need to be made available for the next student working on this project The PhEagle Operations Manual and the PhEagle Virtual Library contain descriptions and procedures of how to run the simulator where to store back up files model descriptions tutorials and documentation Each student working on the simulator will update the PhEagle Operations Manual and the PhEagle Virtual Library 3 1 PhEagle Operations Manual The PhEagle Operations Manual contains operations and procedures of how to run the simulator Also included are references of student work such as previous operation manuals student senior projects and theses Software hardware and API implementation are included such as Matlab GUI documentation TCP IP and UDP documentation A D and D A card information Most importantly the source code is printed out and located in its appropriate section describing the model 3 2 PhEagle Virtual Library The PhEagle Virtual Library is much like the PhEagle Operations Manual except that it is Web based This allows a tree structure library to store documentation code and any other pertinent information into subsequent directories Within the library is a 22 description of each model the corresponding code model file executable and documentation Also included are tutorials in HTML format This describes a step by step format on how to compile code generate models and repeat any process that has been
38. e models had to be generated calibrated and tested Once these were completed the graphics had to be implemented into the simulation complete with an airport and terrain database Once completed the simulation starts the aircraft at a distance from the airport where the pilot uses the instruments along with the visuals to land the aircraft at the airport 1 5 Continuing Research The next step is to integrate multiple aircraft into the simulation arena The simulator cab is a two seater which allows the addition of another cockpit The rear cockpit is entirely digital complete with a flat screen display a gaming joystick throttle and rudder pedals This will enable the simulator to have dog fighting capability Since the rear cockpit is entirely digital it can be copied to create another desktop simulator which can be added to the simulation to create a flight simulation arena 2 Simulation Flow The PhEagle Flight Simulator is quite complex due to the interaction between the digital and analog signals therefore it is important to understand the signal flow of the simulation This enables the operator to be able to trace a signal to see 1f it is getting to and from the simulator cab Figure 2 gives a simplified description of the input and output signals to and from the cab the analog computers and the digital computers The yellow arrows represent inputs to the I O computer Spiegel and the green arrows represent the outputs
39. e set individually to control the output of each engine If the aircraft has only one engine the thrust is divided in half by each engine setting The throttle generates an input of a nominal percentage from 0 to 1 Within the throttle region there are four stops OFF IDLE MIL and MAX OFF is at 0 thrust IDLE is at 10 MIL is at 62 and MAX is at 100 If the engine being modeled is a jet equipped with an afterburner the afterburner range is from MIL to MAX In order to engage the afterburners the grasps underneath the throttle must be pulled Additional buttons on the throttle are flap settings rudder trim and buttons and switches that could be used for speed brakes communication buttons etc All throttle inputs get fed to the left console card 2 1 4 Consoles The right and left console each have an independent card to read in the input such as pitch roll and yaw control augmentation switches stick force on off switches and more Currently the only console card integrated into the simulation is the left console card shown in Figure 8 There are additional cards for both the left and right console To receive inputs from the right console the right console card would have to be Figure 8 Left Console Card mounted and connected into the simulator 2 1 5 Stick Computer The stick computer controls the inputs and outputs to and from the stick and rudder motors The most important feature of the stick compu
40. ed and where the computation occurs Once you have finished writing the code repeat the process you did in tutorial 1 to generate the dll necessary for run time Other important files to look over to try to understand the S Function format are simstruc h simulink c and sfuntmpl doc 58 Source Code speed_sound cC file written in S Function format that reads in 4 inputs Gamma R Temp Velocity and computes 2 outputs Speed of Sound and Mach Number Mach mdlSimulink block diagram that graphically displays the user s input and the produced output This model is more complex then the XTwo model since a subsystem is required for multiple inputs and outputs simstruc hSimulink header file that describes the included file necessary for the S Function Good reference to see what functions could be added and the structure necessary for those functions Look at the comments and the structure simulink cAnother inprotant Simulink header file that describes another included file necessary for the MEX Function Good reference to see what is required for the MEX function Again look at the comments and the structure sfuntmpl docExcellent source of documentation for understanding the S Function format Notice that it is referred to in all the source code files 59 B 1 Engine_Mod c S function engine mod MODULE engine mod c AUTHOR S Robert A Barger Dieter Pestal Dan Salluce DATE May 11 2000 Copyright c
41. grated into the classrooms and enable the students to learn the simulation in the shortest time possible Not many schools have a flight simulator where students can design and build a simulation from beginning to end The Cal Poly Flight Simulation Laboratory has computers analog hardware a simulator cab software and state of the art visuals that create an entire set of tools which allow students to become complete flight simulation engineers The students learn the information that is being sent to the pilot which gives them a better understanding of the pilo s point of view Students not only learn the Aeronautical Engineering side of flight simulation developing the equations of motion but they also learn the Computer Science and Electrical Engineering side of simulation by integrating computers with analog hardware Future capabilities for the Cal Poly Flight Simulation Laboratory are endless Students can develop a simulation as detailed as possible as long as new simulations are added to the system and new hardware is upgraded to the lab Currently the laboratory has only one flight simulator but with the advent of new dynamic technology it is possible to add several simulators to develop a simulation arena iii Acknowledgements I would like to thank Doug Hiranaka and Fritz Anderson for their initial development of this project Fritz Anderson created the hardware integration of the simulator cab with the software code Doug H
42. input with the digital inputs from the joysticks However since the rear cockpit has no instruments a HUD must be generated to display the aircraft s states to the pilot 32 4 3 Heads Up Display OpenGVS already has a demo model that creates a Heads Up Display HUD Implementing this demo into the simulation will allow the aircraft s states to be displayed on the center view for both the front and rear cockpits The model already computes the states needed so all that needs to be done is to integrate the HUD into the simulation This can be done by sending a struct containing the aircraft states across the Ethernet to the center computer 4 4 Combat Simulator Combat simulators require at least two or more vehicles With the completion of the rear cockpit baseline with a HUD both simulations are ready for dog fighting Another model within OpenGVS uses a generic missile simulation that allows a missile to be fired when a key is pressed Implementing this model into the simulation will allow the simulation to be dog fight capable OpenGVS already has the demos set up to allow the number of vehicles to change Changing this variable to two allows the aircraft to fly within the same three dimensional world and see each other 4 5 Combat Simulation Arena A combat simulation arena is when more than two aircraft are fighting against each other in the same world Since the rear cockpit is entirely digital adding another deskto
43. iranaka developed the interface of the non linear six degree of freedom simulation using Matlab s Simulink I would like to also thank the following people for their help on the simulator during the past few years Aaron Munger s knowledge on the simulator s hardware aided in the development of the analog section of this thesis Jon Tonkyro provided expertise in networking and helped with the graphics Edwin Casco and Paul Patangui assisted in the development of an Instrument Landing System ILS Simulation Members from the Spring AERO 320 helped with the engine model simulation Jeff Nadel helped with the lab networking for the ATL building Dan Powell helped with moving the simulator and electrical assistance Dr Daniel J Biezad s continued efforts to make flight simulation and controls a strong emphasis at Cal Poly San Luis Obispo David Lowe and the F 18 and UH 1N simulation groups at Manned Flight Simulator gave me experience and insight on how flight simulators should be developed Finally I would like to thank Linda Jarrard for her support during the time I invested on this project Table of Contents 1 Introduction ouo itte ipie Eh teo tasto buie iier to tem Lise din idee assores daoo osrs oases 1 1 1 Computers and Hardware niei ierat Ie neo ped eo Cede co nena euius 1 1 2 SOLOW ALC id a One 1 13 PRE ase ATOBIVE samassa tao ra te dais 2 14 Research Ob CCI VOS i 3 Figure 1 Advanced Technologies Laboratories ATL 3 Pit SATO
44. ircraft time of day visibility etc Modification of the GUI could incorporate graphics such as graphs a display of the ownship s attitude with a 3 D model stick position etc Additional GUIs can be added to the simulation with the use of Microsoft Foundation Classes MFC which are useful in Windows applications 39 5 Simulator Implementation The most important purpose of the PhEagle Flight Simulator is to let the students become more familiar with the inside of the aircraft Most students get their flying experience by being a passenger PhEagle allows the students to sit in the cockpit fly the aircraft become familiar with what information is being sent to the pilot and learn the variables that they ve been studying perform in real time The simulator allows a direct use in the classroom particularly in the courses Stability amp Controls Aircraft Design Flight Control System Design Space Control System Design and especially Flight Simulation all offered at Cal Poly 5 1 Stability Derivatives Since the simulation only requires a SAD file any aircraft can be modeled as long as the stability derivatives are known Students in Stability amp Controls receive an introduction to stability derivatives The class can now visually see what happens when certain stability derivatives are changed and see their effect in real time Aircraft Design students can design their aircraft then compute the stability derivatives for
45. is routine 9 static void mdlTerminate SimStruct S ifdef MATLAB MEX FILE Is this file being compiled as a MEX file include simulink c MEX file interface mechanism else Hinclude cg sfun h Code generation registration function Hendif 101 B 5 Server h EE E GE GE GE o oko ok ok ok aj aj os a a k ls ls ls ds ls le le oe o k k kk k k k k k kk k k K k k k k k k K k k K ok ok sk aj K K k k k MODULE server h AUTHOR S Robert A Barger Jon Tonkyro DATE May 8 2000 Copyright c ALL RIGHTS RESERVED REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 JT 5 05 00 Creation into C Format amp Tested 1 RAB 5 08 00 Creation into S Function Format EEEE EEE ohe ohe ohe ohe ohe ohe ode ohe ode ohe ohe ohe ohe ohe oko oko oko oko oko oko a ok ok ok ok k aj k ls ls ds ds ls ds le le ls le le k kk ohe ohe ohe k k k k k k kK k k K k k K K typedef float G Gfloat Double precision typedef int G Boolean typedef struct G_Gfloat x G_Gfloat y G_Gfloat z G_Vector3 General 3D vector 102 Hdefine G_Position G_Vector3 define G Rotation G Vector3 struct Host data Continous data from host sent every frame G_Position ownpos Ownship vehicle position G Rotation ownrot Ownship vehicle rotation angles int guit 1 to QUIT now J SOCKET tcp recv setup SOCKET tcp listen int server socket int
46. ize the communications interface called once l by the slave to establish communications with the host NOTA int slave_init void int status G SUCCESS static char sktNameServer slave static char sktHostPeer NULL anybody GV Obi cursor GV Scene scene int temp float x 1 y 2 z 3 psi 4 theta 5 phi 6 WSADATA info if WSAStartup MAKEWORD 1 1 amp info SOCKET ERROR fprintf stdout slave get data error reading from socketin return G_FAILURE 107 create the socket socket num socket AF INET SOCK DGRAM 0 fprintf stdout created socket in socket num remote sin family AF INET remote sin addr s addr inet addr SERVER remote sin port Service Port 1f socket_num lt 0 exit 1 GV obi ing by name CURSOR amp cursor if cursor GV obi set state cursor G OFF GV chn inq scene channel 0 amp scene 1f scene int vehicle for vehicle 0 vehicle lt NUM_ VEHICLES vehicle By master slave conventions vehicles are named P1 P2 108 G_Name name sprintf name P d vehicle 1 GV_obi_instance_by_name name amp vobi vehicle GV sen add object scene vobi vehicle if vobi vehicle fprintf stdout slave init instanced vehicle named s n name fprintf stdout slave_init Sending hello to server n temp sendto socket_num hello 4 0 struct sockaddr amp rem
47. kk ok ok ok k k k k k K k MODULE spool c AUTHOR S Robert A Barger Michael Ortner Jeff Doll DATE September 25 1998 Copyright c ALL RIGHTS RESERVED Cal Poly San Luis Obispo 1998 REVISION HISTORY REV AUTHOR DATE DESCRIPTION 0 rab 5 11 oo Creation of code and Simulink Model S mex See simulink src sfuntmpl doc S mex Copyright c 1990 1998 by The MathWorks Inc All Rights Reserved Revision 1 3 This S function block Reads the commanded throttle position and determines whether the engines are spooling up or spooling down The program keeps track of the last position and if the difference is positive then the engine is spooling down else it is spooling up The spool up time delay was set to 0 5 sec and the spool down time delay was set to 0 25 sec NI IO define S FUNCTION NAME spool 76 define S FUNCTION LEVEL 2 Hinclude simstruc h ftinclude lt dos h gt include lt bios h gt include lt math h gt include lt stdlib h gt include lt string h gt include lt conio h gt include lt math h gt include lt stdio h gt double oldVals 2 double LThrottle RThrottle int LTauDN 0 int RTauDN 0 Function mdlInitializeSizes Abstract Setup sizes of the various vectors static void mdlInitializeSizes SimStruct S 77 ssSetNumSFcnParams S 0 if ssGetNumSFcnParams S ssGet
48. le however the code is not Look at the C File source code shown below timestwo c For a simple program that reads in one value multiplies that value by two then returns it becomes quite complex For now don t get too discouraged about figuring out the code The objective of this tutorial is to learn how to link simulink block diagrams with C Source code The next tutorial is to actually understand the code Steps When performing these steps don t just copy the model but actually draw the simulink diagrams Remember this is a tutorial for your own benefit 1 Create a directory for you to practice your tutorials in 2 Create a simulink block diagram similiar to xtwo mdl 3 Name the S Function Right click on the S function to get the parameters window NOTE Make sure the S Function has a different name then the simulink model 4 Copy the timestwo c to your tutorial directory Look over the code and become familiar with it s structure Find where the S Function is defined Make sure that this name is the same as the one that you used earlier in step 3 Find where the input is multiplied by two then returned 56 5 Create the dll dll s stand for dynamic linked libraries You ll find them everywhere on any computer Basically a dll links code to other files For our case we need to link the simulink diagram to the source code Here s how to create a dll 5a Open Matlab Go to directory in Step 1 NOTE Model and source code do n
49. librated to insure that all the instruments were displaying the correct information to the pilot However when the simulator was moved most of these instruments were no longer calibrated Also the throttle was not functioning In order to develop an engine model the throttles needed to be calibrated tested then entered into the simulation 4 7 1 Instrument Calibration In order to calibrate each instrument the output value was plotted versus the input 17 Tf the instrument s output matched the input for several values then it was determined to be calibrated The instrument was calibrated by either modifying the code or adjusting the potentiometers Once the instruments were calibrated they were tested in the simulation to see 1f their values were correct Table 1 shows a list of the instruments which passed calibration and those which still need work The Vertical Course Direction Deviation Indicator channel was proven to be faulty This was exchanged for the Internal Pressure instrument The vertical velocity s SCALE potentiometer was also broken making calibration impossible This will need to be fixed 35 Instrument Status Instrument Calibrated Further Research Broken faltimeter d dd 0 0 ll hiach beter aw CT o urpeedin emor g Total pressure ww oy po Directional le o Attack Sidaclip Inchcabor ne Faghi Engine Horzle 1 TIT A Left Engine Temp m Table
50. nce the program proved to work it had to be modified again to work using UDP UDP is similar to TCP except that it allows the communication to be connectionless Once the program was working the code had to be converted to C then added to a test bed simulation within Simulink The program was tested and it worked perfectly with little lag in the frame rate The final step was to have the test bed simulation work with the graphics since the communication barrier had been breached the next step was to have the model work with the graphics 2 3 5 OpenGVS OpenGVS offers excellent 3 D rendering scene software that is already set up for flight simulation OpenGVS already has imbedded functions that allow terrain databases camera views vehicles lighting etc to be simply added to the simulation Included within OpenGVS are demo programs that give a programmer an idea of how to create visuals The demos include a Heads Up Display HUD demo that has an aircraft fly through a database of Korea in a Mig 29 armed with missiles Other demos include a 16 tank demo with different helicopters and tanks within the same battlefield and a Monterey demo that starts the aircraft in final approach The demos also included a master slave program that would be perfect as a baseline for networking visuals The server code was created to send the aircraft s position and orientation The client code was modified to work as the slave within the OpenGVS environme
51. nd Phantom This module acts as a server Spiegel to the other 3 clients Slave exe must be run on the other 3 clients as well as their batch files The server sends a struct to the clients which can be modified to send more additional information Different 94 command line arguments can be added to Slave exe to run different terrain databases set the cloud layer etc NITO define S FUNCTION NAME server define S FUNCTION LEVEL 2 Hinclude simstruc h include lt dos h gt Hinclude lt math h gt ftinclude lt stdlib h gt include lt string h gt include lt conio h gt include lt stdio h gt for Winsockets include lt winsock2 h gt include server h define Service_Port 5001 define BUFFER_SIZE 56 declare variables 95 struct sockaddr_in you the outgoing socket struct SOCKET server_socket 0 socket descriptor for the server socket SOCKET client_socket 0 socket descriptor for the client socket int message_len 0 length of the received message struct Host_data host_data float x 1 y 2 z 3 psi 4 theta 5 phi 6 char buf BUFFER SIZE buffer for receiving from remote int len 0 Function mdllnitializeSizes o o oooooooooooooo Abstract Setup sizes of the various vectors A static void mdlInitializeSizes SimStruct S ssSetNumSFcnParams S 0 if ssGetNumSFcnParams S ssGetSFcnParamsCount S return P
52. nd analog hardware can be implemented in the simulation allowing further research into futuristic cockpit displays or imbedded avionics Due to the networking capability of the simulation simulators can be added as long as there is enough bandwidth Desktop simulators or other analog simulators can be added to the simulation to develop a simulation arena 1 2 Software The simulation integrates C code with Matlab s Simulink S Function Applied Programmer s Interface API Simulink s Graphical User Interface GUI allows the user to see the variables flow through the simulation At any time the user can monitor or graphically display one of the variables and plot it as a function of time This is far better than debugging in most common compilers since Simulink allows the programmer to see the variables in real time Simulink also allows the simulation to be broken down into subsystems and individual simulation models These models can be individually tested or added to a completely different simulation Simulink s S Function API allows any C Code to be integrated into the simulation This allows the implementation of other APP s into the simulation OpenGVS 1s another API that uses OpenGL code to generate a Realtime Scene Management for Three Dimensional Visuals OpenGVS has specific functions that enable the three dimensional environment to be changed such as camera position lighting and visibility 1 3 PhEagle Archive The simulation lab
53. ng a 25 second time delay on spool up and a 5 second time delay when spooling down Included is the work performed by the Spring 2000 Aero 320 class who developed the Engine Model Tested it Calibrated the Throttle as well as the Instruments Engine Model Simulation Below is the Engine Model Diagram Source Code Spring AERO 320 class Engine Model Simulation engine_mod cC file written in S Function format that receives the throttle inputs from the stick model then calculates the engine model variables engine mdlSimulink block diagram that graphically displays the engine model outputs based on throttle position Embedded is the spooling model spool cC file written in S Function format that computes the time delay for the throttles based on whether they are spooling up or spooling down spooltst mdlSimulink block diagram that graphically displays the spool model outputs based on throttle position 55 Tutorial 1 Times Two Tutorial This tutorial introduces the user on how to link Matlab Simulink block diagrams with C source code Introduction Matlab links source code to simulink diagrams using the S Function The S Function is found in the simulink library under the non linear toolbox Refer to the simulink model below xtwo mdl to see how the S Function is used within a Simulink block diagram Notice that the input goes into the S Function and the output comes out of the S Function simple right The diagram is simp
54. nt Once completed the aircraft simulation ran in Matlab s Simulink to compute the aircraft s position and orientation It was then sent from Spiegel to the Graphic computers via the server code where a client on each computer received the aircraft s information and displayed it on the screen The terrain database can be chosen by an initialization file as to whether the database is to be Monterey or Korea The Korean database contains snowy mountains with deep canyons and the Monterey database has an airport with runway lights and glide slope markers The objective is to develop an instrument landing simulation using the Monterey database with the airport and integrate an Instrument Landing System ILS model 2 3 6 D A A D Channel Besides the visual output analog output had to be sent to the cab to drive the instruments To do this the D A and A D cards had to be integrated into the simulation a This was done by developing a class for each card and creating a channel within the class for each input or output Each channel is set and initialized with a channel number and the max input output range 17 2 4 Analog Output The simulation sends the outputs to the instruments with the use of an instrument model This model receives the instrument values and sends them to the cab The values are set to a D A channel on the D A card The card sends the signal on a range of 5 volts to the Trace Card The trace card then connects to the Siblinc
55. ockpit IOS uoo db AA A 22 2 2 2 Rear Cockpit Vd EPA EIU A EN 22 Figure 18 Rear Cockpit Visuals eese 22 Figure 19 Rear Cockpit IOS sosiip pida 22 3 Simulation Operations Procedures coommmomsss 24 3 1 PhEagle Operations Manual o caetero sa vaasa avare ree seo Deed as tese ee e PEE avaa 24 3 2 PhEaele Virtual LIDEAE Vu ceca a lestex NES 24 ERUNT aa 25 o2 LI Suck Mode A yu ey deduce UC yo 25 Figure 20 Stick Model oss eti et iis 25 32 1 2 NOTN MO A dana 26 Figure 21 Engine Model euni ie 26 3 2 1 3 Standard Atmosphere Model eee 27 Figure 22 Standard Atmosphere Model 2T 32 12 SIX DOFPONIOUGL eodein vr Dre perta iT 27 Figure 23 SIGDOP lt a ia 27 3 2 15 Instrument M del ti A dtes 28 Figure 24 Instrument Model esee 28 3 2 AG Grapes Models N o 28 Figure 25 Graphics Model ais iade asen 28 E A ceat debi ecu debueras ses 29 Figure 20188 Model iaa 29 E A oz too dobyto tata ee Rio ena 29 3 2 2 1 Times Two Tutorial eee enn 30 3 2 2 2 Speed of Sound Tutorials ie t t o RH ERES 30 3 2 3 DoCurnientatioli oi SA NA A Ce a 30 4 Simulation Development maana ecce ee ee ee eo oe sete Pee eos t aa aa aa ae taa aa aa naa a aan00000n 31 CMS S CINE E E C I UTI SEM 31 Figure 27 Pilot Venice maksanu 31 Tp T Terrano Datibaseu ite ii 32 Figure 28 Korean Database ivi ii 32 Figure 29
56. or more engineers work on the simulation for a simulator which allows it to become as real as possible Industry simulation labs contain several networked simulators to create a simulation arena The goal of Cal Poly s Flight Simulation Laboratory is to develop a multi role simulator within a simulation arena This will enable the simulator to model any aircraft and will allow several aircraft to fly within the same three dimensional world To accomplish this goal years must be invested to develop the code to run the simulation Simulations are quite complex Flight simulation engineers must not only know basic aircraft dynamics and controls but they must also understand programming networking knowledge hardware standards etc This thesis develops a baseline for achieving the simulation arena goal and sets a standard for training a flight simulation engineer 1 1 Computers and Hardware The flight simulator consists of the Pheagle cab and two analog computers which complete the link between the digital computers The simulation is affordable because it uses four Pentium 166 computers and common software This also allows the communication from the analog realm to be accessed from the digital realm with the use of A D and D A cards Since the digital realm is split into multiple computers the computing power is endless As processors and graphic cards become faster and better the simulation is transportable to any platform More digital a
57. oratory needs to continue its ongoing development This means that running and developing the simulator needs to become easy to learn in the shortest time possible The development of the PhEagle Virtual Library enables senior projects thesis work research and simulation models to be well documented stored and easily accessible so students can begin where the last student finished This will allow the simulator s development to be ongoing and keep up with industry Included are tutorials and demos which teach the students how to create a simulation and learn different aspects of the simulator The Pheagle Operations Manual thoroughly describes how to run the simulator and how to test and calibrate any of the hardware instruments or simulations 1 4 Research Objectives The initial goal was to develop a visual system for the simulator that led to the development of an Instrument Landing System ILS Simulation Before this could happen the simulator had to be moved into the new Northrop Grumman Aerospace System Laboratory in the Advanced Technology Laboratories ATL building at Cal Poly San Luis Obispo shown in Figure 1 This led to the development of the new simulation laboratory i jd Figure 1 Advanced Technologies Laboratories ATL In order for the ILS simulation to work an adequate engine model had to be developed Also the ILS and CDI instruments were not working at the time of development Thes
58. ot have to be in the same directory but for this case it s better to have them in the same directory Type pwd at the command prompt to make sure the path is set to your working directory 5b At the command prompt type mex setup This will bring up the DOS window 5c Select Watcom C C compiler version 10 6 location c watcom y or return 5d Type cmex and the name of the C source file that you wish to create the dll from Make sure that the directory shown at the command prompt is where the source code file is located Then type exit to close the DOS window ie D Projects Test gt cmex timestwo c 6 Now you ve linked the simulink block diagram to the source file and your ready to run the simulation Source Code timestwo c C file written in S Function format that multiplies the input by 2 Pretty hefty file for a simple function xtwo mdl Simulink block diagram that graphically displays the user s input and the produced output 57 Tutorial 2 Speed of Sound Tutorial This tutorial introduces the user on how to link Matlab Simulink block diagrams with multiple inputs and outputs to C source code as well as becoming familiar with the S Function format Introduction This tutorial is similiar to Tutorial 1 except now we are going to have multiple inputs and outputs for the S Function The goal of this tutorial is to create a model that reads 4 inputs gamma R Temp and velocity then calculates the speed of sound and M
59. ote sizeof struct sockaddr_in fprintf stdout slave_init Sent hello to server n if temp 0 perror didn t work exit 1 init host data struct set host_data host_data ownpos x X host_data ownpos y y host data ownpos z z 109 host_data ownrot x psi host data ownrot y theta host data ownrot z phi bufsize sizeof host data buf char malloc sizeof host data fprintf stdout bufsize i bufsize return status FREE REGE SE ohe 2 ohe oko oko oko oko oko oko ok ok ok ok aj aj o al a ls ls ds ls ls ls o oe oe o k k k ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe k ohe oko oko ok ok ok ok ok ok ok sk sk k 2k k k k slave get data Called once per frame by the slave to read the host data and update its graphics as commanded oko fe he o e ohe oje ohe ohe ohe ohe ohe ohe ohe ohe ode ohe ohe ohe ohe ohe oko oko oko oko oko oko oko ok ok ok ok k ok k k a k k k fe fe k k k k k k ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ohe ok ok ohe ok ok ok ok skok int slave get data GV Obi ownship int status G SUCCESS GV_Camera camera int message_len 0 char cameraname 5 110 Get the latest packet that has been broadcast from the master more than one could be backed up in the Ethernet queue len sizeof struct sockaddr in message len recvfrom socket num buf bufsize 0 struct sockaddr amp remote len memcpy amp host data buf sizeof host_data
60. p simulator to the simulation can be accomplished by repeating what was done for the rear cockpit This allows not only combat scenarios but also formation flying As many simulators can be added to the system as long as there is adequate bandwidth 33 4 6 Projectors The Visuals for the PhEagle flight simulator have been proven to work for all three views The next step 1s to determine what type of visual system to use The choices are either monitors or projectors Projector screens can be aligned to offer a wider field of view and give the pilot a better sense of flying Figure 32 gives an example of how to set up the projectors with the use of a screen Figure 32 Projector Setup A projector setup was tested to see how the simulator would look with a three projector system Figure 33 shows the projector displays of the Korean database This was far better than having the thi view gave the pilot a better sense of f the views would blend into the other display would consist of breaks causi Figure 33 Three Projector Display implement the projector system into the simulator three projectors must be purchased The best projectors are projectors designed for flight simulators that allow the picture to be diffused at a close distance In order to implement the projectors a screen needs to be built with concavity and at an arc to encompass the pilot s peripheral vision 4 7 Calibration Originally the simulator was ca
61. r located below the simulator cab shown in Figure 5 A voltage is sent to the motor to enable it to read the stick position and output stick forces The stick acts like a potentiometer and based on Figure 5 Stick Motor the stick position it will send a voltage to the Stick Computer and Siblinc This voltage will then be scaled down based on the potentiometer settings The Spiegel computer requires a voltage range of 5 volts The voltage input is then ran through the trace card to the A D cards located within Spiegel The input is then read in through the compiled C Code and Simulink to generate a nominal input range of 1 0 in decimal form and ready to be run through the simulation 2 1 2 Rudder Rudder inputs are very similar to the stick inputs The rudder inputs are the rudder position velocity and the trim settings Just like the stick the rudder has a torque motor shown in Figure 6 This too acts like a potentiometer and sends a voltage based on the rudder position to the Stick Figure 6 Rudder Torque Motor Computer and Siblinc This voltage will then be scaled down just like the stick to a range of 5 volts and generate a digital value of 1 0 2 1 3 Throttles The throttle input is the right and left throttle setting as well as the buttons located on the throttles Figure 7 shows the two engine throttle configuration in the simulator If the aircraft has two engines each throttle can b
62. raft Data SAD file which contains the aircraft s stability derivatives and initial conditions 25 3 2 1 5 Instrument Model The instrument model in Figure 24 60000 de Atimeter o pe pitch 8 Ball o Roll 8 Ball Constant Constant Yaw Ball receives the inputs from the SixDOF model This Lda lor oye Constanta a pela meter Constant10 o Constant11 F dev point 10 Constant12 Up Rudder Ball model initializes the instruments and sets the e KE sa Constanti Airspeed Constant16 15 TA Side Slip Angle Constant N ie Len eng RPM range of the instruments The model then sends Constant To pit o RPM 1000 Constant2 pl vert Speed 100 Right Nozz 100 plo Left Nozz 2 pe Cd Vert Ind 3 Course Dir Ind Cantant Cd Hor Ind Eonstantea 45 o Hl intemal Press 1900 Right Eng Temp Constant23 em range of 5 volts This communication is done tentat Ei eran Constantes 100000 Left Eng Fuel Constant 6500 P Tot DD Constante 9 e Yau Force through the use of the DA Channel class This is LL Rn 0 Instruments amp Force Constant18 Constant19 the values to the D A cards which convert it to a Constanta
63. rain databases can be added to the simulation as long as they are in the correct format Figure 28 Korean Database Figure 29 Monterey Database 4 1 2 Instrument Landing Simulation The objective of this thesis was to develop an Instrument Landing Simulation complete with an airport and an ILS simulation To make the OpenGVS database compatible with our simulation a coordinate transformation had to be performed The OpenGVS world axis were Z Y X in relation to the aircraft axis X Y Z A simple modification generated the correct output to make the two worlds compatible Finally the bridge between OpenGVS and Simulink had been crossed The Instrument Landing Simulation forces the student pilot to become familiar with the ILS Figure 30 shows a typical takeoff landing scenario for a student pilot s training mission The aircraft can either start two miles away from the airport on the 30 downward approach of the runway or on the airport s taxiway If the aircraft starts at the airport the pilot will takeoff and climb to an altitude of 1 000 feet heading North The pilot will then proceed to enter the landing pattern as they turn South Takeoff Land Figure 30 Takeoff Landing Scenario The pilot needs to align the aircraft with the centerline of the runway using the Course Directional Indicator CDT and Instrument Landing System ILS shown in Figure 31 The CDI shows a range of 10 degrees off centerline Once
64. rated Modular Simulation System for Education and Research California Polytechnic State University San Luis Obispo 1999 SIMULINK Dynamic System Simulation for Matlab The Math Works Inc Writing S Functions 1997 Dale Weems and Headington Programming and Problem Solving with C Jones and Bartlett 1997 Frost Jim Windows Sockets A Quick and Dirty Primer 1999 OpenGVS Programming Guide Version 4 2 Ouantum 3D 1998 Cyber Research Inc Digital VO boards User s Manual 1994 NASA Model II Cockpit Book IV 1979 Barger Robert A PhEagle Operations Manual California Polytechnic State University San Luis Obispo 2000 Ortner Doll Huston Pestal Salluce Stewart Development of an Engine Model Simulation California Polytechnic State University San Luis Obispo 2000 45 14 15 16 17 18 19 20 21 22 23 24 Hill and Peterson Mechanics and Thermodynamics of Propulsion Addison Wesley 1992 Casco and Patangui Development of an Instrument Landing Simulation California Polytechnic State University San Luis Obispo 2000 Rolfe and Staples Flight Simulation Cambridge 1986 Barger Robert A PhEagle Work Packet California Polytechnic State University San Luis Obispo 1999 MATLAB Building GUIs with Matlab The Math Works Inc 1997 Marchand Graphics and GUIs with Matlab CRC Press 1996 Horton Beginning MFC Programming Wrox 1997 Nelson Flight Stability and Automatic
65. re Model This page describes the Standard Atmosphere model and how it works The Standard Atmoshere Model receives the aircraft s current altitude and computes the density pressure temperature and speed of sound at that altitude Source Code std_atm c C file written in S Function format that computes the pressure density temperature and speed of sound for any given altitude Atmosphere mdl Simulink block diagram that graphically displays the inputs and outputs to the C code 53 Standard Atmosphere Model This page describes the Standard Atmosphere model and how it works The Standard Atmoshere Model receives the aircraft s current altitude and computes the density pressure temperature and speed of sound at that altitude Source Code std_atm c C file written in S Function format that computes the pressure density temperature and speed of sound for any given altitude Atmosphere mdl Simulink block diagram that graphically displays the inputs and outputs to the C code 54 Engine Model This page describes the Engine model and how it works The Engine Model calculates the thrust generated by each engine based on the engine type static sea level thrust and the density ratio The 5 engines that are modeled are a propeller piston engine turboprop hi bypass and a turbojet with and without afterburner capability The Engine Model consists of a Spool Up Spool Down Model which gives the engine a realistic feel by addi
66. s to control system design Hopefully this will lead to the development of an Inertial Navigation System INS which will eventually lead to an Aided INS AINS with the use of a Global Positioning System GPS simulation 42 6 Conclusion With the completion of the graphics the PhEagle Flight Simulator is now a complete simulator The simulator cab has a stick rudder and throttles complete with force feedback Accurate models complete with a SixDOF non linear model an engine model an ILS model stick inputs and instrument outputs model atmospheric model and finally a graphics model that displays all three views create an accurate aircraft simulation Real Time Workshop running the model in Simulink keeps the simulation ruming in real time All these aspects of PhEagle make Aeronautical Engineering at Cal Poly unique when compared to other universities The baseline of the simulator is set Further development of the simulator will allow Cal Poly to keep up with industry in the simulation world Further improvements of the simulator are inevitable as students interest has increased due to the advent of graphics The addition of more models is simple with tutorials to teach the students how to generate different types of models The PhEagle Virtual Library will enable the students to document code and models to keep the simulation backed up and updated With the onset of new graphics the visuals will be able to improve to eventually contain
67. set host_data Open_GVS coordinate system is different than Simulation host data ownpos x uPtrs 1 aircrafts y position host data ownpos y uPtrs 2 aircrafts altitude host_data ownpos z uPtrs 0 aircrafts x position host data ownrot x uPtrs 4 pitch host data ownrot y uPtrs 5 yaw host data ownrot z uPtrs 3 bank host data guit 0 send host data to client memcpy buf amp host data sizeof host data n sendto server socket buf sizeof host data O struct sockaddr amp you sizeof struct sockaddr in j SOCKET tep recv setup 99 This function sets the server socket It lets the system determine the port number The function returns the server socket number SOCKET srv_socket 0 struct sockaddr_in local socket address for local side int len sizeof local length of local address create the socket srv socket socket AF INET SOCK DGRAM 0 bind the socket to a port let the system decide the number local sin family AF INET internet family local sin_addr s_addr INADDR_ANY wild card machine address local sin port Service Port choose the port bind srv socket struct sockaddr amp local sizeof local bind the name address to a port return srv socket Function mdlTerminate SS O OS SS 100 Abstract No termination needed but we are required to have th
68. t Y position ft v ACW Aircraft Z position ft APX Airport X position ft T APY Airport Y position ft APZ Airport Z position ft APpsi Airport Heading degrees Outputs CDI Course Deviation Indicator deg 10 scale CDVert Course Deviation Vertical Indicator deg 2 5 scale CDHor Course Deviation Horizontal Indicator deg 2 5 scale Edwin Casco Paul Patangui Robert Barger Cal Poly San Luis Obispo San Luis Obispo CA See simulink src sfuntmpl doc Also see Pheagle HTML Copyright c 1990 1998 by The MathWorks Inc All Rights Reserved Revision 1 3 Define the S Function Name the same as in Simulink model 85 define S FUNCTION NAME ils model Define the S Function Level to be 2 for Models define S FUNCTION LEVEL 2 This header file is necessary for Simulink data structure It is highly suggested to look at this file to see the structure of the S Function Hinclude simstruc h Include any C header files or other files needed for syntax or class definition ftinclude stdio h ftinclude math h Declare local input and output varaible names Inputs double ACX ACY ACZ ACU ACV ACW APX APY APZ APpsi Outputs double CDI CDVert CDHor void Calculate Function mdlInitializeSizes _ SS SO SS SS SS SO O SO SS SO SS SS SO SS SS SO SOS SOS ES 86 Abstract Setup sizes of the
69. t of the states static void mdllnitializeConditions SimStruct S endif MDL_INITIALIZE_CONDITIONS Function mdlOutputs Abstract i simply passes states y n x n static void mdlOutputs SimStruct S int_T tid InputRealPtrsType uPtrs ssGetInputPortRealSignalPtrs S 0 real_T y ssGetOutputPortRealSignal S 0 read in inputs LThrottle uPtrs 0 RThrottle uPtrs 1 1f oldVals 0 LThrottle gt 0 LTauDN 1 25 second time delay on spool down 80 else LTauDN 0 50 second time delay on spool up if oldVals 1 RThrottle gt 0 RTauDN I 25 second time delay on spool down else RTauDN 0 50 second time delay on spool up y 0 LThrottle y 1 RThrottle y 2 LTauDN y 3 RTauDN oldVals 0 LThrottle oldVals 1 RThrottle define MDL UPDATE Change to undef to remove function fif defined MDL UPDATE Function mdlUpdate Abstract This function is called once for every major integration time step Discrete states are typically updated here but this function is useful 81 for performing any tasks that should only take place once per integration step I static void mdlUpdate SimStruct S int T tid endif MDL_UPDATE define MDL_DERIVATIVES Change to undef to remove function if defined MDL DERIVATIVE
70. ter is that it can generate excellent stick and rudder feel since its main purpose was for handling qualities research The stick computer is broken into three sections pitch roll and yaw The three axial forces can be modified for force gradients damping breakout and stop locations Figure 9 shows Figure 9 Stick Computer the stick computer with the different potentiometers located on the front panels Other important features on the analog computer are trim settings surface position and amount of force generated by the motors Each motor has the capability of generating 50 pounds of force 10 2 1 6 Siblinc Siblinc is the other analog computer that controls the channels being sent to and from the cab Figure 10 shows Siblinc with its many channels located on the front panel Each channel has three potentiometers These set the NULL BIAS and SCALE for each channel The middle section of Siblinc contains a patch voltmeter that allows each signal to be monitor coming into Siblinc and going out of Siblinc The bottom section contains additional channels for switches and lights The main purpose of Siblinc 1s to modify the signal going to and from the cab so that the output or input voltage of the cab is scaled to 5 volts for the I O computer Spiegel 2 1 7 Trace Card The trace card is the key to break the gap from the analog realm to the digital realm Figure 11 shows the green trace card located on the b
71. the pilot centers in on the runway within 2 5 degrees the ILS begins to move across the instrument 31 showing the pilot where he needs to position the aircraft to keep the plane centered down the runway Once the plane has acquired the same heading as the runway the pilot must adjust the plane s glide slope to 2 5 degrees The pilot must then maintain the ILS fixed on the centerline and the glide slope in order to make a nice smooth landing Implementation of the ILS simulation proved that the a amp ILS model was accurate since the ILS led the pilot directly Figure 31 CDI amp ILS down the center of the runway to a smooth landing This simulation can now be implemented into the classrooms and students can learn how to takeoff fly a pattern then land using the ILS 4 2 Rear Cockpit Completion of the baseline for the front cockpit gives rise to the addition of a rear cockpit PhEagle is already equipped with a back seat for a navigator The back seat was modified to enable the rear cockpit to be either a navigator or a pilot of a different aircraft Since the rear cockpit does not have an analog stick like the front cockpit the input is purely digital with the use of a gaming stick rudder and throttle This allows the simulation to be entirely digital and run on one machine Once the baseline simulation is copied and created from the front cockpit to the rear the only difference will be to replace the analog
72. their aircraft and implement them into the simulator to see how the aircraft handles This may give rise to the aircraft needing a larger tail for more control authority Also the aircraft might be so unstable that they might need to design a flight control system 40 5 2 Flight Control System Design If the aircraft s stability derivatives are known a flight control system can be designed for that aircraft 22 Glide slope couplers can be designed an implemented into the Instrument Landing Simulation to see if the aircraft can land on its own Figure 29 is a simulation that implements this design Development of an aircraft autopilot would allow students to become more familiar with flight control system design within a six degree of freedom world EM s925 Airspeed 700 knots 0 amp radisee Xt 00 constant to knots gt Atimeter 0 6000 ft I h re ssmma command deg 500 N 25 to Euler q ra rad seo Initial Alt ANA Sum3 pen P ae __ Rolisball 180 deg Range mi vat Bl o r radisec Sum Yaw 180 de 5 Glide Slope Flight gt ii re k Control System GSFCS Constanta meter 440 g s Altitude ft D zap O alpha rad Alpha 10 40 deg Constanta to alt Attit
73. trs 5 Tsl uPtrs 6 TSFCsINAB uPtrs 7 TSFCsIAB uPtrs 8 rho uPtrs 9 a uPtrs 10 Vtrue uPtrs 1 1 NumEng uPtrs 12 Calculate the Engine States Calculate Assign the Outputs y 0 RFuelFlo y 1 LFuelFlo y 2 RThrust y 3 LThrust y 4 RNoz y 5 LNoz 67 y 6 RRPM y 7 LRPM y 8 R Temp y 9 L Temp end model outputs void Calculate const float rhosl 2 0 002377 slug ft3 float asl 1116 2 ft s float Thrust float TSFC float FuelFlow Propeller Engine Engine Type 1 if EngType 1 Thrust Tsl 550 rho rhosl Np Vtrue 1 69 Tsl shp if NumEng 1 RThrust 0 5 RThrottle Thrust LThrust 0 5 LThrottle Thrust printf RThrust1 1 i n RThrust printf LThrust1 1 i n LThrust else if NumEng 2 68 RThrust RThrottle Thrust LThrust LThrottle Thrust printf RThrust1 2 i n RThrust printf LThrust1 2 i n LThrust Turboprop Engine Engine Type 2 if EngType 2 Thrust Ts1 550 rho rhosl Np Vtrue 1 69 Tsl eshp if NumEng 1 RThrust 0 5 RThrottle Thrust LThrust 0 5 RThrottle Thrust printf RThrust2 1 i n RThrust printf LThrust2 1 i n LThrust else RThrust RThrottle Thrust LThrust LThrottle Thrust printf RThrust2 2 i n RThrust printf LThrust2 2 i n LThrust 69 High By pass Engine Engine Type 3 if EngType 3 Thrust 0 1
74. ude ft pann Gamma deg Beta 1 15 deg o O beta rad FL Distance ni nme Psi rad psi deg Theta Lrpm 10 110 Range ft mi Distance ft r Mu tseo from TO l velocity ftis 2306 Vert speed 6000 ft min rr Decay Theta rad Theta deg Phi ase Yaw Force 1 Constant Roll Force 1 o Hu tt sec Phi rad WejPhi deg Psi Pitch Force 1 Constanti Instruments amp Force Euler Transform to deg Figure 37 Glide Slope Simulation 5 3 VFR and IFR Landing Simulations The simulator is now set up to perform either Visual Flight Rules VFR or Instrument Flight Rules IFR Landing Simulations The simulation is already set to run for VFR conditions To fly in IFR conditions the canopy hood can be lowered and the visibility and cloud layer can be set within the OpenGVS environment to simulate IFR conditions The time of day can be set to perform night landings Also with the ILS simulation the pilot should be able to fly with no graphics to the airport s runway 41 5 4 Guidance and Controls The simulator can now incorporate Guidance and Control theory design into the simulations Students in Guidance and Control can experience the use of PID controllers compare closed loop design with open loop design and study classical control techniques for an entire simulation with six degrees of freedom These students will get an early exposure to the simulator and realize the importance that this simulator hold
75. uts are left and right engine fuel capacity propeller efficiency if a propeller driven engine TSFC and afterburner TSFC It then computes the thrust generated based on these inputs and calculates the engine RPM temperature fuel flow and nozzle position Cari Compe 5 op a auta m E Teri Figure 21 Engine Model 24 3 2 1 3 Standard Atmosphere Model The Standard Atmosphere Model 1s shown in Figure 22 This model E Display3 computes the speed of sound density Pressure lin a At ft Display2 pressure and temperature based on Songan Density stugt p a ft sec gt 1117 Subsystem Display altitude This model also takes into account the different altitude regimes that Figure 22 Standard Atmosphere Model the aircraft is flying in and applies the appropriate equations 3 2 1 4 SixDOF Model This model computes the zF SE A aircraft s position and orientation al Bee isa along with velocity angular rates J angle of attack sideslip and translational accelerations The i m UAR EM a a SixDOF model in Figure 23 treats i E the aircraft like a point mass It Figure 23 SixDOF Model converts the forces moments and control inputs generated by the aircraft to compute the above states The term six degrees of freedom refers to the translational and rotational positions X Y Z and Psi Theta Phi The model also reads in a Standard Airc
76. voltage at nearly the same location at the throttle midpoint This concludes that the NULL and BIAS settings need little adjustment Also by changing the SCALE the slope of the left throttle voltage curve will decrease to match the right throttle s slope Decreasing the SCALE will decrease the voltage outputs well as decreasing the slope of the voltage curve 37 By adjusting the potentiometer Analog Signals settings the final graph displays the corrected output in Figure 36 Both throttles follow each other s output with little error Originally the error in the throttle was Voltage V up to 16 After calibration this error e R Throttle TNK was reduced 1 296 A slight amount of F L Throttle TNK backlash was found in the throttle due to hysteresis This will need to be X pos assessed in the future Figure 35 Throttle Analog Output Throttle Calibration e R Throttle m amp L Throttle Position Figure 36 Corrected Throttle Output 38 4 8 Graphical User Interface GUD A graphical user interface will allow different options to be changed easily within the simulation Matlab already has a Graphical User Interface Design Environment GUIDE that would allow GUI implementation to be easy to add into the simulation 18 This GUI will allow the user to input different initial conditions such as airport or database location wind and atmospheric conditions a

Developement Of An Instrument Landing Simulation Using MATLAB

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