An Interactive Modeling Simulation Animation and Real-Time Control

An Interactive Modeling, Simulation, Animation, and Real-Time Control (Mo. SART) Twin-Lift Helicopter System Environment Chen-I Lim Richard P. Metzger, Jr. Armando A. Rodriguez American Control Conference June 3 rd 1999 Hyatt Regency, San Diego, CA Ack : White House , NSF, WAESO/CIMD, Boeing, Intel, Microsoft, CADSI, Knowledge Revolution, Math. Works, Lego, Xilinx, Honeywell, National Instruments, Integrated Systems, ASU CIEE. http: //www. eas. asu. edu/~aar/research/mosart/Presentations

New Technologies • Affordable High Performance Computing • Hi-fidelity Simulation Capability – Simulink / MATLAB, etc… – Visual C++ • PC Animation Creation / Manipulation Technologies – 3 D Modeling Software (e. g. 3 D Studio, RPM D 3 D toolbox, etc. ) – Microsoft Direct. X (provides: 3 D-animation, sound, video, user-input, etc. ) • Object Oriented Programming (OOP) Framework – Active. X / OLE

Key Environment Features • Accelerated-time simulation • Alter model/controller: – structure – parameters (on-the-fly) • Advanced visualization: – real-time graphics – visual indicators/aids – 3 D animation models • Direct user input via joystick, mouse, etc. • Integration with MATLAB and Simulink

Contributions of Work System-specific interactive Mo. SART environments High performance: Windows/ C++ Advanced visualization tools: Direct-3 D Extensible: integration with MATLAB User friendly

Sikorsky UH-60 Blackhawk Aerodynamic Derivatives Near Hover

Longitudinal Dynamics Near Hover State Space Representation: . . . x 0 = 1 0 0 Mq Mu -g 0 Xu x . . 0 + MBlc x. Blc - Cyclic control Open loop poles: Horizontal damping mode / Blc Unstable: backflapping mode. X/ Blc …need AFCS to minimize pilot workload

General System Diagram

Horizontal Speed Controller Desired speed + - k (s+a) s Cyclic control, Blc Horizontal Speed Dynamics . Speed, x (s+b)2 (2500) ( s + 50 )2 b 2 a = 2. 5 b = 0. 6 k = 0. 5 e-3

About the Program MATLAB Engine Direct-3 D v 3. 0 v 5. 0 Visual C++/ MFC Windows ’ 95/’ 98/NT Pentium PC System Requirements: Pentium PC running Windows 95/NT. 32 MB RAM. Direct-3 D 3. 0. Recommended: Pentium II 266 w/ MMX running Windows NT 4. 0. 64 MB RAM. Direct-3 D 3. 0.

Interactive Mo. SART Environment Modules Interactive Environment Application Program User Interface (PUI) Simulation Module (SIM) Graphical Animation Module (GAM) Help/Instruct Module (HIM) Communication Module (COM) Physical System Simulink MATLAB Other Applications Active. X Internet

Program User Interface UI) (P User Friendly Windows ’ 95/NT Interface • Menus • Multiple windows • Program control toolbars Interactive System Diagram • Block diagram representation of system • Point-and-click access

Program interface

Simulation Module (SIM) Numerical Simulation • Fast compiled C++: >3000 Hz / 266 MHz PII • Better than real-time simulation On-the-Fly Parameter Editing • Plant models • Controller parameters • Reference Commands, Disturbances, Noise, etc. • Integration methods: Euler, Runge-Kutta 4, etc. Extensibility

Simulation Module: Extensibility Changing plant parameters on-the-fly ) dit Mode (E Playback of externally generated simulation: e. g. MATLAB/SIMULINK ) ack Mode (Playb Dynamic linking: MATLAB Engine. . . (E e) Link Mod xternal-

Graphical Animation Module M) (GA 3 D Animation • Direct-3 D • Texture-mapped, light-shaded polygons • Wireframe copters from previous simulations (SMAC) Visualization Tools & Indicators • Real-Time Variable Display Window • 2 D Animation Window: pitch indicator • Real-time multiple-graph plotting Extensibility

Animation Module: Extensibility Direct-3 D standard file format 3 D modeling packages: e. g. 3 D Studio Libraries of 3 D objects widely available: Internet & commercial vendors.

Help-Instruct Module On-line Help • Instructions on using the environment • Program reference HTML / PDF Documents • Model documentation/ references • Interactive tutorials IM) (H

Utility of Environment Open-loop joystick control Closed-loop user joystick control TLHS: Modal Analysis TLHS: Command Following

Open-Loop Joystick Control Undesirable level of pitching. Very difficult to maintain a desired pitch attitude Very oscillatory cyclic control Difficult to maintain a desired speed

Closed-Loop Command Following Acceptable levels of pitching Smooth cyclic control response Good acceleration and smooth speed transient

TLHS System Configuration Master Slave Spreader Bar Payload

TLHS System Poles TLHS open-loop poles 3 AVM SM ASM 2 Vertical Spring Horizontal Spring Backflapping Imaginary Axis 1 Symmetric Damping 0 Average Vertical Damping -1 Tethered Helicopter Anti-Symmetric Damping -2 Pendular -3 -2. 5 -2 -1. 5 -1 -0. 5 Real Axis 0 0. 5 1

TLHS: Modal Analysis

TLHS: Command Following Command: 5 ft/sec forward speed 5 ft/sec climb

TLHS: Command Following

Future Directions • More visual indicators • Advanced SIM and GAM (e. g. TLHS) • Expanded HIM: web support, multimedia – Develop Model Documentation Feature • Enhanced integration with MATLAB / SIMULINK / • • LABVIEW / Excel…. all are Active. X Compatible Integrated design & analysis environment Develop Additional Environments … development of Facility VISIT: http: //www. eas. asu. edu/~aar/research/mosart/Presentations/

END OF PRESENTATION Some auxilary slides follow

Horizontal Speed Controller #1 (proportional only) Controller #2 (Dynamical Feedback)

Unstable Backflapping Mode

TLHS: Loop Transfer Function

TLHS: Sensitivity

TLHS: Complementary Sensitivity