1. IEEE Region 6 Student Paper Contest, Anaheim CA, September 17 th 1998 Chen-I Lim Arizona State University http://www.eas.asu.edu/~aar/research/mosart/Presentations/Heli/index.htm An Interactive Modeling, Simulation, Animation, and Real-Time Control (MoSART) Helicopter Environment

2. Motivation System Dynamics Description of Interactive MoSART Environment Utility of Environment Summary and Future Directions Outline

3. Advanced visualization tools are needed for system analysis and design. Research/education can be enhanced with interactive multimedia environments. PC platforms now offer substantial computing power for engineering design. Motivation

4. New Technologies Affordable and fast computing (PCs) Hi-fidelity simulation capability - Simulink / MATLAB, etc. Hi-fidelity animation capability - 3D modeling software (e.g. 3D Studio, etc.) - Microsoft Direct-3D Object-oriented programming (OOP) Framework - Active-X / OLE

5. Working Model (Knowledge Revolution) DADS/Plant (CADSI) …generic, not optimized for specific systems (both have contributed to development of MoSART facility at ASU) State of the Art

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

7. Real-time simulation Alter model/controller: - structure - parameters (on-the-fly) Advanced visualization: - real-time graphics - visual indicators/aids - 3D animation models Direct user input via joystick Integration with MATLAB: advanced CAD tools Key Environment Features

8. Robotic Manipulator High-Performance Aircraft Missile-Target Engagements Pendulums: Inverted, Rotary, Multi-link... Adaptive Algorithms/Learning Systems Submarine Environment Other Interactive Environments Being Developed at MoSART Facility

9. Aerodynamic Derivatives Near Hover Sikorsky UH-60 Blackhawk

10. Vertical Dynamics Longitudinal Dynamics Basic Helicopter Dynamics Near Hover

11. - Collective control Open loop poles: Vertical Dynamics Near Hover

12. Longitudinal Dynamics Near Hover State Space Representation: B lc - Cyclic control Unstable: backflapping mode Open loop poles: …need AFCS to minimize pilot workload θ 010θ0 θ =0M q M u θ +M Blc B lc x-g0X u xx Blc..... Horizontal damping mode X/ B lc. θ / B lc

13. Open loop poles & zeros: Zero near origin Transfer function: Longitudinal Dynamics Near Hover Performance-Pitch Tradeoff:

14. Unstable: backflapping mode Open loop poles & zeros: Horizontal damping mode Horizontal Speed Dynamics: Longitudinal Dynamics Near Hover

15. Open loop poles & zeros: Lightly damped zero Longitudinal Dynamics Near Hover Horizontal Pitch Dynamics:

16. General System Diagram

17. Horizontal Speed Controller Horizontal Speed Dynamics (s+1) 2 (2500) ( s + 50 ) 2 k (s+2.5) s. Desired speed Speed, x - + Cyclic control, B lc

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

19. Pentium PC Windows ’95/NT System Requirements: Pentium PC running Windows 95/NT. 32 MB RAM. Direct-3D 3.0. Recommended: Pentium II 266 w/ MMX running Windows NT 4.0. 64 MB RAM. Direct-3D 3.0. Visual C++/ MFC Direct-3D v3.0 MATLAB Engine v5.0 About the Program

20. Program User Interface Simulation Module Graphical Animation Module Help-Instruct Module (PUI) (SIM) (GAM) (HIM) Environment Structure

21. (PUI) User Friendly Windows ’95/NT Interface Menus Multiple windows Control toolbars Interactive System Diagram Block diagram representation of system Point-and-click access Program User Interface

22. Edit system parameters on-the-fly Change reference commands: - Signal generator - User joystick input Call up real-time graphs of signals & outputs Activate or deactivate a block Through the point-and-click system diagram interface, a user can: Use of the PUI

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

24. Changing plant parameters on-the-fly Playback of externally generated simulation: e.g. MATLAB/SIMULINK Dynamic linking: MATLAB Engine... (Edit Mode) (Playback Mode) (External-Link Mode) Simulation Module: Extensibility

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

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

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

28. Utility of Environment Unstable backflapping mode Open-loop joystick control Closed-loop user joystick control: without command pre-filter Closed-loop user joystick control: with command pre-filter

29. Versatile system-specific interactive MoSART environments Windows / C++ / Direct3D / MATLAB User friendly: accessible & intuitive User can alter system model structure & parameters (on-the-fly) Highly extensible: can incorporate new simulation/animation models Summary

30. More visual indicators Advanced SIM and GAM Expanded HIM: web support, multimedia Enhanced integration with MATLAB Integrated design & analysis environment Online presentation available at: … development of MoSART Facility at ASU Future Directions http://www.eas.asu.edu/~aar/research/mosart/Presentations/Heli/index.htm