UAV Flight Simulation: Credibility of Linear Decoupled vs. Nonlinear Coupled Equations of Motion

The dynamical modeling of an Unmanned Air Vehicle (UAV) forms the heart of its simulation. The equations of motion can take five different forms: 1) nonlinear fully coupled, 2) nonlinear semi-coupled, 3) nonlinear decoupled, 4) linear coupled, and 5) linear decoupled. In the fully coupled equations of motion, two new coupling stability derivatives ( ! D C , ! L C ) are incorporated. The main purpose of this paper is to compare each version of the equations of motion, and to demonstrate positive and negative features of each form. This paper also compares the five different dynamical models using eight distinct UAV missions. It analyzes them from three different aspects, and gives recommendations for which model is best for a specified mission. MATLAB/Simulink is used to implementation the simulation. The final results are compared by analyzing the resulting trajectories and control deflections.

[1]  Phillip R. Chandler,et al.  MultiUAV: a multiple UAV simulation for investigation of cooperative control , 2002, Proceedings of the Winter Simulation Conference.

[2]  Jackson E. Bruce.  Results of a Flight Simulation Software Methods Survey , 1995 .

[3]  Harald Buschek,et al.  Self-scheduled missile autopilot using parameter-varying robust control , 1998 .

[4]  Ken A. Norlin.  Flight simulation software at NASA Dryden Flight Research Center , 1995 .

[5]  Frank L. Lewis,et al.  Aircraft Control and Simulation , 1992 .

[6]  Mario Sznaier,et al.  Robust Systems Theory and Applications , 1998 .

[7]  Daigoro Ito,et al.  AIAA 2001-4380 Robust Dynamic Inversion Controller Design and Analysis for the X-38 , 2001 .

[8]  Michael B. McFarland,et al.  ROBUSTNESS OF A NONLINEAR MISSILE AUTOPILOT DESIGNED USING DYNAMIC INVERSION , 2000 .

[9]  William L. Garrard,et al.  Nonlinear inversion flight control for a supermaneuverable aircraft , 1992 .

[10]  Robert F. Stengel,et al.  Robust Nonlinear Control of a Hypersonic Aircraft , 1999 .

[11]  Marc L. Steinberg,et al.  HIGH-FIDELITY SIMULATION TESTING OF CONTROL ALLOCATION METHODS , 2002 .

[12]  Leonard Meirovitch,et al.  Unified theory for the dynamics and control of maneuvering flexible aircraft , 2004 .

[13]  Jonathan R. Bar-On,et al.  Linearization of a Six-Degree-of-Freedom Missile for Autopilot Analysis , 1998 .

[14]  Marc Rauw,et al.  FDC 1.2 - A Simulink Toolbox for Flight Dynamics and Control Analysis , 2001 .

[15]  Ernest J. Ohlmeyer,et al.  Nonlinear missile autopilot design using time-scale separation , 1997 .

[16]  Dale Enns,et al.  AN APPROACH TO SELECT DESIRED DYNAMICS GAINS FOR DYNAMIC INVERSION CONTROL LAWS , 1997 .

[17]  James Nichols,et al.  CASTLE: The Next Generation of Navy Flight Simulation , 2001 .

[18]  Gul Agha,et al.  AN ACTOR-BASED SIMULATION FOR STUDYING UAV COORDINATION , 2003 .

[19]  H. Buschek.  FULL ENVELOPE MISSILE AUTOPILOT DESIGN USING GAIN SCHEDULED ROBUST CONTROL , 1999 .