Methods for Compensating for Control Allocator and Actuator Interactions

In this work, a method, which post-processes the output of a control allocation algorithm, is developed to compensate for actuator dynamics. In reaching this objective, it is of great importance to consider the real-world applicability of the approach. In order to obtain an algorithm which can operate in real-time on a typical ∞ight computer, it is pertinent to not add to the complexity of the constrained control allocation algorithm. Likewise, it is necessary to develop an approach that is applicable to both the saturated and unsaturated control efiector cases. One method which can accomplish these goals is to post-process the output of the control allocation algorithm to overdrive the actuators so that at the end of a sampling interval, the actual actuator positions are equivalent to the desired actuator positions. This is the approach taken in this work and it yields a simple, but efiective, means of compensating for actuator dynamics.

[1]  Ola Härkegård.  Dynamic Control Allocation Using Constrained Quadratic Programming , 2002 .

[2]  R. G. Cottrell.  Optimal intercept guidance for short-range tactical missiles , 1971 .

[3]  R. Venkataraman,et al.  A new control allocation method that accounts for effector dynamics , 2004, 2004 IEEE Aerospace Conference Proceedings (IEEE Cat. No.04TH8720).

[4]  Marc Bodson,et al.  Evaluation of optimization methods for control allocation , 2001 .

[5]  James F Buffington.  Modular Control Law Design for the Innovative Control Effectors (ICE) Tailless Fighter Aircraft Configuration 101-3 , 1999 .

[6]  Ilan Rusnak,et al.  Optimal guidance for acceleration constrained missile and maneuvering target , 1990 .

[7]  M. Bolender,et al.  Non-Linear Control Allocation Using Piecewise Linear Functions , 2006 .

[8]  Wayne C. Durham.  Constrained Control Allocation , 1992 .

[9]  Thomas R. Blackburn,et al.  Method for improving autopilot lag compensation in intercept guidance , 1996 .

[10]  Wayne C. Durham.  Attainable moments for the constrained control allocation problem , 1994 .

[11]  D. Enns.  CONTROL ALLOCATION APPROACHES , 1998 .

[12]  David B. Doman,et al.  IMPROVING CONTROL ALLOCATION ACCURACY FOR NONLINEAR AIRCRAFT DYNAMICS , 2002 .

[13]  John Glenn Bolling,et al.  Implementation of Constrained Control Allocation Techniques Using an Aerodynamic Model of an F-15 Aircraft , 1997 .

[14]  Mohammad-Ali Massoumnia,et al.  An optimal mid-course guidance law for fixed-interval propulsive maneuvers , 1995 .

[15]  A. Page,et al.  A CLOSED-LOOP COMPARISON OF CONTROL ALLOCATION METHODS , 2000 .

[16]  M. Bolender,et al.  Nonlinear Control Allocation Using Piecewise Linear Functions , 2003 .

[17]  Wayne C. Durham.  Constrained control allocation - Three-moment problem , 1994 .

[18]  D.B. Doman,et al.  A Method for Compensation of Interactions Between Second-Order Actuators and Control Allocators , 2005, 2005 IEEE Aerospace Conference.