Development of a Shape Memory Alloy-based Micro-Flow Effector for Missile Side Force Control

Actuation systems for aerovehicles have traditionally been based on hydraulic or electromechanical systems because large control surfaces are needed to generate sufficient control authority. Active flow control systems rely on the ability of small flow effectors to trigger or stabilize flow structures to generate aerodynamic forces. In a previous study, wind tunnel tests showed that a proportional side force magnitude could be obtained by indexing static micro-flow effectors at various angular positions on the model nose. To develop a dynamic micro-flow effector assembly that would fit in the available missile model nose volume, shape memory alloy (SMA) wire was selected as an actuation material due to its force and displacement characteristics. A compliant link was designed to act as a transmission between the SMA actuator and the micro-flow effector. The performance of the SMA-actuated micro-flow effector was first evaluated under open-loop conditions. The results from a hybrid SMA model based on microstructural modeling and macroscopic phase kinetics compared well with the experimental data. The dynamics of the actuated micro-flow effector was characterized through a system identification technique. A two-step variable structure controller was synthesized using experimental data to obtain flow effector tip position control. Closed-loop test results showed that the control law was capable of providing effective control up to 0.5 Hz. An actuator assembly consisting of four SMAactuated micro-flow effectors was built and installed in the nose cone of a wind tunnel missile model. Results showed that good position control of the flow effector tip was maintained under wind-on and wind-off condition. The wind tunnel data showed that the side force was a nonlinear function of the flow effector deployment height. Positive or negative side forces were generated by actuating the port-side or starboard-side, respectively, micro-flow effectors located on the missile nose cone.

[1]  Peter H. Meckl,et al.  Enhanced Cooling of Shape Memory Alloy Wires Using Semiconductor "Heat Pump" Modules , 1994 .

[2]  Ron Barrett,et al.  Modeling, design, and testing of a barrel-launched adaptive munition , 1997, Smart Structures.

[3]  M G Faulkner,et al.  Development of a shape memory alloy actuator for a robotic eye prosthesis , 2005 .

[4]  L. Brinson.  One-Dimensional Constitutive Behavior of Shape Memory Alloys: Thermomechanical Derivation with Non-Constant Material Functions and Redefined Martensite Internal Variable , 1993 .

[5]  Craig A. Rogers,et al.  Design of Shape Memory Alloy Actuators , 1992 .

[6]  Wei Min Huang,et al.  Modified Shape Memory Alloy (SMA) Model for SMA Wire Based Actuator Design , 1999 .

[7]  Mehdi Ahmadian,et al.  Design of a Kalman filter for rotary shape memory alloy actuators , 2004 .

[8]  Patrick Terriault,et al.  Hybrid micro-macro-mechanical constitutive model for shape-memory alloys , 2005, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[9]  Karl Johan Åström,et al.  Computer-Controlled Systems: Theory and Design , 1984 .

[10]  Pierre Perrier,et al.  Multiscale Active Flow Control , 1998 .

[11]  Dimitris C. Lagoudas,et al.  On the role of thermoelectric heat transfer in the design of SMA actuators: theoretical modeling and experiment , 1995 .

[12]  E. Patoor,et al.  Thermomechanical behaviour of shape memory alloys , 1988 .

[13]  Vincent Hayward,et al.  Phase control approach to hysteresis reduction , 2001, IEEE Trans. Control. Syst. Technol..

[14]  Lennart Ljung,et al.  System Identification: Theory for the User , 1987 .

[15]  Franklin Wong,et al.  Side Force Generation Mechanism for a Missile with Nose-Mounted Micro-Structures , 2006 .

[16]  Ron Barrett,et al.  Active aeroelastic tailoring of an adaptive Flexspar stabilator , 1996 .

[17]  Carl P. Tilmann,et al.  Closed-Loop Missile Yaw Control via Manipulation of Forebody Flow Asymmetrics , 2004 .