Home | Members | Research | Facilities | Publications | Software | News | Contact


 

   

Novel Wing Morphing Actuator : Modeling and Experiments

The morphing wing project at Texas A& M University is principally focussed at understanding the aerodynamic response a reconfigurable wing produces upon actuation. This effort includes development of theoretical models for such actuators and their performance evaluation when compared to conventional schemes of aerodynamic actuation. The knowledge and experience thus acquired, is expected to culminate in tracking demonstrations of lift and moment reference trajectories, ultimately paving way to the development of effective actuators and models.

A simple experiment was designed to study the aerodynamic response of the The morphing wing design proposed is simple in the fact that simple aerodynamic theory could be used to model the experiment. The wing consists of an elastic structure (ABS plastic material) and is covered with an elastomeric skin. The elastic structure has front and rear supports at the leading and trailing edge to retain the air foil shape during operation. Design calculations for the various parameters were obtained by subjecting finite element
models to loads predicted by CFD simulations. The skin and the structure along with some sample structural calculation results are shown in figure 1. The Geometric properties of the wing and the tunnel operating conditions for the experiment are detailed in appendix A. The structure of the wing is rigidly coupled to four telescoping tubes independently which are attached to the wing at four locations along the span. This facilitates the twisting of the wing at these four locations. The root location was used to change the angle of attack (AOA) of the wing. The other twistable sections are located at every 1/3rd spanwise station (tip section S1, Middle Section S2, First Section L3) from the root section until the tip section. This entire telescoping tube arrangement is connected to relatively placed servos which work to twist corresponding sections along the span. The actuators are commanded from a dedicated processing board (by DSPACER). The loads are sensed by a 6 degree of freedom ATI industialR load cell. The sensed loads are received at the computer via a National InstrumentsR Data Acquisition card and recorded in to a file via Labview SoftwareR. This architecture is presented in figure 2.

Structure Design

Figure 1: Structure and Skin design with corresponding calculations.

Experimental Setup

Figure 2: Experimental Setup

Pictures of the test setup
Wing In the Tunnel Testing in Progress

Test Results

The results obtained from experiments are compared with models based on Lifting line theory of aerodynamics.

Base Line Tests

Base Line test : All angles fixed to align with the root angle of attack (test corresponding to NACA 0015 fixed wing test)

Tip Section Sensitivity Calculations

Tip section sensitivity test : Tip section is tested at all possible angles within its range while the rest of the sections are held close to angle of attack which is held at four different operating points

Flow Visualization Pictures
High Angles of Attack High Angle of Attack -No Stall
Note that at 15 degree tip angle of attack, the wing does not stall, increasing the flight envelope of the actuator.
Vortices at Trailing Edge
Flow Visualization Video Links

Video 1>>

Video 2 >>

Video 3 >>

Click Here for Info on Synthetic Jet Actuators:

Other related links:

  1. Survey of Efforts from Various Communities (last updated cir. 2005)
  2. Our Early Results (cir. 2004)

Publications

  1. Majji, M., Rediniotis, O. K., and Junkins, J. L., “Design of a Morphing Wing : Modeling and Experiments,” Accepted, AIAA Guidance Navigation and Control Conference, 2007.
  2. Majji, M., and Junkins, J. L., “Total Least Squares Estimation of Dynamic Systems,” Accepted, AIAA Guidance Navigation and Control Conference, 2007

Reports

  1. Reifschneider, J., Majji, M., Mohan, G., Junkins, J. L., and Rediniotis, O. K., "Design of a Morphing Wing", Tiims USRG Report, August 2004.
  2. Sunil C. Patel, Manoranjan Majji, Bong Su Koh, John L. Junkins, Othon K. Rediniotis., "Morphing Wing: A Demonstration of Aero Servo Elastic Distributed Sensing and Control", Tiims USRG Report, August 2005.

 

 



 


© Aerospace Engineering, Texas A&M University