Open Items

The following items were open from October 1st:

  • Check on availability of X-56A models
  • Send doodle polls to find recurring meeting times
  • Start getting preliminary data to the team to start working on models, control laws, MDAO
  • UMN to define signal names and interfaces

In response:

  • We received an X-56A FEM, which was validated with GVT data, an X-56A OML CAD suitable for developing CFD models, and a detailed X-56A CAD.
  • The following days and times are suitable for group meetings, all times are given for the Central Time zone:
    • Monday 1600
    • Tuesday 1000, 1600
    • Wednesday 1600
    • Thursday 1000, 1400
  • We’ve started getting X-56A data to VT to begin MDAO work, we’ll be putting out BFF and mini MUTT data as well. Initially this is being done through dropbox, but we’ll transition to using git repositories so that we have version control.
  • We haven’t defined signal names or interfaces yet, we’ll hold this item open.

mAEWing1 and mAEWing2

We scaled the X-56A outer mold line to a 10 ft wingspan and overlayed this with the BFF outer mold line. The main difference discovered is that X-56 has a more slender wing. To reduce schedule risk in year 1, we decided to baseline mAEWing1 on the BFF aircraft and mAEWing2 will be baselined on a scaled X-56A aircraft. The implications of this decision are that MDAO research and CFD will be conducted on the scaled X-56A in preparation for choosing the optimal control surface layout, structural design, and sensors for mAEWing2. mAEWing1 will use DLM and FEM developed from the BFF aircraft, but no CFD or MDAO.

mAEWing1

This aircraft will be constructed as close to BFF as possible (similar flexibility and control surface layout). We will demonstrate flutter suppression and shape modification on this airframe. Initially this will be done with dedicated flutter suppression surfaces before moving toward an optimal allocation scheme. Information on the physical aircraft (OML and GVT) is in the process of being put online. The next items needed for this approach is a DLM and FEM model followed by preliminary control law design. Dave Schmidt’s approach of using Datcom to develop a preliminary model is an alternative approach that will be explored.

mAEWing2

This aircraft will be based on a scaled down X-56A outer mold line. Open parameters for optimization are the control surface layout (number of effectors, leading edge devices, trailing edge devices), determining the amount and type of flexibility (bending, torsion), and determining the optimal number and type of sensors. Again flutter suppression and shape modification will be demonstrated with an optimal allocation scheme. Following initial testing an elastic membrane will be installed to demonstrate conformal mold line.

Wind Tunnel Testing

UMN is currently in the process of wind tunnel testing a 40” BFF model to gather steady aerodynamic data. Gathered data will include: CLa, CLd, Cma, Cmd, Cnd, Cld where d is control surface deflection. We will investigate whether VT’s wind tunnel can be used to gather dynamic derivatives (i.e. based on p, q, r).

To Do

  • Add all members to the website contact list
  • Develop cost estimates for VT wind tunnel testing
  • Distribute X-56, BFF, and mini MUTT physical data
  • Begin preliminary aerodynamic and structural model development for mAEWing1
  • Begin MDAO research and CFD development for mAEWing2
  • UMN to define signal names and interfaces

Update 20141024

Bringing back up the capability to measure dynamic derivatives in VT’s wind tunnel was determined to be out of scope for the program. Planning to capture rigid aircraft aerodynamic derivatives in flight testing and in flight system identification of the mini MUTT aircraft.