These last weeks have been quite a challenge with mounting school work and even a brief hospitalization (appendicitis).  Despite this my team and I have made great progress on our UAV.  The aircraft also has a name now “Vindication”.  We named the aircraft as such, because when completed. that it what the aircraft will become for all our hard work.

To address the challenge of creating a multi-configuration UAV I came up with the idea of using wing plate extensions.  However, in adding these extensions we did not want to have to readjust the center of gravity in order to maintain a static margin of 10%.  Thus the extensions are designed such that the change in neutral point due to the extensions is equal to the change in the center of gravity due to the added weight of the extensions.  This resulted in what we have been calling the “Lambda Wing” because of it’s transition from a swept wing to the straight wing.

AVL-LS

Low Speed Configuration

There is still a long way to go.  The next step will be to model the aircraft in Cmarc which when properly completed will be considered our truth model.

High Speed Configuration

High Speed Configuration

Both of these aircraft’s models were generated using the Mavl tool.  The tool’s functionality has grown considerably since its last mention hear, but it is interesting to note the the total line count has actually stayed almost constant at 1500 lines for the last eight weeks.  The rate at which code has been compressed has very coincidentally matched the rate at which new code is being added.  The Mavl tool is now fully capable of modelling an arbitrary aircraft (including control surfaces) as well as analyzing the stability and performance of the resultant aircraft.  The analysis tools include stall and cruise speed calculations thanks to the XFoil bridge being added.  It goes without saying that the tool is also capable of classifying the eigenvalues produced by AVL to determine the flight modes of the aircraft.  There is even a tool for correlating the flight modes to the handling levels as defined in MIL-F-8785.