I am doing some analysis and simulations on UAV ground-maneuver. As very well known in the literature, the 6DOF model is a good dynamical model for airplane's dynamics. I intend to use that to analyse UAV dynamics during a ground-maneuver or takeoff stage, taking into account all affecting forces including tires' frictions etc.
On the ground, the nose gear direction angle will introduce a slip angle, and there will be a net slip angle from the whole UAV. However, conventionally, the slip angle is the one that is related to the wind effect, just like the angle of attack, but in different plane, and those are considerable parameters for the aerodynamic coefficient calculations.
My point is, how to integrate both slip angles in the dynamical model - the one coming from the tires as well as for the one coming from the wind disturbance?
I hope I made my point as clear as possible, and hope the people who are interested and experts can help me on this, as it's part of PhD work; it's not a target, though.
This is a related reference,
https://www2.lirmm.fr/lirmm/interne/BIBLI/CDROM/ROB/2009/DETC_2009/DETC2009/data/pdfs/trk-4/DETC2009-86293.pdf
If i understand it right, You must simply algebrically sum the tire and the Wind sideslip to have an equivalent Wind 'total' sideslip ..
I think you simply have to add them both. Be careful though with the signs. Landing gear alignment is related to airplane orientation with respect to an inertial frame of reference (the angle psi) and wind orientation with respect to airplane body X-axis in XY plane is related to the angle of sideslip beta. The relation between the angles is:
beta (sideslip angle) = chi (wind orientation angle with respect to inertial Earth-fixed X_E) - psi(body X-axis orientation with respect to inertial Earth-fixed X_E). This simple relation will hold only in XY plane and can get complicated if you include other degrees of freedom.
Sorry, using this space to divert your attention to a new book by us "Elementary Flight Dynamics with an Introduction to Bifurcation and Continuation Methods" to be released worldwide by CRC press (US) in September this year.
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