Right! Now the choice is really whether to have most of the vertical area
behind the Cg or in front of it. If the weather vane had the larger area in
front of the pivot point then it would want to poinb backwards. To be sure,
a cross wind affects the direction of travel......so run in calm winds. Or
get the Cg and the Cp closer together to the reaction is not so pronounced
but when the cat gets sideways or starts to, it will straighten itself up
and head on down the track.
Skip
At 06:16 AM 7/19/04 -0400, Dave Dahlgren wrote:
>your weather vane for all practical purposes has almost zero area in the
>direction that is parallel to the wind. It then has more area behind the
>pivot perpendicular the wind so that it will rotate and always point into
>the wind. So for a slight change in wind direction you get a new heading.
>Are you sure this is desirable behavior? IE. for every change in cross wind
>there is a new intended direction that may or may not be parallel to the
>course.. I think it has more to do with the place tractive force is applied
>in relation to the CG. Think of it as the difference between pushing a car
>and pulling it. Which one is most likely to be self righting in the it would
>rather go straight? This also in my mind means a car with the CG in front of
>the drive wheels and a lot of vertical area behind them is likely to
>'weather vane' IE. change direction with every change is cross wind. John
>Burk are you thinking about this?
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