Andy Ross <[EMAIL PROTECTED]> said: > Jim Wilson wrote: > > Andy Ross wrote: > > > The FDMs already take the c.g. into consideration. If a stopped > > > aircraft rotates (about the c.g, of couse), you will see the > > > coordinate origin moving. > > > > Well this might be useful to the 3D model. The effect probably isn't > > all that noticable compared to what we have now, but a real plane > > would pitch and roll about it's cg rather than the fixed "origin" as > > defined in a 3D model, wouldn't it? > > It would indeed. And it already does. Again, the rigid body magic > required to move the coordinate origin appropriately for a given > rotation about the center of gravity is the FDM's job. They already > do this; all the rest of the system has to do is draw the origin at > the right place. > > Once more: there's no error. Things are taken care of for you by the > physics code in the FDMs. >
Ok, so are you saying that the lon/lat/alt values that the fdm outputs are at the origin already adjusted for cg? If so then how would that affect the axis of say pitch rotation on the c172 model? It's origin is at the firewall and the pitch rotation is always on the access that intersects there. Should we be doing something different? Best, Jim _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
