Re: [Jsbsim-devel] Multi-body modeling

[David C. <dav...@co...>]

There was a discussion here a few years ago about setting up a "master/slave" capability for JSBSim, wherein an instance of the FDM could be slaved to some external source of position/orientation/velocity (POV).  The discussion was started as a possible solution to the problem of how one models the launching of an X-15 from a mothership.

The X-15 FDM, while in slaved mode, would still be iterating in order to keep a propulsion system, atmosphere, etc. running, as well as making sure that all the derived properties of the vehicle state are populated with reasonable numbers.  When launched, the X-15 would start providing its own POV, hopefully without any initial transients.

The external source of POV could be anything.  Another instance of FGFDMExec, a fixed location for modeling a launch tower/rail, another app (i.e. FlightGear).

The benefit of this over a multi-body solution is that the slaved object and master object aren't communicating over some elastic structure using forces.

Dave