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A.Wendy January 21, 2013 02:51

OF 1.6 extend. GGI - rotation around two axis - C++ newbie needs help
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Hi everybody,

i have a problem and i hope you can help me.
i am planing to simulate an gyro-copter including the auto rotation.
i was able to implement some rigid body movement into the mixerggi library and can simulate a rotation around one fixed axis. but i also want to simulate the flapping hinge. for that i need to make a rotation around a second axis.
i know what i have to implement but i dont know how.

the plan is the following:
reading out he forces using forces library <- works
recalculate an ne rpm for rotation <- works
rotate the rotor around z-axis <- works
change the rotation axis for flapping hinge <- does not work (see below)
rotate rotor for flapping hinge <- should work
change rotation axis back to z-axis and start to next time step.

here to the problem with the rotation for the flapping hinge:
when the rotor is rotating around the z-axis the coordinate system for the flapping hinge will change by each time step. so i have to compute this axis manually. i think i can do this. but i can not store these data in the variable of the mixerGgi script.
the variables (classes) are:

i am able to change the origin but not the axis. has anyone an idea to solve this problem?

here is the declaration:
//- Return coordinate system
const coordinateSystem& cs() const
return csPtr_();

how can i change it? why can i change the origin but not the axis? both have the same declaration or?

i added the c-file and header.

Best wishes


A.Wendy February 4, 2013 09:05


nobody got an idea?

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