I’m building a rigid body simulation of a sailboat that’s floating on the ocean.  i want the shutters on the boat to swing with the boats movement.  i created a hinge constraint and parented it to the boat.  when the hinge is at an angle, the rigid body rotates out of place.  i’ve discovered that hinge constraints always lose precision at an angle. (see attached file “boat example.mb")

as an example: (see attached file “hinge example.mb") create a cube. add a hinge and move it to the edge. add gravity. group all together and rotate to random inclined position.  the cube will swing but will also slowly rotate on the axis as though it were a nail constraint.

the only work around i could find was to create a pin constraint between the shutter and a passive rigid body which is then parented to the boat.  if i change the constraint type to “hinge” in the attribute editor, the rig works as expected.  i have to lower the solver steps or else it will also lose it’s angle after awhile.

are hinge constraints only made to work on the primary three axis?  and is it not possible to animate the location/rotation of a hinge?

I am building a sail boat using nDynamics, nCloth and nConstraints (Maya2010)
All really nice to use.
see link below.

...my sail flaps in the breeze quite happily and reacts to boat motion.
Your shutters could be stiff cloth.
Have you considered this approach? I am having some success.
My problem is to use the force to propel the boat in the right direction,
That was hard enough in real world sailing!

look for nCloth with fast moving object.
http://resources.autodesk.com/med/Autodesk_Maya/How_Tos

Never parent a dynamic constraint. You must constrain a rigid body to another rigid body. What’s misleading is that you can create a constraint for an object when you have only one object selected and it will work somewhat, but it will not work correctly, and you’ll see that as soon as you try to animate the parent transform.