[ODE] Moving joints that are attached to the static environment

[Frederic Ferland]

Hopefully there is a simple solution to the problem I'm facing...  I have 
modeled a bridge with several individual planks attached by ball 
joints.  Each pair of plank is attached together with two joints, except 
for the two planks at each end of the bridge, which are attached to the 
static environment.  This creates a flat bridge like this (as seen from the 
side):

   x---------o---------o---------o---------o---------o---------x

What I would like to do is be able to move the leftmost joint (the one 
attached to the static environment) to the right so that the bridge bends 
like this:
(ugly ASCII art :) )


x                                                                   x
     \                                                           /
          o                                                o
                \                                      /
                      o  --------- o --------- o


I haven't tried, but I'm pretty sure that if I simply call the 
dJointSetBallAnchor( ) function with the new position, I won't get the 
desired result.  How can I achieve the desired result then?

Thanks for any idea!