[ODE] prescribed motion for one body and collision with another body

[Martin C. Martin]

 > -  ODE can not handle a collision between bodies if one of the bodies has
 > prescribed motion in form of position as a function of time?

Sure it can.  Why couldn't it?

 > - the only available solution is to define the prescribed motion in 
form of
 > speed/time and to use the desired motor velocity capability  ?

If the body with the "prescribed motion" is moving slowly, you can give 
it a dGeom but not a dBody, and simply change its position every time.