A microscopic positioning device having machine rigidity and being capable of
achieving
nano-order positioning accuracy and a method of compensating tool position and
orientation. A driving unit comprises two piezoelectric elements P1 and
P2 arranged into alignment along an expanding/shrinking direction. Both
ends of the piezoelectric element P1, facing in the expanding/shrinking
direction, are fixed to a base member and a movable member, respectively. The other
piezoelectric element P2 is fixed to the base member only at one end. A
gap L is formed between the piezoelectric element P2 and the movable member.
Where expanding displacement amounts of the piezoelectric elements P1 and
P2 are a1 and a2, respectively, voltage applied to the piezoelectric
elements P1 and P2 is so controlled to satisfy an equation, a1+a2=aL.
It is possible to position the movable member at a position within a maximum stroke
a in the nano-order. The driving units may be arranged in the orthogonal directions,
thereby providing the positioning device with two degrees of freedom, and further
providing six degrees of freedom including rotation axes.
