Physical prototype of 6-DOF piezoelectric actuated needle placement robot consisting of needle driver module and Cartesian gross positioning module. The needle driver module provides 8cm insertion stroke, 5cm stylet retraction stroke and 40 revolutions per minute rotation speed. The Cartesian gross positioning module provides 8cm axial motion, 3cm elevation and 4cm lateral motion. (Right) The robot prototype in the bore of a 3T MRI scanner with a phantom.