Most needle robots orient a needle guide and insertion is then performed manually. But actuated needle drivers could have additional features which may exceed manual capabilities. The RND is a fully actuated driver for needle insertion, spinning, release, and force measurement. This is perhaps the most complex, feature rich needle driver reported (2008).
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A novel kinematic design used for inserting the needle, which creates the translation motion with a mechanism of rotary joints. This allowed for a compact design, so that the driver is less tall than the needle.
Beside its actuated needle insertion mechanism, the RND is also capable of spinning the needle, so that the needle is advanced in a drill-like motion. To engage the needle, standard needles are placed in a custom adapter fitted with a gear.
The RND supports the needle from its head, and provides an additional needle support guide in close proximity of the skin entry point. This is similar to holding the needle with two finger-like grippers, one from its head and one from its barrel next to the skin. The top one pushes the needle in and out, while the lower holds the guide to support the direction of the needle as close as possible to the skin. The guide or needle nozzle also encases the sharp needle point before insertion to protect the patient and personnel. Both grippers can simultaneously release the needle automatically.
Finally, the new driver is also equipped with a set of force sensors to measure the interaction of the nozzle with the patient and the force of needle insertion. These can be used either with a haptic interface to reproduce the interaction of the physician in handling the needle, or to provide additional information that is not typically used in the manual case, such as respiratory motion tracking.