Passive Arm with Dynamic Constraints (PADyC)

Medical robotics faces the need for interacting with a clinical expert and offering a perfect safety for both the medical staff and the patient. We proposed a new concept, the « synergistic robot » also called « hands on robot » by other authors which carries the instrument held by the clinician and whose function is to limit the instrument motions with respect to a pre-defined surgical plan. This allows reaching a target position, to follow a trajectory or to stay inside an authorized region. The mechanical architecture implementing programmable constraints is passive (the robot cannot move by itself and is actuated by the user) and integrates a patented mechanism based on clutchable freewheels.

References :
O. Schneider, J. Troccaz. A Six Degree of Freedom Passive Arm with Dynamic Constraints (PADyC) for Cardiac Surgery Application : Preliminary Experiments. Computer-Aided Surgery, special issue on medical robotics, 6(6), pp340-51, 2001 (PDF)

J. Troccaz and Y. Delnondedieu. Semi-active guiding systems in surgery. A two-dof prototype of the passive arm with dynamic constraints (PADyC). Mechatronics, 6(4):399—421, June 1996.

Collaborations : Praxim, Alpes Instruments

Status : protected by several patents. 2 PhDs. Several working protptypes (3 axes version for feasability, 6 axes version for application to pericardial punctures, (usable for other applications), 2 axes light version for knee surgery. Experiments on phantoms. On going work on the last prototype.

More information : section « Scientifique/PADyC » (in french)

Contact :

Laboratoire TIMC-IMAG, Domaine de la Merci, 38706 La Tronche Cedex

Grenoble INP
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