SYSTEM AND APPARATUS FOR MEASURING DISTAL FORCES ON A WORKING INSTRUMENT

摘要

An apparatus for positioning a distal end (34) of a working instrument (30) at a body site such as a lumen includes a guide instrument (4) and a working instrument (30) disposed within a lumen (8) of the guide instrument (4). A reciprocating ditherer (50) is mechanically coupled to the working instrument (30) and proximal region (35) of the guide instrument (30) and configured for moving the working instrument (30) relative to the guide instrument (4). The apparatus includes at least one load cell (200) containing a force sensor (204) configured for measuring the forces experienced at a distal end (34) of the working instrument (30). A processor (118) is configured to calculate an estimated force at the distal end (34) of the working instrument (30) based at least in part on the comparison of an output of the at least one load cell (200) force sensor (204) during zero or no load conditions and an output of the force sensor (204) during load conditions.