Apparatus for Measuring Distal Forces on a Working Instrument

Abstract

A robotic catheter manipulator includes a guide catheter including proximal and distal ends and lumen extending there through. A flexible bellows is secured at one end to the proximal end of the guide catheter and at the other end to a seal configured to receive a working catheter. In a loaded state, the working catheter is fixed relative to the seal. A ditherer is operatively connected to the seal for dithering the working catheter relative to the guide catheter when placed therein. The robotic catheter manipulator includes at least one force sensor for measuring the force applied to the working catheter by the ditherer. Force measurements may be translated into an estimated force that is experienced at the distal end of the working catheter which may then be displayed to the physician via a monitor or display.

1 . A robotic catheter manipulator comprising:
 a robotically operated guide catheter including proximal and distal ends and a lumen extending there through;   a flexible bellows having a first end and a second end, the first end being secured to the proximal end of the guide catheter;   a seal secured to the second end of the flexible bellows, the seal configured to receive a working catheter;   a ditherer operatively connected to the seal for dithering the working catheter relative to the guide catheter when placed therein; and   at least one force sensor for measuring the force applied to the working catheter by the ditherer.   
     
     
         2 . The robotic catheter manipulator of  claim 1 , further comprising a robotically operated sheath concentrically arranged about at least a portion of the robotically operated guide catheter. 
     
     
         3 . The robotic catheter manipulator of  claim 1 , wherein the seal comprises a Touhy seal. 
     
     
         4 . The robotic catheter manipulator of  claim 1 , wherein the at least one force sensor comprises two force sensors. 
     
     
         5 . The robotic catheter manipulator of  claim 4 , wherein the ditherer includes a reciprocating carriage containing a pivoting load bearing member, the two force sensors being disposed on the carriage at opposing sides of the load bearing member. 
     
     
         6 . The robotic catheter manipulator of  claim 1 , wherein the two force sensors comprise compression force sensors. 
     
     
         7 . The robotic catheter manipulator of  claim 1 , further comprising a computer configured for calculating an estimated force experienced by a distal end of the working catheter based at least in part on the obtained force measurement for at least one dither cycle. 
     
     
         8 . The robotic catheter manipulator of  claim 7 , further comprising a monitor for displaying the estimated force. 
     
     
         9 . The robotic catheter manipulator of  claim 5 , further comprising a clamp on the load bearing member, the clamp being configured to secure the seal. 
     
     
         10 . The robotic catheter manipulator of  claim 1 , further comprising a clamp for securing a handle of the working catheter. 
     
     
         11 . The robotic catheter manipulator of  claim 1 , further comprising a removable drape for covering at least a portion of the robotically controlled guide catheter. 
     
     
         12 . The robotic catheter manipulator of  claim 1 , the seal comprising an inlet port in communication with the lumen of the guide catheter, the inlet port being configured to receive a pressurized saline solution. 
     
     
         13 . The robotic catheter manipulator of  claim 1 , wherein the robotically controlled guide catheter is connected to a guide catheter splayer. 
     
     
         14 . The robotic catheter manipulator of  claim 2 , wherein the robotically controlled sheath is connected to a sheath splayer. 
     
     
         15 . The robotic catheter manipulator of  claim 5 , wherein the carriage is coupled to a reciprocating lever arm, the lever arm operatively connected at one end thereof to a bearing eccentrically mounted to a pulley, the pulley being driven by a cable.