Rotational support for an elongate member

Abstract

Various exemplary drive apparatuses and associated methods are disclosed for driving an elongated member, e.g., a guidewire or catheter. An exemplary drive apparatus for driving an elongated member may include a rotational component configured to apply a torque to the elongated member, where the rotational component is positioned a first distance away from an insertion site along the elongated member. The drive apparatus may further include a rotational support configured to apply an assistance torque to the elongated member. The rotational support may be positioned a second distance from the rotational component along the elongated member that is larger than the first distance.

What is claimed is: 
     
         1 . A method of robotically driving an elongate member, the method comprising:
 applying a first torque to the elongate member with a robotically-controlled rotational component positioned a first distance away from an insertion site along the elongate member; and   applying a second torque to the elongate member with a robotically-controlled rotational support positioned a second distance away from the insertion site along the elongate member, wherein the rotational support is infinitely rotatable, and wherein the second distance is longer than the first distance.   
     
     
         2 . The method of  claim 1 , wherein applying the first torque and the second torque turns a first portion of the elongate member relative to a second portion of the elongate member such that the first portion is not aligned with the insertion site along an insertion axis and the second portion is aligned with the insertion site along the insertion axis. 
     
     
         3 . The method of  claim 2 , further comprising restraining the first portion of the elongate member in a turned orientation by the rotational component and the rotational support. 
     
     
         4 . The method of  claim 2 , wherein the first portion of the elongate member is turned about 180 degrees relative to the second portion. 
     
     
         5 . The method of  claim 1 , wherein the second torque is greater than the first torque. 
     
     
         6 . The method of  claim 1 , wherein the second torque is a coarse torque adjustment and the first torque is a fine torque adjustment. 
     
     
         7 . The method of  claim 1 , further comprising:
 adjusting the second torque in a first increment; and   adjusting the first torque in a second increment smaller than the first increment.   
     
     
         8 . The method of  claim 1 , further comprising anchoring an end of the elongate member with the rotational support. 
     
     
         9 . The method of  claim 8 , wherein anchoring the end of the elongate member includes deforming the elongate member adjacent the end. 
     
     
         10 . The method of  claim 1 , further comprising receiving an end of the elongate member within a sleeve extending from the end of the elongate member along a length of the elongate member. 
     
     
         11 . The method of  claim 1 , wherein a portion of the elongate member is positioned between the rotational component and the rotational support. 
     
     
         12 . The method of  claim 11 , wherein the portion of the elongate member positioned between the rotational component and the rotational support changes length during insertion and retraction of the elongate member without relative movement between the rotational component and rotational support. 
     
     
         13 . The method of  claim 1 , wherein robotically driving the elongate member comprises robotically driving a guidewire. 
     
     
         14 . The method of  claim 13 , wherein the rotational support applies the second torque to the guidewire while the guidewire is inserted coaxially into a catheter. 
     
     
         15 . The method of  claim 1 , further comprising selectively releasing a portion of the second torque with the rotational component. 
     
     
         16 . The method of  claim 1 , wherein an end of the elongate member is anchored to the rotational support. 
     
     
         17 . The method of  claim 1 , further comprising applying a force to the elongate member with an intermediate member located between the rotational support and the rotational component to restrict twisting of the elongate member.