Remote center of motion robot

Abstract

An embodiment in accordance with the present invention provides a remote center of motion robot. The RCM here is a parallelogram bar type RCM mechanism with a novel joint arrangement. The novel joint arrangement facilitates the mounting of the medical instrument and offers improved clearance relative to the patient. Moreover, the robot was built to guide a bone biopsy cannula, needle, or drill. Even though exact interventional values are unknown, it is expected that the forces exerted laterally on the needle-guide are higher than those encountered for slender needle insertion into soft tissue. For this, the RCM has been built with novel structure to enhance stiffness.

1 . A robot comprising:
 a remote center of motion (RCM) mechanism having a parallelogram structure with non-collinear joints; and   wherein an instrument for use with the robot is aligned between a joint and an RCM point of the RCM mechanism.   
     
     
         2 . The robot of  claim 1 , wherein the parallelogram structure includes redundant parallelogram components. 
     
     
         3 . The robot of  claim 1  further comprising a link and screw mechanism configured for driving the RCM mechanism. 
     
     
         4 . The robot of  claim 1  further comprising the RCM mechanism having a spatial structure. 
     
     
         5 . The robot of  claim 3  further comprising a first set of joints A, A 1 , and A 2  and a second set of joints B, B 1 , and B 2  wherein a first distance between A and A 1  is less than a distance between B and B 1  and a second distance between A 1  and A 2  is less than a second distance between and B 1  and B 2 . 
     
     
         6 . The robot of  claim 1  further comprising a support arm configured to attach to a table and provide rotation about a vertical axis. 
     
     
         7 . The robot of  claim 1  further comprising a needle-guide. 
     
     
         8 . The robot of  claim 7  further comprising the needle-guide having a protruding surface that is positively engaged by a fixture, and a pin of the needle-guide that is latched within the fixture, whereby the needle-guide can be engaged and detached from the fixture through a bag. 
     
     
         9 . The robot of  claim 7  further comprising a ring configured to be placed over a needle, such that the ring allows for a depth of needle insertion to be preset. 
     
     
         10 . The robot of  claim 9  further comprising a device to preset a position of the ring wherein the device comprises a motor to set a depth position and copy it onto the position of the ring. 
     
     
         11 . The robot of  claim 10  further comprising a remote device configured for setting a depth of needle insertion. 
     
     
         12 . The robot of  claim 1  wherein the robot is configured to be safe for use with magnetic resonance (MR). 
     
     
         13 . An actuation module for use with a robot comprising:
 two coaxially aligned motors;   wherein a first of the two coaxially aligned motors is configured to drive a mechanical transmission; and   wherein a second of the two coaxially aligned motors is configured to pass its output through a bore of a first of the two coaxially aligned motors.   
     
     
         14 . The actuation module of  claim 13  further comprising a modular robot structure and a driving mechanism module. 
     
     
         15 . The actuation module of  claim 13  further comprising a kinematic arrangement and a remote center of motion (RCM) mechanism. 
     
     
         16 . The actuation module of  claim 15  further comprising the RCM mechanism being driven by a link and screw mechanism. 
     
     
         17 . The actuation module of  claim 13  further comprising a harmonic drive. 
     
     
         18 . The actuation module of  claim 13  further comprising an adjustable mounting system. 
     
     
         19 . The actuation module of  claim 18  wherein the adjustable mounting system is configured to couple to an MRI table. 
     
     
         20 . A device comprising:
 a needle-guide having a protruding surface;   a fixture that positively engages the protruding surface of the needle-guide; and   a pin of the needle-guide that is latched within the fixture, whereby the needle-guide can be engaged and detached from the fixture through a bag.