Patent ID: 8027714

Claim:
An apparatus for controlling the movement of a catheter inside a body of a patient, comprising: a magnetic field source for generating a magnetic field, said magnetic field source comprising: a first coil corresponding to a first magnetic core and a second coil corresponding to a second magnetic core, a third magnetic core corresponding to a third coil, and a fourth magnetic core corresponding to a fourth coil, wherein said first, second, third and fourth cores and coils are arranged in a first semi-spherical symmetry cluster, a fifth coil corresponding to a fifth magnetic core, a sixth coil corresponding to a sixth magnetic core, a seventh coil corresponding to a seventh magnetic core, and an eighth coil corresponding to an eighth magnetic core, wherein said fifth, sixth, seventh and eighth poles and coils are arranged in a second semi-spherical symmetry cluster; and wherein at least said first magnetic core of said first semi-spherical symmetry cluster is moveable with respect to said second magnetic core of said first semi-spherical symmetry cluster and said first magnetic core extends and retracts relative to said first coil; and a servo system controller configured to control extension and retraction of at least said first magnetic core to position said first magnetic core of said first semi-spherical symmetry cluster, said servo system controller configured to receive position data regarding said current position of said distal end of a catheter, said servo system controller further configured to control currents in said first, second, third, fourth, fifth, sixth, seventh and eighth coils to control a movement of a distal end of a catheter to a desired position with torque control fields according to the following equation: B Tq =B XY ·cos(θ) and with force control fields according to the following equation: ⅆ B ⅆ s = ⅆ B XY ⅆ s · cos ⁡ ( ϑ ) where B XY is the field in an XY plane, and θ is angle of spherical rotation of the first, second, third, fourth, fifth, sixth, seventh and eighth coils from the XY plane; said distal end responsive to said magnetic field to move to said desired position.