Roll detection and six degrees of freedom sensor assembly

A medical device comprising:

• a sensor assembly comprising:
• a hollow core extending along an axis and having an outer surface;
• and
• a coil extending along and disposed about said axis, the coil comprising a first portion, disposed on said core outer surface, comprising at least one first loop about the full circumference of said axis, said at least one first loop defining a first winding angle, and a second portion, electrically coupled with said first portion, comprising at least one second loop about the full circumference of said axis, said at least one second loop defining a second winding angle that is different from said first winding angle, wherein at least a part of said second portion overlaps at least a part of said first portion;
• wherein at least one of said first winding angle and said second winding angle is substantially nonzero relative to a line that is perpendicular to said axis;
• whereby said coil is configured to produce a signal responsive to an applied magnetic field indicative of at least the roll of said coil about said axis.

An elongate medical device comprising:

• an elongate shaft defining a longitudinal shaft axis;
• and
• a sensor assembly disposed within said elongate shaft and comprising:
• a core extending along a core axis that is parallel with said longitudinal shaft axis and having an outer surface;
• and
• a coil extending along and disposed about said core axis, the coil comprising a first portion, disposed on said core outer surface, comprising at least one first loop about the full circumference of said axis, said at least one first loop defining a first winding angle, and a second portion, comprising at least one second loop about the full circumference of said axis, said at least one second loop electrically coupled with said first portion, defining a second winding angle that is different from said first winding angle;
• wherein at least one of said first winding angle and said second winding angle is substantially nonzero relative to a line that is perpendicular to said core axis and wherein at least a part of said second portion overlaps at least a part of said first portion.