Apparatus for measuring the locational and attitudinal change of a rigid body in space

An apparatus for measuring the location and attitude, as well as, locational and attitudinal changes of a jaw of a patient, comprising:

• transmission system means for generating three different alternating magnetic fields comprising three current-permeated elements arranged in a U-shaped configuration in one plane and supplied respectively with three different respective operating frequencies by an alternating current generator, each of said current-permeated elements comprising a plurality of individual conductors surrounded by an enveloping tube the ends of said conductors being electrically connected to one another, each enveloping tube being attached to means for securing the current-permeated elements in a predetermined fixed position in relation to a patient's head, said current-permeated conductors each having a length which roughly corresponds to the width of the jaw of the patient;
• reception system having three reception elements arranged on a retaining part corresponding to a dental arch attachable to the jaw of a patient, said three reception elements arranged at a predetermined, fixed spacing from one another for measurement of lower jaw movement of said patient, said reception elements lying in one plane and their arrangement forming the corners of a equilateral triangle, thereby defining three predetermined measuring points, each of said three reception elements having at least three magnetic field sensors for receiving said magnetic fields generated by said transmission system, said magnetic field sensors being coils which are arranged on a coil bobbin of non-ferromagnetic material perpendicular to one another;
• and
• evaluation electronic means connected to said reception system for receiving signals from said coils which are representative of said three different alternating magnetic fields;
• wherein said evaluation electronics include means for converting said signals into quantities corresponding to positions of said three measuring points with respect to said current-permeated elements.

An apparatus for measuring the location and attitude, as well as, locational and attitudinal changes of a jaw of a patient, comprising:

• transmission system means for generating three different alternating magnetic fields comprising three current-permeated elements arranged in a U-shaped configuration and respectively supplied with three different respective operating frequencies by an alternating current generator, said current-permeated elements being arranged in one plane, each element comprising a plurality of individual conductors which are surrounded by an eveloping tube connected to means for securing the current-permeated elements in a predetermined fixed position in relation to a patient's head;
• reception system means having three reception elements attachable to the lower jaw of the patient at predetermined measuring points in one plane in an arrangement forming the corner points of an equilateral triangle, each of said reception elements having three magnetic field sensor means for receiving said magnetic fields generated by the transmission system, said magnetic field sensors comprising coils which are arranged on a coil bobbin of non-ferromagnetic material in an orientation perpendicular to one another;
• and
• evaluation electronics means connected to said reception elements for receiving signals from said coils representative of said three different alternating magnetic fields, said evaluation electronics means including means for separating each received signal through frequency filters, and for issuing signal quantities corresponding to the relative positions of the reception elements with respect to the respective current-permeated elements from the separated signals.