Measuring position and orientation using magnetic fields

A system for determining the location of a remote device comprising:

• a plurality of transducers operable to determine the location of a remote device in an operation zone, the transducers are electromagnetic and include one or more device transducers and one or more locator transducers;
• a remote device for placement in an operation zone, the remote device having the one or more device transducers;
• a locator operable away from, but within an interaction distance from, the remote device, the locator having the one or more locator transducers;
• a driver connected to sequentially energize one or more of the device transducers and/or the locator transducers;
• a processor operably connected to receive sensor signals from one or more of the transducers, each sensor signal on a given one of the transducers depending on the energizing of another of the transducers, the processor configured to iteratively determine at least two location parameters of the remote device in the patient using a plurality of equations of exact magnetic field coupling that remain valid for zero separation distance from the energized transducer to the transducer generating the sensor signal for validity;
• and
• wherein each of the transducers generates and/or senses an electromagnetic field.

A method of determining the location of a remote device comprising the steps of:

• using a system having a plurality of coils operable to determine the location of a remote device, the coils including one or more device coils and one or more locator coils;
• placing the remote device in an operation zone, the remote device having the one or more device coils;
• placing a locator away from, but within an interaction distance from, the remote device, the locator having the one or more locator coils;
• sequentially energizing one or more of the device coils and/or the locator coils;
• generating sensor signals from one or more of the coils, each sensor signal on a given one of the coils depending on the energizing of another of the coils;
• supplying the sensor signals to a processor;
• and
• determining by operation of the processor at least two location parameters of the remote device using a plurality of equations that remain valid for zero separation distance from the energized coil to the coil generating the sensor signal for validity;
• and
• wherein the system is a medical system used to treat a patient, the remote device is a medical device and the operation zone is within a patient.

A method of determining the location of a remote device comprising the steps of:

• using a system having a plurality of coils operable to determine the location of a remote device, the electromagnetic transducers including one or more device electromagnetic transducers and one or more locator electromagnetic transducers;
• placing the remote device in an operation zone, the remote device having the one or more device electromagnetic transducers;
• placing a locator away from, but within an interaction distance from, the remote device, the locator having the one or more locator electromagnetic transducers;
• sequentially energizing one or more of the device electromagnetic transducers and/or the locator electromagnetic transducers;
• generating sensor signals from one or more of the electromagnetic transducers, each sensor signal on a given one of the electromagnetic transducers depending on the energizing of another of the electromagnetic transducers;
• and
• supplying the sensor signals to a processor, the processor determining at least two location parameters of the remote device using a plurality of equations that remain valid for zero separation distance from the energized transducers to the transducers generating the sensor signal for validity;
• and
• wherein each of the electromagnetic transducers generates and/or senses an electromagnetic field.