Abstract: A calibration method and also a calibration device are proposed to enable a spatial position and/or orientation of a surgical referencing unit of a surgical navigation system fitted with at least one inertial sensor to be specified in relation to a spatial coordinate system.

Abstract: A device for detecting a fault current in an electronic apparatus has a first and at least one second electric conductor, the first electric conductor carrying a first electric potential and the at least one second electric conductor carrying a second electric potential. The device is characterized by the fact that an electric sensing conductor having a fixed electric rest potential whose value lies between the first and the at least second electric potential is situated between the electric conductors.

Abstract: A calibration method and also a calibration device are proposed to enable a spatial position and/or orientation of a surgical referencing unit of a surgical navigation system fitted with at least one inertial sensor to be specified in relation to a spatial coordinate system.

Abstract: A device for detecting a fault current in an electronic apparatus has a first and at least one second electric conductor, the first electric conductor carrying a first electric potential and the at least one second electric conductor carrying a second electric potential. The device is characterized by the fact that an electric sensing conductor having a fixed electric rest potential whose value lies between the first and the at least second electric potential is situated between the electric conductors.

Abstract: An apparatus for recording the contour of a surface of a body is provided in accordance with the present invention. The apparatus comprises a carrier on which at least one distance measuring element is disposed. The at least one distance measuring element is capable of determining a distance between the carrier and a location on the surface of the body. A navigation system with marking elements is provided. The marking elements are fixable on the carrier and on the body, such that positional data regarding the position of the body and the carrier can be determined by the navigation system. A data-processing device device is also provided, which is adapted to calculate the contour of the surface from the positional data of the body and of the carrier and the distance measurements of the at least one distance measuring element.

Abstract: In order to improve the precision of determining the articulation point with a method for determining an articulation point of two bones, which are connected by a joint and are connected to pivot relative to one another around at least two non-parallel rotational axes, wherein the two bones are moved relative to one another, measured values describing the movement of a point of a bone in a reference system of the other bone are recorded, a rotational axis describing the movement as rotation is determined from these measured values for a plurality of parts of the path or respectively for one of a plurality of consecutively recorded paths, it is proposed that the deviation in orientation is calculated for the differently oriented rotational axes determined in this way and from the differently oriented rotational axes an articulation point is calculated only when the deviation in orientation of the rotational axes exceeds a specific value.

Abstract: An apparatus for recording the contour of a surface of a body is provided in accordance with the present invention. The apparatus comprises a carrier on which at least one distance measuring element is disposed. The at least one distance measuring element is capable of determining a distance between the carrier and a location on the surface of the body. A navigation system with marking elements is provided. The marking elements are fixable on the carrier and on the body, such that positional data regarding the position of the body and the carrier can be determined by the navigation system. A data-processing device device is also provided, which is adapted to calculate the contour of the surface from the positional data of the body and of the carrier and the distance measurements of the at least one distance measuring element.