Patent ID: 8909500
Filing Date: 2014-12-09
Classification: A61B

Abstract:
1. A method of measuring an angle (α) between a first member and a second member under dynamic conditions, comprising: connecting a first acceleration sensor to the first member and connecting a second acceleration sensor to the second member; connecting an angle measuring device to the first and the second members, wherein the angle measuring device is configured to measure, under static and dynamic conditions, a measuring value dependent on the angle (α) between the first and second members; wherein the angle measuring device is a flexible goniometer which measures the angle between the members directly; under dynamic conditions, measuring the angle (α) between the first and second members by the angle measuring device; under static conditions, measuring an angle (αstatic) between the first and second members by the angle measuring device; measuring the inclination angle of the first member using the first acceleration sensor and the inclination angle of the second member using the second acceleration sensor and calculating an angle (αstatic′) between the first and second members; calculating a ratio between the angle (αstatic) between the first and second members as measured by the angle measuring device and the angle (αstatic′) between the first and second members as calculated from the inclination angle of the first member as measured by the first acceleration sensor and the inclination angle of the second member as measured by the second acceleration sensor; calculating an error correction factor from said ratio between the angle (αstatic) between the first and second members as measured by the angle measuring device and the angle (αstatic′) between the first and second members as calculated from the inclination angle of the first member as measured by the first acceleration sensor and the inclination angle of the second member as measured by the second acceleration sensor; and applying said error correction factor to future and/or previous measurements of the angle (α) between the first and second members by the angle measuring device.