Analyzing 3DKneeKinematics UsingAccelerometers, Gyroscopes andMagnetometers
Syoji Kobashi, Masayoshi Yagi, Katsuya Kondo, Shinichi Yoshiya · 2007
Kneekinematics hasbeeninvestigated to sensoralthough their estimation accuracy areinferior toX- diagnose subjects withinjured anterior cruciate ligament rayfluoroscopy imaging systems because their sesorsor markerts areattached onthehumanskin. Amongthem, (ACL). Dejnabadi etal.presented akinematics analysis IMU sensorsystem hasadvantages that themeasurement methodusingacespace isunlimited andthetemporal resolution ishigh. In cananalyze thekneekinematics without accumulation of contrast, theoptical motion system limits thespaceinto errors, itestimates only knee flexionlextensio n angle. Thus,about acubeof2m wheretracing markers arecaptured, this paperproposed anewmethod that canestimate all andalsothemeasuremet spaceelectromagnetic device is kneejoint angles, flexionlextension, internal external about acubeof1m where themagnetfield canbereached. rotation, andvaruslvalgus angles. Itisenabled by introducing earth magnetisms intoDejnabadi's method. Theproposed methodwasvalidated byapplying the Tn ta.peetdagi nlsssse sn Theproposed methooda subject.vanid,theestmate db angg wee gyroscopes (6). Inthesystem, gyroscopes wereattached on proosdmthdasujh ematans w theskin surface ofthethigh andshank regions. Kneejoint numerically evaluated bycomparing theresults with angle werederived fromangular velocities. However, knee optical motion system. jointangledrifted. To solvethisdrift, thesystem automatically reset angle using gait cycle. Therefore, the