Effectiveness of Variable-Gain Kalman Filter Based on Angle Error Calculated from Acceleration Signals in Lower Limb Angle Measurement with Inertial Sensors

Figure 1

Block diagrams of the angle calculation methods using Kalman filter tested in this paper.

(a)   Fixed Kalman gain method

(b) Variable-Kalman-gain method based on acceleration magnitude

(c) Variable-Kalman-gain method based on angle error