This paper present a wavelet-based procedure for the filtering of IMU data both during the alignment and the navigation that automatically changes the cut-off parameter of the multi-resolution analysis. During the alignment procedure a "hard" filtering can in fact be used to evaluate the initial attitude angles, with a cut-off frequency close to 0.5 Hz, whereas a "soft" filtering during the navigation can be used to preserve the information on the accelerations and angular velocity measurements of the sensors, by setting a more elevated cut-off frequency. The proposed de-noising method was applied to a low-cost tactical grade Inertial Measurement Units (Crossbow IMU 700-CA and IMU 400-CC) and an improvement in the signal-to-noise ratio and consequently in the evaluation of the navigation parameters was obtained.
[1]
N. El-Sheimy,et al.
Wavelet de-noising for IMU alignment
,
2004,
IEEE Aerospace and Electronic Systems Magazine.
[2]
Mohinder S. Grewal,et al.
Global Positioning Systems, Inertial Navigation, and Integration
,
2000
.
[3]
C. Porporato,et al.
Italian low cost GNSS/INS system suitable for mobile mapping
,
2009,
IEEE Aerospace and Electronic Systems Magazine.
[4]
A. Grossmann,et al.
Cycle-octave and related transforms in seismic signal analysis
,
1984
.
[5]
George T Schmidt,et al.
INS/GPS Technology Trends
,
2010
.
[6]
Sameh Nassar,et al.
Improving the Inertial Navigation System (INS) error model for INS and INS/DGPS applications
,
2003
.