Accelerometer Calibration and Dynamic Bias and Gravity Estimation: Analysis, Design, and Experimental Evaluation

• Published in: IEEE transactions on control systems technology 2011-09, Vol.19 (5), p.1128-1137
• Main Authors: Batista, P., Silvestre, C., Oliveira, P., Cardeira, B.
• Format: Article
• Language: English
• Subjects: Accelerometers; Algorithms; Applied sciences; Bias; Calibration; Computer science; control theory; systems; Control system synthesis; Control theory. Systems; Cross coupling; Exact sciences and technology; Filtering; Gravitation; Gravity; Kalman filters; Measurements common to several branches of physics and astronomy; Metrology, measurements and laboratory procedures; Modelling and identification; Navigation; Nonlinear dynamics; Physics; Sensor systems and applications; Velocity, acceleration and rotation
• ISSN: 1063-6536; 1558-0865
• DOI: 10.1109/TCST.2010.2076321

Tri-axial linear accelerometers are key components in a great variety of applications and, in particular, in navigation systems. Nonidealities such as scale factors, cross coupling, bias, and other higher-order nonlinearities affect the output of this sensor, leading, in general, to prohibitive errors. On the other hand, these coefficients are often slowly time-varying, which renders offline calibration less effective. One such coefficient that usually varies greatly over time and between power-ons is the bias. This paper details the calibration of an accelerometer unit and presents also a dynamic filtering solution for the bias, which also includes the estimation of the gravity in body-fixed coordinates. Simulation and experimental results obtained with a motion rate table are presented and discussed to illustrate the performance of the proposed algorithms.