Abstract
Inertial measurement units (IMUs) have been widely used to provide accurate location and movement measurement solutions, along with the advances of modern manufacturing technologies. The scale factors of accelerometers and gyroscopes are linear when the range of the sensors are reasonably small, but the factor becomes nonlinear when the range gets much bigger. Based on this observation, this article presents a calibration method for low-cost IMU by effectively deriving the nonlinear scale factors of the sensors. Two motion patterns of the sensor on a rigid object are moved to collect data for calibration: One motion pattern is to upcast and rotate the rigid object, and another pattern is to place the rigid object on a stable base in different attitudes. The rotation motion produces centripetal and Coriolis force, which increases the measurement range of accelerometers. Four cost functions with different weight factors and two sets of data are utilized to optimize the IMU parameters. The weight factor comes from derived formula with input values which are the variance of the noise of the sampled data. The proposed approach was validated and evaluated on both synthetic and real-world data sets, and the experimental results demonstrated the superiority of the proposed approach in improving the accuracy of IMU for long-range use. In particular, the errors of acceleration and angular velocity led by our algorithm are significantly smaller than those resulted from the existing approaches using the same testing data sets, demonstrating a remarkable improvement of 64.12% and 47.90%, respectively.
Highlights
A N Inertial Measurement Unit (IMU) is often used to detect the acceleration and angular velocity of a moving object
Thanks to the advances of microelectrophoretical techniques, inertial sensors can be manufactured as microelectrophoretical system (MEMS), with considerably low cost, but with increased
1) Centripetal acceleration: The centrifugal force of IMU is illustrated in Fig. 1-a, where ω represents the angular velocity; P is the center of gravity of the rigid body; O is the origin of sensor frame
Summary
A N Inertial Measurement Unit (IMU) is often used to detect the acceleration and angular velocity of a moving object. This paper proposes a method for obtaining nonlinear scale factors of a sensor without using high-cost instruments, to address the aforementioned challenge. In this method, the IMU is affixed to the surface of an object that cannot be deformed. A filter algorithm in this approach is designed to extract useful information from the raw data With these data, all initial parameters of the IMU sensor are placed into four cost functions. The main contributions of this paper are summarised as follows: (1) A method is proposed to obtain IMU calibration parameters that include the nonlinear scale factor.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
