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Register a new userAn Efficient Autocalibration Method for Triaxial Gyroscope without External Device
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Gyroscopes are widely used in various field. The instability of the low-cost gyroscopes makes them need to be calibrated on every boot. To meet the requirement of frequency calibration, finding an efficient in-field calibration method is essential. This paper proposes a fast calibration method that does not require any external equipment. We use the manual rotation angle as a calibration reference and linearize the calibration model. On the basis of this model, a G-optimal experimental design scheme is proposed, which can get enough calibration information with the least number of experiments. The simulations indicate that the calibration error is relatively low, and the results are unbiased. We empirically validate the effectiveness of the proposed method on two commonly used low-cost gyroscope and achieve real-time calibration on a low-energy microcontroller. We validate the proposed method by comparing the above method with the conventional turntable method. The experiment result shows that the error between these two methods is less than $pm3 times 10^{-2}$ and the calibration process takes less than 30 seconds. This method might have a practical implication for low-cost gyroscope calibration.
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This paper presents an efficient servomotor-aided calibration method for the triaxial gyroscope. The entire calibration process only requires approximately one minute, and does not require high-precision equipment. This method is based on the idea that the measurement of the gyroscope should be equal to the rotation speed of the servomotor. A six-observation experimental design is proposed to minimize the maximum variance of the estimated scale factors and biases. In addition, a fast converging recursive linear least square estimation method is presented to reduce computational complexity. The simulation results reflect the robustness of the calibration method under normal and extreme conditions. We experimentally demonstrate the feasibility of the proposed method on a robot arm, and implement the method on a microcontroller. We verify the calibration results of the proposed method by comparing with a traditional turntable approach, and the experiment indicates that the results of these two methods are comparable. By comparing the calibrated low-cost gyroscope reading with the reading from a high-precision gyroscope, we can conclude that our method significantly increases the gyroscopes accuracy.
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