How to evaluate the bias stability and angle random walk performance of Digital Gyroscope?
Publish Time: 2024-07-15
Bias stability and angle random walk are two key indicators when evaluating the performance of Digital Gyroscope.
Bias stability reflects the change of the mean value of the gyroscope output over time when there is no input angular velocity. In order to evaluate this performance, long-term static testing is usually required. The gyroscope is placed in a stable environment, its output data is recorded, and it is continuously monitored for a period of time (such as hours or even days). By statistically analyzing these data, the range of change and drift rate of the mean are calculated to determine the bias stability.
Angle random walk describes the short-term uncertainty of the gyroscope output angle. The evaluation of this performance usually relies on the analysis of the gyroscope output noise. The Allan variance analysis method can be used to process the high-frequency data collected in a short period of time. Allan variance can reveal the characteristics of gyroscope noise at different time scales, thereby determining the angle random walk coefficient.
In actual testing, the control of environmental factors is crucial. Temperature changes, vibrations, and electromagnetic interference may affect the accuracy of test results. Therefore, the test is usually carried out in a constant temperature, vibration-free and electromagnetically shielded environment.
In addition, in order to obtain more reliable evaluation results, it is necessary to repeat the test many times and sample different batches of products. For example, in the navigation system, if the zero bias stability of the Digital Gyroscope is poor, it will lead to a large deviation in the position estimation after a long navigation. And the poor performance of the angle random walk will cause the system to have a large jitter and uncertainty in the attitude solution in a short time.
By accurately evaluating the zero bias stability and angle random walk performance of the Digital Gyroscope, it can provide an important basis for its selection and use in various applications. For example, for high-precision satellite navigation, a gyroscope with excellent zero bias stability and angle random walk performance is required; while for some consumer-grade electronic devices, slightly worse performance may be tolerated to a certain extent, but it still needs to meet basic application requirements.
In short, scientifically and accurately evaluating the zero bias stability and angle random walk performance of the Digital Gyroscope is of great significance to ensure its effective application in different fields.
