Study On Dithered-bias Ring Laser Gyro Error Over Lock-in

The mechanically dithered ring laser gyro (MDRLG) has many advantages, such aslow cost, long life time, high reliability, large dynamic range and so on．Themechanically dithered ring laser gyro (MDRLG) has been firstly used in practice andwidely used in measurement all over the world.In the manufacture of Ring Laser Gyro,how to reduce or remove the Lock—ineffect is one of the key problems,which restricts the development of Ring Laser Gyro．To build up RLG error modeling of lock-in effect, and calculate the error with thegiven parameters has been the key point which people pay attention to. Some issuesabout MDRLG have been mainly studied in this paper, such as deriving errorexpression from time domain and frequency domain, reducing lock-in effect in activeresonant cavity, carrying on phase difference equation simulation of laser gyro lock-ineffect.In this paper, several bias techniques of the Ring Laser Gyroscope have beendiscussed. Three main errors-bias, changes of scale factor and lock-in effect have alsobeen discussed, the causes of these errors have been analyzed thoroughly.This paper particularly analyzes and studies the Ring Laser Gyroscope dither—biastechnique by studying the characteristic in time domain when passing across thelock—in and the characteristics of input and output in frequency domain. Error modelhas been established and detailed analysis has been carried out. Finally, theconclusion-some parameters having effects on the MDRLG error is given.