Dynamic Characteristics Analysis Of The Inertial Navigation Bearing

As an important element of the inertial navigation system.The fluctuation of the friction torque and wear performance of inertial navigation bearing directly affect the measurement accuracy of the gyroscope,and then affecting the positioning performance of navigation system.At present,the research of inertial navigation bearing mainly focuses on the stiffness of bearing,fatigue life,dynamic characteristics of cage and so on.There is a few studies on friction and wear.Therefore,it is of great theoretical value to analyze the dynamic characteristics of the inertial navigation bearing with the aim of the fluctuation of the friction torque and the wear life of the bearing.In order to study the dynamic characteristics of inertial navigation bearing,the dynamic differential equations of inertial navigation bearing and the mathematical model of friction torque are established based on the dynamic theory of rolling bearing.The dynamic differential equations of inertial navigation bearing are solved by GSTIFF.The interaction subroutine between the components of the bearing is written by using the programming language C language.And then wear model which based on the theory of wear is combined to analysis the friction torque fluctuation and wear characteristics of inertial navigation bearing.In this paper,taking a certain type inertial navigation bearing as a researching subject to study the structural parameters,operating conditions and the channel surface processing quality influence on bearing friction and wear properties,and established the correctness of the inertial navigation bearing dynamics analysis model by the contrast experiment in this paper.The results are as following: 1.Too big and too small axial pre-load will increase the volatility of bearing friction torque,and bearing wear life decreases with increasing bearing pre-load,therefore,for this type inertial navigation bearing,it is suggested that the bearing axial pre-load control at about 7N ~ 8N to reduce the amplitude of friction torque and volatility,at the same time ensure the accuracy of bearing life;2.Too big pocket hole clearance and too small guide gap not only increase the value of bearing total friction torque but also increase the amplitude and volatility of the friction torque between cage and ball,while reduce the wear life of bearing.So in the design of this type inertial navigation bearing,if the condition is set,we can adjust the cage clearance ratio to reduce the total bearing friction torque and volatility,and ensure the accuracy of bearing life at the same time.3.When the peak value of the raceway waviness between 91 10-× m and 81 10-× m,bearing wear life remain unchanged with the increase of waviness peak.When the waviness peak more than 81 10-× m,bearing wear life increase with the increase of waviness peak,and then presents the tendency of first increase then decrease again.When the waviness peak is 71 10-× m,the wear life of the bearing is the largest;When the waviness peak is 73 10-× m,the wear life of the bearing is minimal;In order to ensure the wear life of the inertial navigation bearing,it is recommended that the peak value of the raceway waviness should be controlled within 71 10-× m during the machining of the bearing.4.The wear life of the inertial navigation bearing decreases with the increase of the surface roughness of the bearing raceway.So it is recommended that the roughness of the raceway surface be properly reduced during the processing to ensure the wear life of the bearing.