Research On Pose Measurement System Of Shield Using The Combination Of Inclinometer And Gyroscope

A hybrid measuring system of shield tunnel construction combined with inclinometerand gyroscope is designed for the working environment influenced by vibration. Theinclinometer is used to measure the pitching angle and rolling angle directly in thecommon environment,but when a strong vibration exists, the output of the inclinometer isunstable and even unbelievable. As the gyroscope is not so senstive to the vibrations, it issurposed to use the gyroscope to compensate the angle. The main work and research are asfollows:The basic principle of measuring angle using the Fiber Optic Gyroscope is analysedand the output characteristics of the sensors in vibration environment are researched. Thefailure frequency and failure characteristics is found by experiments. The experimentsshow that the gyroscope works well in the vibration environment while there is a big errorin the output of inclinometer. The experiment also proves that there is a complementaritybetween the gyroscope and the inclinometer.In order to study the random error characteristics of the gyroscope,the Allanvariance analysis is done to build the random error modle of the gyroscope. Then using themultivariate autoregressive model to bulid the temperature drift modeling andcompasitating for the temperature drift.The multisensor fusion method based on the gyroscope zero drift estimating of thegyroscope is proposed. Using the output of the inclinometer in stable environment toestimate the zero drift of the gyroscope. This method is verified by simulation and the realexperiment shows that the zero drift of the gyroscope can be estimated by the inclinometerwith high accuracy. The experimental data shows that in static situation the angle errorintegrated from the gyroscope output with zero drift compensated in vibrationenvironment is no more than1mrad within1hour, and the the angle error is less than1mrad within half an hour in dynamic situation.