Study On The Measurement Method Of Parasitic Time Grating Sensor-head Coupling State

Time grating is a new type of displacement sensor developed in recent years and skillfully measure space displacement by using time through the establishment of a dual coordinate system.Among them,the parasitic time grating angle displacement sensor is a new one developed by time-grating team for it is difficult to install displacement sensor at the end of transmission chain.And the rotation angle of the end piece(This paper takes the gear as the object of study)is measured by side installation method of the parasitic grating angle displacement sensor.Due to the advantages of high precision,low cost,small size,light weight and strong anti-interference,parasitic time grating angle displacement sensor has great potential in the application of extreme and special environments.The sensor-head of parasitic time grating angle displacement sensor is installed with side installation method,which is in the convenience of the same time and also brings the installation problem.The principle of parasitic grating angle displacement sensor is based on the use of cogging aliquot,the magnetic flux modulation is realized to complete the conversion of the angle displacement to the electric traveling wave when the gear is rotated,and the angle displacement value is further solved by the subsequent signal processing system.Therefore,the regularity of the magnetic conduction modulation will be changed in varying degrees when the installation state of the sensor-head is changed,and the performance of the sensor will also be affected that causes the angle displacement measurement error.In this article,the author makes a study on the measurement method of the parasitic time grating sensor-head coupling state from three aspects including theoretical derivation,simulation analysis and experimental verification,and obtains the following achievements:(1)Further study of the principle and structure of parasitic time gratings,and analysis of the influence of the installation state of the parasitic time grating sensor-head coupling state on the sensor performance.(2)Theoretically,analysis of the coupling process of the parasitic time grating sensor-head coupling state changes to the sensing signal of the sensor unit,and the theoretical expression is deduced.(3)Numerical simulation is carried out to observe the changing regularity of sensing signal of every senor unit by using MATLAB when the sensor-head coupling state is changed,and to find out the separation method to measure each component of coupling state.(4)The finite element electromagnetic simulation software is used to verify the theoretical analysis;The selection of the reference point is determined;And the designed measurement method of sensor-head coupling state is verified and optimized.(5)The author set up the experimental platform for experimental study including the influence of sensor-head coupling state on the sensor performance,selection of reference point,and the measurement method of sensor-head coupling state,additionally the experimental results are analyzed and discussed.The study result indicates that it is possible to realize the separation measurement of the multi-degree of freedom coupling state of the parasitic time-grating sensor-head by means of embedding the independent induction coils in each sensor unit of sensor-head.