Research On Model Optimization And Error Self-correction Of Multiple Read-head Displacement Sensor

In order to improve the accuracy of grating displacement sensors such as gratings,capacitive grids,ball grids,time grids,and induction synchronizers,there are generally two methods:use increase the grid line density and the number of readheads,or use high-precision meter detection and correction errors.The former requires high processing and installation of the sensors,and the latter has poor sensor accuracy for a long time.This paper in view of the above problems presents a new method for constructing quadrature signals based on equal-difference phase to achieve multi-head reading measurement,error feature parameters identification and error selfcorrection.The methord dose not change the processing and installation complexity,the number of slots of the stator and the rotor are close to each other,and the intensity of the induction signal is high;The multi-head readheads constructed by signal processing methord are distributed on the same stator,and the consistency of the reading head is good.Based on the above analysis,this paper mainly carried out the following work:(1)Come up with a method of constructing quadrature base on equal-difference phases.established a mathematical model of orthogonal signal.Deep studied the physical model of the sensor.studied the error characteristics base on variable area manner.(2)Studied the sensor of the simulation model and calculated the different types sensors of displacement error characteristic based on phase-locked tracking algorithm.optimized multi-reader model of the sensor.Study the influence of the sensor on the sensor air gap size,and optimized the structure of the sensor.(3)Studied the error law of multi head reading displacement sensors and divided into two different types of error.proposed a method for correcting two types of errors:different error are modified with the displacement solver,and the same error is modified with the error feature parameter identification algorithm.(4)Studied the amplitude error?phase shift error methods of the detection and correction.established a displacement solver algorithm model.realized the correction of the influence of different errors on the multi head reading displacement sensor.(5)Studied a method of automatically recognizing sensor error feature parameters by multi head reading and multi position.established an error parameter identification algorithm model,realized the correction of the influence of same errors on the multi head reading displacement sensor.(6)Set up a multi head reading displacement sensor experimental platform,by high-accuracy raster measurement is true,Comparing the accuracy of the sensor before and after correction: the accuracy of the multi head reading sensor is clearly higher than before the sensor of uncorrected.To sum up:the paper established a mathematical model by orthogonal signals,constructed a physical model of a multi-head reading sensors,studied the structure principle and displacement calculation principle of the multi head reading displacement sensor.This paper established different types of sensor for the moder,optimized the model structure of the sensor;Detailed analysis of the sensor error,divided into two different types of error,using different models to eliminate the error of the sensor;Finally,it verified the correctness of the error correction scheme through experiments,and it has a good practicality.