Research On Technologies Of Precise Angle Measurement Based On Inductosyn Transducer

In order to improve the accuracy of angle measurement system with the InductosynTransducer, the error components and the calibration technology of the InductosynTransducer are researched in this paper. An Inductosyn Transducer error automatic testsystem is designed and implemented. Based on the automatic test system, theexperiments of calibration of the Inductosyn Transducer is completed. Meanwhile, thecross-calibration method used in Inductosyn Transducer is researched.First of all, based on the research on the principle and the error components of theInductosyn Transducer, the error model of the Inductosyn Transducer is improved. Anerror model with the sideband harmonic is proposed to deal with the problem that thehigh order harmonics of the Inductosyn Transducer error vary with different poles.Secondly, different types of error model of Inductosyn Transducer, the look-uptable method and formula fitting method, are analyzed and compared throughtheoretical derivation and simulation. The methods of the error model parameteridentification, including the least squares method and the harmonic decompositionmethod, are compared in field of application and feature. A method to reduce thenumber sampling points in harmonic decomposition method is proposed utilizing thealiasing effect.Furthermore, an Inductosyn Transducer error automatic test system is designed andimplemented based on a single-axis precision air bearing turntable. Based on the system,the experiment of the Inductosyn Transducer error calibration is completed. Aftercalibration, the accuracy of an angle measurement system with a small InductosynTransducer of which diameter is175mm is improved from±13arcsec to±1arcsec.Meanwhile, the separation of the unconditional part from the conditional part of theInductosyn Transducer error is researched based on the system.Finally, the effectiveness of cross calibration used in Inductosyn Transducer isverified through derivation and simulation. Meanwhile, the limitation of the method isproposed because of the too much demand of the assembly accuracy.