The inductosyn is a kind of high-precision angle-position sensor. It has important applications in servo table, precision
machine tool and other products. The precision of inductosyn is calibrated by its error. It's an important problem about
the error measurement in the process of production and application of the inductosyn. At present, it mainly depends on
the method of artificial measurement to obtain the error of inductosyn. Therefore, the disadvantages can't be ignored
such as the high labour intensity of the operator, the occurrent error which is easy occurred and the poor repeatability,
and so on. In order to solve these problems, a new automatic measurement method is put forward in this paper which
based on a high precision optical dividing head. Error signal can be obtained by processing the output signal of
inductosyn and optical dividing head precisely. When inductosyn rotating continuously, its zero position error can be
measured dynamically, and zero error curves can be output automatically. The measuring and calculating errors caused
by man-made factor can be overcome by this method, and it makes measuring process more quickly, exactly and reliably.
Experiment proves that the accuracy of error measuring system is 1.1 arc-second (peak - peak value).