Abstract The equipment reported here takes 51 monolithic integrated circuits as control core，and uses the DDS chip to produce the 100 kHz sine wave signal. It uses the difference output to drive the input level of differential motion transformer, through testing the voltages of the transformers two sencondary coils and carries on computation processing of the two voltages, thus the displacement value is obtained. After the ingenious selection of direct current machine and motordriven electric circuit, magnetic rod’s precise closedloop control is completed very well.The control precision can reach to 0.5 mm.
