1091

For the ultra-precision single point diamond turning, the spidle system is a core component and plays a decisive role in precise machining. The unbalancing state in spinle can degrade the quality of machining surface. Therefore, the spindle system must be exceptionally well balanced before processing. A precise the spindle unbalancing measurement method, adopting the real-time data in CNC System of SPDT and combining with disturbance observer (DOB), is proposed. According to the experiment result, the accuracy of this method is up to G0.00648. Since this method does not require addition sensors to install, it is easily popularized and applied in the field of ultra-precision machine tools.