摘要：
In grinding and polishing of the aspherical and freeform surface, the CCOS technology is widely used. It commonly uses constant pressure during polishing, and thus the desired amount of material to be remove depends on the dwell time. This paper focuses on the variable pressure CCOS polishing technology. It adds one more degree of freedom to the polishing process, in which the desired amount of material to be removed is controlled by both the polishing pressure and the dwell time. Firstly, a mathematical model was established for the variable pressure po-lishing process. Then, the stability and response speed of the output force of the polishing tool, and the stability of removal function was measured and analyzed. Finally, a material removal experiment that applied sinusoidal force was carried out on a K9 material mirror. Results show that frequency of the measured force is the same as that of the ideal sinusoidal polishing force, with a standard deviation of the force error being about 0.35 N. Its effect on PV and RMS of the finish surface is less than 9%. The spatial period of the measured surface profile is the same as that of surface profile obtained by simulation of the sinusoidal polishing process. The surface profile error is within 17%. In this paper, variable pressure polishing was achieved, and its effectiveness for optical processing was verified.%在非球面及自由曲面加工中,应用最为成熟的是计算机控制光学表面成型(CCOS)技术.现有 CCOS 技术普遍采用恒压力研抛方法,加工过程中研抛压力保持恒压,通过控制驻留时间实现所需的去除量.本文研究了基于变压力的CCOS研抛方法,增加了调控维度,通过同时控制研抛压力和驻留时间实现所需的去除量.首先,对该方法建立了加工控制的数学模型.然后,测量分析了磨头榆出力的稳定性和响应速度,去除函数的稳定性.最终,在 K9村料平面镜上开展了正弦压力抛光的村料去除实验.结果表明,实测与理想正弦研抛压力周期一致,力误差标准差约为0.35 N,对去除面形PV和RMS的影响均不到9%;实际与仿真加工的面形轮廓周期一致,加工区域的面形误差在17%以内.本文实现了变压力研抛,验证了基于变压力的CCOS研抛方法在光学加工中的有效性.
