Algorithm And Strategy Of Intermediate Frequency Error Control Based On Magnetorheological Polishing

Magnetic rheological finishing technology(MRF) is known as the revolutionary technology of optical manufacturing, as it can quickly achieve ultra high precision surface shape (tens of nanometers), ultra smooth surface quality (a nanometer) and near surface defect, and it also can make optical enterprise’s manufacturing level and production efficiency improved. But in the fast removal of the low frequency surface error of the machined surface, it will often cause more small scale phase errors, resulting in mid-spatial and high frequency error control difficulties. The intermediate frequency error can affect the optical performance of the components, so it should be controlled effectively.Foreign Studies on MRF have been relatively mature, but the processing technology as the technology secret is not open, and there are some problems in the process:(1) Study on the method of if error evaluation. In order to study the evaluation method of the common optical components in the domestic and international, the power spectrum density analysis method is discussed.(2) Surface analysis software for the preparation of optical components. From the software engineering point of view, the overall structure of the surface shape analysis software is designed, and the algorithm design and function of each module is developed.(3) The influence of the shape of the polished surface on the shape of the surface is explored. The influence of the surface spectrum on the machining surface is studied by simulation.(4) The dwell time algorithm is optimized. The dwell time matrix is fluctuating along the feed direction of the polishing head, which is reflected in the discontinuity of the velocity in the polishing process. It is proposed that the residence time can be more smoothly along the direction of the polishing wheel by the filtering algorithm, that is, the speed of the adjacent two points is more close to that of the polishing wheel, which only needs a very small acceleration and a very small time to complete the whole acceleration process, thereby reducing the error caused by the fluctuation of the speed.(5) The polishing path is optimized. The advantages and disadvantages of conventional trajectory and pseudo random trajectory are studied. On the basis of the track of the grating line, a self adaptive grating line trajectory based on clustering idea is proposed, which can achieve high efficiency.In this paper, a detailed study of some key problems in the process of magnetic rheological polishing is studied, and a method for controlling the intermediate frequency error is determined.