Computer Controlled Optical Surfacing With Orbital Tool Motion

Modelling and measurement of polishing tool influence functions for edge control

“…This model, however, presents an important problem whenever the tool center is near the edge of the part, the minimum pressure can become negative, which means that this model is no longer valid. R. A. Jones suggested a linear pressure distribution model in 1986 [7]. Luna-Aguilar, et al (2004) developed this approach further using a non-linear high pressure distribution near the edge of the part; however, they did not report the models validity by experimental results [8].…”

Tool removal function modeling and processing parameters optimization for bonnet polishing

“…Since computer controlled polishing (CCP) processes were developed in the 1960s [1][2][3][4][5][6][7] , there have been a number of emerging technologies that are enabling the cost-effective manufacture of precision surfaces, particularly subaperture polishing. Subaperture polishing technologies have radically changed the landscape of precision optics manufacturing and enabled the production of components with higher accuracies and increasingly difficult figure requirements, including ion beam figuring [8] , plasma-assisted chemical etching [9] , magnetorheological finishing [10] , magnetorheological jet polishing [11,12] , even a fiber-based tool polishing [13] .…”

Parametric modeling of edge effects for polishing tool influence functions

“…Many Computer Controlled Optical Surfacing (CCOS) techniques have been presented and developed since 1972 [3][4][5][6][7][8][9][10]. The CCOS with its superb ability to control material removal is known as an ideal method to fabricate state-of-the-art optical surfaces, such as meter-class optics, segmented mirrors, off-axis mirrors, and so forth [7][8][9]11].…”

“…The dwell time map of a tool on the workpiece is usually the primary control parameter to achieve a target removal (i.e. form error on the workpiece) as it can be modulated via altering the transverse speed of the tool on the workpiece [3][4][5][6][7][8][9][10]12]. In order to calculate an optimized dwell time map, the CCOS mainly relies on a de-convolution process of the target removal using a Tool Influence Function (TIF) (i.e.…”

“…Assuming the linearity of Preston's equation the edge effects can be associated with the pressure distribution on the tool-workpiece contact area. R. A. Jones suggested a linear pressure distribution model in 1986 [8]. Luna-Aguilar, et al(2003) and Cordero-Davila, et al(2004) developed this approach further using a non-linear high pressure distribution near the edge-side of the workpiece, however they did not report the model's validity by demonstrating it using experimental evidence [13,14].…”