Behavior of Gaussian Profile Filters for Plateau Surface Structure, and Optimum Parameters

Abstract

The inner surface of engine cylinder liners has a plateau structure because of being required to have excellent sliding properties. To improve the tribological properties, the plateau surface consists of a smooth plateau region and a valley region which serves as an oil reservoir for improving lubrication. The roughness of the plateau surface is measured and evaluated for improving the fuel economy of engines in manufacturing job sites. For highly valid roughness evaluation of the plateau surface, the filtering method is important. Therefore, ISO 21920-1 has stipulated that the plateau surface should be processed with the Gaussian regression filter (GRF) of ISO 16610-31. In addition, in previous research, the fast M-estimation Gaussian filter (FMGF) was proposed as a filter that overcomes the shortcomings of GRF. The proposed the FMGF is expected to be a better filter than the GRF because of including the robustness and the characteristic becoming equal output of the Gaussian filter. On the other hand, since the parameters of the robust profile filter have different suitable values for the normal surface or the plateau surface, their settings require human judgement. Therefore, the robust profile filters are not practical in manufacturing job sites because the parameters of the robust profile filters need to be set to an optimum parameter manually, which takes time and effort. In this paper, we aim to improve the convenience of the robust profile filters in manufacturing job sites by establishing guidelines for the selection of optimum parameters.

Keywords

• surface roughness
• plateau surface structure
• robust profile filter
• Gaussian regression filter
• fast M-estimation Gaussian filter