Design and characteristics of a new aerostatic bearing stylus sensor for surface measurement

Abstract Stylus profilometry is extensively employed in practice due to its wide measurement range and praiseworthy stability. However, its lever structure will cause nonlinear errors and mitigated precision. Given this context, this paper proposes a new aerostatic bearing stylus sensor (ABSS) for surface measurement, which inherits the stability and large-scale measuring range while avoiding the structural nonlinear errors of the conventional stylus profilometry. The designed ABSS is composed of a magnetic levitation control system and an aerostatic bearing device in the vertical and horizontal directions, respectively. Furthermore, the bearing capacity and the radial dynamic characteristics are analyzed to ensure stylus’ scanning stability and rapid response. Template experiments with different scanning velocities of the stylus are performed to verify the natural frequency and obtain the critical velocity. Finally, the surface two/three-dimensional topographies reconstruction validates the repeatability and accuracy of the proposed ABSS compared to a commercial conventional stylus profilometry.