Abstract
The capacitive displacement sensing method based on time grating employs a set of movable induction electrodes suspended with some gap width above a set of fixed excitation electrodes, and signals are obtained through electric field coupling. In this paper, we consider three features of time-grating capacitive displacement sensors that reduce the required manufacturing precision while maintaining high-accuracy measurements. First, the effect of edge roughness of the induction electrodes is suppressed by the filtering effect of the overlapping area integral method. Second, the effect of edge roughness of the excitation electrodes can be suppressed by the smoothing effect of the electric field. Third, the averaging effect of multiple induction electrodes is adopted to reduce the effect of geometric errors in the excitation electrodes. Printed circuit board manufacturing technology with a manufacturing accuracy on the order of 10 μ m is selected to fabricate a prototype time-grating capacitive sensor, and a linearity of 0.005% is obtained for a single-period range of 0.8 mm. The measurement accuracy is largely independent of the manufacturing precision owing to the three aforementioned smoothing effects, which is promising for transforming the presently challenging technology of long-range displacement measurements with nanometer-scale accuracy into a conventional technology.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.