The Analysis and Fabrications of a Contact Type Measuring Probe for Micro/Nano CMM with an Observing Unit
Date Issued
2008
Date
2008
Author(s)
Lin, Chia-Yo
Abstract
In the modern metrological technology, coordinate measuring machings (CMM) can’t satisfy certain precision and accuracy in micro/nano scale due to the performance of the probing systems. The probing system is the limiting factor in the downscaled CMM. Many research institutes develop the probe system with expensive instrucments as sensors and complex manufacturing processes. To reduce the cost and fulfill these requirements, this study considers three main issues related to the development of the touch probe system: the fabrication of an appropriate touch probe with micro scale dimension and small mass; the cantilever beams structure with isotropic stiffness in the horizontal plane; and, DVD pick up heads as a high sensitivity sensors in distance and angle measuring. Using the clean feature of an economical fiber fusion splice system, a silica fiber probe fused spherical tip with a diameter of about 270-450 µm is made. The average of the roundness of the tip balls is 0.84 µm and the average of the offset between the axle of the fiber and the center of the tip ball is 1.03 µm. The procedure is simplified and it takes less time to make a fiber tip ball with a modified fixture. 2-level factorial experiment design is applied to identify the significant factors and the optimal conditions for fabrication of a tip ball with a desired diameter. 2 tpyes of cantilever beam structures, 3-beams and 4-beams, is introduced. Connecting with the sensing plate, cantilever beam is bent when a force, caused by the interaction between the tip ball and workpiece and transmitted with the stem, is applied on the tip ball. The displacement is calculated and simulated with the bending formulas and the finite element module of CATIA respectively. Those show that the 2 tpyes are both isotropic stiffness in the XY plane. The process of the signal of DVD pick up heads, which are utilized as high sensitivity and high resolution sensors to measuring the displacement and angle of the sensing plate, is also discussed base on the model. With these components a touch trigger probe system is developed. Index Terms —CMM probe system, DVD pick up head, distance measuring, angle measuring, fiber tip ball
Subjects
CMM contact type probe
DVD pick up head
distance measuring
angle measuring
fiber tip ball
factorial experiment design
contact force measuring
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-97-R95522716-1.pdf
Size
23.53 KB
Format
Adobe PDF
Checksum
(MD5):a7882434cd1c4f5e2e0c489622e59c08