Testing the Sandblasting Process in the Manufacturing of Reference Spheres for Non-Contact Metrology Applications.

Area of Science:

• Metrology and Measurement Science
• Materials Science and Engineering
• Optical Engineering

Background:

• Non-contact metrology technologies require precise calibration artefacts for accurate measurements.
• There is a growing industrial demand for cost-effective and highly accurate calibration standards.
• Current calibration artefacts can be expensive, limiting accessibility for some industries.

Purpose of the Study:

• To investigate the feasibility of utilizing low-cost precision spheres as calibration artefacts for non-contact metrology.
• To evaluate the effectiveness of a sandblasting process in modifying the optical properties of stainless steel spheres for metrology applications.
• To assess the impact of sandblasting on the accuracy and quality of data acquired by laser triangulation sensors.

Main Methods:

• Precision stainless steel spheres were subjected to a manual sandblasting process to reduce surface reflectivity.
• A Coordinate Measuring Machine (CMM) with a touch probe was used to measure the dimensional accuracy and form error of the sandblasted spheres.
• A laser triangulation sensor mounted on the CMM was used to capture point clouds before and after sandblasting, analyzing data quality and quantity.

Main Results:

• Sandblasting significantly altered the optical behavior of the spheres, reducing high brightness and improving laser sensor data capture.
• Analysis showed improvements in the quality and quantity of point clouds generated by the laser triangulation sensor after sandblasting.
• Measurements of diameter, form error, and standard deviation of point clouds indicated the effectiveness of the post-processing technique.

Conclusions:

• Low-cost precision spheres, when treated with sandblasting, can serve as effective calibration artefacts for non-contact metrology.
• The sandblasting process offers a cost-efficient method to enhance the suitability of spheres for metrological calibration.
• This approach provides a viable solution for improving the accuracy and reliability of non-contact measurement systems.