A centroid measurement method based on 3D scanning

Abstract

The centroid coordinate serves as a critical control parameter in motion systems, including aircraft, missiles, rockets, and drones, directly influencing their motion dynamics and control performance. Traditional methods for centroid measurement often necessitate custom equipment and specialized positioning devices, leading to high costs and limited accuracy. Here, we present a centroid measurement method that integrates 3D scanning technology, enabling accurate measurement of centroid across various types of objects without the need for specialized positioning fixtures. A theoretical framework for centroid measurement was established, which combined the principle of the multi-point weighing method with 3D scanning technology. The measurement accuracy was evaluated using a designed standard component. Experimental results demonstrate that the discrepancies between the theoretical and the measured centroid of a standard component with various materials and complex shapes in the X, Y, and Z directions are 0.003 mm, 0.009 mm, and 0.105 mm, respectively, yielding a spatial deviation of 0.106 mm. Qualitative verification was conducted through experimental validation of three distinct types. They confirmed the reliability of the proposed method, which allowed for accurate centroid measurements of various products without requiring positioning fixtures. This advancement significantly broadened the applicability and scope of centroid measurement devices, offering new theoretical insights and methodologies for the measurement of complex parts and systems.

Keywords

centroid measurement / mass characteristic parameter / 3D scanning / 3D point cloud data / no specialized positioning fixtures / multi-point weighing method

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