title: Fast Measurement and Reconstruction of Large Workpieces with Freeform Surfaces by Combining Local Scanning and Global Position Data.
abstract: In this paper, we propose a new approach for the measurement and reconstruction of large workpieces with freeform surfaces. The system consists of a handheld laser scanning sensor and a position sensor. The laser scanning sensor is used to acquire the surface and geometry information, and the position sensor is utilized to unify the scanning sensors into a global coordinate system. The measurement process includes data collection, multi-sensor data fusion and surface reconstruction. With the multi-sensor data fusion, errors accumulated during the image alignment and registration process are minimized, and the measuring precision is significantly improved. After the dense accurate acquisition of the three-dimensional (3-D) coordinates, the surface is reconstructed using a commercial software piece, based on the Non-Uniform Rational B-Splines (NURBS) surface. The system has been evaluated, both qualitatively and quantitatively, using reference measurements provided by a commercial laser scanning sensor. The method has been applied for the reconstruction of a large gear rim and the accuracy is up to 0.0963 mm. The results prove that this new combined method is promising for measuring and reconstructing the large-scale objects with complex surface geometry. Compared with reported methods of large-scale shape measurement, it owns high freedom in motion, high precision and high measurement speed in a wide measurement range.
authors.affiliation: State Key Lab of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China. cz19902013@sina.com.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Lab of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China. zhangfumin@tju.edu.cn.
authors.forename: Fumin
authors.initials: F
authors.lastname: Zhang
authors.affiliation: State Key Lab of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China. quxinghua@tju.edu.cn.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Qu
authors.affiliation: State Key Lab of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China. liangbaoqiu1@163.com.
authors.forename: Baoqiu
authors.initials: B
authors.lastname: Liang
keywords: 3-D reconstruction; combined measurement; large-scale workpieces with freeform surfaces; multi-sensor data fusion