Ground Based LiDAR Georeferencing using Dual GPS Antenna Attitude

Ben Wilkinson and Ahmed Mohamed

Abstract:	Georeferencing of terrestrial LiDAR scanning data is currently performed by using control points in the scanning field. This procedure is often troublesome because control stations are not always available within the scanning range; and field procedures can be laborious and involve extra equipment and target setups. The conventional method also allows for possible human error due to target information bookkeeping. Additionally, the accuracy of this procedure varies according to the quality of the control used. We describe an innovative method for determining the absolute orientation of LiDAR point clouds using GPS measurements from two antennas firmly mounted on the optical head of the LiDAR scanner. By adding a dual GPS antenna apparatus to the scanner setup, thereby supplanting the use of multiple ground control points scattered throughout the project, we mitigate not only the problems associated with georeferencing but also induce a more efficient set up procedure while maintaining a usable level of precision. We also describe a new method of linearizing the nonlinear georeferencing model using its skew-symmetry properties. Simulation and real world experimentation of our prototype implementation suggest a precision of about 0.05 degrees (~ 1 milliradian) for the three Euler attitude angles. We show that our method can achieve a practical precision for the orientation of terrestrial LiDAR scan data for several applications. This work paves the way for augmentations of the presented dual antenna method with other techniques including Kalman filtering. This can be done through the addition of measurements from the scanner’s horizontal rotation controller and a more rigorous nonlinear solution of the angles by using the current solutions as initial approximations. Our method can help alleviate the problems associated with the conventional technique and can allow for an increased number of practical applications for geo-referenced terrestrial LiDAR.
Published in:	Proceedings of the 2009 International Technical Meeting of The Institute of Navigation January 26 - 28, 2009 Disney's Paradise Pier Hotel Anaheim, CA
Pages:	375 - 383
Cite this article:	Wilkinson, Ben, Mohamed, Ahmed, "Ground Based LiDAR Georeferencing using Dual GPS Antenna Attitude," Proceedings of the 2009 International Technical Meeting of The Institute of Navigation, Anaheim, CA, January 2009, pp. 375-383.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In