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This paper describes the development of a system and associated software capable of capturing 3D LIDAR data from surfaces
up to 20m from the sensor. The chief concern of this initial system is to minimize cost which, for this initial system, is
approximately $10.5k (USD). Secondary considerations for the system include portability, robustness, and size. The system
hardware consists of two motors and a single-point sensor, capable of measuring the range of a single surface point location.
The motors redirect the emitted laser along lines nearly equivalent to that specified by a spherical coordinate system generating
a spherical range image, r = f ( φ, θ). This article describes the technical aspects of the scanner design which include
a bill-of-materials for the scanner components and the mathematical model for the measured 3D point data. The designed
system was built in 2007 and has since been used in the field twice: (1) for scanning ruins and underground cisterns within
Mayan cities near Merida, Mexico and (2) for scanning the ruins of a Crusader castle at Apollonia-Arsuf, located on the
Mediterranean shore near Herzliya, Israel. Using this system in these vastly different environments has provided a number
of useful insights or "best practices" on the use of inexpensive LIDAR sensors which are discussed in this paper. We also
discuss a measurement model for the generated data and an efficient and easy-to-implement algorithm for polygonizing the
measured 3D (x,y, z) data. Specific applications of the developed system to archaeological and anthropological problems are
discussed.
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