3D INDOOR CORRIDOR MAPPING WITH CALIBRATED ROPS OF A MULTI-FISHEYE CAMERA-RIG
Keywords: Camera Calibration, Multi-Fisheye Camera-rig, Relative Orientation Parameters, 3D reconstruction
Abstract. We present a 3D indoor mapping simulation in the location with limitations to access (i.e., pipeline drainage, sewer, box girder, etc.) by utilising a multi-fisheye camera rig. This camera rig (i.e., Pilot One) offers a 360 Field of View (FoV) coverage that represents an efficient data acquisition solution. Particular attention is focused on camera calibration consists of Interior Orientation Parameters (IOPs) and Relative Orientation Parameters (ROPs) to generate an accurate 3D reconstruction result. An appropriate Self-Calibration Bundle Adjustment (SCBA) approach, assisted with Australis coded targets, is conducted to have stable pre-calibration parameters that can be applied in a 68 meters corridor study field. We performed forward and backward data acquisition with unstitched original images and stitched images separately in a straight line to simulate data acquisition for future applications. However, due to the camera model and uncalibrated images, there is a “banana effect” in the stitched image. Twenty scale bars are used in this study. To achieve the ideal position and orientation of the scale bars, we attempt to construct a number of scenarios. The objective of this simulation is to determine the minimum number of scale bars that can be applied to a corridor where is difficult to access. We try to set up without any Control Scale Bars (CSB) with 20 Check Scale Bars (CkSBs). Even though this trial only has a 3.8 cm CkSBs error, it produced a length estimation error of 2.3 m (i.e., 3.37% of 68.1m) when compared with Terrestrial Laser Scanning.