# Real-Time 3D Profiling with RGB-D Mapping in Pipelines Using Stereo Camera Vision and Structured IR Laser Ring

## TL;DR

This paper presents a real-time 3D pipeline profiling system using stereo vision and IR laser projection, enabling accurate defect detection without calibration, suitable for robotic inspection inside pipes.

## Contribution

The novel system combines stereo vision with structured IR laser projection for real-time, calibration-free 3D mapping of pipelines, including defect detection capabilities.

## Key findings

- Detects pipe ovality changes with millimeter accuracy
- Produces real-time RGB-D maps with defect identification
- Unaffected by lateral robot movement

## Abstract

This paper is focused on delivering a solution that can scan and reconstruct the 3D profile of a pipeline in real-time using a crawler robot. A structured infrared (IR) laser ring projector and a stereo camera system are used to generate the 3D profile of the pipe as the robot moves inside the pipe. The proposed stereo system does not require field calibrations and it is not affected by the lateral movement of the robot, hence capable of producing an accurate 3D map. The wavelength of the IR light source is chosen to be non overlapping with the visible spectrum of the color camera. Hence RGB color values of the depth can be obtained by projecting the 3D map into the color image frame. The proposed system is implemented in Robotic Operating System (ROS) producing real-time RGB-D maps with defects. The defect map exploit differences in ovality enabling real-time identification of structural defects such as surface corrosion in pipe infrastructure. The lab experiments showed the proposed laser profiling system can detect ovality changes of the pipe with millimeter level of accuracy and resolution.