History of Laser Profiling:

The use of laser profiling for inspection of storm water drainage pipes in the U.S. transportation industry began in Florida.  In 2005, the American Association of State Highway and Transportation Officials (AASHTO) presented information on the use of laser profiling to augment current video inspection standards.  FDOT chose to require laser profiling inspection for all 100-year design life pipe specified in lettings after July 1, 2006.  PennDOT chose to follow the FDOT 100-year protocol for all lettings after August 1, 2010 per PennDOT Bulletin 601.3 (o).  These specifications apply to all 100-year design life pipe including metal, concrete and thermoplastic.

How does it work?

Laser profiling is a non-contact inspection method used to determine a pipe wall profile for pipe between 8 and 48 inches in diameter.  The pipe must be installed for a minimum of thirty (30) days prior to inspection.  The pipe must be completely clean and dry for the technology to work.  Low levels of light and humidity are also necessary to get accurate readings.  A remote control tractor unit mounted with a CCTV camera and attached laser profiling head is placed inside the pipe to be inspected.  Our Rausch equipment is self-calibrating and will immediately measure, record and correctly adjust to the pipe diameter.  The tractor is guided down the pipe and the CCTV is used to look for and record any potential problems such as cracks and holes.  When the tractor reaches the end of the pipe run (usually access point to access point), the unit makes the return run while projecting the laser onto the interior surface of the pipe.  This method is known as optical triangulation.  By knowing the position of the laser with respect to the camera and establishing which part of the sensor the light spot is viewed through, one can find the exact location of the interior pipe wall with respect to the laser and camera.  The radial distance data for several positions along the pipe is compiled and plotted yielding a three dimensional wireframe image of the pipe.  Using pan and tilt features, any anomalies, such as crack width, can be further measured and analyzed.  A real time report including video, three dimensional wireframe and deflection analysis are immediately available for review by contractors and state inspectors.  We use POSM Pro software which yields the only real-time reporting available.