UC Irvine researchers are leading an effort to develop
robots to internally repair the nation’s aging water mains. The robots will
pass through existing pipes and apply (from the inside) a carbon-fiber coating.
This will allow old pipes to last longer and negates the need to dig up streets
to replace pipes.
Illustration of a prototype robot designed to
repair damaged water mains.
Source: UC Irvine
Joining UC Irvine on this project are Fibrwrap Construction,
a pioneer in the trenchless application of advanced composites, and Fyfe
Company, which develops fiber-reinforced polymers for civil infrastructure
rehabilitation.
The work is being funded by the National Institute of
Standards & Technology as part of its Technology Innovation Program. This
program supports high-risk, high-reward research addressing critical national
needs, such as infrastructure monitoring and repair. Through this program, the
UC Irvine team was recently awarded $8.5 million over five years.
Driving the need for the new robots: U.S.
water mains are aging, and many of them need repairs or replacement.
In its 2009
Report Card for America’s Infrastructure, the American Society of Civil
Engineers noted that old, leaky pipes and mains lose an estimated 7 billion
gallons of clean, treated drinking water each
day.
The main obstacles to replacing and repairing water mains
are the cost and complexity.
Just how costly is it to upgrade and repair the
infrastructure? In 2009, a nearly $23 million project was begun to repair water
mains in Newark, N.J.
The goal of the project was to clean and reline about 16 miles of highly
corroded, cast-iron water mains to improve the quality of drinking water for
the city.
In addition to the cost, current methods of repairing and
replacing water mains are highly disruptive. A typical water main repair or
replacement project requires that a temporary water feed system be set up
throughout the affected areas.
Such temporary systems frequently make use of plastic pipes
and hoses that connect each home to an alternative water line. The hoses
running from the street must be connected to each house’s meter connection.
Once the project is completed, the temporary solution must be removed and the
homes must be reconnected to the new water main. In both stages, the company
working on the project needs access to every home.
Enter the Smarter Robot
Simple robots have been used to inspect pipes for some time.
The new work being carried out by UC Irvine researchers seeks to robotically
apply a carbon-fiber coating to the insides of old pipes. The challenge is that
water mains have unpredictable flaws, imperfect shapes and uneven surfaces.
This represents a far bigger technical challenge than simply cruising down a
pipe to conduct an inspection.
“The robot needs to be intelligent; it has to see and feel
and constantly adjust to the pipe surface,” says Maria Feng, civil and environmental
engineering professor at UC Irvine. “Smart robots like this are very different
from those used in manufacturing.”
To find areas needing reinforcement, researchers are
integrating an advanced sensor system into the robot to gauge contact pressure
against the pipe wall and trigger the application process.
The UC Irvine team anticipates that the robot ultimately
will adapt to various pipe sizes and conditions, and be able to lay
carbon-fiber coating 11 times faster than human crews.
